[Title 40 CFR ]
[Code of Federal Regulations (annual edition) - July 1, 2002 Edition]
[From the U.S. Government Printing Office]



[[Page 1]]



                    40


          Parts 136 to 149

                         Revised as of July 1, 2002

Protection of Environment





          Containing a codification of documents of general 
          applicability and future effect
          As of July 1, 2002
          With Ancillaries
          Published by
          Office of the Federal Register
          National Archives and Records
          Administration

A Special Edition of the Federal Register



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                            Table of Contents



                                                                    Page
  Explanation.................................................       v

  Title 40:
          Chapter I--Environmental Protection Agency 
          (Continued)                                                3
  Finding Aids:
      Material Approved for Incorporation by Reference........     841
      Table of CFR Titles and Chapters........................     859
      Alphabetical List of Agencies Appearing in the CFR......     877
      List of CFR Sections Affected...........................     887



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                     ----------------------------

                     Cite this Code:  CFR
                     To cite the regulations in 
                       this volume use title, 
                       part and section number. 
                       Thus, 40 CFR 136.1 refers 
                       to title 40, part 136, 
                       section 1.

                     ----------------------------

[[Page v]]



                               EXPLANATION

    The Code of Federal Regulations is a codification of the general and 
permanent rules published in the Federal Register by the Executive 
departments and agencies of the Federal Government. The Code is divided 
into 50 titles which represent broad areas subject to Federal 
regulation. Each title is divided into chapters which usually bear the 
name of the issuing agency. Each chapter is further subdivided into 
parts covering specific regulatory areas.
    Each volume of the Code is revised at least once each calendar year 
and issued on a quarterly basis approximately as follows:

Title 1 through Title 16.................................as of January 1
Title 17 through Title 27..................................as of April 1
Title 28 through Title 41...................................as of July 1
Title 42 through Title 50................................as of October 1

    The appropriate revision date is printed on the cover of each 
volume.

LEGAL STATUS

    The contents of the Federal Register are required to be judicially 
noticed (44 U.S.C. 1507). The Code of Federal Regulations is prima facie 
evidence of the text of the original documents (44 U.S.C. 1510).

HOW TO USE THE CODE OF FEDERAL REGULATIONS

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    To determine whether a Code volume has been amended since its 
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Register page number of the latest amendment of any given rule.

EFFECTIVE AND EXPIRATION DATES

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OMB CONTROL NUMBERS

    The Paperwork Reduction Act of 1980 (Pub. L. 96-511) requires 
Federal agencies to display an OMB control number with their information 
collection request.

[[Page vi]]

Many agencies have begun publishing numerous OMB control numbers as 
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OBSOLETE PROVISIONS

    Provisions that become obsolete before the revision date stated on 
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INCORPORATION BY REFERENCE

    What is incorporation by reference? Incorporation by reference was 
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This material, like any other properly issued regulation, has the force 
of law.
    What is a proper incorporation by reference? The Director of the 
Federal Register will approve an incorporation by reference only when 
the requirements of 1 CFR part 51 are met. Some of the elements on which 
approval is based are:
    (a) The incorporation will substantially reduce the volume of 
material published in the Federal Register.
    (b) The matter incorporated is in fact available to the extent 
necessary to afford fairness and uniformity in the administrative 
process.
    (c) The incorporating document is drafted and submitted for 
publication in accordance with 1 CFR part 51.
    Properly approved incorporations by reference in this volume are 
listed in the Finding Aids at the end of this volume.
    What if the material incorporated by reference cannot be found? If 
you have any problem locating or obtaining a copy of material listed in 
the Finding Aids of this volume as an approved incorporation by 
reference, please contact the agency that issued the regulation 
containing that incorporation. If, after contacting the agency, you find 
the material is not available, please notify the Director of the Federal 
Register, National Archives and Records Administration, Washington DC 
20408, or call (202) 523-4534.

CFR INDEXES AND TABULAR GUIDES

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separate volume, revised annually as of January 1, entitled CFR Index 
and Finding Aids. This volume contains the Parallel Table of Statutory 
Authorities and Agency Rules (Table I). A list of CFR titles, chapters, 
and parts and an alphabetical list of agencies publishing in the CFR are 
also included in this volume.
    An index to the text of ``Title 3--The President'' is carried within 
that volume.
    The Federal Register Index is issued monthly in cumulative form. 
This index is based on a consolidation of the ``Contents'' entries in 
the daily Federal Register.
    A List of CFR Sections Affected (LSA) is published monthly, keyed to 
the revision dates of the 50 CFR titles.

[[Page vii]]


REPUBLICATION OF MATERIAL

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in the Code of Federal Regulations.

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or write to the Director, Office of the Federal Register, National 
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                              Raymond A. Mosley,
                                    Director,
                          Office of the Federal Register.

July 1, 2002.



[[Page ix]]



                               THIS TITLE

    Title 40--Protection of Environment is composed of twenty-eight 
volumes. The parts in these volumes are arranged in the following order: 
parts 1-49, parts 50-51, part 52 (52.01-52.1018), part 52 (52.1019-End), 
parts 53-59, part 60 (60.1-End), part 60 (Appendices), parts 61-62, part 
63 (63.1-63.599), part 63 (63.600-1-63.1199), part 63 (63.1200-End), 
parts 64-71, parts 72-80, parts 81-85, part 86 (86.1-86.599-99) part 86 
(86.600-1-End), parts 87-99, parts 100-135, parts 136-149, parts 150-
189, parts 190-259, parts 260-265, parts 266-299, parts 300-399, parts 
400-424, parts 425-699, parts 700-789, and part 790 to End. The contents 
of these volumes represent all current regulations codified under this 
title of the CFR as of July 1, 2002.

    Chapter I--Environmental Protection Agency appears in all twenty-
eight volumes. An alphabetical Listing of Pesticide Chemicals Index 
appears in parts 150-189. Redesignation Tables appear in the volumes 
containing parts 50-51, parts 150-189, and parts 700-789. Regulations 
issued by the Council on Environmental Quality appear in the volume 
containing part 790 to End. The OMB control numbers for title 40 appear 
in Sec. 9.1 of this chapter.

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                   TITLE 40--PROTECTION OF ENVIRONMENT




                  (This book contains parts 136 to 149)

  --------------------------------------------------------------------
                                                                    Part

chapter i--Environmental Protection Agency (Continued)......         136

[[Page 3]]



         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)




  --------------------------------------------------------------------


  Editorial Note: Nomenclature changes to chapter I appear at 65 FR 
47324, 47325, Aug. 2, 2000; 66 FR 34375, 34376, June 28, 2001.

                SUBCHAPTER D--WATER PROGRAMS (CONTINUED)
Part                                                                Page
136             Guidelines establishing test procedures for 
                    the analysis of pollutants..............           5
140             Marine sanitation device standard...........         330
141             National primary drinking water regulations.         334
142             National primary drinking water regulations 
                    implementation..........................         559
143             National secondary drinking water 
                    regulations.............................         613
144             Underground injection control program.......         615
145             State UIC program requirements..............         682
146             Underground injection control program: 
                    Criteria and standards..................         695
147             State underground injection control programs         726
148             Hazardous waste injection restrictions......         824
149             Sole source aquifers........................         834

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                SUBCHAPTER D--WATER PROGRAMS (CONTINUED)





PART 136--GUIDELINES ESTABLISHING TEST PROCEDURES FOR THE ANALYSIS OF POLLUTANTS--Table of Contents




Sec.
136.1  Applicability.
136.2  Definitions.
136.3  Identification of test procedures.
136.4  Application for alternate test procedures.
136.5  Approval of alternate test procedures.

Appendix A to Part 136--Methods for Organic Chemical Analysis of 
          Municipal and Industrial Wastewater
Appendix B to Part 136--Definition and Procedure for the Determination 
          of the Method Detection Limit--Revision 1.11
Appendix C to Part 136--Inductively Coupled Plasma--Atomic Emission 
          Spectrometric Method for Trace Element Analysis of Water and 
          Wastes Method 200.7
Appendix D to Part 136--Precision and Recovery Statements for Methods 
          for Measuring Metals

    Authority: Secs. 301, 304(h), 307 and 501(a), Pub. L. 95-217, 91 
Stat. 1566, et seq. (33 U.S.C. 1251, et seq.) (the Federal Water 
Pollution Control Act Amendments of 1972 as amended by the Clean Water 
Act of 1977).



Sec. 136.1  Applicability.

    The procedures prescribed herein shall, except as noted in 
Sec. 136.5, be used to perform the measurements indicated whenever the 
waste constituent specified is required to be measured for:
    (a) An application submitted to the Administrator, or to a State 
having an approved NPDES program for a permit under section 402 of the 
Clean Water Act of 1977, as amended (CWA), and/or to reports required to 
be submitted under NPDES permits or other requests for quantitative or 
qualitative effluent data under parts 122 to 125 of title 40, and,
    (b) Reports required to be submitted by discharges under the NPDES 
established by parts 124 and 125 of this chapter, and,
    (c) Certifications issued by States pursuant to section 401 of the 
CWA, as amended.

[38 FR 28758, Oct. 16, 1973, as amended at 49 FR 43250, Oct. 26, 1984]



Sec. 136.2  Definitions.

    As used in this part, the term:
    (a) Act means the Clean Water Act of 1977, Pub. L. 95-217, 91 Stat. 
1566, et seq. (33 U.S.C. 1251 et seq.) (The Federal Water Pollution 
Control Act Amendments of 1972 as amended by the Clean Water Act of 
1977).
    (b) Administrator means the Administrator of the U.S. Environmental 
Protection Agency.
    (c) Regional Administrator means one of the EPA Regional 
Administrators.
    (d) Director means the Director of the State Agency authorized to 
carry out an approved National Pollutant Discharge Elimination System 
Program under section 402 of the Act.
    (e) National Pollutant Discharge Elimination System (NPDES) means 
the national system for the issuance of permits under section 402 of the 
Act and includes any State or interstate program which has been approved 
by the Administrator, in whole or in part, pursuant to section 402 of 
the Act.
    (f) Detection limit means the minimum concentration of an analyte 
(substance) that can be measured and reported with a 99% confidence that 
the analyte concentration is greater than zero as determined by the 
procedure set forth at appendix B of this part.

[38 FR 28758, Oct. 16, 1973, as amended at 49 FR 43250, Oct. 26, 1984]



Sec. 136.3  Identification of test procedures.

    (a) Parameters or pollutants, for which methods are approved, are 
listed together with test procedure descriptions and references in 
Tables IA, IB, IC, ID, IE, and IF. The full text of the referenced test 
procedures are incorporated by reference into Tables IA, IB, IC, ID, IE, 
and IF. The references and the sources which are available are given in 
paragraph (b) of this section. These test procedures are incorporated as 
they exist on the day of approval and a notice of any change in these 
test procedures will be published in the Federal Register. The discharge 
parameter values for which reports are required must be determined by 
one of

[[Page 6]]

the standard analytical test procedures incorporated by reference and 
described in Tables IA, IB, IC, ID, IE, and IF, or by any alternate test 
procedure which has been approved by the Administrator under the 
provisions of paragraph (d) of this section and Secs. 136.4 and 136.5. 
Under certain circumstances (paragraph (b) or (c) of this section or 40 
CFR 401.13) other test procedures may be used that may be more 
advantageous when such other test procedures have been previously 
approved by the Regional Administrator of the Region in which the 
discharge will occur, and providing the Director of the State in which 
such discharge will occur does not object to the use of such alternate 
test procedure.

[[Page 7]]



                                                     Table IA.--List of Approved Biological Methods
--------------------------------------------------------------------------------------------------------------------------------------------------------
        Parameter and units                 Method \1\                    EPA            Standard methods, 18th Ed.      ASTM              USGS
--------------------------------------------------------------------------------------------------------------------------------------------------------
Bacteria:
    1. Coliform (fecal), number     Most Probable Number        p. 132 \3\              9221C E \4\                  ...........  ......................
     per 100 mL.                     (MPN), 5 tube.             p. 124 \3\              9222D \4\                                 B-0050-85 \5\
                                    3 dilution, or Membrane
                                     filter (MF) \2\, single
                                     step.
    2. Coliform (fecal) in          MPN, 5 tube, 3 dilution,    p. 132 \3\              9221C E \4\                  ...........  ......................
     presence of chlorine, number    or.                        p. 124 \3\              9222D \4\
     per 100 mL.                    MF, single step \6\.......
    3. Coliform (total), number     MPN, 5 tube, 3 dilution,    p. 114 \3\              9221B \4\                    ...........  ......................
     per 100 mL.                     or.                        p. 108 \3\              9222B \4\                                 B-0025-85 \5\
                                    MF \2\ single step or two
                                     step.
    4. Coliform (total), in         MPN, 5 tube, 3 dilution,    p. 114 \3\              9221B \4\                    ...........  ......................
     presence of chlorine, number    or.                        p. 111 \3\              9222(B+B.5c) \4\
     per 100 mL.                    MF \2\ with enrichment....
    5. Fecal streptococci, number   MPN, 5 tube, 3 dilution...  p. 139 \3\              9230B \4\                    ...........  ......................
     per 100 mL.                    MF \2\, or................  p. 136 \3\              9230C \4\                                 B-0055-85 \5\
                                    Plate count...............  p. 143 \3\
Aquatic Toxicity:
    6. Toxicity, acute, fresh       Daphnia, Ceriodaphnia,      Sec. 9 \7\              ...........................  ...........  ......................
     water organisms, LC50,          Fathead Minnow, Rainbow
     percent effluent.               Trout, Brook Trout, or
                                     Bannerfish Shiner
                                     mortality.
    7. Toxicity, acute, estuarine   Mysid, Sheepshead Minnow,   Sec. 9 \7\              ...........................  ...........  ......................
     and marine organisms, LC50,     or Menidia spp. mortality.
     percent effluent.
    8. Toxicity, chronic, fresh     Fathead minnow larval       1000.0 \8\              ...........................  ...........  ......................
     water organisms, NOEC or        survival and growth.       1001.0 \8\
     IC25, percent effluent.        Fathead minnow embryo-
                                     larval survival and        1002.0 \8\
                                     teratogenicity.            1003.0 \8\
                                    Ceriodaphnia survival and
                                     reproduction.
                                    Selenastrum growth........
    9. Toxicity, chronic,           Sheepshead minnow larval    1004.0 \9\              ...........................  ...........  ......................
     estuarine and marine            survival and growth.       1005.0 \9\
     organisms, NOEC or IC25,       Sheepshead minnow embryo-
     percent effluent.               larval survival and        1006.0 \9\
                                     teratogenicity.            1007.0 \9\
                                    Menidia beryllina larval    1008.0 \9\
                                     and growth.                1009.0 \9\
                                    Mysidopsis bahia survival,
                                     growth, and fecundity.
                                    Arbacia punctulata
                                     fertilization.
                                    Champia parvula
                                     reproduction.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Notes to Table IA:
\1\ The method must be specified when results are reported.
\2\ A 0.45 um membrane filter (MF) or other pore size certified by the manufacturer to fully retain organisms to be cultivated and to be free of
  extractables which could interfere with their growth.
\3\ USEPA. 1978. Microbiological Methods for Monitoring the Environment, Water, and Wastes. Environmental Monitoring and Support Laboratory, U.S.
  Environmental Protection Agency, Cincinnati, Ohio. EPA/600/8-78/017.
\4\ APHA. 1992. Standard Methods for the Examination of Water and Wastewater. American Public Health Association. 18th Edition. Amer. Publ. Hlth.
  Assoc., Washington, DC.
\5\ USGS. 1989. U.S. Geological Survey Techniques of Water-Resources Investigations, Book 5, Laboratory Analysis, Chapter A4, Methods for Collection and
  Analysis of Aquatic Biological and Microbiological Samples, U.S. Geological Survey, U.S. Department of Interior, Reston, Virginia.
\6\ Because the MF technique usually yields low and variable recovery from chlorinated wastewaters, the Most Probable Number method will be required to
  resolve any controversies.
\7\ USEPA. 1993. Methods for Measuring the Acute Toxicity of Effluents to Freshwater and Marine Organisms. Fourth Edition. Environmental Monitoring
  Systems Laboratory, U.S. Environmental Protection Agency, Cincinnati, Ohio. August 1993, EPA/600/4-90/027F.

[[Page 8]]

 
\8\ USEPA. 1994. Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Third Edition.
  Environmental Monitoring Systems Laboratory, U.S. Environmental Protection Agency USEPA. 1994, Cincinnati, Ohio (July 1994, EPA/600/4-91/002).
\9\ Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Marine and Estuarine Organisms. Second Edition.
  Environmental Monitoring Systems Laboratory, U.S. Environmental Protection Agency, Cincinnati, Ohio (July 1994, EPA/600/4-91/003). These methods do
  not apply to marine waters of the Pacific Ocean.


                                                  Table IB.--List of Approved Inorganic Test Procedures
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                            Reference (method number or page)
  Parameter, units and method  -------------------------------------------------------------------------------------------------------------------------
                                  EPA 1,35      STD methods  18th ed.                 ASTM                       USGS \2\                  Other
--------------------------------------------------------------------------------------------------------------------------------------------------------
1. Acidity, as CaCO3, mg/L:
    Electrometric endpoint or         305.1  2310 B(4a)................  D1067-92
     phenolphthalein endpoint.
2. Alkalinity, as CaCO3, mg/L:
    Electrometric or                  310.1  2320 B....................  D1067-92.....................  I-1030-85................  973.43.\3\
     Colorimetric titration to        310.2                                                             I-2030-85................
     pH 4.5, manual or
     automated.
3. Aluminum--Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration \36\.        202.1  3111 D....................  .............................  I-3051-85
    AA furnace................        202.2  3113 B
    Inductively Coupled Plasma/   \5\ 200.7  3120 B
     Atomic Emission
     Spectrometry (ICP/AES)
     \36\.
    Direct Current Plasma       ...........  ..........................  D4190-82(88).................  .........................  Note 34.
     (DCP) \36\.
    Colorimetric (Eriochrome    ...........  3500-Al D
     cyanine R).
4. Ammonia (as N), mg/L:
    Manual, distillation (at          350.2  4500-NH3B.................  .............................  .........................  973.49.\3\
     pH 9.5),\6\ followed by.
    Nesslerization............        350.2  4500-NH3C.................  D1426-93(A)..................  I-3520-85................  973.49.\3\
    Titration.................        350.2  4500-NH3E
    Electrode.................        350.3  4500-NH3F or G............  D1426-93(B)
    Automated phenate, or.....        350.1  4500-NH3H.................  .............................  I-4523-85
    Automated electrode.......  ...........  ..........................  .............................  .........................  Note 7.
5. Antimony-Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration \36\.        204.1  3111 B
    AA furnace................        204.2  3113 B
    ICP/AES \36\..............    \5\ 200.7  3120 B
6. Arsenic-Total,\4\ mg/L:
    Digestion \4\ followed by.        206.5
        AA gaseous hydride....        206.3  3114 B 4.d................  D2972-93(B)..................  I-3062-85
        AA furnace............        206.2  3113 B....................  D2972-93(C)
        ICP/AES,\36\ or.......    \5\ 200.7  3120 B
        Colorimetric (SDDC)...        206.4  3500-As C.................  D2972-93(A)..................  I-3060-85
7. Barium--Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration \36\.        208.1  3111 D....................  .............................  I-3084-85
    AA furnace................        208.2  3113 B....................  D4382-91
    ICP/AES \36\..............    \5\ 200.7  3120 B
    DCP \36\..................  ...........  ..........................  .............................  .........................  Note 34.
8. Beryllium--Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration......        210.1  3111 D....................  D3645-93(88)(A)..............  I-3095-85
    AA furnace................        210.2  3113 B....................  D3645-93(88)(B)
    ICP/AES...................    \5\ 200.7  3120 B
    DCP, or...................  ...........  ..........................  D4190-82(88).................  .........................  Note 34.

[[Page 9]]

 
    Colorimetric (aluminon)...  ...........  3500-Be D
9. Biochemical oxygen demand
 (BOD5), mg/L:
    Dissolved Oxygen Depletion        405.1  5210 B....................  .............................  I-1578-78 \8\............  973.44,\3\ p. 17.\9\
10. Boron \37\--Total, mg/L:
    Colorimetric (curcumin)...        212.3  4500-B B..................  .............................  I-3112-85
    ICP/AES, or...............    \5\ 200.7  3120 B
    DCP.......................  ...........  ..........................  D4190-82(88).................  .........................  Note 34
11. Bromide, mg/L:
    Titrimetric...............        320.1  ..........................  D1246-82(88)(C)..............  I-1125-85................  p. S44.\10\
12. Cadmium--Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration \36\.        213.1  3111 B or C...............  D3557-90(A or B).............  I-3135-85 or I-3136-85...  974.27,\3\ p. 37.\9\
    AA furnace................        213.2  3113 B....................  D3557-90(D)
    ICP/AES \36\..............    \5\ 200.7  3120 B....................  .............................  I-1472-85
    DCP \36\..................  ...........  ..........................  D4190-82(88).................  .........................  Note 34.
    Voltametry,\11\ or........  ...........  ..........................  D3557-90(C)
    Colorimetric (Dithizone)..  ...........  3500-Cd D
13. Calcium--Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration......        215.1  3111 B....................  D511-93(B)...................  I-3152-85
    ICP/AES...................    \5\ 200.7  3120 B
    DCP, or...................  ...........  ..........................  .............................  .........................  Note 34.
    Titrimetric (EDTA)........        215.2  3500-Ca D.................  D511-93(A)
14. Carbonaceous biochemical
 oxygen demand (CBOD5), mg/L
 \12\:
    Dissolved Oxygen Depletion  ...........  5210 B
     with nitrification
     inhibitor.
15. Chemical oxygen demand            410.1  5220 C....................  D1252-88(A)..................  I-3560-85................  973.46,\3\ p. 17.\9\
 (COD), mg/L; Titrimetric, or.        410.2                                                             I-3562-85................
                                      410.3
    Spectrophotometric, manual        410.4  5220 D....................  D1252-88(B)..................  I-3561-85................  Notes 13 or 14.
     or automated.
16. Chloride, mg/L:
    Titrimetric (silver         ...........  4500-Cl- B................  D512-89(B)...................  I-1183-85
     nitrate) or.
    (Mercuric nitrate)........        325.3  4500-Cl- C................  D512-89(A)...................  I-1184-85................  973.51.\3\
    Colorimetric, manual or...  ...........  ..........................  .............................  I-1187-85
    Automated (Ferricyanide)..     325.1 or  4500-Cl-E.................  .............................  I-2187-85
                                      325.2
17. Chlorine--Total residual,
 mg/L; Titrimetric:
    Amperometric direct.......        330.1  4500-Cl D.................  D1253-86(92)
    Iodometric direct.........        330.3  4500-Cl B
    Back titration ether end-         330.2  4500-Cl C
     point \15\ or.
    DPD-FAS...................        330.4  4500-Cl F
    Spectrophotometric, DPD...        330.5  4500-Cl G
    Or Electrode..............  ...........  ..........................  .............................  .........................  Note 16.
18. Chromium VI dissolved, mg/
 L; 0.45 micron filtration
 followed by:
    AA chelation-extraction or        218.4  3111 C....................  .............................  I-1232-85
    Colorimetric                ...........  3500-Cr D.................  D1687-92(A)..................  I-1230-85
     (Diphenylcarbazide).
19. Chromium--Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration \36\.        218.1  3111 B....................  D1687-92(B)..................  I-3236-85................  974.27.\3\
    AA chelation-extraction...        218.3  3111 C
    AA furnace................        218.2  3113 B....................  D1687-92(C)

[[Page 10]]

 
    ICP/AES \36\..............    \5\ 200.7  3120 B
    DCP,\36\ or...............  ...........  ..........................  D4190-82(88).................  .........................  Note 34.
    Colorimetric                ...........  3500-Cr D
     (Diphenylcarbazide)
20. Cobalt--Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration......        219.1  3111 B or C...............  D3558-90(A or B).............  I-3239-85................  p. 37.\9\
    AA furnace................        219.2  3113 B....................  D3558-90(C)
    ICP/AES...................    \5\ 200.7  3120 B
    DCP.......................  ...........  ..........................  D4190-82(88).................  .........................  Note 34.
21. Color platinum cobalt
 units or dominant wavelength,
 hue, luminance purity:
    Colorimetric (ADMI), or...        110.1  2120 E....................  .............................  .........................  Note 18.
    (Platinum cobalt), or.....        110.2  2120 B....................  .............................  I-1250-85................  .....................
    Spectrophotometric........        110.3  2120 C
22. Copper--Total,4 mg/L;
 Digestion 4 followed by:
    AA direct aspiration 36...        220.1  3111 B or C...............  D1688-90(A or B).............  I-3270-85 or I3271-85....  974.27 3 p. 37.9
    AA furnace................        220.2  3113 B....................  D1688-90(C)
    ICP/AES 36................      5 200.7  3120 B
    DCP 36 or.................  ...........  ..........................  D4190-82(88).................  .........................  Note 34.
    Colorimetric (Neocuproine)  ...........  3500-Cu D
     or.
    (Bicinchoninate)..........  ...........  Or E......................  .............................  .........................  Note 19.
23. Cyanide--Total, mg/L:
    Manual distillation with    ...........  4500-CN C.................  D2036-91(A)
     MgCl2 followed by.
    Titrimetric, or...........  ...........  4500-CN D.................  .............................  .........................  p. 22.9
    Spectrophotometric, manual     31 335.2  4500-CN E.................  D2036-91(A)..................  I-3300-85
     or.
    Automated 20..............     31 335.3
24. Available Cyanide, mg/L
    Cyanide amenable to               335.1  4500-CN G.................  D2036-91(B)..................
     chlorination (CATC),
     Manual distillation with
     MgCl2 followed by
     titrimetry or
     spectrophotometry.
    Flow injection and ligand                                            .............................  .........................  44 OIA-1677
     exchange, followed by
     amperometry.
25. Fluoride--Total, mg/L:
    Manual distillation 6       ...........  4500-F B
     followed by.
    Electrode, manual or......        340.2  4500-F C..................  D1179-93(B)
    Automated.................  ...........  ..........................  .............................  I-4327-85
    Colorimetric (SPADNS).....        340.1  4500-F D..................  D1179-93(A)
    Or Automated complexone...        340.3  4500-F E
26. Gold--Total,4 mg/L;
 Digestion 4 followed by:
    AA direct aspiration......        231.1  3111 B
    AA furnace, or............        231.2
    DCP.......................  ...........  ..........................  .............................  .........................  Note 34.
27. Hardness--Total, as CaCO3,
 mg/L
    Automated colorimetric,...        130.1

[[Page 11]]

 
    Titrimetric (EDTA), or Ca         130.2  2340 B or C...............  D1126-86(92).................  I-1338-85................  973.52B.3
     plus Mg as their
     carbonates, by
     inductively coupled
     plasma or AA direct
     aspiration. (See
     Parameters 13 and 33).
28. Hydrogen ion (pH), pH
 units
    Electrometric measurement,        150.1  4500-H= B.................  D1293-84(90)(A or B).........  I-1586-85................  973.41.3
     or.
    Automated electrode.......  ...........  ..........................  .............................  .........................  Note 21.
29. Iridium--Total,4 mg/L;
 Digestion 4 followed by:
    AA direct aspiration or...        235.1  3111 B
    AA furnace................        235.2
30. Iron--Total,4 mg/L;
 Digestion 4 followed by:
    AA direct aspiration 36...        236.1  3111 B or C...............  D1068-90(A or B).............  I-3381-85................  974.27.3
    AA furnace................        236.2  3113 B....................  D1068-90(C)
    ICP/AES 36................      5 200.7  3120 B
    DCP 36 or.................  ...........  ..........................  D4190-82(88).................  .........................  Note 34.
    Colorimetric                ...........  3500-Fe D.................  D1068-90(D)..................  .........................  Note 22.
     (Phenanthroline).
31. Kjeldahl Nitrogen--Total,
 (as N), mg/L:
    Digestion and distillation        351.3  4500-NH3B or C............  D3590-89(A)..................  .........................  .....................
     followed by:.
    Titration.................        351.3  4500-NH3E.................  D3590-89(A)..................  .........................  973.483.
    Nesslerization............        351.3  4500-NH3C.................  D3590-89(A)..................  .........................  .....................
    Electrode.................        351.3  4500-NH3F or G............  .............................  .........................  .....................
    Automated phenate                 351.1  ..........................  .............................  I-4551-788...............  .....................
     colorimetric.
    Semi-automated block              351.2  ..........................  D3590-89(B)..................  .........................  .....................
     digester colorimetric.
    Manual or block digester          351.4  ..........................  D3590-89(A)..................  .........................  .....................
     potentiometric.
    Block Digester, followed
     by:.
    Auto distillation and       ...........  ..........................  .............................  .........................  Note 39.
     Titration, or.
    Nesslerization............  ...........  ..........................  .............................  .........................  Note 40.
    Flow injection gas          ...........  ..........................  .............................  .........................  Note 41.
     diffusion.
 
32. Lead--Total,4 mg/L;
 Digestion \4\ followed by:
    AA direct aspiration 36...        239.1  3111 B or C...............  D3559-90(A or B).............  I-3399-85................  974.27.3
    AA furnace................        239.2  3113 B....................  D3559-90(D)
    ICP/AES 36................      5 200.7  3120 B
    DCP 36....................  ...........  ..........................  D4190-82(88).................  .........................  Note 34.
    Voltametry 11 or..........  ...........  ..........................  D3559-90(C)
    Colorimetric (Dithizone)..  ...........  3500-Pb D
33. Magnesium--Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration......        242.1  3111 B....................  D511-93(B)...................  I-3447-85................  974.27.\3\
    ICP/AES...................    \5\ 200.7  3120 B
    DCP, or...................  ...........  ..........................  .............................  .........................  Note 34.
    Gravimetric...............  ...........  3500-Mg D
34. Manganese--Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration \36\.        243.1  3111 B....................  D858-90(A or B)..............  I-3454-85................  974.27.\3\
    AA furnace................        243.2  3113 B....................  D858-90(C)
    ICP/AES \36\..............    \5\ 200.7  3120 B
    DCP \36\ or...............  ...........  ..........................  D4190-82(88).................  .........................  Note 34.
    Colorimetric (Persulfate),  ...........  3500-Mn D.................  .............................  .........................  920.203.\3\
     or.
    (Periodate)...............  ...........  ..........................  .............................  .........................  Note 23.
35. Mercury--Total,\4\ mg/L:
    Cold vapor, manual, or....        245.1  3112 B....................  D3223-91.....................  I-3462-85................  \3\ 977.22
    Automated.................        245.2  ..........................  .............................  .........................  .....................

[[Page 12]]

 
    Oxidation, purge and trap,    \43\ 1631  ..........................  .............................  .........................  .....................
     and cold vapor atomic
     fluorescence spectrometry
     (ng/L).
36. Molybdenum--Total,\4\ mg/
 L; Digestion \4\ followed by:
    AA direct aspiration......        246.1  3111 D....................  .............................  I-3490-85
    AA furnace................        246.2  3113 B
    ICP/AES...................    \5\ 200.7  3120 B
    DCP.......................  ...........  ..........................  .............................  .........................  Note 34.
37. Nickel--Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration \36\.        249.1  3111 B or C...............  D1886-90(A or B).............  I-3499-85
    AA furnace................        249.2  3113 B....................  D1886-90(C)
    ICP/AES \36\..............    \5\ 200.7  3120 B
    DCP \36\, or..............  ...........  ..........................  D4190-82(88).................  .........................  Note 34.
    Colorimetric (heptoxime)..  ...........  3500-Ni D
38. Nitrate (as N), mg/L:
    Colorimetric (Brucine             352.1  ..........................  .............................  .........................  973.50,\3\ 419 D,\17\
     sulfate), or Nitrate-                                                                                                          p. 28.\9\
     nitrite N minus Nitrite N
     (See parameters 39 and
     40).
39. Nitrate-nitrite (as N), mg/
 L:
    Cadmium reduction, Manual         353.3  4500-NO3- E...............  D3867-90(B)
     or.
    Automated, or.............        353.2  4500-NO3- F...............  D3867-90(A)..................  I-4545-85
    Automated hydrazine.......        353.1  4500-NO3- H
40. Nitrite (as N), mg/L;
 Spectrophotometric:
    Manual or.................        354.1  4500-NO2- B...............  .............................  .........................  Note 25.
    Automated (Diazotization).  ...........  ..........................  .............................  I-4540-85
41. Oil and grease--Total             413.1  5520 B\38\................
 recoverable, mg/L:
 Gravimetric (extraction)
    Oil and grease and non-      1664, Rev.
     polar material, mg/L:                A
     Hexane extractable
     material (HEM): n-Hexane
     extraction and
     gravimetry\42\.
    Silica gel treated HEM       1664, Rev.
     (SGT-HEM): Silica gel                A
     treatment and
     gravimetry\42\.
42. Organic carbon--Total
 (TOC), mg/L:
    Combustion or oxidation...        415.1  5310 B, C, or D...........  D2579-93 (A or B)............  .........................  973.47,3 p. 14.24
43. Organic nitrogen (as N),
 mg/L:
    Total Kjeldahl N
     (Parameter 31) minus
     ammonia N (Parameter 4)
44. Orthophosphate (as P), mg/
 L; Ascorbic acid method:
    Automated, or.............        365.1  4500-P F..................  .............................  I-4601-85................  973.56.3
    Manual single reagent.....        365.2  4500-P E..................  D515-88(A)                     .........................  973.55 3.
    Manual two reagent........        365.3
45. Osmium--Total 4, mg/L;
 Digestion 4 followed by:
    AA direct aspiration, or..        252.1  3111 D
    AA furnace................        252.2
46. Oxygen, dissolved, mg/L:
    Winkler (Azide                    360.2  4500-O C..................  D888-92(A)...................  I-1575-78 8..............  973.45B.3
     modification), or.

[[Page 13]]

 
    Electrode.................        360.1  4500-O G..................  D888-92(B)...................  I-1576-78 8
47. Palladium--Total,4 mg/L;
 Digestion 4 followed by:
    AA direct aspiration, or..        253.1  3111 B....................  .............................  .........................  p. S27.10
    AA furnace................        253.2  ..........................  .............................  .........................  p. S28.10
    DCP.......................  ...........  ..........................  .............................  .........................  Note 34.
48. Phenols, mg/L:
    Manual distillation \26\..        420.1  ..........................  .............................  .........................  Note 27.
    Followed by:
        Colorimetric (4AAP)           420.1  ..........................  .............................  .........................  Note 27.
         manual, or
        Automated \19\........        420.2
49. Phosphorus (elemental), mg/
 L:
    Gas-liquid chromatography.  ...........  ..........................  .............................  .........................  Note 28.
50. Phosphorus--Total, mg/L:
    Persulfate digestion              365.2  4500-P B,5................  .............................  .........................  973.55.\3\
     followed by.
    Manual or.................     365.2 or  4500-P E..................  D515-88(A)
                                      365.3
    Automated ascorbic acid           365.1  4500-P F..................  .............................  I-4600-85................  973.56.\3\
     reduction.
    Semi-automated block              365.4  ..........................  D515-88(B)
     digestor.
51. Platinum--Total,\4\ mg/L;
 Digestion \4\ followed by:
  AA direct aspiration........        255.1  3111 B
    AA furnace................        255.2
    DCP.......................  ...........  ..........................  .............................  .........................  Note 34.
52. Potassium--Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration......        258.1  3111 B....................  .............................  I-3630-85................  973.53.\3\
    ICP/AES...................    \5\ 200.7  3120 B
    Flame photometric, or.....  ...........  3500-K D
    Colorimetric..............  ...........  ..........................  .............................  .........................  317 B.\17\
53. Residue--Total, mg/L:
    Gravimetric, 103-105 deg..        160.3  2540 B....................  .............................  I-3750-85
54. Residue--filterable, mg/L:
    Gravimetric, 180 deg......        160.1  2540 C....................  .............................  I-1750-85
55. Residue--nonfilterable
 (TSS), mg/L:
    Gravimetric, 103-105 deg.         160.2  2540 D....................  .............................  I-3765-85
     post washing of residue.
56. Residue--settleable, mg/L:
    Volumetric, (Imhoff cone),        160.5  2540 F
     or gravimetric.
57. Residue--Volatile, mg/L:
    Gravimetric, 550 deg......        160.4  ..........................  .............................  I-3753-85
58. Rhodium--Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration, or..        265.1  3111 B
    AA furnace................        265.2
59. Ruthenium--Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration, or..        267.1  3111 B
    AA furnace................        267.2
60. Selenium--Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA furnace................        270.2  3113 B....................  D3859-93(B)
    ICP/AES,\36\ or...........    \5\ 200.7  3120 B
    AA gaseous hydride........  ...........  3114 B....................  D3859-93(A)..................  I-3667-85
61. Silica \37\--Dissolved, mg/
 L; 0.45 micron filtration
 followed by:
    Colorimetric, Manual or...        370.1  4500-Si D.................  D859-88......................  I-1700-85

[[Page 14]]

 
    Automated                   ...........  ..........................  .............................  I-2700-85
     (Molybdosilicate), or.
    ICP.......................    \5\ 200.7  3120 B
62. Silver--Total,\4\ mg/L;
 Digestion 4, 29 followed by:
    AA direct aspiration......        272.1  3111 B or C...............  .............................  I-3720-85................  974.27,\3\ p. 37.\9\
    AA furnace................        272.2  3113 B
    ICP/AES...................    \5\ 200.7  3120 B
    DCP.......................  ...........  ..........................  .............................  .........................  Note 34.
63. Sodium--Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration......        273.1  3111 B....................  .............................  I-3735-85................  973.54.\3\
    ICP/AES...................    \5\ 200.7  3120 B
    DCP, or...................  ...........  ..........................  .............................  .........................  Note 34.
    Flame photometric.........  ...........  3500 Na D
64. Specific conductance,
 micromhos/cm at 25  deg.C:
    Wheatstone bridge.........        120.1  2510 B....................  D1125-91(A)..................  I-1780-85................  973.40.\3\
65. Sulfate (as SO4), mg/L:
    Automated colorimetric            375.1
     (barium chloranilate).
    Gravimetric...............        375.3  4500-SO4-2 C or D.........  .............................  .........................  925.54.\3\
    Turbidimetric, or.........        375.4  ..........................  D516-90......................  .........................  426C.\30\
66. Sulfide (as S), mg/L:
    Titrimetric (iodine), or..        376.1  4500-S-2E.................  .............................  I-3840-85
    Colorimetric (methylene           376.2  4500-S-2D
     blue).
67. Sulfite (as SO3), mg/L:
    Titrimetric (iodine-              377.1  4500-SO3-2 B
     iodate).
68. Surfactants, mg/L:
    Colorimetric (methylene           425.1  5540 C....................  D2330-88
     blue).
69. Temperature,  deg.C:
    Thermometric..............        170.1  2550 B....................  .............................  .........................  Note 32.
70. Thallium--Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration......        279.1  3111 B
    AA furnace................        279.2
    ICP/AES, or...............    \5\ 200.7  3120 B
71. Tin--Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration......        282.1  3111 B....................  .............................  I-3850-78 \8\
    AA furnace, or............        282.2  3113 B
    ICP/AES...................    \5\ 200.7
72. Titanium--Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration......        283.1  3111 D
    AA furnace................        283.2
    DCP.......................  ...........  ..........................  .............................  .........................  Note 34.
73. Turbidity, NTU:
    Nephelometric.............        180.1  2130 B....................  D1889-88(A)..................  I-3860-85
74. Vanadium--Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration......        286.1  3111 D
    AA furnace................        286.2  ..........................  D3373-93

[[Page 15]]

 
    ICP/AES...................    \5\ 200.7  3120 B
    DCP, or...................  ...........  ..........................  D4190-82(88).................  .........................  Note 34.
    Colorimetric (Gallic acid)  ...........  3500-V D
75. Zinc--Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration \36\.        289.1  3111 B or C...............  D1691-90 (A or B)............  I-3900-85................  974.27,\3\ p. 37.\9\
    AA furnace................        289.2
    ICP/AES \36\..............    \5\ 200.7  3120 B
    DCP,\36\ or...............  ...........  ..........................  D4190-82(88).................  .........................  Note 34.
    Colorimetric (Dithizone)    ...........  3500-Zn E
     or.
    (Zincon)..................  ...........  3500-Zn F.................  .............................  .........................  Note 33.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Table IB Notes:
\1\ ``Methods for Chemical Analysis of Water and Wastes'', Environmental Protection Agency, Environmental Monitoring Systems Laboratory-Cincinnati (EMSL-
  CI), EPA-600/4-79-020, Revised March 1983 and 1979 where applicable.
\2\ Fishman, M.J., et al, ``Methods for Analysis of Inorganic Substances in Water and Fluvial Sediments,'' U.S. Department of the Interior, Techniques
  of Water--Resource Investigations of the U.S. Geological Survey, Denver, CO, Revised 1989, unless otherwise stated.
\3\ ``Official Methods of Analysis of the Association of Official Analytical Chemists,'' methods manual, 15th ed. (1990).
\4\ For the determination of total metals the sample is not filtered before processing. A digestion procedure is required to solubilize suspended
  material and to destroy possible organic-metal complexes. Two digestion procedures are given in ``Methods for Chemical Analysis of Water and Wastes,
  1979 and 1983''. One (section 4.1.3), is a vigorous digestion using nitric acid. A less vigorous digestion using nitric and hydrochloric acids
  (section 4.1.4) is preferred; however, the analyst should be cautioned that this mild digestion may not suffice for all samples types. Particularly,
  if a colorimetric procedure is to be employed, it is necessary to ensure that all organo-metallic bonds be broken so that the metal is in a reactive
  state. In those situations, the vigorous digestion is to be preferred making certain that at no time does the sample go to dryness. Samples containing
  large amounts of organic materials may also benefit by this vigorous digestion, however, vigorous digestion with concentrated nitric acid will convert
  antimony and tin to insoluble oxides and render them unavailable for analysis. Use of ICP/AES as well as determinations for certain elements such as
  antimony, arsenic, the noble metals, mercury, selenium, silver, tin, and titanium require a modified sample digestion procedure and in all cases the
  method write-up should be consulted for specific instructions and/or cautions.
Note to Table IB Note 4: If the digestion procedure for direct aspiration AA included in one of the other approved references is different than the
  above, the EPA procedure must be used.
Dissolved metals are defined as those constituents which will pass through a 0.45 micron membrane filter. Following filtration of the sample, the
  referenced procedure for total metals must be followed. Sample digestion of the filtrate for dissolved metals (or digestion of the original sample
  solution for total metals) may be omitted for AA (direct aspiration or graphite furnace) and ICP analyses, provided the sample solution to be analyzed
  meets the following criteria:
  a. has a low COD (<20)
  b. is visibly transparent with a turbidity measurement of 1 NTU or less
  c. is colorless with no perceptible odor, and
  d. is of one liquid phase and free of particulate or suspended matter following acidification.
\5\ The full text of Method 200.7, ``Inductively Coupled Plasma Atomic Emission Spectrometric Method for Trace Element Analysis of Water and Wastes,''
  is given at Appendix C of this Part 136.
\6\ Manual distillation is not required if comparability data on representative effluent samples are on company file to show that this preliminary
  distillation step is not necessary: however, manual distillation will be required to resolve any controversies.
\7\ Ammonia, Automated Electrode Method, Industrial Method Number 379-75 WE, dated February 19, 1976, (Bran & Luebbe (Technicon) Auto Analyzer II, Bran
  & Luebbe Analyzing Technologies, Inc., Elmsford, NY 10523.
\8\ The approved method is that cited in ``Methods for Determination of Inorganic Substances in Water and Fluvial Sediments'', USGS TWRI, Book 5,
  Chapter A1 (1979).
\9\ American National Standard on Photographic Processing Effluents, Apr. 2, 1975. Available from ANSI, 1430 Broadway, New York, NY 10018.
\10\ ``Selected Analytical Methods Approved and Cited by the United States Environmental Protection Agency'', Supplement to the Fifteenth Edition of
  Standard Methods for the Examination of Water and Wastewater (1981).
\11\ The use of normal and differential pulse voltage ramps to increase sensitivity and resolution is acceptable.
\12\ Carbonaceous biochemical oxygen demand (CBOD5) must not be confused with the traditional BOD5 test which measures ``total BOD''. The addition of
  the nitrification inhibitor is not a procedural option, but must be included to report the CBOD5 parameter. A discharger whose permit requires
  reporting the traditional BOD5 may not use a nitrification inhibitor in the procedure for reporting the results. Only when a discharger's permit
  specifically states CBOD5 is required can the permittee report data using the nitrification inhibitor.
\13\ OIC Chemical Oxygen Demand Method, Oceanography International Corporation, 1978, 512 West Loop, P.O. Box 2980, College Station, TX 77840.
\14\ Chemical Oxygen Demand, Method 8000, Hach Handbook of Water Analysis, 1979, Hach Chemical Company, P.O. Box 389, Loveland, CO 80537.
\15\ The back titration method will be used to resolve controversy.
\16\ Orion Research Instruction Manual, Residual Chlorine Electrode Model 97-70, 1977, Orion Research Incorporated, 840 Memorial Drive, Cambridge, MA
  02138. The calibration graph for the Orion residual chlorine method must be derived using a reagent blank and three standard solutions, containing
  0.2, 1.0, and 5.0 ml 0.00281 N potassium iodate/100 ml solution, respectively.
\17\ The approved method is that cited in Standard Methods for the Examination of Water and Wastewater, 14th Edition, 1976.
\18\ National Council of the Paper Industry for Air and Stream Improvement, (Inc.) Technical Bulletin 253, December 1971.
\19\ Copper, Biocinchoinate Method, Method 8506, Hach Handbook of Water Analysis, 1979, Hach Chemical Company, P.O. Box 389, Loveland, CO 80537.

[[Page 16]]

 
\20\ After the manual distillation is completed, the autoanalyzer manifolds in EPA Methods 335.3 (cyanide) or 420.2 (phenols) are simplified by
  connecting the re-sample line directly to the sampler. When using the mainfold setup shown in Method 335.3, the buffer 6.2 should be replaced with the
  buffer 7.6 found in Method 335.2.
\21\ Hydrogen ion (pH) Automated Electrode Method, Industrial Method Number 378-75WA, October 1976, Bran & Luebbe (Technicon) Autoanalyzer II. Bran &
  Luebbe Analyzing Technologies, Inc., Elmsford, NY 10523.
\22\ Iron, 1,10-Phenanthroline Method, Method 8008, 1980, Hach Chemical Company, P.O. Box 389, Loveland, CO 80537.
\23\ Manganese, Periodate Oxidation Method, Method 8034, Hach Handbook of Wastewater Analysis, 1979, pages 2-113 and 2-117, Hach Chemical Company,
  Loveland, CO 80537.
\24\ Wershaw, R.L., et al, ``Methods for Analysis of Organic Substances in Water,'' Techniques of Water-Resources Investigation of the U.S. Geological
  Survey, Book 5, Chapter A3, (1972 Revised 1987) p. 14.
\25\ Nitrogen, Nitrite, Method 8507, Hach Chemical Company, P.O. Box 389, Loveland, CO 80537.
\26\ Just prior to distillation, adjust the sulfuric-acid-preserved sample to pH 4 with 1 + 9 NaOH.
\27\ The approved method is cited in Standard Methods for the Examination of Water and Wastewater, 14th Edition. The colorimetric reaction is conducted
  at a pH of 10.00.2. The approved methods are given on pp 576-81 of the 14th Edition: Method 510A for distillation, Method 510B for the
  manual colorimetric procedure, or Method 510C for the manual spectophotometric procedure.
\28\ R. F. Addison and R.G. Ackman, ``Direct Determination of Elemental Phosphorus by Gas-Liquid Chromatography,'' Journal of Chromatography, vol. 47,
  No. 3, pp. 421-426, 1970.
\29\ Approved methods for the analysis of silver in industrial wastewaters at concentrations of 1 mg/L and above are inadequate where silver exists as
  an inorganic halide. Silver halides such as the bromide and chloride are relatively insoluble in reagents such as nitric acid but are readily soluble
  in an aqueous buffer of sodium thiosulfate and sodium hydroxide to pH of 12. Therefore, for levels of silver above 1 mg/L, 20 mL of sample should be
  diluted to 100 mL by adding 40 mL each of 2 M Na2S2O3 and NaOH. Standards should be prepared in the same manner. For levels of silver below 1 mg/L the
  approved method is satisfactory.
\30\ The approved method is that cited in Standard Methods for the Examination of Water and Wastewater, 15th Edition.
\31\ EPA Methods 335.2 and 335.3 require the NaOH absorber solution final concentration to be adjusted to 0.25 N before colorimetric determination of
  total cyanide.
\32\ Stevens, H.H., Ficke, J.F., and Smoot, G.F., ``Water Temperature--Influential Factors, Field Measurement and Data Presentation'', Techniques of
  Water-Resources Investigations of the U.S. Geological Survey, Book 1, Chapter D1, 1975.
\33\ Zinc, Zincon Method, Method 8009, Hach Handbook of Water Analysis, 1979, pages 2-231 and 2-333, Hach Chemical Company, Loveland, CO 80537.
\34\ ``Direct Current Plasma (DCP) Optical Emission Spectrometric Method for Trace Elemental Analysis of Water and Wastes, Method AES0029,'' 1986--
  Revised 1991, Fison Instruments, Inc., 32 Commerce Center, Cherry Hill Drive, Danvers, MA 01923.
\35\ Precision and recovery statements for the atomic absorption direct aspiration and graphite furnace methods, and for the spectrophotometric SDDC
  method for arsenic are provided in Appendix D of this part titled, ``Precision and Recovery Statements for Methods for Measuring Metals''.
\36\ ``Closed Vessel Microwave Digestion of Wastewater Samples for Determination of Metals'', CEM Corporation, P.O. Box 200, Matthews, NC 28106-0200,
  April 16, 1992. Available from the CEM Corporation.
\37\ When determining boron and silica, only plastic, PTFE, or quartz laboratory ware may be used from start until completion of analysis.
\38\ Only the trichlorofluoromethane extraction solvent is approved.
\39\ Nitrogen, Total Kjeldahl, Method PAI-DK01 (Block Digestion, Steam Distillation, Titrimetric Detection), revised 12/22/94, Perstop Analytical
  Corporation.
\40\ Nitrogen, Total Kjeldahl, Method PAI-DK02 (Block Digestion, Steam Distillation, Colorimetric Detection), revised 12/22/94, Perstop Analytical
  Corporation.
\41\ Nitrogen, Total Kjeldahl, Method PAI-DK03 (Block Digestion, Automated FIA Gas Diffusion), revised 12/22/94, Perstop Analytical Corporation.
\42\ Method 1664, Revision A ``n-Hexane Extractable Material (HEM; Oil and Grease) and Silica Gel Treated n-Hexane Extractablke Material (SGT-HEM; Non-
  polar Material) by Extraction and Gravimetry'' EPA-821-R-98-002, February 1999. Available at NTIS, PB-121949, U.S. Department of Commerce, 5285 Port
  Royal, Springfield, Virginia 22161.
\43\ The application of clean techniques described in EPA's draft Method 1669: Sampling Ambient Water for Trace Metals at EPA Water Quality Criteria
  Levels (EPA-821-R-96-011) are recommended to preclude contamination at low-level, trace metal determinations.
\44\ Available Cyanide, Method OIA-1677 (Available Cyanide by Flow Injection, Ligand Exchange, and Amperometry), ALPKEM, A Division of OI Analytical,
  P.O. Box 9010, College Station, TX 77842-9010.


                                     Table IC.--List of Approved Test Procedures for Non-Pesticide Organic Compounds
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                 EPA method number 2 7
        Parameter \1\         --------------------------------------------------------------------------------------------------------------------------
                                       GC                 GC/MS           HPLC         Standard method 18th Ed.              ASTM              Other
--------------------------------------------------------------------------------------------------------------------------------------------------------
 1. Acenaphthene.............                 610           625, 1625        610  6410 B, 6440 B                     D4657-92
 2. Acenaphthylene...........                 610           625, 1625        610  6410 B, 6440 B                     D4657-92
 3. Acrolein.................                 603       \4\ 604, 1624  .........  .................................  ....................
 4. Acrylonitrile............                 603       \4\ 624, 1624        610  .................................  ....................
 5. Anthracene...............                 610           625, 1625        610  6410 B, 6440 B                     D4657-92
 6. Benzene..................                 602           624, 1624  .........  6210 B, 6220 B                     ....................
 7. Benzidine................  ..................       \5\ 625, 1625        605  .................................  ....................  Note 3, p.1.
 8. Benzo(a)anthracene.......                 610           625, 1625        610  6410 B, 6440 B                     D4657-92
 9. Benzo(a)pyrene...........                 610           625, 1625        610  6410 B, 6440 B                     D4657-92

[[Page 17]]

 
 10. Benzo(b)fluoranthene....                 610           625, 1625        610  6410 B, 6440 B                     D4657-92
 11. Benzo(g, h, i)perylene..                 610           625, 1625        610  6410 B, 6440 B                     D4657-92
 12. Benzo(k)fluoranthene....                 610           625, 1625        610  6410 B, 6440 B                     D4657-92
 13. Benzyl chloride.........  ..................  ..................  .........  .................................  ....................  Note 3,
                                                                                                                                            p.130: Note
                                                                                                                                            6, p. S102.
 14. Benzyl butyl phthalate..                 606           625, 1625  .........  6410 B                             ....................  .............
 15. Bis(2-chloroethoxy)                      611           625, 1625  .........  6410 B                             ....................
 methane.
 16. Bis(2-chloroethyl) ether                 611           625, 1625  .........  6410 B                             ....................
 17. Bis (2-ethylhexyl)                       606           625, 1625  .........  6410 B, 6230 B                     ....................
 phthalate.
 18. Bromodichloromethane....                 601           624, 1624  .........  6210 B, 6230 B                     ....................
 19. Bromoform...............                 601           624, 1624  .........  6210 B, 6230 B                     ....................
 20. Bromomethane............                 601           624, 1624  .........  6210 B, 6230 B                     ....................
 21. 4-Bromophenylphenyl                      611           625, 1625  .........  6410 B                             ....................
 ether.
 22. Carbon tetrachloride....                 601           624, 1624  .........  6230 B, 6410 B                     ....................  Note 3,
                                                                                                                                            p.130.
 23. 4-Chloro-3-methylphenol.                 604           625, 1625  .........  6410 B, 6420 B                     ....................
 24. Chlorobenzene...........            601, 602           624, 1624  .........  6210 B, 6220 B                     ....................  Note 3,
                                                                                  6230 B                                                    p.130.
 25. Chloroethane............                 601           624, 1624  .........  6210 B, 6230 B                     ....................
 26. 2-Chloroethylvinyl ether                 601           624, 1624  .........  6210 B, 6230 B                     ....................  .............
 27. Chloraform..............                 601           624, 1624  .........  6210 B, 6230 B                     ....................  Note, p.130.
 28. Chloromethane...........                 601           624, 1624  .........  6210 B. 6230 B                     ....................
 29. 2-Chloronaphthalene.....                 612           625, 1625  .........  6410 B                             ....................
 30. 2-Chlorophenol..........                 604           625, 1625  .........  6410 B, 6420 B                     ....................
 31. 4-Chlorophenylphenyl                     611           625, 1625  .........  6410 B                             ....................
 ether.
 32. Chrysene................                 610           625, 1625        610  6410 B, 6440 B                     D4657-92
 33. Dibenzo(a,h)anthracene..                 610           625, 1625        610  6410 B, 6440 B                     D4657-92
 34. Dibromochloromethane....                 601           624, 1624  .........  6210 B, 6230 B                     ....................
 35. 1, 2-Dichlorobenzene....         601,602,612        624,625,1625  .........  6410 B, 6230 B, 6220 B             ....................
 36. 1, 3-Dichlorobenzene....         601,602,612        624,625,1625  .........  6410 B, 6230 B, 6220 B             ....................
 37. 1,4-Dichlorobenzene.....       601, 602, 612      624, 625, 1625  .........  6410 B, 6220 B, 6230 B
 38. 3, 3-Dichlorobenzidine..  ..................           625, 1625        605  6410 B                             ....................
 39. Dichlorodifluoromethane.                 601  ..................  .........  6230 B                             ....................
 40. 1, 1-Dichloroethane.....                 601           624, 1624  .........  6230 B, 6210 B                     ....................
 41. 1, 2-Dichloroethane.....                 601           624, 1624  .........  6230 B, 6210 B                     ....................
 42. 1, 1-Dichloroethene.....                 601           624, 1624  .........  6230 B, 6210 B                     ....................
 43. trans-1, 2-                              601           624, 1624  .........  6230 B, 6210 B                     ....................
 Dichloroethene.
 44. 2, 4-Dichlorophenol.....                 604           625, 1625  .........  6420 B, 6410 B                     ....................
 45. 1, 2-Dichloropropane....                 601           624, 1624  .........  6230 B, 6210 B                     ....................
 46. cis-1, 3-Dichloropropene                 601           624, 1624  .........  6230 B, 6210 B                     ....................
 47. trans-1, 3-                              601           624, 1624  .........  6230 B, 6210 B                     ....................
 Dichloropropene.
 48. Diethyl phthalate.......                 606           625, 1625  .........  6410 B                             ....................
 49. 2, 4-Dimethylphenol.....                 604           625, 1625  .........  6420 B, 6410 B                     ....................
 50. Dimethyl phthalate......                 606           625, 1625  .........  6410 B                             ....................
 51. Di-n-butyl phthalate....                 606           625, 1625  .........  6410 B                             ....................
 52. Di-n-octyl phthalate....                 606           625, 1625  .........  6410 B                             ....................
 53. 2,4-Dinitrophenol.......                 604           625, 1625  .........  6420 B, 6410 B                     ....................
 54. 2,4-Dinitrotoluene......                 609           625, 1625  .........  6410 B
 55. 2, 6-Dinitrotoluene.....                 609           625, 1625  .........  6410 B                             ....................

[[Page 18]]

 
 56. Epichlorohydrin.........  ..................  ..................  .........  .................................  ....................  Note 3, p.130
                                                                                                                                            Note 6,
                                                                                                                                            p.S102.
 57. Ethylbenzene............                 602           624, 1624  .........  6220 B, 6210 B                     ....................
 58. Fluoranthene............                 610           625, 1625        610  6410 B, 6440 B                     D4657-92
 59. Fluorene................                 610           625, 1625        610  6410 B, 6440 B                     D4657-92
 60. 1,2,3,4,6,7,8-            ..................                1613  .........
 Heptachlorodibenzofuran.
 61. 1,2,3,4,7,8,9-            ..................                1613  .........
 Heptachlorodibenzofuran.
 62. 1,2,3,4,6,7,8-            ..................                1613  .........
 Heptachlorodibenzo-p-dioxin.
 63. Hexachlorobenzene.......                 612           625, 1625  .........  6410 B
 64. Hexachlorobutadiene.....                 612           625, 1625  .........  6410 B
 65.                                          612       625, 1625 \5\  .........  6410 B
 Hexachlorocyclopentadiene.
 66. 1,2,3,4,7,8-              ..................                1613  .........
 Hexachlorodibenzofuran.
 67. 1,2,3,6,7,8-              ..................                1613  .........
 Hexachlorodibenzofuran.
 68. 1,2,3,7,8,9-              ..................                1613  .........
 Hexachlorodibenzofuran.
 69. 2,3,4,6,7,8-              ..................                1613  .........
 Hexachlorodibenzofuran.
 70. 1,2,3,4,7,8-              ..................                1613  .........
 Hexachlorodibenzo-p-dioxin.
 71. 1,2,3,6,7,8-              ..................                1613  .........
 Hexachlorodibenzo-p-dioxin.
 72. 1,2,3,7,8,9-              ..................                1613  .........
 Hexachlorodibenzo-p-dioxin.
 73. Hexachloroethane........                 616           625, 1625  .........  6410 B
 74. Ideno(1,2,3-cd)pyrene...                 610           625, 1625        610  6410 B, 6440 B                     D4657-87
 75. Isophorone..............                 609           625, 1625  .........  6410 B
 76. Methylene chloride......                 601           624, 1624  .........  6230 B                                                   Note 3, p.
                                                                                                                                            130.
 77. 2-Methyl-4,6-                            604           625, 1625  .........  6420 B, 6410 B
 dinitrophenol.
 78. Naphthalene.............                 610           625, 1625        610  6410 B, 6440 B
 79. Nitrobenzene............                 609           625, 1625  .........  6410 B                             D4657-87
 80. 2-Nitrophenol...........                 604           625, 1625  .........  6410 B, 6420 B
 81. 4-Nitrophenol...........                 604           625, 1625  .........  6410 B, 6420 B
 82. N-Nitrosodimethylamine..                 607           625, 1625  .........  6410 B
 83. N-Nitrosodi-n-                           607       625, 1625 \5\  .........  6410 B
 propylamine.
 84. N-Nitrosodiphenylamine..                 607       625, 1625 \5\  .........  6410 B
 85. Octachlorodibenzofuran..  ..................                1613  .........
 86. Octachlorodibenzo-p-      ..................                1613  .........
 dioxin.
 87. 2,2-Oxybis(1-                            611           625, 1625  .........  6410 B
 chloropropane).
 88. PCB-1016................                 608                 625  .........  6410 B                                                   Note 3, p.
                                                                                                                                            43.
 89. PCB-1221................                 608                 625  .........  6410 B                                                   Note 3, p.
                                                                                                                                            43.
 90. PCB-1232................                 608                 625  .........  6410 B                                                   Note 3, p.
                                                                                                                                            43.
 91. PCB 1242................                 608                 625  .........  6410 B                                                   Note 3, p.
                                                                                                                                            43.
 92. PCB-1248................                 608                 625  .........
 93. PCB-1254................                 608                 625  .........  6410 B                                                   Note 3, p.
                                                                                                                                            43.
 94. PCB-1260................                 608                 625  .........  6410 B, 6630 B                                           Note 3, p.
                                                                                                                                            43.
 95. 1,2,3,7,8-                ..................                1613  .........
 Pentachlorodibenzofuran.
 96. 2,3,4,7,8-                ..................                1613  .........
 Pentachlorodibenzofuran.
 97. 1,2,3,7,8-                ..................                1613  .........
 Pentachlorodibenzo-p-dioxin.

[[Page 19]]

 
 98. Pentachlorophenol                        604           625, 1625  .........  6410 B, 6630 B                                           Note 3, p.
                                                                                                                                            140.
 99. Phenanthrene............                 610           625, 1625        610  6410 B, 6440 B                     D4657-87
 100. Phenol.................                 604           625, 1625  .........  6420 B, 6410 B
 101. Pyrene.................                 610           625, 1625        610  6410 B, 6440 B                     D4657-87
 102. 2,3,7,8-                 ..................                1613  .........
 Tetrachlorodibenzofuran.
 103. 2,3,7,8-                 ..................       613, 1613 \5\  .........
 Tetrachlorodibenzo-p-dioxin.
 104. 1,1,2,2-                                601           624, 1624  .........  6230 B, 6210 B                                           Note 3, p.
 Tetrachloroethane.                                                                                                                         130.
 105. Tetrachloroethene......                 601           624, 1624  .........  6230 B, 6410 B                                           Note 3, p.
                                                                                                                                            130.
 106. Toluene................                 602           624, 1624  .........  6210 B, 6220 B
 107. 1,2,4-Trichlorobenzene.                 612           625, 1625  .........  6410 B                                                   Note 3, p.
                                                                                                                                            130.
 108. 1,1,1-Trichloroethane..                 601           624, 1624  .........  6210 B, 6230 B
 109. 1,1,2-Trichloroethane..                 601           624, 1624  .........  6210 B, 6230 B                                           Note 3, p.
                                                                                                                                            130.
 110. Trichloroethene........                 601           624, 1624  .........  6210 B, 6230 B
 111. Trichlorofluoromethane.                 601                 624  .........  6210 B, 6230 B
 112. 2,4,6-Trichlorophenol..                 604           625, 1625  .........  6410 B, 6240 B
 113. Vinyl chloride.........                 601           624, 1624  .........  6210 B, 6230 B
--------------------------------------------------------------------------------------------------------------------------------------------------------
Table 1C notes:
\1\ All parameters are expressed in micrograms per liter ([mu]g/L) except for Method 1613 in which the parameters are expressed in picograms per liter
  (pg/L).
\2\ The full text of Methods 601-613, 624, 625, 1624, and 1625, are given at appendix A, ``Test Procedures for Analysis of Organic Pollutants,'' of this
  part 136. The full text of Method 1613 is incorporated by reference into this part 136 and is available from the National Technical Information
  Services as stock number PB95-104774. The standardized test procedure to be used to determine the method detection limit (MDL) for these test
  procedures is given at appendix B, ``Definition and Procedures for the Determination of the Method Detection Limit,'' of this part 136.
\3\ ``Methods for Benzidine: Chlorinated Organic Compounds, Pentachlorophenol and Pesticides in Water and Wastewater,'' U.S. Environmental Protection
  Agency, September, 1978.
\4\ Method 624 may be extended to screen samples for Acrolein and Acrylonitrile. However, when they are known to be present, the preferred method for
  these two compounds is Method 603 or Method 1624.
\5\ Method 625 may be extended to include benzidine, hexachlorocyclopentadiene, N-nitrosodimethylamine, and N-nitrosodiphenylamine. However, when they
  are known to be present, Methods 605, 607, and 612, or Method 1625, are preferred methods for these compounds.
5a 625, Screening only.
\6\ ``Selected Analytical Methods Approved and Cited by the United States Environmental Protection Agency'', Supplement to the Fifteenth Edition of
  Standard Methods for the Examination of Water and Wastewater (1981).
\7\ Each Analyst must make an initial, one-time demonstration of their ability to generate acceptable precision and accuracy with Methods 601-603, 624,
  625, 1624, and 1625 (See Appendix A of this Part 136) in accordance with procedures each in section 8.2 of each of these Methods. Additionally, each
  laboratory, on an on-going basis must spike and analyze 10% (5% for Methods 624 and 625 and 100% for methods 1624 and 1625) of all samples to monitor
  and evaluate laboratory data quality in accordance with sections 8.3 and 8.4 of these Methods. When the recovery of any parameter falls outside the
  warning limits, the analytical results for that parameter in the unspiked sample are suspect and cannot be reported to demonstrate regulatory
  compliance.
Note: These warning limits are promulgated as an ``interim final action with a request for comments.''
\8\ ``Organochlorine Pesticides and PCBs in Wastewater Using Empore TM Disk'', 3M Corporation Revised 10/28/94.


                                              Table ID.--List of Approved Test Procedures for Pesticides 1
--------------------------------------------------------------------------------------------------------------------------------------------------------
            Parameter                        Method           EPA \2\ \7\  Standard methods 18th Ed.            ASTM                      Other
--------------------------------------------------------------------------------------------------------------------------------------------------------
1. Aldrin........................  GC                                 608  6630 B & C...............  D3086-90................  Note 3, p. 7; note 4, p.
                                                                                                                                 30; note 8.
                                   GC/MS                              625  6410 B...................  ........................  ........................
2. Ametryn.......................  GC                         ...........  .........................  ........................  Note 3, p. 83; Note 6,
                                                                                                                                 p. S68.
3. Aminocarb.....................  TLC                        ...........  .........................  ........................  Note 3, p. 94; Note 6,
                                                                                                                                 p. S16.
4. Atraton.......................  GC                         ...........  .........................  ........................  Note 3, p. 83; Note 6,
                                                                                                                                 p. S68.
5. Atrazine......................  GC                         ...........  .........................  ........................  Note 3, p. 83; Note 6,
                                                                                                                                 p. S68.
6. Azinphos methyl...............  GC                         ...........  .........................  ........................  Note 3, p. 25; Note 6,
                                                                                                                                 p. S51.
7. Barban........................  TLC                        ...........  .........................  ........................  Note 3, p. 104; Note 6,
                                                                                                                                 p. S64.
8. [alpha]-BHC...................  GC                                 608  6630 B & C...............  D3086-90................  Note 3, p. 7; note 8.
                                   GC/MS                          \5\ 625  6410 B...................  ........................  ........................

[[Page 20]]

 
9. [beta]-BHC....................  GC                                 608  6630 C...................  D3086-90................  Note 8.
                                   GC/MS                          \5\ 625  6410 B...................  ........................  ........................
10. [delta]-BHC..................  GC                                 608  6630 C...................  D3086-90................  Note 8.
                                   GC/MS                          \5\ 625  6410 B...................  ........................  ........................
11. [delta]-BHC (Lindane)........  GC                                 608  6630 B & C...............  D3086-90................  Note 3, p. 7; note 4, p.
                                                                                                                                 30; note 8.
                                   GC/MS                              625  6410 B...................  ........................  ........................
 
12. Captan.......................  GC                         ...........  6630 B                     D3086-90                  Note 3, p. 7.
13. Carbaryl.....................  TLC                        ...........  .........................  ........................  Note 3, p. 94: Note 6,
                                                                                                                                 p. S60.
14. Carbophenothion..............  GC                         ...........  .........................  ........................  Note 4, p. 30; Note 6,
                                                                                                                                 p. S73.
15. Chlordane....................  GC                                 608  6630 B & C...............  D3086-90................  Note 3, p. 7; note 8.
                                   GC/MS                              625  6410 B...................  ........................  ........................
 
16. Chloropropham................  TLC                        ...........  .........................  ........................  Note 3, p. 104; Note 6,
                                                                                                                                 p. S64.
17. 2,4-D........................  GC                         ...........  6640 B...................  ........................  Note 3, p. 115; Note 4,
                                                                                                                                 p. 35.
18. 4,4'-DDD.....................  GC                                 608  6630 B & C...............  D3086-90................  Note 3, p. 7; note 4, p.
                                                                                                                                 30; note 8.
                                   GC/MS                              625  6410 B...................  ........................  ........................
19. 4,4'-DDE.....................  GC                                 608  6630 B & C...............  D3086-90................  Note 3, p. 7; note 4, p.
                                                                                                                                 30; note 8.
                                   GC/MS                              625  6410 B...................  ........................  ........................
20. 4,4'-DDT.....................  GC                                 608  6630 B & C...............  D3086-90................  Note 3, p. 7; note 4, p.
                                                                                                                                 30; note 8.
                                   GC/MS                              625  6410 B...................  ........................  ........................
 
21. Demeton-O....................  GC                         ...........  .........................  ........................  Note 3, p. 25; Note 6,
                                                                                                                                 p. S51.
22. Demeton-S....................  GC                         ...........  .........................  ........................  Note 3, p. 25: Note 6,
                                                                                                                                 p. S51.
23. Diazinon.....................  GC                         ...........  .........................  ........................  Note 3, p. 25; Note 4,
                                                                                                                                 p. 30; Note 6, p. S51.
24. Dicamba......................  GC                         ...........  .........................  ........................  Note 3, p. 115.
25. Dichlofenthion...............  GC                         ...........  .........................  ........................  Note 4, p. 30; Note 6,
                                                                                                                                 p. S73.
26. Dichloran....................  GC                         ...........  6630 B & C...............  ........................  Note 3, p. 7.
27. Dicofol......................  GC                         ...........  .........................  D3086-90................  ........................
28. Dieldrin.....................  GC                                 608  6630 B & C...............  ........................  Note 3, p. 7; note 4, p.
                                                                                                                                 30; note 8.
                                   GC/MS                              625  6410 B...................  ........................  ........................
 
29. Dioxathion...................  GC                         ...........  .........................  ........................  Note 4, p. 30; Note 6,
                                                                                                                                 p. S73.
30. Disulfoton...................  GC                         ...........  .........................  ........................  Note 3, p. 25; Note 6,
                                                                                                                                 p. S51.
31. Diuron.......................  TLC                        ...........  .........................  ........................  Note 3, p. 104; Note 6,
                                                                                                                                 p. S64.
32. Endosulfan I.................  GC                                 608  6630 B & C...............  D3086-90................  Note 3, p. 7; note 8.
                                   GC/MS                          \5\ 625  6410 B...................  ........................  ........................
33. Endosulfan II................  GC                                 608  6630 B & C...............   D3086-90...............  Note 3, p. 7; note 8.
                                   GC/MS                          \5\ 625  6410 B...................  ........................  ........................
34. Endosulfan Sulfate...........  GC                                 608  6630 C...................  ........................  Note 8.
                                   GC/MS                              625  6410 B...................  ........................  ........................
35. Endrin.......................  GC                                 608  6630 B & C...............  D3086-90................  Note 3, p. 7; note 4, p.
                                                                                                                                 30; note 8.
                                   GC/MS                          \5\ 625  6410 B...................  ........................  ........................
36. Endrin aldehyde..............  GC                                 608  .........................  ........................  Note 8.
                                   GC/MS                              625  .........................  ........................  ........................

[[Page 21]]

 
 
37. Ethion.......................  GC                         ...........  .........................  ........................  Note 4, p. 30; Note 6,
                                                                                                                                 p. S73.
38. Fenuron......................  TLC                        ...........  .........................  ........................  Note 3, p. 104; Note 6,
                                                                                                                                 p. S64.
39. Fenuron-TCA..................  TLC                        ...........  .........................  ........................  Note 3, p. 104; Note 6,
                                                                                                                                 p. S64.
40. Heptachlor...................  GC                                 608  6630 B & C...............  D3086-90................  Note 3, p. 7; note 4, p.
                                                                                                                                 30; note 8.
                                   GC/MS                              625  6410 B...................  ........................  ........................
41. Heptachlor epoxide...........  GC                                 608  6630 B & C...............  D3086-90................  Note 3, p. 7; note 4, p.
                                                                                                                                 30; note 6, p. S73;
                                                                                                                                 note 8.
                                   GC/MS                              625  6410 B...................  ........................  ........................
 
42. Isodrin......................  GC                         ...........  .........................  ........................  Note 4, p. 30; Note 6,
                                                                                                                                 p. S73.
43. Linuron......................  GC                         ...........  .........................  ........................  Note 3, p. 104; Note 6,
                                                                                                                                 p. S64.
44. Malathion....................  GC                         ...........  6630 C...................  ........................  Note 3, p. 25; Note 4,
                                                                                                                                 p. 30; Note 6, p. S51.
45. Methiocarb...................  TLC                        ...........  .........................  ........................  Note 3, p. 94; Note 6,
                                                                                                                                 p. S60.
46. Methoxychlor.................  GC                         ...........  6630 B & C...............  D3086-90................  Note 3, p. 7; note 4, p.
                                                                                                                                 30; note 8.
 
47. Mexacarbate..................  TLC                        ...........  .........................  ........................  Note 3, p. 94; Note 6,
                                                                                                                                 p. S60.
48. Mirex........................  GC                         ...........  6630 B & C...............  ........................  Note 3, p. 7.
49. Monuron......................  TLC                        ...........  .........................  ........................  Note 3, p. 104; Note 6,
                                                                                                                                 p. S64.
50. Monuron......................  TLC                        ...........  .........................  ........................  Note 3, p. 104; Note 6,
                                                                                                                                 p. S64.
51. Nuburon......................  TLC                        ...........  .........................  ........................  Note 3, p. 104; Note 6,
                                                                                                                                 p. S64.
52. Parathion methyl.............  GC                         ...........  6630 C...................  ........................  Note 3, p. 25; Note 4,
                                                                                                                                 p. 30.
53. Parathion ethyl..............  GC                         ...........  6630 C...................  ........................  Note 3, p. 25.
54. PCNB.........................  GC                         ...........  6630 B & C...............  ........................  Note 3, p. 7.
55. Perthane.....................  GC                         ...........  .........................  D3086-90................  ........................
56. Prometron....................  GC                         ...........  .........................  ........................  Note 3, p. 83; Note 6,
                                                                                                                                 p. S68.
57. Prometryn....................  GC                         ...........  .........................  ........................  Note 3, p. 83; Note 6,
                                                                                                                                 p. S68.
58. Propazine....................  GC                         ...........  .........................  ........................  Note 3, p. 83; Note 6,
                                                                                                                                 p. S68.
59. Propham......................  TLC                        ...........  .........................  ........................  Note 3, p. 104; Note 6,
                                                                                                                                 p. S64.
60. Propoxur.....................  TLC                        ...........  .........................  ........................  Note 3, p. 94; Note 6,
                                                                                                                                 p. S60.
61. Secbumeton...................  TLC                        ...........  .........................  ........................  Note 3, p. 83; Note 6,
                                                                                                                                 p. S68.
62. Siduron......................  TLC                        ...........  .........................  ........................  Note 3, p. 104; Note 6,
                                                                                                                                 p. S64.
63. Simazine.....................  GC                         ...........  .........................  ........................  Note 3, p. 83; Note 6,
                                                                                                                                 p. S68.
64. Strobane.....................  GC                         ...........  6630 B & C...............  ........................  Note 3, p. 7.
65. Swep.........................  TLC                        ...........  .........................  ........................  Note 3, p. 104; Note 6,
                                                                                                                                 p. S64.
66. 2,4,5-T......................  GC                         ...........  6640 B...................  ........................  Note 3, p. 115; Note 4,
                                                                                                                                 p. 35.
67. 2,4,5-TP (Silvex)............  GC                         ...........  6640 B...................  ........................  Note 3, p. 115
68. Terbuthylazine...............  GC                         ...........  .........................  ........................  Note 3, p. 83; Note 6,
                                                                                                                                 p. S68.
69. Toxaphene....................  GC                                 608  6630 B & C...............  D3086-90................  Note 3, p. 7; note 4, p.
                                                                                                                                 30; note 8.
                                   GC/MS                              625  6410 B...................  ........................  ........................
70. Trifluralin..................  GC                         ...........  6630 B...................  ........................  Note 3, p. 7.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Table ID notes:
\1\ Pesticides are listed in this table by common name for the convenience of the reader. Additional pesticides may be found under Table 1C, where
  entries are listed by chemical name.
\2\ The full text of Methods 608 and 625 are given at Appendix A. ``Test Procedures for Analysis of Organic Pollutants,'' of this Part 136. The
  standardized test procedure to be used to determine the method detection limit (MDL) for these test procedures is given at Appendix B. ``Definition
  and Procedure for the Determination of the Method Detection Limit'', of this Part 136.
\3\ ``Methods for Benzidine, Chlorinated Organic Compounds, Pentachlorophenol and Pesticides in Water and Wastewater,'' U.S. Environmental Protection
  Agency, September, 1978. This EPA publication includes thin-layer chromatography (TLC) methods.
\4\ ``Methods for Analysis of Organic Substances in Water and Fluvial Sediments,'' Techniques of Water-Resources Investigations of the U.S. Geological
  Survey, Book 5, Chapter A3 (1987).
\5\ The method may be extended to include [alpha]-BHC, [gamma]-BHC, endosulfan I, endosulfan II, and endrin. However, when they are known to exist,
  Method 608 is the preferred method.
\6\ ``Selected Analytical Methods Approved and Cited by the United States Environmental Protection Agency.'' Supplement to the Fifteenth Edition of
  Standard Methods for the Examination of Water and Wastewater (1981).

[[Page 22]]

 
\7\ Each analyst must make an initial, one-time, demonstration of their ability to generate acceptable precision and accuracy with Methods 608 and 625
  (See Appendix A of this Part 136) in accordance with procedures given in section 8.2 of each of these methods. Additionally, each laboratory, on an-
  going basis, must spike and analyze 10% of all samples analyzed with Method 608 or 5% of all samples analyzed with Method 625 to monitor and evaluate
  laboratory data quality in accordance with Sections 8.3 and 8.4 of these methods. When the recovery of any parameter falls outside the warning limits,
  the analytical results for that parameter in the unspiked sample are suspect and cannot be reported to demonstrate regulatory compliance. These
  quality control requirements also apply to the Standard Methods, ASTM Methods, and other Methods cited.
Note: These warning limits are promulgated as an ``Interim final action with a request for comments.''
\8\ ``Organochlorine Pesticides and PCBs in Wastewater Using EmporeTM Disk'', 3M Corporation, Revised 10/28/94.


                                                 Table IE.--List of Approved Radiologic Test Procedures
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                          Reference (method number or page)
                                                           ---------------------------------------------------------------------------------------------
       Parameter and units                 Method                                     Standard methods
                                                                    EPA\1\                18th Ed.                ASTM                  USGS \2\
--------------------------------------------------------------------------------------------------------------------------------------------------------
1. Alpha-Total, pCi per liter...  Proportional or           900...................  7110 B                D1943-90              pp. 75 and 78.\3\
                                   scintillation counter.
2. Alpha-Counting error, pCi per  Proportional or           Appendix B............  7110 B                D1943-90              P. 79.
 liter.                            scintillation counter.
3. Beta-Total, pCi per liter....  Proportional counter....  900.0.................  7110 B                D1890-90              pp. 75 and 78.\3\
4. Beta-Counting error, pCi.....  Proportional counter....  Appendix B............  7110 B                D1890-90              p. 79.
5. (a) Radium Total pCi per       Proportional counter....  903.0.................  7500Ra B              D2460-90
 liter.
  (b)Ra, pCi per liter..........  Scintillation counter...  903.1.................  7500Ra C              D3454-91              p. 81.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Table IE notes:
\1\ Prescribed Procedures for Measurement of Radioactivity in Drinking Water,'' EPA-600/4-80-032 (1980), U.S. Environmental Protection Agency, August
  1980.
\2\ Fishman, M.J. and Brown, Eugene,'' Selected Methods of the U.S. Geological Survey of Analysis of Wastewaters,'' U.S. Geological Survey, Open-File
  Report 76-177 (1976).
\3\ The method found on p. 75 measures only the dissolved portion while the method on p. 78 measures only the suspended portion. Therefore, the two
  results must be added to obtain the ``total''.


[[Page 23]]


                        Table IF.--List of Approved Methods for Pharmaceutical Pollutants
----------------------------------------------------------------------------------------------------------------
   Pharmaceuticals pollutants              CAS registry No.                    Analytical method number
----------------------------------------------------------------------------------------------------------------
acetonitrile...................  75-05-8............................  1666/1671/D3371/D3695.
n-amyl acetate.................  628-63-7...........................  1666/D3695.
n-amyl alcohol.................  71-41-0............................  1666/D3695
benzene........................  71-43-2............................  D4763/D3695/502.2/524.2.
n-butyl-acetate................  123-86-4...........................  1666/D3695.
tert-butyl alcohol.............  75-65-0............................  1666.
chlorobenzene..................  108-90-7...........................  502.2/524.2.
chloroform.....................  67-66-3............................  502.2/524.2/551.
o-dichlorobenzene..............  95-50-1............................  1625C/502.2/524.2.
1,2-dichloroethane.............  107-06-2...........................  D3695/502.2/524.2.
diethylamine...................  109-89-7...........................  1666/1671.
dimethyl sulfoxide.............  67-68-5............................  1666/1671.
ethanol........................  64-17-5............................  1666/1671/D3695.
ethyl acetate..................  141-78-6...........................  1666/D3695.
n-heptane......................  142-82-5...........................  1666/D3695.
n-hexane.......................  110-54-3...........................  1666/D3695.
isobutyraldehyde...............  78-84-2............................  1666/1667.
isopropanol....................  67-63-0............................  1666/D3695.
isopropyl acetate..............  108-21-4...........................  1666/D3695.
isopropyl ether................  108-20-3...........................  1666/D3695.
methanol.......................  67-56-1............................  1666/1671/D3695.
Methyl Cellosolve [Delta]......  109-86-4...........................  1666/1671
methylene chloride.............  75-09-2............................  502.2/524.2
methyl formate.................  107-31-3...........................  1666.
4-methyl-2-pentanone (MIBK)....  108-10-1...........................  1624C/1666/D3695/D4763/524.2.
phenol.........................  108-95-2...........................  D4763.
n-propanol.....................  71-23-8............................  1666/1671/D3695.
2-propanone (acetone)..........  67-64-1............................  D3695/D4763/524.2.
tetrahydrofuran................  109-99-9...........................  1666/524.2.
toluene........................  108-88-3...........................  D3695/D4763/502.2/524.2.
triethlyamine..................  121-44-8...........................  1666/1671.
xylenes........................  (Note 1)...........................  1624C/1666.
----------------------------------------------------------------------------------------------------------------
Table 1F note:
1. 1624C: m-xylene 108-38-3, o,p-xylene E-14095 (Not a CAS number; this is the number provided in the
  Environmental Monitoring Methods Index (EMMI) database.); 1666: m,p-xylene 136777-61-2, o-xylene 95-47-6.

    (b) The full texts of the methods from the following references 
which are cited in Tables IA, IB, IC, ID, IE,and IF are incorporated by 
reference into this regulation and may be obtained from the sources 
identified. All costs cited are subject to change and must be verified 
from the indicated sources. The full texts of all the test procedures 
cited are available for inspection at the National Exposure Research 
Laboratory, Office of Research and Development, U.S. Environmental 
Protection Agency, 26 West Martin Luther King Dr., Cincinnati, OH 45268 
and the Office of the Federal Register, 800 North Capitol Street, NW., 
Suite 700, Washington, DC.

            References, Sources, Costs, and Table Citations:

    (1) The full texts of Methods 601-613, 624, 625, 1613, 1624, and 
1625 are printed in appendix A of this part 136. The full text for 
determining the method detection limit when using the test procedures is 
given in appendix B of this part 136. The full text of Method 200.7 is 
printed in appendix C of this part 136. Cited in: Table IB, Note 5; 
Table IC, Note 2; and Table ID, Note 2.
    (2) USEPA. 1978. Microbiological Methods for Monitoring the 
Environment, Water, and Wastes. Environmental Monitoring and Support 
Laboratory, U.S. Environmental Protection Agency, Cincinnati, Ohio. EPA/
600/8-78/017. Available from: National Technical Information Service, 
5285 Port Royal Road, Springfield, Virginia 22161, Publ. No. PB-290329/
AS. Cost: $36.95. Table IA, Note 3.
    (3) ``Methods for Chemical Analysis of Water and Wastes,'' U.S. 
Environmental Protection Agency, EPA-600/4-79-020, March 1979, or 
``Methods for Chemical Analysis of Water and Wastes,'' U.S. 
Environmental Protection Agency, EPA-600/4-79-020, Revised March 1983. 
Available from: ORD Publications, CERI, U.S. Environmental

[[Page 24]]

Protection Agency, Cincinnati, Ohio 45268, Table IB, Note 1.
    (4) ``Methods for Benzidine, Chlorinated Organic Compounds, 
Pentachlorophenol and Pesticides in Water and Wastewater,'' U.S. 
Environmental Protection Agency, 1978. Available from: ORD Publications, 
CERI, U.S. Environmental Protection Agency, Cincinnati, Ohio 45268, 
Table IC, Note 3; Table D, Note 3.
    (5) ``Prescribed Procedures for Measurement of Radioactivity in 
Drinking Water,'' U.S. Environmental Protection Agency, EPA-600/4-80-
032, 1980. Available from: ORD Publications, CERI, U.S. Environmental 
Protection Agency, Cincinnati, Ohio 45268, Table IE, Note 1.
    (6) American Public Health Association. 1992. Standard Methods for 
the Examination of Water and Wastewater. 18th Edition. Amer. Publ. Hlth. 
Assoc., 1015 15th Street NW, Washington, DC 20005. Cost: $160.00. Table 
IA, Note 4.
    (7) Ibid, 15th Edition, 1980. Table IB, Note 30; Table ID.
    (8) Ibid, 14th Edition, 1975. Table IB, Notes 17 and 27.
    (9) ``Selected Analytical Methods Approved and Cited by the United 
States Environmental Protection Agency,'' Supplement to the 15th Edition 
of Standard Methods for the Examination of Water and Wastewater, 1981. 
Available from: American Public Health Association, 1015 Fifteenth 
Street NW., Washington, DC 20036. Cost available from publisher. Table 
IB, Note 10; Table IC, Note 6; Table ID, Note 6.
    (10) Annual Book of ASTM Standards, Water and Environmental 
Technology, Section 11, Volumes 11.01 and 11.02, 1994 in 40 CFR 136.3, 
Tables IB, IC, ID and IE.
    (11) USGS. 1989. U.S. Geological Survey Techniques of Water-
Resources Investigations, Book 5, Laboratory Analysis, Chapter A4, 
Methods for Collection and Analysis of Aquatic Biological and 
Microbiological Samples, U.S. Geological Survey, U.S. Department of the 
Interior, Reston, Virginia. Available from: USGS Books and Open-File 
Reports Section, Federal Center, Box 25425, Denver, Colorado 80225. 
Cost: $18.00. Table IA, Note 5.
    (12) ``Methods for Determination of Inorganic Substances in Water 
and Fluvial Sediments,'' by M.J. Fishman and Linda C. Friedman, 
Techniques of Water-Resources Investigations of the U.S. Geological 
Survey, Book 5 Chapter A1 (1989). Available from: U.S. Geological 
Survey, Denver Federal Center, Box 25425, Denver, CO 80225. Cost: 
$108.75 (subject to change). Table IB, Note 2.
    (13) ``Methods for Determination of Inorganic Substances in Water 
and Fluvial Sediments,'' N.W. Skougstad and others, editors. Techniques 
of Water-Resources Investigations of the U.S. Geological Survey, Book 5, 
Chapter A1 (1979). Available from: U.S. Geological Survey, Denver 
Federal Center, Box 25425, Denver, CO 80225. Cost: $10.00 (subject to 
change), Table IB, Note 8.
    (14) ``Methods for the Determination of Organic Substances in Water 
and Fluvial Sediments,'' Wershaw, R.L., et al, Techniques of Water-
Resources Investigations of the U.S. Geological Survey, Book 5, Chapter 
A3 (1987). Available from: U.S. Geological Survey, Denver Federal 
Center, Box 25425, Denver, CO 80225. Cost: $0.90 (subject to change). 
Table IB, Note 24; Table ID, Note 4.
    (15) ``Water Temperature--Influential Factors, Field Measurement and 
Data Presentation,'' by H.H. Stevens, Jr., J. Ficke, and G.F. Smoot, 
Techniques of Water-Resources Investigations of the U.S. Geological 
Survey, Book 1, Chapter D1, 1975. Available from: U.S. Geological 
Survey, Denver Federal Center, Box 25425, Denver, CO 80225. Cost: $1.60 
(subject to change). Table IB, Note 32.
    (16) ``Selected Methods of the U.S. Geological Survey of Analysis of 
Wastewaters,'' by M.J. Fishman and Eugene Brown; U.S. Geological Survey 
Open File Report 76-77 (1976). Available from: U.S. Geological Survey, 
Branch of Distribution, 1200 South Eads Street, Arlington, VA 22202. 
Cost: $13.50 (subject to change). Table IE, Note 2.
    (17) ``Official Methods of Analysis of the Association of Official 
Analytical Chemicals'', Methods manual, 15th Edition (1990). Price: 
$240.00. Available from: The Association of Official Analytical 
Chemists, 2200 Wilson Boulevard, Suite 400, Arlington, VA 22201. Table 
IB, Note 3.
    (18) ``American National Standard on Photographic Processing 
Effluents,'' April 2, 1975. Available from: American

[[Page 25]]

National Standards Institute, 1430 Broadway, New York, New York 10018. 
Table IB, Note 9.
    (19) ``An Investigation of Improved Procedures for Measurement of 
Mill Effluent and Receiving Water Color,'' NCASI Technical Bulletin No. 
253, December 1971. Available from: National Council of the Paper 
Industry for Air and Stream Improvements, Inc., 260 Madison Avenue, New 
York, NY 10016. Cost available from publisher. Table IB, Note 18.
    (20) Ammonia, Automated Electrode Method, Industrial Method Number 
379-75WE, dated February 19, 1976. Technicon Auto Analyzer II. Method 
and price available from Technicon Industrial Systems, Tarrytown, New 
York 10591. Table IB, Note 7.
    (21) Chemical Oxygen Demand, Method 8000, Hach Handbook of Water 
Analysis, 1979. Method price available from Hach Chemical Company, P.O. 
Box 389, Loveland, Colorado 80537. Table IB, Note 14.
    (22) OIC Chemical Oxygen Demand Method, 1978. Method and price 
available from Oceanography International Corporation, 512 West Loop, 
P.O. Box 2980, College Station, Texas 77840. Table IB, Note 13.
    (23) ORION Research Instruction Manual, Residual Chlorine Electrode 
Model 97-70, 1977. Method and price available from ORION Research 
Incorporation, 840 Memorial Drive, Cambridge, Massachusetts 02138. Table 
IB, Note 16.
    (24) Bicinchoninate Method for Copper. Method 8506, Hach Handbook of 
Water Analysis, 1979, Method and price available from Hach Chemical 
Company, P.O. Box 300, Loveland, Colorado 80537. Table IB, Note 19.
    (25) Hydrogen Ion (pH) Automated Electrode Method, Industrial Method 
Number 378-75WA. October 1976. Bran & Luebbe (Technicon) Auto Analyzer 
II. Method and price available from Bran & Luebbe Analyzing 
Technologies, Inc. Elmsford, N.Y. 10523. Table IB, Note 21.
    (26) 1,10-Phenanthroline Method using FerroVer Iron Reagent for 
Water, Hach Method 8008, 1980. Method and price available from Hach 
Chemical Company, P.O. Box 389 Loveland, Colorado 80537. Table IB, Note 
22.
    (27) Periodate Oxidation Method for Manganese, Method 8034, Hach 
Handbook for Water Analysis, 1979. Method and price available from Hach 
Chemical Company, P.O. Box 389, Loveland, Colorado 80537. Table IB, Note 
23.
    (28) Nitrogen, Nitrite--Low Range, Diazotization Method for Water 
and Wastewater, Hach Method 8507, 1979. Method and price available from 
Hach Chemical Company, P.O. Box 389, Loveland, Colorado 80537. Table IB, 
Note 25.
    (29) Zincon Method for Zinc, Method 8009. Hach Handbook for Water 
Analysis, 1979. Method and price available from Hach Chemical Company, 
P.O. Box 389, Loveland, Colorado 80537. Table IB, Note 33.
    (30) ``Direct Determination of Elemental Phosphorus by Gas-Liquid 
Chromatography,'' by R.F. Addison and R.G. Ackman, Journal of 
Chromatography, Volume 47, No. 3, pp. 421-426, 1970. Available in most 
public libraries. Back volumes of the Journal of Chromatography are 
available from Elsevier/North-Holland, Inc., Journal Information Centre, 
52 Vanderbilt Avenue, New York, NY 10164. Cost available from publisher. 
Table IB, Note 28.
    (31) ``Direct Current Plasma (DCP) Optical Emission Spectrometric 
Method for Trace Elemental Analysis of Water and Wastes'', Method AES 
0029, 1986-Revised 1991, Fison Instruments, Inc., 32 Commerce Center, 
Cherry Hill Drive, Danvers, MA 01923. Table B, Note 34.
    (32) ``Closed Vessel Microwave Digestion of Wastewater Samples for 
Determination of Metals, CEM Corporation, P.O. Box 200, Matthews, North 
Carolina 28106-0200, April 16, 1992. Available from the CEM Corporation. 
Table IB, Note 36.
    (33) ``Organochlorine Pesticides and PCBs in Wastewater Using Empore 
TM Disk'' Test Method 3M 0222, Revised 10/28/94. 3M 
Corporation, 3M Center Building 220-9E-10, St. Paul, MN 55144-1000. 
Method available from 3M Corporation. Table IC, Note 8 and Table ID, 
Note 8.
    (34) USEPA. 1993. Methods for Measuring the Acute Toxicity of 
Effluents to Freshwater and Marine Organisms.

[[Page 26]]

Fourth Edition, December 1993. Environmental Monitoring Systems 
Laboratory, U.S. Environmental Protection Agency, Cincinnati, Ohio (EPA/
600/4-90/027F). Available from: National Technical Information Service, 
5285 Port Royal Road, Springfield, Virginia 22161, Publ. No. PB-91-
167650. Cost: $31.00. Table IA, Note 17. See changes in the manual, 
listed in Part V of this rule.
    (35) ``Nitrogen, Total Kjeldahl, Method PAI-DK01 (Block Digestion, 
Steam Distillation, Titrimetric Detection)'', revised 12/22/94. 
Available from Perstorp Analytical Corporation, 9445 SW Ridder Rd., 
Suite 310, P.O. Box 648, Wilsonville, OK 97070. Table IB, Note 39.
    (36) ``Nitrogen, Total Kjeldahl, Method PAI-DK02 (Block Digestion, 
Steam Distillation, Colorimetric Detection)'', revised 12/22/94. 
Available from Perstorp Analytical Corporation, 9445 SW Ridder Rd., 
Suite 310, P.O. Box 648, Wilsonville, OK 97070. Table IB, Note 40.
    (37) ``Nitrogen, Total Kjeldahl, Method PAI-DK03 (Block Digestion, 
Automated FIA Gas Diffusion)'', revised 12/22/94. Available from 
Perstorp Analytical Corporation, 9445 SW Ridder Rd., Suite 310, P.O. Box 
648, Wilsonville, OK 97070. Table IB, Note 41.
    (38) USEPA. 1994. Short-term Methods for Estimating the Chronic 
Toxicity of Effluents and Receiving Waters to Freshwater Organisms. 
Third Edition. July 1994. Environmental Monitoring Systems Laboratory, 
U.S. Environmental Protection Agency, Cincinnati, Ohio. (EPA/600/4-91/
002). Available from: National Technical Information Service, 5285 Port 
Royal Road, Springfield, Virginia 22161, Publ. No. PB-92-139492. Cost: 
$31.00. Table IA, Note 8.
    (39) USEPA. 1994. Short-term Methods for Estimating the Chronic 
Toxicity of Effluents and Receiving Waters to Marine and Estuarine 
Organisms. Second Edition, July 1994. Environmental Monitoring Systems 
Laboratory, U.S. Environmental Protection Agency, Cincinnati, Ohio. EPA/
600/4-91/003. Available from: National Technical Information Service, 
5285 Port Royal Road, Springfield, Virginia 22161, Publ. No. PB-92-
139484. Cost: $45.00. Table IA, Note 9.
    (40) EPA Methods 1666, 1667, and 1671 listed in the table above are 
published in the compendium titled Analytical Methods for the 
Determination of Pollutants in Pharmaceutical Manufacturing Industry 
Wastewaters (EPA 821-B-98-016). EPA Methods 502.2 and 524.2 have been 
incorporated by reference into 40 CFR 141.24 and are in Methods for the 
Determination of Organic Compounds in Drinking Water, EPA-600/4-88-039, 
December 1988, Revised, July 1991, and Methods for the Determination of 
Organic Compounds in Drinking Water-Supplement II, EPA-600/R-92-129, 
August 1992, respectively. These EPA test method compendia are available 
from the National Technical Information Service, NTIS PB91-231480 and 
PB92-207703, U.S. Department of Commerce, 5285 Port Royal Road, 
Springfield, Virginia 22161. The toll-free number is 800-553-6847. ASTM 
test methods D3371, D3695, and D4763 are available from the American 
Society for Testing and Materials, 100 Barr Harbor Drive, West 
Conshohocken, PA 19428-2959.
    (41) USEPA. 2001. Method 1631, Revision C, ``Mercury in Water by 
Oxidation, Purge and Trap, and Cold Vapor Atomic Fluorescence 
Spectrometry.'' March 2001. Office of Water, U.S. Environmental 
Protection Agency (EPA-821-R-01-024). Available from: National Technical 
Information Service, 5285 Port Royal Road, Springfield, Virginia 22161. 
Publication No. PB2001-102796. Cost: $25.50. Table IB, Note 43.
    (42) USEPA, January 1999 Errata for the Effluent and Receiving Water 
Testing Manuals: Acute Toxicity of Effluents and Receiving Waters to 
Freshwater and Marine Organisms; Short-Term Methods for Estimating the 
Chronic Toxicity of Effluents and Receiving Waters to Freshwater 
Organisms; and Short-Term Methods for Estimating the Chronic Toxicity of 
Effluents and Receiving Waters to Marine and Estuarine Organisms. U.S. 
Environmental Protection Agency, Office of Research and Development, 
Duluth, MN. EPA-600/R-98/182.
    (43) Method OIA-1677, Available Cyanide by Flow Injection, Ligand 
Exchange, and Amperometry. August 1999. ALPKEM, OI Analytical, Box 648,

[[Page 27]]

Wilsonville, Oregon 97070 (EPA-821-R-99-013). Available from: National 
Technical Information Service, 5285 Port Royal Road, Springfield, 
Virginia 22161. Publication No. PB99-132011. Cost: $22.50. Table IB, 
Note 44.
    (c) Under certain circumstances the Regional Administrator or the 
Director in the Region or State where the discharge will occur may 
determine for a particular discharge that additional parameters or 
pollutants must be reported. Under such circumstances, additional test 
procedures for analysis of pollutants may be specified by the Regional 
Administrator, or the Director upon the recommendation of the Director 
of the Environmental Monitoring Systems Laboratory--Cincinnati.
    (d) Under certain circumstances, the Administrator may approve, upon 
recommendation by the Director, Environmental Monitoring Systems 
Laboratory--Cincinnati, additional alternate test procedures for 
nationwide use.
    (e) Sample preservation procedures, container materials, and maximum 
allowable holding times for parameters cited in Tables IA, IB, IC, ID, 
and IE are prescribed in Table II. Any person may apply for a variance 
from the prescribed preservation techniques, container materials, and 
maximum holding times applicable to samples taken from a specific 
discharge. Applications for variances may be made by letters to the 
Regional Administrator in the Region in which the discharge will occur. 
Sufficient data should be provided to assure such variance does not 
adversely affect the integrity of the sample. Such data will be 
forwarded, by the Regional Administrator, to the Director of the 
Environmental Monitoring Systems Laboratory--Cincinnati, Ohio for 
technical review and recommendations for action on the variance 
application. Upon receipt of the recommendations from the Director of 
the Environmental Monitoring Systems Laboratory, the Regional 
Administrator may grant a variance applicable to the specific charge to 
the applicant. A decision to approve or deny a variance will be made 
within 90 days of receipt of the application by the Regional 
Administrator.

                    Table II--Required Containers, Preservation Techniques, and Holding Times
----------------------------------------------------------------------------------------------------------------
       Parameter No./name           Container \1\          Preservation \2,\ \3\        Maximum holding time \4\
----------------------------------------------------------------------------------------------------------------
Table IA--Bacteria Tests:
  1-4 Coliform, fecal and total.  P,G..............  Cool, 4C, 0.008% Na2S2O3 5......  6 hours.
  5 Fecal streptococci..........  P,G..............  Cool, 4C, 0.008% Na2S2O3 5......  6 hours.
Table IA--Aquatic Toxicity
 Tests:
  6-10 Toxicity, acute and        P,G..............  Cool, 4  deg.C 16...............  36 hours.
   chronic.
 
Table IB--Inorganic Tests:
  1. Acidity....................  P, G.............  Cool, 4 deg.C...................  14 days.
  2. Alkalinity.................  P, G.............  ......do........................      Do.
  4. Ammonia....................  P, G.............  Cool, 4 deg.C, H2SO4 to pH<2....  28 days.
  9. Biochemical oxygen demand..  P, G.............  Cool, 4 deg.C...................  48 hours.
  10. Boron.....................  P, PFTE, or        HNO3 TO pH<2....................  6 months.
                                   Quartz.
  11. Bromide...................  P, G.............  None required...................  28 days.
  14. Biochemical oxygen demand,  P, G.............  Cool, 4 deg.C...................  48 hours.
   carbonaceous.
  15. Chemical oxygen demand....  P, G.............  Cool, 4 deg.C, H2SO4 to pH<2....  28 days.
  16. Chloride..................  P, G.............  None required...................      Do.
  17. Chlorine, total residual..  P, G.............  ......do........................  Analyze immediately.
  21. Color.....................  P, G.............  Cool, 4 deg.C...................  48 hours.
  23-24. Cyanide, total and       P, G.............  Cool, 4 deg.C, NaOH to pH6
   amenable to chlorination.                          eq>12, 0.6g ascorbic acid 5.
  25. Fluoride..................  P................  None required...................  28 days.
  27. Hardness..................  P, G.............  HNO3 to pH<2, H2SO4 to pH<2.....  6 months.
  28. Hydrogen ion (pH).........  P, G.............  None required...................  Analyze immediately.
  31, 43. Kjeldahl and organic    P, G.............  Cool, 4 deg.C, H2SO4 to pH<2....  28 days.
   nitrogen.
Metals:7
  18. Chromium VI...............  P, G.............  Cool, 4 deg.C...................  24 hours.
  35. Mercury...................  P, G.............  HNO3 to pH<2....................  28 days.
  3, 5-8, 12, 13, 19, 20, 22,     P, G.............  ......do........................  6 months.
   26, 29, 30, 32-34, 36, 37,
   45, 47, 51, 52, 58-60, 62,
   63, 70-72, 74, 75. Metals,
   except boron, chromium VI and
   mercury.
  38. Nitrate...................  P, G.............  Cool, 4 deg.C...................  48 hours.
  39. Nitrate-nitrite...........  P, G.............  Cool, 4 deg.C, H2SO4 to pH<2....  28 days.

[[Page 28]]

 
  40. Nitrite...................  P, G.............  Cool, 4 deg.C...................  48 hours.
  41. Oil and grease............  G................  Cool to 4 deg.C, HCl or H2SO4 to  28 days.
                                                      pH<2.
  42. Organic Carbon............  P, G.............  Cool to 4  deg.C HC1 or H2SO4 or  28 days.
                                                      H3PO4, to pH<2.
  44. Orthophosphate............  P, G.............  Filter immediately, Cool, 4       48 hours.
                                                      deg.C.
  46. Oxygen, Dissolved Probe...  G Bottle and top.  None required...................  Analyze immediately.
  47. Winkler...................  ......do.........  Fix on site and store in dark...  8 hours.
  48. Phenols...................  G only...........  Cool, 4 deg.C, H2SO4 to pH<2....  28 days.
  49. Phosphorus (elemental)....  G................  Cool, 4 deg.C...................  48 hours.
  50. Phosphorus, total.........  P, G.............  Cool, 4 deg.C, H2SO4 to pH<2....  28 days.
  53. Residue, total............  P, G.............  Cool, 4 deg.C...................  7 days.
  54. Residue, Filterable.......  P, G.............  ......do........................  7 days.
  55. Residue, Nonfilterable      P, G.............  ......do........................  7 days.
   (TSS).
  56. Residue, Settleable.......  P, G.............  ......do........................  48 hours.
  57. Residue, volatile.........  P, G.............  ......do........................  7 days.
  61. Silica....................  P, PFTE, or        Cool, 4  deg.C..................  28 days.
                                   Quartz.
  64. Specific conductance......  P, G.............  ......do........................      Do.
  65. Sulfate...................  P, G.............  ......do........................      Do.
  66. Sulfide...................  P, G.............  Cool, 4 deg.C add zinc acetate    7 days.
                                                      plus sodium hydroxide to pH9.
  67. Sulfite...................  P, G.............  None required...................  Analyze immediately.
  68. Surfactants...............  P ,G.............  Cool, 4 deg.C...................  48 hours.
  69. Temperature...............  P, G.............  None required...................  Analyze.
  73. Turbidity.................  P, G.............  Cool, 4 deg.C...................  48 hours.
Table IC--Organic Tests \8\
  13, 18-20, 22, 24-28, 34-37,    G, Teflon-lined    Cool, 4  deg.C, 0.008% Na2S2O3    14 days.
   39-43, 45-47, 56, 76, 104,      septum.            \5\..
   105, 108-111, 113. Purgeable
   Halocarbons.
  6, 57, 106. Purgeable aromatic  ......do.........  Cool, 4  deg.C, 0.008%                Do.
   hydrocarbons.                                      Na2S2O3,\5\ HCl to pH2\9\.
  3, 4. Acrolein and              ......do.........  Cool, 4  deg.C, 0.008%                Do.
   acrylonitrile.                                     Na2S2O3,\5\ adjust pH to 4-510.
  23, 30, 44, 49, 53, 77, 80,     G, Teflon-lined    Cool, 4  deg.C, 0.008% Na2S2O3    7 days until extraction;
   81, 98, 100, 112. Phenols 11.   cap..              \5\.                              40 days after
                                                                                        extraction.
  7, 38. Benzidines 11..........  ......do.........  ......do........................  7 days until
                                                                                        extraction.13
  14, 17, 48, 50-52. Phthalate    ......do.........  Cool, 4  deg.C..................  7 days until extraction;
   esters 11.                                                                           40 days after
                                                                                        extraction.
  82-84. Nitrosamines 11 14.....  ......do.........  Cool, 4  deg.C, 0.008%                Do.
                                                      Na2S2O3,\5\ store in dark.
  88-94. PCBs 11................  .....do..........  Cool, 4  deg.C..................      Do.
  54, 55, 75, 79. Nitroaromatics  ......do.........  Cool, 4  deg.C, 0.008%                Do.
   and isophorone 11.                                 Na2S2O3,\5\ store in dark.
  1, 2, 5, 8-12, 32, 33, 58, 59,  ......do.........  ......do........................      Do.
   74, 78, 99, 101. Polynuclear
   aromatic hydrocarbons 11.
  15, 16, 21, 31, 87. Haloethers  ......do.........  Cool, 4  deg.C, 0.008% Na2S2O3        Do.
   11.                                                \5\.
  29, 35-37, 63-65, 73, 107.      ......do.........  Cool, 4  deg.C..................      Do.
   Chlorinated hydrocarbons 11.
  60-62, 66-72, 85, 86, 95-97,
   102, 103. CDDs/CDFs 11.
  aqueous: field and lab          G................  Cool, 0-4  deg.C, pH<9, 0.008%    1 year.
   preservation..                                     Na2S2O3 \5\.
  Solids, mixed phase, and        ......do.........  Cool, <4  deg.C.................  7 days.
   tissue: field preservation..
  Solids, mixed phase, and        ......do.........  Freeze, <-10  deg.C.............  1 year.
   tissue: lab preservation.
Table ID--Pesticides Tests:
  1-70. Pesticides \11\.........  ......do.........  Cool, 4 deg.C, pH 5-9 15........      Do.
Table IE--Radiological Tests:
  1-5. Alpha, beta and radium...  P, G.............  HNO3 to pH<2....................  6 months.
----------------------------------------------------------------------------------------------------------------
Table II Notes
\1\ Polyethylene (P) or glass (G). For microbiology, plastic sample containers must be made of sterilizable
  materials (polypropylene or other autoclavable plastic).
2 Sample preservation should be performed immediately upon sample collection. For composite chemical samples
  each aliquot should be preserved at the time of collection. When use of an automated sampler makes it
  impossible to preserve each aliquot, then chemical samples may be preserved by maintaining at 4 deg.C until
  compositing and sample splitting is completed.

[[Page 29]]

 
3 When any sample is to be shipped by common carrier or sent through the United States Mails, it must comply
  with the Department of Transportation Hazardous Materials Regulations (49 CFR part 172). The person offering
  such material for transportation is responsible for ensuring such compliance. For the preservation
  requirements of Table II, the Office of Hazardous Materials, Materials Transportation Bureau, Department of
  Transportation has determined that the Hazardous Materials Regulations do not apply to the following
  materials: Hydrochloric acid (HCl) in water solutions at concentrations of 0.04% by weight or less (pH about
  1.96 or greater); Nitric acid (HNO3) in water solutions at concentrations of 0.15% by weight or less (pH about
  1.62 or greater); Sulfuric acid (H2SO4) in water solutions at concentrations of 0.35% by weight or less (pH
  about 1.15 or greater); and Sodium hydroxide (NaOH) in water solutions at concentrations of 0.080% by weight
  or less (pH about 12.30 or less).
\4\ Samples should be analyzed as soon as possible after collection. The times listed are the maximum times that
  samples may be held before analysis and still be considered valid. Samples may be held for longer periods only
  if the permittee, or monitoring laboratory, has data on file to show that for the specific types of samples
  under study, the analytes are stable for the longer time, and has received a variance from the Regional
  Administrator under Sec.  136.3(e). Some samples may not be stable for the maximum time period given in the
  table. A permittee, or monitoring laboratory, is obligated to hold the sample for a shorter time if knowledge
  exists to show that this is necessary to maintain sample stability. See Sec.  136.3(e) for details. The term
  ``analyze immediately'' usually means within 15 minutes or less of sample collection.
5 Should only be used in the presence of residual chlorine.
6 Maximum holding time is 24 hours when sulfide is present. Optionally all samples may be tested with lead
  acetate paper before pH adjustments in order to determine if sulfide is present. If sulfide is present, it can
  be removed by the addition of cadmium nitrate powder until a negative spot test is obtained. The sample is
  filtered and then NaOH is added to pH 12.
7 Samples should be filtered immediately on-site before adding preservative for dissolved metals.
8 Guidance applies to samples to be analyzed by GC, LC, or GC/MS for specific compounds.
9 Sample receiving no pH adjustment must be analyzed within seven days of sampling.
10 The pH adjustment is not required if acrolein will not be measured. Samples for acrolein receiving no pH
  adjustment must be analyzed within 3 days of sampling.
11 When the extractable analytes of concern fall within a single chemical category, the specified preservative
  and maximum holding times should be observed for optimum safeguard of sample integrity. When the analytes of
  concern fall within two or more chemical categories, the sample may be preserved by cooling to 4 deg.C,
  reducing residual chlorine with 0.008% sodium thiosulfate, storing in the dark, and adjusting the pH to 6-9;
  samples preserved in this manner may be held for seven days before extraction and for forty days after
  extraction. Exceptions to this optional preservation and holding time procedure are noted in footnote 5 (re
  the requirement for thiosulfate reduction of residual chlorine), and footnotes 12, 13 (re the analysis of
  benzidine).
12 If 1,2-diphenylhydrazine is likely to be present, adjust the pH of the sample to 4.00.2 to
  prevent rearrangement to benzidine.
13 Extracts may be stored up to 7 days before analysis if storage is conducted under an inert (oxidant-free)
  atmosphere.
14 For the analysis of diphenylnitrosamine, add 0.008% Na2S2O3 and adjust pH to 7-10 with NaOH within 24 hours
  of sampling.
15 The pH adjustment may be performed upon receipt at the laboratory and may be omitted if the samples are
  extracted within 72 hours of collection. For the analysis of aldrin, add 0.008% Na2S2O3.
\16\ Sufficient ice should be placed with the samples in the shipping container to ensure that ice is still
  present when the samples arrive at the laboratory. However, even if ice is present when the samples arrive, it
  is necessary to immediately measure the temperature of the samples and confirm that the 4C temperature maximum
  has not been exceeded. In the isolated cases where it can be documented that this holding temperature can not
  be met, the permittee can be given the option of on-site testing or can request a variance. The request for a
  variance should include supportive data which show that the toxicity of the effluent samples is not reduced
  because of the increased holding temperature.

[38 FR 28758, Oct. 16, 1973, as amended at 41 FR 52781, Dec. 1, 1976; 49 
FR 43251, 43258, 43259, Oct. 26, 1984; 50 FR 691, 692, 695, Jan. 4, 
1985; 51 FR 23693, June 30, 1986; 52 FR 33543, Sept. 3, 1987; 55 FR 
24534, June 15, 1990; 55 FR 33440, Aug. 15, 1990; 56 FR 50759, Oct. 8, 
1991; 57 FR 41833, Sept. 11, 1992; 58 FR 4505, Jan. 31, 1994; 60 FR 
17160, Apr. 4, 1995; 60 FR 39588, 39590, Aug. 2, 1995; 60 FR 44672, Aug. 
28, 1995; 60 FR 53542, 53543, Oct. 16, 1995; 62 FR 48403, 48404, Sept. 
15, 1997; 63 FR 50423, Sept. 21, 1998; 64 FR 4978, Feb. 2, 1999; 64 FR 
10392, Mar. 4, 1999; 64 FR 26327, May 14, 1999; 64 FR 30433, 30434, June 
8, 1999; 64 FR 73423, Dec. 30, 1999; 66 FR 32776, June 18, 2001]



Sec. 136.4  Application for alternate test procedures.

    (a) Any person may apply to the Regional Administrator in the Region 
where the discharge occurs for approval of an alternative test 
procedure.
    (b) When the discharge for which an alternative test procedure is 
proposed occurs within a State having a permit program approved pursuant 
to section 402 of the Act, the applicant shall submit his application to 
the Regional Administrator through the Director of the State agency 
having responsibility for issuance of NPDES permits within such State.
    (c) Unless and until printed application forms are made available, 
an application for an alternate test procedure may be made by letter in 
triplicate. Any application for an alternate test procedure under this 
paragraph (c) shall:
    (1) Provide the name and address of the responsible person or firm 
making the discharge (if not the applicant) and the applicable ID number 
of the existing or pending permit, issuing agency, and type of permit 
for which the alternate test procedure is requested, and the discharge 
serial number.
    (2) Identify the pollutant or parameter for which approval of an 
alternate testing procedure is being requested.
    (3) Provide justification for using testing procedures other than 
those specified in Table I.
    (4) Provide a detailed description of the proposed alternate test 
procedure, together with references to published

[[Page 30]]

studies of the applicability of the alternate test procedure to the 
effluents in question.
    (d) An application for approval of an alternate test procedure for 
nationwide use may be made by letter in triplicate to the Director, 
Analytical Methods Staff, Office of Science and Technology (4303), 
Office of Water, U.S. Environmental Protection Agency, 1200 Pennsylvania 
Ave., NW., Washington, DC 20460. Any application for an alternate test 
procedure under this paragraph (d) shall:
    (1) Provide the name and address of the responsible person or firm 
making the application.
    (2) Identify the pollutant(s) or parameter(s) for which nationwide 
approval of an alternate testing procedure is being requested.
    (3) Provide a detailed description of the proposed alternate 
procedure, together with references to published or other studies 
confirming the general applicability of the alternate test procedure to 
the pollutant(s) or parameter(s) in waste water discharges from 
representative and specified industrial or other categories.
    (4) Provide comparability data for the performance of the proposed 
alternate test procedure compared to the performance of the approved 
test procedures.

[38 FR 28760, Oct. 16, 1973, as amended at 41 FR 52785, Dec. 1, 1976; 62 
FR 30763, June 5, 1997]



Sec. 136.5  Approval of alternate test procedures.

    (a) The Regional Administrator of the region in which the discharge 
will occur has final responsibility for approval of any alternate test 
procedure proposed by the responsible person or firm making the 
discharge.
    (b) Within thirty days of receipt of an application, the Director 
will forward such application proposed by the responsible person or firm 
making the discharge, together with his recommendations, to the Regional 
Administrator. Where the Director recommends rejection of the 
application for scientific and technical reasons which he provides, the 
Regional Administrator shall deny the application, and shall forward a 
copy of the rejected application and his decision to the Director of the 
State Permit Program and to the Director of the Analytical Methods 
Staff, Washington, DC.
    (c) Before approving any application for an alternate test procedure 
proposed by the responsible person or firm making the discharge, the 
Regional Administrator shall forward a copy of the application to the 
Director of the Analytical Methods Staff, Washington, DC.
    (d) Within ninety days of receipt by the Regional Administrator of 
an application for an alternate test procedure, proposed by the 
responsible person or firm making the discharge, the Regional 
Administrator shall notify the applicant and the appropriate State 
agency of approval or rejection, or shall specify the additional 
information which is required to determine whether to approve the 
proposed test procedure. Prior to the expiration of such ninety day 
period, a recommendation providing the scientific and other technical 
basis for acceptance or rejection will be forwarded to the Regional 
Administrator by the Director of the Analytical Methods Staff, 
Washington, DC. A copy of all approval and rejection notifications will 
be forwarded to the Director, Analytical Methods Staff, Washington, DC, 
for the purposes of national coordination.
    (e) Approval for nationwide use. (1) Within sixty days of the 
receipt by the Director of the Analytical Methods Staff, Washington, DC, 
of an application for an alternate test procedure for nationwide use, 
the Director of the Analytical Methods Staff shall notify the applicant 
in writing whether the application is complete. If the application is 
incomplete, the applicant shall be informed of the information necessary 
to make the application complete.
    (2) Within ninety days of the receipt of a complete package, the 
Analytical Methods Staff shall perform any analysis necessary to 
determine whether the alternate method satisfies the applicable 
requirements of this part, and the Director of the Analytical Methods 
Staff shall recommend to the Administrator that he/she approve or reject 
the application and shall also notify the applicant of such 
recommendation.

[[Page 31]]

    (3) As expeditiously as practicable, an alternate method determined 
by the Administrator to satisfy the applicable requirements of this part 
shall be proposed by EPA for incorporation in subsection 136.3 of 40 CFR 
part 136. EPA shall make available for review all the factual bases for 
its proposal, including any performance data submitted by the applicant 
and any available EPA analysis of those data.
    (4) Following a period of public comment, EPA shall, as 
expeditiously as practicable, publish in the Federal Register a final 
decision to approve or reject the alternate method.

[38 FR 28760, Oct. 16, 1973, as amended at 41 FR 52785, Dec. 1, 1976; 55 
FR 33440, Aug. 15, 1990; 62 FR 30763, June 5, 1997]

    Appendix A to Part 136--Methods for Organic Chemical Analysis of 
                   Municipal and Industrial Wastewater

                    Method 601--Purgeable Halocarbons

                        1. Scope and Application

    1.1  This method covers the determination of 29 purgeable 
halocarbons.
    The following parameters may be determined by this method:

------------------------------------------------------------------------
                                                  STORET
                   Parameter                       No.        CAS No.
------------------------------------------------------------------------
Bromodichloromethane...........................    32101         75-27-4
Bromoform......................................    32104         75-25-2
Bromomethane...................................    34413         74-83-9
Carbon tetrachloride...........................    32102         56-23-5
Chlorobenzene..................................    34301        108-90-7
Chloroethane...................................    34311         75-00-3
2-Chloroethylvinyl ether.......................    34576        100-75-8
Chloroform.....................................    32106         67-66-3
Chloromethane..................................    34418         74-87-3
Dibromochloromethane...........................    32105        124-48-1
1,2-Dichlorobenzene............................    34536         95-50-1
1,3-Dichlorobenzene............................    34566        541-73-1
1,4-Dichlorobenzene............................    34571        106-46-7
Dichlorodifluoromethane........................    34668         75-71-8
1,1-Dichloroethane.............................    34496         75-34-3
1,2-Dichloroethane.............................    34531        107-06-2
1,1-Dichloroethane.............................    34501         75-35-4
trans-1,2-Dichloroethene.......................    34546        156-60-5
1,2-Dichloropropane............................    34541         78-87-5
cis-1,3-Dichloropropene........................    34704      10061-01-5
trans-1,3-Dichloropropene......................    34699      10061-02-6
Methylene chloride.............................    34423         75-09-2
1,1,2,2-Tetrachloroethane......................    34516         79-34-5
Tetrachloroethene..............................    34475        127-18-4
1,1,1-Trichloroethane..........................    34506         71-55-6
1,1,2-Trichloroethane..........................    34511         79-00-5
Tetrachloroethene..............................    39180         79-01-6
Trichlorofluoromethane.........................    34488         75-69-4
Vinyl chloride.................................    39715         75-01-4
------------------------------------------------------------------------

    1.2  This is a purge and trap gas chromatographic (GC) method 
applicable to the determination of the compounds listed above in 
municipal and industrial discharges as provided under 40 CFR 136.1. When 
this method is used to analyze unfamiliar samples for any or all of the 
compounds above, compound identifications should be supported by at 
least one additional qualitative technique. This method describes 
analytical conditions for a second gas chromatographic column that can 
be used to confirm measurements made with the primary column. Method 624 
provides gas chromatograph/mass spectrometer (GC/MS) conditions 
appropriate for the qualitative and quantitative confirmation of results 
for most of the parameters listed above.
    1.3  The method detection limit (MDL, defined in Section 12.1) 
1 for each parameter is listed in Table 1. The MDL for a 
specific wastewater may differ from those listed, depending upon the 
nature of interferences in the sample matrix.
    1.4  Any modification of this method, beyond those expressly 
permitted, shall be considered as a major modification subject to 
application and approval of alternate test procedures under 40 CFR 136.4 
and 136.5.
    1.5  This method is restricted to use by or under the supervision of 
analysts experienced in the operation of a purge and trap system and a 
gas chromatograph and in the interpretation of gas chromatograms. Each 
analyst must demonstrate the ability to generate acceptable results with 
this method using the procedure described in Section 8.2.

                          2. Summary of Method

    2.1  An inert gas is bubbled through a 5-mL water sample contained 
in a specially-designed purging chamber at ambient temperature. The 
halocarbons are efficiently transferred from the aqueous phase to the 
vapor phase. The vapor is swept through a sorbent trap where the 
halocarbons are trapped. After purging is completed, the trap is heated 
and backflushed with the inert gas to desorb the halocarbons onto a gas 
chromatographic column. The gas chromatograph is temperature programmed 
to separate the halocarbons which are then detected with a halide-
specific detector.2,3
    2.2  The method provides an optional gas chromatographic column that 
may be helpful in resolving the compounds of interest from interferences 
that may occur.

                            3. Interferences

    3.1  Impurities in the purge gas and organic compounds outgassing 
from the plumbing ahead of the trap account for the majority of 
contamination problems. The analytical system must be demonstrated to be 
free from contamination under the conditions of the analysis by running 
laboratory reagent blanks as described in Section 8.1.3. The use of non-
Teflon plastic tubing, non-Teflon

[[Page 32]]

thread sealants, or flow controllers with rubber components in the purge 
and trap system should be avoided.
    3.2  Samples can be contaminated by diffusion of volatile organics 
(particularly fluorocarbons and methylene chloride) through the septum 
seal ilto the sample during shipment and storage. A field reagent blank 
prepared from reagent water and carried through the sampling and 
handling protocol can serve as a check on such contamination.
    3.3  Contamination by carry-over can occur whenever high level and 
low level samples are sequentially analyzed. To reduce carry-over, the 
purging device and sample syringe must be rinsed with reagent water 
between sample analyses. Whenever an unusually concentrated sample is 
encountered, it should be followed by an analysis of reagent water to 
check for cross contamination. For samples containing large amounts of 
water-soluble materials, suspended solids, high boiling compounds or 
high organohalide levels, it may be necessary to wash out the purging 
device with a detergent solution, rinse it with distilled water, and 
then dry it in a 105 deg.C oven between analyses. The trap and other 
parts of the system are also subject to contamination; therefore, 
frequent bakeout and purging of the entire system may be required.

                                4. Safety

    4.1  The toxicity or carcinogenicity of each reagent used in this 
method has not been precisely defined; however, each chemical compound 
should be treated as a potential health hazard. From this viewpoint, 
exposure to these chemicals must be reduced to the lowest possible level 
by whatever means available. The laboratory is responsible for 
maintaining a current awareness file of OSHA regulations regarding the 
safe handling of the chemicals specified in this method. A reference 
file of material data handling sheets should also be made available to 
all personnel involved in the chemical analysis. Additional references 
to laboratory safety are available and have been identified 
4-6 for the information of the analyst.
    4.2  The following parameters covered by this method have been 
tentatively classified as known or suspected, human or mammalian 
carcinogens: carbon tetrachloride, chloroform, 1,4-dichlorobenzene, and 
vinyl chloride. Primary standards of these toxic compounds should be 
prepared in a hood. A NIOSH/MESA approved toxic gas respirator should be 
worn when the analyst handles high concentrations of these toxic 
compounds.

                       5. Apparatus and Materials

    5.1  Sampling equipment, for discrete sampling.
    5.1.1  Vial--25-mL capacity or larger, equipped with a screw cap 
with a hole in the center (Pierce 13075 or equivalent). 
Detergent wash, rinse with tap and distilled water, and dry at 105 
deg.C before use.
    5.1.2  Septum--Teflon-faced silicone (Pierce 12722 or 
equivalent). Detergent wash, rinse with tap and distilled water, and dry 
at 105  deg.C for 1 h before use.
    5.2  Purge and trap system--The purge and trap system consists of 
three separate pieces of equipment: a purging device, trap, and 
desorber. Several complete systems are now commercially available.
    5.2.1  The purging device must be designed to accept 5-mL samples 
with a water column at least 3 cm deep. The gaseous head space between 
the water column and the trap must have a total volume of less than 15 
mL. The purge gas must pass through the water column as finely divided 
bubbles with a diameter of less than 3 mm at the origin. The purge gas 
must be introduced no more than 5 mm from the base of the water column. 
The purging device illustrated in Figure 1 meets these design criteria.
    5.2.2  The trap must be at least 25 cm long and have an inside 
diameter of at least 0.105 in. The trap must be packed to contain the 
following minimum lengths of adsorbents: 1.0 cm of methyl silicone 
coated packing (Section 6.3.3), 7.7 cm of 2,6-diphenylene oxide polymer 
(Section 6.3.2), 7.7 cm of silica gel (Section 6.3.4), 7.7 cm of coconut 
charcoal (Section 6.3.1). If it is not necessary to analyze for 
dichlorodifluoromethane, the charcoal can be eliminated, and the polymer 
section lengthened to 15 cm. The minimum specifications for the trap are 
illustrated in Figure 2.
    5.2.3  The desorber must be capable of rapidly heating the trap to 
180  deg.C. The polymer section of the trap should not be heated higher 
than 180  deg.C and the remaining sections should not exceed 200  deg.C. 
The desorber illustrated in Figure 2 meets these design criteria.
    5.2.4  The purge and trap system may be assembled as a separate unit 
or be coupled to a gas chromatograph as illustrated in Figures 3 and 4.
    5.3  Gas chromatograph--An analytical system complete with a 
temperature programmable gas chromatograph suitable for on-column 
injection and all required accessories including syringes, analytical 
columns, gases, detector, and strip-chart recorder. A data system is 
recommended for measuring peak areas.
    5.3.1  Column 1--8 ft long x 0.1 in. ID stainless steel or glass, 
packed with 1% SP-1000 on Carbopack B (60/80 mesh) or equivalent. This 
column was used to develop the method performance statements in Section 
12. Guidelines for the use of alternate column packings are provided in 
Section 10.1.

[[Page 33]]

    5.3.2  Column 2--6 ft long x 0.1 in. ID stainless steel or glass, 
packed with chemically bonded n-octane on Porasil-C (100/120 mesh) or 
equivalent.
    5.3.3  Detector--Electrolytic conductivity or microcoulometric 
detector. These types of detectors have proven effective in the analysis 
of wastewaters for the parameters listed in the scope (Section 1.1). The 
electrolytic conductivity detector was used to develop the method 
performance statements in Section 12. Guidelines for the use of 
alternate detectors are provided in Section 10.1.
    5.4  Syringes--5-mL glass hypodermic with Luerlok tip (two each), if 
applicable to the purging device.
    5.5  Micro syringes--25-[mu]L, 0.006 in. ID needle.
    5.6  Syringe valve--2-way, with Luer ends (three each).
    5.7  Syringe--5-mL, gas-tight with shut-off valve.
    5.8  Bottle--15-mL, screw-cap, with Teflon cap liner.
    5.9  Balance--Analytical, capable of accurately weighing 0.0001 g.

                               6. Reagents

    6.1  Reagent water--Reagent water is defined as a water in which an 
interferent is not observed at the MDL of the parameters of interest.
    6.1.1  Reagent water can be generated by passing tap water through a 
carbon filter bed containing about 1 lb of activated carbon (Filtrasorb-
300, Calgon Corp., or equivalent).
    6.1.2  A water purification system (Millipore Super-Q or equivalent) 
may be used to generate reagent water.
    6.1.3  Reagent water may also be prepared by boiling water for 15 
min. Subsequently, while maintaining the temperature at 
90 deg.C, bubble a contaminant-free inert gas through the 
water for 1 h. While still hot, transfer the water to a narrow mouth 
screw-cap bottle and seal with a Teflon-lined septum and cap.
    6.2  Sodium thiosulfate--(ACS) Granular.
    6.3  Trap Materials:
    6.3.1  Coconut charcoal--6/10 mesh sieved to 26 mesh, Barnabey 
Cheney, CA-580-26 lot  M-2649 or equivalent.
    6.3.2  2,6-Diphenylene oxide polymer--Tenax, (60/80 mesh), 
chromatographic grade or equivalent.
    6.3.3  Methyl silicone packing--3% OV-1 on Chromosorb-W (60/80 mesh) 
or equivalent.
    6.3.4  Silica gel--35/60 mesh, Davison, grade-15 or equivalent.
    6.4  Methanol--Pesticide quality or equivalent.
    6.5  Stock standard solutions--Stock standard solutions may be 
prepared from pure standard materials or purchased as certified 
solutions. Prepare stock standard solutions in methanol using assayed 
liquids or gases as appropriate. Because of the toxicity of some of the 
organohalides, primary dilutions of these materials should be prepared 
in a hood. A NIOSH/MESA approved toxic gas respirator should be used 
when the analyst handles high concentrations of such materials.
    6.5.1  Place about 9.8 mL of methanol into a 10-mL ground glass 
stoppered volumetric flask. Allow the flask to stand, unstoppered, for 
about 10 min or until all alcohol wetted surfaces have dried. Weigh the 
flask to the learest 0.1 mg.
    6.5.2  Add the assayed reference material:
    6.5.2.1  Liquid--Using a 100 [mu]L syringe, immediately add two or 
more drops of assayed reference material to the flask, then reweigh. Be 
sure that the drops fall directly into the alcohol without contacting 
the neck of the flask.
    6.5.2.2  Gases--To prepare standards for any of the six halocarbons 
that boil below 30  deg. C (bromomethane, chloroethane, chloromethane, 
dichlorodifluoromethane, trichlorofluoromethane, vinyl chloride), fill a 
5-mL valved gas-tight syringe with the reference standard to the 5.0-mL 
mark. Lower the needle to 5 mm above the methanol meniscus. Slowly 
introduce the reference standard above the surface of the liquid (the 
heavy gas will rapidly dissolve into the methanol).
    6.5.3  Reweigh, dilute to volume, stopper, then mix by inverting the 
flask several times. Calculate the concentration in [mu]g/[mu]L from the 
net gain in weight. When compound purity is assayed to be 96% or 
greater, the weight can be used without correction to calculate the 
concentration of the stock standard. Commercially prepared stock 
standards can be used at any concentration if they are certified by the 
malufacturer or by an independent source.
    6.5.4  Transfer the stock standard solution into a Teflon-sealed 
screw-cap bottle. Store, with minimal headspace, at -10 to -20  deg.C 
and protect from light.
    6.5.5  Prepare fresh standards weekly for the six gases and 2-
chloroethylvinyl ether. All other standards must be replaced after one 
month, or sooner if comparison with check standards indicates a problem.
    6.6  Secondary dilution standards--Using stock standard solutions, 
prepare secondary dilution standards in methanol that contain the 
compounds of interest, either singly or mixed together. The secondary 
dilution standards should be prepared at concentrations such that the 
aqueous calibration standards prepared in Section 7.3.1 or 7.4.1 will 
bracket the working range of the analytical system. Secondary dilution 
standards should be stored with minimal headspace and should be checked 
frequently for signs of degradation or evaporation, especially just 
prior to preparing calibration standards from them.
    6.7  Quality control check sample concentrate--See Section 8.2.1.

[[Page 34]]

                             7. Calibration

    7.1  Assemble a purge and trap system that meets the specifications 
in Section 5.2. Condition the trap overnight at 180  deg.C by 
backflushing with an inert gas flow of at least 20 mL/min. Condition the 
trap for 10 min once daily prior to use.
    7.2  Connect the purge and trap system to a gas chromatograph. The 
gas chromatograph must be operated using temperature and flow rate 
conditions equivalent to those given in Table 1. Calibrate the purge and 
trap-gas chromatographic system using either the external standard 
technique (Section 7.3) or the internal standard technique (Section 
7.4).
    7.3  External standard calibration procedure:
    7.3.1  Prepare calibration standards at a miminum of three 
concentration levels for each parameter by carefully adding 20.0 [mu]L 
of one or more secondary dilution standards to 100, 500, or 1000 [mu]L 
of reagent water. A 25-[mu]L syringe with a 0.006 in. ID needle should 
be used for this operation. One of the external standards should be at a 
concentration near, but above, the MDL (Table 1) and the other 
concentrations should correspond to the expected range of concentrations 
found in real samples or should define the working range of the 
detector. These aqueous standards can be stored up to 24 h, if held in 
sealed vials with zero headspace as described in Section 9.2. If not so 
stored, they must be discarded after 1 h.
    7.3.2  Analyze each calibration standard according to Section 10, 
and tabulate peak height or area responses versus the concentration in 
the standard. The results can be used to prepare a calibration curve for 
each compound. Alternatively, if the ratio of response to concentration 
(calibration factor) is a constant over the working range (<10% relative 
standard deviation, RSD), linearity through the origin can be assumed 
and the average ratio or calibration factor can be used in place of a 
calibration curve.
    7.4  Internal standard calibration procedure--To use this approach, 
the analyst must select one or more internal standards that are similar 
in analytical behavior to the compounds of interest. The analyst must 
further demonstrate that the measurement of the internal standard is not 
affected by method or matrix interferences. Because of these 
limitations, no internal standard can be suggested that is applicable to 
all samples. The compounds recommended for use as surrogate spikes in 
Section 8.7 have been used successfully as internal standards, because 
of their generally unique retention times.
    7.4.1  Prepare calibration standards at a minimum of three 
concentration levels for each parameter of interest as described in 
Section 7.3.1.
    7.4.2  Prepare a spiking solution containing each of the internal 
standards using the procedures described in Sections 6.5 and 6.6. It is 
recommended that the secondary dilution standard be prepared at a 
concentration of 15 [mu]g/mL of each internal standard compound. The 
addition of 10 [mu]L of this standard to 5.0 mL of sample or calibration 
standard would be equivalent to 30 [mu]g/L.
    7.4.3  Analyze each calibration standard according to Section 10, 
adding 10 [mu]L of internal standard spiking solution directly to the 
syringe (Section 10.4). Tabulate peak height or area responses against 
concentration for each compound and internal standard, and calculate 
response factors (RF) for each compound using Equation 1.
[GRAPHIC] [TIFF OMITTED] TC15NO91.094

                                                              Equation 1
where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Cis=Concentration of the internal standard.
Cs=Concentration of the parameter to be measured.

If the RF value over the working range is a constant (<10% RSD), the RF 
can be assumed to be invariant and the average RF can be used for 
calculations. Alternatively, the results can be used to plot a 
calibration curve of response ratios, As/Ais, vs. 
RF.
    7.5  The working calibration curve, calibration factor, or RF must 
be verified on each working day by the measurement of a QC check sample.
    7.5.1  Prepare the QC check sample as described in Section 8.2.2.
    7.5.2  Analyze the QC check sample according to Section 10.
    7.5.3  For each parameter, compare the response (Q) with the 
corresponding calibration acceptance criteria found in Table 2. If the 
responses for all parameters of interest fall within the designated 
ranges, analysis of actual samples can begin. If any individual Q falls 
outside the range, proceed according to Section 7.5.4.
    Note: The large number of parameters in Table 2 present a 
substantial probability that one or more will not meet the calibration 
acceptance criteria when all parameters are analyzed.
    7.5.4  Repeat the test only for those parameters that failed to meet 
the calibration acceptance criteria. If the response for a parameter 
does not fall within the range in this second test, a new calibration 
curve, calibration factor, or RF must be prepared for that parameter 
according to Section 7.3 or 7.4.

[[Page 35]]

                           8. Quality Control

    8.1  Each laboratory that uses this method is required to operate a 
formal quality control program. The minimum requirements of this program 
consist of an initial demonstration of laboratory capability and an 
ongoing analysis of spiked samples to evaluate and document data 
quality. The laboratory must maintain records to document the quality of 
data that is generated. Ongoing data quality checks are compared with 
established performance criteria to determine if the results of analyses 
meet the performance characteristics of the method. When results of 
sample spikes indicate atypical method performance, a quality control 
check standard must be analyzed to confirm that the measurements were 
performed in an in-control mode of operation.
    8.1.1  The analyst must make an initial, one-time, demonstration of 
the ability to generate acceptable accuracy and precision with this 
method. This ability is established as described in Section 8.2.
    8.1.2  In recognition of advances that are occurring in 
chromatography, the analyst is permitted certain options (detailed in 
Section 10.1) to improve the separations or lower the cost of 
measurements. Each time such a modification is made to the method, the 
analyst is required to repeat the procedure in Section 8.2.
    8.1.3  Each day, the analyst must analyze a reagent water blank to 
demonstrate that interferences from the analytical system are under 
control.
    8.1.4  The laboratory must, on an ongoing basis, spike and analyze a 
minimum of 10% of all samples to monitor and evaluate laboratory data 
quality. This procedure is described in Section 8.3.
    8.1.5  The laboratory must, on an ongoing basis, demonstrate through 
the analyses of quality control check standards that the operation of 
the measurement system is in control. This procedure is described in 
Section 8.4. The frequency of the check standard analyses is equivalent 
to 10% of all samples analyzed but may be reduced if spike recoveries 
from samples (Section 8.3) meet all specified quality control criteria.
    8.1.6  The laboratory must maintain performance records to document 
the quality of data that is generated. This procedure is described in 
Section 8.5.
    8.2  To establish the ability to generate acceptable accuracy and 
precision, the analyst must perform the following operations.
    8.2.1  A quality control (QC) check sample concentrate is required 
containing each parameter of interest at a concentration of 10 [mu]g/mL 
in methanol. The QC check sample concentrate must be obtained from the 
U.S. Environmental Protection Agency, Environmental Monitoring and 
Support Laboratory in Cincinnati, Ohio, if available. If not available 
from that source, the QC check sample concentrate must be obtained from 
another external source. If not available from either source above, the 
QC check sample concentrate must be prepared by the laboratory using 
stock standards prepared independently from those used for calibration.
    8.2.2  Prepare a QC check sample to contain 20 [mu]g/L of each 
parameter by adding 200 [mu]L of QC check sample concentrate to 100 mL 
of reagent water.
    8.2.3  Analyze four 5-mL aliquots of the well-mixed QC check sample 
according to Section 10.
    8.2.4  Calculate the average recovery (X) in [mu]g/L, and the 
standard deviation of the recovery (s) in [mu]g/L, for each parameter of 
interest using the four results.
    8.2.5  For each parameter compare s and X with the corresponding 
acceptance criteria for precision and accuracy, respectively, found in 
Table 2. If s and X for all parameters of interest meet the acceptance 
criteria, the system performance is acceptable and analysis of actual 
samples can begin. If any individual s exceeds the precision limit or 
any individual X falls outside the range for accuracy, then the system 
performance is unacceptable for that parameter.
    Note: The large number of parameters in Table 2 present a 
substantial probability that one or more will fail at least one of the 
acceptance criteria when all parameters are analyzed.
    8.2.6  When one or more of the parameters tested fail at least one 
of the acceptance criteria, the analyst must proceed according to 
Section 8.2.6.1 or 8.2.6.2.
    8.2.6.1  Locate and correct the source of the problem and repeat the 
test for all parameters of interest beginning with Section 8.2.3.
    8.2.6.2  Beginning with Section 8.2.3, repeat the test only for 
those parameters that failed to meet criteria. Repeated failure, 
however, will confirm a general problem with the measurement system. If 
this occurs, locate and correct the source of the problem and repeat the 
test for all compounds of interest beginning with Section 8.2.3.
    8.3  The laboratory must, on an ongoing basis, spike at least 10% of 
the samples from each sample site being monitored to assess accuracy. 
For laboratories analyzing one to ten samples per month, at least one 
spiked sample per month is required.
    8.3.1  The concentration of the spike in the sample should be 
determined as follows:
    8.3.1.1  If, as in compliance monitoring, the concentration of a 
specific parameter in the sample is being checked against a regulatory 
concentration limit, the spike should be at that limit or 1 to 5 times 
higher than the background concentration determined in Section 8.3.2, 
whichever concentration would be larger.

[[Page 36]]

    8.3.1.2  If the concentration of a specific parameter in the sample 
is not being checked against a limit specific to that parameter, the 
spike should be at 20 [mu]g/L or 1 to 5 times higher than the background 
concentration determined in Section 8.3.2, whichever concentration would 
be larger.
    8.3.2  Analyze one 5-mL sample aliquot to determine the background 
concentration (B) of each parameter. If necessary, prepare a new QC 
check sample concentrate (Section 8.2.1) appropriate for the background 
concentrations in the sample. Spike a second 5-mL sample aliquot with 10 
[mu]L of the QC check sample concentrate and analyze it to determine the 
concentration after spiking (A) of each parameter. Calculate each 
percent recovery (P) as 100(A-B)%/T, where T is the known true value of 
the spike.
    8.3.3  Compare the percent recovery (P) for each parameter with the 
corresponding QC acceptance criteria found in Table 2. These acceptance 
criteria were calculated to include an allowance for error in 
measurement of both the background and spike concentrations, assuming a 
spike to background ratio of 5:1. This error will be accounted for to 
the extent that the analyst's spike to background ratio approaches 
5:1.7 If spiking was performed at a concentration lower than 
20 [mu]g/L, the analyst must use either the QC acceptance criteria in 
Table 2, or optional QC acceptance criteria calculated for the specific 
spike concentration. To calculate optional acceptance criteria for the 
recovery of a parameter: (1) Calculate accuracy (X') using the equation 
in Table 3, substituting the spike concentration (T) for C; (2) 
calculate overall precision (S') using the equation in Table 3, 
substituting X' for X; (3) calculate the range for recovery at the spike 
concentration as (100 X'/T)2.44(100 S'/T)%.7
    8.3.4  If any individual P falls outside the designated range for 
recovery, that parameter has failed the acceptance criteria. A check 
standard containing each parameter that failed the criteria must be 
analyzed as described in Section 8.4.
    8.4  If any parameter fails the acceptance criteria for recovery in 
Section 8.3, a QC check standard containing each parameter that failed 
must be prepared and analyzed.
    Note: The frequency for the required analysis of a QC check standard 
will depend upon the number of parameters being simultaneously tested, 
the complexity of the sample matrix, and the performance of the 
laboratory. If the entire list of parameters in Table 2 must be measured 
in the sample in Section 8.3, the probability that the analysis of a QC 
check standard will be required is high. In this case the QC check 
standard should be routinely analyzed with the spiked sample.
    8.4.1  Prepare the QC check standard by adding 10 [mu]L of QC check 
sample concentrate (Section 8.2.1 or 8.3.2) to 5 mL of reagent water. 
The QC check standard needs only to contain the parameters that failed 
criteria in the test in Section 8.3.
    8.4.2  Analyze the QC check standard to determine the concentration 
measured (A) of each parameter. Calculate each percent recovery 
(Ps) as 100 (A/T)%, where T is the true value of the standard 
concentration.
    8.4.3  Compare the percent recovery (Ps) for each 
parameter with the corresponding QC acceptance criteria found in Table 
2. Only parameters that failed the test in Section 8.3 need to be 
compared with these criteria. If the recovery of any such parameter 
falls outside the designated range, the laboratory performance for that 
parameter is judged to be out of control, and the problem must be 
immediately identified and corrected. The analytical result for that 
parameter in the unspiked sample is suspect and may not be reported for 
regulatory compliance purposes.
    8.5  As part of the QC program for the laboratory, method accuracy 
for wastewater samples must be assessed and records must be maintained. 
After the analysis of five spiked wastewater samples as in Section 8.3, 
calculate the average percent recovery (P) and the standard deviation of 
the percent recovery (sp). Express the accuracy assessment as 
a percent recovery interval from P-2sp to P+2sp. 
If p=90% and sp=10%, for example, the accuracy interval is 
expressed as 70-110%. Update the accuracy assessment for each parameter 
on a regular basis (e.g. after each five to ten new accuracy 
measurements).
    8.6  It is recommended that the laboratory adopt additional quality 
assurance practices for use with this method. The specific practices 
that are most productive depend upon the needs of the laboratory and the 
nature of the samples. Field duplicates may be analyzed to assess the 
precision of the environmental measurements. When doubt exists over the 
identification of a peak on the chromatogram, confirmatory techniques 
such as gas chromatography with a dissimilar column, specific element 
detector, or mass spectrometer must be used. Whenever possible, the 
laboratory should analyze standard reference materials and participate 
in relevant performance evaluation studies.
    8.7  The analyst should monitor both the performance of the 
analytical system and the effectiveness of the method in dealing with 
each sample matrix by spiking each sample, standard, and reagent water 
blank with surrogate halocarbons. A combination of bromochloromethane, 
2-bromo-1-chloropropane, and 1,4-dichlorobutane is recommended to 
encompass the range of the temperature program used in this method. From 
stock standard solutions prepared as in Section 6.5, add a volume to 
give 750 [mu]g of each surrogate to 45 mL of reagent water contained in 
a 50-mL volumetric flask, mix and dilute to volume for a concentration 
of 15 ng/[mu]L. Add 10 [mu]L of this surrogate spiking solution directly 
into the 5-mL syringe with

[[Page 37]]

every sample and reference standard analyzed. Prepare a fresh surrogate 
spiking solution on a weekly basis. If the internal standard calibration 
procedure is being used, the surrogate compounds may be added directly 
to the internal standard spiking solution (Section 7.4.2).

            9. Sample Collection, Preservation, and Handling

    9.1  All samples must be iced or refrigerated from the time of 
collection until analysis. If the sample contains free or combined 
chlorine, add sodium thiosulfate preservative (10 mg/40 mL is sufficient 
for up to 5 ppm Cl2) to the empty sample bottle just prior to 
shipping to the sampling site. EPA Methods 330.4 and 330.5 may be used 
for measurement of residual chlorine.8 Field test kits are 
available for this purpose.
    9.2  Grab samples must be collected in glass containers having a 
total volume of at least 25 mL. Fill the sample bottle just to 
overflowing in such a manner that no air bubbles pass through the sample 
as the bottle is being filled. Seal the bottle so that no air bubbles 
are entrapped in it. If preservative has been added, shake vigorously 
for 1 min. Maintain the hermetic seal on the sample bottle until time of 
analysis.
    9.3  All samples must be analyzed within 14 days of 
collection.3

                              10. Procedure

    10.1  Table 1 summarizes the recommended operating conditions for 
the gas chromatograph. Included in this table are estimated retention 
times and MDL that can be achieved under these conditions. An example of 
the separations achieved by Column 1 is shown in Figure 5. Other packed 
columns, chromatographic conditions, or detectors may be used if the 
requirements of Section 8.2 are met.
    10.2  Calibrate the system daily as described in Section 7.
    10.3  Adjust the purge gas (nitrogen or helium) flow rate to 40 mL/
min. Attach the trap inlet to the purging device, and set the purge and 
trap system to purge (Figure 3). Open the syringe valve located on the 
purging device sample introduction needle.
    10.4  Allow the sample to come to ambient temperature prior to 
introducing it to the syringe. Remove the plunger from a 5-mL syringe 
and attach a closed syringe valve. Open the sample bottle (or standard) 
and carefully pour the sample into the syringe barrel to just short of 
overflowing. Replace the syringe plunger and compress the sample. Open 
the syringe valve and vent any residual air while adjusting the sample 
volume to 5.0 mL. Since this process of taking an aliquot destroys the 
validity of the sample for future analysis, the analyst should fill a 
second syringe at this time to protect against possible loss of data. 
Add 10.0 [mu]L of the surrogate spiking solution (Section 8.7) and 10.0 
[mu]L of the internal standard spiking solution (Section 7.4.2), if 
applicable, through the valve bore, then close the valve.
    10.5  Attach the syringe-syringe valve assembly to the syringe valve 
on the purging device. Open the syringe valves and inject the sample 
into the purging chamber.
    10.6  Close both valves and purge the sample for 11.00.1 
min at ambient temperature.
    10.7  After the 11-min purge time, attach the trap to the 
chromatograph, adjust the purge and trap system to the desorb mode 
(Figure 4), and begin to temperature program the gas chromatograph. 
Introduce the trapped materials to the GC column by rapidly heating the 
trap to 180  deg.C while backflushing the trap with an inert gas between 
20 and 60 mL/min for 4 min. If rapid heating of the trap cannot be 
achieved, the GC column must be used as a secondary trap by cooling it 
to 30  deg.C (subambient temperature, if poor peak geometry or random 
retention time problems persist) instead of the initial program 
temperature of 45  deg.C
    10.8  While the trap is being desorbed into the gas chromatograph, 
empty the purging chamber using the sample introduction syringe. Wash 
the chamber with two 5-mL flushes of reagent water.
    10.9  After desorbing the sample for 4 min, recondition the trap by 
returning the purge and trap system to the purge mode. Wait 15 s then 
close the syringe valve on the purging device to begin gas flow through 
the trap. The trap temperature should be maintained at 180  deg.C After 
approximately 7 min, turn off the trap heater and open the syringe valve 
to stop the gas flow through the trap. When the trap is cool, the next 
sample can be analyzed.
    10.10  Identify the parameters in the sample by comparing the 
retention times of the peaks in the sample chromatogram with those of 
the peaks in standard chromatograms. The width of the retention time 
window used to make identifications should be based upon measurements of 
actual retention time variations of standards over the course of a day. 
Three times the standard deviation of a retention time for a compound 
can be used to calculate a suggested window size; however, the 
experience of the analyst should weigh heavily in the interpretation of 
chromatograms.
    10.11  If the response for a peak exceeds the working range of the 
system, prepare a dilution of the sample with reagent water from the 
aliquot in the second syringe and reanalyze.

                            11. Calculations

    11.1  Determine the concentration of individual compounds in the 
sample.

[[Page 38]]

    11.1.1  If the external standard calibration procedure is used, 
calculate the concentration of the parameter being measured from the 
peak response using the calibration curve or calibration factor 
determined in Section 7.3.2.
    11.1.2  If the internal standard calibration procedure is used, 
calculate the concentration in the sample using the response factor (RF) 
determined in Section 7.4.3 and Equation 2.
                                                              Equation 2
[GRAPHIC] [TIFF OMITTED] TC15NO91.095

where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Cis=Concentration of the internal standard.

    11.2  Report results in [mu]g/L without correction for recovery 
data. All QC data obtained should be reported with the sample results.

                         12. Method Performance

    12.1 The method detection limit (MDL) is defined as the minimum 
concentration of a substance that can be measured and reported with 99% 
confidence that the value is above zero. \1\ The MDL concentration 
listed in Table 1 were obtained using reagent water.11. 
Similar results were achieved using representative wastewaters. The MDL 
actually achieved in a given analysis will vary depending on instrument 
sensitivity and matrix effects.

    12.2  This method is recommended for use in the concentration range 
from the MDL to 1000xMDL. Direct aqueous injection techniques should be 
used to measure concentration levels above 1000xMDL.
    12.3  This method was tested by 20 laboratories using reagent water, 
drinking water, surface water, and three industrial wastewaters spiked 
at six concentrations over the range 8.0 to 500 [mu]g/L.9 
Single operator precision, overall precision, and method accuracy were 
found to be directly related to the concentration of the parameter and 
essentially independent of the sample matrix. Linear equations to 
describe these relationships are presented in Table 3.

                               References

    1. 40 CFR part 136, appendix B.
    2. Bellar, T.A., and Lichtenberg, J.J. ``Determining Volatile 
Organics at Microgram-per-Litre-Levels by Gas Chromatography,'' Journal 
of the American Water Works Association, 66, 739 (1974).
    3. Bellar, T.A., and Lichtenberg, J.J. ``Semi-Automated Headspace 
Analysis of Drinking Waters and Industrial Waters for Purgeable Volatile 
Organic Compounds,'' Proceedings from Symposium on Measurement of 
Organic Pollutants in Water and Wastewater, American Society for Testing 
and Materials, STP 686, C.E. Van Hall, editor, 1978.
    4. ``Carcinogens--Working With Carcinogens,'' Department of Health, 
Education, and Welfare, Public Health Service, Center for Disease 
Control, National Institute for Occupational Safety and Health, 
Publication No. 77-206, August 1977.
    5. ``OSHA Safety and Health Standards, General Industry'' (29 CFR 
part 1910), Occupational Safety and Health Administration, OSHA 2206 
(Revised, January 1976).
    6. ``Safety in Academic Chemistry Laboratories,'' American Chemical 
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
    7. Provost, L.P., and Elder, R.S. ``Interpretation of Percent 
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44 
used in the equation in Section 8.3.3 is two times the value 1.22 
derived in this report.)
    8. ``Methods 330.4 (Titrimetric, DPD-FAS) and 330.5 
(Spectrophotometric, DPD) for Chlorine, Total Residual,'' Methods for 
Chemical Analysis of Water and Wastes, EPA 600/4-79-020, U.S. 
Environmental Protection Agency, Environmental Monitoring and Support 
Laboratory, Cincinnati, Ohio 45268, March 1979.
    9. ``EPA Method Study 24, Method 601--Purgeable Halocarbons by the 
Purge and Trap Method,'' EPA 600/4-84-064, National Technical 
Information Service, PB84-212448, Springfield, Virginia 22161, July 
1984.
    10. ``Method Validation Data for EPA Method 601,'' Memorandum from 
B. Potter, U.S. Environmental Protection Agency, Environmental 
Monitoring and Support Laboratory, Cincinnati, Ohio 45268, November 10, 
1983.
    11. Bellar, T. A., Unpublished data, U.S. Environmental Protection 
Agency, Environmental Monitoring and Support Laboratory, Cincinnati, 
Ohio 45268, 1981.

                         Table 1--Chromatographic Conditions and Method Detection Limits
----------------------------------------------------------------------------------------------------------------
                                                                   Retention time (min)
                         Parameter                         ------------------------------------ Method detection
                                                                Column 1          Column 2       limit ([mu]g/L)
----------------------------------------------------------------------------------------------------------------
Chloromethane.............................................         1.50              5.28              0.08
Bromomethane..............................................         2.17              7.05              1.18
Dichlorodifluoromethane...................................         2.62             nd                 1.81

[[Page 39]]

 
Vinyl chloride............................................         2.67              5.28              0.18
Chloroethane..............................................         3.33              8.68              0.52
Methylene chloride........................................         5.25             10.1               0.25
Trichlorofluoromethane....................................         7.18             nd                nd
1,1-Dichloroethene........................................         7.93              7.72              0.13
1,1-Dichloroethane........................................         9.30             12.6               0.07
trans-1,2-Dichloroethene..................................        10.1               9.38              0.10
Chloroform................................................        10.7              12.1               0.05
1,2-Dichloroethane........................................        11.4              15.4               0.03
1,1,1-Trichloroethane.....................................        12.6              13.1               0.03
Carbon tetrachloride......................................        13.0              14.4               0.12
Bromodichloromethane......................................        13.7              14.6               0.10
1,2-Dichloropropane.......................................        14.9              16.6               0.04
cis-1,3-Dichloropropene...................................        15.2              16.6               0.34
Trichloroethene...........................................        15.8              13.1               0.12
Dibromochloromethane......................................        16.5              16.6               0.09
1,1,2-Trichloroethane.....................................        16.5              18.1               0.02
trans-1,3-Dichloropropene.................................        16.5              18.0               0.20
2-Chloroethylvinyl ether..................................        18.0              nd                 0.13
Bromoform.................................................        19.2              19.2               0.20
1,1,2,2-Tetrachloroethane.................................        21.6              nd                 0.03
Tetrachloroethene.........................................        21.7              15.0               0.03
Chlorobenzene.............................................        24.2              18.8               0.25
1,3-Dichlorobenzene.......................................        34.0              22.4               0.32
1,2-Dichlorobenzene.......................................        34.9              23.5               0.15
1,4-Dichlorobenzene.......................................        35.4              22.3               0.24
----------------------------------------------------------------------------------------------------------------
Column 1 conditions: Carbopack B (60/80 mesh) coated with 1% SP-1000 packed in an 8 ft x 0.1 in. ID stainless
  steel or glass column with helium carrier gas at 40 mL/min flow rate. Column temperature held at 45  deg.C for
  3 min then programmed at 8  deg.C/min to 220  deg.C and held for 15 min.
Column 2 conditions: Porisil-C (100/120 mesh) coated with n-octane packed in a 6 ft x 0.1 in. ID stainless steel
  or glass column with helium carrier gas at 40 mL/min flow rate. Column temperature held at 50  deg.C for 3 min
  then programmed at 6  deg.C/min to 170  deg.C and held for 4 min.
nd=not determined.


                          Table 2--Calibration and QC Acceptance Criteria--Method 601 a
----------------------------------------------------------------------------------------------------------------
                                                                           Limit for
                        Parameter                           Range for Q    s ([mu]g/    Range for X    Range P,
                                                             ([mu]g/L)        L)         ([mu]g/L)      Ps (%)
----------------------------------------------------------------------------------------------------------------
Bromodichloromethane....................................       15.2-24.8         4.3       10.7-32.0      42-172
Bromoform...............................................       14.7-25.3         4.7        5.0-29.3      13-159
Bromomethane............................................       11.7-28.3         7.6        3.4-24.5       D-144
Carbon tetrachloride....................................       13.7-26.3         5.6       11.8-25.3      43-143
Chlorobenzene...........................................       14.4-25.6         5.0       10.2-27.4      38-150
Chloroethane............................................       15.4-24.6         4.4       11.3-25.2      46-137
2-Chloroethylvinyl ether................................       12.0-28.0         8.3        4.5-35.5      14-186
Chloroform..............................................       15.0-25.0         4.5       12.4-24.0      49-133
Chloromethane...........................................       11.9-28.1         7.4          D-34.9       D-193
Dibromochloromethane....................................       13.1-26.9         6.3        7.9-35.1      24-191
1,2-Dichlorobenzene.....................................       14.0-26.0         5.5        1.7-38.9       D-208
1,3-Dichlorobenzene.....................................        9.9-30.1         9.1        6.2-32.6       7-187
1,4-Dichlorobenzene.....................................       13.9-26.1         5.5       11.5-25.5      42-143
1,1-Dichloroethane......................................       16.8-23.2         3.2       11.2-24.6      47-132
1,2-Dichloroethane......................................       14.3-25.7         5.2       13.0-26.5      51-147
1,1-Dichloroethene......................................       12.6-27.4         6.6       10.2-27.3      28-167
trans-1,2-Dichloroethene................................       12.8-27.2         6.4       11.4-27.1      38-155
1,2-Dichloropropane.....................................       14.8-25.2         5.2       10.1-29.9      44-156
cis-1,3-Dichloropropene.................................       12.8-27.2         7.3        6.2-33.8      22-178
trans-1,3-Dichloropropene...............................       12.8-27.2         7.3        6.2-33.8      22-178
Methylene chloride......................................       15.5-24.5         4.0        7.0-27.6      25-162
1,1,2,2-Tetrachloroethane...............................        9.8-30.2         9.2        6.6-31.8       8-184
Tetrachloroethene.......................................       14.0-26.0         5.4        8.1-29.6      26-162
1,1,1-Trichloroethane...................................       14.2-25.8         4.9       10.8-24.8      41-138
1,1,2-Trichloroethane...................................       15.7-24.3         3.9        9.6-25.4      39-136
Trichloroethene.........................................       15.4-24.6         4.2        9.2-26.6      35-146
Trichlorofluoromethane..................................       13.3-26.7         6.0        7.4-28.1      21-156
Vinyl chloride..........................................       13.7-26.3         5.7        8.2-29.9      28-163
----------------------------------------------------------------------------------------------------------------
a Criteria were calculated assuming a QC check sample concentration of 20 [mu]g/L.
Q=Concentration measured in QC check sample, in [mu]g/L (Section 7.5.3).
s=Standard deviation of four recovery measurements, in [mu]g/L (Section 8.2.4).

[[Page 40]]

 
X=Average recovery for four recovery measurements, in [mu]g/L (Section 8.2.4).
P, Ps=Percent recovery measured (Section 8.3.2, Section 8.4.2).
D=Detected; result must be greater than zero.
 
Note: These criteria are based directly upon the method performance data in Table 3. Where necessary, the limits
  for recovery have been broadened to assure applicability of the limits to concentrations below those used to
  develop Table 3.


                Table 3.--Method Accuracy and Precision as Functions of Concentration--Method 601
----------------------------------------------------------------------------------------------------------------
                                                                     Single analyst
              Parameter                Accuracy, as recovery,    precision, sr' ([mu]g/   Overall precision, S'
                                            X' ([mu]g/L)                   L)                   ([mu]g/L)
----------------------------------------------------------------------------------------------------------------
Bromodichloromethane................  1.12C-1.02                0.11X+0.04               0.20X+1.00
Bromoform...........................  0.96C-2.05                0.12X+0.58               0.21X+2.41
Bromomethane........................  0.76C-1.27                0.28X+0.27               0.36X+0.94
Carbon tetrachloride................  0.98C-1.04                0.15X+0.38               0.20X+0.39
Chlorobenzene.......................  1.00C-1.23                0.15X-0.02               0.18X+1.21
Choroethane.........................  0.99C-1.53                0.14X-0.13               0.17X+0.63
2-Chloroethylvinyl ether a .........  1.00C                     0.20X                    0.35X
Chloroform..........................  0.93C-0.39                0.13X+0.15               0.19X-0.02
Chloromethane.......................  0.77C+0.18                0.28X-0.31               0.52X+1.31
Dibromochloromethane................  0.94C+2.72                0.11X+1.10               0.24X+1.68
1,2-Dichlorobenzene.................  0.93C+1.70                0.20X+0.97               0.13X+6.13
1,3-Dichlorobenzene.................  0.95C+0.43                0.14X+2.33               0.26X+2.34
1,4-Dichlorobenzene.................  0.93C-0.09                0.15X+0.29               0.20X+0.41
1,1-Dichloroethane..................  0.95C-1.08                0.09X+0.17               0.14X+0.94
1,2-Dichloroethane..................  1.04C-1.06                0.11X+0.70               0.15X+0.94
1,1-Dichloroethene..................  0.98C-0.87                0.21X-0.23               0.29X-0.40
trans-1,2-Dichloroethene............  0.97C-0.16                0.11X+1.46               0.17X+1.46
1,2-Dichloropropane a ..............  1.00C                     0.13X                    0.23X
cis-1,3-Dichloropropene a ..........  1.00C                     0.18X                    0.32X
trans-1,3-Dichloropropene a ........  1.00C                     0.18X                    0.32X
Methylene chloride..................  0.91C-0.93                0.11X+0.33               0.21X+1.43
1,1,2,2-Tetrachloroethene...........  0.95C+0.19                0.14X+2.41               0.23X+2.79
Tetrachloroethene...................  0.94C+0.06                0.14X+0.38               0.18X+2.21
1,1,1-Trichloroethane...............  0.90C-0.16                0.15X+0.04               0.20X+0.37
1,1,2-Trichloroethane...............  0.86C+0.30                0.13X-0.14               0.19X+0.67
Trichloroethene.....................  0.87C+0.48                0.13X-0.03               0.23X+0.30
Trichlorofluoromethane..............  0.89C-0.07                0.15X+0.67               0.26X+0.91
Vinyl chloride......................  0.97C-0.36                0.13X+0.65               0.27X+0.40
----------------------------------------------------------------------------------------------------------------
X'=Expected recovery for one or more measurements of a sample containing a concentration of C, in [mu]g/L.
sn'=Expected single analyst standard deviation of measurements at an average concentration found of X, in [mu]g/
  L.
S\1\=Expected interlaboratory standard deviation of measurements at an average concentration found of X, in
  [mu]g/L.
C=True value for the concentration, in [mu]g/L.
X=Average recovery found for measurements of samples containing a concentration of C, in [mu]g/L.
a Estimates based upon the performance in a single laboratory.\10\


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[[Page 45]]

                     Method 602--Purgeable Aromatics

                        1. Scope and Application

    1.1  This method covers the determination of various purgeable 
aromatics. The following parameters may be determined by this method:

------------------------------------------------------------------------
                                                    STORET
                    Parameter                         No.      CAS No.
------------------------------------------------------------------------
Benzene..........................................     34030      71-43-2
Chlorobenzene....................................     34301     108-90-7
1,2-Dichlorobenzene..............................     34536      95-50-1
1,3-Dichlorobenzene..............................     34566     541-73-1
1,4-Dichlorobenzene..............................     34571     106-46-7
Ethylbenzene.....................................     34371     100-41-4
Toluene..........................................     34010     108-88-3
------------------------------------------------------------------------

    1.2  This is a purge and trap gas chromatographic (GC) method 
applicable to the determination of the compounds listed above in 
municipal and industrial discharges as provided under 40 CFR 136.1. When 
this method is used to analyze unfamiliar samples for any or all of the 
compounds above, compound identifications should be supported by at 
least one additional qualitative technique. This method describes 
analytical conditions for a second gas chromatographic column that can 
be used to confirm measurements made with the primary column. Method 624 
provides gas chromatograph/mass spectrometer (GC/MS) conditions 
appropriate for the qualitative and quantitative confirmation of results 
for all of the parameters listed above.
    1.3  The method detection limit (MDL, defined in Section 12.1) 
1 for each parameter is listed in Table 1. The MDL for a 
specific wastewater may differ from those listed, depending upon the 
nature of interferences in the sample matrix.
    1.4  Any modification of this method, beyond those expressly 
permitted, shall be considered as a major modification subject to 
application and approval of alternate test procedures under 40 CFR 136.4 
and 136.5.
    1.5  This method is restricted to use by or under the supervision of 
analysts experienced in the operation of a purge and trap system and a 
gas chromatograph and in the interpretation of gas chromatograms. Each 
analyst must demonstrate the ability to generate acceptable results with 
this method using the procedure described in Section 8.2.

                          2. Summary of Method

    2.1  An inert gas is bubbled through a 5-mL water sample contained 
in a specially-designed purging chamber at ambient temperature. The 
aromatics are efficiently transferred from the aqueous phase to the 
vapor phase. The vapor is swept through a sorbent trap where the 
aromatics are trapped. After purging is completed, the trap is heated 
and backflushed with the inert gas to desorb the aromatics onto a gas 
chromatographic column. The gas chromatograph is temperature programmed 
to separate the aromatics which are then detected with a photoionization 
detector.2, 3
    2.2  The method provides an optional gas chromatographic column that 
may be helpful in resolving the compounds of interest from interferences 
that may occur.

                            3. Interferences

    3.1  Impurities in the purge gas and organic compounds outgassing 
from the plumbing ahead of the trap account for the majority of 
contamination problems. The analytical system must be demonstrated to be 
free from contamination under the conditions of the analysis by running 
laboratory reagent blanks as described in Section 8.1.3. The use of non-
Teflon plastic tubing, non-Teflon thread sealants, or flow controllers 
with rubber components in the purge and trap system should be avoided.
    3.2  Samples can be contaminated by diffusion of volatile organics 
through the septum seal into the sample during shipment and storage. A 
field reagent blank prepared from reagent water and carried through the 
sampling and handling protocol can serve as a check on such 
contamination.
    3.3  Contamination by carry-over can occur whenever high level and 
low level samples are sequentially analyzed. To reduce carry-over, the 
purging device and sample syringe must be rinsed with reagent water 
between sample analyses. Whenever an unusually concentrated sample is 
encountered, it should be followed by an analysis of reagent water to 
check for cross contamination. For samples containing large amounts of 
water-soluble materials, suspended solids, high boiling compounds or 
high aromatic levels, it may be necessary to wash the purging device 
with a detergent solution, rinse it with distilled water, and then dry 
it in an oven at 105  deg.C between analyses. The trap and other parts 
of the system are also subject to contamination; therefore, frequent 
bakeout and purging of the entire system may be required.

                                4. Safety

    4.1  The toxicity or carcinogenicity of each reagent used in this 
method has not been precisely defined; however, each chemical compound 
should be treated as a potential health hazard. From this viewpoint, 
exposure to these chemicals must be reduced to the lowest possible level 
by whatever means available. The laboratory is responsible for 
maintaining a current awareness file of OSHA regulations regarding the 
safe handling of the chemicals specified in this method. A reference 
file of material data handling sheets should also be made available to 
all personnel involved in the chemical analysis. Additional references 
to laboratory safety

[[Page 46]]

are available and have been identified 4-6 for the 
information of the analyst.
    4.2  The following parameters covered by this method have been 
tentatively classified as known or suspected, human or mammalian 
carcinogens: benzene and 1,4-dichlorobenzene. Primary standards of these 
toxic compounds should be prepared in a hood. A NIOSH/MESA approved 
toxic gas respirator should be worn when the analyst handles high 
concentrations of these toxic compounds.

                       5. Apparatus and Materials

    5.1  Sampling equipment, for discrete sampling.
    5.1.1  Vial]25-mL capacity or larger, equipped with a screw cap with 
a hole in the center (Pierce 13075 or equivalent). Detergent 
wash, rinse with tap and distilled water, and dry at 105  deg.C before 
use.
    5.1.2  Septum--Teflon-faced silicone (Pierce 12722 or 
equivalent). Detergent wash, rinse with tap and distilled water, and dry 
at 105  deg.C for 1 h before use.
    5.2  Purge and trap system--The purge and trap system consists of 
three separate pieces of equipment: A purging device, trap, and 
desorber. Several complete systems are now commercially available.
    5.2.1  The purging device must be designed to accept 5-mL samples 
with a water column at least 3 cm deep. The gaseous head space between 
the water column and the trap must have a total volume of less than 15 
mL. The purge gas must pass through the water column as finely divided 
bubbles with a diameter of less than 3 mm at the origin. The purge gas 
must be introduced no more than 5 mm from the base of the water column. 
The purging device illustrated in Figure 1 meets these design criteria.
    5.2.2  The trap must be at least 25 cm long and have an inside 
diameter of at least 0.105 in.
    5.2.2.1  The trap is packed with 1 cm of methyl silicone coated 
packing (Section 6.4.2) and 23 cm of 2,6-diphenylene oxide polymer 
(Section 6.4.1) as shown in Figure 2. This trap was used to develop the 
method performance statements in Section 12.
    5.2.2.2  Alternatively, either of the two traps described in Method 
601 may be used, although water vapor will preclude the measurement of 
low concentrations of benzene.
    5.2.3  The desorber must be capable of rapidly heating the trap to 
180  deg.C. The polymer section of the trap should not be heated higher 
than 180  deg.C and the remaining sections should not exceed 200  deg.C. 
The desorber illustrated in Figure 2 meets these design criteria.
    5.2.4  The purge and trap system may be assembled as a separate unit 
or be coupled to a gas chromatograph as illustrated in Figures 3, 4, and 
5.
    5.3  Gas chromatograph--An analytical system complete with a 
temperature programmable gas chromatograph suitable for on-column 
injection and all required accessories including syringes, analytical 
columns, gases, detector, and strip-chart recorder. A data system is 
recommended for measuring peak areas.
    5.3.1  Column 1--6 ft long x 0.082 in. ID stainless steel or glass, 
packed with 5% SP-1200 and 1.75% Bentone-34 on Supelcoport (100/120 
mesh) or equivalent. This column was used to develop the method 
performance statements in Section 12. Guidelines for the use of 
alternate column packings are provided in Section 10.1.
    5.3.2  Column 2--8 ft long x 0.1 in ID stainless steel or glass, 
packed with 5% 1,2,3-Tris(2-cyanoethoxy)propane on Chromosorb W-AW (60/
80 mesh) or equivalent.
    5.3.3  Detector--Photoionization detector (h-Nu Systems, Inc. Model 
PI-51-02 or equivalent). This type of detector has been proven effective 
in the analysis of wastewaters for the parameters listed in the scope 
(Section 1.1), and was used to develop the method performance statements 
in Section 12. Guidelines for the use of alternate detectors are 
provided in Section 10.1.
    5.4  Syringes--5-mL glass hypodermic with Luerlok tip (two each), if 
applicable to the purging device.
    5.5  Micro syringes--25-[mu]L, 0.006 in. ID needle.
    5.6  Syringe valve--2-way, with Luer ends (three each).
    5.7  Bottle--15-mL, screw-cap, with Teflon cap liner.
    5.8  Balance--Analytical, capable of accurately weighing 0.0001 g.

                               6. Reagents

    6.1  Reagent water--Reagent water is defined as a water in which an 
interferent is not observed at the MDL of the parameters of interest.
    6.1.1  Reagent water can be generated by passing tap water through a 
carbon filter bed containing about 1 lb of activated carbon (Filtrasorb-
300, Calgon Corp., or equivalent).
    6.1.2  A water purification system (Millipore Super-Q or equivalent) 
may be used to generate reagent water.
    6.1.3  Reagent water may also be prepared by boiling water for 15 
min. Subsequently, while maintaining the temperature at 90  deg.C, 
bubble a contaminant-free inert gas through the water for 1 h. While 
still hot, transfer the water to a narrow mouth screw-cap bottle and 
seal with a Teflon-lined septum and cap.
    6.2  Sodium thiosulfate--(ACS) Granular.
    6.3  Hydrochloric acid (1+1)--Add 50 mL of concentrated HCl (ACS) to 
50 mL of reagent water.
    6.4  Trap Materials:

[[Page 47]]

    6.4.1  2,6-Diphenylene oxide polymer--Tenax, (60/80 mesh), 
chromatographic grade or equivalent.
    6.4.2  Methyl silicone packing--3% OV-1 on Chromosorb-W (60/80 mesh) 
or equivalent.
    6.5  Methanol--Pesticide quality or equivalent.
    6.6  Stock standard solutions--Stock standard solutions may be 
prepared from pure standard materials or purchased as certified 
solutions. Prepare stock standard solutions in methanol using assayed 
liquids. Because of the toxicity of benzene and 1,4-dichlorobenzene, 
primary dilutions of these materials should be prepared in a hood. A 
NIOSH/MESA approved toxic gas respirator should be used when the analyst 
handles high concentrations of such materials.
    6.6.1  Place about 9.8 mL of methanol into a 10-mL ground glass 
stoppered volumetric flask. Allow the flask to stand, unstoppered, for 
about 10 min or until all alcohol wetted surfaces have dried. Weigh the 
flask to the nearest 0.1 mg.
    6.6.2  Using a 100-[mu]L syringe, immediately add two or more drops 
of assayed reference material to the flask, then reweigh. Be sure that 
the drops fall directly into the alcohol without contacting the neck of 
the flask.
    6.6.3  Reweigh, dilute to volume, stopper, then mix by inverting the 
flask several times. Calculate the concentration in [mu]g/[mu]L from the 
net gain in weight. When compound purity is assayed to be 96% or 
greater, the weight can be used without correction to calculate the 
concentration of the stock standard. Commercially prepared stock 
standards can be used at any concentration if they are certified by the 
manufacturer or by an independent source.
    6.6.4  Transfer the stock standard solution into a Teflon-sealed 
screw-cap bottle. Store at 4  deg.C and protect from light.
    6.6.5  All standards must be replaced after one month, or sooner if 
comparison with check standards indicates a problem.
    6.7  Secondary dilution standards--Using stock standard solutions, 
prepare secondary dilution standards in methanol that contain the 
compounds of interest, either singly or mixed together. The secondary 
dilution standards should be prepared at concentrations such that the 
aqueous calibration standards prepared in Section 7.3.1 or 7.4.1 will 
bracket the working range of the analytical system. Secondary solution 
standards must be stored with zero headspace and should be checked 
frequently for signs of degradation or evaporation, especially just 
prior to preparing calibration standards from them.
    6.8  Quality control check sample concentrate--See Section 8.2.1.

                             7.  Calibration

    7.1  Assemble a purge and trap system that meets the specifications 
in Section 5.2. Condition the trap overnight at 180  deg.C by 
backflushing with an inert gas flow of at least 20 mL/min. Condition the 
trap for 10 min once daily prior to use.
    7.2  Connect the purge and trap system to a gas chromatograph. The 
gas chromatograph must be operated using temperature and flow rate 
conditions equivalent to those given in Table 1. Calibrate the purge and 
trap-gas chromatographic system using either the external standard 
technique (Section 7.3) or the internal standard technique (Section 
7.4).
    7.3  External standard calibration procedure:
    7.3.1  Prepare calibration standards at a minimum of three 
concentration levels for each parameter by carefully adding 20.0 [mu]L 
of one or more secondary dilution standards to 100, 500, or 1000 mL of 
reagent water. A 25-[mu]L syringe with a 0.006 in. ID needle should be 
used for this operation. One of the external standards should be at a 
concentration near, but above, the MDL (Table 1) and the other 
concentrations should correspond to the expected range of concentrations 
found in real samples or should define the working range of the 
detector. These aqueous standards must be prepared fresh daily.
    7.3.2  Analyze each calibration standard according to Section 10, 
and tabulate peak height or area responses versus the concentration in 
the standard. The results can be used to prepare a calibration curve for 
each compound. Alternatively, if the ratio of response to concentration 
(calibration factor) is a constant over the working range (<10% relative 
standard deviation, RSD), linearity through the origin can be assumed 
and the average ratio or calibration factor can be used in place of a 
calibration curve.
    7.4  Internal standard calibration procedure--To use this approach, 
the analyst must select one or more internal standards that are similar 
in analytical behavior to the compounds of interest. The analyst must 
further demonstrate that the measurement of the internal standard is not 
affected by method or matrix interferences. Because of these 
limitations, no internal standard can be suggested that is applicable to 
all samples. The compound, [alpha],[alpha],[alpha],-trifluorotoluene, 
recommended as a surrogate spiking compound in Section 8.7 has been used 
successfully as an internal standard.
    7.4.1  Prepare calibration standards at a minimum of three 
concentration levels for each parameter of interest as described in 
Section 7.3.1.
    7.4.2  Prepare a spiking solution containing each of the internal 
standards using the procedures described in Sections 6.6 and 6.7. It is 
recommended that the secondary dilution standard be prepared at a 
concentration of 15 [mu]g/mL of each internal standard compound. The 
addition of 10 [mu]l of this

[[Page 48]]

standard to 5.0 mL of sample or calibration standard would be equivalent 
to 30 [mu]g/L.
    7.4.3  Analyze each calibration standard according to Section 10, 
adding 10 [mu]L of internal standard spiking solution directly to the 
syringe (Section 10.4). Tabulate peak height or area responses against 
concentration for each compound and internal standard, and calculate 
response factors (RF) for each compound using Equation 1.

 
                                                                   RF=      (As)(Cis)    (Ais)(Cs)
----------------------------------------------------------------------------------------------------------------
 

                                                              Equation 1

where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Cis=Concentration of the internal standard
Cs=Concentration of the parameter to be measured.

If the RF value over the working range is a constant (<10% RSD), the RF 
can be assumed to be invariant and the average RF can be used for 
calculations. Alternatively, the results can be used to plot a 
calibration curve of response ratios, As/Ais, vs. 
RF.
    7.5  The working calibration curve, calibration factor, or RF must 
be verified on each working day by the measurement of a QC check sample.
    7.5.1  Prepare the QC check sample as described in Section 8.2.2.
    7.5.2  Analyze the QC check sample according to Section 10.
    7.5.3  For each parameter, compare the response (Q) with the 
corresponding calibration acceptance criteria found in Table 2. If the 
responses for all parameters of interest fall within the designated 
ranges, analysis of actual samples can begin. If any individual Q falls 
outside the range, a new calibration curve, calibration factor, or RF 
must be prepared for that parameter according to Section 7.3 or 7.4.

                           8. Quality Control

    8.1 Each laboratory that uses this method is required to operate a 
formal quality control program. The mimimum requirements of this program 
consist of an initial demonstration of laboratory capability and an 
ongoing analysis of spiked samples to evaluate and document data 
quality. The laboratory must maintain records to document the quality of 
data that is generated. Ongoing data quality checks are compared with 
established performance criteria to determine if the results of analyses 
meet the performance characteristics of the method. When results of 
sample spikes indicate atypical method performance, a quality control 
check standard must be analyzed to confirm that the measurements were 
performed in an in-control mode of operation.
    8.1.1  The analyst must make an initial, one-time, demonstration of 
the ability to generate acceptable accuracy and precision with this 
method. This ability is established as described in Section 8.2.
    8.1.2  In recognition of advances that are occurring in 
chromatography, the analyst is permitted certain options (detailed in 
Section 10.1) to improve the separations or lower the cost of 
measurements. Each time such a modification is made to the method, the 
analyst is required to repeat the procedure in Section 8.2.
    8.1.3  Each day, the analyst must analyze a reagent water blank to 
demonstrate that interferences from the analytical system are under 
control.
    8.1.4  The laboratory must, on an ongoing basis, spike and analyze a 
minimum of 10% of all samples to monitor and evaluate laboratory data 
quality. This procedure is described in Section 8.3.
    8.1.5  The laboratory must, on an ongoing basis, demonstrate through 
the analyses of quality control check standards that the operation of 
the measurement system is in control. This procedure is described in 
Section 8.4. The frequency of the check standard analyses is equivalent 
to 10% of all samples analyzed but may be reduced if spike recoveries 
from samples (Section 8.3) meet all specified quality control criteria.
    8.1.6  The laboratory must maintain performance records to document 
the quality of data that is generated. This procedure is described in 
Section 8.5.
    8.2  To establish the ability to generate acceptable accuracy and 
precision, the analyst must perform the following operations.
    8.2.1  A quality control (QC) check sample concentrate is required 
containing each parameter of interest at a concentration of 10 [mu]g/mL 
in methanol. The QC check sample concentrate must be obtained from the 
U.S. Environmental Protection Agency, Environmental Monitoring and 
Support Laboratory in Cincinnati, Ohio, if available. If not available 
from that source, the QC check sample concentrate must be obtained from 
another external source. If not available from either source above, the 
QC check sample concentrate must be prepared by the laboratory using 
stock standards prepared independently from those used for calibration.
    8.2.2  Prepare a QC check sample to contain 20 [mu]g/L of each 
parameter by adding 200 [mu]L of QC check sample concentrate to 100 mL 
of reagant water.
    8.2.3  Analyze four 5-mL aliquots of the well-mixed QC check sample 
according to Section 10.
    8.2.4  Calculate the average recovery (X) in [mu]g/L, and the 
standard deviation of the recovery (s) in [mu]g/L, for each parameter of 
interest using the four results.
    8.2.5  For each parameter compare s and X with the corresponding 
acceptance criteria

[[Page 49]]

for precision and accuracy, respectively, found in Table 2. If s and X 
for all parameters of interest meet the acceptance criteria, the system 
performance is acceptable and analysis of actual samples can begin. If 
any individual s exceeds the precision limit or any individual X falls 
outside the range for accuracy, the system performance is unacceptable 
for that parameter.
    Note: The large number of parameters in Table 2 present a 
substantial probability that one or more will fail at least one of the 
acceptance criteria when all parameters are analyzed.
    8.2.6  When one or more of the parameters tested fail at least one 
of the acceptance criteria, the analyst must proceed according to 
Section 8.2.6.1 or 8.2.6.2.
    8.2.6.1  Locate and correct the source of the problem and repeat the 
test for all parameters of interest beginning with Section 8.2.3.
    8.2.6.2  Beginning with Section 8.2.3, repeat the test only for 
those parameters that failed to meet criteria. Repeated failure, 
however, will confirm a general problem with the measurement system. If 
this occurs, locate and correct the source of the problem and repeat the 
test for all compounds of interest beginning with Section 8.2.3.
    8.3  The laboratory must, on an ongoing basis, spike at least 10% of 
the samples from each sample site being monitored to assess accuracy. 
For laboratories analyzing one to ten samples per month, at least one 
spiked sample per month is required.
    8.3.1  The concentration of the spike in the sample should be 
determined as follows:
    8.3.1.1  If, as in compliance monitoring, the concentration of a 
specific parameter in the sample is being checked against a regulatory 
concentration limit, the spike should be at that limit or 1 to 5 times 
higher than the background concentration determined in Section 8.3.2, 
whichever concentration would be larger.
    8.3.1.2  If the concentration of a specific parameter in the sample 
is not being checked against a limit specific to that parameter, the 
spike should be at 20 [mu]g/L or 1 to 5 times higher than the background 
concentration determined in Section 8.3.2, whichever concentration would 
be larger.
    8.3.2  Analyze one 5-mL sample aliquot to determine the background 
concentration (B) of each parameter. If necessary, prepare a new QC 
check sample concentrate (Section 8.2.1) appropriate for the background 
concentrations in the sample. Spike a second 5-mL sample aliquot with 10 
[mu]L of the QC check sample concentrate and analyze it to determine the 
concentration after spiking (A) of each parameter. Calculate each 
percent recovery (P) as 100(A-B)%/T, where T is the known true value of 
the spike.
    8.3.3  Compare the percent recovery (P) for each parameter with the 
corresponding QC acceptance criteria found in Table 2. These acceptance 
criteria were calculated to include an allowance for error in 
measurement of both the background and spike concentrations, assuming a 
spike to background ratio of 5:1. This error will be accounted for to 
the extent that the analyst's spike to background ratio approaches 
5:1.7 If spiking was performed at a concentration lower than 
20 [mu]g/L, the analyst must use either the QC acceptance criteria in 
Table 2, or optional QC acceptance criteria calculated for the specific 
spike concentration. To calculate optional acceptance criteria for the 
recovery of a parameter: (1) Calculate accuracy (X') using the equation 
in Table 3, substituting the spike concentration (T) for C; (2) 
calculate overall precision (S') using the equation in Table 3, 
substituting X' for X; (3) calculate the range for recovery at the spike 
concentration as (100 X'/T)  2.44(100 S'/T)%.7
    8.3.4  If any individual P falls outside the designated range for 
recovery, that parameter has failed the acceptance criteria. A check 
standard containing each parameter that failed the criteria must be 
analyzed as described in Section 8.4.
    8.4  If any parameter fails the acceptance criteria for recovery in 
Section 8.3, a QC check standard containing each parameter that failed 
must be prepared and analyzed.
    Note: The frequency for the required analysis of a QC check standard 
will depend upon the number of parameters being simultaneously tested, 
the complexity of the sample matrix, and the performance of the 
laboratory.
    8.4.1  Prepare the QC check standard by adding 10 [mu]L of QC check 
sample concentrate (Section 8.2.1 or 8.3.2) to 5 mL of reagent water. 
The QC check standard needs only to contain the parameters that failed 
criteria in the test in Section 8.3.
    8.4.2  Analyze the QC check standard to determine the concentration 
measured (A) of each parameter. Calculate each percent recovery 
(Ps) as 100 (A/T)%, where T is the true value of the standard 
concentration.
    8.4.3  Compare the percent recovery (Ps) for each 
parameter with the corresponding QC acceptance criteria found in Table 
2. Only parameters that failed the test in Section 8.3 need to be 
compared with these criteria. If the recovery of any such parameter 
falls outside the designated range, the laboratory performance for that 
parameter is judged to be out of control, and the problem must be 
immediately identified and corrected. The analytical result for that 
parameter in the unspiked sample is suspect and may not be reported for 
regulatory compliance purposes.
    8.5  As part of the QC program for the laboratory, method accuracy 
for wastewater samples must be assessed and records must be maintained. 
After the analysis of five spiked wastewater samples as in Section 8.3, 
calculate the average percent recovery (P)

[[Page 50]]

and the standard deviation of the percent recovery (sp). 
Express the accuracy assessment as a percent recovery interval from P-
2sp to P+2sp. If P=90% and sp=10%, for 
example, the accuracy interval is expressed as 70-110%. Update the 
accuracy assessment for each parameter on a regular basis (e.g. after 
each five to ten new accuracy measurements).
    8.6  It is recommended that the laboratory adopt additional quality 
assurance practices for use with this method. The specific practices 
that are most productive depend upon the needs of the laboratory and the 
nature of the samples. Field duplicates may be analyzed to assess the 
precision of the environmental measurements. When doubt exists over the 
identification of a peak on the chromatogram, confirmatory techniques 
such as gas chromatography with a dissimilar column, specific element 
detector, or mass spectrometer must be used. Whenever possible, the 
laboratory should analyze standard reference materials and participate 
in relevant performance evaluation studies.
    8.7  The analyst should monitor both the performance of the 
analytical system and the effectiveness of the method in dealing with 
each sample matrix by spiking each sample, standard, and reagent water 
blank with surrogate compounds (e.g. [alpha], [alpha], [alpha],-
trifluorotoluene) that encompass the range of the temperature program 
used in this method. From stock standard solutions prepared as in 
Section 6.6, add a volume to give 750 [mu]g of each surrogate to 45 mL 
of reagent water contained in a 50-mL volumetric flask, mix and dilute 
to volume for a concentration of 15 mg/[mu]L. Add 10 [mu]L of this 
surrogate spiking solution directly into the 5-mL syringe with every 
sample and reference standard analyzed. Prepare a fresh surrogate 
spiking solution on a weekly basis. If the internal standard calibration 
procedure is being used, the surrogate compounds may be added directly 
to the internal standard spiking solution (Section 7.4.2).

            9. Sample Collection, Preservation, and Handling

    9.1  The samples must be iced or refrigerated from the time of 
collection until analysis. If the sample contains free or combined 
chlorine, add sodium thiosulfate preservative (10 mg/40 mL is sufficient 
for up to 5 ppm Cl2) to the empty sample bottle just prior to 
shipping to the sampling site. EPA Method 330.4 or 330.5 may be used for 
measurement of residual chlorine.8 Field test kits are 
available for this purpose.
    9.2  Collect about 500 mL of sample in a clean container. Adjust the 
pH of the sample to about 2 by adding 1+1 HCl while stirring. Fill the 
sample bottle in such a manner that no air bubbles pass through the 
sample as the bottle is being filled. Seal the bottle so that no air 
bubbles are entrapped in it. Maintain the hermetic seal on the sample 
bottle until time of analysis.
    9.3  All samples must be analyzed within 14 days of 
collection.3

                              10. Procedure

    10.1  Table 1 summarizes the recommended operating conditions for 
the gas chromatograph. Included in this table are estimated retention 
times and MDL that can be achieved under these conditions. An example of 
the separations achieved by Column 1 is shown in Figure 6. Other packed 
columns, chromatographic conditions, or detectors may be used if the 
requirements of Section 8.2 are met.
    10.2  Calibrate the system daily as described in Section 7.
    10.3  Adjust the purge gas (nitrogen or helium) flow rate to 40 mL/
min. Attach the trap inlet to the purging device, and set the purge and 
trap system to purge (Figure 3). Open the syringe valve located on the 
purging device sample introduction needle.
    10.4  Allow the sample to come to ambient temperature prior to 
introducing it to the syringe. Remove the plunger from a 5-mL syringe 
and attach a closed syringe valve. Open the sample bottle (or standard) 
and carefully pour the sample into the syringe barrel to just short of 
overflowing. Replace the syringe plunger and compress the sample. Open 
the syringe valve and vent any residual air while adjusting the sample 
volume to 5.0 mL. Since this process of taking an aliquot destroys the 
validity of the sample for future analysis, the analyst should fill a 
second syringe at this time to protect against possible loss of data. 
Add 10.0 [mu]L of the surrogate spiking solution (Section 8.7) and 10.0 
[mu]L of the internal standard spiking solution (Section 7.4.2), if 
applicable, through the valve bore, then close the valve.
    10.5  Attach the syringe-syringe valve assembly to the syringe valve 
on the purging device. Open the syringe valves and inject the sample 
into the purging chamber.
    10.6  Close both valves and purge the sample for 12.00.1 
min at ambient temperature.
    10.7  After the 12-min purge time, disconnect the purging device 
from the trap. Dry the trap by maintaining a flow of 40 mL/min of dry 
purge gas through it for 6 min (Figure 4). If the purging device has no 
provision for bypassing the purger for this step, a dry purger should be 
inserted into the device to minimize moisture in the gas. Attach the 
trap to the chromatograph, adjust the purge and trap system to the 
desorb mode (Figure 5), and begin to temperature program the gas 
chromatograph. Introduce the trapped materials to the GC column by 
rapidly heating the trap to 180  deg.C while backflushing the trap with 
an inert gas between 20 and 60 mL/min for 4 min. If rapid heating of the 
trap cannot be achieved, the GC column must be used as

[[Page 51]]

a secondary trap by cooling it to 30  deg.C (subambient temperature, if 
poor peak geometry and random retention time problems persist) instead 
of the initial program temperature of 50  deg.C.
    10.8  While the trap is being desorbed into the gas chromatograph 
column, empty the purging chamber using the sample introduction syringe. 
Wash the chamber with two 5-mL flushes of reagent water.
    10.9  After desorbing the sample for 4 min, recondition the trap by 
returning the purge and trap system to the purge mode. Wait 15 s, then 
close the syringe valve on the purging device to begin gas flow through 
the trap. The trap temperature should be maintained at 180  deg.C. After 
approximately 7 min, turn off the trap heater and open the syringe valve 
to stop the gas flow through the trap. When the trap is cool, the next 
sample can be analyzed.
    10.10  Identify the parameters in the sample by comparing the 
retention times of the peaks in the sample chromatogram with those of 
the peaks in standard chromatograms. The width of the retention time 
window used to make identifications should be based upon measurements of 
actual retention time variations of standards over the course of a day. 
Three times the standard deviation of a retention time for a compound 
can be used to calculate a suggested window size; however, the 
experience of the analyst should weigh heavily in the interpretation of 
chromatograms.
    10.11  If the response for a peak exceeds the working range of the 
system, prepare a dilution of the sample with reagent water from the 
aliquot in the second syringe and reanalyze.

                            11. Calculations

    11.1  Determine the concentration of individual compounds in the 
sample.
    11.1.1  If the external standard calibration procedure is used, 
calculate the concentration of the parameter being measured from the 
peak response using the calibration curve or calibration factor 
determined in Section 7.3.2.
    11.1.2  If the internal standard calibration procedure is used, 
calculate the concentration in the sample using the response factor (RF) 
determined in Section 7.4.3 and Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.096

    Equation 2
where:
As = Response for the parameter to be measured.
Ais = Response for the internal standard.
Cis = Concentration of the internal standard.

    11.2  Report results in [mu]g/L without correction for recovery 
data. All QC data obtained should be reported with the sample results.

                         12. Method Performance

    12.1  The method detection limit (MDL) is defined as the minimum 
concentration of a substance that can be measured and reported with 99% 
confidence that the value is above zero.1 The MDL 
concentrations listed in Table 1 were obtained using reagent 
water.9 Similar results were achieved using representative 
wastewaters. The MDL actually achieved in a given analysis will vary 
depending on instrument sensitivity and matrix effects.
    12.2  This method has been demonstrated to be applicable for the 
concentration range from the MDL to 100 X MDL.9 Direct 
aqueous injection techniques should be used to measure concentration 
levels above 1000 x MDL.
    12.3  This method was tested by 20 laboratories using reagent water, 
drinking water, surface water, and three industrial wastewaters spiked 
at six concentrations over the range 2.1 to 550 [mu]g/L.9 
Single operator precision, overall precision, and method accuracy were 
found to be directly related to the concentration of the parameter and 
essentially independent of the sample matrix. Linear equations to 
describe these relationships are presented in Table 3.

                               References

    1. 40 CFR part 136, appendix B.
    2. Lichtenberg, J.J. ``Determining Volatile Organics at Microgram-
per-Litre-Levels by Gas Chromatography,'' Journal American Water Works 
Association, 66, 739 (1974).
    3. Bellar, T.A., and Lichtenberg, J.J. ``Semi-Automated Headspace 
Analysis of Drinking Waters and Industrial Waters for Purgeable Volatile 
Organic Compounds,'' Proceedings of Symposium on Measurement of Organic 
Pollutants in Water and Wastewater. American Society for Testing and 
Materials, STP 686, C.E. Van Hall, editor, 1978.
    4. ``Carcinogens--Working with Carcinogens,'' Department of Health, 
Education, and Welfare, Public Health Service, Center for Disease 
Control, National Institute for Occupational Safety and Health. 
Publication No. 77-206, August 1977.
    5. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR 
part 1910), Occupational Safety and Health Administration, OSHA 2206 
(Revised, January 1976).
    6. ``Safety in Academic Chemistry Laboratories,'' American Chemical 
Society Publication, Committee on Safety, 3rd Edition, 1979.
    7. Provost, L.P., and Elder, R.S. ``Interpretation of Percent 
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44 
used in the equation in Section 8.3.3. is two times the value 1.22 
derived in this report.)

[[Page 52]]

    8.``Methods 330.4 (Titrimetric, DPD-FAS) and 330.5 
(Spectrophotometric, DPD) for Chlorine, Total Residual,'' Methods for 
Chemical Analysis of Water and Wastes, EPA-600/4-79-020, U.S. 
Environmental Protection Agency, Office of Research and Development, 
Environmental Monitoring and Support Laboratory, Cincinnati, Ohio 45268. 
March 1979.
    9. ``EPA Method Study 25, Method 602, Purgeable Aromatics,'' EPA 
600/4-84-042, National Technical Information Service, PB84-196682, 
Springfield, Virginia 22161, May 1984.

     Table 1--Chromatographic Conditions and Method Detection Limits
------------------------------------------------------------------------
                                         Retention time (min)    Method
                                        ---------------------- detection
               Parameter                                          limit
                                          Column 1   Column 2  ([mu]g/L)
------------------------------------------------------------------------
Benzene................................       3.33       2.75       0.2
Toluene................................       5.75       4.25       0.2
Ethylbenzene...........................       8.25       6.25       0.2
Chlorobenzene..........................       9.17       8.02       0.2
1,4-Dichlorobenzene....................      16.8       16.2        0.3
1,3-Dichlorobenzene....................      18.2       15.0        0.4
1,2-Dichlorobenzene....................      25.9       19.4        0.4
------------------------------------------------------------------------
Column 1 conditions: Supelcoport (100/120 mesh) coated with 5% SP-1200/
  1.75% Bentone-34 packed in a 6 ft x 0.085 in. ID stainless steel
  column with helium carrier gas at 36 mL/min flow rate. Column
  temperature held at 50  deg.C for 2 min then programmed at 6  deg.C/
  min to 90  deg.C for a final hold.
Column 2 conditions: Chromosorb W-AW (60/80 mesh) coated with 5% 1,2,3-
  Tris(2-cyanoethyoxy)propane packed in a 6 ft x 0.085 in. ID stainless
  steel column with helium carrier gas at 30 mL/min flow rate. Column
  temperature held at 40  deg.C for 2 min then programmed at 2  deg.C/
  min to 100  deg.C for a final hold.


                          Table 2--Calibration and QC Acceptance Criteria--Method 602 a
----------------------------------------------------------------------------------------------------------------
                                                                                  Limit
                                                                   Range for Q    for s   Range for X  Range for
                            Parameter                               ([mu]g/L)    ([mu]g/   ([mu]g/L)    P, Ps(%)
                                                                                   L)
----------------------------------------------------------------------------------------------------------------
Benzene..........................................................    15.4-24.6       4.1    10.0-27.9     39-150
Chlorobenzene....................................................    16.1-23.9       3.5    12.7-25.4     55-135
1,2-Dichlorobenzene..............................................    13.6-26.4       5.8    10.6-27.6     37-154
1,3-Dichlorobenzene..............................................    14.5-25.5       5.0    12.8-25.5     50-141
1,4-Dichlorobenzene..............................................    13.9-26.1       5.5    11.6-25.5     42-143
Ethylbenzene.....................................................    12.6-27.4       6.7    10.0-28.2     32-160
Toluene..........................................................    15.5-24.5       4.0    11.2-27.7     46-148
----------------------------------------------------------------------------------------------------------------
Q=Concentration measured in QC check sample, in [mu]g/L (Section 7.5.3).
s=Standard deviation of four recovery measurements, in [mu]g/L (Section 8.2.4).
X=Average recovery for four recovery measurements, in [mu]g/L (Section 8.2.4).
Ps, P=Percent recovery measured (Section 8.3.2, Section 8.4.2).
a Criteria were calculated assuming a QC check sample concentration of 20 [mu]g/L.
 
 Note: These criteria are based directly upon the method performance data in Table 3. Where necessary, the
  limits for recovery have been broadened to assure applicability of the limits to concentrations below those
  used to develop Table 3.


                Table 3--Method Accuracy and Precision as Functions of Concentration--Method 602
----------------------------------------------------------------------------------------------------------------
                                                                   Accuracy, as   Single analyst      Overall
                            Parameter                              recovery, X'    precision, s'   precision, S'
                                                                     ([mu]g/L)       ([mu]g/L)       ([mu]g/L)
----------------------------------------------------------------------------------------------------------------
Benzene.........................................................      0.92C+0.57      0.09X+0.59      0.21X+0.56
Chlorobenzene...................................................      0.95C+0.02      0.09X+0.23      0.17X+0.10
1,2-Dichlorobenzene.............................................      0.93C+0.52      0.17X-0.04      0.22X+0.53
1,3-Dichlorobenzene.............................................      0.96C-0.05      0.15X-0.10      0.19X+0.09
1,4-Dichlorobenzene.............................................      0.93C-0.09      0.15X+0.28      0.20X+0.41
Ethylbenzene....................................................      0.94C+0.31      0.17X+0.46      0.26X+0.23
Toluene.........................................................      0.94C+0.65      0.09X+0.48      0.18X+0.71
----------------------------------------------------------------------------------------------------------------
X'=Expected recovery for one or more measurements of a sample containing a concentration of C, in [mu]g/L.
S'=Expected single analyst standard deviation of measurements at an average concentration found of X, in X [mu]g/
  L.
S'=Expected interlaboratory standard deviation of measurements at an average concentration found of X, in [mu]g/
  L.
C=True value for the Concentration, in [mu]g/L.
X=Average recovery found for measurements of samples containing a concentration of C, in [mu]g/L.


[[Page 53]]

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[[Page 57]]

                 Method 603--Acrolein and Acrylonitrile

                        1. Scope and Application

    1.1  This method covers the determination of acrolein and 
acrylonitrile. The following parameters may be determined by this 
method:

------------------------------------------------------------------------
                                                    STORET
                    Parameter                         No.      CAS No.
------------------------------------------------------------------------
Acrolein.........................................     34210     107-02-8
Acrylonitrile....................................     34215     107-13-1
------------------------------------------------------------------------
 

    1.2  This is a purge and trap gas chromatographic (GC) method 
applicable to the determination of the compounds listed above in 
municipal and industrial discharges as provided under 40 CFR 136.1. When 
this method is used to analyze unfamiliar samples for either or both of 
the compounds above, compound identifications should be supported by at 
least one additional qualitative technique. This method describes 
analytical conditions for a second gas chromatographic column that can 
be used to confirm measurements made with the primary column. Method 624 
provides gas chromatograph/mass spectrometer (GC/MS) conditions 
appropriate for the qualitative and quantitative confirmation of results 
for the parameters listed above, if used with the purge and trap 
conditions described in this method.
    1.3  The method detection limit (MDL, defined in Section 12.1) 
1 for each parameter is listed in Table 1. The MDL for a 
specific wastewater may differ from those listed, depending upon the 
nature of interferences in the sample matrix.
    1.4  Any modification of this method, beyond those expressly 
permitted, shall be considered as a major modification subject to 
application and approval of alternate test procedures under 40 CFR 136.4 
and 136.5.
    1.5  This method is restricted to use by or under the supervision of 
analysts experienced in the operation of a purge and trap system and a 
gas chromatograph and in the interpretation of gas chromatograms. Each 
analyst must demonstrate the ability to generate acceptable results with 
this method using the procedure described in Section 8.2.

                          2. Summary of Method

    2.1  An inert gas is bubbled through a 5-mL water sample contained 
in a heated purging chamber. Acrolein and acrylonitrile are transferred 
from the aqueous phase to the vapor phase. The vapor is swept through a 
sorbent trap where the analytes are trapped. After the purge is 
completed, the trap is heated and backflushed with the inert gas to 
desorb the compound onto a gas chromatographic column. The gas 
chromatograph is temperature programmed to separate the analytes which 
are then detected with a flame ionization detector.2, 3
    2.2  The method provides an optional gas chromatographic column that 
may be helpful in resolving the compounds of interest from the 
interferences that may occur.

                            3. Interferences

    3.1  Impurities in the purge gas and organic compound outgassing 
from the plumbing of the trap account for the majority of contamination 
problems. The analytical system must be demonstrated to be free from 
contamination under the conditions of the analysis by running laboratory 
reagent blanks as described in Section 8.1.3. The use of non-Teflon 
plastic tubing, non-Teflon thread sealants, or flow controllers with 
rubber components in the purge and trap system should be avoided.
    3.2  Samples can be contaminated by diffusion of volatile organics 
through the septum seal into the sample during shipment and storage. A 
field reagent blank prepared from reagent water and carried through the 
sampling and handling protocol can serve as a check on such 
contamination.
    3.3  Contamination by carry-over can occur whenever high level and 
low level samples are sequentially analyzed. To reduce carry-over, the 
purging device and sample syringe must be rinsed between samples with 
reagent water. Whenever an unusually concentrated sample is encountered, 
it should be followed by an analysis of reagent water to check for cross 
contamination. For samples containing large amounts of water-soluble 
materials, suspended solids, high boiling compounds or high analyte 
levels, it may be necessary to wash the purging device with a detergent 
solution, rinse it with distilled water, and then dry it in an oven at 
105  deg.C between analyses. The trap and other parts of the system are 
also subject to contamination, therefore, frequent bakeout and purging 
of the entire system may be required.

                                4. Safety

    4.1  The toxicity or carcinogenicity of each reagent used in this 
method has not been precisely defined; however, each chemical compound 
should be treated as a potential health hazard. From this view point, 
exposure to these chemicals must be reduced to the lowest possible level 
by whatever means available. The laboratory is responsible for 
maintaining a current awareness file of OSHA regulations regarding the 
safe handling of the chemicals specified in this method. A reference 
file of material data handling sheets should also be made available to 
all personnel involved in the chemical analysis. Additional references 
to laboratory safety are available and have been identified 
4, 6 for the information of the analyst.

[[Page 58]]

                       5. Apparatus and Materials

    5.1  Sampling equipment, for discrete sampling.
    5.1.1  Vial--25-mL capacity or larger, equipped with a screw cap 
with a hole in the center (Pierce 13075 or equivalent). 
Detergent wash, rinse with tap and distilled water, and dry at 105 
deg.C before use.
    5.1.2  Septum--Teflon-faced silicone (Pierce 12722 or 
equivalent). Detergent wash, rinse with tap and distilled water and dry 
at 105  deg.C for 1 h before use.
    5.2  Purge and trap system--The purge and trap system consists of 
three separate pieces of equipment: a purging device, trap, and 
desorber. Several complete systems are now commercially available.
    5.2.1  The purging device must be designed to accept 5-mL, samples 
with a water column at least 3 cm deep. The gaseous head space between 
the water column and the trap must have a total volume of less than 15 
mL. The purge gas must pass through the water column as finely divided 
bubbles with a diameter of less than 3 mm at the origin. The purge gas 
must be introduced no more than 5 mm from the base of the water column. 
The purging device must be capable of being heated to 85  deg.C within 
3.0 min after transfer of the sample to the purging device and being 
held at 85 2  deg.C during the purge cycle. The entire water 
column in the purging device must be heated. Design of this modification 
to the standard purging device is optional, however, use of a water bath 
is suggested.
    5.2.1.1  Heating mantle--To be used to heat water bath.
    5.2.1.2  Temperature controller--Equipped with thermocouple/sensor 
to accurately control water bath temperature to 2  deg.C. 
The purging device illustrated in Figure 1 meets these design criteria.
    5.2.2  The trap must be at least 25 cm long and have an inside 
diameter of at least 0.105 in. The trap must be packed to contain 1.0 cm 
of methyl silicone coated packing (Section 6.5.2) and 23 cm of 2,6-
diphenylene oxide polymer (Section 6.5.1). The minimum specifications 
for the trap are illustrated in Figure 2.
    5.2.3  The desorber must be capable of rapidly heating the trap to 
180  deg.C, The desorber illustrated in Figure 2 meets these design 
criteria.
    5.2.4  The purge and trap system may be assembled as a separate unit 
as illustrated in Figure 3 or be coupled to a gas chromatograph.
    5.3  pH paper--Narrow pH range, about 3.5 to 5.5 (Fisher Scientific 
Short Range Alkacid No. 2, 14-837-2 or equivalent).
    5.4  Gas chromatograph--An analytical system complete with a 
temperature programmable gas chromatograph suitable for on-column 
injection and all required accessories including syringes, analytical 
columns, gases, detector, and strip-chart recorder. A data system is 
recommended for measuring peak areas.
    5.4.1  Column 1--10 ft long x 2 mm ID glass or stainless steel, 
packed with Porapak-QS (80/100 mesh) or equivalent. This column was used 
to develop the method performance statements in Section 12. Guidelines 
for the use of alternate column packings are provided in Section 10.1.
    5.4.2  Column 2--6 ft long x 0.1 in. ID glass or stainless steel, 
packed with Chromosorb 101 (60/80 mesh) or equivalent.
    5.4.3  Detector--Flame ionization detector. This type of detector 
has proven effective in the analysis of wastewaters for the parameters 
listed in the scope (Section 1.1), and was used to develop the method 
performance statements in Section 12. Guidelines for the use of 
alternate detectors are provided in Section 10.1.
    5.5  Syringes--5-mL, glass hypodermic with Luerlok tip (two each).
    5.6  Micro syringes--25-[mu]L, 0.006 in. ID needle.
    5.7  Syringe valve--2-way, with Luer ends (three each).
    5.8  Bottle--15-mL, screw-cap, with Teflon cap liner.
    5.9  Balance--Analytical, capable of accurately weighing 0.0001 g.

                               6. Reagents

    6.1  Reagent water--Reagent water is defined as a water in which an 
interferent is not observed at the MDL of the parameters of interest.
    6.1.1  Reagent water can be generated by passing tap water through a 
carbon filter bed containing about 1 lb of activated carbon (Filtrasorb-
300, Calgon Corp., or equivalent).
    6.1.2  A water purification system (Millipore Super-Q or equivalent) 
may be used to generate reagent water.
    6.1.3  Regent water may also be prepared by boiling water for 15 
min. Subsequently, while maintaining the temperature at 90  deg.C, 
bubble a contaminant-free inert gas through the water for 1 h. While 
still hot, transfer the water to a narrow mouth screw-cap bottle and 
seal with a Teflon-lined septum and cap.
    6.2  Sodium thiosulfate--(ACS) Granular.
    6.3  Sodium hydroxide solution (10 N)--Dissolve 40 g of NaOH (ACS) 
in reagent water and dilute to 100 mL.
    6.4  Hydrochloric acid (1+1)--Slowly, add 50 mL of concentrated HCl 
(ACS) to 50 mL of reagent water.
    6.5  Trap Materials:
    6.5.1  2,6-Diphenylene oxide polymer--Tenax (60/80 mesh), 
chromatographic grade or equivalent.
    6.5.2  Methyl silicone packing--3% OV-1 on Chromosorb-W (60/80 mesh) 
or equivalent.

[[Page 59]]

    6.6  Stock standard solutions--Stock standard solutions may be 
prepared from pure standard materials or purchased as certified 
solutions. Prepare stock standard solutions in reagent water using 
assayed liquids. Since acrolein and acrylonitrile are lachrymators, 
primary dilutions of these compounds should be prepared in a hood. A 
NIOSH/MESA approved toxic gas respirator should be used when the analyst 
handles high concentrations of such materials.
    6.6.1  Place about 9.8 mL of reagent water into a 10-mL ground glass 
stoppered volumetric flask. For acrolein standards the reagent water 
must be adjusted to pH 4 to 5. Weight the flask to the nearest 0.1 mg.
    6.6.2  Using a 100-[mu]L syringe, immediately add two or more drops 
of assayed reference material to the flask, then reweigh. Be sure that 
the drops fall directly into the water without contacting the neck of 
the flask.
    6.6.3  Reweigh, dilute to volume, stopper, then mix by inverting the 
flask several times. Calculate the concentration in [mu]g/[mu]L from the 
net gain in weight. When compound purity is assayed to be 96% or 
greater, the weight can be used without correction to calculate the 
concentration of the stock staldard. Optionally, stock standard 
solutions may be prepared using the pure standard material by 
volumetrically measuring the appropriate amounts and determining the 
weight of the material using the density of the material. Commercially 
prepared stock standards may be used at any concentration if they are 
certified by the manufactaurer or by an independent source.
    6.6.4  Transfer the stock standard solution into a Teflon-sealed 
screw-cap bottle. Store at 4  deg.C and protect from light.
    6.6.5  Prepare fresh standards daily.
    6.7  Secondary dilution standards--Using stock standard solutions, 
prepare secondary dilution standards in reagent water that contain the 
compounds of interest, either singly or mixed together. The secondary 
dilution standards should be prepared at concentrations such that the 
aqueous calibration standards prepared in Section 7.3.1 or 7.4.1 will 
bracket the working range of the analytical system. Secondary dilution 
standards should be prepared daily and stored at 4  deg.C.
    6.8  Quality control check sample concentrate--See Section 8.2.1.

                             7. Calibration

    7.1  Assemble a purge and trap system that meets the specifications 
in Section 5.2. Condition the trap overnight at 180  deg.C by 
backflushing with an inert gas flow of at least 20 mL/min. Condition the 
trap for 10 min once daily prior to use.
    7.2  Connect the purge and trap system to a gas chromatograph. The 
gas chromatograph must be operated using temperature and flow rate 
conditions equivalent to those given in Table 1. Calibrate the purge and 
trap-gas chromatographic system using either the external standard 
technique (Section 7.3) or the internal standard technique (Section 
7.4).
    7.3  External standard calibration procedure:
    7.3.1  Prepare calibration standards at a minimum of three 
concentration levels for each parameter by carefully adding 20.0 [mu]L 
of one or more secondary dilution standards to 100, 500, or 1000 mL of 
reagent water. A 25-[mu]L syringe with a 0.006 in. ID needle should be 
used for this operation. One of the external standards should be at a 
concentration near, but above, the MDL and the other concentrations 
should correspond to the expected range of concentrations found in real 
samples or should define the working range of the detector. These 
standards must be prepared fresh daily.
    7.3.2  Analyze each calibration standard according to Section 10, 
and tabulate peak height or area responses versus the concentration of 
the standard. The results can be used to prepare a calibration curve for 
each compound. Alternatively, if the ratio of response to concentration 
(calibration factor) is a constant over the working range (< 10% 
relative standard deviation, RSD), linearity through the origin can be 
assumed and the average ratio or calibration factor can be used in place 
of a calibration curve.
    7.4  Internal standard calibration procedure--To use this approach, 
the analyst must select one or more internal standards that are similar 
in analytical behavior to the compounds of interest. The analyst must 
further demonstrate that the measurement of the internal standard is not 
affected by method or matrix interferences. Because of these 
limitations, no internal standard can be suggested that is applicable to 
all samples.
    7.4.1  Prepare calibration standards at a minimum of three 
concentration levels for each parameter of interest as described in 
Section 7.3.1.
    7.4.2  Prepare a spiking solution containing each of the internal 
standards using the procedures described in Sections 6.6 and 6.7. It is 
recommended that the secondary dilution standard be prepared at a 
concentration of 15 [mu]g/mL of each internal standard compound. The 
addition of 10 [mu]L of this standard to 5.0 mL of sample or calibration 
standard would be equivalent to 30 [mu]g/L.
    7.4.3  Analyze each calibration standard according to Section 10, 
adding 10 [mu]L of internal standard spiking solution directly to the 
syringe (Section 10.4). Tabulate peak height or area responses against 
concentration for each compound and internal standard, and calculate 
response factors (RF) for each compound using Equation 1.

[[Page 60]]



 
                                                                   RF=      (As)(Cis)    (Ais)(Cs)
----------------------------------------------------------------------------------------------------------------
 
 

                                                              Equation 1

where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Cis=Concentration of the internal standard.
Cs=Concentration of the parameter to be measured.

If the RF value over the working range is a constant (<10% RSD), the RF 
can be assumed to be invariant and the average RF can be used for 
calculations. Alternatively, the results can be used to plot a 
calibration curve of response ratios, As/Ais, vs. 
RF.
    7.5  The working calibration curve, calibration factor, or RF must 
be verified on each working day by the measurement of a QC check sample.
    7.5.1  Prepare the QC check sample as described in Section 8.2.2.
    7.5.2  Analyze the QC check sample according to Section 10.
    7.5.3  For each parameter, compare the response (Q) with the 
corresponding calibration acceptance criteria found in Table 2. If the 
responses for all parameters of interest fall within the designated 
ranges, analysis of actual samples can begin. If any individual Q falls 
outside the range, a new calibration curve, calibration factor, or RF 
must be prepared for that parameter according to Section 7.3 or 7.4.

                           8. Quality Control

    8.1  Each laboratory that uses this method is required to operate a 
formal quality control program. The minimum requirements of this program 
consist of an initial demonstration of laboratory capability and an 
ongoing analysis of spiked samples to evaluate and document data 
quality. The laboratory must maintain records to document the quality of 
data that is generated. Ongoing data quality checks are compared with 
established performance criteria to determine if the results of analyses 
meet the performance characteristics of the method. When results of 
sample spikes indicate atypical method performance, a quality control 
check standard must be analyzed to confirm that the measurements were 
performed in an in-control mode of operation.
    8.1.1  The analyst must make an initial, one-time, demonstration of 
the ability to generate acceptable accuracy and precision with this 
method. This ability is established as described in Section 8.2.
    8.1.2  In recognition of advances that are occurring in 
chromatography, the analyst is permitted certain options (detailed in 
Section 10.1) to improve the separations or lower the cost of 
measurements. Each time such a modification is made to the method, the 
analyst is required to repeat the procedure in Section 8.2.
    8.1.3  Each day, the analyst must analyze a reagent water blank to 
demonstrate that interferences from the analytical system are under 
control.
    8.1.4  The laboratory must, on an ongoing basis, spike and analyze a 
minimum of 10% of all samples to monitor and evaluate laboratory data 
quality. This procedure is described in Section 8.3.
    8.1.5  The laboratory must, on an ongoing basis, demonstrate through 
the analyses of quality control check standards that the operation of 
the measurement system is in control. This procedure is described in 
Section 8.4. The frequency of the check standard analyses is equivalent 
to 10% of all samples analyzed but may be reduced if spike recoveries 
from samples (Section 8.3) meet all specified quality control criteria.
    8.1.6  The laboratory must maintain performance records to document 
the quality of data that is generated. This procedure is described in 
Section 8.5.
    8.2  To establish the ability to generate acceptable accuracy and 
precision, the analyst must perform the following operations.
    8.2.1  A quality control (QC) check sample concentrate is required 
containing each parameter of interest at a concentration of 25 [mu]g/mL 
in reagent water. The QC check sample concentrate must be obtained from 
the U.S. Environmental Protection Agency, Environmental Monitoring and 
Support Laboratory in Cincinnati, Ohio, if available. If not available 
from that source, the QC check sample concentrate must be obtained from 
another external source. If not available from either source above, the 
QC check sample concentrate must be prepared by the laboratory using 
stock standards prepared independently from those used for calibration.
    8.2.2  Prepare a QC check sample to contain 50 [mu]g/L of each 
parameter by adding 200 [mu]L of QC check sample concentrate to 100 mL 
of reagent water.
    8.2.3  Analyze four 5-mL aliquots of the well-mixed QC check sample 
according to Section 10.
    8.2.4  Calculate the average recovery (X) in [mu]g/L, and the 
standard deviation of the recovery (s) in [mu]g/L, for each parameter 
using the four results.
    8.2.5  For each parameter compare s and X with the corresponding 
acceptance criteria for precision and accuracy, respectively, found in 
Table 3. If s and X for all parameters of interest meet the acceptance 
criteria, the system performance is acceptable and analysis of actual 
samples can begin. If either s exceeds the precision limit or X falls 
outside the range for accuracy, the system performance is unacceptable 
for that parameter. Locate and correct the source of the

[[Page 61]]

problem and repeat the test for each compound of interest.
    8.3  The laboratory must, on an ongoing basis, spike at least 10% of 
the samples from each sample site being monitored to assess accuracy. 
For laboratories analyzing one to ten samples per month, at least one 
spiked sample per month is required.
    8.3.1  The concentration of the spike in the sample should be 
determined as follows:
    8.3.1.1  If, as in compliance monitoring, the concentration of a 
specific parameter in the sample is being checked against a regulatory 
concentration limit, the spike should be at that limit or 1 to 5 times 
higher than the background concentration determined in Section 8.3.2, 
whichever concentration would be larger.
    8.3.1.2  If the concentration of a specific parameter in the sample 
is not being checked against a limit specific to that parameter, the 
spike should be at 50 [mu]g/L or 1 to 5 times higher than the background 
concentration determined in Section 8.3.2, whichever concentration would 
be larger.
    8.3.2  Analyze one 5-mL sample aliquot to determine the background 
concentration (B) of each parameter. If necessary, prepare a new QC 
check sample concentrate (Section 8.2.1) appropriate for the background 
concentrations in the sample. Spike a second 5-mL sample aliquot with 10 
[mu]L of the QC check sample concentrate and analyze it to determine the 
concentration after spiking (A) of each parameter. Calculate each 
percent recovery (P) as 100(A-B)%/T, where T is the known true value of 
the spike.
    8.3.3  Compare the percent recovery (P) for each parameter with the 
corresponding QC acceptance criteria found in Table 3. These acceptance 
criteria were calculated to include an allowance for error in 
measurement of both the background and spike concentrations, assuming a 
spike to background ratio of 5:1. This error will be accounted for to 
the extent that the analyst's spike to background ratio approaches 
5:1.7
    8.3.4  If any individual P falls outside the designated range for 
recovery, that parameter has failed the acceptance criteria. A check 
standard containing each parameter that failed the criteria must be 
analyzed as described in Section 8.4.
    8.4  If any parameter fails the acceptance criteria for recovery in 
Section 8.3, a QC check standard containing each parameter that failed 
must be prepared and analyzed.
    Note: The frequency for the required analysis of a QC check standard 
will depend upon the number of parameters being simultaneously tested, 
the complexity of the sample matrix, and the performance of the 
laboratory.
    8.4.1  Prepare the QC check standard by adding 10 [mu]L of QC check 
sample concentrate (Section 8.2.1 or 8.3.2) to 5 mL of reagent water. 
The QC check standard needs only to contain the parameters that failed 
criteria in the test in Section 8.3.
    8.4.2  Analyze the QC check standard to determine the concentration 
measured (A) of each parameter. Calculate each percent recovery 
(Ps) as 100 (A/T)%, where T is the true value of the standard 
concentration.
    8.4.3  Compare the percent recovery (Ps) for each 
parameter with the corresponding QC acceptance criteria found in Table 
3. Only parameters that failed the test in Section 8.3 need to be 
compared with these criteria. If the recovery of any such parameter 
falls outside the designated range, the laboratory performance for that 
parameter is judged to be out of control, and the problem must be 
immediately identified and corrected. The analytical result for that 
parameter in the unspiked sample is suspect and may not be reported for 
regulatory compliance purposes.
    8.5  As part of the QC program for the laboratory, method accuracy 
for wastewater samples must be assessed and records must be maintained. 
After the analysis of five spiked wastewater samples as in Section 8.3, 
calculate the average percent recovery (P) and the standard deviation of 
the percent recovery (sp). Express the accuracy assessment as 
a percent recovery interval from P-2sp to P+2sp. 
If P=90% and sp=10%, for example, the accuracy interval is 
expressed as 70-110%. Update the accuracy assessment for each parameter 
on a regular basis (e.g. after each five to ten new accuracy 
measurements).
    8.6  It is recommended that the laboratory adopt additional quality 
assurance practices for use with this method. The specific practices 
that are most productive depend upon the needs of the laboratory and the 
nature of the samples. Field duplicates may be analyzed to assess the 
precision of the environmental measurements. When doubt exists over the 
identification of a peak on the chromatogram, confirmatory techniques 
such as gas chromatography with a dissimilar column or mass spectrometer 
must be used. Whenever possible, the laboratory should analyze standard 
reference materials and participate in relevant performance evaluation 
studies.

            9. Sample Collection, Preservation, and Handling

    9.1  All samples must be iced or refrigerated from the time of 
collection until analysis. If the sample contains free or combined 
chlorine, add sodium thiosulfate preservative (10 mg/40 mL is sufficient 
for up to 5 ppm Cl2) to the empty sample bottle just prior to 
shipping to the sampling site. EPA Methods 330.4 and 330.5 may be used 
for measurement of residual chlorine.8 Field test kits are 
available for this purpose.
    9.2  If acrolein is to be analyzed, collect about 500 mL of sample 
in a clean glass container. Adjust the pH of the sample to 4 to 5 using 
acid or base, measuring with narrow

[[Page 62]]

range pH paper. Samples for acrolein analysis receiving no pH adjustment 
must be analyzed within 3 days of sampling.
    9.3  Grab samples must be collected in glass containers having a 
total volume of at least 25 mL. Fill the sample bottle just to 
overflowing in such a manner that no air bubbles pass through the sample 
as the bottle is being filled. Seal the bottle so that no air bubbles 
are entrapped in it. If preservative has been added, shake vigorously 
for 1 min. Maintain the hermetic seal on the sample bottle until time of 
analysis.
    9.4  All samples must be analyzed within 14 days of 
collection.3

                              10. Procedure

    10.1  Table 1 summarizes the recommended operating conditions for 
the gas chromatograph. Included in this table are estimated retention 
times and MDL that can be achieved under these conditions. An example of 
the separations achieved by Column 1 is shown in Figure 5. Other packed 
columns, chromatographic conditions, or detectors may be used if the 
requirements of Section 8.2 are met.
    10.2  Calibrate the system daily as described in Section 7.
    10.3  Adjust the purge gas (nitrogen or helium) flow rate to 20 mL-
min. Attach the trap inlet to the purging device, and set the purge and 
trap system to purge (Figure 3). Open the syringe valve located on the 
purging device sample introduction needle.
    10.4  Remove the plunger from a 5-mL syringe and attach a closed 
syringe valve. Open the sample bottle (or standard) and carefully pour 
the sample into the syringe barrel to just short of overflowing. Replace 
the syringe plunger and compress the sample. Open the syringe valve and 
vent any residual air while adjusting the sample volume to 5.0 mL. Since 
this process of taking an aliquot destroys the validity of the sample 
for future analysis, the analyst should fill a second syringe at this 
time to protect against possible loss of data. Add 10.0 [mu]L of the 
internal standard spiking solution (Section 7.4.2), if applicable, 
through the valve bore then close the valve.
    10.5  Attach the syringe-syringe valve assembly to the syringe valve 
on the purging device. Open the syringe valves and inject the sample 
into the purging chamber.
    10.6  Close both valves and purge the sample for 15.0  
0.1 min while heating at 85  2  deg.C.
    10.7  After the 15-min purge time, attach the trap to the 
chromatograph, adjust the purge and trap system to the desorb mode 
(Figure 4), and begin to temperature program the gas chromatograph. 
Introduce the trapped materials to the GC column by rapidly heating the 
trap to 180  deg.C while backflushing the trap with an inert gas between 
20 and 60 mL/min for 1.5 min.
    10.8  While the trap is being desorbed into the gas chromatograph, 
empty the purging chamber using the sample introduction syringe. Wash 
the chamber with two 5-mL flushes of reagent water.
    10.9  After desorbing the sample for 1.5 min, recondition the trap 
by returning the purge and trap system to the purge mode. Wait 15 s then 
close the syringe valve on the purging device to begin gas flow through 
the trap. The trap temperature should be maintained at 210  deg.C. After 
approximately 7 min, turn off the trap heater and open the syringe valve 
to stop the gas flow through the trap. When the trap is cool, the next 
sample can be analyzed.
    10.10  Identify the parameters in the sample by comparing the 
retention times of the peaks in the sample chromatogram with those of 
the peaks in standard chromatograms. The width of the retention time 
window used to make identifications should be based upon measurements of 
actual retention time variations of standards over the course of a day. 
Three times the standard deviation of a retention time for a compound 
can be used to calculate a suggested window size; however, the 
experience of the analyst should weigh heavily in the interpretation of 
chromatograms.

                            11. Calculations

    11.1  Determine the concentration of individual compounds in the 
sample.
    11.1.1  If the external standard calibration procedure is used, 
calculate the concentration of the parameter being measured from the 
peak response using the calibration curve or calibration factor 
determined in Section 7.3.2.
    11.1.2  If the internal standard calibration procedure is used, 
calculate the concentration in the sample using the response factor (RF) 
determined in Section 7.4.3 and Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.097

                                                              Equation 2

where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Cis=Concentration of the internal standard.

    11.2  Report results in [mu]g/L without correction for recovery 
data. All QC data obtained should be reported with the sample results.

                         12. Method Performance

    12.1  The method detection limit (MDL) is defined as the minimum 
concentration of a substance that can be measured and reported with 99% 
confidence that the value is above

[[Page 63]]

zero.1 The MDL concentrations listed in Table 1 were obtained 
using reagent water.9 The MDL actually achieved in a given 
analysis will vary depending on instrument sensitivity and matrix 
effects.
    12.2  This method is recommended for the concentration range from 
the MDL to 1,000xMDL. Direct aqueous injection techniques should be used 
to measure concentration levels above 1,000xMDL.
    12.3  In a single laboratory (Battelle-Columbus), the average 
recoveries and standard deviations presented in Table 2 were 
obtained.9 Seven replicate samples were analyzed at each 
spike level.

                               References

    1. 40 CFR part 136, appendix B.
    2. Bellar, T.A., and Lichtenberg, J.J. ``Determining Volatile 
Organics at Microgram-per-Litre-Levels by Gas Chromatography,'' Journal 
American Water Works Association, 66, 739 (1974).
    3. ``Evaluate Test Procedures for Acrolein and Acrylonitrile,'' 
Special letter report for EPA Project 4719-A, U.S. Environmental 
Protection Agency, Environmental Monitoring and Support Laboratory, 
Cincinnati, Ohio 45268, 27 June 1979.
    4. ``Carcinogens--Working With Carcinogens,'' Department of Health, 
Education, and Welfare, Public Health Service, Center for Disease 
Control, National Institute for Occupational Safety and Health, 
Publication No. 77-206, August 1977.
    5. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR 
part 1910), Occupational Safety and Health Administration, OSHA 2206 
(Revised, January 1976).
    6. ``Safety in Academic Chemistry Laboratories,'' American Chemical 
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
    7. Provost, L.P., and Elder, R.S. ``Interpretation of Percent 
Recovery Data,'' American Laboratory, 15, 58-63 (1983).
    8. ``Methods 330.4 (Titrimetric, DPD-FAS) and 330.5 
(Spectrophotometric, DPD) for Chlorine, Total Residual,'' Methods for 
Chemical Analysis of Water and Wastes, EPA-600/4-79-020, U.S. 
Environmental Protection Agency, Environmental Monitoring and Support 
Laboratory, Cincinnati, Ohio 45268, March 1979.
    9. ``Evaluation of Method 603 (Modified),'' EPA-600/4-84-ABC, 
National Technical Information Service, PB84-, Springfield, Virginia 
22161, Nov. 1984.

     Table 1--Chromatographic Conditions and Method Detection Limits
------------------------------------------------------------------------
                                       Retention time (min)     Method
                                     ------------------------  detection
              Parameter                                          limit
                                       Column 1    Column 2    ([mu]g/L)
------------------------------------------------------------------------
Acrolein............................     10.6         8.2         0.7
Acrylonitrile.......................     12.7         9.8         0.5
------------------------------------------------------------------------
Column 1 conditions: Porapak-QS (80/100 mesh) packed in a 10 ft x 2 mm
  ID glass or stainless steel column with helium carrier gas at 30 mL/
  min flow rate. Column temperature held isothermal at 110  deg.C for
  1.5 min (during desorption), then heated as rapidly as possible to 150
   deg.C and held for 20 min; column bakeout at 190  deg.C for 10
  min.\9\
Column 2 conditions: Chromosorb 101 (60/80 mesh) packed in a 6 ft. x 0.1
  in. ID glass or stainless steel column with helium carrier gas at 40
  mL/min flow rate. Column temperature held isothermal at 80  deg.C for
  4 min, then programmed at 50  deg.C/min to 120  deg.C and held for 12
  min.


                          Table 2--Single Laboratory Accuracy and Precision--Method 603
----------------------------------------------------------------------------------------------------------------
                                                                         Spike
                                                              Sample     conc.    Average    Standard   Average
                         Parameter                            matrix    ([mu]g/   recovery  deviation   percent
                                                                          L)     ([mu]g/L)  ([mu]g/L)   recovery
----------------------------------------------------------------------------------------------------------------
Acrolein...................................................        RW       5.0        5.2        0.2        104
                                                                   RW      50.0       51.4        0.7        103
                                                                 POTW       5.0        4.0        0.2         80
                                                                 POTW      50.0       44.4        0.8         89
                                                                   IW       5.0        0.1        0.1          2
                                                                   IW     100.0        9.3        1.1          9
Acrylonitrile..............................................        RW       5.0        4.2        0.2         84
                                                                   RW      50.0       51.4        1.5        103
                                                                 POTW      20.0       20.1        0.8        100
                                                                 POTW     100.0      101.3        1.5        101
                                                                   IW      10.0        9.1        0.8         91
                                                                   IW     100.0      104.0        3.2        104
----------------------------------------------------------------------------------------------------------------
 ARW=Reagent water.
 APOTW=Prechlorination secondary effluent from a municipal sewage treatment plant.
 AIW=Industrial wastewater containing an unidentified acrolein reactant.


                         Table 3--Calibration and QC Acceptance Criteria--Method 603 \a\
----------------------------------------------------------------------------------------------------------------
                                                                             Limit for
                           Parameter                            Range for Q  S ([mu]g/  Range for X   Range for
                                                                 ([mu]g/L)       L)      ([mu]g/L)    P, Ps (%)
----------------------------------------------------------------------------------------------------------------
Acrolein......................................................    45.9-54.1        4.6    42.9-60.1       88-118

[[Page 64]]

 
Acrylonitrile.................................................    41.2-58.8        9.9    33.1-69.9       71-135
----------------------------------------------------------------------------------------------------------------
a=Criteria were calculated assuming a QC check sample concentration of 50 [mu]g/L.9
Q=Concentration measured in QC check sample, in [mu]g/L (Section 7.5.3).
s=Standard deviation of four recovery measurements, in [mu]g/L (Section 8.2.4).
X=Average recovery for four recovery measurements, in [mu]g/L (Section 8.2.4).
P, Ps=Percent recovery measured (Section 8.3.2, Section 8.4.2).

[GRAPHIC] [TIFF OMITTED] TC02JY92.008


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[GRAPHIC] [TIFF OMITTED] TC02JY92.009


[[Page 66]]

[GRAPHIC] [TIFF OMITTED] TC02JY92.010


[[Page 67]]

[GRAPHIC] [TIFF OMITTED] TC02JY92.011

                           Method 604--Phenols

                        1. Scope and Application

    1.1  This method covers the determination of phenol and certain 
substituted phenols. The following parameters may be determined by this 
method:

------------------------------------------------------------------------
                                                    STORET
                    Parameter                         No.      CAS No.
------------------------------------------------------------------------
4-Chloro-3-methylphenol..........................     34452      59-50-7
2--Chlorophenol..................................     34586      95-57-8
2,4-Dichlorophenol...............................     34601     120-83-2
2,4-Dimethylphenol...............................     34606     105-67-9
2,4-Dinitrophenol................................     34616      51-28-5
2-Methyl-4,6-dinitrophenol.......................     34657     534-52-1
2-Nitrophenol....................................     34591      88-75-5
4-Nitrophenol....................................     34646     100-02-7
Pentachlorophenol................................     39032      87-86-5
Phenol...........................................     34694     108-95-2
2,4,6-Trichlorophenol............................     34621      88-06-2
------------------------------------------------------------------------
 

    1.2  This is a flame ionization detector gas chromatographic (FIDGC) 
method applicable to the determination of the compounds listed above in 
municipal and industrial discharges as provided under 40 CFR 136.1. When 
this method is used to analyze unfamiliar samples for any or all of the 
compounds above, compound identifications should be supported by at 
least one additional qualitative technique. This method describes 
analytical conditions for derivatization, cleanup, and electron capture 
detector gas chromatography (ECDGC) that can be used to confirm 
measurements made by FIDGC. Method 625 provides gas chromatograph/mass 
spectrometer (GC/MS) conditions appropriate for the qualitative and 
quantitative confirmation of results for all of the parameters listed 
above, using the extract produced by this method.
    1.3 The method detection limit (MDL, defined in Section 14.1) \1\ 
for each parameter is listed in Table 1. The MDL for a specific 
wastewater may differ from those listed, depending upon the nature of 
interferences in the sample matrix. The MDL listed in Table 1 for each 
parameter was achieved with a flame ionization detector (FID). The MDLs 
that were achieved when the derivatization cleanup and electron capture 
detector (ECD) were employed are presented in Table 2.

[[Page 68]]

    1.4  Any modification of this method, beyond those expressly 
permitted, shall be considered as a major modification subject to 
application and approval of alternate test procedures under 40 CFR 136.4 
and 136.5.
    1.5  This method is restricted to use by or under the supervision of 
analysts experienced in the use of a gas chromatograph and in the 
interpretation of gas chromatograms. Each analyst must demonstrate the 
ability to generate acceptable results with this method using the 
procedure described in Section 8.2.

                          2. Summary of Method

    2.1  A measured volume of sample, approximately 1-L, is acidified 
and extracted with methylene chloride using a separatory funnel. The 
methylene chloride extract is dried and exchanged to 2-propanol during 
concentration to a volume of 10 mL or less. The extract is separated by 
gas chromatography and the phenols are then measured with an FID.\2\
    2.2  A preliminary sample wash under basic conditions can be 
employed for samples having high general organic and organic base 
interferences.
    2.3  The method also provides for a derivatization and column 
chromatography cleanup procedure to aid in the elimination of 
interferences.2,3 The derivatives are analyzed by ECDGC.

                            3. Interferences

    3.1  Method interferences may be caused by contaminants in solvents, 
reagents, glassware, and other sample processing hardware that lead to 
discrete artifacts and/or elevated baselines in gas chromatograms. All 
of these materials must be routinely demonstrated to be free from 
interferences under the conditions of the analysis by running laboratory 
reagent blanks as described in Section 8.1.3.
    3.1.1  Glassware must be scrupulously cleaned.\4\ Clean all 
glassware as soon as possible after use by rinsing with the last solvent 
used in it. Solvent rinsing should be followed by detergent washing with 
hot water, and rinses with tap water and distilled water. The glassware 
should then be drained dry, and heated in a muffle furnace at 400  deg.C 
for 15 to 30 min. Some thermally stable materials, such as PCBs, may not 
be eliminated by this treatment. Solvent rinses with acetone and 
pesticide quality hexane may be substituted for the muffle furnace 
heating. Thorough rinsing with such solvents usually eliminates PCB 
interference. Volumetric ware should not be heated in a muffle furnace. 
After drying and cooling, glassware should be sealed and stored in a 
clean environment to prevent any accumulation of dust or other 
contaminants. Store inverted or capped with aluminum foil.
    3.1.2  The use of high purity reagents and solvents helps to 
minimize interference problems. Purification of solvents by distillation 
in all-glass systems may be required.
    3.2  Matrix interferences may be caused by contaminants that are 
coextracted from the sample. The extent of matrix interferences will 
vary considerably from source to source, depending upon the nature and 
diversity of the industrial complex or municipality being sampled. The 
derivatization cleanup procedure in Section 12 can be used to overcome 
many of these interferences, but unique samples may require additional 
cleanup approaches to achieve the MDL listed in Tables 1 and 2.
    3.3  The basic sample wash (Section 10.2) may cause significantly 
reduced recovery of phenol and 2,4-dimethylphenol. The analyst must 
recognize that results obtained under these conditions are minimum 
concentrations.

                                4. Safety

    4.1  The toxicity or carcinogenicity of each reagent used in this 
mothod has not been precisely defined; however, each chemical compound 
should be treated as a potential health hazard. From this viewpoint, 
exposure to these chemicals must be reduced to the lowest possible level 
by whatever means available. The laboratory is responsible for 
maintaining a current awareness file of OSHA regulations regarding the 
safe handling of the chemicals specified in this method. A reference 
file of material data handling sheets should also be made available to 
all personnel involved in the chemical analysis. Additional references 
to laboratory safety are available and have been identified 
5--7 for the information of analyst.
    4.2  Special care should be taken in handling pentafluorobenzyl 
bromide, which is a lachrymator, and 18-crown-6-ether, which is highly 
toxic.

                       5. Apparatus and Materials

    5.1  Sampling equipment, for discrete or composite sampling.
    5.1.1  Grab sample bottle--1-L or 1-qt, amber glass, fitted with a 
screw cap lined with Teflon. Foil may be substituted for Teflon if the 
sample is not corrosive. If amber bottles are not available, protect 
samples from light. The bottle and cap liner must be washed, rinsed with 
acetone or methylene chloride, and dried before use to minimize 
contamination.
    5.1.2  Automatic sampler (optional)--The sampler must incorporate 
glass sample containers for the collection of a minimum of 250 mL of 
sample. Sample containers must be kept refrigerated at 4  deg.C and 
protected from light during compositing. If the sampler uses a 
peristaltic pump, a minimum length of compressible silicone rubber 
tubing may be

[[Page 69]]

used. Before use, however, the compressible tubing should be thoroughly 
rinsed with methanol, followed by repeated rinsings with distilled water 
to minimize the potential for contamination of the sample. An 
integrating flow meter is required to collect flow proportional 
composites.
    5.2  Glassware (All specifications are suggested. Catalog numbers 
are included for illustration only.):
    5.2.1  Separatory funnel--2-L, with Teflon stopcock.
    5.2.2  Drying column--Chromatographic column, 400 mm long x 19 mm 
ID, with coarse frit filter disc.
    5.2.3  Chromatographic column--100 mm long x 10 mm ID, with Teflon 
stopcock.
    5.2.4  Concentrator tube, Kuderna-Danish--10-mL, graduated (Kontes 
K-570050-1025 or equivalent). Calibration must be checked at the volumes 
employed in the test. Ground glass stopper is used to prevent 
evaporation of extracts.
    5.2.5  Evaporative flask, Kuderna-Danish--500-mL (Kontes K-570001-
0500 or equivalent). Attach to concentrator tube with springs.
    5.2.6  Snyder column, Kuderna-Danish--Three-ball macro (Kontes K-
503000-0121 or equivalent).
    5.2.7  Snyder column, Kuderna-Danish--Two-ball micro (Kontes K-
569001-0219 or equivalent).
    5.2.8  Vials--10 to 15-mL, amber glass, with Teflon-lined screw cap.
    5.2.9  Reaction flask--15 to 25-mL round bottom flask, with standard 
tapered joint, fitted with a water-cooled condenser and U-shaped drying 
tube containing granular calcium chloride.
    5.3  Boiling chips--Approximately 10/40 mesh. Heat to 400  deg.C for 
30 min or Soxhlet extract with methylene chloride.
    5.4  Water bath--Heated, with concentric ring cover, capable of 
temperature control (2 deg.C). The bath should be used in a 
hood.
    5.5  Balance--Analytical, capable of accurately weighting 0.0001 g.
    5.6  Gas chromatograph--An analytical system complete with a 
temperature programmable gas chromatograph suitable for on-column 
injection and all required accessories including syringes, analytical 
columns, gases, detector, and strip-chart recorder. A data system is 
recommended for measuring peak areas.
    5.6.1  Column for underivatized phenols--1.8 m long x 2 mm ID glass, 
packed with 1% SP-1240DA on Supelcoport (80/100 mesh) or equivalent. 
This column was used to develop the method performance statements in 
Section 14. Guidelines for the use of alternate column packings are 
provided in Section 11.1.
    5.6.2  Column for derivatized phenols--1.8 m long x 2 mm ID glass, 
packed with 5% OV-17 on Chromosorb W-AW-DMCS (80/100 mesh) or 
equivalent. This column has proven effective in the analysis of 
wastewaters for derivatization products of the parameters listed in the 
scope (Section 1.1), and was used to develop the method performance 
statements in Section 14. Guidelines for the use of alternate column 
packings are provided in Section 11.1.
    5.6.3  Detectors--Flame ionization and electron capture detectors. 
The FID is used when determining the parent phenols. The ECD is used 
when determining the derivatized phenols. Guidelines for the use of 
alternatve detectors are provided in Section 11.1.

                               6. Reagents

    6.1  Reagent water--Reagent water is defined as a water in which an 
interferent is not observed at the MDL of the parameters of interest.
    6.2  Sodium hydroxide solution (10 N)--Dissolve 40 g of NaOH (ACS) 
in reagent water and dilute to 100 mL.
    6.3  Sodium hydroxide solution (1 N)--Dissolve 4 g of NaOH (ACS) in 
reagent water and dilute to 100 mL.
    6.4  Sodium sulfate--(ACS) Granular, anhydrous. Purify by heating at 
400 deg.C for 4 h in a shallow tray.
    6.5  Sodium thiosulfate--(ACS) Granular.
    6.6  Sulfuric acid (1+1)--Slowly, add 50 mL of 
H2SO4 (ACS, sp. gr. 1.84) to 50 mL of reagent 
water.
    6.7  Sulfuric acid (1 N)--Slowly, add 58 mL of 
H2SO4 (ACS, sp. gr. 1.84) to reagent water and 
dilute to 1 L.
    6.8  Potassium carbonate--(ACS) Powdered.
    6.9  Pentafluorobenzyl bromide ([alpha]-Bromopentafluorotoluene)--
97% minimum purity.
    Note: This chemical is a lachrymator. (See Section 4.2.)
    6.10  18-crown-6-ether (1,4,7,10,13,16-Hexaoxacyclooctadecane)--98% 
minimum purity.
    Note: This chemical is highly toxic.
    6.11  Derivatization reagent--Add 1 mL of pentafluorobenzyl bromide 
and 1 g of 18-crown-6-ether to a 50-mL volumetric flask and dilute to 
volume with 2-propanol. Prepare fresh weekly. This operation should be 
carried out in a hood. Store at 4  deg.C and protect from light.
    6.12  Acetone, hexane, methanol, methylene chloride, 2-propanol, 
toluene--Pesticide quality or equivalent.
    6.13  Silica gel--100/200 mesh, Davison, grade-923 or equivalent. 
Activate at 130  deg.C overnight and store in a desiccator.
    6.14  Stock standard solutions (1.00 [mu]g/[mu]L)--Stock standard 
solutions may be prepared from pure standard materials or purchased as 
certified solutions.
    6.14.1  Prepare stock standard solutions by accurately weighing 
about 0.0100 g of pure material. Dissolve the material in 2-propanol

[[Page 70]]

and dilute to volume in a 10-mL volumetric flask. Larger volumes can be 
used at the convenience of the analyst. When compound purity is assayed 
to be 96% or greater, the weight can be used without correction to 
calculate the concentration of the stock standard. Commercially prepared 
stock standards can be used at any concentration if they are certified 
by the manufacturer or by an independent source.
    6.14.2  Transfer the stock standard solutions into Teflon-sealed 
screw-cap bottles. Store at 4  deg.C and protect from light. Stock 
standard solutions should be checked frequently for signs of degradation 
or evaporation, especially just prior to preparing calibration standards 
from them.
    6.14.3  Stock standard solutions must be replaced after six months, 
or sooner if comparison with check standards indicates a problem.
    6.15  Quality control check sample concentrate--See Section 8.2.1.

                             7. Calibration

    7.1  To calibrate the FIDGC for the anaylsis of underivatized 
phenols, establish gas chromatographic operating conditions equivalent 
to those given in Table 1. The gas chromatographic system can be 
calibrated using the external standard technique (Section 7.2) or the 
internal standard technique (Section 7.3).
    7.2  External standard calibration procedure for FIDGC:
    7.2.1  Prepare calibration standards at a minimum of three 
concentration levels for each parameter of interest by adding volumes of 
one or more stock standards to a volumetric flask and diluting to volume 
with 2-propanol. One of the external standards should be at a 
concentration near, but above, the MDL (Table 1) and the other 
concentrations should correspond to the expected range of concentrations 
found in real samples or should define the working range of the 
detector.
    7.2.2  Using injections of 2 to 5 [mu]l, analyze each calibration 
standard according to Section 11 and tabulate peak height or area 
responses against the mass injected. The results can be used to prepare 
a calibration curve for each compound. Alternatively, if the ratio of 
response to amount injected (calibration factor) is a constant over the 
working range (<10% relative standard deviation, RSD), linearity through 
the origin can be assumed and the average ratio or calibration factor 
can be used in place of a calibration curve.
    7.3  Internal standard calibration procedure for FIDGC--To use this 
approach, the analyst must select one or more internal standards that 
are similar in analytical behavior to the compounds of interest. The 
analyst must further demonstrate that the measurement of the internal 
standard is not affected by method or matrix interferences. Because of 
these limitations, no internal standard can be suggested that is 
applicable to all samples.
    7.3.1  Prepare calibration standards at a minimum of three 
concentration levels for each parameter of interest by adding volumes of 
one or more stock standards to a volumetric flask. To each calibration 
standard, add a known constant amount of one or more internal standards, 
and dilute to volume with 2-propanol. One of the standards should be at 
a concentration near, but above, the MDL and the other concentrations 
should correspond to the expected range of concentrations found in real 
samples or should define the working range of the detector.
    7.3.2  Using injections of 2 to 5 [mu]L, analyze each calibration 
standard according to Section 11 and tabulate peak height or area 
responses against concentration for each compound and internal standard. 
Calculate response factors (RF) for each compound using Equation 1.

 
                                                                   RF=      (As)(Cis)    (Ais)(Cs)
----------------------------------------------------------------------------------------------------------------
 

                                                              Equation 1

where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Cis=Concentration of the internal standard ([mu]g/L).

Cs=Concentration of the parameter to be measured ([mu]g/L).

    If the RF value over the working range is a constant (<10% RSD), the 
RF can be assumed to be invariant and the average RF can be used for 
calculations. Alternatively, the results can be used to plot a 
calibration curve of response ratios, As/Ais, vs. 
RF.
    7.4  The working calibration curve, calibration factor, or RF must 
be verified on each working day by the measurement of one or more 
calibration standards. If the response for any parameter varies from the 
predicted response by more than 15%, a new calibration curve 
must be prepared for that compound.
    7.5  To calibrate the ECDGC for the analysis of phenol derivatives, 
establish gas chromatographic operating conditions equivalent to those 
given in Table 2.
    7.5.1  Prepare calibration standards at a minimum of three 
concentration levels for each parameter of interest by adding volumes of 
one or more stock standards to a volumetric flask and diluting to volume 
with 2-propanol. One of the external standards should be at a 
concentration near, but above, the MDL (Table 2) and the other 
concentrations should correspond to the expected

[[Page 71]]

range of concentrations found in real samples or should define the 
working range of the detector.
    7.5.2  Each time samples are to be derivatized, simultaneously treat 
a 1-mL aliquot of each calibration standard as described in Section 12.
    7.5.3  After derivatization, analyze 2 to 5 [mu]L of each column 
eluate collected according to the method beginning in Section 12.8 and 
tabulate peak height or area responses against the calculated equivalent 
mass of underivatized phenol injected. The results can be used to 
prepare a calibration curve for each compound.
    7.6  Before using any cleanup procedure, the analyst must process a 
series of calibration standards through the procedure to validate 
elution patterns and the absence of interferences from the reagents.

                           8. Quality Control

    8.1  Each laboratory that uses this method is required to operate a 
formal quality control program. The minimum requirements of this program 
consist of an initial demonstration of laboratory capability and an 
ongoing analysis of spiked samples to evaluate and document data 
quality. The laboratory must maintain records to document the quality of 
data that is generated. Ongoing data quality checks are compared with 
established performance criteria to determine if the results of analyses 
meet the performance characteristics of the method. When results of 
sample spikes indicate atypical method performance, a quality control 
check standard must be analyzed to confirm that the measurements were 
performed in an in-control mode of operation.
    8.1.1  The analyst must make an initial, one-time, demonstration of 
the ability to generate acceptable accuracy and precision with this 
method. This ability is established as described in Section 8.2.
    8.1.2  In recognition of advances that are occurring in 
chromatography, the analyst is permitted certain options (detailed in 
Sections 10.6 and 11.1) to improve the separations or lower the cost of 
measurements. Each time such a modification is made to the method, the 
analyst is required to repeat the procedure in Section 8.2.
    8.1.3  Before processing any samples the analyst must analyze a 
reagent water blank to demonstrate that interferences from the 
analytical system and glassware are under control. Each time a set of 
samples is extracted or reagents are changed a reagent water blank must 
be processed as a safeguard against laboratory contamination.
    8.1.4  The laboratory must, on an ongoing basis, spike and analyze a 
minimum of 10% of all samples to monitor and evaluate laboratory data 
quality. This procedure is described in Section 8.3.
    8.1.5  The laboratory must, on an ongoing basis, demonstrate through 
the analyses of quality control check standards that the operation of 
the measurement system is in control. This procedure is described in 
Section 8.4. The frequency of the check standard analyses is equivalent 
to 10% of all samples analyzed but may be reduced if spike recoveries 
from samples (Section 8.3) meet all specified quality control criteria.
    8.1.6  The laboratory must maintain performance records to document 
the quality of data that is generated. This procedure is described in 
Section 8.5.
    8.2  To establish the ability to generate acceptable accuracy and 
precision, the analyst must perform the following operations.
    8.2.1  A quality control (QC) check sample concentrate is required 
containing each parameter of interest at a concentration of 100 [mu]g/mL 
in 2-propanol. The QC check sample concentrate must be obtained from the 
U.S. Environmental Protection Agency, Environmental Monitoring and 
Support Laboratory in Cincinnati, Ohio, if available. If not available 
from that source, the QC check sample concentrate must be obtained from 
another external source. If not available from either source above, the 
QC check sample concentrate must be prepared by the laboratory using 
stock standards prepared independently from those used for calibration.
    8.2.2  Using a pipet, prepare QC check samples at a concentration of 
100 [mu]g/L by adding 1.00 mL of QC check sample concentrate to each of 
four 1-L aliquots of reagent water.
    8.2.3  Analyze the well-mixed QC check samples according to the 
method beginning in Section 10.
    8.2.4  Calculate the average recovery (X) in [mu]g/L, and the 
standard deviation of the recovery (s) in [mu]g/L, for each parameter 
using the four results.
    8.2.5  For each parameter compare s and X with the corresponding 
acceptance criteria for precision and accuracy, respectively, found in 
Table 3. If s and X for all parameters of interest meet the acceptance 
criteria, the system performance is acceptable and analysis of actual 
samples can begin. If any individual s exceeds the precision limit or 
any individual X falls outside the range for accuracy, the system 
performance is unacceptable for that parameter.
    Note: The large number of parameters in Talbe 3 present a 
substantial probability that one or more will fail at least one of the 
acceptance criteria when all parameters are analyzed.
    8.2.6  When one or more of the parameters tested fail at least one 
of the acceptance criteria, the analyst must proceed according to 
Section 8.2.6.1 or 8.2.6.2.
    8.2.6.1  Locate and correct the source of the problem and repeat the 
test for all parameters of interest beginning with Section 8.2.2.

[[Page 72]]

    8.2.6.2  Beginning with Section 8.2.2, repeat the test only for 
those parameters that failed to meet criteria. Repeated failure, 
however, will confirm a general problem with the measurement system. If 
this occurs, locate and correct the source of the problem and repeat the 
test for all compounds of interest beginning with Section 8.2.2.
    8.3  The laboratory must, on an ongoing basis, spike at least 10% of 
the samples from each sample site being monitored to assess accuracy. 
For laboratories analyzing one to ten samples per month, at least one 
spiked sample per month is required.
    8.3.1  The concentration of the spike in the sample should be 
determined as follows:
    8.3.1.1  If, as in compliance monitoring, the concentration of a 
specific parameter in the sample is being checked against a regulatory 
concentration limit, the spike should be at that limit or 1 to 5 times 
higher than the background concentration determined in Section 8.3.2, 
whichever concentration would be larger.
    8.3.1.2  If the concentration of a specific parameter in the sample 
is not being checked against a limit specific to that parameter, the 
spike should be at 100 [mu]g/L or 1 to 5 times higher than the 
background concentration determined in Section 8.3.2, whichever 
concentration would be larger.
    8.3.1.3  If it is impractical to determine background levels before 
spiking (e.g., maximum holding times will be exceeded), the spike 
concentration should be (1) the regulatory concentration limit, if any, 
or, if none, (2) the larger of either 5 times higher than the expected 
background concentration or 100 [mu]g/L.
    8.3.2  Analyze one sample aliquot to determine the background 
concentration (B) of each parameter. If necessary, prepare a new QC 
check sample concentrate (Section 8.2.1) appropriate for the background 
concentrations in the sample. Spike a second sample aliquot with 1.0 mL 
of the QC check sample concentrate and analyze it to determine the 
concentration after spiking (A) of each parameter. Calculate each 
percent recovery (P) as 100(A-B)%/T, where T is the known true value of 
the spike.
    8.3.3  Compare the percent recovery (P) for each parameter with the 
corresponding QC acceptance criteria found in Table 3. These acceptance 
criteria were calculated to include an allowance for error in 
measurement of both the background and spike concentrations, assuming a 
spike to background ratio of 5:1. This error will be accounted for to 
the extent that the analyst's spike to background ratio approaches 
5:1.8 If spiking was performed at a concentration lower than 
100 [mu]g/L, the analyst must use either the QC acceptance criteria in 
Table 3, or optional QC acceptance criteria calculated for the specific 
spike concentration. To calculate optional acceptance criteria for the 
recovery of a parameter: (1) Calculate accuracy (X') using the equation 
in Table 4, substituting the spike concentration (T) for C; (2) 
calculate overall precision (S') using the equation in Table 4, 
substituting X' for X; (3) calculate the range for recovery at the spike 
concentration as (100 X'/T)2.44(100 S'/T)%.8
    8.3.4  If any individual P falls outside the designated range for 
recovery, that parameter has failed the acceptance criteria. A check 
standard containing each parameter that failed the criteria must be 
analyzed as described in Section 8.4.
    8.4  If any parameter fails the acceptance criteria for recovery in 
Section 8.3, a QC check standard containing each parameter that failed 
must be prepared and analyzed.
    Note: The frequency for the required analysis of a QC check standard 
will depend upon the number of parameters being simultaneously tested, 
the complexity of the sample matrix, and the performance of the 
laboratory.
    8.4.1  Prepare the QC check standard by adding 1.0 mL of QC check 
sample concentrate (Section 8.2.1 or 8.3.2) to 1 L of reagent water. The 
QC check standard needs only to contain the parameters that failed 
criteria in the test in Section 8.3.
    8.4.2  Analyze the QC check standard to determine the concentration 
measured (A) of each parameter. Calculate each percent recovery 
(Ps) as 100 (A/T)%, where T is the true value of the standard 
concentration.
    8.4.3  Compare the percent recovery (Ps) for each 
parameter with the corresponding QC acceptance criteria found in Table 
3. Only parameters that failed the test in Section 8.3 need to be 
compared with these criteria. If the recovery of any such parameter 
falls outside the designated range, the laboratory performance for that 
parameter is judged to be out of control, and the problem must be 
immediately identified and corrected. The analytical result for that 
parameter in the unspiked sample is suspect and may not be reported for 
regulatory compliance purposes.
    8.5  As part of the QC program for the laboratory, method accuracy 
for wastewater samples must be assessed and records must be maintained. 
After the analysis of five spiked wastewater samples as in Section 8.3, 
calculate the average percent recovery (P) and the standard deviation of 
the percent recovery (sp). Express the accuracy assessment as 
a percent recovery interval from P-2sp to P+2sp. 
If P=90% and sp=10%, for example, the accuracy interval is 
expressed as 70-110%. Update the accuracy assessment for each parameter 
on a regular basis (e.g. after each five to ten new accuracy 
measurements).
    8.6.  It is recommended that the laboratory adopt additional quality 
assurance practices for use with this method. The specific practices 
that are most productive depend upon the needs of the laboratory and the 
nature of the samples. Field duplicates

[[Page 73]]

may be analyzed to assess the precision of the environmental 
measurements. When doubt exists over the identification of a peak on the 
chromatogram, confirmatory techniques such as gas chromatography with a 
dissimilar column, specific element detector, or mass spectrometer must 
be used. Whenever possible, the laboratory should analyze standard 
reference materials and participate in relevant performance evaluation 
studies.

            9. Sample Collection, Preservation, and Handling

    9.1  Grab samples must be collected in glass containers. 
Conventional sampling practices 9 should be followed, except 
that the bottle must not be prerinsed with sample before collection. 
Composite samples should be collected in refrigerated glass containers 
in accordance with the requirements of the program. Automatic sampling 
equipment must be as free as possible of Tygon tubing and other 
potential sources of contamination.
    9.2  All samples must be iced or refrigerated at 4  deg.C from the 
time of collection until extraction. Fill the sample bottles and, if 
residual chlorine is present, add 80 mg of sodium thiosulfate per liter 
of sample and mix well. EPA Methods 330.4 and 330.5 may be used for 
measurement of residual chlorine.10 Field test kits are 
available for this purpose.
    9.3  All samples must be extracted within 7 days of collection and 
completely analyzed within 40 days of extraction.2

                          10. Sample Extraction

    10.1  Mark the water meniscus on the side of sample bottle for later 
determination of sample volume. Pour the entire sample into a 2-L 
separatory funnel.
    10.2  For samples high in organic content, the analyst may solvent 
wash the sample at basic pH as prescribed in Sections 10.2.1 and 10.2.2 
to remove potential method interferences. Prolonged or exhaustive 
contact with solvent during the wash may result in low recovery of some 
of the phenols, notably phenol and 2,4-dimethylphenol. For relatively 
clean samples, the wash should be omitted and the extraction, beginning 
with Section 10.3, should be followed.
    10.2.1  Adjust the pH of the sample to 12.0 or greater with sodium 
hydroxide solution.
    10.2.2  Add 60 mL of methylene chloride to the sample by shaking the 
funnel for 1 min with periodic venting to release excess pressure. 
Discard the solvent layer. The wash can be repeated up to two additional 
times if significant color is being removed.
    10.3  Adjust the sample to a pH of 1 to 2 with sulfuric acid.
    10.4  Add 60 mL of methylene chloride to the sample bottle, seal, 
and shake 30 s to rinse the inner surface. Transfer the solvent to the 
separatory funnel and extract the sample by shaking the funnel for 2 
min. with periodic venting to release excess pressure. Allow the organic 
layer to separate from the water phase for a minimum of 10 min. If the 
emulsion interface between layers is more than one-third the volume of 
the solvent layer, the analyst must employ mechanical techniques to 
complete the phase separation. The optimum technique depends upon the 
sample, but may include stirring, filtration of the emulsion through 
glass wool, centrifugation, or other physical methods. Collect the 
methylene chloride extract in a 250-mL Erlenmeyer flask.
    10.5  Add a second 60-mL volume of methylene chloride to the sample 
bottle and repeat the extraction procedure a second time, combining the 
extracts in the Erlenmeyer flask. Perform a third extraction in the same 
manner.
    10.6  Assemble a Kuderna-Danish (K-D) concentrator by attaching a 
10-mL concentrator tube to a 500-mL evaporative flask. Other 
concentration devices or techniques may be used in place of the K-D 
concentrator if the requirements of Section 8.2 are met.
    10.7  Pour the combined extract through a solvent-rinsed drying 
column containing about 10 cm of anhydrous sodium sulfate, and collect 
the extract in the K-D concentrator. Rinse the Erlenmeyer flask and 
column with 20 to 30 mL of methylene chloride to complete the 
quantitative transfer.
    10.8  Add one or two clean boiling chips to the evaporative flask 
and attach a three-ball Snyder column. Prewet the Snyder column by 
adding about 1 mL of methylene chloride to the top. Place the K-D 
apparatus on a hot water bath (60 to 65  deg.C) so that the concentrator 
tube is partially immersed in the hot water, and the entire lower 
rounded surface of the flask is bathed with hot vapor. Adjust the 
vertical position of the apparatus and the water temperature as required 
to complete the concentration in 15 to 20 min. At the proper rate of 
distillation the balls of the column will actively chatter but the 
chambers will not flood with condensed solvent. When the apparent volume 
of liquid reaches 1 mL, remove the K-D apparatus and allow it to drain 
and cool for at least 10 min.
    10.9  Increase the temperature of the hot water bath to 95 to 100 
deg.C. Remove the Synder column and rinse the flask and its lower joint 
into the concentrator tube with 1 to 2 mL of 2-propanol. A 5-mL syringe 
is recommended for this operation. Attach a two-ball micro-Snyder column 
to the concentrator tube and prewet the column by adding about 0.5 mL of 
2-propanol to the top. Place the micro-K-D apparatus on the water bath 
so that the concentrator tube is partially immersed in the hot water. 
Adjust the vertical position of the apparatus and the water temperature 
as required to complete

[[Page 74]]

concentration in 5 to 10 min. At the proper rate of distillation the 
balls of the column will actively chatter but the chambers will not 
flood. When the apparent volume of liquid reaches 2.5 mL, remove the K-D 
apparatus and allow it to drain and cool for at least 10 min. Add an 
additional 2 mL of 2-propanol through the top of the micro-Snyder column 
and resume concentrating as before. When the apparent volume of liquid 
reaches 0.5 mL, remove the K-D apparatus and allow it to drain and cool 
for at least 10 min.
    10.10  Remove the micro-Snyder column and rinse its lower joint into 
the concentrator tube with a minimum amount of 2-propanol. Adjust the 
extract volume to 1.0 mL. Stopper the concentrator tube and store 
refrigerated at 4  deg.C if further processing will not be performed 
immediately. If the extract will be stored longer than two days, it 
should be transferred to a Teflon-sealed screw-cap vial. If the sample 
extract requires no further cleanup, proceed with FIDGC analysis 
(Section 11). If the sample requires further cleanup, proceed to Section 
12.
    10.11  Determine the original sample volume by refilling the sample 
bottle to the mark and transferring the liquid to a 1000-mL graduated 
cylinder. Record the sample volume to the nearest 5 mL.

            11. Flame Ionization Detector Gas Chromatography

    11.1  Table 1 summarizes the recommended operating conditions for 
the gas chromatograph. Included in this table are retention times and 
MDL that can be achieved under these conditions. An example of the 
separations achieved by this column is shown in Figure 1. Other packed 
or capillary (open-tubular) columns, chromatographic conditions, or 
detectors may be used if the requirements of Section 8.2 are met.
    11.2  Calibrate the system daily as described in Section 7.
    11.3  If the internal standard calibration procedure is used, the 
internal standard must be added to the sample extract and mixed 
thoroughly immediately before injection into the gas chromatograph.
    11.4  Inject 2 to 5 [mu]L of the sample extract or standard into the 
gas chromatograph using the solvent-flush technique.11 
Smaller (1.0 [mu]L) volumes may be injected if automatic devices are 
employed. Record the volume injected to the nearest 0.05 [mu]L, and the 
resulting peak size in area or peak height units.
    11.5  Identify the parameters in the sample by comparing the 
retention times of the peaks in the sample chromatogram with those of 
the peaks in standard chromatograms. The width of the retention time 
window used to make identifications should be based upon measurements of 
actual retention time variations of standards over the course of a day. 
Three times the standard deviation of a retention time for a compound 
may be used to calculate a suggested window size; however, the 
experience of the analyst should weigh heavily in the interpretation of 
chromatograms.
    11.6  If the response for a peak exceeds the working range of the 
system, dilute the extract and reanalyze.
    11.7  If the measurement of the peak response is prevented by the 
presence of interferences, an alternative gas chromatographic procedure 
is required. Section 12 describes a derivatization and column 
chromatographic procedure which has been tested and found to be a 
practical means of analyzing phenols in complex extracts.

   12. Derivatization and Electron Capture Detector Gas Chromatography

    12.1  Pipet a 1.0-mL aliquot of the 2-propanol solution of standard 
or sample extract into a glass reaction vial. Add 1.0 mL of derivatizing 
reagent (Section 6.11). This amount of reagent is sufficient to 
derivatize a solution whose total phenolic content does not exceed 0.3 
mg/mL.
    12.2  Add about 3 mg of potassium carbonate to the solution and 
shake gently.
    12.3  Cap the mixture and heat it for 4 h at 80  deg.C in a hot 
water bath.
    12.4  Remove the solution from the hot water bath and allow it to 
cool.
    12.5  Add 10 mL of hexane to the reaction flask and shake vigorously 
for 1 min. Add 3.0 mL of distilled, deionized water to the reaction 
flask and shake for 2 min. Decant a portion of the organic layer into a 
concentrator tube and cap with a glass stopper.
    12.6  Place 4.0 g of silica gel into a chromatographic column. Tap 
the column to settle the silica gel and add about 2 g of anhydrous 
sodium sulfate to the top.
    12.7  Preelute the column with 6 mL of hexane. Discard the eluate 
and just prior to exposure of the sodium sulfate layer to the air, pipet 
onto the column 2.0 mL of the hexane solution (Section 12.5) that 
contains the derivatized sample or standard. Elute the column with 10.0 
mL of hexane and discard the eluate. Elute the column, in order, with: 
10.0 mL of 15% toluene in hexane (Fraction 1); 10.0 mL of 40% toluene in 
hexane (Fraction 2); 10.0 mL of 75% toluene in hexane (Fraction 3); and 
10.0 mL of 15% 2-propanol in toluene (Fraction 4). All elution mixtures 
are prepared on a volume: volume basis. Elution patterns for the 
phenolic derivatives are shown in Table 2. Fractions may be combined as 
desired, depending upon the specific phenols of interest or level of 
interferences.
    12.8  Analyze the fractions by ECDGC. Table 2 summarizes the 
recommended operating conditions for the gas chromatograph. Included in 
this table are retention times and MDL that can be achieved under these 
conditions. An example of the separations

[[Page 75]]

achieved by this column is shown in Figure 2.
    12.9  Calibrate the system daily with a minimum of three aliquots of 
calibration standards, containing each of the phenols of interest that 
are derivatized according to Section 7.5.
    12.10  Inject 2 to 5 [mu]L of the column fractions into the gas 
chromatograph using the solvent-flush technique. Smaller (1.0 [mu]L) 
volumes can be injected if automatic devices are employed. Record the 
volume injected to the nearest 0.05 [mu]L, and the resulting peak size 
in area or peak height units. If the peak response exceeds the linear 
range of the system, dilute the extract and reanalyze.

                            13. Calculations

    13.1  Determine the concentration of individual compounds in the 
sample analyzed by FIDGC (without derivatization) as indicated below.
    13.1.1  If the external standard calibration procedure is used, 
calculate the amount of material injected from the peak response using 
the calibration curve or calibration factor determined in Section 7.2.2. 
The concentration in the sample can be calculated from Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.098

                                                              Equation 2

where:
A=Amount of material injected (ng).
Vi=Volume of extract injected ([mu]L).
Vt=Volume of total extract ([mu]L).
Vs=Volume of water extracted (mL).

    13.1.2  If the internal standard calibration procedure is used, 
calculate the concentration in the sample using the response factor (RF) 
determined in Section 7.3.2 and Equation 3.
[GRAPHIC] [TIFF OMITTED] TC15NO91.099

                                                              Equation 3

where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Is=Amount of internal standard added to each extract ([mu]g).
Vo=Volume of water extracted (L).

    13.2  Determine the concentration of individual compounds in the 
sample analyzed by derivatization and ECDGC according to Equation 4.
[GRAPHIC] [TIFF OMITTED] TC15NO91.100

                                                              Equation 4

where:
A=Mass of underivatized phenol represented by area of peak in sample 
chromatogram, determined from calibration curve in Section 7.5.3 (ng).
Vi=Volume of eluate injected ([mu]L).
Vt=Total volume of column eluate or combined fractions from 
which Vi was taken ([mu]L).
Vs=Volume of water extracted in Section 10.10 (mL).
B=Total volume of hexane added in Section 12.5 (mL).
C=Volume of hexane sample solution added to cleanup column in Section 
12.7 (mL).
D=Total volume of 2-propanol extract prior to derivatization (mL).
E=Volume of 2-propanol extract carried through derivatization in Section 
12.1 (mL).

    13.3  Report results in [mu]g/L without correction for recovery 
data. All QC data obtained should be reported with the sample results.

                         14. Method Performance

    14.1  The method detection limit (MDL) is defined as the minimum 
concentration of a substance that can be measured and reported with 99% 
confidence that the value is above zero.1 The MDL 
concentrations listed in Tables 1 and 2 were obtained using reagent 
water.12 Similar results were achieved using representative 
wastewaters. The MDL actually achieved in a given analysis will vary 
depending on instrument sensitivity and matrix effects.
    14.2  This method was tested by 20 laboratories using reagent water, 
drinking water, surface water, and three industrial wastewaters spiked 
as six concentrations over the range 12 to 450 [mu]g/L.\13\ Single 
operator precision, overall precision, and method accuracy were found to 
be directly related to the concentration of the parameter and 
essentially independent of the sample matrix. Linear equations to 
describe these relationships for a flame ionization detector are 
presented in Table 4.

                               References

    1. 40 CFR part 136, appendix B.
    2. ``Determination of Phenols in Industrial and Municipal 
Wastewaters,'' EPA 600/4-84-ABC, National Technical Information Service, 
PBXYZ, Springfield, Virginia 22161, November 1984.
    3. Kawahara, F. K. ``Microdetermination of Derivatives of Phenols 
and Mercaptans by

[[Page 76]]

Means of Electron Capture Gas Chromatography,'' Analytical Chemistry, 
40, 1009 (1968).
    4. ASTM Annual Book of Standards, Part 31, D3694-78. ``Standard 
Practices for Preparation of Sample Containers and for Preservation of 
Organic Constituents,'' American Society for Testing and Materials, 
Philadelphia.
    5. ``Carcinogens--Working With Carcinogens,'' Department of Health, 
Education, and Welfare, Public Health Service, Center for Disease 
Control, National Institute for Occupational Safety and Health, 
Publication No. 77-206, August 1977.
    6. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR 
part 1910), Occupational Safety and Health Administration, OSHA 2206 
(Revised, January 1976).
    7. ``Safety in Academic Chemistry Laboratories,'' American Chemical 
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
    8. Provost, L. P., and Elder, R. S. ``Interpretation of Percent 
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44 
used in the equation in Section 8.3.3 is two times the value 1.22 
derived in this report.)
    9. ASTM Annual Book of Standards, Part 31, D3370-76. ``Standard 
Practices for Sampling Water,'' American Society for Testing and 
Materials, Philadelphia.
    10. ``Methods 330.4 (Titrimetric, DPD-FAS) and 330.5 
(Spectrophotometric, DPD) for Chlorine, Total Residual,'' Methmds for 
Chemical Analysis of Water and Wastes, EPA-600/4-79-020, U.S. 
Environmental Protection Agency, Environmental Monitoring and Support 
Laboratory, Cincinnati, Ohio 45268, March 1979.
    11. Burke, J. A. ``Gas Chromatography for Pesticide Residue 
Analysis; Some Practical Aspects,'' Journal of the Association of 
Official Analytical Chemists, 48, 1037 (1965).
    12. ``Development of Detection Limits, EPA Method 604, Phenols,'' 
Special letter report for EPA Contract 68-03-2625, U.S. Environmental 
Protection Agency, Environmental Monitoring and Support Laboratory, 
Cincinnati, Ohio 45268.
    13. ``EPA Method Study 14 Method 604-Phenols,'' EPA 600/4-84-044, 
National Technical Information Service, PB84-196211, Springfield, 
Virginia 22161, May 1984.

     Table 1--Chromatographic Conditions and Method Detection Limits
------------------------------------------------------------------------
                                                               Method
                                                 Retention    detection
                   Parameter                    time (min)  limit ([mu]g/
                                                                 L)
------------------------------------------------------------------------
2-Chlorophenol................................        1.70          0.31
2-Nitrophenol.................................        2.00          0.45
Phenol........................................        3.01          0.14
2,4-Dimethylphenol............................        4.03          0.32
2,4-Dichlorophenol............................        4.30          0.39
2,4,6-Trichlorophenol.........................        6.05          0.64
4-Chloro-3-methylphenol.......................        7.50          0.36
2,4-Dinitrophenol.............................       10.00         13.0
2-Methyl-4,6-dinitrophenol....................       10.24         16.0
Pentachlorophenol.............................       12.42          7.4
4-Nitrophenol.................................       24.25          2.8
------------------------------------------------------------------------
Column conditions: Supelcoport (80/100 mesh) coated with 1% SP-1240DA
  packed in a 1.8 m long x 2 mm ID glass column with nitrogen carrier
  gas at 30 mL/min flow rate. Column temperature was 80  deg.C at
  injection, programmed immediately at 8  deg.C/min to 150  deg.C final
  temperature. MDL were determined with an FID.


          Table 2--Silica Gel Fractionation and Electron Capture Gas Chromatography of PFBB Derivatives
----------------------------------------------------------------------------------------------------------------
                                                                   Percent recovery by                  Method
                                                                       fraction a          Retention   detection
                       Parent compound                        ----------------------------    time       limit
                                                                 1      2      3      4      (min)     ([mu]g/L)
----------------------------------------------------------------------------------------------------------------
2-Chlorophenol...............................................  .....     90      1  .....        3.3        0.58
2-Nitrophenol................................................  .....  .....      9     90        9.1        0.77
Phenol.......................................................  .....     90     10  .....        1.8        2.2
2,4-Dimethylphenol...........................................  .....     95      7  .....        2.9        0.63
2,4-Dichlorophenol...........................................  .....     95      1  .....        5.8        0.68
2,4,6-Trichlorophenol........................................     50     50  .....  .....        7.0        0.58
4-Chloro-3-methylphenol......................................  .....     84     14  .....        4.8        1.8
Pentachlorophenol............................................     75     20  .....  .....       28.8        0.59
4-Nitrophenol................................................  .....  .....      1     90       14.0        0.70
----------------------------------------------------------------------------------------------------------------
Column conditions: Chromosorb W-AW-DMCS (80/100 mesh) coated with 5% OV-17 packed in a 1.8 m long x 2.0 mm ID
  glass column with 5% methane/95% argon carrier gas at 30 mL/min flow rate. Column temperature held isothermal
  at 200  deg.C. MDL were determined with an ECD.
 
a Eluant composition:
    Fraction 1--15% toluene in hexane.
    Fraction 2--40% toluene in hexane.
    Fraction 3--75% toluene in hexane.
    Fraction 4--15% 2-propanol in toluene.


[[Page 77]]


                                   Table 3--QC Acceptance Criteria--Method 604
----------------------------------------------------------------------------------------------------------------
                                                                      Test
                                                                     conc.   Limit for  Range for X   Range for
                             Parameter                              ([mu]g/  s ([mu]g/   ([mu]g/L)      P, Ps
                                                                       L)        L)                   (percent)
----------------------------------------------------------------------------------------------------------------
4-Chloro-3-methylphenol...........................................      100       16.6   56.7-113.4       49-122
2-Chlorophenol....................................................      100       27.0   54.1-110.2       38-126
2,4-Dichlorophenol................................................      100       25.1   59.7-103.3       44-119
2,4-Dimethylphenol................................................      100       33.3   50.4-100.0       24-118
4,6-Dinitro-2-methylphenol........................................      100       25.0   42.4-123.6       30-136
2,4-Dinitrophenol.................................................      100       36.0   31.7-125.1       12-145
2-Nitrophenol.....................................................      100       22.5   56.6-103.8       43-117
4-Nitrophenol.....................................................      100       19.0   22.7-100.0       13-110
Pentachlorophenol.................................................      100       32.4   56.7-113.5       36-134
Phenol............................................................      100       14.1   32.4-100.0       23-108
2,4,6-Trichlorophenol.............................................      100       16.6   60.8-110.4       53-119
----------------------------------------------------------------------------------------------------------------
s--Standard deviation of four recovery measurements, in [mu]g/L (Section 8.2.4).
X--Average recovery for four recovery measurements, in [mu]g/L (Section 8.2.4).
P, Ps--Percent recovery measured (Section 8.3.2, Section 8.4.2).
 
Note: These criteria are based directly upon the method performance data in Table 4. Where necessary, the limits
  for recovery have been broadened to assure applicability of the limits to concentrations below those used to
  develop Table 4.


                Table 4--Method Accuracy and Precision as Functions of Concentration--Method 604
----------------------------------------------------------------------------------------------------------------
                                                            Accuracy, as      Single Analyst        Overall
                       Parameter                            recovery, X'      precision, sr'     precision, S'
                                                             ([mu]g/L)          ([mu]g/L)          ([mu]g/L)
----------------------------------------------------------------------------------------------------------------
4-Chloro-3-methylphenol................................         0.87C-1.97         0.11X-0.21         0.16X+1.41
2-Chlorophenol.........................................         0.83C-0.84         0.18X+0.20         0.21X+0.75
2,4-Dichlorophenol.....................................         0.81C+0.48         0.17X-0.02         0.18X+0.62
2,4-Dimethylphenol.....................................         0.62C-1.64         0.30X-0.89         0.25X+0.48
4,6-Dinitro-2-methylphenol.............................         0.84C-1.01         0.15X+1.25         0.19X+5.85
2,4-Dinitrophenol......................................         0.80C-1.58         0.27X-1.15         0.29X+4.51
2-Nitrophenol..........................................         0.81C-0.76         0.15X+0.44         0.14X+3.84
4-Nitrophenol..........................................         0.46C+0.18         0.17X+2.43         0.19X+4.79
Pentachlorophenol......................................         0.83C+2.07         0.22X-0.58         0.23X+0.57
Phenol.................................................         0.43C+0.11         0.20X-0.88         0.17X+0.77
2,4,6-Trichlorophenol..................................         0.86C-0.40         0.10X+0.53         0.13X+2.40
----------------------------------------------------------------------------------------------------------------
X'=Expected recovery for one or more measurements of a sample containing a concentration of C, in [mu]g/L.
sr'=Expected single analyst standard deviation of measurements at an average concentration found of X, in [mu]g/
  L.
S'=Expected interlaboratory standard deviation of measurements at an average concentration found of X, in [mu]g/
  L.
C=True value for the concentration, in [mu]g/L.
X=Average recovery found for measurements of samples containing a concentration of C, in [mu]g/L.


[[Page 78]]

[GRAPHIC] [TIFF OMITTED] TC02JY92.012


[[Page 79]]

[GRAPHIC] [TIFF OMITTED] TC02JY92.013

                         Method 605--Benzidines

                        1. Scope and Application

    1.1  This method covers the determination of certain benzidines. The 
following parameters can be determined by this method:

------------------------------------------------------------------------
                   Parameter                     Storet No     CAS No.
------------------------------------------------------------------------
Benzidine.....................................        39120      92-87-5
3,3'-Dichlorobenzidine........................        34631      91-94-1
------------------------------------------------------------------------

    1.2  This is a high performance liquid chromatography (HPLC) method 
applicable to the determination of the compounds listed above in 
municipal and industrial discharges as provided under 40 CFR 136.1. When 
this method is used to analyze unfamiliar samples for the compounds 
above, identifications should be supported by at least one additional 
qualitative technique. This method describes electrochemical conditions 
at a second potential which can be used to confirm measurements made 
with this method. Method 625 provides gas chromatograph/mass 
spectrometer (GC/MS) conditions appropriate for the qualitative and 
quantitative confirmation of results for the parameters listed above, 
using the extract produced by this method.
    1.3  The method detection limit (MDL, defined in Section 14.1) 
1 for each parameter is

[[Page 80]]

listed in Table 1. The MDL for a specific wastewater may differ from 
those listed, depending upon the nature of the interferences in the 
sample matrix.
    1.4  Any modification of this method, beyond those expressly 
permitted, shall be considered as a major modification subject to 
application and approval of alternate test procedures under 40 CFR 136.4 
and 136.5.
    1.5  This method is restricted to use by or under the supervision of 
analysts experienced in the use of HPLC instrumentation and in the 
interpretation of liquid chromatograms. Each analyst must demonstrate 
the ability to generate acceptable results with this method using the 
procedure described in Section 8.2.

                          2. Summary of Method

    2.1  A measured volume of sample, approximately 1-L, is extracted 
with chloroform using liquid-liquid extractions in a separatory funnel. 
The chloroform extract is extracted with acid. The acid extract is then 
neutralized and extracted with chloroform. The final chloroform extract 
is exchanged to methanol while being concentrated using a rotary 
evaporator. The extract is mixed with buffer and separated by HPLC. The 
benzidine compounds are measured with an electrochemical 
detector.2
    2.2  The acid back-extraction acts as a general purpose cleanup to 
aid in the elimination of interferences.

                            3. Interferences

    3.1  Method interferences may be caused by contaminants in solvents, 
reagents, glassware, and other sample processing hardware that lead to 
discrete artifacts and/or elevated baselines in chromatograms. All of 
these materials must be routinely demonstrated to be free from 
interferences under the conditions of the analysis by running laboratory 
reagent blanks as described in Section 8.1.3.
    3.1.1  Glassware must be scrupulously cleaned.3 Clean all 
glassware as soon as possible after use by rinsing with the last solvent 
used in it. Solvent rinsing should be followed by detergent washing with 
hot water, and rinses with tap water and distilled water. The glassware 
should then be drained dry, and heated in a muffle furnace at 400  deg.C 
for 15 to 30 min. Some thermally stable materials may not be eliminated 
by this treatment. Solvent rinses with acetone and pesticide quality 
hexane may be substituted for the muffle furnace heating. Volumetric 
ware should not be heated in a muffle furnace. After drying and cooling, 
glassware should be sealed and stored in a clean environment to prevent 
any accumulation of dust or other contaminants. Store inverted or capped 
with aluminum foil.
    3.1.2  The use of high purity reagents and solvents helps to 
minimize interference problems. Purification of solvents by distillation 
in all-glass systems may be required.
    3.2  Matrix interferences may be caused by contaminants that are co-
extracted from the sample. The extent of matrix interferences will vary 
considerably from source to source, depending upon the nature and 
diversity of the industrial complex or municipality being sampled. The 
cleanup procedures that are inherent in the extraction step are used to 
overcome many of these interferences, but unique samples may require 
additional cleanup approaches to achieve the MDL listed in Table 1.
    3.3  Some dye plant effluents contain large amounts of components 
with retention times closed to benzidine. In these cases, it has been 
found useful to reduce the electrode potential in order to eliminate 
interferences and still detect benzidine. (See Section 12.7.)

                                4. Safety

    4.1  The toxicity or carcinogenicity of each reagent used in this 
method has not been precisely defined; however, each chemical compound 
should be treated as a potential health harzard. From this viewpoint, 
exposure to these chemicals must be reduced to the lowest possible level 
by whatever means available. The laboratory is responsible for 
maintaining a current awareness file of OSHA regulations regarding the 
safe handling of the chemicals specified in this method. A reference 
file of material data handling sheets should also be made available to 
all personnel involved in the chemical analysis. Additional references 
to laboratory safety are available and have been identified 
4-6 for the information of the analyst.
    4.2  The following parameters covered by this method have been 
tentatively classified as known or suspected, human or mammalian 
carcinogens: benzidine and 3,3'-dichlorobenzidine. Primary standards of 
these toxic compounds should be prepared in a hood. A NIOSH/MESA 
approved toxic gas respirator should be worn when the analyst handles 
high concentrations of these toxic compounds.
    4.3  Exposure to chloroform should be minimized by performing all 
extractions and extract concentrations in a hood or other well-
ventiliated area.

                       5. Apparatus and Materials

    5.1  Sampling equipment, for discrete or composite sampling.
    5.1.1  Grab sample bottle--1-L or 1-qt, amber glass, fitted with a 
screw cap lined with Teflon. Foil may be substituted for Teflon if the 
sample is not corrosive. If amber bottles are not available, protect 
samples from light. The bottle and cap liner must be washed, rinsed with 
acetone or methylene

[[Page 81]]

chloride, and dried before use to minimize contamination.
    5.1.2  Automatic sampler (optional)--The sampler must incorporate 
glass sample containers for the collection of a minimum of 250 mL of 
sample. Sample containers must be kept refrigerated at 4 deg.C and 
protected from light during compositing. If the sampler uses a 
peristaltic pump, a minimum length of compressible silicone rubber 
tubing may be used. Before use, however, the compressible tubing should 
be thoroughly rinsed with methanol, followed by repeated rinsings with 
distilled water to minimize the potential for contamination of the 
sample. An integrating flow meter is required to collect flow 
proportional composites.
    5.2  Glassware (All specifications are suggested):
    5.2.1  Separatory funnels--2000, 1000, and 250-mL, with Teflon 
stopcock.
    5.2.2  Vials--10 to 15-mL, amber glass, with Teflon-lined screw cap.
    5.2.3  Rotary evaporator.
    5.2.4  Flasks--Round bottom, 100-mL, with 24/40 joints.
    5.2.5  Centrifuge tubes--Conical, graduated, with Teflon-lined screw 
caps.
    5.2.6  Pipettes--Pasteur, with bulbs.
    5.3  Balance--Analytical, capable of accurately weighing 0.0001 g.
    5.4  High performance liquid chromatograph (HPLC)--An analytical 
system complete with column supplies, high pressure syringes, detector, 
and compatible recorder. A data system is recommended for measuring peak 
areas and retention times.
    5.4.1  Solvent delivery system--With pulse damper, Altex 110A or 
equivalent.
    5.4.2  Injection valve (optional)--Waters U6K or equivalent.
    5.4.3  Electrochemical detector--Bioanalytical Systems LC-2A with 
glassy carbon electrode, or equivalent. This detector has proven 
effective in the analysis of wastewaters for the parameters listed in 
the scope (Section 1.1), and was used to develop the method performance 
statements in Section 14. Guidelines for the use of alternate detectors 
are provided in Section 12.1.
    5.4.4  Electrode polishing kit--Princeton Applied Research Model 
9320 or equivalent.
    5.4.5  Column--Lichrosorb RP-2, 5 micron particle diameter, in a 25 
cm x 4.6 mm ID stainless steel column. This column was used to develop 
the method performance statements in Section 14. Guidelines for the use 
of alternate column packings are provided in Section 12.1.

                               6. Reagents

    6.1  Reagent water--Reagent water is defined as a water in which an 
interferent is not observed at the MDL of the parameters of interest.
    6.2  Sodium hydroxide solution (5 N)--Dissolve 20 g of NaOH (ACS) in 
reagent water and dilute to 100 mL.
    6.3  Sodium hydroxide solution (1 M)--Dissolve 40 g of NaOH (ACS) in 
reagent water and dilute to 1 L.
    6.4  Sodium thiosulfate--(ACS) Granular.
    6.5  Sodium tribasic phosphate (0.4 M)--Dissolve 160 g of trisodium 
phosphate decahydrate (ACS) in reagent water and dilute to 1 L.
    6.6  Sulfuric acid (1+1)--Slowly, add 50 mL of 
H2SO4 (ACS, sp. gr. 1.84) to 50 mL of reagent 
water.
    6.7  Sulfuric acid (1 M)--Slowly, add 58 mL of 
H2SO4 (ACS, sp. gr. 1.84) to reagent water and 
dilute to 1 L.
    6.8  Acetate buffer (0.1 M, pH 4.7)--Dissolve 5.8 mL of glacial 
acetic acid (ACS) and 13.6 g of sodium acetate trihydrate (ACS) in 
reagent water which has been purified by filtration through a RO-4 
Millipore System or equivalent and dilute to 1 L.
    6.9  Acetonitrile, chloroform (preserved with 1% ethanol), methanol-
-Pesticide quality or equivalent.
    6.10  Mobile phase--Place equal volumes of filtered acetonitrile 
(Millipore type FH filter or equivalent) and filtered acetate buffer 
(Millipore type GS filter or equivalent) in a narrow-mouth, glass 
container and mix thoroughly. Prepare fresh weekly. Degas daily by 
sonicating under vacuum, by heating an stirring, or by purging with 
helium.
    6.11  Stock standard solutions (1.00 [mu]g/[mu]L)--Stock standard 
solutions may be prepared from pure standard materials or purchased as 
certified solutions.
    6.11.1  Prepare stock standard solutions by accurately weighing 
about 0.0100 g of pure material. Dissolve the material in methanol and 
dilute to volume in a 10-mL volumetric flask. Larger volumes can be used 
at the convenience of the analyst. When compound purity is assayed to be 
96% or greater, the weight can be used without correction to calculate 
the concentration of the stock standard. Commercially prepared stock 
standards can be used at any concentration if they are certified by the 
manufacturer or by an independent source.
    6.11.2  Transfer the stock standard solutions into Teflon-sealed 
screw-cap bottles. Store at 4  deg.C and protect from light. Stock 
standard solutions should be checked frequently for signs of degradation 
or evaporation, especially just prior to preparing calibration standards 
from them.
    6.11.3  Stock standard solutions must be replaced after six months, 
or sooner if comparison with check standards indicates a problem.
    6.12  Quality control check sample concentrate--See Section 8.2.1.

[[Page 82]]

                             7. Calibration

    7.1  Establish chromatographic operating conditions equivalent to 
those given in Table 1. The HPLC system can be calibrated using the 
external standard technique (Section 7.2) or the internal standard 
technique (Section 7.3).
    7.2  External standard calibration procedure:
    7.2.1  Prepare calibration standards at a minimum of three 
concentration levels for each parameter of interest by adding volumes of 
one or more stock standards to a volumetric flask and diluting to volume 
with mobile phase. One of the external standards should be at a 
concentration near, but above, the MDL (Table 1) and the other 
concentrations should correspond to the expected range of concentrations 
found in real samples or should define the working range of the 
detector.
    7.2.2  Using syringe injections of 5 to 25 [mu]L or a constant 
volume injection loop, analyze each calibration standard according to 
Section 12 and tabulate peak height or area responses against the mass 
injected. The results can be used to prepare a calibration curve for 
each compound. Alternatively, if the ratio of response to amount 
injected (calibration factor) is a constant over the working range (<10% 
relative standard deviation, RSD), linearity through the origin can be 
assumed and the average ratio or calibration factor can be used in place 
of a calibration curve.
    7.3  Internal standard calibration procedure--To use this approach, 
the analyst must select one or more internal standards that are similar 
in analytical behavior to the compounds of interest. The analyst must 
further demonstrate that the measurement of the internal standard is not 
affected by method or matrix interferences. Because of these 
limitations, no internal standard can be suggested that is applicable to 
all samples.
    7.3.1  Prepare calibration standards at a minimum of three 
concentration levels for each parameter of interest by adding volumes of 
one or more stock standards to a volumetric flask. To each calibration 
standard, add a known constant amount of one or more internal standards, 
and dilute to volume with mobile phase. One of the standards should be 
at a concentration near, but above, the MDL and the other concentrations 
should correspond to the expected range of concentrations found in real 
samples or should define the working range of the detector.
    7.3.2  Using syringe injections of 5 to 25 [mu]L or a constant 
volume injection loop, analyze each calibration standard according to 
Section 12 and tabulate peak height or area responses against 
concentration for each compound and internal standard. Calculate 
response factors (RF) for each compound using Equation 1.

 
                                                                   RF=      (As)(Cis)    (Ais)(Cs)
----------------------------------------------------------------------------------------------------------------
 

                                                              Equation 1

where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Cis=Concentration of the internal standard ([mu]g/L).
Cs=Concentration of the parameter to be measured ([mu]g/L).

    If the RF value over the working range is a constant (<10% RSD), the 
RF can be assumed to be invariant and the average RF can be used for 
calculations. Alternatively, the results can be used to plot a 
calibration curve of response ratios, As/Ais, vs. 
RF.
    7.4  The working calibration curve, calibration factor, or RF must 
be verified on each working day by the measurement of one or more 
calibration standards. If the response for any parameter varies from the 
predicted response by more than 15%, a new calibration curve 
must be prepared for that compound. If serious loss of response occurs, 
polish the electrode and recalibrate.
    7.5  Before using any cleanup procedure, the analyst must process a 
series of calibration standards through the procedure to validate 
elution patterns and the absence of interferences from the reagents.

                           8. Quality Control

    8.1  Each laboratory that uses this method is required to operate a 
formal quality control program. The minimum requirements of this program 
consist of an initial demonstration of laboratory capability and an 
ongoing analysis of spiked samples to evaluate and document data 
quality. The laboratory must maintain records to document the quality of 
data that is generated. Ongoing data quality checks are compared with 
established performance criteria to determine if the results of analyses 
meet the performance characteristics of the method. When results of 
sample spikes indicate atypical method performance, a quality control 
check standard must be analyzed to confirm that the measurements were 
performed in an in-control mode of operation.
    8.1.1  The analyst must make an initial, one-time, demonstration of 
the ability to generate acceptable accuracy and precision with this 
method. This ability is established as described in Section 8.2.
    8.1.2  In recognition of advances that are occurring in 
chromatography, the analyst is permitted certain options (detailed in 
Sections 10.9, 11.1, and 12.1) to improve the separations or lower the 
cost of measurements. Each time such a modification is made to

[[Page 83]]

the method, the analyst is required to repeat the procedure in Section 
8.2.
    8.1.3  Before processing any samples, the analyst must analyze a 
reagent water blank to demonstrate that interferences from the 
analytical system and glassware are under control. Each time a set of 
samples is extracted or reagents are changed, a reagent water blank must 
be processed as a safeguard against laboratory contamination.
    8.1.4  The laboratory must, on an ongoing basis, spike and analyze a 
minimum of 10% of all samples to monitor and evaluate laboratory data 
quality. This procedure is described in Section 8.3.
    8.1.5  The laboratory must, on an ongoing basis, demonstrate through 
the analyses of quality control check standards that the operation of 
the measurement system is in control. This procedure is described in 
Section 8.4. The frequency of the check standard analyses is equivalent 
to 10% of all samples analyzed but may be reduced if spike recoveries 
from samples (Section 8.3) meet all specified quality control criteria.
    8.1.6  The laboratory must maintain performance records to document 
the quality of data that is generated. This procedure is described in 
Section 8.5.
    8.2  To establish the ability to generate acceptable accuracy and 
precision, the analyst must perform the following operations.
    8.2.1  A quality control (QC) check sample concentrate is required 
containing benzidine and/or 3,3'-dichlorobenzidine at a concentration of 
50 [mu]g/mL each in methanol. The QC check sample concentrate must be 
obtained from the U.S. Environmental Protection Agency, Environmental 
Monitoring and Support Laboratory in Cincinnati, Ohio, if available. If 
not available from that source, the QC check sample concentrate must be 
obtained from another external source. If not available from either 
source above, the QC check sample concentrate must be prepared by the 
laboratory using stock standards prepared independently from those used 
for calibration.
    8.2.2  Using a pipet, prepare QC check samples at a concentration of 
50 [mu]g/L by adding 1.00 mL of QC check sample concentrate to each of 
four 1-L-L aliquots of reagent water.
    8.2.3  Analyze the well-mixed QC check samples according to the 
method beginning in Section 10.
    8.2.4  Calculate the average recovery (X) in [mu]g/L, and the 
standard deviation of the recovery (s) in [mu]g/L, for each parameter 
using the four results.
    8.2.5  For each parameter compare s and X with the corresponding 
acceptance criteria for precision and accuracy, respectively, found in 
Table 2. If s and X for all parameters of interest meet the acceptance 
criteria, the system performance is acceptable and analysis of actual 
samples can begin. If any individual s exceeds the precision limit or 
any individual X falls outside the range for accuracy, the system 
performance is unacceptable for that parameter. Locate and correct the 
source of the problem and repeat the test for all parameters of interest 
beginning with Section 8.2.2.
    8.3  The laboratory must, on an ongoing basis, spike at least 10% of 
the samples from each sample site being monitored to assess accuracy. 
For laboratories analyzing one to ten samples per month, at least one 
spiked sample per month is required.
    8.3.1  The concentration of the spike in the sample should be 
determined as follows:
    8.3.1.1  If, as in compliance monitoring, the concentration of a 
specific parameter in the sample is being checked against a regulatory 
concentration limit, the spike should be at that limit or 1 to 5 times 
higher than the background concentration determined in Section 8.3.2, 
whichever concentration would be larger.
    8.3.1.2  If the concentration of a specific parameter in the sample 
is not being checked against a limit specific to that parameter, the 
spike should be at 50 [mu]g/L or 1 to 5 times higher than the background 
concentration determined in Section 8.3.2, whichever concentration would 
be larger.
    8.3.1.3  If it is impractical to determine background levels before 
spiking (e.g., maximum holding times will be exceeded), the spike 
concentration should be (1) the regulatory concentration limit, if any; 
or, if none (2) the larger of either 5 times higher than the expected 
background concentration or 50 [mu]g/L.
    8.3.2  Analyze one sample aliquot to determine the background 
concentration (B) of each parameter. If necessary, prepare a new QC 
check sample concentrate (Section 8.2.1) appropriate for the background 
concentrations in the sample. Spike a second sample aliquot with 1.0 mL 
of the QC check sample concentrate and analyze it to determine the 
concentration after spiking (A) of each parameter. Calculate each 
percent recovery (P) as 100(A-B)%/T, where T is the known true value of 
the spike.
    8.3.3  Compare the percent recovery (P) for each parameter with the 
corresponding QC acceptance criteria found in Table 2. These acceptance 
criteria were calculated to include an allowance for error in 
measurement of both the background and spike concentrations, assuming a 
spike to background ratio of 5:1. This error will be accounted for to 
the extent that the analyst's spike to background ratio approaches 
5:1.\7\ If spiking was performed at a concentration lower than 50 [mu]g/
L, the analyst must use either the QC acceptance criteria in Table 2, or 
optional QC acceptance criteria calculated for the specific spike 
concentration. To calculate optional acceptance criteria for the 
recovery of a parameter: (1) Calculate accuracy (X') using the equation 
in Table 3, substituting

[[Page 84]]

the spike concentration (T) for C; (2) calculate overall precision (S') 
using the equation in Table 3, substituting X' for X; (3) calculate the 
range for recovery at the spike concentration as (100 X'/
T)2.44(100 S'/T)%.\7\
    8.3.4  If any individual P falls outside the designated range for 
recovery, that parameter has failed the acceptance criteria. A check 
standard containing each parameter that failed the criteria must be 
analyzed as described in Section 8.4.
    8.4  If any parameter fails the acceptance criteria for recovery in 
Section 8.3, a QC check standard containing each parameter that failed 
must be prepared and analyzed.
    Note: The frequency for the required analysis of a QC check standard 
will depend upon the number of parameters being simultaneously tested, 
the complexity of the sample matrix, and the performance of the 
laboratory.
    8.4.1  Prepare the QC check standard by adding 1.0 mL of QC check 
sample concentrate (Sections 8.2.1 or 8.3.2) to 1 L of reagent water. 
The QC check standard needs only to contain the parameters that failed 
criteria in the test in Section 8.3.
    8.4.2  Analyze the QC check standard to determine the concentration 
measured (A) of each parameter. Calculate each percent recovery 
(Ps) as 100 (A/T)%, where T is the true value of the standard 
concentration.
    8.4.3  Compare the percent recovery (Ps) for each 
parameter with the corresponding QC acceptance criteria found in Table 
2. Only parameters that failed the test in Section 8.3 need to be 
compared with these criteria. If the recovery of any such parameter 
falls outside the designated range, the laboratory performance for that 
parameter is judged to be out of control, and the problem must be 
immediately identified and corrected. The analytical result for that 
parameter in the unspiked sample is suspect and may not be reported for 
regulatory compliance purposes.
    8.5  As part of the QC program for the laboratory, method accuracy 
for wastewater samples must be assessed and records must be maintained. 
After the analysis of five spiked wastewater samples as in Section 8.3, 
calculate the average percent recovery (P) and the standard deviation of 
the percent recovery (sp). Express the accuracy assessment as 
a percent recovery interval from P-2sp to P+2sp. 
If P=90% and sp=10%, for example, the accuracy interval is 
expressed as 70-110%. Update the accuracy assessment for each parameter 
on a regular basis (e.g. after each five to ten new accuracy 
measurements).
    8.6  It is recommended that the laboratory adopt additional quality 
assurance practices for use with this method. The specific practices 
that are most productive depend upon the needs of the laboratory and the 
nature of the samples. Field duplicates may be analyzed to assess the 
precision of the environmental measurements. When doubt exists over the 
identification of a peak on the chromatogram, confirmatory techniques 
such as HPLC with a dissimilar column, gas chromatography, or mass 
spectrometer must be used. Whenever possible, the laboratory should 
analyze standard reference materials and participate in relevant 
performance evaluation studies.

            9. Sample Collection, Preservation, and Handling

    9.1  Grab samples must be collected in glass containers. 
Conventional sampling practices\8\ should be followed, except that the 
bottle must not be prerinsed with sample before collection. Composite 
samples should be collected in refrigerated glass containers in 
accordance with the requirements of the program. Automatic sampling 
equipment must be as free as possible of Tygon tubing and other 
potential sources of contamination.
    9.2  All samples must be iced or refrigerated at 4 deg.C and stored 
in the dark from the time of collection until extraction. Both benzidine 
and 3,3'-dichlorobenzidine are easily oxidized. Fill the sample bottles 
and, if residual chlorine is present, add 80 mg of sodium thiosulfate 
per liter of sample and mix well. EPA Methods 330.4 and 330.5 may be 
used for measurement of residual chlorine.\9\ Field test kits are 
available for this purpose. After mixing, adjust the pH of the sample to 
a range of 2 to 7 with sulfuric acid.
    9.3  If 1,2-diphenylhydrazine is likely to be present, adjust the pH 
of the sample to 4.0 0.2 to prevent rearrangement to 
benzidine.
    9.4  All samples must be extracted within 7 days of collection. 
Extracts may be held up to 7 days before analysis, if stored under an 
inert (oxidant free) atmosphere.\2\ The extract should be protected from 
light.

                          10. Sample Extraction

    10.1  Mark the water meniscus on the side of the sample bottle for 
later determination of sample volume. Pour the entire sample into a 2-L 
separatory funnel. Check the pH of the sample with wide-range pH paper 
and adjust to within the range of 6.5 to 7.5 with sodium hydroxide 
solution or sulfuric acid.
    10.2  Add 100 mL of chloroform to the sample bottle, seal, and shake 
30 s to rinse the inner surface. (Caution: Handle chloroform in a well 
ventilated area.) Transfer the solvent to the separatory funnel and 
extract the sample by shaking the funnel for 2 min with periodic venting 
to release excess pressure. Allow the organic layer to separate from the 
water phase for a minimum of 10 min. If the emulsion interface between 
layers is more than one-third the volume of the solvent layer, the 
analyst must employ mechanical techniques to complete the phase 
separation. The optimum technique depends upon the sample, but may 
include stirring, filtration of the emulsion through glass

[[Page 85]]

wool, centrifugation, or other physical methods. Collect the chloroform 
extract in a 250-mL separatory funnel.
    10.3  Add a 50-mL volume of chloroform to the sample bottle and 
repeat the extraction procedure a second time, combining the extracts in 
the separatory funnel. Perform a third extraction in the same manner.
    10.4  Separate and discard any aqueous layer remaining in the 250-mL 
separatory funnel after combining the organic extracts. Add 25 mL of 1 M 
sulfuric acid and extract the sample by shaking the funnel for 2 min. 
Transfer the aqueous layer to a 250-mL beaker. Extract with two 
additional 25-mL portions of 1 M sulfuric acid and combine the acid 
extracts in the beaker.
    10.5  Place a stirbar in the 250-mL beaker and stir the acid extract 
while carefully adding 5 mL of 0.4 M sodium tribasic phosphate. While 
monitoring with a pH meter, neutralize the extract to a pH between 6 and 
7 by dropwise addition of 5 N sodium hydroxide solution while stirring 
the solution vigorously. Approximately 25 to 30 mL of 5 N sodium 
hydroxide solution will be required and it should be added over at least 
a 2-min period. Do not allow the sample pH to exceed 8.
    10.6  Transfer the neutralized extract into a 250-mL separatory 
funnel. Add 30 mL of chloroform and shake the funnel for 2 min. Allow 
the phases to separate, and transfer the organic layer to a second 250-
mL separatory funnel.
    10.7  Extract the aqueous layer with two additional 20-mL aliquots 
of chloroform as before. Combine the extracts in the 250-mL separatory 
funnel.
    10.8  Add 20 mL of reagent water to the combined organic layers and 
shake for 30 s.
    10.9  Transfer the organic extract into a 100-mL round bottom flask. 
Add 20 mL of methanol and concentrate to 5 mL with a rotary evaporator 
at reduced pressure and 35  deg.C. An aspirator is recommended for use 
as the source of vacuum. Chill the receiver with ice. This operation 
requires approximately 10 min. Other concentration techniques may be 
used if the requirements of Section 8.2 are met.
    10.10  Using a 9-in. Pasteur pipette, transfer the extract to a 15-
mL, conical, screw-cap centrifuge tube. Rinse the flask, including the 
entire side wall, with 2-mL portions of methanol and combine with the 
original extract.
    10.11  Carefully concentrate the extract to 0.5 mL using a gentle 
stream of nitrogen while heating in a 30  deg.C water bath. Dilute to 2 
mL with methanol, reconcentrate to 1 mL, and dilute to 5 mL with acetate 
buffer. Mix the extract thoroughly. Cap the centrifuge tube and store 
refrigerated and protected from light if further processing will not be 
performed immediately. If the extract will be stored longer than two 
days, it should be transferred to a Teflon-sealed screw-cap vial. If the 
sample extract requires no further cleanup, proceed with HPLC analysis 
(Section 12). If the sample requires further cleanup, proceed to Section 
11.
    10.12  Determine the original sample volume by refilling the sample 
bottle to the mark and transferring the liquid to a 1,000-mL graduated 
cylinder. Record the sample volume to the nearest 5 mL.

                       11. Cleanup and Separation

    11.1  Cleanup procedures may not be necessary for a relatively clean 
sample matrix. If particular circumstances demand the use of a cleanup 
procedure, the analyst first must demonstrate that the requirements of 
Section 8.2 can be met using the method as revised to incorporate the 
cleanup procedure.

               12. High Performance Liquid Chromatography

    12.1  Table 1 summarizes the recommended operating conditions for 
the HPLC. Included in this table are retention times, capacity factors, 
and MDL that can be achieved under these conditions. An example of the 
separations achieved by this HPLC column is shown in Figure 1. Other 
HPLC columns, chromatographic conditions, or detectors may be used if 
the requirements of Section 8.2 are met. When the HPLC is idle, it is 
advisable to maintain a 0.1 mL/min flow through the column to prolong 
column life.
    12.2  Calibrate the system daily as described in Section 7.
    12.3  If the internal standard calibration procedure is being used, 
the internal standard must be added to the sample extract and mixed 
thoroughly immediately before injection into the instrument.
    12.4  Inject 5 to 25 [mu]L of the sample extract or standard into 
the HPLC. If constant volume injection loops are not used, record the 
volume injected to the nearest 0.05 [mu]L, and the resulting peak size 
in area or peak height units.
    12.5  Identify the parameters in the sample by comparing the 
retention times of the peaks in the sample chromatogram with those of 
the peaks in standard chromatograms. The width of the retention time 
window used to make identifications should be based upon measurements of 
actual retention time variations of standards over the course of a day. 
Three times the standard deviation of a retention time for a compound 
can be used to calculate a suggested window size; however, the 
experience of the analyst should weigh heavily in the interpretation of 
chromatograms.
    12.6  If the response for a peak exceeds the working range of the 
system, dilute the extract with mobile phase and reanalyze.
    12.7  If the measurement of the peak response for benzidine is 
prevented by the presence of interferences, reduce the electrode

[[Page 86]]

potential to +0.6 V and reanalyze. If the benzidine peak is still 
obscured by interferences, further cleanup is required.

                            13. Calculations

    13.1  Determine the concentration of individual compounds in the 
sample.
    13.1.1  If the external standard calibration procedure is used, 
calculate the amount of material injected from the peak response using 
the calibration curve or calibration factor determined in Section 7.2.2. 
The concentration in the sample can be calculated from Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.101

                                                              Equation 2

where:
A=Amount of material injected (ng).
Vi=Volume of extract injected ([mu]L).
Vt=Volume of total extract ([mu]L).
Vs=Volume of water extracted (mL).

    13.1.2  If the internal standard calibration procedure is used, 
calculate the concentration in the sample using the response factor (RF) 
determined in Section 7.3.2 and Equation 3.
[GRAPHIC] [TIFF OMITTED] TC15NO91.102

                                                              Equation 3

where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Is=Amount of internal standard added to each extract ([mu]g).
Vo=Volume of water extracted (L).

    13.2  Report results in [mu]g/L without correction for recovery 
data. All QC data obtained should be reported with the sample results.

                         14. Method Performance

    14.1  The method detection limit (MDL) is defined as the minimum 
concentration of a substance that can be measured and reported with 99% 
confidence that the value is above zero.\1\ The MDL concentrations 
listed in Table 1 were obtained using reagent water.\10\ Similar results 
were achieved using representative wastewaters. The MDL actually 
achieved in a given analysis will vary depending on instrument 
sensitivity and matrix effects.
    14.2  This method has been tested for linearity of spike recovery 
from reagent water and has been demonstrated to be applicable over the 
concentration range from 7xMDL to 3000xMDL.\10\
    14.3  This method was tested by 17 laboratories using reagent water, 
drinking water, surface water, and three industrial wastewaters spiked 
at six concentrations over the range 1.0 to 70 [mu]g/L.\11\ Single 
operator precision, overall precision, and method accuracy were found to 
be directly related to the concentration of the parameter and 
essentially independent of the sample matrix. Linear equations to 
describe these relationships are presented in Table 3.

                               References

    1. 40 CFR part 136, appendix B.
    2. ``Determination of Benzidines in Industrial and Muncipal 
Wastewaters,'' EPA 600/4-82-022, National Technical Information Service, 
PB82-196320, Springfield, Virginia 22161, April 1982.
    3. ASTM Annual Book of Standards, Part 31, D3694-78. ``Standard 
Practices for Preparation of Sample Containers and for Preservation of 
Organic Constituents,'' American Society for Testing and Materials, 
Philadelphia.
    4. ``Carcinogens--Working With Carcinogens,'' Department of Health, 
Education, and Welfare, Public Health Service, Center for Disease 
Control, National Institute for Occupational Safety and Health, 
Publication No. 77-206, August 1977.
    5. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR 
part 1910), Occupational Safety and Health Administration, OSHA 2206 
(Revised, January 1976).
    6. ``Safety in Academic Chemistry Laboratories,'' American Chemical 
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
    7. Provost, L.P., and Elder, R.S. ``Interpretation of Percent 
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44 
used in the equation in Section 8.3.3 is two times the value 1.22 
derived in this report.)
    8. ASTM Annual Book of Standards, Part 31, D3370-76. ``Standard 
Practices for Sampling Water,'' American Society for Testing and 
Materials, Philadelphia.
    9. ``Methods 330.4 (Titrimetric, DPD-FAS) and 330.5 
(Spectrophotometric, DPD) for Chlorine Total Residual,'' Methods for 
Chemical Analysis of Water and Wastes, EPA-600/4-79-020, U.S. 
Environmental Protection Agency, Environmental Monitoring and Support 
Laboratory, Cincinnati, Ohio 45268, March 1979.
    10. ``EPA Method Study 15, Method 605 (Benzidines),'' EPA 600/4-84-
062, National Technical Information Service, PB84-211176, Springfield, 
Virginia 22161, June 1984.
    11. ``EPA Method Validation Study 15, Method 605 (Benzidines),'' 
Report for EPA Contract 68-03-2624 (In preparation).

[[Page 87]]



     Table 1--Chromatographic Conditions and Method Detection Limits
------------------------------------------------------------------------
                                                                Method
                                    Retention      Column     detection
            Parameter               time (min)    capacity      limit
                                                factor (k')   ([mu]g/L)
------------------------------------------------------------------------
Benzidine........................          6.1         1.44         0.08
3,3'-Dichlorobenzidine...........         12.1         3.84         0.13
------------------------------------------------------------------------
HPLC Column conditions: Lichrosorb RP-2, 5 micron particle size, in a 25
  cmx4.6 mm ID stainless steel column. Mobile Phase: 0.8 mL/min of 50%
  acetonitrile/50% 0.1M pH 4.7 acetate buffer. The MDL were determined
  using an electrochemical detector operated at +0.8 V.


                                   Table 2--QC Acceptance Criteria--Method 605
----------------------------------------------------------------------------------------------------------------
                                                                        Test    Limit for   Range for  Range for
                             Parameter                                 conc.    s ([mu]g/   X ([mu]g/    P, Ps
                                                                     ([mu]g/L)      L)         L)      (percent)
----------------------------------------------------------------------------------------------------------------
Benzidine..........................................................         50       18.7    9.1-61.0      D-140
3.3'-Dichlorobenzidine.............................................         50       23.6   18.7-50.0      5-128
----------------------------------------------------------------------------------------------------------------
s=Standard deviation of four recovery measurements, in [mu]g/L (Section 8.2.4).
X=Average recovery for four recovery measurements, in [mu]g/L (Section 8.2.4).
P, Ps=Percent recovery measured (Section 8.3.2, Section 8.4.2).
D=Detected; result must be greater than zero.
 
Note: These criteria are based directly upon the method performance data in Table 3. Where necessary, the limits
  for recovery have been broadened to assure applicability of the limits to concentrations below those used to
  develop Table 3.


                Table 3--Method Accuracy and Precision as Functions of Concentration--Method 605
----------------------------------------------------------------------------------------------------------------
                                                                   Accuracy, as   Single analyst      Overall
                            Parameter                                recovery,    precision, sr'   precision, S'
                                                                    X'([mu]g/L)      ([mu]g/L)       ([mu]g/L)
----------------------------------------------------------------------------------------------------------------
Benzidine.......................................................      0.70C+0.06      0.28X+0.19      0.40X+0.18
3,3'-Dichlorobenzidine..........................................      0.66C+0.23      0.39X-0.05      0.38X+0.02
----------------------------------------------------------------------------------------------------------------
X'=Expected recovery for one or more measurements of a sample containing a concentration of C, in [mu]g/L.
sr'=Expected single analyst standard deviation of measurements at an average concentration found of X, in [mu]g/
  L.
S'=Expected interlaboratory standard deviation of measurements at an average concentration found of X, in [mu]g/
  L.
C=True value for the concentration, in [mu]g/L.
X=Average recovery found for measurements of samples containing a concentration of C, in [mu]g/L.


[[Page 88]]

[GRAPHIC] [TIFF OMITTED] TC02JY92.014


[[Page 89]]

                       Method 606--Phthalate Ester

                        1. Scope and Application

    1.1  This method covers the determination of certain phthalate 
esters. The following parameters can be determined by this method:

------------------------------------------------------------------------
                                                      STORET
                     Parameter                         No.      CAS No.
------------------------------------------------------------------------
Bis(2-ethylhexyl) phthalate........................    39100    117-81-7
Butyl benzyl phthalate.............................    34292     85-68-7
Di-n-butyl phthalate...............................    39110     84-74-2
Diethyl phthalate..................................    34336     84-66-2
Dimethyl phthalate.................................    34341    131-11-3
Di-n-octyl phthalate...............................    34596    117-84-0
------------------------------------------------------------------------

    1.2  This is a gas chromatographic (GC) method applicable to the 
determination of the compounds listed above in municipal and industrial 
discharges as provided under 40 CFR 136.1. When this method is used to 
analyze unfamiliar samples for any or all of the compounds above, 
compound identifications should be supported by at least one additional 
qualitative technique. This method describes analytical conditions for a 
second gas chromatographic column that can be used to confirm 
measurements made with the primary column. Method 625 provides gas 
chromatograph/mass spectrometer (GC/MS) conditions appropriate for the 
qualitative and quantitative confirmation of results for all of the 
parameters listed above, using the extract produced by this method.
    1.3  The method detection limit (MDL, defined in Section 14.1)\1\ 
for each parameter is listed in Table 1. The MDL for a specific 
wastewater may differ from those listed, depending upon the nature of 
interferences in the sample matrix.
    1.4  The sample extraction and concentration steps in this method 
are essentially the same as in Methods 608, 609, 611, and 612. Thus, a 
single sample may be extracted to measure the parameters included in the 
scope of each of these methods. When cleanup is required, the 
concentration levels must be high enough to permit selecting aliquots, 
as necessary, to apply appropriate cleanup procedures. The analyst is 
allowed the latitude, under Section 12, to select chromatographic 
conditions appropriate for the simultaneous measurement of combinations 
of these parameters.
    1.5  Any modification of this method, beyond those expressly 
permitted, shall be considered as a major modification subject to 
application and approval of alternate test procedures under 40 CFR 136.4 
and 136.5.
    1.6  This method is restricted to use by or under the supervision of 
analysts experienced in the use of a gas chromatograph and in the 
interpretation of gas chromatograms. Each analyst must demonstrate the 
ability to generate acceptable results with this method using the 
procedure described in Section 8.2.

                          2. Summary of Method

    2.1  A measured volume of sample, approximately 1-L, is extracted 
with methylene chloride using a separatory funnel. The methylene 
chloride extract is dried and exchanged to hexane during concentration 
to a volume of 10 mL or less. The extract is separated by gas 
chromatography and the phthalate esters are then measured with an 
electron capture detector.\2\
    2.2  Analysis for phthalates is especially complicated by their 
ubiquitous occurrence in the environment. The method provides Florisil 
and alumina column cleanup procedures to aid in the elimination of 
interferences that may be encountered.

                            3. Interferences

    3.1  Method interferences may be caused by contaminants in solvents, 
reagents, glassware, and other sample processing hardware that lead to 
discrete artifacts and/or elevated baselines in gas chromatograms. All 
of these materials must be routinely demonstrated to be free from 
interferences under the conditions of the analysis by running laboratory 
reagent blanks as described in Section 8.1.3.
    3.1.1  Glassware must be scrupulously cleaned.\3\ Clean all 
glassware as soon as possible after use by rinsing with the last solvent 
used in it. Solvent rinsing should be followed by detergent washing with 
hot water, and rinses with tap water and distilled water. The glassware 
should then be drained dry, and heated in a muffle furnace at 400  deg.C 
for 15 to 30 min. Some thermally stable materials, such as PCBs, may not 
be eliminated by this treatment. Solvent rinses with acetone and 
pesticide quality hexane may be substituted for the muffle furnace 
heating. Thorough rinsing with such solvents usually eliminates PCB 
interference. Volumetric ware should not be heated in a muffle furnace. 
After drying and cooling, glassware should be sealed and stored in a 
clean environment to prevent any accumulation of dust or other 
contaminants. Store inverted or capped with aluminum foil.
    3.1.2  The use of high purity reagents and solvents helps to 
minimize interference problems. Purification of solvents by distillation 
in all-glass systems may be required.
    3.2  Phthalate esters are contaminants in many products commonly 
found in the laboratory. It is particularly important to avoid the use 
of plastics because phthalates are commonly used as plasticizers and are 
easily extracted from plastic materials. Serious phthalate contamination 
can result at any time, if consistent quality control is not practiced. 
Great care must be experienced to prevent such contamination. Exhaustive 
cleanup of reagents and glassware may be required to eliminate 
background phthalate contamination.4,5

[[Page 90]]

    3.3  Matrix interferences may be caused by contaminants that are co-
extracted from the sample. The extent of matrix interferences will vary 
considerably from source to source, depending upon the nature and 
diversity of the industrial complex or municipality being sampled. The 
cleanup procedures in Section 11 can be used to overcome many of these 
interferences, but unique samples may require additional cleanup 
approaches to achieve the MDL listed in Table 1.

                                4. Safety

    4.1  The toxicity or carcinogenicity of each reagent used in this 
method has not been precisely defined; however, each chemical compound 
should be treated as a potential health hazard. From this viewpoint, 
exposure to these chemicals must be reduced to the lowest possible level 
by whatever means available. The laboratory is responsible for 
maintaining a current awareness file of OSHA regulations regarding the 
safe handling of the chemicals specified in this method. A reference 
file of material data handling sheets should also be made available to 
all personnel involved in the chemical analysis. Additional references 
to laboratory safety are available and have been identified 
\6\-\8\ for the information of the analyst.

                       5. Apparatus and Materials

    5.1  Sampling equipment, for discrete or composite sampling.
    5.1.1  Grab sample bottle--1-L or 1-qt, amber glass, fitted with a 
screw cap lined with Teflon. Foil may be substituted for Teflon if the 
sample is not corrosive. If amber bottles are not available, protect 
samples from light. The bottle and cap liner must be washed, rinsed with 
acetone or methylene chloride, and dried before use to minimize 
contamination.
    5.1.2  Automatic sampler (optional)--The sampler must incorporate 
glass sample containers for the collection of a minimum of 250 mL of 
sample. Sample containers must be kept refrigerated at 4  deg.C and 
protected from light during compositing. If the sampler uses a 
peristaltic pump, a minimum length of compressible silicone rubber 
tubing may be used. Before use, however, the compressible tubing should 
be thoroughly rinsed with methanol, followed by repeated rinsings with 
distilled water to minimize the potential for contamination of the 
sample. An integrating flow meter is required to collect flow 
proportional composites.
    5.2  Glassware (All specifications are suggested. Catalog numbers 
are included for illustration only).
    5.2.1  Separatory funnel--2-L, with Teflon stopcock.
    5.2.2  Drying column--Chromatographic column, approximately 400 mm 
long x 19 mm ID, with coarse frit filter disc.
    5.2.3  Chromatographic column--300 mm long x 10 mm ID, with Teflon 
stopcock and coarse frit filter disc at bottom (Kontes K-420540-0213 or 
equivalent).
    5.2.4  Concentrator tube, Kuderna-Danish--10-mL, graduated (Kontes 
K-570050-1025 or equivalent). Calibration must be checked at the volumes 
employed in the test. Ground glass stopper is used to prevent 
evaporation of extracts.
    5.2.5  Evaporative flask, Kuderna-Danish--500-mL (Kontes K-570001-
0500 or equivalent). Attach to concentrator tube with springs.
    5.2.6  Snyder column, Kuderna-Danish--Three-ball macro (Kontes K-
503000-0121 or equivalent).
    5.2.7  Snyder column, Kuderna-Danish--Two-ball micro (Kontes K-
569001-0219 or equivalent).
    5.2.8  Vials--10 to 15-mL, amber glass, with Teflon-lined screw cap.
    5.3  Boiling chips--Approximately 10/40 mesh. Heat to 400  deg.C for 
30 min or Soxhlet extract with methylene chloride.
    5.4  Water bath--Heated, with concentric ring cover, capable of 
temperature control (2  deg.C). The bath should be used in a 
hood.
    5.5  Balance--Analytical, capable of accurately weighing 0.0001 g.
    5.6  Gas chromatograph--An analytical system complete with gas 
chromatograph suitable for on-column injection and all required 
accessories including syringes, analytical columns, gases, detector, and 
strip-chart recorder. A data system is recommended for measuring peak 
areas.
    5.6.1  Column 1--1.8 m long x 4 mm ID glass, packed with 1.5% SP-
2250/1.95% SP-2401 Supelcoport (100/120 mesh) or equivalent. This column 
was used to develop the method performance statemelts in Section 14. 
Guidelines for the use of alternate column packings are provided in 
Section 12.1.
    5.6.2  Column 2--1.8 m long x 4 mm ID glass, packed with 3% OV-1 on 
Supelcoport (100/120 mesh) or equivalent.
    5.6.3  Detector--Electron capture detector. This detector has proven 
effective in the analysis of wastewaters for the parameters listed in 
the scope (Section 1.1), and was used to develop the method performance 
statements in Section 14. Guidelines for the use of alternate detectors 
are provided in Section 12.1.

                               6. Reagents

    6.1  Reagent water--Reagent water is defined as a water in which an 
interferent is not observed at the MDL of the parameters of interest.
    6.2  Acetone, hexane, isooctane, methylene chloride, methanol--
Pesticide quality or equivalent.
    6.3  Ethyl ether--nanograde, redistilled in glass if necessary.
    6.3.1  Ethyl ether must be shown to be free of peroxides before it 
is used as indicated by

[[Page 91]]

EM Laboratories Quant test strips. (Available from Scientific Products 
Co., Cat. No. P1126-8, and other suppliers.)
    6.3.2  Procedures recommended for removal of peroxides are provided 
with the test strips. After cleanup, 20 mL of ethyl alcohol preservative 
must be added to each liter of ether.
    6.4  Sodium sulfate--(ACS) Granular, anhydrous. Several levels of 
purification may be required in order to reduce background phthalate 
levels to an acceptable level: 1) Heat 4 h at 400  deg.C in a shallow 
tray, 2) Heat 16 h at 450 to 500  deg.C in a shallow tray, 3) Soxhlet 
extract with methylene chloride for 48 h.
    6.5  Florisil--PR grade (60/100 mesh). Purchase activated at 1250 
deg.F and store in the dark in glass containers with ground glass 
stoppers or foil-lined screw caps. To prepare for use, place 100 g of 
Florisil into a 500-mL beaker and heat for approximately 16 h at 40 
deg.C. After heating transfer to a 500-mL reagent bottle. Tightly seal 
and cool to room temperature. When cool add 3 mL of reagent water. Mix 
thoroughly by shaking or rolling for 10 min and let it stand for at 
least 2 h. Keep the bottle sealed tightly.
    6.6  Alumina--Neutral activity Super I, W200 series (ICN Life 
Sciences Group, No. 404583). To prepare for use, place 100 g of alumina 
into a 500-mL beaker and heat for approximately 16 h at 400  deg.C. 
After heating transfer to a 500-mL reagent bottle. Tightly seal and cool 
to room temperature. When cool add 3 mL of reagent water. Mix thoroughly 
by shaking or rolling for 10 min and let it stand for at least 2 h. Keep 
the bottle sealed tightly.
    6.7  Stock standard solutions (1.00 [mu]g/[mu]L)--Stock standard 
solutions can be prepared from pure standard materials or purchased as 
certified solutions.
    6.7.1  Prepare stock standard solutions by accurately weighing about 
0.0100 g of pure material. Dissolve the material in isooctane and dilute 
to volume in a 10-mL volumetric flask. Larger volumes can be used at the 
convenience of the analyst. When compound purity is assayed to be 96% or 
greater, the weight can be used without correction to calculate the 
concentration of the stock standard. Commercially prepared stock 
standards can be used at any concentration if they are certified by the 
manufacturer or by an independent source.
    6.7.2  Transfer the stock standard solutions into Teflon-sealed 
screw-cap bottles. Store at 4  deg.C and protect from light. Stock 
standard solutions should be checked frequently for signs of degradation 
or evaporation, especially just prior to preparing calibration standards 
from them.
    6.7.3  Stock standard solutions must be replaced after six months, 
or sooner if comparison with check standards indicates a problem.
    6.8  Quality control check sample concentrate--See Section 8.2.1.

                             7. Calibration

    7.1  Establish gas chromatograph operating conditions equivalent to 
those given in Table 1. The gas chromatographic system can be calibrated 
using the external standard technique (Section 7.2) or the internal 
standard technique (Section 7.3).
    7.2  External standard calibration procedure:
    7.2.1  Prepared calibration standards at a minimum of three 
concentration levels for each parameter of interest by adding volumes of 
one or more stock standards to a volumetric flask and diluting to volume 
with isooctane. One of the external standards should be at a 
concentration near, but above, the MDL (Table 1) and the other 
concentrations should correspond to the expected range of concentrations 
found in real samples or should define the working range of the 
detector.
    7.2.2  Using injections of 2 to 5 [mu]L, analyze each calibration 
standard according to Section 12 and tabulate peak height or area 
responses against the mass injected. The results can be used to prepare 
a calibration curve for each compound. Alternatively, if the ratio of 
response to amount injected (calibration factor) is a constant over the 
working range (<10% relative standard deviation, RSD), linearity through 
the origin can be assumed and the average ratio or calibration factor 
can be used in place of a calibration curve.
    7.3  Internal standard calibration procedure--To use this approach, 
the analyst must select one or more internal standards that are similar 
in analytical behavior to the compounds of interest. The analyst must 
further demonstrate that the measurement of the internal standard is not 
affected by method or matrix interferences. Because of these 
limitations, no internal standard can be suggested that is applicable to 
all samples.
    7.3.1  Prepare calibration standards at a minimum of three 
concentration levels for each parameter of interest by adding volumes of 
one or more stock standards to a volumetric flash. To each calibration 
standard, add a known constant amount of one or more internal standards, 
and dilute to volume with isooctane. One of the standards should be at a 
concentraton near, but above, the MDL and the other concentrations 
should correspond to the expected range of concentrations found in real 
samples or should define the working range of the detector.

[[Page 92]]

    7.3.2  Using injections of 2 to 5 [mu]L, analyze each calibration 
standard according to Section 12 and tabulate peak height or area 
responses against concentration for each compound and internal standard. 
Calculate response factors (RF) for each compound using Equation 1.

 
                                                                   RF=      (As)(Cis)    (Ais)(Cs)
----------------------------------------------------------------------------------------------------------------
 

                                                              Equation 1

where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Cis=Concentration of the internal standard ([mu]g/L).
Cs=Concentration of the parameter to be measured ([mu]g/L).

    If the RF value over the working range is a constant (<10% RSD), the 
RF can be assumed to be invariant and the average RF can be used for 
calculations. Alternatively, the results can be used to plot a 
calibration curve of response ratios, As/Ais, vs. 
RF.
    7.4  The working calibration curve, calibration factor, or RF must 
be verified on each working day by the measurement of one or more 
calibration standards. If the response for any parameter varies from the 
predicted response by more than 15%, a new calibration curve 
must be prepared for that compound.
    7.5  Before using any cleanup procedure, the analyst must process a 
series of calibration standards through the procedure to validate 
elution patterns and the absence of interferences from the reagents.

                           8. Quality Control

    8.1  Each laboratory that uses this method is required to operate a 
formal quality control program. The minimum requirements of this program 
consist of an initial demonstration of laboratory capability and an 
ongoing analysis of spiked samples to evaluate and document data 
quality. The laboratory must maintain records to document the quality of 
data that is generated. Ongoing data quality checks are compared with 
established performance criteria to determine if the results of analyses 
meet the performance characteristics of the method. When results of 
sample spikes indicate atypical method performance, a quality control 
check standard must be analyzed to confirm that the measurements were 
performed in an in-control mode of operation.
    8.1.1  The analyst must make an initial, one-time, demonstration of 
the ability to generate acceptable accuracy and precision with this 
method. This ability is established as described in Section 8.2.
    8.1.2  In recognition of advances that are occurring in 
chromatography, the analyst is permitted certain options (detailed in 
Sections 10.4, 11.1, and 12.1) to improve the separations or lower the 
cost of measurements. Each time such a modification is made to the 
method, the analyst is required to repeat the procedure in Section 8.2.
    8.1.3  Before processing any samples, the analyst must analyze a 
reagent water blank to demonstrate that interferences from the 
analytical system and glassware are under control. Each time a set of 
samples is extracted or reagents are changed, a reagent water blank must 
be processed as a safeguard against laboratory contamination.
    8.1.4  The laboratory must, on an ongoing basis, spike and analyze a 
minimum of 10% of all samples to monitor and evaluate laboratory data 
quality. This procedure is described in Section 8.3.
    8.1.5  The laboratory must, on an ongoing basis, demonstrate through 
the analyses of quality control check standards that the operation of 
the measurement system is in control. This procedure is described in 
Section 8.4. The frequency of the check standard analyses is equivalent 
to 10% of all samples analyzed but may be reduced if spike recoveries 
from samples (Section 8.3) meet all specified quality control criteria.
    8.1.6  The laboratory must maintain performance records to document 
the quality of data that is generated. This procedure is described in 
Section 8.5.
    8.2  To establish the ability to generate acceptable accuracy and 
precision, the analyst must perform the following operations.
    8.2.1  A quality contrml (QC) check sample concentrate is required 
containing each parameter of interest at the following concentrations in 
acetone: butyl benzyl phthalate, 10 [mu]g/mL; bis(2-ethylhexyl) 
phthalate, 50 [mu]g/mL; di-n-octyl phthalate, 50 [mu]g/mL; any other 
phthlate, 25 [mu]g/mL. The QC check sample concentrate must be obtained 
from the U.S. Environmental Protection Agancy, Environmental Monitoring 
and Support Laboratory in Cincinnati, Ohio, if available. If not 
available from that source, the QC check sample concentrate must be 
obtained from another external source. If not available from either 
source above, the QC check sample concentrate must be prepared by the 
laboratory using stock standards prepared independently from those used 
for calibration.
    8.2.2  Using a pipet, prepare QC check samples at the test 
concentrations shown in Table 2 by adding 1.00 mL of QC check sample 
concentrate to each of four 1-L aliquots of reagent water.
    8.2.3  Analyze the well-mixed QC check samples according to the 
method beginning in Section 10.
    8.2.4  Calculate the average recovery (X) in [mu]g/L, and the 
standard deviation of the recovery (s) in [mu]g/L, for each parameter 
using the four results.

[[Page 93]]

    8.2.5  For each parameter compare s and X with the corresponding 
acceptance criteria for precision and accuracy, respectively, found in 
Table 2. If s and X for all parameters of interest meet the acceptance 
criteria, the system performance is acceptable and analysis of actual 
samples can begin. If any individual s exceeds the precision limit or 
any individual X falls outside the range for accuracy, the system 
performance is unacceptable for that parameter. Locate and correct the 
source of the problem and repeat the test for all parameters of interest 
beginning with Section 8.2.2.
    8.3  The laboratory must, on an ongoing basis, spike at least 10% of 
the samples from each sample site being monitored to assess accuracy. 
For laboratories analyzing one to ten samples per month, at least one 
spiked sample per month is required.
    8.3.1  The concentration of the spike in the sample should be 
determined as follows:
    8.3.1.1  If, as in compliance monitoring, the concentration of a 
specific parameter in the sample is being checked against a regulatory 
concentration limit, the spike should be at that limit or 1 to 5 times 
higher than the background concentration determined in Section 8.3.2, 
whichever concentration would be larger.
    8.3.1.2  If the concentration of a specific parameter in the sample 
is not being checked against a limit specific to that parameter, the 
spike should be at the test concentration in Section 8.2.2 or 1 to 5 
times higher than the background concentration determined in Section 
8.3.2, whichever concentration would be larger.
    8.3.1.3  If it is impractical to determine background levels before 
spiking (e.g., maximum holding times will be exceeded), the spike 
concentration should be (1) the regulatory concentration limit, if any; 
or, if none (2) the larger of either 5 times higher than the expected 
background concentration or the test concentration in Section 8.2.2.
    8.3.2  Analyze one sample aliquot to determine the background 
concentration (B) of each parameter. If necessary, prepare a new QC 
check sample concentrate (Section 8.2.1) appropriate for the background 
concentrations in the sample. Spike a second sample aliquot with 1.0 mL 
of the QC check sample concentrate and analyze it to determine the 
concentration after spiking (A) of each parameter. Calculate each 
percent recovery (P) as 100(A-B)%/T, where T is the known true value of 
the spike.
    8.3.3  Compare the percent recovery (P) for each parameter with the 
corresponding QC acceptance criteria found in Table 2. These acceptance 
criteria were calculated to include an allowance for error in 
measurement of both the background and spike concentrations, assuming a 
spike to background ratio of 5:1. This error will be accounted for to 
the extent that the analyst's spike to background ratio approaches 
5:1.\9\ If spiking was performed at a concentration lower than the test 
concentration in Section 8.2.2, the analyst must use either the QC 
acceptance criteria in Table 2, or optional QC acceptance criteria 
calculated for the specific spike concentration. To calculate optional 
acceptance criteria for the recovery of a parameter: (1) Calculate 
accuracy (X') using the equation in Table 3, substituting the spike 
concentration (T) for C; (2) calculate overall precision (S') using the 
equation in Table 3, substituting X' for X; (3) calculate the range for 
recovery at the spike concentration as (100 X'/T)2.44(100 
S'/T)%.\9\
    8.3.4  If any individual P falls outside the designated range for 
recovery, that parameter has failed the acceptance criteria. A check 
standard containing each parameter that failed the criteria must be 
analyzed as described in Section 8.4.
    8.4  If any parameter fails the acceptance criteria for recovery in 
Section 8.3, a QC check standard containing each parameter that failed 
must be prepared and analyzed.
    Note: The frequency for the required analysis of a QC check standard 
will depend upon the number of parameters being simultaneously tested, 
the complexity of the sample matrix, and the performance of the 
laboratory.
      8.4.1  Prepare the QC check standard by adding 1.0 mL of QC check 
sample concentrate (Section 8.2.1 or 8.3.2) to 1 L of reagent water. The 
QC check standard needs only to contain the parameters that failed 
criteria in the test in Section 8.3.
      8.4.2  Analyze the QC check standard to determine the 
concentration measured (A) of each parameter. Calculate each percent 
recovery (Ps) as 100 (A/T)%, where T is the true value of the 
standard concentration.
      8.4.3  Compare the percent recovery (Ps) for each 
parameter with the corresponding QC acceptance criteria found in Table 
2. Only parameters that failed the test in Section 8.3 need to be 
compared with these criteria. If the recovery of any such parameter 
falls outside the designated range, the laboratory performance for that 
parameter is judged to be out of control, and the problem must be 
immediately identified and corrected. The analytical result for that 
parameter in the unspiked sample is suspect and may not be reported for 
regulatory compliance purposes.
      8.5  As part of the QC program for the laboratory, method accuracy 
for wastewater samples must be assessed and records must be maintained. 
After the analysis of five spiked wastewater samples as in Section 8.3, 
calculate the average percent recovery (P) and the standard deviation of 
the percent recovery (sp). Express the accuracy assessment as 
a percent recovery interval from P-2sp to P+2sp. 
If P=90% and sp=10%, for example, the accuracy interval is 
expressed as 70-110%.

[[Page 94]]

Update the accuracy assessment for each parameter on a regular basis 
(e.g. after each five to ten new accuracy measurements).
      8.6  It is recommended that the laboratory adopt additional 
quality assurance practices for use with this method. The specific 
practices that are most productive depend upon the needs of the 
laboratory and the nature of the samples. Field duplicates may be 
analyzed to assess the precision of the environmental measurements. When 
doubt exists over the identification of a peak on the chromatogram, 
confirmatory techniques such as gas chromatography with a dissimilar 
column, specific element detector, or mass spectrometer must be used. 
Whenever possible, the laboratory should analyze standard reference 
materials and participate in relevant performance evaluation studies.

            9. Sample Collection, Preservation, and Handling

    9.1  Grab samples must be collected in glass containers. 
Conventional sampling practices\10\ should be followed, except that the 
bottle must not be prerinsed with sample before collection. Composite 
samples should be collected in refrigerated glass containers in 
accordance with the requirements of the program. Automatic sampling 
equipment must be as free as possible of Tygon tubing and other 
potential sources of contamination.
    9.2  All samples must be iced or refrigerated at 4  deg.C from the 
time of collection until extraction.
    9.3  All samples must be extracted within 7 days of collection and 
completely analyzed within 40 days of extraction.\2\

                          10. Sample Extraction

    10.1  Mark the water meniscus on the side of the sample bottle for 
later determination of sample volume. Pour the entire sample into a 2-L 
separatory funnel.
    10.2  Add 60 mL of methylene chloride to the sample bottle, seal, 
and shake 30 s to rinse the inner surface. Transfer the solvent to the 
separatory funnel and extract the sample by shaking the funnel for 2 
min. with periodic venting to release excess pressure. Allow the organic 
layer to separate from the water phase for a minimum of 10 min. If the 
emulsion interface between layers is more than one-third the volume of 
the solvent layer, the analyst must employ mechanical techniques to 
complete the phrase separation. The optimum technique depends upon the 
sample, but may include stirring, filtration of the emulsion through 
glass wool, centrifugation, or other physical methods. Collect the 
methylene chloride extract in a 250-mL Erlenmeyer flask.
    10.3  Add a second 60-mL volume of methylene chloride to the sample 
bottle and repeat the extraction procedure a second time, combining the 
extracts in the Erlenmeyer flask. Perform a third extraction in the same 
manner.
    10.4  Assemble a Kuderna-Danish (K-D) concentrator by attaching a 
10-mL concentrator tube to a 500-mL evaporative flask. Other 
concentrator devices or techniques may be used in place of the K-D 
concentrator if the requirements of Section 8.2 are met.
    10.5  Pour the combined extract through a solvent-rinsed drying 
column containing about 10 cm of anhydrous sodium sulfate, and collect 
the extract in the K-D concentrator. Rinse the Erlenmeyer flask and 
column with 20 to 30 mL of methylene chloride to complete the 
quantitative transfer.
    10.6  Add one or two clean boiling chips to the evaporative flask 
and attach a three-ball Snyder column. Prewet the Snyder column by 
adding about 1 mL of methylene chloride to the top. Place the K-D 
apparatus on a hot water bath (60 to 65  deg.C) so that the concentrator 
tube is partially immersed in the hot water, and the entire lower 
rounded surface of the flask is bathed with hot vapor. Adjust the 
vertical position of the apparatus and the water temperature as required 
to complete the concentration in 15 to 20 min. At the proper rate of 
distillation the balls of the column will actively chatter but the 
chambers will not flood with condensed solvent. When the apparent volume 
of liquid reaches 1 mL, remove the K-D apparatus and allow it to drain 
and cool for at least 10 min.
    10.7  Increase the temperature of the hot water bath to about 80 
deg.C. Momentarily remove the Snyder column, add 50 mL of hexane and a 
new boiling chip, and reattach the Snyder column. Concentrate the 
extract as in Section 10.6, except use hexane to prewet the column. The 
elapsed time of concentration should be 5 to 10 min.
    10.8  Remove the Snyder column and rinse the flask and its lower 
joint into the concentrator tube with 1 to 2 mL of hexane. A 5-mL 
syringe is recommended for this operation. Adjust the extract volume to 
10 mL. Stopper the concentrator tube and store refrigerated if further 
processing will not be performed immediately. If the extract will be 
stored longer than two days, it should be transferred to a Teflon-sealed 
screw-cap vial. If the sample extract requires no further cleanup, 
proceed with gas chromatographic analysis (Section 12). If the sample 
requires further cleanup, proceed to Section 11.
    10.9  Determine the original sample volume by refilling the sample 
bottle to the mark and transferring the liquid to a 1000-mL graduated 
cylinder. Record the sample volume to the nearest 5 mL.

                       11. Cleanup and Separation

    11.  Cleanup procedures may not be necessary for a relatively clean 
sample matrix. If particular circumstances demand the use

[[Page 95]]

of a cleanup procedure, the analyst may use either procedure below or 
any other appropriate procedure. However, the analyst first must 
demonstrate that the requirements of Section 8.2 can be met using the 
method as revised to incorporate the cleanup procedure.
    11.2  If the entire extract is to be cleaned up by one of the 
following procedures, it must be concentrated to 2.0 mL. To the 
concentrator tube in Section 10.8, add a clean boiling chip and attach a 
two-ball micro-Snyder column. Prewet the column by adding about 0.5 mL 
of hexane to the top. Place the micro-K-D apparatus on a hot water bath 
(80  deg.C) so that the concentrator tube is partially immersed in the 
hot water. Adjust the vertical position of the apparatus and the water 
temperature as required to complete the concentration in 5 to 10 min. At 
the proper rate of distillation the balls of the column will actively 
chatter but the chambers will not flood. When the apparent volume of 
liquid reaches about 0.5 mL, remove the K-D apparatus and allow it to 
drain and cool for at least 10 min. Remove the micro-Snyder column and 
rinse its lower joint into the concentrator tube with 0.2 mL of hexane. 
Adjust the final volume to 2.0 mL and proceed with one of the following 
cleanup procedures.
    11.3  Florisil column cleanup for phthalate esters:
    11.3.1  Place 10 g of Florisil into a chromatographic column. Tap 
the column to settle the Florisil and add 1 cm of anhydrous sodium 
sulfate to the top.
    11.3.2  Preelute the column with 40 mL of hexane. The rate for all 
elutions should be about 2 mL/min. Discard the eluate and just prior to 
exposure of the sodium sulfate layer to the air, quantitatively transfer 
the 2-mL sample extract onto the column using an additional 2 mL of 
hexane to complete the transfer. Just prior to exposure of the sodium 
sulfate layer to the air, add 40 mL of hexane and continue the elution 
of the column. Discard this hexane eluate.
    11.3.3  Next, elute the column with 100 mL of 20% ethyl ether in 
hexane (V/V) into a 500-mL K-D flask equipped with a 10-mL concentrator 
tube. Concentrate the collected fraction as in Section 10.6. No solvent 
exchange is necessary. Adjust the volume of the cleaned up extract to 10 
mL in the concentrator tube and analyze by gas chromatography (Section 
12).
    11.4  Alumina column cleanup for phthalate esters:
    11.4.1  Place 10 g of alumina into a chromatographic column. Tap the 
column to settle the alumina and add 1 cm of anhydrous sodium sulfate to 
the top.
    11.4.2  Preelute the column with 40 mL of hexane. The rate for all 
elutions should be about 2 mL/min. Discard the eluate and just prior to 
exposure of the sodium sulfate layer to the air, quantitatively transfer 
the 2-mL sample extract onto the column using an additional 2 mL of 
hexane to complete the transfer. Just prior to exposure of the sodium 
sulfate layer to the air, add 35 mL of hexane and continue the elution 
of the column. Discard this hexane eluate.
    11.4.3  Next, elute the column with 140 mL of 20% ethyl ether in 
hexane (V/V) into a 500-mL K-D flask equipped with a 10-mL concentrator 
type. Concentrate the collected fraction as in Section 10.6. No solvent 
exchange is necessary. Adjust the volume of the cleaned up extract to 10 
mL in the concentrator tube and analyze by gas chromatography (Section 
12).

                         12. Gas Chromatography

    12.1  Table 1 summarizes the recommended operating conditions for 
the gas chromatograph. Included in this table are retention times and 
MDL that can be achieved under these conditions. Examples of the 
separations achieved by Column 1 are shown in Figures 1 and 2. Other 
packed or capillary (open-tubular) columns, chromatographic conditions, 
or detectors may be used if the requirements of Section 8.2 are met.
    12.2  Calibrate the system daily as described in Section 7.
    12.3  If the internal standard calibration procedure is being used, 
the internal staldard must be added to the sample extract and mixed 
thoroughly immediately before injection into the gas chromatograph.
    12.4  Inject 2 to 5 [mu]L of the sample extract or standard into the 
gas-chromatograph using the solvent-flush technique.\11\ Smaller (1.0 
[mu]L) volumes may be injected if automatic devices are employed. Record 
the volume injected to the nearest 0.05 [mu]L, and the resulting peak 
size in area or peak height units.
    12.5  Identify the parameters in the sample by comparing the 
retention times of the peaks in the sample chromatogram with those of 
the peaks in standard chromatograms. The width of the retention time 
window used to make identifications should be based upon measurements of 
actual retention time variations of standards over the course of a day. 
Three times the standard deviation of a retention time for a compound 
can be used to calculate a suggested window size; however, the 
experience of the analyst should weigh heavily in the interpretation of 
chromatograms.
    12.6  If the response for a peak exceeds the working range of the 
system, dilute the extract and reanalyze.
    12.7  If the measurement of the peak response is prevented by the 
presence of interferences, further cleanup is required.

                            13. Calculations

    13.1  Determine the concentration of individual compounds in the 
sample.

[[Page 96]]

    13.1.1  If the external standard calibration procedure is used, 
calculate the amount of material injected from the peak response using 
the calibration curve or calibration factor determined in Section 7.2.2. 
The concentration in the sample can be calculated from Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.103

                                                              Equation 2

where:
A=Amount of material injected (ng).
Vi=Volume of extract injected ([mu]L).
Vt=Volume of total extract ([mu]L).
Vs=Volume of water extracted (mL).

    13.1.2  If the internal standard calibration procedure is used, 
calculate the concentration in the sample using the response factor (RF) 
determined in Section 7.3.2 and Equation 3.
[GRAPHIC] [TIFF OMITTED] TC15NO91.104

                                                              Equation 3

where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Is=Amount of internal standard added to each extract ([mu]g).
Vo=Volume of water extracted (L).

    13.2  Report results in [mu]g/L without correction for recovery 
data. All QC data obtained should be reported with the sample results.

                         14. Method Performance

    14.1  The method detection limit (MDL) is defined as the minimum 
concentration of a substance that can be measured and reported with 99% 
confidence that the value is above zero.\1\ The MDL concentrations 
listed in Table 1 were obtained using reagent water.\12\ Similar results 
were achieved using representative wastewaters. The MDL actually 
achieved in a given analysis will vary depending on instrument 
sensitivity and matrix effects.
    14.2  This method has been tested for linearity of spike recovery 
from reagent water and has been demonstrated to be applicable over the 
concentration range from 5 x MDL to 1000 x MDL with the following 
exceptions: dimethyl and diethyl phthalate recoveries at 1000 x MDL were 
low (70%); bis-2-ethylhexyl and di-n-octyl phthalate recoveries at 5 x 
MDL were low (60%).\12\
    14.3  This method was tested by 16 laboratories using reagent water, 
drinking water, surface water, and three industrial wastewaters spiked 
at six concentrations over the range 0.7 to 106 [mu]g/L.\13\ Single 
operator precision, overall precision, and method accuracy were found to 
be directly related to the concentration of the parameter and 
essentially independent of the sample matrix. Linear equations to 
describe these relationships are presented in Table 3.

                               References

    1. 40 CFR part 136, appendix B.
    2. ``Determination of Phthalates in Industrial and Muncipal 
Wastewaters,'' EPA 600/4-81-063, National Technical Information Service, 
PB81-232167, Springfield, Virginia 22161, July 1981.
    3. ASTM Annual Book of Standards, Part 31, D3694-78. ``Standard 
Practices for Preparation of Sample Containers and for Preservation of 
Organic Constituents,'' American Society for Testing and Materials, 
Philadelphia.
    4. Giam, C.S., Chan, H.S., and Nef, G.S. ``Sensitive Method for 
Determination of Phthalate Ester Plasticizers in Open-Ocean Biota 
Samples,'' Analytical Chemistry, 47, 2225 (1975).
    5. Giam, C.S., and Chan, H.S. ``Control of Blanks in the Analysis of 
Phthalates in Air and Ocean Biota Samples,'' U.S. National Bureau of 
Standards, Special Publication 442, pp. 701-708, 1976.
    6. ``Carcinogens--Working with Carcinogens,'' Department of Health, 
Education, and Welfare, Public Health Service, Center for Disease 
Control, National Institute for Occupational Safety and Health, 
Publication No. 77-206, August 1977.
    7. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR 
part 1910), Occupational Safety and Health Administration, OSHA 2206 
(Revised, January 1976).
    8. ``Safety in Academic Chemistry Laboratories,'' American Chemical 
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
    9. Provost L.P., and Elder, R.S. ``Interpretation of Percent 
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44 
used in the equation in Section 8.3.3 is two times the value 1.22 
derived in this report.)
    10. ASTM Annual Book of Standards, Part 31, D3370-76. ``Standard 
Practices for Sampling Water,'' American Society for Testing and 
Materials, Philadelphia.
    11. Burke, J.A. ``Gas Chromatography for Pesticide Residue Analysis; 
Some Practical Aspects,'' Journal of the Association of Official 
Analytical Chemists, 48, 1037 (1965).
    12. ``Method Detection Limit and Analytical Curve Studies, EPA 
Methods 606, 607, and 608,'' Special letter report for EPA Contract 68-
03-2606, U.S. Environmental Protection Agency, Environmental Monitoring 
and Support Laboratory, Cincinnati, Ohio 45268, June 1980.

[[Page 97]]

    13. ``EPA Method Study 16 Method 606 (Phthalate Esters),'' EPA 600/
4-84-056, National Technical Information Service, PB84-211275, 
Springfield, Virginia 22161, June 1984.

     Table 1--Chromatographic Conditions and Method Detection Limits
------------------------------------------------------------------------
                                   Retention time (min)        Method
                               ----------------------------   detection
           Parameter                                        limit ([mu]g/
                                  Column 1      Column 2         L)
------------------------------------------------------------------------
Dimethyl phthalate............          2.03          0.95          0.29
Diethyl phthalate.............          2.82          1.27          0.49
Di-n-butyl phthalate..........          8.65          3.50          0.36
Butyl benzyl phthalate........        a 6.94        a 5.11          0.34
Bis(2-ethylhexyl) phthalate...        a 8.92       a 10.5           2.0
Di-n-octyl phthalate..........       a 16.2        a 18.0           3.0
------------------------------------------------------------------------
Column 1 conditions: Supelcoport (100/120 mesh) coated with 1.5% SP-2250/
  1.95% SP-2401 packed in a 1.8 m long x 4 mm ID glass column with 5%
  methane/95% argon carrier gas at 60 mL/min flow rate. Column
  temperature held isothermal at 180 deg.C, except where otherwise
  indicated.
Column 2 conditions: Supelcoport (100/120 mesh) coated with 3% OV-1
  packed in a 1.8 m long x 4 mm ID glass column with 5% methane/95%
  argon carrier gas at 60 mL/min flow rate. Column temperature held
  isothermal at 200  deg.C, except where otherwise indicated.
a 220  deg.C column temperature.


                                   Table 2--QC Acceptance Criteria--Method 606
----------------------------------------------------------------------------------------------------------------
                                                                        Test    Limit for   Range for  Range for
                             Parameter                                 conc.    s ([mu]g/   X ([mu]g/    P, Ps
                                                                     ([mu]g/L)      L)         L)      (percent)
----------------------------------------------------------------------------------------------------------------
Bis(2-ethylhexyl) phthalate........................................         50       38.4    1.2-55.9      D-158
Butyl benzyl phthalate.............................................         10        4.2    5.7-11.0     30-136
Di-n-butyl phthalate...............................................         25        8.9   10.3-29.6     23-136
Diethyl phthalate..................................................         25        9.0    1.9-33.4      D-149
Dimethyl phathalate................................................         25        9.5    1.3-35.5      D-156
Di-n-octyl phthalate...............................................         50       13.4      D-50.0      D-114
----------------------------------------------------------------------------------------------------------------
s=Standard deviation of four recovery measurements, in [mu]g/L (Section 8.2.4).
X=Average recovery for four recovery measurements, in [mu]g/L (Section 8.2.4).
P, Ps=Percent recovery measured (Section 8.3.2, Section 8.4.2).
D=Detected; result must be greater than zero.
 
Note: These criteria are based directly upon the method performance data in Table 3. Where necessary, the limits
  for recovery have been broadened to assure applicability of the limits to concentrations below those used to
  develop Table 3.


                Table 3--Method Accuracy and Precision as Functions of Concentration--Method 606
----------------------------------------------------------------------------------------------------------------
                                                                   Accuracy, as   Single analyst      Overall
                            Parameter                              recovery, X'   precision, sr'   precision, S'
                                                                     ([mu]g/L)       ([mu]g/L)       ([mu]g/L)
----------------------------------------------------------------------------------------------------------------
Bis(2-ethylhexyl) phthalate.....................................      0.53C+2.02      0.80X-2.54      0.73X-0.17
Butyl benzyl phthalate..........................................      0.82C+0.13      0.26X+0.04      0.25X+0.07
Di-n-butyl phthalate............................................      0.79C+0.17      0.23X+0.20      0.29X+0.06
Diethyl phthalate...............................................      0.70C+0.13      0.27X+0.05      0.45X+0.11
Dimethyl phthalate..............................................      0.73C+0.17      0.26X+0.14      0.44X+0.31
Di-n-octyl phthalate............................................      0.35C-0.71      0.38X+0.71      0.62X+0.34
----------------------------------------------------------------------------------------------------------------
X'=Expected recovery for one or more measurements of a sample containing a concentration of C, in [mu]g/L.
sr'=Expected single analyst standard deviation of measurements at an average concentration found of X, in [mu]g/
  L.
S'=Expected interlaboratory standard deviation of measurements at an average concentration found of X, in [mu]g/
  L.
C=True value for the concentration, in [mu]g/L.
X=Average recovery found for measurements of samples containing a concentration of C, in [mu]g/L.


[[Page 98]]

[GRAPHIC] [TIFF OMITTED] TC02JY92.015


[[Page 99]]

[GRAPHIC] [TIFF OMITTED] TC02JY92.016


[[Page 100]]

                        Method 607--Nitrosamines

                        1. Scope and Application

    1.1  This method covers the determination of certain nitrosamines. 
The following parameters can be determined by this method:

------------------------------------------------------------------------
                   Parameter                     Storet No.    CAS No.
------------------------------------------------------------------------
N-Nitrosodimethylamine........................        34438      62-75-9
N-Nitrosodiphenylamine........................        34433      86-30-6
N-Nitrosodi-n-propylamine.....................        34428     621-64-7
------------------------------------------------------------------------

    1.2  This is a gas chromatographic (GC) method applicable to the 
determination of the parameters listed above in municipal and industrial 
discharges as provided under 40 CFR 136.1. When this method is used to 
analyze unfamiliar samples for any or all of the compmunds above, 
compound identifications should be supported by at least one additional 
qualitative technique. This method describes analytical conditimns for a 
second gas chromatographic column that can be used to confirm 
measurements made with the primary column. Method 625 provides gas 
chromatograph/mass spectrometer (GC/MS) conditions appropriate for the 
qualitative and quantitative confirmation of results for N-nitrosodi-n-
propylamine. In order to confirm the presence of N-nitrosodiphenylamine, 
the cleanup procedure specified in Section 11.3 or 11.4 must be used. In 
order to confirm the presence of N-nitrosodimethylamine by GC/MS, Column 
1 of this method must be substituted for the column recommended in 
Method 625. Confirmation of these parameters using GC-high resolution 
mass spectrometry or a Thermal Energy Analyzer is also recommended. 
1,2
    1.3  The method detection limit (MDL, defined in Section 
14.1)3 for each parameter is listed in Table 1. The MDL for a 
specific wastewater may differ from those listed, depending upon the 
nature of interferences in the sample matrix.
    1.4  Any modification of this method, beyond those expressly 
permitted, shall be considered as a major modification subject to 
application and approval of alternate test procedures under 40 CFR 136.4 
and 136.5.
    1.5  This method is restricted to use by or under the supervision of 
analysts experienced in the use of a gas chromatograph and in the 
interpretation of gas chromatograms. Each analyst must demonstrate the 
ability to generate acceptable results with this method using the 
procedure described in Section 8.2.

                          2. Summary of Method

    2.1  A measured volume of sample, approximately 1-L, is extracted 
with methylene chloride using a separatory funnel. The methylene 
chloride extract is washed with dilute hydrochloric acid to remove free 
amines, dried, and concentrated to a volume of 10 mL or less. After the 
extract has been exchanged to methanol, it is separated by gas 
chromatography and the parameters are then measured with a nitrogen-
phosphorus detector.4
    2.2  The method provides Florisil and alumina column cleanup 
procedures to separate diphenylamine from the nitrosamines and to aid in 
the elimination of interferences that may be encountered.

                            3. Interferences

    3.1  Method interferences may be caused by contaminants in solvents, 
reagents, glassware, and other sample processing hardware that lead to 
discrete artifacts and/or elevated baselines in gas chromatograms. All 
of these materials must be routinely demonstrated to be free from 
interferences under the conditions of the analysis by running laboratory 
reagent blanks as described in Section 8.1.3.
    3.1.1  Glassware must be scrupulously cleaned.5 Clean all 
glassware as soon as possible after use by rinsing with the last solvent 
used in it. Solvent rinsing should be followed by detergent washing with 
hot water, and rinses with tap water and distilled water. The glassware 
should then be drained dry, and heated in a muffle furnace at 400  deg.C 
for 15 to 30 min. Solvent rinses with acetone and pesticide quality 
hexane may be substituted for the muffle furnace heating. Volumetric 
ware should not be heated in a muffle furnace. After drying and cooling, 
glassware should be sealed and stored in a clean environment to prevent 
any accumulation of dust or other contaminants. Store inverted or capped 
with aluminum foil.
    3.1.2  The use of high purity reagents and solvents helps to 
minimize interference problems. Purification of solvents by distillation 
in all-glass systems may be required.
    3.2  Matrix interferences may be caused by contaminants that are co-
extracted from the sample. The extent of matrix interferences will vary 
considerably from source to source, depending upon the nature and 
diversity of the industrial complex or municipality being sampled. The 
cleanup procedures in Section 11 can be used to overcome many of these 
interferences, but unique samples may require additional cleanup 
approaches to achieve the MDL listed in Table 1.
    3.3  N-Nitrosodiphenylamine is reported6-9 to undergo 
transnitrosation reactions. Care must be exercised in the heating or 
concentrating of solutions containing this compound in the presence of 
reactive amines.
    3.4  The sensitive and selective Thermal Energy Analyzer and the 
reductive Hall detector may be used in place of the nitrogen-phosphorus 
detector when interferences are encountered. The Thermal Energy Analyzer 
offers the highest selectivity of the non-MS detectors.

[[Page 101]]

                                4. Safety

    4.1  The toxicity or carcinogenicity of each reagent used in this 
method has not been precisely defined; however, each chemical compound 
should be treated as a potential health hazard. From this viewpoint, 
exposure to these chemicals must be reduced to the lowest possible level 
by whatever means available. The laboratory is responsible for 
maintaining a current awareness file of OSHA regulations regarding the 
safe handling of the chemicals specified in this method. A reference 
file of material data handling sheets should also be made available to 
all personnel involved in the chemical analysis. Additional references 
to laboratory safety are available and have been identified 
10-12 for the information of the analyst.
    4.2  These nitrosamines are known carcinogens 13-17, 
therefore, utmost care must be exercised in the handling of these 
materials. Nitrosamine reference standards and standard solutions should 
be handled and prepared in a ventilated glove box within a properly 
ventilated room.

                       5. Apparatus and Materials

    5.1  Sampling equipment, for discrete or composite sampling.
    5.1.1  Grab sample bottle--1-L or 1-qt, amber glass, fitted with a 
screw cap lined with Teflon. Foil may be substituted for Teflon if the 
sample is not corrosive. If amber bottles are not available, protect 
samples from light. The bottle and cap liner must be washed, rinsed with 
acetone or methylene chloride, and dried before use to minimize 
contamination.
    5.1.2  Automatic sampler (optional)--The sampler must incorporate 
glass sample containers for the collection of a minimum of 250 mL of 
sample. Sample containers must be kept refrigerated at 4  deg.C and 
protected from light during compositing. If the sampler uses a 
peristaltic pump, a minimum length of compressible silicone rubber 
tubing may be used. Before use, however, the compressible tubing should 
be thoroughly rinsed with methanol, followed by repeated rinsings with 
distilled water to minimize the potential for contamination of the 
sample. An integrating flowmeter is required to collect flow 
proportional composites.
    5.2  Glassware (All specifications are suggested. Catalog numbers 
are included for illustration only.):
    5.2.1  Separatory funnels--2-L and 250-mL, with Teflon stopcock.
    5.2.2  Drying column--Chromatographic column, approximately 400 mm 
long x 19 mm ID, with coarse frit filter disc.
    5.2.3  Concentrator tube, Kuderna-Danish--10-mL, graduated (Kontes 
K-570050-1025 or equivalent). Calibration must be checked at the volumes 
employed in the test. Ground glass stopper is used to prevent 
evaporation of extracts.
    5.2.4  Evaporative flask, Kuderna-Danish--500-mL (Kontes K-570001-
0500 or equivalent). Attach to concentrator tube with springs.
    5.2.5  Snyder column, Kuderna-Danish--Three-ball macro (Kontes K-
503000-0121 or equivalent).
    5.2.6  Snyder column, Kuderna-Danish--Two-ball micro (Kontes K-
569001-0219 or equivalent).
    5.2.7  Vials--10 to 15-mL, amber glass, with Teflon-lined screw cap.
    5.2.8  Chromatographic column--Approximately 400 mm long x 22 mm ID, 
with Teflon stopcock and coarse frit filter disc at bottom (Kontes K-
420540-0234 or equivalent), for use in Florisil column cleanup 
procedure.
    5.2.9  Chromatographic column--Approximately 300 mm long x 10 mm ID, 
with Teflon stopcock and coarse frit filter disc at bottom (Kontes K-
420540-0213 or equivalent), for use in alumina column cleanup procedure.
    5.3  Boiling chips--Approximately 10/40 mesh. Heat to 400  deg.C for 
30 min or Soxhlet extract with methylene chloride.
    5.4  Water bath--Heated, with concentric ring cover, capable of 
temperature control (2  deg.C). The bath should be used in a 
hood.
    5.5  Balance--Analytical, capable of accurately weighing 0.0001 g.
    5.6  Gas chromatograph--An analytical system complete with gas 
chromatograph suitable for on-column injection and all required 
accessories including syringes, analytical columns, gases, detector, and 
strip-chart recorder. A data system is recommended for measuring peak 
areas.
    5.6.1  Column 1--1.8 m long x 4 mm ID glass, packed with 10% 
Carbowax 20 M/2% KOH on Chromosorb W-AW (80/100 mesh) or equivalent. 
This column was used to develop the method performance statements in 
Section 14. Guidelines for the use of alternate column packings are 
provided in Section 12.2.
    5.6.2  Column 2--1.8 m long x 4 mm ID glass, packed with 10% SP-2250 
on Supel- coport (100/120 mesh) or equivalent.
    5.6.3  Detector--Nitrogen-phosphorus, reductive Hall, or Thermal 
Energy Analyzer detector.\1,\ \2\ These detectors have proven effective 
in the analysis of wastewaters for the parameters listed in the scope 
(Section 1.1). A nitrogen-phosphorus detector was used to develop the 
method performance statements in Section 14. Guidelines for the use of 
alternate detectors are provided in Section 12.2.

                               6. Reagents

    6.1  Reagent water--Reagent water is defined as a water in which an 
interferent is not observed at the MDL of the parameters of interest.
    6.2  Sodium hydroxide solution (10 N)--Dissolve 40 g of NaOH (ACS) 
in reagent water and dilute to 100 ml.

[[Page 102]]

    6.3  Sodium thiosulfate--(ACS) Granular.
    6.4  Sulfuric acid (1+1)--Slowly, add 50 mL of H2SO4 
(ACS, sp. gr. 1.84) to 50 mL of reagent water.
    6.5  Sodium sulfate--(ACS) Granular, anhydrous. Purify by heating at 
400  deg.C for 4 h in a shallow tray.
    6.6  Hydrochloric acid (1+9)--Add one volume of concentrated HCl 
(ACS) to nine volumes of reagent water.
    6.7  Acetone, methanol, methylene chloride, pentane--Pesticide 
quality or equivalent.
    6.8  Ethyl ether--Nanograde, redistilled in glass if necessary.
    6.8.1  Ethyl ether must be shown to be free of peroxides before it 
is used as indicated by EM Laboratories Quant test strips. (Available 
from Scientific Products Co., Cat No. P1126-8, and other suppliers.)
    6.8.2  Procedures recommended for removal of peroxides are provided 
with the test strips. After cleanup, 20 mL of ethyl alcohol preservative 
must be added to each liter of ether.
    6.9  Florisil--PR grade (60/100 mesh). Purchase activated at 1250 
deg.F and store in the dark in glass containers with ground glass 
stoppers or foil-lined screw caps. Before use, activate each batch at 
least 16 h at 130  deg.C in a foil-covered glass container and allow to 
cool.
    6.10  Alumina--Basic activity Super I, W200 series (ICN Life 
Sciences Group, No. 404571, or equivalent). To prepare for use, place 
100 g of alumina into a 500-mL reagent bottle and add 2 mL of reagent 
water. Mix the alumina preparation thoroughly by shaking or rolling for 
10 min and let it stand for at least 2 h. The preparation should be 
homogeneous before use. Keep the bottle sealed tightly to ensure proper 
activity.
    6.11  Stock standard solutions (1.00 [mu]g/[mu]L)--Stock standard 
solutions can be prepared from pure standard materials or purchased as 
certified solutions.
    6.11.1  Prepare stock standard solutions by accurately weighing 
about 0.0100 g of pure material. Dissolve the material in methanol and 
dilute to volume in a 10-mL volumetric flask. Larger volumes can be used 
at the convenience of the analyst. When compound purity is assayed to be 
96% or greater, the weight can be used without correction to calculate 
the concentration of the stock standard. Commercially prepared stock 
standards can be used at any concentration if they are certified by the 
manufacturer or by an independent source.
    6.11.2  Transfer the stock standard solutions into Teflon-sealed 
screw-cap bottles. Store at 4  deg.C and protect from light. Stock 
standard solutions should be checked frequently for signs of degradation 
or evaporation, especially just prior to preparing calibration standards 
from them.
    6.11.3  Stock standard solutions must be replaced after six months, 
or sooner if comparison with check standards indicates a problem.
    6.12  Quality control check sample concentrate--See Section 8.2.1.

                             7. Calibration

    7.1  Establish gas chromatographic operating conditions equivalent 
to those given in Table 1. The gas chromatographic system can be 
calibrated using the external standard technique (Section 7.2) or the 
internal standard technique (Section 7.3).
    7.2  External standard calibration procedure:
    7.2.1  Prepare calibration standards at a minimum of three 
concentration levels for each parameter of interest by adding volumes of 
one or more stock standards to a volumetric flask and diluting to volume 
with methanol. One of the external standards should be at a concentraton 
near, but above, the MDL (Table 1) and the other concentrations should 
correspond to the expected range of concentrations found in real samples 
or should define the working range of the detector.
    7.2.2  Using injections of 2 to 5 [mu]L, analyze each calibration 
standard according to Section 12 and tabulate peak height or area 
responses against the mass injected. The results can be used to prepare 
a calibration curve for each compound. Alternatively, if the ratio of 
response to amount injected (calibration factor) is a constant over the 
working range (<10% relative standard deviation, RSD), linearity through 
the origin can be assumed and the average ratio or calibration factor 
can be used in place of a calibration curve.
    7.3  Internal standard calibration procedure--To use this approach, 
the analyst must select one or more internal standards that are similar 
in analytical behavior to the compounds of interest. The analyst must 
further demonstrate that the measurement of the internal standard is not 
affected by method or matrix interferences. Because of these 
limitations, no internal standard can be suggested that is applicable to 
all samples.
    7.3.1  Prepare calibration standards at a minimum of three 
concentration levels for each parameter of interest by adding volumes of 
one or more stock standards to a volumetric flask. To each calibration 
standard, add a known constant amount of one or more internal standards, 
and dilute to volume with methanol. One of the standards should be at a 
concentration near, but above, the MDL and the other concentrations 
should correspond to the expected range of concentrations found in real 
samples or should define the working range of the detector.

[[Page 103]]

    7.3.2  Using injections of 2 to 5 [mu]L, analyze each calibration 
standard according to Section 12 and tabulate peak height or area 
responses against concentration for each compound and internal standard. 
Calculate response factors (RF) for each compound using Equation 1.

 
                                                                   RF=      (As)(Cis)    (Ais)(Cs)
----------------------------------------------------------------------------------------------------------------
 

                                                              Equation 1

where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Cis=Concentration of the internal standard ([mu]g/L).
Cs=Concentration of the parameter to be measured ([mu]g/L).

    If the RF value over the working range is a constant (<10% RSD), the 
RF can be assumed to be invariant and the average RF can be used for 
calculations. Alternatively, the results can be used to plot a 
calibration curve of response ratios, As/Ais, vs. 
RF.
    7.4  The working calibration curve, calibration factor, or RF must 
be verified on each working day by the measurement of one or more 
calibration standards. If the response for any parameter varies from the 
predicted response by more than 15%, a new calibration curve 
must be prepared for that compound.
    7.5  Before using any cleanup procedure, the analyst must process a 
series of calibration standards through the procedure to validate 
elution patterns and the absence of interferences from the reagents.

                           8. Quality Control

    8.1  Each laboratory that uses this method is required to operate a 
formal quality control program. The minimum requirements of this program 
consist of an initial demonstration of laboratory capability and an 
ongoing analysis of spiked samples to evaluate and document data 
quality. The laboratory must maintain records to document the quality of 
data that is generated. Ongoing data quality checks are compared with 
established performance criteria to determine if the results of analyses 
meet the performance characteristics of the method. When results of 
sample spikes indicate atypical method performance, a quality control 
check standard must be analyzed to confirm that the measurements were 
performed in an in-control mode of operation.
    8.1.1  The analyst must make an initial, one-time, demonstration of 
the ability to generate acceptable accuracy and precision with this 
method. This ability is established as described in Section 8.2.
    8.1.2  In recognition of advances that are occurring in 
chromatography, the analyst is permitted certain options (detailed in 
Sections 10.4, 11.1, and 12.2) to improve the separations or lower the 
cost of measurements. Each time such a modification is made to the 
method, the analyst is required to repeat the procedure in Section 8.2.
    8.1.3  Before processing any samples, the analyst must analyze a 
reagent water blank to demonstrate that interferences from the 
analytical system and glassware are under control. Each time a set of 
samples is extracted or reagents are changed, a reagent water blank must 
be processed as a safeguard against laboratory contamination.
    8.1.4  The laboratory must, on an ongoing basis, spike and analyze a 
minimum of 10% of all samples to monitor and evaluate laboratory data 
quality. This procedure is described in Section 8.3.
    8.1.5  The laboratory must, on an ongoing basis, demonstrate through 
the analyses of quality control check standards that the operation of 
the measurement system is in control. This procedure is described in 
Section 8.4. The frequency of the check standard analyses is equivalent 
to 10% of all samples analyzed but may be reduced if spike recoveries 
from samples (Section 8.3) meet all specified quality control criteria.
    8.1.6  The laboratory must maintain performance records to document 
the quality of data that is generated. This procedure is described in 
Section 8.5.
    8.2  To establish the ability to generate acceptable accuracy and 
precision, the analyst must perform the following operations.
    8.2.1  A quality control (QC) check sample concentrate is required 
containing each parameter of interest at a concentration of 20 [mu]g/mL 
in methanol. The QC check sample concentrate must be obtained from the 
U.S. Environmental Protection Agency, Environmental Monitoring and 
Support Laboratory in Cincinnati, Ohio, if available. If not available 
from that source, the QC check sample concentrate must be obtained from 
another external source. If not available from either source above, the 
QC check sample concentrate must be prepared by the laboratory using 
stock standards prepared independently from those used for calibration.
    8.2.2  Using a pipet, prepare QC check samples at a concentration of 
20 [mu]g/L by adding 1.00 mL of QC check sample concentrate to each of 
four 1-L aliquots of reagent water.
    8.2.3  Analyze the well-mixed QC check samples according to the 
method beginning in Section 10.
    8.2.4  Calculate the average recovery (X) in [mu]g/L, and the 
standard deviation of the recovery (s) in [mu]g/L, for each parameter 
using the four results.
    8.2.5  For each parameter compare s and X with the corresponding 
acceptance criteria for precision and accuracy, respectively,

[[Page 104]]

found in Table 2. If s and X for all parameters of interest meet the 
acceptance criteria, the system performance is acceptable and analysis 
of actual samples can begin. If any individual s exceeds the precision 
limit or any individual X falls outside the range for accuracy, the 
system performance is unacceptable for that parameter. Locate and 
correct the source of the problem and repeat the test for all parameters 
of interest beginning with Section 8.2.2.
    8.3  The laboratory must, on an ongoing basis, spike at least 10% of 
the samples from each sample site being monitored to assess accuracy. 
For laboratories analyzing one to ten samples per month, at least one 
spiked sample per month is required.
    8.3.1  The concentration of the spike in the sample should be 
determined as follows:
    8.3.1.1  If, as in compliance monitoring, the concentration of a 
specific parameter in the sample is being checked against a regulatory 
concentration limit, the spike should be at that limit or 1 to 5 times 
higher than the background concentration determined in Section 8.3.2, 
whichever concentration would be larger.
    8.3.1.2  If the concentration of a specific parameter in the sample 
is not being checked against a limit specific to that parameter, the 
spike should be at 20 [mu]g/L or 1 to 5 times higher than the background 
concentration determined in Section 8.3.2, whichever concentration would 
be larger.
    8.3.1.3  If it is impractical to determine background levels before 
spiking (e.g., maximum holding times will be exceeded), the spike 
concentration should be (1) the regulatory concentration limit, if any; 
or, if none (2) the larger of either 5 times higher than the expected 
background concentration or 20 [mu]g/L.
    8.3.2  Analyze one sample aliquot to determine the background 
concentration (B) of each parameter. If necessary, prepare a new QC 
check sample concentrate (Section 8.2.1) appropriate for the background 
concentrations in the sample. Spike a second sample aliquot with 1.0 mL 
of the QC check sample concentrate and analyze it to determine the 
concentration after spiking (A) of each parameter. Calculate each 
percent recovery (P) as 100(A-B)%/T, where T is the known true value of 
the spike.
    8.3.3  Compare the percent recovery (P) for each parameter with the 
corresponding QC acceptance criteria found in Table 2. These acceptance 
criteria were caluclated to include an allowance for error in 
measurement of both the background and spike concentrations, assuming a 
spike to background ratio of 5:1. This error will be accounted for to 
the extent that the analyst's spike to background ratio approaches 
5:1.\18\ If spiking was performed at a concentration lower than 20 
[mu]g/L, the analyst must use either the QC acceptance criteria in Table 
2, or optional QC acceptance criteria caluclated for the specific spike 
concentration. To calculate optional acceptance crtieria for the 
recovery of a parameter: (1) Calculate accuracy (X') using the equation 
in Table 3, substituting the spike concentration (T) for C; (2) 
calculate overall precision (S') using the equation in Table 3, 
substituting X' for X; (3) calculate the range for recovery at the spike 
concentration as (100 X'/T)  2.44(100 S'/T)%.\18\
    8.3.4  If any individual P falls outside the designated range for 
recovery, that parameter has failed the acceptance criteria. A check 
standard containing each parameter that failed the criteria must be 
analyzed as described in Section 8.4.
    8.4  If any parameter fails the acceptance criteria for recovery in 
Section 8.3, a QC check standard containing each parameter that failed 
must be prepared and analyzed.
    Note: The frequency for the required analysis of a QC check standard 
will depend upon the number of parameters being simultaneously tested, 
the complexity of the sample matrix, and the performance of the 
laboratory.
    8.4.1  Prepare the QC check standard by adding 1.0 mL of QC check 
sample concentrate (Section 8.2.1 or 8.3.2) to 1 L of reagent water. The 
QC check standard needs only to contain the parameters that failed 
criteria in the test in Section 8.3.
    8.4.2  Analyze the QC check standard to determine the concentration 
measured (A) of each parameter. Calculate each percent recovery 
(Ps) as 100 (A/T)%, where T is the true value of the standard 
concentration.
    8.4.3  Compare the percent recovery (Ps) for each 
parameter with the corresponding QC acceptance criteria found in Table 
2. Only parameters that failed the test in Section 8.3 need to be 
compared with these criteria. If the recovery of any such parameter 
falls outside the designated range, the laboratory performance for that 
parameter is judged to be out of control, and the problem must be 
immediately identified and corrected. The analytical result for that 
parameter in the unspiked sample is suspect and may not be reported for 
regulatory compliance purposes.
    8.5  As part of the QC program for the laboratory, method accuracy 
for wastewater samples must be assessed and records must be maintained. 
After the analysis of five spiked wastewater samples as in Section 8.3, 
calculate the average percent recovery (P) and the standard deviation of 
the percent recovery (sp). Express the accuracy assessment as 
a percent recovery interval from P-2sp to P+2sp. 
If P=90% and sp=10%, for example, the accuracy interval is 
expressed as 70-110%. Update the accuracy assessment for each parameter 
on a regular basis (e.g. after each five to ten new accuracy 
measurements).
    8.6  It is recommended that the laboratory adopt additional quality 
assurance practices

[[Page 105]]

for use with this method. The specific practices that are most 
productive depend upon the needs of the laboratory and the nature of the 
samples. Field duplicates may be analyzed to assess the precision of the 
environmental measurements. When doubt exists over the identification of 
a peak on the chromatogram, confirmatory techniques such as gas 
chromatography with a dissimilar column, specific element detector, or 
mass spectrometer must be used. Whenever possible, the laboratory should 
analyze standard reference materials and participate in relevant 
performance evaluation studies.

            9. Sample Collection, Preservation, and Handling

    9.1  Grab samples must be collected in glass containers. 
Conventional sampling practices \19\ should be followed, except that the 
bottle must not be prerinsed with sample before collection. Composite 
samples should be collected in refrigerated glass containers in 
accordance with the requirements of the program. Automatic sampling 
equipment must be as free as possible of Tygon tubing and other 
potential sources of contamination.
    9.2  All samples must be iced or refrigerated at 4  deg.C from the 
time of collection until extraction. Fill the sample bottles and, if 
residual chlorine is present, add 80 mg of sodium thiosulfate per liter 
of sample and mix well. EPA Methods 330.4 and 330.5 may be used for 
measurement of residual chlorine.\20\ Field test kits are available for 
this purpose. If N-nitrosodiphenylamine is to be determined, adjust the 
sample pH to 7 to 10 with sodium hydroxide solution or sulfuric acid.
    9.3  All samples must be extracted within 7 days of collection and 
completely analyzed within 40 days of extraction.\4\
    9.4  Nitrosamines are known to be light sensitive.\7\ Samples should 
be stored in amber or foil-wrapped bottles in order to minimize 
photolytic decomposition.

                          10. Sample Extraction

    10.1  Mark the water meniscus on the side of the sample bottle for 
later determination of sample volume. Pour the entire sample into a 2-L 
separatory funnel. Check the pH of the sample with wide-range pH paper 
and adjust to within the range of 5 to 9 with sodium hydroxide solution 
or sulfuric acid.
    10.2  Add 60 mL of methylene chloride to the sample bottle, seal, 
and shake 30 s to rinse the inner surface. Transfer the solvent to the 
separatory funnel and extract the sample by shaking the funnel for 2 min 
with periodic venting to release excess pressure. Allow the organic 
layer to separate from the water phase for a minimum of 10 min. If the 
emulsion interface between layers is more than one-third the volume of 
the solvent layer, the analyst must employ mechanical techniques to 
complete the phase separation. The optimum technique depends upon the 
sample, but may include stirring, filtration of the emulsion through 
glass wool, centrifugation, or other physical methods. Collect the 
methylene chloride extract in a 250-mL Erlenmeyer flask.
    10.3  Add a second 60-mL volume of methylene chloride to the sample 
bottle and repeat the extraction procedure a second time, combining the 
extracts in the Erlenmeyer flask. Perform a third extraction in the same 
manner.
    10.4  Assemble a Kuderna-Danish (K-D) concentrator by attaching a 
10-mL concentrator tube to a 500-mL evaporative flask. Other 
concentration devices or techniques may be used in place of the K-D 
concentrator if the requirements of Section 8.2 are met.
    10.5  Add 10 mL of hydrochloric acid to the combined extracts and 
shake for 2 min. Allow the layers to separate. Pour the combined extract 
through a solvent-rinsed drying column containing about 10 cm of 
anhydrous sodium sulfate, and collect the extract in the K-D 
concentrator. Rinse the Erlenmeyer flask and column with 20 to 30 mL of 
methylene chloride to complete the quantitative transfer.
    10.6  Add one or two clean boiling chips to the evaporative flask 
and attach a three-ball Snyder column. Prewet the Snyder column by 
adding about 1 mL of methylene chloride to the top. Place the K-D 
apparatus on a hot water bath (60 to 65 deg.C) so that the concentrator 
tube is partially immersed in the hot water, and the entire lower 
rounded surface of the flask is bathed with hot vapor. Adjust the 
vertical position of the apparatus and the water temperature as required 
to complete the concentration in 15 to 20 min. At the proper rate of 
distillation the balls of the column will actively chatter but the 
chambers will not flood with condensed solvent. When the apparent volume 
of liquid reaches 1 mL, remove the K-D apparatus and allow it to drain 
and cool for at least 10 min.
    10.7  Remove the Snyder column and rinse the flask and its lower 
joint into the concentrator tube with 1 to 2 mL of methylene chloride. A 
5-mL syringe is recommended for this operation. Stopper the concentrator 
tube and store refrigerated if further processing will not be performed 
immediately. If the extract will be stored longer than two days, it 
should be transferred to a Teflon-sealed screw-cap vial. If N-
nitrosodiphenylamine is to be measured by gas chromatography, the 
analyst must first use a cleanup column to eliminate diphenylamine 
interference (Section 11). If N-nitrosodiphenylamine is of no interest, 
the analyst may proceed directly with gas chromatographic analysis 
(Section 12).

[[Page 106]]

    10.8  Determine the original sample volume by refilling the sample 
bottle to the mark and transferring the liquid to a 1000-
mL graduated cylinder. Record the sample volume to the nearest 5 mL.

                       11. Cleanup and Separation

    11.1  Cleanup procedures may not be necessary for a relatively clean 
sample matrix. If particular circumstances demand the use of a cleanup 
procedure, the analyst may use either procedure below or any other 
appropriate procedure. However, the analyst first must demonstrate that 
the requirements of Section 8.2 can be met using the method as revised 
to incorporate the cleanup procedure. Diphenylamine, if present in the 
original sample extract, must be separated from the nitrosamines if N-
nitrosodiphenylamine is to be determined by this method.
    11.2  If the entire extract is to be cleaned up by one of the 
following procedures, it must be concentrated to 2.0 mL. To the 
concentrator tube in Section 10.7, add a clean boiling chip and attach a 
two-ball micro-Snyder column. Prewet the column by adding about 0.5 mL 
of methylene chloride to the top. Place the micr-K-D apparatus on a hot 
water bath (60 to 65  deg.C) so that the concentrator tube is partially 
immersed in the hot water. Adjust the vertical position of the apparatus 
and the water temperature as required to complete the concentration in 5 
to 10 min. At the proper rate of distillation the balls of the column 
will actively chatter but the chambers will not flood. When the apparent 
volume of liquid reaches about 0.5 mL, remove the K-D apparatus and 
allow it to drain and cool for at least 10 min. Remove the micro-Snyder 
column and rinse its lower joint into the concentrator tube with 0.2 mL 
of methylene chloride. Adjust the final volume to 2.0 mL and proceed 
with one of the following cleanup procedures.
    11.3  Florisil column cleanup for nitrosamines:
    11.3.1  Place 22 g of activated Florisil into a 22-mm ID 
chromatographic column. Tap the column to settle the Florisil and add 
about 5 mm of anhydrous sodium sulfate to the top.
    11.3.2  Preelute the column with 40 mL of ethyl ether/pentane 
(15+85)(V/V). Discard the eluate and just prior to exposure of the 
sodium sulfate layer to the air, quantitatively transfer the 2-mL sample 
extract onto the column using an additional 2 mL of pentane to complete 
the transfer.
    11.3.3  Elute the column with 90 mL of ethyl ether/pentane 
(15+85)(V/V) and discard the eluate. This fraction will contain the 
diphenylamine, if it is present in the extract.
    11.3.4  Next, elute the column with 100 mL of acetone/ethyl ether 
(5+95)(V/V) into a 500-mL K-D flask equipped with a 10-mL concentrator 
tube. This fraction will contain all of the nitrosamines listed in the 
scope of the method.
    11.3.5  Add 15 mL of methanol to the collected fraction and 
concentrate as in Section 10.6, except use pentane to prewet the column 
and set the water bath at 70 to 75  deg.C. When the apparatus is cool, 
remove the Snyder column and rinse the flask and its lower joint into 
the concentrator tube with 1 to 2 mL of pentane. Analyze by gas 
chromatography (Section 12).
    11.4  Alumina column cleanup for nitrosamines:
    11.4.1  Place 12 g of the alumina preparation (Section 6.10) into a 
10-mm ID chromatographic column. Tap the column to settle the alumina 
and add 1 to 2 cm of anhydrous sodium sulfate to the top.
    11.4.2  Preelute the column with 10 mL of ethyl ether/pentane 
(3+7)(V/V). Discard the eluate (about 2 mL) and just prior to exposure 
of the sodium sulfate layer to the air, quantitatively transfer the 2 mL 
sample extract onto the column using an additional 2 mL of pentane to 
complete the transfer.
    11.4.3  Just prior to exposure of the sodium sulfate layer to the 
air, add 70 mL of ethyl ether/pentane (3+7)(V/V). Discard the first 10 
mL of eluate. Collect the remainder of the eluate in a 500-mL K-D flask 
equipped with a 10 mL concentrator tube. This fraction contains N-
nitrosodiphenylamine and probably a small amount of N-nitrosodi-n-
propylamine.
    11.4.4  Next, elute the column with 60 mL of ethyl ether/pentane 
(1+1)(V/V), collecting the eluate in a second K-D flask equipped with a 
10-mL concentrator tube. Add 15 mL of methanol to the K-D flask. This 
fraction will contain N-nitrosodimethylamine, most of the N-nitrosodi-n-
propylamine and any diphenylamine that is present.
    11.4.5  Concentrate both fractions as in Section 10.6, except use 
pentane to prewet the column. When the apparatus is cool, remove the 
Snyder column and rinse the flask and its lower joint into the 
concentrator tube with 1 to 2 mL of pentane. Analyze the fractions by 
gas chromatography (Section 12).

                         12. Gas Chromatography

    12.1  N-nitrosodiphenylamine completely reacts to form diphenylamine 
at the normal operating temperatures of a GC injection port (200 to 250  
deg.C). Thus, N-nitrosodiphenylamine is chromatographed and detected as 
diphenylamine. Accurate determination depends on removal of 
diphenylamine that may be present in the original extract prior to GC 
analysis (See Section 11).
    12.2  Table 1 summarizes the recommended operating conditions for 
the gas chromatograph. Included in this table are retention times and 
MDL that can be achieved under these conditions. Examples of the 
separations achieved by Column 1 are shown in

[[Page 107]]

Figures 1 and 2. Other packed or capillary (open-tubular) columns, 
chromatographic conditions, or detectors may be used if the requirements 
of Section 8.2 are met.
    12.3  Calibrate the system daily as described in Section 7.
    12.4  If the extract has not been subjected to one of the cleanup 
procedures in Section 11, it is necessary to exchange the solvent from 
methylene chloride to methanol before the thermionic detector can be 
used. To a 1 to 10-mL volume of methylene chloride extract in a 
concentrator tube, add 2 mL of methanol and a clean boiling chip. Attach 
a two-ball micro-Snyder column to the concentrator tube. Prewet the 
column by adding about 0.5 mL of methylene chloride to the top. Place 
the micro-K-D apparatus on a boiling (100  deg.C) water bath so that the 
concentrator tube is partially immersed in the hot water. Adjust the 
vertical position of the apparatus and the water temperature as required 
to complete the concentration in 5 to 10 min. At the proper rate of 
distillation the balls of the column will actively chatter but the 
chambers will not flood. When the apparent volume of liquid reaches 
about 0.5 mL, remove the K-D apparatus and allow it to drain and cool 
for at least 10 min. Remove the micro-Snyder column and rinse its lower 
joint into the concentrator tube with 0.2 mL of methanol. Adjust the 
final volume to 2.0 mL.
    12.5  If the internal standard calibration procedure is being used, 
the internal standard must be added to the sample extract and mixed 
thoroughly immediately before injection into the gas chromatograph.
    12.6  Inject 2 to 5 [mu]L of the sample extract or standard into the 
gas chromatograph using the solvent-flush technique.\21\ Smaller (1.0 
[mu]L) volumes may be injected if automatic devices are employed. Record 
the volume injected to the nearest 0.05 [mu]L, and the resulting peak 
size in area or peak height units.
    12.7  Identify the parameters in the sample by comparing the 
retention times of the peaks in the sample chromatogram with those of 
the peaks in standard chromatograms. The width of the retention time 
window used to make identifications should be based upon measurements of 
actual retention time variations of standards over the course of a day. 
Three times the standard deviation of a retention time for a compound 
can be used to calculate a suggested window size; however, the 
experience of the analyst should weigh heavily in the interpretation of 
chromatograms.
    12.8  If the response for a peak exceeds the working range of the 
system, dilute the extract and reanalyze.
    12.9  If the measurement of the peak response is prevented by the 
presence of interferences, further cleanup is required.

                            13. Calculations

    13.1  Determine the concentration of individual compounds in the 
sample.
    13.1.1  If the external standard calibration procedure is used, 
calculate the amount of material injected from the peak response using 
the calibration curve or calibration factor determined in Section 7.2.2. 
The concentration in the sample can be calculated from Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.105

                                                              Equation 2

where:
A=Amount of material injected (ng).
Vi=Volume of extract injected ([mu]L).
Vt=Volume of total extract ([mu]L).
Vs=Volume of water extracted (mL).

    13.1.2  If the internal standard calibration procedure is used, 
calculate the concentration in the sample using the response factor (RF) 
determined in Section 7.3.2 and Equation 3.
[GRAPHIC] [TIFF OMITTED] TC15NO91.106

                                                              Equation 3

where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Is=Amount of internal standard added to each extract ([mu]g).
Vo=Volume of water extracted (L).

    13.2  Report results in [mu]g/L without correction for recovery 
data. All QC data obtained should be reported with the sample results.

                         14. Method Performance

    14.1  The method detection limit (MDL) is defined as the minimum 
concentration of a substance that can be measured and reported with 99% 
confidence that the value is above zero.\3\ The MDL concentrations 
listed in Table 1 were obtained using reagent water.\22\ Similar results 
were achieved using representative wastewaters. The MDL actually 
achieved in a given analysis will vary depending on instrument 
sensitivity and matrix effects.
    14.2  This method has been tested for linearity of spike recovery 
from reagent water and has been demonstrated to be applicable over the 
concentration range from 4 x MDL to 1000 x MDL.\22\
    14.3  This method was tested by 17 laboratories using reagent water, 
drinking water, surface water, and three industrial wastewaters spiked 
at six concentrations

[[Page 108]]

over the range 0.8 to 55 [mu]g/L.\23\ Single operator precision, overall 
precision, and method accuracy were found to be directly related to the 
concentration of the parameter and essentially independent of the sample 
matrix. Linear equations to describe these relationships are presented 
in Table 3.

                               References

    1. Fine, D.H., Lieb, D., and Rufeh, R. ``Principle of Operation of 
the Thermal Energy Analyzer for the Trace Analysis of Volatile and Non-
volatile N-nitroso Compounds,'' Journal of Chromatography, 107, 351 
(1975).
    2. Fine, D.H., Hoffman, F., Rounbehler, D.P., and Belcher, N.M. 
``Analysis of N-nitroso Compounds by Combined High Performance Liquid 
Chromatography and Thermal Energy Analysis,'' Walker, E.A., Bogovski, P. 
and Griciute, L., Editors, N-nitroso Compounds--Analysis and Formation, 
Lyon, International Agency for Research on Cancer (IARC Scientific 
Publications No. 14), pp. 43-50 (1976).
    3. 40 CFR part 136, appendix B.
    4. ``Determination of Nitrosamines in Industrial and Municipal 
Wastewaters,'' EPA 600/4-82-016, National Technical Information Service, 
PB82-199621, Springfield, Virginia 22161, April 1982.
    5. ASTM Annual Book of Standards, Part 31, D3694-78. ``Standard 
Practices for Preparation of Sample Containers and for Preservation of 
Organic Constituents,'' American Society for Testing and Materials, 
Philadelphia.
    6. Buglass, A.J., Challis, B.C., and Osborn, M.R. ``Transnitrosation 
and Decomposition of Nitrosamines,'' Bogovski, P. and Walker, E.A., 
Editors, N-nitroso Compounds in the Environment, Lyon, International 
Agency for Research on Cancer (IARC Scientific Publication No. 9), pp. 
94-100 (1974).
    7. Burgess, E.M., and Lavanish, J.M. ``Photochemical Decomposition 
of N-nitrosamines,'' Tetrahedon Letters, 1221 (1964)
    8. Druckrey, H., Preussmann, R., Ivankovic, S., and Schmahl, D. 
``Organotrope Carcinogene Wirkungen bei 65 Verschiedenen N-
NitrosoVerbindungen an BD-Ratten,'' Z. Krebsforsch., 69, 103 (1967).
    9. Fiddler, W. ``The Occurrence and Determination of N-nitroso 
Compounds,'' Toxicol. Appl. Pharmacol., 31, 352 (1975).
    10. ``Carcinogens--Working With Carcinogens,'' Department of Health, 
Education, and Welfare, Public Health Service, Center for Disease 
Control, National Institute for Occupational Safety and Health, 
Publication No. 77-206, August 1977.
    11. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR 
Part 1910), Occupational Safety and Health Administration, OSHA 2206 
(Revised, January 1976).
    12. ``Safety in Academic Chemistry Laboratories,'' American Chemical 
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
    13. Lijinsky, W. ``How Nitrosamines Cause Cancer,'' New Scientist, 
73, 216 (1977).
    14. Mirvish, S.S. ``N-Nitroso compounds: Their Chemical and in vivo 
Formation and Possible Importance as Environmental Carcinogens,'' J. 
Toxicol. Environ. Health, 3, 1267 (1977).
    15. ``Reconnaissance of Environmental Levels of Nitrosamines in the 
Central United States,'' EPA-330/1-77-001, National Enforcement 
Investigations Center, U.S. Environmental Protection Agency (1977).
    16. ``Atmospheric Nitrosamine Assessment Report,'' Office of Air 
Quality Planning and Standards, U.S. Environmental Protection Agency, 
Research Triangle Park, North Carolina (1976).
    17. ``Scientific and Technical Assessment Report on Nitrosamines,'' 
EPA-660/6-7-001, Office of Research and Development, U.S. Environmental 
Protection Agency (1976).
    18. Provost, L.P., and Elder, R.S. ``Interpretation of Percent 
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44 
used in the equation in Section 8.3.3 is two times the value of 1.22 
derived in this report.)
    19. ASTM Annual Book of Standards, Part 31, D3370-76. ``Standard 
Practices for Sampling Water,'' American Society for Testing and 
Materials, Philadelphia.
    20. ``Methods 330.4 (Titrimetric, DPD-FAS) and 330.5 
(Spectrophotometric, DPD) for Chlorine, Total Residual,'' Methods for 
Chemical Analysis of Water and Wastes, EPA-600/4-79-020, U.S. 
Environmental Protection Agency, Environmental Monitoring and Support 
Laboratory, Cincinnati, Ohio 45268, March 1979.
    21. Burke, J. A. ``Gas Chromatography for Pesticide Residue 
Analysis; Some Practical Aspects,'' Journal of the Association of 
Official Analytical Chemists, 48, 1037 (1965).
    22. ``Method Detection Limit and Analytical Curve Studies EPA 
Methods 606, 607, and 608,'' Special letter report for EPA Contract 68-
03-2606, U.S. Environmental Protection Agency, Environmental Monitoring 
and Support Laboratory, Cincinnati, Ohio 45268, June 1980.
    23. ``EPA Method Study 17 Method 607--Nitrosamines,'' EPA 600/4-84-
051, National Technical Information Service, PB84-207646, Springfield, 
Virginia 22161, June 1984.

[[Page 109]]



     Table 1--Chromatographic Conditions and Method Detection Limits
------------------------------------------------------------------------
                                     Retention time (min)       Method
                                  --------------------------  detection
            Parameter                                           limit
                                     Column 1     Column 2    ([mu]g/L)
------------------------------------------------------------------------
N-Nitrosodimethylamine...........          4.1         0.88         0.15
N-Nitrosodi-n-propylamine........         12.1          4.2          .46
N-Nitrosodiphenylamine \a\.......     \b\ 12.8      \c\ 6.4          .81
------------------------------------------------------------------------
Column 1 conditions: Chromosorb W-AW (80/100 mesh) coated with 10%
  Carbowax 20 M/2% KOH packed in a 1.8 m long x 4mm ID glass column with
  helium carrier gas at 40 mL/min flow rate. Column temperature held
  isothermal at 110  deg.C, except where otherwise indicated.
Column 2 conditions: Supelcoport (100/120 mesh) coated with 10% SP-2250
  packed in a 1.8 m long x 4 mm ID glass column with helium carrier gas
  at 40 mL/min flow rate. Column temperature held isothermal at 120
  deg.C, except where otherwise indicated.
\a\ Measured as diphenylamine.
\b\ 220  deg.C column temperature.
\c\ 210  deg.C column temperature.


                                   Table 2--QC Acceptance Criteria--Method 607
----------------------------------------------------------------------------------------------------------------
                                                                                        Range for X   Range for
                          Parameter                            Test conc.  Limit for s   ([mu]g/L)      P, Ps
                                                               ([mu]g/L)    ([mu]g/L)                 (percent)
----------------------------------------------------------------------------------------------------------------
N-Nitrosodimethylamine......................................           20          3.4     4.6-20.0       13-109
N-Nitrosodiphenyl...........................................           20          6.1     2.1-24.5        D-139
N-Nitrosodi-n-propylamine...................................           20          5.7    11.5-26.8      45-146
----------------------------------------------------------------------------------------------------------------
s=Standard deviation for four recovery measurements, in [mu]g/L (Section 8.2.4).
X=Average recovery for four recovery measurements, in [mu]g/L (Section 8.2.4).
P, Ps=Percent recovery measured (Section 8.3.2, Section 8.4.2).
D=Detected; result must be greater than zero.
 
Note: These criteria are based directly upon the method performance data in Table 3. Where necessary, the limits
  for recovery have been broadened to assure applicability of the limits to concentrations below those used to
  develop Table 3.


                Table 3--Method Accuracy and Precision as Functions of Concentration--Method 607
----------------------------------------------------------------------------------------------------------------
                                                                   Accuracy, as   Single analyst      Overall
                            Parameter                              recovery, X'   precision, sr'   precision, S'
                                                                     ([mu]g/L)       ([mu]g/L)       ([mu]g/L)
----------------------------------------------------------------------------------------------------------------
N-Nitrosodimethylamine..........................................      0.37C+0.06      0.25X-0.04      0.25X+0.11
N-Nitrosodiphenylamine..........................................      0.64C+0.52      0.36X-1.53      0.46X-0.47
N-Nitrosodi-n-propylamine.......................................      0.96C-0.07      0.15X+0.13      0.21X+0.15
----------------------------------------------------------------------------------------------------------------
X'=Expected recovery for one or more measurements of a sample containing a concentration of C, in [mu]g/L.
sr'=Expected single analyst standard deviation of measurements at an average concentration found of X, in [mu]g/
  L.
S'=Expected interlaboratory standard deviation of measurements at an average concentration found of X, in [mu]g/
  L.
C=True value for the concentration, in [mu]g/L.
X=Average recovery found for measurements of samples containing a concentration of C, in [mu]g/L.


[[Page 110]]

[GRAPHIC] [TIFF OMITTED] TC02JY92.017


[[Page 111]]

[GRAPHIC] [TIFF OMITTED] TC02JY92.018


[[Page 112]]

             Method 608--Organochlorine Pesticides and PCBs

                        1. Scope and Application

    1.1  This method covers the determination of certain organochlorine 
pesticides and PCBs. The following parameters can be determined by this 
method:

------------------------------------------------------------------------
                  Parameter                    STORET No.      CAS No.
------------------------------------------------------------------------
Aldrin......................................         39330      309-00-2
[alpha]-BHC.................................         39337      319-84-6
[beta]-BHC..................................         39338      319-85-7
[delta]-BHC.................................         34259      319-86-8
[gamma]-BHC.................................         39340       58-89-9
Chlordane...................................         39350       57-74-9
4,4'-DDD....................................         39310       72-54-8
4,4'-DDE....................................         39320       72-55-9
4,4'-DDT....................................         39300       50-29-3
Dieldrin....................................         39380       60-57-1
Endosulfan I................................         34361      959-98-8
Endosulfan II...............................         34356    33212-65-9
Endosulfan sulfate..........................         34351     1031-07-8
Eldrin......................................         39390       72-20-8
Endrin aldehyde.............................         34366     7421-93-4
Heptachlor..................................         39410       76-44-8
Heptachlor epoxide..........................         39420     1024-57-3
Toxaphene...................................         39400     8001-35-2
PCB-1016....................................         34671    12674-11-2
PCB-1221....................................         39488     1104-28-2
PCB-1232....................................         39492    11141-16-5
PCB-1242....................................         39496    53469-21-9
PCB-1248....................................         39500    12672-29-6
PCB-1254....................................         39504    11097-69-1
PCB-1260....................................         39508    11096-82-5
------------------------------------------------------------------------

    1.2  This is a gas chromatographic (GC) method applicable to the 
determination of the compounds listed above in municipal and industrial 
discharges as provided under 40 CFR 136.1. When this method is used to 
analyze unfamiliar samples for any or all of the compounds above, 
compound identifications should be supported by at least one additional 
qualitative technique. This method describes analytical conditions for a 
second gas chromatographic column that can be used to confirm 
measurements made with the primary column. Method 625 provides gas 
chromatograph/mass spectrometer (GC/MS) conditions appropriate for the 
qualitative and quantitative confirmation of results for all of the 
parameters listed above, using the extract produced by this method.
    1.3  The method detection limit (MDL, defined in Section 14.1)\1\ 
for each parameter is listed in Table 1. The MDL for a specific 
wastewater may differ from those listed, depending upon the nature of 
interferences in the sample matrix.
    1.4  The sample extraction and concentration steps in this method 
are essentially the same as in Methods 606, 609, 611, and 612. Thus, a 
single sample may be extracted to measure the parameters included in the 
scope of each of these methods. When cleanup is required, the 
concentration levels must be high enough to permit selecting aliquots, 
as necessary, to apply appropriate cleanup procedures. The analyst is 
allowed the latitude, under Section 12, to select chromatographic 
conditions appropriate for the simultaneous measurement of combinations 
of these parameters.
    1.5  Any modification of this method, beyond those expressly 
permitted, shall be considered as a major modification subject to 
application and approval of alternate test procedures under 40 CFR 136.4 
and 136.5.
    1.6  This method is restricted to use by or under the supervision of 
analysts experienced in the use of a gas chromatograph and in the 
interpretation of gas chromatograms. Each analyst must demonstrate the 
ability to generate acceptable results with this method using the 
procedure described in Section 8.2.

                          2. Summary of Method

    2.1  A measured volume of sample, approximately 1-L, is extracted 
with methylene chloride using a separatory funnel. The methylene 
chloride extract is dried and exchanged to hexane during concentration 
to a volume of 10 mL or less. The extract is separated by gas 
chromatography and the parameters are then measured with an electron 
capture detector.\2\
    2.2  The method provides a Florisil column cleanup procedure and an 
elemental sulfur removal procedure to aid in the elimination of 
interferences that may be encountered.

                            3. Interferences

    3.1  Method interferences may be caused by contaminants in solvents, 
reagents, glassware, and other sample processing hardware that lead to 
discrete artifacts and/or elevated baselines in gas chromatograms. All 
of these materials must be routinely demonstrated to be free from 
interferences under the conditions of the analysis by running laboratory 
reagent blanks as described in Section 8.1.3.
    3.1.1  Glassware must be scrupulously cleaned.\3\ Clean all 
glassware as soon as possible after use by rinsing with the last solvent 
used in it. Solvent rinsing should be followed by detergent washing with 
hot water, and rinses with tap water and distilled water. The glassware 
should then be drained dry, and heated in a muffle furnace at 400  deg.C 
for 15 to 30 min. Some thermally stable materials, such as PCBs, may not 
be eliminated by this treatment. Solvent rinses with acetone and 
pesticide quality hexane may be substituted for the muffle furnace 
heating. Thorough rinsing with such solvents usually eliminates PCB 
interference. Volumetric ware should not be heated in a muffle furnace. 
After drying and cooling, glassware should be sealed and stored in a 
clean environment to prevent any accumulation of dust or other 
contaminants. Store inverted or capped with aluminum foil.

[[Page 113]]

    3.1.2  The use of high purity reagents and solvents helps to 
minimize interference problems. Purification of solvents by distillation 
in all-glass systems may be required.
    3.2  Interferences by phthalate esters can pose a major problem in 
pesticide analysis when using the electron capture detector. These 
compounds generally appear in the chromatogram as large late eluting 
peaks, especially in the 15 and 50% fractions from Florisil. Common 
flexible plastics contain varying amounts of phthalates. These 
phthalates are easily extracted or leached from such materials during 
laboratory operations. Cross contamination of clean glassware routinely 
occurs when plastics are handled during extraction steps, especially 
when solvent-wetted surfaces are handled. Interferences from phthalates 
can best be minimized by avoiding the use of plastics in the laboratory. 
Exhaustive cleanup of reagents and glassware may be required to 
eliminate background phthalate contamination.4, 5 The 
interferences from phthalate esters can be avoided by using a 
microcoulometric or electrolytic conductivity detector.
    3.3  Matrix interferences may be caused by contaminants that are co-
extracted from the sample. The extent of matrix interferences will vary 
considerably from source to source, depending upon the nature and 
diversity of the industrial complex or municipality being sampled. The 
cleanup procedures in Section 11 can be used to overcome many of these 
interferences, but unique samples may require additional cleanup 
approaches to achieve the MDL listed in Table 1.

                                4. Safety

    4.1  The toxicity or carcinogenicity of each reagent used in this 
method has not been precisely defined; however, each chemical compound 
should be treated as a potential health hazard. From this viewpoint, 
exposure to these chemicals must be reduced to the lowest possible level 
by whatever means available. The laboratory is responsible for 
maintaining a current awareness file of OSHA regulations regarding the 
safe handling of the chemicals specified in this method. A reference 
file of material data handling sheets should also be made available to 
all personnel involved in the chemical analysis. Additional references 
to laboratory safety are available and have been identified 
6-8 for the information of the analyst.
    4.2  The following parameters covered by this method have been 
tentatively classified as known or suspected, human or mammalian 
carcinogens: 4,4'-DDT, 4,4'-DDD, the BHCs, and the PCBs. Primary 
standards of these toxic compounds should be prepared in a hood. A 
NIOSH/MESA approved toxic gas respirator should be worn when the analyst 
handles high concentrations of these toxic compounds.

                       5. Apparatus and Materials

    5.1  Sampling equipment, for discrete or composite sampling.
    5.1.1  Grab sample bottle--1-L or 1-qt, amber glass, fitted with a 
screw cap lined with Teflon. Foil may be substituted for Teflon if the 
sample is not corrosive. If amber bottles are not available, protect 
samples from light. The bottle and cap liner must be washed, rinsed with 
acetone or methylene chloride, and dried before use to minimize 
contamination.
    5.1.2  Automatic sampler (optional)--The sampler must incorporate 
glass sample containers for the collection of a minimum of 250 mL of 
sample. Sample containers must be kept refrigerated at 4  deg.C and 
protected from light during composting. If the sampler uses a 
peristaltic pump, a minimum length of compressible silicone rubber 
tubing may be used. Before use, however, the compressible tubing should 
be thoroughly rinsed with methanol, followed by repeated rinsings with 
distilled water to minimize the potential for contamination of the 
sample. An integrating flow meter is required to collect flow 
proportional composites.
    5.2.  Glassware (All specifications are suggested. Catalog numbers 
are included for illustration only.):
    5.2.1  Separatory funnel--2-L, with Teflon stopcock.
    5.2.2  Drying column--Chromatographic column, approximately 400 mm 
long x 19 mm ID, with coarse frit filter disc.
    5.2.3  Chromatographic column--400 mm long x 22 mm ID, with Teflon 
stopcock and coarse frit filter disc (Kontes K-42054 or equivalent).
    5.2.4  Concentrator tube, Kuderna-Danish--10-mL, graduated (Kontes 
K-570050-1025 or equivalent). Calibration must be checked at the volumes 
employed in the test. Ground glass stopper is used to prevent 
evaporation of extracts.
    5.2.5  Evaporative flask, Kuderna-Danish--500-mL (Kontes K-570001-
0500 or equivalent). Attach to concentrator tube with springs.
    5.2.6  Snyder column, Kuderna/Danish--Three-ball macro (Kontes K-
503000-0121 or equivalent).
    5.2.7  Vials--10 to 15-mL, amber glass, with Teflon-lined screw cap.
    5.3  Boiling chips--Approximately 10/40 mesh. Heat to 400  deg.C for 
30 min or Soxhlet extract with methylene chloride.
    5.4  Water bath--Heated, with concentric ring cover, capable of 
temperature control (2  deg.C). The bath should be used in a 
hood.
    5.5  Balance--Analytical, capable of accurately weighing 0.0001 g.
    5.6  Gas chromatograph--An analytical system complete with gas 
chromatograph suitable for on-column injection and all required 
accessories including syringes, analytical columns, gases, detector, and 
strip-

[[Page 114]]

chart recorder. A data system is recommended for measuring peak areas.
    5.6.1  Column 1--1.8 m long x 4 mm ID glass, packed with 1.5% SP-
2250/1.95% SP-2401 on Supelcoport (100/120 mesh) or equivalent. This 
column was used to develop the method performance statements in Section 
14. Guidelines for the use of alternate column packings are provided in 
Section 12.1.
    5.6.2  Column 2--1.8 m long x 4 mm ID glass, packed with 3% OV-1 on 
Supelcoport (100/120 mesh) or equivalent.
    5.6.3  Detector--Electron capture detector. This detector has proven 
effective in the analysis of wastewaters for the parameters listed in 
the scope (Section 1.1), and was used to develop the method performance 
statements in Section 14. Guidelines for the use of alternate detectors 
are provided in Section 12.1.

                               6. Reagents

    6.1  Reagent water--Reagent water is defined as a water in which an 
interferent is not observed at the MDL of the parameters of interest.
    6.2  Sodium hydroxide solution (10 N)--Dissolve 40 g of NaOH (ACS) 
in reagent water and dilute to 100 mL.
    6.3  Sodium thiosulfate--(ACS) Granular.
    6.4  Sulfuric acid (1+1)--Slowly, add 50 mL to 
H2SO4 (ACS, sp. gr. 1.84) to 50 mL of reagent 
water.
    6.5  Acetone, hexane, isooctane, methylene chloride--Pesticide 
quality or equivalent.
    6.6  Ethyl ether--Nanograde, redistilled in glass if necessary.
    6.6.1  Ethyl ether must be shown to be free of peroxides before it 
is used as indicated by EM Laboratories Quant test strips. (Available 
from Scientific Products Co., Cat. No. P1126-8, and other suppliers.)
    6.6.2  Procedures recommended for removal of peroxides are provided 
with the test strips. After cleanup, 20 mL of ethyl alcohol preservative 
must be added to each liter of ether.
    6.7  Sodium sulfate--(ACS) Granular, anhydrous. Purify by heating at 
400  deg.C for 4 h in a shallow tray.
    6.8  Florisil--PR grade (60/100 mesh). Purchase activated at 1250 
deg.F and store in the dark in glass containers with ground glass 
stoppers or foil-lined screw caps. Before use, activate each batch at 
least 16 h at 130  deg.C in a foil-covered glass container and allow to 
cool.
    6.9  Mercury--Triple distilled.
    6.10  Copper powder--Activated.
    6.11  Stock standard solutions (1.00 [mu]g/[mu]L)--Stock standard 
solutions can be prepared from pure standard materials or purchased as 
certified solutions.
    6.11.1  Prepare stock standard solutions by accurately weighing 
about 0.0100 g of pure material. Dissolve the material in isooctane and 
dilute to volume in a 10-mL volumetric flask. Larger volumes can be used 
at the convenience of the analyst. When compound purity is assayed to be 
96% or greater, the weight can be used without correction to calculate 
the concentration of the stock standard. Commercially prepared stock 
standards can be used at any concentration if they are certified by the 
manufacturer or by an independent source.
    6.11.2  Transfer the stock standard solutions into Teflon-sealed 
screw-cap bottles. Store at 4  deg.C and protect from light. Stock 
standard solutions should be checked frequently for signs of degradation 
or evaporation, especially just prior to preparing calibration standards 
from them.
    6.11.3  Stock standard solutions must be replaced after six months, 
or sooner if comparison with check standards indicates a problem.
    6.12  Quality control check sample concentrate--See Section 8.2.1.

                             7. Calibration

    7.1  Establish gas chromatographic operating conditions equivalent 
to those given in Table 1. The gas chromatographic system can be 
calibrated using the external standard technique (Section 7.2) or the 
internal standard technique (Section 7.3).
    7.2  External standard calibration procedure:
    7.2.1  Prepare calibration standards at a minimum of three 
concentration levels for each parameter of interest by adding volumes of 
one or more stock standards to a volumetric flask and diluting to volume 
with isooctane. One of the external standards should be at a 
concentration near, but above, the MDL (Table 1) and the other 
concentrations should correspond to the expected range of concentrations 
found in real samples or should define the working range of the 
detector.
    7.2.2  Using injections of 2 to 5 [mu]L, analyze each calibration 
standard according to Section 12 and tabulate peak height or area 
responses against the mass injected. The results can be used to prepare 
a calibration curve for each compound. Alternatively, if the ratio of 
response to amount injected (calibration factor) is a constant over the 
working range (<10% relative standard deviation, RSD), linearity through 
the origin can be assumed and the average ratio or calibration factor 
can be used in place of a calibration curve.
    7.3  Internal standard calibration procedure--To use this approach, 
the analyst must select one or more internal standards that are similar 
in analytical behavior to the compounds of interest. The analyst must 
further demonstrate that the measurement of the internal standard is not 
affected by method or matrix interferences. Because of these 
limitations, no internal standard can

[[Page 115]]

be suggested that is applicable to all samples.
    7.3.1  Prepare calibration standards at a minimum of three 
concentration levels for each parameter of interest by adding volumes of 
one or more stock standards to a volumetric flask. To each calibration 
standard, add a known constant amount of one or more internal standards, 
and dilute to volume with isooctane. One of the standards should be at a 
concentration near, but above, the MDL and the other concentrations 
should correspond to the expected range of concentrations found in real 
samples or should define the working range of the detector.
    7.3.2  Using injections of 2 to 5 [mu]L, analyze each calibration 
standard according to Section 12 and tabulate peak height or area 
responses against concentration for each compound and internal standard. 
Calculate response factors (RF) for each compound using Equation 1.
[GRAPHIC] [TIFF OMITTED] TC15NO91.107

                                                              Equation 1
where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Cis=Concentration of the internal standard ([mu]g/L).
Cs=Concentraton of the parameter to be measured ([mu]g/L).

    If the RF value over the working range is a constant (<10% RSD), the 
RF can be assumed to be invariant and the average RF can be used for 
calculations. Alternatively, the results can be used to plot a 
calibration curve of response ratios, As/Ais, vs. 
RF.
    7.4  The working calibration curve, calibration factor, or RF must 
be verified on each working day by the measurement of one or more 
calibration standards. If the response for any parameter varies from the 
predicted response by more than 15%, the test must be 
repeated using a fresh calibration standard. Alternatively, a new 
calibration curve must be prepared for that compound.
    7.5  The cleanup procedure in Section 11 utilizes Florisil column 
chromatography. Florisil from different batches or sources may vary in 
adsorptive capacity. To standardize the amount of Florisil which is 
used, the use of lauric acid value \9\ is suggested. The referenced 
procedure determines the adsorption from hexane solution of lauric acid 
(mg) per g of Florisil. The amount of Florisil to be used for each 
column is calculated by dividing 110 by this ratio and multiplying by 20 
g.
    7.6  Before using any cleanup procedure, the analyst must process a 
series of calibration standards through the procedure to validate 
elution patterns and the absence of interferences from the reagents.

                           8. Quality Control

    8.1  Each laboratory that uses this method is required to operate a 
formal quality control program. The minimum requirements of this program 
consist of an initial demonstration of laboratory capability and an 
ongoing analysis of spiked samples to evaluate and document data 
quality. The laboratory must maintain records to document the quality of 
data that is generated. Ongoing data quality checks are compared with 
established performance criteria to determine if the results of analyses 
meet the performance characteristics of the method. When results of 
sample spikes indicate atypical method performance, a quality control 
check standard must be analyzed to confirm that the measurements were 
performed in an in-control mode of operation.
    8.1.1  The analyst must make an initial, one-time, demonstration of 
the ability to generate acceptable accuracy and precision with this 
method. This ability is established as described in Section 8.2.
    8.1.2  In recognition of advances that are occurring in 
chromatography, the analyst is permitted certain options (detailed in 
Sections 10.4, 11.1, and 12.1) to improve the separations or lower the 
cost of measurements. Each time such a modification is made to the 
method, the analyst is required to repeat the procedure in Section 8.2.
    8.1.3  Before processing any samples, the analyst must analyze a 
reagent water blank to demonstrate that interferences from the 
analytical system and glassware are under control. Each time a set of 
samples is extracted or reagents are changed, a reagent water blank must 
be processed as a safeguard against laboratory contamination.
    8.1.4  The laboratory must, on an ongoing basis, spike and analyze a 
minimum of 10% of all samples to monitor and evaluate laboratory data 
quality. This procedure is described in Section 8.3.
    8.1.5  The laboratory must, on an ongoing basis, demonstrate through 
the analyses of quality control check standards that the operation of 
the measurement system is in control. This procedure is described in 
Section 8.4. The frequency of the check standard analyses is equivalent 
to 10% of all samples analyzed but may be reduced if spike recoveries 
from samples (Section 8.3) meet all specified quality control criteria.
    8.1.6  The laboratory must maintain performance records to document 
the quality of data that is generated. This procedure is described in 
Section 8.5.
    8.2  To establish the ability to generate acceptable accuracy and 
precision, the analyst must perform the following operations.

[[Page 116]]

    8.2.1  A quality control (QC) check sample concentrate is required 
containing each single-component parameter of interest at the following 
concentrations in acetone: 4,4'-DDD, 10 [mu]g/mL; 4,4'-DDT, 10 [mu]g/mL; 
endosulfan II, 10 [mu]g/mL; endosulfan sulfate, 10 [mu]g/mL; endrin, 10 
[mu]g/mL; any other single-component pesticide, 2 [mu]g/mL. If this 
method is only to be used to analyze for PCBs, chlordane, or toxaphene, 
the QC check sample concentrate should contain the most representative 
multicomponent parameter at a concentration of 50 [mu]g/mL in acetone. 
The QC check sample concentrate must be obtained from the U.S. 
Environmental Protection Agency, Environmental Monitoring and Support 
Laboratory in Cincinnati, Ohio, if available. If not available from that 
source, the QC check sample concentrate must be obtained from another 
external source. If not available from either source above, the QC check 
sample concentrate must be prepared by the laboratory using stock 
standards prepared independently from those used for calibration.
    8.2.2  Using a pipet, prepare QC check samples at the test 
concentrations shown in Table 3 by adding 1.00 mL of QC check sample 
concentrate to each of four 1-L aliquots of reagent water.
    8.2.3  Analyze the well-mixed QC check samples according to the 
method beginning in Section 10.
    8.2.4  Calculate the average recovery (X) in [mu]g/mL; and the 
standard deviation of the recovery (s) in [mu]g/mL, for each parameter 
using the four results.
    8.2.5  For each parameter compare s and X with the corresponding 
acceptance criteria for precision and accuracy, respectively, found in 
Table 3. If s and X for all parameters of interest meet the acceptance 
criteria, the system performance is acceptable and analysis of actual 
samples can begin. If any individual s exceeds the precision limit or 
any individual X falls outside the range for accuracy, the system 
performance is unacceptable for that parameter.
    Note: The large number of parameters in Table 3 present a 
substantial probability that one or more will fail at least one of the 
acceptance criteria when all parameters are analyzed.
    8.2.6  When one or more of the parameters tested fail at least one 
of the acceptance criteria, the analyst must proceed according to 
Section 8.2.6.1 or 8.2.6.2.
    8.2.6.1  Locate and correct the source of the problem and repeat the 
test for all parameters of interest beginning with Section 8.2.2.
    8.2.6.2  Beginning with Section 8.2.2, repeat the test only for 
those parameters that failed to meet criteria. Repeated failure, 
however, will confirm a general problem with the measurement system. If 
this occurs, locate and correct the source of the problem and repeat the 
test for all compmunds of interest beginning with Section 8.2.2.
    8.3  The laboratory must, on an ongoing basis, spike at least 10% of 
the samples from each sample site being monitored to assess accuracy. 
For laboratories analyzing one to ten samples per month, at least one 
spiked sample per month is required.
    8.3.1  The concentration of the spike in the sample should be 
determined as follows:
    8.3.1.1  If, as in compliance monitoring, the concentration of a 
specific parameter in the sample is being checked against a regulatory 
concentration limit, the spike should be at that limit or 1 to 5 times 
higher than the background concentration determined in Section 8.3.2, 
whichever concentration would be larger.
    8.3.1.2  If the concentration of a specific parameter in the sample 
is not being checked against a limit specific to that parameter, the 
spike should be at the test concentration in Section 8.2.2 or 1 to 5 
times higher than the background concentration determined in Section 
8.3.2, whichever concentration would be larger.
    8.3.1.3  If it is impractical to determine background levels before 
spiking (e.g., maximum holding times will be exceeded), the spike 
concentration should be (1) the regulatory concentration limit, if any; 
or, if none (2) the larger of either 5 times higher than the expected 
background concentration or the test concentration in Section 8.2.2.
    8.3.2  Analyze one sample aliquot to determine the background 
concentration (B) of each parameter. If necessary, prepare a new QC 
check sample concentrate (Section 8.2.1) appropriate for the background 
concentrations in the sample. Spike a second sample aliquot with 1.0 mL 
of the QC check sample concentrate and analyze it to determine the 
concentration after spiking (A) of each parameter. Calculate each 
percent recovery (P) as 100(A-B)%/T, where T is the known true value of 
the spike.
    8.3.3  Compare the percent recovery (P) for each parameter with the 
corresponding QC acceptance criteria found in Table 3. These acceptance 
criteria were calculated to include an allowance for error in 
measurement of both the background and spike concentrations, assuming a 
spike to background ratio of 5:1. This error will be accounted for to 
the extent that the analyst's spike to background ratio approaches 
5:1.\10\ If spiking was performed at a concentration lower than the test 
concentration in Section 8.2.2, the analyst must use either the QC 
acceptance criteria in Table 3, or optional QC acceptance criteria 
calculated for the specific spike concentration. To calculate optional 
acceptance criteria for the recovery of a parameter: (1) Calculate 
accuracy (X') using the equation in Table 4, substituting the spike 
concentration (T) for C; (2) calculate overall precision (S') using the 
equation in Table 4, substituting X'

[[Page 117]]

for X; (3) calculate the range for recovery at the spike concentration 
as (100 X'/T)2.44(100 S'/T)%.\10\
    8.3.4  If any individual P falls outside the designated range for 
recovery, that parameter has failed the acceptance criteria. A check 
standard containing each parameter that failed the criteria must be 
analyzed as described in Section 8.4.
    8.4  If any parameter fails the acceptance criteria for recovery in 
Section 8.3, a QC check standard containing each parameter that failed 
must be prepared and analyzed.
    Note: The frequency for the required analysis of a QC check standard 
will depend upon the number of parameters being simultaneously tested, 
the complexity of the sample matrix, and the performance of the 
laboratory. If the entire list of parameters in Table 3 must be measured 
in the sample in Section 8.3, the probability that the analysis of a QC 
check standard will be required is high. In this case the QC check 
standard should be routinely analyzed with the spike sample.
    8.4.1  Prepare the QC check standard by adding 1.0 mL of QC check 
sample concentrate (Section 8.2.1 or 8.3.2) to 1 L of reagent water. The 
QC check standard needs only to contain the parameters that failed 
criteria in the test in Section 8.3.
    8.4.2  Analyze the QC check standards to determine the concentration 
measured (A) of each parameter. Calculate each percent recovery 
(Ps) as 100 (A/T)%, where T is the true value of the standard 
concentration.
    8.4.3  Compare the percent recovery (Ps) for each 
parameter with the corresponding QC acceptance criteria found in Table 
3. Only parameters that failed the test in Section 8.3 need to be 
compared with these criteria. If the recovery of any such parameter 
falls outside the designated range, the laboratory performance for that 
parameter is judged to be out of control, and the problem must be 
immediately identified and corrected. The analytical result for that 
parameter in the unspiked sample is suspect and may not be reported for 
regulatory compliance purposes.
    8.5  As part of the QC program for the laboratory, method accuracy 
for wastewater samples must be assessed and records must be maintained. 
After the analysis of five spiked wastewater samples as in Section 8.3, 
calculate the average percent recovery (P) and the standard deviation of 
the percent recovery (sp). Express the accuracy assessment as 
a percent recovery interval from P-2 sp to P+2 sp. 
If P=90% and sp=10%, for example, the accuracy interval is 
expressed as 70-110%. Update the accuracy assessment for each parameter 
on a regular basis (e.g. after each five to ten new accuracy 
measurements).
    8.6  It is recommended that the laboratory adopt additional quality 
assurance practices for use with this method. The specific practices 
that are most productive depend upon the needs of the laboratory and the 
nature of the samples. Field duplicates may be analyzed to assess the 
precision of the environmental measurements. When doubt exists over the 
identification of a peak on the chromatogram, confirmatory techniques 
such as gas chromatography with a dissimilar column, specific element 
detector, or mass spectrometer must be used. Whenever possible, the 
laboratory should analyze standard reference materials and participate 
in relevant performance evaluation studies.

            9. Sample Collection, Preservation, and Handling

    9.1  Grab samples must be collected in glass containers. 
Conventional sampling practices \11\ should be followed, except that the 
bottle must not be prerinsed with sample before collection. Composite 
samples should be collected in refrigerated glass containers in 
accordance with the requirements of the program. Automatic sampling 
equipment must be as free as possible of Tygon tubing and other 
potential sources of contamination.
    9.2  All samples must be iced or refrigerated at 4  deg.C from the 
time of collection until extraction. If the samples will not be 
extracted within 72 h of collection, the sample should be adjusted to a 
pH range of 5.0 to 9.0 with sodium hydroxide solution or sulfuric acid. 
Record the volume of acid or base used. If aldrin is to be determined, 
add sodium thiosulfate when residual chlorine is present. EPA Methods 
330.4 and 330.5 may be used for measurement of residual chlorine.\12\ 
Field test kits are available for this purpose.
    9.3  All samples must be extracted within 7 days of collection and 
completely analyzed within 40 days of extraction.\2\

                          10. Sample Extraction

    10.1  Mark the water meniscus on the side of the sample bottle for 
later determination of sample volume. Pour the entire sample into a 2-L 
separatory funnel.
    10.2  Add 60 mL of methylene chloride to the sample bottle, seal, 
and shake 30 s to rinse the inner surface. Transfer the solvent to the 
separatory funnel and extract the sample by shaking the funnel for 2 
min. with periodic venting to release excess pressure. Allow the organic 
layer to separate from the water phase for a minimum of 10 min. If the 
emulsion interface between layers is more than one-third the volume of 
the solvent layer, the analyst must employ mechanical techniques to 
complete the phase separation. The optium technique depends upon the 
sample, but may include stirring, filtration of the emulsion through 
glass wool, centrifugation, or other physical methods. Collect the 
methylene chloride extract in a 250-mL Erlenmeyer flask.

[[Page 118]]

    10.3  Add a second 60-mL volume of methylene chloride to the sample 
bottle and repeat the extraction procedure a second time, combining the 
extracts in the Erlenmeyer flask. Perform a third extraction in the same 
manner.
    10.4  Assemble a Kuderna-Danish (K-D) concentrator by attaching a 
10-mL concentrator tube to a 500-mL evaporative flask. Other 
concentration devices or techniques may be used in place of the K-D 
concentrator if the requirements of Section 8.2 are met.
    10.5  Pour the combined extract through a solvent-rinsed drying 
column containing about 10 cm of anhydrous sodium sulfate, and collect 
the extract in the K-D concentrator. Rinse the Erlenmeyer flask and 
column with 20 to 30 mL of methylene chloride to complete the 
quantitative transfer.
    10.6  Add one or two clean boiling chips to the evaporative flask 
and attach a three-ball Snyder column. Prewet the Snyder column by 
adding about 1 mL of methylene chloride to the top. Place the K-D 
apparatus on a hot water bath (60 to 65  deg.C) so that the concentrator 
tube is partially immersed in the hot water, and the entire lower 
rounded surface of the flask is bathed with hot vapor. Adjust the 
vertical position of the apparatus and the water temperature as required 
to complete the concentration in 15 to 20 min. At the proper rate of 
distillation the balls of the column will actively chatter but the 
chambers will not flood with condensed solvent. When the apparent volume 
of liquid reaches 1 mL, remove the K-D apparatus and allow it to drain 
and cool for at least 10 min.
    10.7  Increase the temperature of the hot water bath to about 80 
deg.C. Momeltarily remove the Snyder column, add 50 mL of hexane and a 
new boiling chip, and reattach the Snyder column. Concentrate the 
extract as in Section 10.6, except use hexane to prewet the column. The 
elapsed time of concentration should be 5 to 10 min.
    10.8  Remove the Snyder column and rinse the flask and its lower 
joint into the concentrator tube with 1 to 2 mL of hexane. A 5-mL 
syringe is recommended for this operation. Stopper the concentrator tube 
and store refrigerated if further processing will not be performed 
immediately. If the extract will be stored longer than two days, it 
should be transferred to a Teflon-sealed screw-cap vial. If the sample 
extract requires no further cleanup, proceed with gas chromatographic 
analysis (Section 12). If the sample requires further cleanup, proceed 
to Section 11.
    10.9  Determine the original sample volume by refilling the sample 
bottle to the mark and transferring the liquid to a 1000-mL graduated 
cylinder. Record the sample volume to the nearest 5 mL.

                       11. Cleanup and Separation

    11.1  Cleanup procedures may not be necessary for a relatively clean 
sample matrix. If particular circumstances demand the use of a cleanup 
procedure, the analyst may use either procedure below or any other 
appropriate procedure. However, the analyst first must demonstrate that 
the requirements of Section 8.2 can be met using the method as revised 
to incorporate the cleanup procedure. The Florisil column allows for a 
select fractionation of the compounds and will eliminate polar 
interferences. Elemental sulfur, which interferes with the electron 
capture gas chromatography of certain pesticides, can be removed by the 
technique described in Section 11.3.
    11.2  Florisil column cleanup:
    11.2.1  Place a weight of Florisil (nominally 20 g) predetermined by 
calibration (Section 7.5), into a chromatographic column. Tap the column 
to settle the Florisil and add 1 to 2 cm of anhydrous sodium sulfate to 
the top.
    11.2.2  Add 60 mL of hexane to wet and rinse the sodium sulfate and 
Florisil. Just prior to exposure of the sodium sulfate layer to the air, 
stop the elution of the hexane by closing the stopcock on the 
chromatographic column. Discard the eluate.
    11.2.3  Adjust the sample extract volume to 10 mL with hexane and 
transfer it from the K-D concentrator tube onto the column. Rinse the 
tube twice with 1 to 2 mL of hexane, adding each rinse to the column.
    11.2.4  Place a 500-mL K-D flask and clean concentrator tube under 
the chromatographic column. Drain the column into the flask until the 
sodium sulfate layer is nearly exposed. Elute the column with 200 mL of 
6% ethyl ether in hexane (V/V) (Fraction 1) at a rate of about 5 mL/min. 
Remove the K-D flask and set it aside for later concentration. Elute the 
column again, using 200 mL of 15% ethyl ether in hexane (V/V) (Fraction 
2), into a second K-D flask. Perform the third elution using 200 mL of 
50% ethyl ether in hexane (V/V) (Fraction 3). The elution patterns for 
the pesticides and PCBs are shown in Table 2.
    11.2.5  Concentrate the fractions as in Section 10.6, except use 
hexane to prewet the column and set the water bath at about 85  deg.C. 
When the apparatus is cool, remove the Snyder column and rinse the flask 
and its lower joint into the concentrator tube with hexane. Adjust the 
volume of each fraction to 10 mL with hexane and analyze by gas 
chromatography (Section 12).
    11.3  Elemental sulfur will usually elute entirely in Fraction 1 of 
the Florisil column cleanup. To remove sulfur interference from this 
fraction or the original extract, pipet 1.00 mL of the concentrated 
extract into a clean concentrator tube or Teflon-sealed vial. Add one to 
three drops of mercury and

[[Page 119]]

seal.\13\ Agitate the contents of the vial for 15 to 30 s. Prolonged 
shaking (2 h) may be required. If so, this may be accomplished with a 
reciprocal shaker. Alternatively, activated copper powder may be used 
for sulfur removal.\14\ Analyze by gas chromatography.

                         12. Gas Chromatography

    12.1  Table 1 summarizes the recommended operating conditions for 
the gas chromatograph. Included in this table are retention times and 
MDL that can be achieved under these conditions. Examples of the 
separations achieved by Column 1 are shown in Figures 1 to 10. Other 
packed or capillary (open-tubular) columns, chromatographic conditions, 
or detectors may be used if the requirements of Section 8.2 are met.
    12.2  Calibrate the system daily as described in Section 7.
    12.3  If the internal standard calibration procedure is being used, 
the internal standard must be added to the sample extract and mixed 
thoroughly immediately before injection into the gas chromatograph.
    12.4  Inject 2 to 5 [mu]L of the sample extract or standard into the 
gas chromatograph using the solvent-flush technique.\15\ Smaller (1.0 
uL) volumes may be injected if automatic devices are employed. Record 
the volume injected to the nearest 0.05 [mu]L, the total extract volume, 
and the resulting peak size in area or peak height units.
    12.5  Identify the parameters in the sample by comparing the 
retention times of the peaks in the sample chromatogram with those of 
the peaks in standard chromatograms. The width of the retention time 
window used to make identifications should be based upon measurements of 
actual retention time variations of standards over the course of a day. 
Three times the standard deviation of a retention time for a compound 
can be used to calculate a suggested window size; however, the 
experience of the analyst should weigh heavily in the interpretation of 
chromatograms.
    12.6  If the response for a peak exceeds the working range of the 
system, dilute the extract and reanalyze.
    12.7  If the measurement of the peak response is prevented by the 
presence of interferences, further cleanup is required.

                            13. Calculations

    13.1  Determine the concentration of individual compounds in the 
sample.
    13.1.1  If the external standard calibration procedure is used, 
calculate the amount of material injected from the peak response using 
the calibration curve or calibration factor determined in Section 7.2.2. 
The concentration in the sample can be calculated from Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.108

                                                              Equation 2

where:
A=Amount of material injected (ng).
Vi=Volume of extract injected ([mu]L).
Vt=Volume of total extract ([mu]L).
Vs=Volume of water extracted (mL).

    13.1.2  If the internal standard calibration procedure is used, 
calculate the concentration in the sample using the response factor (RF) 
determined in Section 7.3.2 and Equation 3.
[GRAPHIC] [TIFF OMITTED] TC15NO91.109

                                                              Equation 3

where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Is=Amount of internal standard added to each extract ([mu]g).
Vo=Volume of water extracted (L).

    13.2  When it is apparent that two or more PCB (Aroclor) mixtures 
are present, the Webb and McCall procedure \16\ may be used to identify 
and quantify the Aroclors.
    13.3  For multicomponent mixtures (chlordane, toxaphene, and PCBs) 
match retention times of peaks in the standards with peaks in the 
sample. Quantitate every identifiable peak unless interference with 
individual peaks persist after cleanup. Add peak height or peak area of 
each identified peak in the chromatogram. Calculate as total response in 
the sample versus total response in the standard.
    13.4  Report results in [mu]g/L without correction for recovery 
data. All QC data obtained should be reported with the sample results.

                         14. Method Performance

    14.1  The method detection limit (MDL) is defined as the minimum 
concentration of a substance that can be measured and reported with 99% 
confidence that the value is above zero.\1\ The MDL concentrations 
listed in Table 1 were obtained using reagent water.\17\ Similar results 
were achieved using representative wastewaters. The MDL actually 
achieved in a given analysis will vary depending on instrument 
sensitivity and matrix effects.
    14.2  This method has been tested for linearity of spike recovery 
from reagent water and has been demonstrated to be applicable over the 
concentration range from 4xMDL to 1000xMDL with the following 
exceptions: Chlordane recovery at 4xMDL was low (60%);

[[Page 120]]

Toxaphene recovery was demonstrated linear over the range of 10xMDL to 
1000xMDL.\17\
    14.3  This method was tested by 20 laboratories using reagent water, 
drinking water, surface water, and three industrial wastewaters spiked 
at six concentrations.\18\ Concentrations used in the study ranged from 
0.5 to 30 [mu]g/L for single-component pesticides and from 8.5 to 400 
[mu]g/L for multicomponent parameters. Single operator precision, 
overall precision, and method accuracy were found to be directly related 
to the concentration of the parameter and essentially independent of the 
sample matrix. Linear equations to describe these relationships are 
presented in Table 4.

                               References

    1. 40 CFR part 136, appendix B.
    2. ``Determination of Pesticides and PCBs in Industrial and 
Municipal Wastewaters,'' EPA 600/4-82-023, National Technical 
Information Service, PB82-214222, Springfield, Virginia 22161, April 
1982.
    3. ASTM Annual Book of Standards, Part 31, D3694-78. ``Standard 
Practices for Preparation of Sample Containers and for Preservation of 
Organic Constituents,'' American Society for Testing and Materials, 
Philadelphia.
    4. Giam, C.S., Chan, H.S., and Nef, G.S., ``Sensitive Method for 
Determination of Phthalate Ester Plasticizers in Open-Ocean Biota 
Samples,'' Analytical Chemistry, 47, 2225 (1975).
    5. Giam, C.S., Chan, H.S. ``Control of Blanks in the Analysis of 
Phthalates in Air and Ocean Biota Samples,'' U.S. National Bureau of 
Standards, Special Publication 442, pp. 701-708, 1976.
    6. ``Carcinogens--Working With Carcinogens,'' Department of Health, 
Education, and Welfare, Public Health Service, Center for Disease 
Control, National Institute for Occupational Safety and Health, 
Publication No. 77-206, August 1977.
    7. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR 
part 1910), Occupational Safety and Health Administration, OSHA 2206 
(Revised, January 1976).
    8. ``Safety in Academic Chemistry Laboratories,'' American Chemical 
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
    9. Mills, P.A. ``Variation of Florisil Activity: Simple Method for 
Measuring Absorbent Capacity and Its Use in Standardizing Florisil 
Columns,'' Journal of the Association of Official Analytical Chemists, 
51, 29, (1968).
    10. Provost, L.P., and Elder, R.S. ``Interpretation of Percent 
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44 
used in the equation in Section 8.3.3 is two times the value 1.22 
derived in this report.)
    11. ASTM Annual Book of Standards, Part 31, D3370-76. ``Standard 
Practices for Sampling Water,'' American Society for Testing and 
Materials, Philadelphia.
    12. ``Methods 330.4 (Titrimetric, DPD-FAS) and 330.5 
(Spectrophotometric, DPD) for Chlorine, Total Residual,'' Methods for 
Chemical Analysis of Water and Wastes, EPA-600/4-79-020, U.S. 
Environmental Protection Agency, Environmental Monitoring and Support 
Laboratory, Cincinnati, Ohio 45268, March 1979.
    13. Goerlitz, D.F., and Law, L.M. Bulletin for Environmental 
Contamination and Toxicology, 6, 9 (1971).
    14. ``Manual of Analytical Methods for the Analysis of Pesticides in 
Human and Environmental Samples,'' EPA-600/8-80-038, U.S. Environmental 
Protection Agency, Health Effects Research Laboratory, Research Triangle 
Park, North Carolina.
    15. Burke, J.A. ``Gas Chromatography for Pesticide Residue Analysis; 
Some Practical Aspects,'' Journal of the Association of Official 
Analytical Chemists, 48, 1037 (1965).
    16. Webb, R.G., and McCall, A.C. ``Quantitative PCB Standards for 
Election Capture Gas Chromatography,'' Journal of Chromatographic 
Science, 11, 366 (1973).
    17. ``Method Detection Limit and Analytical Curve Studies, EPA 
Methods 606, 607, and 608,'' Special letter report for EPA Contract 68-
03-2606, U.S. Environmental Protection Agency, Environmental Monitoring 
and Support Laboratory, Cincinnati, Ohio 45268, June 1980.
    18. ``EPA Method Study 18 Method 608--Organochlorine Pesticides and 
PCBs,'' EPA 600/4-84-061, National Technical Information Service, PB84-
211358, Springfield, Virginia 22161, June 1984.

     Table 1--Chromatographic Conditions and Method Detection Limits
------------------------------------------------------------------------
                                   Retention time (min)        Method
                                --------------------------   detection
           Parameter                                       limit  ([mu]g/
                                    Col. 1       Col. 2          L)
------------------------------------------------------------------------
[alpha]-BHC....................         1.35         1.82          0.003
[gamma]-BHC....................         1.70         2.13          0.004
[beta]-BHC.....................         1.90         1.97          0.006
Heptachlor.....................         2.00         3.35          0.003
[delta]-BHC....................         2.15         2.20          0.009
Aldrin.........................         2.40         4.10          0.004
Heptachlor epoxide.............         3.50         5.00          0.083
Endosulfan I...................         4.50         6.20          0.014

[[Page 121]]

 
4,4'-DDE.......................         5.13         7.15          0.004
Dieldrin.......................         5.45         7.23          0.002
Endrin.........................         6.55         8.10          0.006
4,4'-DDD.......................         7.83         9.08          0.011
Endosulfan II..................         8.00         8.28          0.004
4,4'-DDT.......................         9.40        11.75          0.012
Endrin aldehyde................        11.82         9.30          0.023
Endosulfan sulfate.............        14.22        10.70          0.066
Chlordane......................        mr           mr             0.014
Toxaphene......................        mr           mr             0.24
PCB-1016.......................        mr           mr            nd
PCB-1221.......................        mr           mr            nd
PCB-1232.......................        mt           mr            nd
PCB-1242.......................        mr           mr             0.065
PCB-1248.......................        mr           mr            nd
PCB-1254.......................        mr           mr            nd
PCB-1260.......................        mr           mr            nd
------------------------------------------------------------------------
 AColumn 1 conditions: Supelcoport (100/120 mesh) coated with 1.5% SP-
  2250/1.95% SP-2401 packed in a 1.8 m long x 4 mm ID glass column with
  5% methane/95% argon carrier gas at 60 mL/min flow rate. Column
  temperature held isothermal at 200  deg.C, except for PCB-1016 through
  PCB-1248, should be measured at 160  deg.C.
 AColumn 2 conditions: Supelcoport (100/120 mesh) coated with 3% OV-1
  packed in a 1.8 m long x 4 mm ID glass column with 5% methane/95%
  argon carrier gas at 60 mL/min flow rate. Column temperature held
  isothermal at 200  deg.C for the pesticides; at 140  deg.C for PCB-
  1221 and 1232; and at 170  deg.C for PCB-1016 and 1242 to 1268.
 Amr=Multiple peak response. See Figures 2 thru 10.
 And=Not determined.


 Table 2--Distribution of Chlorinated Pesticides and PCBs into Florisil
                           Column Fractions 2
------------------------------------------------------------------------
                                      Percent recovery by fraction \a\
            Parameter             --------------------------------------
                                        1            2            3
------------------------------------------------------------------------
Aldrin...........................          100  ...........  ...........
[alpha]-BHC......................          100  ...........  ...........
[beta]-BHC.......................           97  ...........  ...........
[delta]-BHC......................           98  ...........  ...........
[gamma]-BHC......................          100  ...........  ...........
Chlordane........................          100  ...........  ...........
4,4'-DDD.........................           99  ...........  ...........
4,4'-DDE.........................           98  ...........  ...........
4,4'-DDT.........................          100  ...........  ...........
Dieldrin.........................            0          100  ...........
Endosulfan I.....................           37           64  ...........
Endosulfan II....................            0            7           91
Endosulfan sulfate...............            0            0          106
Endrin...........................            4           96  ...........
Endrin aldehyde..................            0           68           26
Heptachlor.......................          100  ...........  ...........
Heptachlor epoxide...............          100  ...........  ...........
Toxaphene........................           96  ...........  ...........
PCB-1016.........................           97  ...........  ...........
PCB-1221.........................           97  ...........  ...........
PCB-1232.........................           95            4  ...........
PCB-1242.........................           97  ...........  ...........
PCB-1248.........................          103  ...........  ...........
PCB-1254.........................           90  ...........  ...........
PCB-1260.........................           95  ...........  ...........
------------------------------------------------------------------------
\a\ Eluant composition:
    Fraction 1-6% ethyl ether in hexane.
    Fraction 2-15% ethyl ether in hexane.
    Fraction 3-50% ethyl ether in hexane.


                                   Table 3--QC Acceptance Criteria--Method 608
----------------------------------------------------------------------------------------------------------------
                                                                                          Range for
                          Parameter                            Test conc.   Limit for s   X ([mu]g/   Range for
                                                               ([mu]g/L)     ([mu]g/L)       L)        P, Ps(%)
----------------------------------------------------------------------------------------------------------------
Aldrin......................................................          2.0          0.42   1.08-2.24       42-122
[alpha]-BHC.................................................          2.0          0.48   0.98-2.44       37-134

[[Page 122]]

 
[beta]-BHC..................................................          2.0          0.64   0.78-2.60       17-147
[delta]-BHC.................................................          2.0          0.72   1.01-2.37       19-140
[gamma]-BHC.................................................          2.0          0.46   0.86-2.32       32-127
Chlordane...................................................         50           10.0    27.6-54.3       45-119
4,4 '-DDD...................................................         10            2.8     4.8-12.6       31-141
4,4 '-DDE...................................................          2.0          0.55   1.08-2.60       30-145
4,4'-DDT....................................................         10            3.6     4.6-13.7       25-160
Dieldrin....................................................          2.0          0.76   1.15-2.49       36-146
Endosulfan I................................................          2.0          0.49   1.14-2.82       45-153
Endosulfan II...............................................         10            6.1     2.2-17.1        D-202
Endosulfan Sulfate..........................................         10            2.7     3.8-13.2       26-144
Endrin......................................................         10            3.7     5.1-12.6       30-147
Heptachlor..................................................          2.0          0.40   0.86-2.00       34-111
Heptachlor epoxide..........................................          2.0          0.41   1.13-2.63       37-142
Toxaphene...................................................         50.0         12.7    27.8-55.6       41-126
PCB-1016....................................................         50           10.0    30.5-51.5       50-114
PCB-1221....................................................         50           24.4    22.1-75.2       15-178
PCB-1232....................................................         50           17.9    14.0-98.5       10-215
PCB-1242....................................................         50           12.2    24.8-69.6       39-150
PCB-1248....................................................         50           15.9    29.0-70.2       38-158
PCB-1254....................................................         50           13.8    22.2-57.9       29-131
PCB-1260....................................................         50           10.4    18.7-54.9        8-127
----------------------------------------------------------------------------------------------------------------
s=Standard deviation of four recovery measurements, in [mu]g/L (Section 8.2.4).
X=Average recovery for four recovery measurements, in [mu]g/L (Section 8.2.4).
P, Ps=Percent recovery measured (Section 8.3.2, Section 8.4.2).
D=Detected; result must be greater than zero.
 
Note: These criteria are based directly upon the method performance data in Table 4. Where necessary, the limits
  for recovery have been broadened to assure applicability of the limits to concentrations below those used to
  develop Table 4.


                Table 4--Method Accuracy and Precision as Functions of Concentration--Method 608
----------------------------------------------------------------------------------------------------------------
                                                         Accuracy, as       Single analyst
                      Parameter                          recovery, X'       precision, sr'    Overall precision,
                                                           ([mu]g/L)           ([mu]g/L)         S' ([mu]g/L)
----------------------------------------------------------------------------------------------------------------
Aldrin..............................................          0.81C+0.04          0.16X-0.04          0.20X-0.01
[alpha]-BHC.........................................          0.84C+0.03          0.13X+0.04          0.23X-0.00
[beta]-BHC..........................................          0.81C+0.07          0.22X-0.02          0.33X-0.05
[delta]-BHC.........................................          0.81C+0.07          0.18X+0.09          0.25X+0.03
[gamma]-BHC.........................................          0.82C-0.05          0.12X+0.06          0.22X+0.04
Chlordane...........................................          0.82C-0.04          0.13X+0.13          0.18X+0.18
4,4'-DDD............................................          0.84C+0.30          0.20X-0.18          0.27X-0.14
4,4'-DDE............................................          0.85C+0.14          0.13X+0.06          0.28X-0.09
4,4'-DDT............................................          0.93C-0.13          0.17X+0.39          0.31X-0.21
Dieldrin............................................          0.90C+0.02          0.12X+0.19          0.16X+0.16
Endosulfan I........................................          0.97C+0.04          0.10X+0.07          0.18X+0.08
Endosulfan II.......................................          0.93C+0.34         0.41X--0.65          0.47X-0.20
Endosulfan Sulfate..................................          0.89C-0.37          0.13X+0.33          0.24X+0.35
Endrin..............................................          0.89C-0.04          0.20X+0.25          0.24X+0.25
Heptachlor..........................................          0.69C+0.04          0.06X+0.13          0.16X+0.08
Heptachlor epoxide..................................          0.89C+0.10          0.18X-0.11          0.25X-0.08
Toxaphene...........................................          0.80C+1.74          0.09X+3.20          0.20X+0.22
PCB-1016............................................          0.81C+0.50          0.13X+0.15          0.15X+0.45
PCB-1221............................................          0.96C+0.65          0.29X-0.76          0.35X-0.62
PCB-1232............................................         0.91C+10.79          0.21X-1.93          0.31X+3.50
PCB-1242............................................          0.93C+0.70          0.11X+1.40          0.21X+1.52
PCB-1248............................................          0.97C+1.06          0.17X+0.41          0.25X-0.37
PCB-1254............................................          0.76C+2.07          0.15X+1.66          0.17X+3.62
PCB-1260............................................          0.66C+3.76          0.22X-2.37          0.39X-4.86
----------------------------------------------------------------------------------------------------------------
X'=Expected recovery for one or more measurements of a sample containing a concentration of C, in [mu]g/L.
sr'=Expected single analyst standard deviation of measurements at an average concentration found of X, in [mu]g/
  L.
S'=Expected interlaboratory standard deviation of measurements at an average concentration found of X, in [mu]g/
  L.
C=True value for the concentration, in [mu]g/L.
X=Average recovery found for measurements of samples containing a concentration of C, in [mu]g/L.


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[GRAPHIC] [TIFF OMITTED] TC02JY92.028

                Method 609--Nitroaromatics and Isophorone

                        1. Scope and Application

    1.1  This method covers the determination of certain nitroaromatics 
and isophorone. The following parameters may be determined by this 
method:

------------------------------------------------------------------------
                   Parameter                     STORET No.    CAS No.
------------------------------------------------------------------------
2,4-Dinitrotoluene............................        34611     121-14-2
2,6-Dinitrotoluene............................        34626     606-20-2
Isophorone....................................        34408      78-59-1
Nitrobenzene..................................        34447      98-95-3
------------------------------------------------------------------------

    1.2  This is a gas chromatographic (GC) method applicable to the 
determination of

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the compounds listed above in municipal and industrial discharges as 
provided under 40 CFR 136.1. When this method is used to analyze 
unfamiliar samples for any or all of the compounds above, compound 
identifications should be supported by at least one additional 
qualitative technique. This method describes analytical conditions for a 
second gas chromatographic column that can be used to confirm 
measurements made with the primary column. Method 625 provides gas 
chromatograph/mass spectrometer (GC/MS) conditions appropriate for the 
qualitative and quantitative confirmation of results for all of the 
parameters listed above, using the extract produced by this method.
    1.3  The method detection limit (MDL, defined in Section 14.1)\1\ 
for each parameter is listed in Table 1. The MDL for a specific 
wastewater may differ from those listed, depending upon the nature of 
interferences in the sample matrix.
    1.4  The sample extraction and concentration steps in this method 
are essentially the same as in Methods 606, 608, 611, and 612. Thus, a 
single sample may be extracted to measure the parameters included in the 
scope of each of these methods. When cleanup is required, the 
concentration levels must be high enough to permit selecting aliquots, 
as necessary, to apply appropriate cleanup procedures. The analyst is 
allowed the latitude, under Section 12, to select chromatographic 
conditions appropriate for the simultaneous measurement of combinations 
of these parameters.
    1.5  Any modification of this method, beyond those expressly 
permitted, shall be considered as a major modification subject to 
application and approval of alternate test procedures under 40 CFR 136.4 
and 136.5.
    1.6  This method is restricted to use by or under the supervision of 
analysts experienced in the use of a gas chromatograph and in the 
interpretation of gas chromatograms. Each analyst must demonstrate the 
ability to generate acceptable results with this method using the 
procedure described in Section 8.2.

                          2. Summary of Method

    2.1  A measured volume of sample, approximately 1-L, is extracted 
with methylene chloride using a separatory funnel. The methylene 
chloride extract is dried and exchanged to hexane during concentration 
to a volume of 10 mL or less. Isophorone and nitrobenzene are measured 
by flame ionization detector gas chromatography (FIDGC). The 
dinitrotoluenes are measured by electron capture detector gas 
chromatography (ECDGC).\2\
    2.2  The method provides a Florisil column cleanup procedure to aid 
in the elimination of interferences that may be encountered.

                            3. Interferences

    3.1  Method interferences may be caused by contaminants in solvents, 
reagents, glassware, and other sample processing hardware that lead to 
discrete artifacts and/or elevated baseliles in gas chromatograms. All 
of these materials must be routinely demonstrated to be free from 
interferences under the conditions of the analysis by running laboratory 
reagent blanks as described in Section 8.1.3.
    3.1.1  Glassware must be scrupulously cleaned.\3\ Clean all 
glassware as soon as possible after use by rinsing with the last solvent 
used in it. Solvent rinsing should be followed by detergent washing with 
hot water, and rinses with tap water and distilled water. The glassware 
should then be drained dry, and heated in a muffle furnace at 400  deg.C 
for 15 to 30 min. Some thermally stable materials, such as PCBs, may not 
be eliminated by this treatment. Solvent rinses with acetone and 
pesticide quality hexane may be substituted for the muffle furnace 
heating. Thorough rinsing with such solvents usually eliminates PCB 
interference. Volumetric ware should not be heated in a muffle furnace. 
After drying and cooling, glassware should be sealed and stored in a 
clean environment to prevent any accumulation of dust or other 
contaminants. Store inverted or capped with aluminum foil.
    3.1.2  The use of high purity reagents and solvents helps to 
minimize interference problems. Purification of solvents by distillation 
in all-glass systems may be required.
    3.2  Matrix interferences may be caused by contaminants that are co-
extracted from the sample. The extent of matrix interferences will vary 
considerably from source to source, depending upon the nature and 
diversity of the industrial complex or municipality being sampled. The 
cleanup procedure in Section 11 can be used to overcome many of these 
interferences, but unique samples may require additional cleanup 
approaches to achieve the MDL listed in Table 1.

                                4. Safety

    4.1  The toxicity or carcinogenicity of each reagent used in this 
method has not been precisely defined; however, each chemical compound 
should be treated as a potential health hazard. From this viewpoint, 
exposure to these chemicals must be reduced to the lowest possible level 
by whatever means available. The laboratory is responsible for 
maintaining a current awareness file of OSHA regulations regarding the 
safe handling of the chemicals specified in this method. A reference 
file of material data handling sheets should also be made available to 
all personnel involved in the chemical analysis. Additional references 
to laboratory safety are available and have been identified 
\4\[hyphen]\6\ for the information of the analyst.

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                       5. Apparatus and Materials

    5.1  Sampling equipment, for discrete or composite sampling.
    5.1.1  Grab sample bottle--1-L or 1-qt, amber glass, fitted with a 
screw cap lined with Teflon. Foil may be substituted for Teflon if the 
sample is not corrosive. If amber bottles are not available, protect 
samples from light. The bottle and cap liner must be washed, rinsed with 
acetone or methylene chloride, and dried before use to minimize 
contamination.
    5.1.2  Automatic sampler (optional)--The sampler must incorporate 
glass sample containers for the collection of a minimum of 250 mL of 
sample. Sample containers must be kept refrigerated at 4  deg.C and 
protected from light during compositing. If the sampler uses a 
peristaltic pump, a minimum length of compressible silicone rubber 
tubing may be used. Before use, however, the compressible tubing should 
be thoroughly rinsed with methanol, followed by repeated rinsings with 
distilled water to minimize the potential for contamination of the 
sample. An integrating flow meter is required to collect flow 
proportional composites.
    5.2  Glassware (All specifications are suggested. Catalog numbers 
are included for illustration only.):
    5.2.1  Separatory funnel--2-L, with Teflon stopcock.
    5.2.2  Drying column--Chromatographic column, approximately 400 mm 
long x 19 mm ID, with coarse frit filter disc.
    5.2.3  Chromatographic column--100 mm long x 10 mm ID, with Teflon 
stopcock.
    5.2.4  Concentrator tube, Kuderna-Danish--10-mL, graduated (Kontes 
K-570050-1025 or equivalent). Calibration must be checked at the volumes 
employed in the test. Ground glass stopper is used to prevent 
evaporation of extracts.
    5.2.5  Evaporative flask, Kuderna-Danish--500-mL (Kontes K-570001-
0500 or equivalent). Attach to concentrator tube with springs.
    5.2.6  Snyder column, Kuderna-Danish--Three-ball macro (Kontes K-
503000-0121 or equivalent).
    5.2.7  Snyder column, Kuderna-Danish--Two-ball micro (Kontes K-
569001-0219 or equivalent).
    5.2.8  Vials--10 to 15-mL, amber glass, with Teflon-lined screw cap.
    5.3  Boiling chips--Approximately 10/40 mesh. Heat to 400  deg.C for 
30 min or Soxhlet extract with methylene chloride.
    5.4  Water bath--Heated, with concentric ring cover, capable of 
temperature control (2  deg.C). The bath should be used in a 
hood.
    5.5  Balance--Analytical, capable of accurately weighing 0.0001 g.
    5.6  Gas chromatograph--An analytical system complete with gas 
chromatograph suitable for on-column injection and all required 
accessories including syringes, analytical columns, gases, detector, and 
strip-chart recorder. A data system is recommended for measuring peak 
areas.
    5.6.1  Column 1--1.2 m long x 2 or 4 mm ID glass, packed with 1.95% 
QF-1/1.5% OV-17 on Gas-Chrom Q (80/100 mesh) or equivalent. This column 
was used to develop the method performance statements given in Section 
14. Guidelines for the use of alternate column packings are provided in 
Section 12.1.
    5.6.2  Column 2--3.0 m long x 2 or 4 mm ID glass, packed with 3% OV-
101 on Gas-Chrom Q (80/100 mesh) or equivalent.
    5.6.3  Detectors--Flame ionization and electron capture detectors. 
The flame ionization detector (FID) is used when determining isophorone 
and nitrobenzene. The electron capture detector (ECD) is used when 
determining the dinitrotoluenes. Both detectors have proven effective in 
the analysis of wastewaters and were used in develop the method 
performance statements in Section 14. Guidelines for the use to 
alternate detectors are provided in Section 12.1.

                               6. Reagents

    6.1  Reagent water--Reagent water is defined as a water in which an 
interferent is not observed at the MDL of the parameters of interest.
    6.2  Sodium hydroxide solution (10 N)--Dissolve 40 g of NaOH (ACS) 
in reagent water and dilute to 100 mL.
    6.3  Sulfuric acid (1+1)--Slowly, add 50 mL of 
H2SO4 (ACS, sp. gr. 1.84) to 50 mL of reagent 
water.
    6.4  Acetone, hexane, methanol, methylene chloride--Pesticide 
quality or equivalent.
    6.5  Sodium sulfate--(ACS) Granular, anhydrous. Purify by heating at 
400  deg.C for 4 h in a shallow tray.
    6.6  Florisil--PR grade (60/100 mesh). Purchase activated at 1250 
deg.F and store in dark in glass containers with ground glass stoppers 
or foil-lined screw caps. Before use, activate each batch at least 16 h 
at 200  deg.C in a foil-covered glass container and allow to cool.
    6.7  Stock standard solutions (1.00 [mu]g/[mu]L)--Stock standard 
solutions can be prepared from pure standard materials or purchased as 
certified solutions.
    6.7.1  Prepare stock standard solutions by accurately weighing about 
0.0100 g of pure material. Dissolve the material in hexane and dilute to 
volume in a 10-mL volumetric flask. Larger volumes can be used at the 
convenience of the analyst. When compound purity is assayed to be 96% or 
greater, the weight can be used without correction to calculate the 
concentration of the stock standard. Commercially prepared stock 
standards can be used at any concentration if they are certified by the 
manufacturer or by an independent source.
    6.7.2  Transfer the stock standard solutions into Teflon-sealed 
screw-cap bottles.

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Store at 4  deg.C and protect from light. Stock standard solutions 
should be checked frequently for signs of degradation or evaporation, 
especially just prior to preparing calibration standards from them.
    6.7.3  Stock standard solutions must be replaced after six months, 
or sooner if comparison with check standards indicates a problem.
    6.8  Quality control check sample concentrate--See Section 8.2.1.

                             7. Calibration

    7.1  Establish gas chromatographic operating conditions equivalent 
to those given in Table 1. The gas chromatographic system can be 
calibrated using the external standard technique (Section 7.2) or the 
internal standard technique (Section 7.3).
    7.2  External standard calibration procedure:
    7.2.1  Prepare calibration standards at a minimum of three 
concentration levels for each parameter of interest by adding volumes of 
one or more stock standards to a volumetric flask and diluting to volume 
with hexane. One of the external standards should be at a concentration 
near, but above, the MDL (Table 1) and the other concentrations should 
correspond to the expected range of concentrations found in real samples 
or should define the working range of the detector.
    7.2.2  Using injections of 2 to 5 [mu]L, analyze each calibration 
standard according to Section 12 and tabulate peak height or area 
responses against the mass injected. The results can be used to prepare 
a calibration curve for each compound. Alternatively, if the ratio of 
response to amount injected (calibration factor) is a constant over the 
working range (<10% relative standard deviation, RSD) linearity through 
the origin can be assumed and the average ratio or calibration factor 
can be used in place of a calibration curve.
    7.3  Internal standard calibration procedure--To use this approach, 
the analyst must select one or more internal standards that are similar 
in analytical behavior to the compounds of interest. The analyst must 
further demonstrate that the measurement of the internal standard is not 
affected by method or matrix interferences. Because of these 
limitations, no internal standard can be suggested that is applicable to 
all samples.
    7.3.1  Prepare calibration standards at a minimum of three 
concentration levels for each parameter of interest by adding volumes of 
one or more stock standards to a volumetric flash. To each calibration 
standard, add a known constant amount of one or more internal standards, 
and dilute to volume with hexane. One of the standards should be at a 
concentration near, but above, the MDL and the other concentrations 
should correspond to the expected range of concentrations found in real 
samples or should define the working range of the detector.
    7.3.2  Using injections of 2 to 5 [mu]L, analyze each calibration 
standard according to Section 12 and tabulate peak height or area 
responses against concentration for each compound and internal standard. 
Calculate response factors (RF) for each compound using Equation 1.
    Equation 1.
    [GRAPHIC] [TIFF OMITTED] TC15NO91.110
    
where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Cis=Concentration of the internal standard ([mu]g/L).
Cs=Concentration of the parameter to be measured ([mu]g/L).

    If the RF value over the working range is a constant (<10% RSD), the 
RF can be assumed to be invariant and the average RF can be used for 
calculations. Alternatively, the results can be used to plot a 
calibration curve of response ratios, As/Ais, vs. 
RF.
    7.4  The working calibration curve, calibration factor, or RF must 
be verified on each working day by the measurement of one or more 
calibration standards. If the response for any parameter varies from the 
predicted response by more than 15%, a new calibration curve 
must be prepared for that compound.
    7.5  Before using any cleanup procedure, the analyst must process a 
series of calibration standards through the procedure to validate 
elution patterns and the absence of interferences from the reagents.

                           8. Quality Control

    8.1  Each laboratory that uses this method is required to operate a 
formal quality control program. The minimum requirements of this program 
consist of an initial demonstration of laboratory capability and an 
ongoing analysis of spiked samples to evaluate and document data 
quality. The laboratory must maintain records to document the quality of 
data that is generated. Ongoing data quality checks are compared with 
established performance criteria to determine if the results of analyses 
meet the performance characteristics of the method. When results of 
sample spikes indicate atypical method performance, a quality control 
check standard must be analyzed to confirm that the measurements were 
performed in an in-control mode of operation.
    8.1.1  The analyst must make an initial, one-time, demonstration of 
the ability to

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generate acceptable accuracy and precision with this method. This 
ability is established as described in Section 8.2.
    8.1.2  In recognition of advances that are occurring in 
chromatography, the analyst is permitted certain options (detailed in 
Sections 10.4, 11.1, and 12.1) to improve the separations or lower the 
cost of measurements. Each time such a modification is made to the 
method, the analyst is required to repeat the procedure in Section 8.2.
    8.1.3  Before processing any samples, the analyst must analyze a 
reagent water blank to demonstrate that interferences from the 
analytical system and glassware are under control. Each time a set of 
samples is extracted or reagents are changed, a reagent water blank must 
be processed as a safeguard against laboratory contamination.
    8.1.4  The laboratory must, on an ongoing basis, spike and analyze a 
minimum of 10% of all samples to monitor and evaluate laboratory data 
quality. This procedure is described in Section 8.3.
    8.1,5  The laboratory must, on an ongoing basis, demonstrate through 
the analyses of quality control check standards that the operation of 
the measurement system is in control. This procedure is described in 
Section 8.4. The frequency of the check standard analyses is equivalent 
to 10% of all samples analyzed but may be reduced if spike recoveries 
from samples (Section 8.3) meet all specified quality control criteria.
    8.1.6  The laboratory must maintain performance records to document 
the quality of data that is generated. This procedure is described in 
Section 8.5.
    8.2  To establish the ability to generate acceptable accuracy and 
precision, the analyst must perform the following operations.
    8.2.1  A quality control (QC) check sample concentrate is required 
containing each parameter of interest in acetone at a concentration of 
20 [mu]g/mL for each dinitrotoluene and 100 [mu]g/mL for isophorone and 
nitrobenzene. The QC check sample concentrate must be obtained from the 
U.S. Environmental Protection Agency, Environmental Monitoring and 
Support Laboratory in Cincinnati, Ohio, if available. If not available 
from that source, the QC check sample concentrate must be obtained from 
another external source. If not available from either source above, the 
QC check sample concentrate must be prepared by the laboratory using 
stock standards prepared independently from those used for calibration.
    8.2.2  Using a pipet, prepare QC check samples at the test 
concentrations shown in Table 2 by adding 1.00 mL of QC check sample 
concentrate to each of four 1-L aliquots of reagent water.
    8.2.3  Analyze the well-mixed QC check samples according to the 
method beginning in Section 10.
    8.2.4  Calculate the average recovery (X) in [mu]g/L, and the 
standard deviation of the recovery (s) in [mu]g/L, for each parameter 
using the four results.
    8.2.5  For each parameter compare s and X with the corresponding 
acceptance criteria for precision and accuracy, respectively, found in 
Table 2. If s and X for all parameters of interest meet the acceptance 
criteria, the system performance is acceptable and analysis of actual 
samples can begin. If any individual s exceeds the precision limit or 
any individual X falls outside the range for accuracy, the system 
performance is unacceptable for that parameter. Locate and correct the 
source of the problem and repeat the test for all parameters of interest 
beginning with Section 8.2.2.
    8.3  The laboratory must, on an ongoing basis, spike at least 10% of 
the samples from each sample site being monitored to assess accuracy. 
For laboratories analyzing one to ten samples per month, at least one 
spiked sample per month is required.
    8.3.1  The concentration of the spike in the sample should be 
determined as follows:
    8.3.1.1  If, as in compliance monitoring, the concentration of a 
specific parameter in the sample is being checked against a regulatory 
concentration limit, the spike should be at that limit or 1 to 5 times 
higher than the background concentration determined in Section 8.3.2, 
whichever concentration would be larger.
    8.3.1.2  If the concentration of a specific parameter in the sample 
is not being checked against a limit specific to that parameter, the 
spike should be at the test concentration in Section 8.2.2 or 1 to 5 
times higher than the background concentration determined in Section 
8.3.2, whichever concentration would be larger.
    8.3.1.3  If it is impractical to determile background levels before 
spiking (e.g., maximum holding times will be exceeded), the spike 
concentration should be (1) the regulatory concentration limit, if any; 
or, if none (2) the larger of either 5 times higher than the expected 
background concentration or the test concentration in Section 8.2.2.
    8.3.2  Analyze one sample aliquot to determine the background 
concentration (B) of each parameter. If necessary, prepare a new QC 
check sample concentrate (Section 8.2.1) appropriate for the background 
concentrations in the sample. Spike a second sample aliquot with 1.0 mL 
of the QC check sample concentrate and analyze it to determine the 
concentration after spiking (A) of each parameter. Calculate each 
percent recovery (P) as 100 (A-B)%/T, where T is the known true value of 
the spike.
    8.3.3  Compare the percent recovery (P) for each parameter with the 
corresponding QC acceptance criteria found in Table 2. These acceptance 
criteria were calculated to include an allowance for error in 
measurement

[[Page 137]]

of both the background and spike concentrations, assuming a spike to 
background ratio of 5:1. This error will be accounted for to the extent 
that the analyst's spike to background ratio approaches 5:1.\7\ If 
spiking was performed at a concentration lower than the test 
concentration in Section 8.2.2, the analyst must use either the QC 
acceptance criteria in Table 2, or optional QC acceptance criteria 
calculated for the specific spike concentration. To calculate optional 
acceptance criteria for the recovery of a parameter: (1) Calculate 
accuracy (X') using the equation in Table 3, substituting the spike 
concentration (T) for C; (2) calculate overall precision (S') using the 
equation in Table 3, substituting X' for X8; (3) calculate the range for 
recovery at the spike concentration as (100 X'/T) 2.44 (100 
S'/T)%.\7\
    8.3.4  If any individual P falls outside the designated range for 
recovery, that parameter has failed the acceptance criteria. A check 
standard containing each parameter that failed the criteria must be 
analyzed as described in Section 8.4.
    8.4.  If any parameter fails the acceptance criteria for recovery in 
Section 8.3, a QC check standard containing each parameter that failed 
must be prepared and analyzed.
    Note: The frequency for the required analysis of a QC check standard 
will depend upon the number of parameters being simultaneously tested, 
the complexity of the sample matrix, and the performance of the 
laboratory.
    8.4.1  Prepare the QC check standard by adding 1.0 mL of QC check 
sample concentrate (Section 8.2.1 or 8.3.2) to 1 L of reagent water. The 
QC check standard needs only to contain the parameters that failed 
criteria in the test in Section 8.3.
    8.4.2  Analyze the QC check standard to determine the concentration 
measured (A) of each parameter. Calculate each percent recovery 
(Ps) as 100 (A/T)%, where T is the true value of the standard 
concentration.
    8.4.3  Compare the percent recovery (Ps) for each 
parameter with the corresponding QC acceptance criteria found in Table 
2. Only parameters that failed the test in Section 8.3 need to be 
compared with these criteria. If the recovery of any such parameter 
falls outside the designated range, the laboratory performance for that 
parameter is judged to be out of control, and the problem must be 
immediately identified and corrected. The analytical result for that 
parameter in the unspiked sample is suspect and may not be reported for 
regulatory compliance purposes.
    8.5  As part of QC program for the laboratory, method accuracy for 
wastewater samples must be assessed and records must be maintained. 
After the analysis of five spiked wastewater samples as in Section 8.3, 
calculate the average percent recovery (P) and the standard deviation of 
the percent recovery (sp). Express the accuracy assessment as 
a percent recovery interval from P-2sp to P+2sp. 
If P=90% and sp = 10%, for example, the accuracy interval is 
expressed as 70-110%. Update the accuracy assessment for each parameter 
on a regular basis (e.g. after each five to ten new accuracy 
measurements).
    8.6  It is recommended that the laboratory adopt additional quality 
assurance practices for use with this method. The specific practices 
that are most productive depend upon the needs of the laboratory and the 
nature of the samples. Field duplicates may be analyzed to assess the 
precision of the environmental measurements. When doubt exists over the 
identification of a peak on the chromatogram, confirmatory techniques 
such as gas chromatography with a dissimilar column, specific element 
detector, or mass spectrometer must be used. Whenever possible, the 
laboratory should analyze standard reference materials and participate 
in relevant performance evaluation studies.

            9. Sample Collection, Preservation, and Handling

    9.1  Grab samples must be collected in glass containers. 
Conventional sampling practices \8\ should be followed, except that the 
bottle must not be prerinsed with sample before collection. Composite 
samples should be collected in refrigerated glass containers in 
accordance with the requirements of the program. Automatic sampling 
equipment must be as free as possible of Tygon tubing and other 
potential sources of contamination.
    9.2  All samples must be iced or refrigerated at 4  deg.C from the 
time of collection until extraction.
    9.3  All samples must be extracted within 7 days of collection and 
completely analyzed within 40 days of extraction.\2\

                          10. Sample Extraction

    10.1  Mark the water meniscus on the side of the sample bottle for 
later determination of sample volume. Pour the entire sample into a 2-L 
separatory funnel. Check the pH of the sample with wide-range pH paper 
and adjust to within the range of 5 to 9 with sodium hydroxide solution 
or sulfuric acid.
    10.2  Add 60 mL of methylene chloride to the sample bottle, seal, 
and shake 30 s to rinse the inner surface. Transfer the solvent to the 
separatory funnel and extract the sample by shaking the funnel for 2 
min. with periodic venting to release excess pressure. Allow the organic 
layer to separate from the water phase for a minimum of 10 min. If the 
emulsion interface between layers is more than one-third the volume of 
the solvent layer, the analyst must employ mechanical techniques to 
complete the phase separation. The optimum technique depends upon the 
sample, but may include stirring, filtration

[[Page 138]]

of the emulsion through glass wool, centrifugation, or other physical 
methods. Collect the methylene chloride extract in a 250-mL Erlenmeyer 
flask.
    10.3  Add a second 60-mL volume of methylene chloride to the sample 
bottle and repeat the extraction procedure a second time, combining the 
extracts in the Erlenmeyer flask. Perform a third extraction in the same 
manner.
    10.4  Assemble a Kuderna-Danish (K-D) concentrator by attaching a 
10-mL concentrator tube to a 500-mL evaporative flask. Other 
concentration devices or techniques may be used in place of the K-D 
concentrator if the requirements of Section 8.2 are met.
    10.5  Pour the combined extract through a solvent-rinsed drying 
column containing about 10 cm of anhydrous sodium sulfate, and collect 
the extract in the K-D concentrator. Rinse the Erlenmeyer flask and 
column with 20 to 30 mL of methylene chloride to complete the 
quantitative transfer.
    10.6  Sections 10.7 and 10.8 describe a procedure for exchanging the 
methylene chloride solvent to hexane while concentrating the extract 
volume to 1.0 mL. When it is not necessary to achieve the MDL in Table 
2, the solvent exchange may be made by the addition of 50 mL of hexane 
and concentration to 10 mL as described in Method 606, Sections 10.7 and 
10.8.
    10.7  Add one or two clean boiling chips to the evaporative flask 
and attach a three-ball Snyder column. Prewet the Snyder column by 
adding about 1 mL of methylene chloride to the top. Place the K-D 
apparatus on a hot water bath (60 to 65  deg.C) so that the concentrator 
tube is partially immersed in the hot water, and the entire lower 
rounded surface of the flask is bathed with hot vapor. Adjust the 
vertical position of the apparatus and the water temperature as required 
to complete the concentration in 15 to 20 min. At the proper rate of 
distillation the balls of the column will actively chatter but the 
chambers will not flood with condensed solvent. When the apparent volume 
of liquid reaches 1 mL, remove the K-D apparatus and allow it to drain 
and cool for at least 10 min.
    10.8  Remove the Snyder column and rinse the flask and its lower 
joint into the concentrator tube with 1 to 2 mL of methylene chloride. A 
5-mL syringe is recommended for this operation. Add 1 to 2 mL of hexane 
and a clean boiling chip to the concentrator tube and attach a two-ball 
micro-Snyder column. Prewet the column by adding about 0.5 mL of hexane 
to the top. Place the micro-K-D apparatus on a hot water bath (60 to 65  
deg.C) so that the concentrator tube is partially immersed in the hot 
water. Adjust the vertical position of the apparatus and the water 
temperature as required to complete the concentration in 5 to 10 min. At 
the proper rate of distillation the balls of the column will actively 
chatter but the chambers will not flood. When the apparent volume of 
liquid reaches 0.5 mL, remove the K-D apparatus and allow it to drain 
and cool for at least 10 min.
    10.9  Remove the micro-Snyder column and rinse its lower joint into 
the concentrator tube with a minimum amount of hexane. Adjust the 
extract volume to 1.0 mL. Stopper the concentrator tube and store 
refrigerated if further processing will not be performed immediately. If 
the extract will be stored longer than two days, it should be 
transferred to a Teflon-sealed screw-cap vial. If the sample extract 
requires no further cleanup, proceed with gas chromatographic analysis 
(Section 12). If the sample requires further cleanup, proceed to Section 
11.
    10.10  Determine the original sample volume by refilling the sample 
bottle to the mark and transferring the liquid to a 1000-mL graduated 
cylinder. Record the sample volume to the nearest 5 mL.

                       11. Cleanup and Separation

    11.1  Cleanup procedures may not be necessary for a relatively clean 
sample matrix. If particular circumstances demand the use of a cleanup 
procedure, the analyst may use the procedure below or any other 
appropriate procedure. However, the analyst first must demonstrate that 
the requirements of Section 8.2 can be met using the method as revised 
to incorporate the cleanup procedure.
    11.2  Florisil column cleanup:
    11.2.1  Prepare a slurry of 10 g of activated Florisil in methylene 
chloride/hexane (1+9)(V/V) and place the Florisil into a chromatographic 
column. Tap the column to settle the Florisil and add 1 cm of anhydrous 
sodium sulfate to the top. Adjust the elution rate to about 2 mL/min.
    11.2.2  Just prior to exposure of the sodium sulfate layer to the 
air, quantitatively transfer the sample extract onto the column using an 
additional 2 mL of hexane to complete the transfer. Just prior to 
exposure of the sodium sulfate layer to the air, add 30 mL of methylene 
chloride/hexane (1 + 9)(V/V) and continue the elution of the column. 
Discard the eluate.
    11.2.3  Next, elute the column with 30 mL of acetone/methylene 
chloride (1 + 9)(V/V) into a 500-mL K-D flask equipped with a 10-mL 
concentrator tube. Concentrate the collected fraction as in Sections 
10.6, 10.7, 10.8, and 10.9 including the solvent exchange to 1 mL of 
hexane. This fraction should contain the nitroaromatics and isophorone. 
Analyze by gas chromatography (Section 12).

                         12. Gas Chromatography

    12.1  Isophorone and nitrobenzene are analyzed by injection of a 
portion of the extract into an FIDGC. The dinitrotoluenes are analyzed 
by a separate injection into an ECDGC.

[[Page 139]]

Table 1 summarizes the recommended operating conditions for the gas 
chromatograph. Included in this table are retention times and MDL that 
can be achieved under these conditions. Examples of the separations 
achieved by Column 1 are shown in Figures 1 and 2. Other packed or 
capillary (open-tubular) columns, chromatographic conditions, or 
detectors may be used if the requirements of Section 8.2 are met.
    12.2  Calibrate the system daily as described in Section 7.
    12.3  If the internal standard calibration procedure is being used, 
the internal standard must be added to the same extract and mixed 
thoroughly immediately before injection into the gas chromatograph.
    12.4  Inject 2 to 5 [mu]L of the sample extract or standard into the 
gas chromatograph using the solvent-flush technique.\9\ Smaller (1.0 
[mu]L) volumes may be injected if automatic devices are employed. Record 
the volume injected to the nearest 0.05 [mu]L, the total extract volume, 
and the resulting peak size in area or peak height units.
    12.5  Identify the parameters in the sample by comparing the 
retention times of the peaks in the sample chromatogram with those of 
the peaks in standard chromatograms. The width of the retention time 
window used to make identifications should be based upon measurements of 
actual retention time variations of standards over the course of a day. 
Three times the standard deviation of a retention time for a compound 
can be used to calculate a suggested window size; however, the 
experience of the analyst should weigh heavily in the interpretation of 
chromatograms.
    12.6  If the response for a peak exceeds the working range of the 
system, dilute the extract and reanalyze.
    12.7  If the measurement of the peak response is prevented by the 
presence of interferences, further cleanup is required.

                            13. Calculations

    13.1  Determine the concentration of individual compounds in the 
sample.
    13.1.1  If the external standard calibration procedure is used, 
calculate the amount of material injected from the peak response using 
the calibration curve or calibration factor determined in Section 7.2.2. 
The concentration in the sample can be calculated from Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.111

                                                              Equation 2

where:
A=Amount of material injected (ng).
Vi=Volume of extract injected ([mu]L).
Vt=Volume of total extract ([mu]L).
Vs=Volume of water extracted (mL).

    13.1.2  If the internal standard calibration procedure is used, 
calculate the concentration in the sample using the response factor (RF) 
determined in Section 7.3.2 and Equation 3.
[GRAPHIC] [TIFF OMITTED] TC15NO91.112

                                                              Equation 3

where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Is=Amount of internal standard added to each extract ([mu]g).
Vo=Volume of water extracted (L).

    13.2  Report results in [mu]g/L without correction for recovery 
data. All QC data obtained should be reported with the sample results.

                         14. Method Performance

    14.1  The method detection limit (MDL) is defined as the minimum 
concentration of a substance that can be measured and reported with 99% 
confidence that the value is above zero.\1\ The MDL concentrations 
listed in Table 1 were obtained using reagent water.\10\ Similar results 
were achieved using representative wastewaters. The MDL actually 
achieved in a given analysis will vary depending on instrument 
sensitivity and matrix effects.
    14.2  This method has been tested for linearity of spike recovery 
from reagent water and has been demonstrated to be applicable over the 
concentration range from 7xMDL to 1000xMDL.\10\
    14.3  This method was tested by 18 laboratories using reagent water, 
drinking water, surface water, and three industrial wastewaters spiked 
at six concentrations over the range 1.0 to 515 [mu]g/L.\11\ Single 
operator precision, overall precision, and method accuracy were found to 
be directly related to the concentration of the parameter and 
essentially independent of the sample matrix. Linear equations to 
describe these relationships are presented in Table 3.

                               References

    1. 40 CFR part 136, appendix B.
    2. ``Determination of Nitroaromatic Compounds and Isophorone in 
Industrial and Municipal Wastewaters,'' EPA 600/ 4-82-024, National 
Technical Information Service, PB82-208398, Springfield, Virginia 22161, 
May 1982.
    3. ASTM Annual Book of Standards, Part 31, D3694-78. ``Standard 
Practices for Preparation of Sample Containers and for Preservation of 
Organic Constituents,'' American Society for Testing and Materials, 
Philadelphia.

[[Page 140]]

    4. ``Carcinogens--Working With Carcinogens,'' Department of Health, 
Education, and Welfare, Public Health Service, Center for Disease 
Control, National Institute for Occupational Safety and Health, 
Publication No. 77-206, August 1977.
    5. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR 
part 1910), Occupational Safety and Health Administration, OSHA 2206 
(Revised, January 1976).
    6. ``Safety in Academic Chemistry Laboratories,'' American Chemical 
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
    7. Provost, L.P., and Elder, R.S. ``Interpretation of Percent 
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44 
used in the equation in Section 8.3.3 is two times the value 1.22 
derived in this report.)
    8. ASTM Annual Book of Standards, Part 31, D3370-76. ``Standard 
Practices for Sampling Water,'' American Society for Testing and 
Materials, Philadelphia.
    9. Burke, J.A. ``Gas Chromatography for Pesticide Residue Analysis; 
Some Practical Aspects,'' Journal of the Association of Official 
Analytical Chemists, 48, 1037 (1965).
    10. ``Determination of Method Detection Limit and Analytical Curve 
for EPA Method 609--Nitroaromatics and Isophorone,'' Special letter 
report for EPA Contract 68-03-2624, U.S. Environmental Protection 
Agency, Environmental Monitoring and Support Laboratory, Cincinnati, 
Ohio 45268, June 1980.
    11. ``EPA Method Study 19, Method 609 (Nitroaromatics and 
Isophorone),'' EPA 600/4-84-018, National Technical Information Service, 
PB84-176908, Springfield, Virginia 22161, March 1984.

                         Table 1--Chromatographic Conditions and Method Detection Limits
----------------------------------------------------------------------------------------------------------------
                                                             Retention time (min)       Method detection limit
                                                         ----------------------------          ([mu]g/L)
                        Parameter                                                    ---------------------------
                                                             Col. 1        Col. 2         ECDGC         FIDGC
----------------------------------------------------------------------------------------------------------------
Nitrobenzene............................................        3.31          4.31         13.7           3.6
2,6-Dinitrotoluene......................................        3.52          4.75          0.01          -
Isophorone..............................................        4.49          5.72         15.7           5.7
2,4-Dinitrotoluene......................................        5.35          6.54          0.02          -
----------------------------------------------------------------------------------------------------------------
 AAColumn 1 conditions: Gas-Chrom Q (80/100 mesh) coated with 1.95% QF-1/1.5% OV-17 packed in a 1.2 m long x 2
  mm or 4 mm ID glass column. A 2 mm ID column and nitrogen carrier gas at 44 mL/min flow rate were used when
  determining isophorone and nitrobenzene by FIDGC. The column temperature was held isothermal at 85  deg.C. A 4
  mm ID column and 10% methane/90% argon carrier gas at 44 mL/min flow rate were used when determining the
  dinitrotoluenes by ECDGC. The column temperature was held isothermal at 145  deg.C.
 AAColumn 2 conditions: Gas-Chrom Q (80/100 mesh) coated with 3% OV-101 packed in a 3.0 m long x 2 mm or 4 mm ID
  glass column. A 2 mm ID column and nitrogen carrier gas at 44 mL/min flow rate were used when determining
  isophorone and nitrobenzene by FIDGC. The column temperature was held isothermal at 100  deg.C. A 4 mm ID
  column and 10% methane/90% argon carrier gas at 44 mL/min flow rate were used when determining the
  dinitrotoluenes by ECDGC. The column temperature was held isothermal at 150  deg.C.


                                   Table 2--QC Acceptance Criteria--Method 609
----------------------------------------------------------------------------------------------------------------
                                                                                        Range for X
                         Parameter                           Test Conc.   Limit for s    ([mu]g/L)    Range for
                                                             ([mu]g/L)     ([mu]g/L)                  P, Ps (%)
----------------------------------------------------------------------------------------------------------------
2,4-Dinitrotoluene........................................           20           5.1     3.6-22.8         6-125
2,6-Dinitrotoluene........................................           20           4.8     3.8-23.0         8-126
Isophorone................................................          100          32.3     8.0-100.0        D-117
Nitrobenzene..............................................          100          33.3    25.7-100.0        6-118
----------------------------------------------------------------------------------------------------------------
s=Standard deviation of four recovery measurements, in [mu]g/L (Section 8.2.4).
X=Average recovery for four recovery measurements, in [mu]g/L (Section 8.2.4).
P, Ps=Percent recovery measured (Section 8.3.2, Section 8.4.2).
D=Detected; result must be greater than zero.
 
Note: These criteria are based directly upon the method performance data in Table 3. Where necessary, the limits
  for recovery have been broadened to assure applicability of the limits to concentrations below those used to
  develop Table 3.


                Table 3--Method Accuracy and Precision as Functions of Concentration--Method 609
----------------------------------------------------------------------------------------------------------------
                                                            Accuracy, as      Single analyst        Overall
                       Parameter                            recovery, X'      precision, sr'     precision, S'
                                                             ([mu]g/L)          ([mu]g/L)          ([mu]g/L)
----------------------------------------------------------------------------------------------------------------
2,4-Dinitro-
  toluene..............................................         0.65C+0.22         0.20X+0.08         0.37X-0.07
2,6-Dinitro-
  toluene..............................................         0.66C+0.20         0.19X+0.06         0.36X-0.00
Isophorone.............................................         0.49C+2.93         0.28X+2.77         0.46X+0.31
Nitrobenzene...........................................         0.60C+2.00         0.25X+2.53         0.37X-0.78
----------------------------------------------------------------------------------------------------------------
X'=Expected recovery for one or more measurements of a sample containing a concentration of C, in [mu]g/L.
sr'=Expected single analyst standard deviation of measurements at an average concentration found of X, in [mu]g/
  L.
S'=Expected interlaboratory standard deviation of measurements at an average concentration found of X, in [mu]g/
  L.
C=True value for the concentration, in [mu]g/L.
X=Average recovery found for measurements of samples containing a concentration of C, in [mu]g/L.


[[Page 141]]

[GRAPHIC] [TIFF OMITTED] TC02JY92.029


[[Page 142]]

[GRAPHIC] [TIFF OMITTED] TC02JY92.030


[[Page 143]]

              Method 610--Polynuclear Aromatic Hydrocarbons

                        1. Scope and Application

    1.1  This method covers the determination of certain polynuclear 
aromatic hydrocarbons (PAH). The following parameters can be determined 
by this method:

------------------------------------------------------------------------
                  Parameter                    STORET No.      CAS No.
------------------------------------------------------------------------
Acenaphthene................................         34205       83-32-9
Acenaphthylene..............................         34200      208-96-8
Anthracene..................................         34220      120-12-7
Benzo(a)anthracene..........................         34526       56-55-3
Benzo(a)pyrene..............................         34247       50-32-8
Benzo(b)fluoranthene........................         34230      205-99-2
Benzo(ghi)perylene..........................         34521      191-24-2
Benzo(k)fluoranthene........................         34242      207-08-9
Chrysene....................................         34320      218-01-9
Dibenzo(a,h)anthracene......................         34556       53-70-3
Fluoranthene................................         34376      206-44-0
Fluorene....................................         34381       86-73-7
Indeno(1,2,3-cd)pyrene......................         34403      193-39-5
Naphthalene.................................         34696       91-20-3
Phenanthrene................................         34461       85-01-8
Pyrene......................................         34469      129-00-0
------------------------------------------------------------------------

    1.2  This is a chromatographic method applicable to the 
determination of the compounds listed above in municipal and industrial 
discharges as provided under 40 CFR 136.1. When this method is used to 
analyze unfamiliar samples for any or all of the compounds above, 
compound identifications should be supported by at least one additional 
qualitative technique. Method 625 provides gas chromatograph/mass 
spectrometer (GC/MS) conditions appropriate for the qualitative and 
quantitative confirmation of results for many of the parameters listed 
above, using the extract produced by this method.
    1.3  This method provides for both high performance liquid 
chromatographic (HPLC) and gas chromatographic (GC) approaches for the 
determination of PAHs. The gas chromatographic procedure does not 
adequately resolve the following four pairs of compounds: Anthracene and 
phenanthrene; chrysene and benzo(a)anthracene; benzo(b)fluoranthene and 
benzo(k)fluoranthene; and dibenzo(a,h) anthracene and indeno (1,2,3-
cd)pyrene. Unless the purpose for the analysis can be served by 
reporting the sum of an unresolved pair, the liquid chromatographic 
approach must be used for these compounds. The liquid chromatographic 
method does resolve all 16 of the PAHs listed.
    1.4  The method detection limit (MDL, defined in Section 15.1) \1\ 
for each parameter is listed in Table 1. The MDL for a specific 
wastewater may differ from those listed, depending upon the nature of 
interferences in the sample matrix.
    1.5  The sample extraction and concentration steps in this method 
are essentially the same as in Methods 606, 608, 609, 611, and 612. 
Thus, a single sample may be extracted to measure the parameters 
included in the scope of each of these methods. When cleanup is 
required, the concentration levels must be high enough to permit 
selecting aliquots, as necessary, to apply appropriate cleanup 
procedures. Selection of the aliquots must be made prior to the solvent 
exchange steps of this method. The analyst is allowed the latitude, 
under Sections 12 and 13, to select chromatographic conditions 
appropriate for the simultaneous measurement of combinations of these 
parameters.
    1.6  Any modification of this method, beyond those expressly 
permitted, shall be considered as a major modification subject to 
application and approval of alternate test procedures under 40 CFR 136.4 
and 136.5.
    1.7  This method is restricted to use by or under the supervision of 
analysts experienced in the use of HPLC and GC systems and in the 
interpretation of liquid and gas chromatograms. Each analyst must 
demonstrate the ability to generate acceptable results with this method 
using the procedure described in Section 8.2.

                          2. Summary of Method

    2.1  A measured volume of sample, approximately 1-L, is extracted 
with methylene chloride using a separatory funnel. The methylene 
chloride extract is dried and concentrated to a volume of 10 mL or less. 
The extract is then separated by HPLC or GC. Ultraviolet (UV) and 
fluorescence detectors are used with HPLC to identify and measure the 
PAHs. A flame ionization detector is used with GC.\2\
    2.2  The method provides a silica gel column cleanup procedure to 
aid in the elimination of interferences that may be encountered.

                            3. Interferences

    3.1  Method interferences may be caused by contaminants in solvents, 
reagents, glassware, and other sample processing hardward that lead to 
discrete artifacts and/or elevated baselines in the chromatograms. All 
of these materials must be routinely demonstrated to be free from 
interferences under the conditions of the analysis by running laboratory 
reagent blanks as described in Section 8.1.3.
    3.1.1  Glassware must be scrupulously cleaned.\3\ Clean all 
glassware as soon as possible after use by rinsing with the last solvent 
used in it. Solvent rinsing should be followed by detergent washing with 
hot water, and rinses with tap water and distilled water. The glassware 
should then be drained dry, and heated in a muffle furnace at 400  deg.C 
for 15 to 30 min. Some thermally stable materials, such as PCBs, may not 
be eliminated by this treatment. Solvent rinses with acetone and 
pesticide quality hexane may be

[[Page 144]]

substituted for the muffle furnace heating. Thorough rinsing with such 
solvents usually eliminates PCB interference. Volumetric ware should not 
be heated in a muffle furnace. After drying and cooling, glassware 
should be sealed and stored in a clean environment to prevent any 
accumulation of dust or other contaminants. Store inverted or capped 
with aluminum foil.
    3.1.2  The use of high purity reagents and solvents helps to 
minimize interference problems. Purification of solvents by distillation 
in all-glass systems may be required.
    3.2  Matrix interferences may be caused by contaminants that are co-
extracted from the sample. The extent of matrix interferences will vary 
considerably from source to source, depending upon the nature and 
diversity of the industrial complex or municipality being sampled. The 
cleanup procedure in Section 11 can be used to overcome many of these 
interferences, but unique samples may require additional cleanup 
approaches to achieve the MDL listed in Table 1.
    3.3  The extent of interferences that may be encountered using 
liquid chromatographic techniques has not been fully assessed. Although 
the HPLC conditions described allow for a unique resolution of the 
specific PAH compounds covered by this method, other PAH compounds may 
interfere.

                                4. Safety

    4.1  The toxicity or carcinogenicity of each reagent used in this 
method have not been precisely defined; however, each chemical compound 
should be treated as a potential health hazard. From this viewpoint, 
exposure to these chemicals must be reduced to the lowest possible level 
by whatever means available. The laboratory is responsible for 
maintaining a current awareness file of OSHA regulations regarding the 
safe handling of the chemicals specified in this method. A reference 
file of material data handling sheets should also be made available to 
all personnel involved in the chemical analysis. Additional references 
to laboratory safety are available and have been identified 
\4\-\6\ for the information of the analyst.
    4.2  The following parameters covered by this method have been 
tentatively classified as known or suspected, human or mammalian 
carcinogens: benzo(a)anthracene, benzo(a)pyrene, and dibenzo(a,h)-
anthracene. Primary standards of these toxic compounds should be 
prepared in a hood. A NIOSH/MESA approved toxic gas respirator should be 
worn when the analyst handles high concentrations of these toxic 
compounds.

                       5. Apparatus and Materials

    5.1  Sampling equipment, for discrete or composite sampling.
    5.1.1  Grab sample bottle--1-L or 1-qt, amber glass, fitted with a 
screw cap lined with Teflon. Foil may be substituted for Teflon if the 
sample is not corrosive. If amber bottles are not available, protect 
samples from light. The bottle and cap liner must be washed, rinsed with 
acetone or methylene chloride, and dried before use to minimize 
contamination.
    5.1.2  Automatic sampler (optional)--The sampler must incorporate 
glass sample containers for the collection of a minimum of 250 mL of 
sample. Sample containers must be kept refrigerated at 4  deg.C and 
protected from light during compositing. If the sampler uses a 
peristaltic pump, a minimum length of compressible silicone rubber 
tubing may be used. Before use, however, the compressible tubing should 
be thoroughly rinsed with methanol, followed by repeated rinsings with 
distilled water to minimize the potential for contamination of the 
sample. An integrating flow meter is required to collect flow 
proportional composites.
    5.2  Glassware (All specifications are suggested. Catalog numbers 
are included for illustration only.):
    5.2.1  Separatory funnel--2-L, with Teflon stopcock.
    5.2.2  Drying column--Chromatographic column, approximately 400 mm 
long x 19 mm ID, with coarse frit filter disc.
    5.2.3  Concentrator tube, Kuderna-Danish--10-mL, graduated (Kontes 
K-570050-1025 or equivalent). Calibration must be checked at the volumes 
employed in the test. Ground glass stopper is used to prevent 
evaporation of extracts.
    5.2.4  Evaporative flask, Kuderna-Danish--500-mL (Kontes K-570001-
0500 or equivalent). Attach to concentrator tube with springs.
    5.2.5  Snyder column, Kuderna-Danish--Three-ball macro (Kontes K-
503000-0121 or equivalent).
    5.2.6  Snyder column, Kuderna-Danish--Two-ball micro (Kontes K-
569001-0219 or equivalent).
    5.2.7  Vials--10 to 15-mL, amber glass, with Teflon-lined screw cap.
    5.2.8  Chromatographic column--250 mm long x 10 mm ID, with coarse 
frit filter disc at bottom and Teflon stopcock.
    5.3  Boiling chips--Approximately 10/40 mesh. Heat to 400  deg.C for 
30 min or Soxhlet extract with methylene chloride.
    5.4  Water bath--Heated, with concentric ring cover, capable of 
temperature control (2  deg.C). The bath should be used in a 
hood.
    5.5  Balance--Analytical, capable of accurately weighing 0.0001 g.
    5.6  High performance liquid chromatograph (HPLC)--An analytical 
system complete with column supplies, high pressure syringes, detectors, 
and compatible strip-chart recorder. A data system is recommended for 
measuring peak areas and retention times.
    5.6.1  Gradient pumping system--Constant flow.

[[Page 145]]

    5.6.2  Reverse phase column--HC-ODS Sil-X, 5 micron particle 
diameter, in a 25 cm x 2.6 mm ID stainless steel column (Perkin Elmer 
No. 089-0716 or equivalent). This column was used to develop the method 
performance statements in Section 15. Guidelines for the use of 
alternate column packings are provided in Section 12.2.
    5.6.3  Detectors--Fluorescence and/or UV detectors. The fluorescence 
detector is used for excitation at 280 nm and emission greater than 389 
nm cutoff (Corning 3-75 or equivalent). Fluorometers should have 
dispersive optics for excitation and can utilize either filter or 
dispersive optics at the emission detector. The UV detector is used at 
254 nm and should be coupled to the fluorescence detector. These 
detectors were used to develop the method performance statements in 
Section 15. Guidelines for the use of alternate detectors are provided 
in Section 12.2.
    5.7  Gas chromatograph--An analytical system complete with 
temperature programmable gas chromatograph suitable for on-column or 
splitless injection and all required accessories including syringes, 
analytical columns, gases, detector, and strip-chart recorder. A data 
system is recommended for measuring peak areas.
    5.7.1  Column--1.8 m long x 2 mm ID glass, packed with 3% OV-17 on 
Chromosorb W-AW-DCMS (100/120 mesh) or equivalent. This column was used 
to develop the retention time data in Table 2. Guidelines for the use of 
alternate column packings are provided in Section 13.3.
    5.7.2  Detector--Flame ionization detector. This detector has proven 
effective in the analysis of wastewaters for the parameters listed in 
the scope (Section 1.1), excluding the four pairs of unresolved 
compounds listed in Section 1.3. Guidelines for the use of alternate 
detectors are provided in Section 13.3.

                               6. Reagents

    6.1  Reagent water--Reagent water is defined as a water in which an 
interferent is not observed at the MDL of the parameters of interest.
    6.2  Sodium thiosulfate--(ACS) Granular.
    6.3  Cyclohexane, methanol, acetone, methylene chloride, pentane--
Pesticide quality or equivalent.
    6.4  Acetonitrile--HPLC quality, distilled in glass.
    6.5  Sodium sulfate--(ACS) Granular, anhydrous. Purify by heating at 
400  deg.C for 4 h in a shallow tray.
    6.6  Silica gel--100/200 mesh, desiccant, Davison, grade-923 or 
equivalent. Before use, activate for at least 16 h at 130  deg.C in a 
shallow glass tray, loosely covered with foil.
    6.7  Stock standard solutions (1.00 [mu]g/[mu]L)--Stock standard 
solutions can be prepared from pure standard materials or purchased as 
certified solutions.
    6.7.1  Prepare stock standard solutions by accurately weighing about 
0.0100 g of pure material. Dissolve the material in acetonitrile and 
dilute to volume in a 10-mL volumetric flask. Larger volumes can be used 
at the convenience of the analyst. When compound purity is assayed to be 
96% or greater, the weight can be used without correction to calculate 
the concentration of the stock standard. Commercially prepared stock 
standards can be used at any concentration if they are certified by the 
manufacturer or by an independent source.
    6.7.2  Transfer the stock standard solutions into Teflon-sealed 
screw-cap bottles. Store at 4  deg.C and protect from light. Stock 
standard solutions should be checked frequently for signs of degradation 
or evaporation, especially just prior to preparing calibration standards 
from them.
    6.7.3  Stock standard solutions must be replaced after six months, 
or sooner if comparison with check standards indicates a problem.
    6.8  Quality control check sample concentrate--See Section 8.2.1.

                             7. Calibration

    7.1  Establish liquid or gas chromatographic operating conditions 
equivalent to those given in Table 1 or 2. The chromatographic system 
can be calibrated using the external standard technique (Section 7.2) or 
the internal standard technique (Section 7.3).
    7.2  External standard calibration procedure:
    7.2.1  Prepare calibration standards at a minimum of three 
concentration levels for each parameter of interest by adding volumes of 
one or more stock standards to a volumetric flask and diluting to volume 
with acetonitrile. One of the external standards should be at a 
concentration near, but above, the MDL (Table 1) and the other 
concentrations should correspond to the expected range of concentrations 
found in real samples or should define the working range of the 
detector.
    7.2.2  Using injections of 5 to 25 [mu]L for HPLC and 2 to 5 [mu]L 
for GC, analyze each calibration standard according to Section 12 or 13, 
as appropriate. Tabulate peak height or area responses against the mass 
injected. The results can be used to prepare a calibration curve for 
each compound. Alternatively, if the ratio of response to amount 
injected (calibration factor) is a constant over the working range (<10% 
relative standard deviation, RSD), linearity through the origin can be 
assumed and the average ratio or calibration factor can be used in place 
of a calibration curve.
    7.3  Internal standard calibration procedure--To use this approach, 
the analyst must select one or more internal standards that are similar 
in analytical behavior to the

[[Page 146]]

compounds of interest. The analyst must further demonstrate that the 
measurement of the internal standard is not affected by method or matrix 
interferences. Because of these limitations, no internal standard can be 
suggested that is applicable to all samples.
    7.3.1  Prepare calibration standards at a minimum of three 
concentration levels for each parameter of interest by adding volumes of 
one or more stock standards to a volumetric flask. To each calibration 
standard, add a known constant amount of one or more internal standards, 
and dilute to volume with acetonitrile. One of the standards should be 
at a concentration near, but above, the MDL and the other concentrations 
should correspond to the expected range of concentrations found in real 
samples or should define the working range of the detector.
    7.3.2  Using injections of 5 to 25 [mu]L for HPLC and 2 to 5 [mu]L 
for GC, analyze each calibration standard according to Section 12 or 13, 
as appropriate. Tabulate peak height or area responses against 
concentration for each compound and internal standard. Calculate 
response factors (RF) for each compound using Equation 1.
[GRAPHIC] [TIFF OMITTED] TC15NO91.113

                                                              Equation 1

where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Cis=Concentration of the internal standard ([mu]g/L).
Cs=Concentration of the parameter to be measured ([mu]g/L).

If the RF value over the working range is a constant (<10% RSD), the RF 
can be assumed to be invariant and the average RF can be used for 
calculations. Alternatively, the results can be used to plot a 
calibration curve of response ratios, As/Ais, vs. 
RF.

    7.4  The working calibration curve, calibration factor, or RF must 
be verified on each working day by the measurement of one or more 
calibration standards. If the response for any parameter varies from the 
predicted response by more than 15%, the test must be 
repeated using a fresh calibration standard. Alternatively, a new 
calibration curve must be prepared for that compound.
    7.5  Before using any cleanup procedure, the analyst must process a 
series of calibration standards through the procedure to validate 
elution patterns and the absence of interferences from the reagents.

                           8. Quality Control

    8.1  Each laboratory that uses this method is required to operate a 
formal quality control program. The minimum requirements of this program 
consist of an initial demonstration of laboratory capability and an 
ongoing analysis of spiked samples to evaluate and document data 
quality. The laboratory must maintain records to document the quality of 
data that is generated. Ongoing data quality checks are compared with 
established performance criteria to determine if the results of analyses 
meet the performance characteristics of the method. When results of 
sample spikes indicate atypical method performance, a quality control 
check standard must be analyzed to confirm that the measurements were 
performed in an in-control mode of operation.
    8.1.1  The analyst must make an initial, one-time, demonstration of 
the ability to generate acceptable accuracy and precision with this 
method. This ability is established as described in Section 8.2.
    8.1.2  In recognition of advances that are occurring in 
chromatography, the analyst is permitted certain options (detailed in 
Sections 10.4, 11.1, 12.2, and 13.3) to improve the separations or lower 
the cost of measurements. Each time such a modification is made to the 
method, the analyst is required to repeat the procedure in Section 8.2.
    8.1.3  Before processing any samples the analyst must analyze a 
reagent water blank to demonstrate that interferences from the 
analytical system and glassware are under control. Each time a set of 
samples is extracted or reagents are changed a reagent water blank must 
be processed as a safeguard against laboratory contamination.
    8.1.4  The laboratory must, on an ongoing basis, spike and analyze a 
minimum of 10% of all samples to monitor and evaluate laboratory data 
quality. This procedure is described in Section 8.3.
    8.1.5  The laboratory must, on an ongoing basis, demonstrate through 
the analyses of quality control check standards that the operation of 
the measurement system is in control. This procedure is described in 
Section 8.4. The frequency of the check standard analyses is equivalent 
to 10% of all samples analyzed but may be reduced if spike recoveries 
from samples (Section 8.3) meet all specified quality control criteria.
    8.1.6  The laboratory must maintain performance records to document 
the quality of data that is generated. This procedure is described in 
Section 8.5.
    8.2  To establish the ability to generate acceptable accuracy and 
precision, the analyst must perform the following operations.
    8.2.1  A quality control (QC) check sample concentrate is required 
containing each parameter of interest at the following concentrations in 
acetonitrile: 100 [mu]g/mL of any

[[Page 147]]

of the six early-eluting PAHs (naphthalene, acenaphthylene, 
acenaphthene, fluorene, phenanthrene, and anthracene); 5 [mu]g/mL of 
benzo(k)fluoranthene; and 10 [mu]g/mL of any of the other PAHs. The QC 
check sample concentrate must be obtained from the U.S. Environmental 
Protection Agency, Environmental Monitoring and Support Laboratory in 
Cincinnati, Ohio, if available. If not available from that source, the 
QC check sample concentrate must be obtained from another external 
source. If not available from either source above, the QC check sample 
concentrate must be prepared by the laboratory using stock standards 
prepared independently from those used for calibration.
    8.2.2  Using a pipet, prepare QC check samples at the test 
concentrations shown in Table 3 by adding 1.00 mL of QC check sample 
concentrate to each of four 1-L aliquots of reagent water.
    8.2.3  Analyze the well-mixed QC check samples according to the 
method beginning in Section 10.
    8.2.4  Calculate the average recovery (X) in [mu]g/L, and the 
standard deviation of the recovery (s) in [mu]g/L, for each parameter 
using the four results.
    8.2.5  For each parameter compare s and X with the corresponding 
acceptance criteria for precision and accuracy, respectively, found in 
Table 3. If s and X for all parameters of interest meet the acceptance 
criteria, the system performance is acceptable and analysis of actual 
samples can begin. If any individual s exceeds the precision limit or 
any individual X falls outside the range for accuracy, the system 
performance is unacceptable for that parameter.
    Note: The large number of parameters in Table 3 present a 
substantial probability that one or more will fail at least one of the 
acceptance criteria when all parameters are analyzed.
    8.2.6  When one or more of the parameters tested fail at least one 
of the acceptance criteria, the analyst must proceed according to 
Section 8.2.6.1 or 8.2.6.2.
    8.2.6.1  Locate and correct the source of the problem and repeat the 
test for all parameters of interest beginning with Section 8.2.2.
    8.2.6.2  Beginning with Section 8.2.2, repeat the test only for 
those parameters that failed to meet criteria. Repeated failure, 
however, will confirm a general problem with the measurement system. If 
this occurs, locate and correct the source of the problem and repeat the 
test for all compounds of interest beginning with Section 8.2.2.
    8.3  The laboratory must, on an ongoing basis, spike at least 10% of 
the samples from each sample site being monitored to assess accuracy. 
For laboratories analyzing one to ten samples per month, at least one 
spiked sample per month is required.
    8.3.1  The concentration of the spike in the sample should be 
determined as follows:
    8.3.1.1  If, as in compliance monitoring, the concentration of a 
specific parameter in the sample is being checked against a regulatory 
concentration limit, the spike should be at that limit or 1 to 5 times 
higher than the background concentration determined in Section 8.3.2, 
whichever concentration would be larger.
    8.3.1.2  If the concentration of a specific parameter in the sample 
is not being checked against a limit specific to that parameter, the 
spike should be at the test concentration in Section 8.2.2 or 1 to 5 
times higher than the background concentration determined in Section 
8.3.2, whichever concentration would be larger.
    8.3.1.3  If it is impractical to determine background levels before 
spiking (e.g., maximum holding times will be exceeded), the spike 
concentration should be (1) the regulatory concentration limit, if any; 
or, if none, (2) the larger of either 5 times higher than the expected 
background concentration or the test concentration in Section 8.2.2.
    8.3.2  Analyze one sample aliquot to determine the background 
concentration (B) of each parameter. If necessary, prepare a new QC 
check sample concentrate (Section 8.2.1) appropriate for the background 
concentrations in the sample. Spike a second sample aliquot with 1.0 mL 
of the QC check sample concentrate and analyze it to determine the 
concentration after spiking (A) of each parameter. Calculate each 
percent recovery (P) as 100 (A-B)%/T, where T is the known true value of 
the spike.
    8.3.3  Compare the percent recovery (P) for each parameter with the 
corresponding QC acceptance criteria found in Table 3. These acceptance 
criteria were calculated to include an allowance for error in 
measurement of both the background and spike concentrations, assuming a 
spike to background ratio of 5:1. This error will be accounted for to 
the extent that the analyst's spike to background ratio approaches 
5:1.\7\ If spiking was performed at a concentration lower than the test 
concentration in Section 8.2.2, the analyst must use either the QC 
acceptance criteria in Table 3, or optional QC acceptance criteria 
calculated for the specific spike concentration. To calculate optional 
acceptance criteria for the recovery of a parameter: (1) Calculate 
accuracy (X') using the equation in Table 4, substituting the spike 
concentration (T) for C; (2) calculate overall precision (S') using the 
equation in Table 4, substituting X' for X; (3) calculate the range for 
recovery at the spike concentration as (100 X'/T)2.44(100 
S'/T)%.\7\
    8.3.4  If any individual P falls outside the designated range for 
recovery, that parameter has failed the acceptance criteria. A check 
standard containing each parameter

[[Page 148]]

that failed the critiera must be analyzed as described in Section 8.4.
    8.4  If any parameter fails the acceptance criteria for recovery in 
Section 8.3, a QC check standard containing each parameter that failed 
must be prepared and analyzed.
    Note: The frequency for the required analysis of a QC check standard 
will depend upon the number of parameters being simultaneously tested, 
the complexity of the sample matrix, and the performance of the 
laboratory. If the entire list of parameters in Table 3 must be measured 
in the sample in Section 8.3, the probability that the analysis of a QC 
check standard will be required is high. In this case the QC check 
standard should be routinely analyzed with the spike sample.
    8.4.1  Prepare the QC check standard by adding 1.0 mL of QC check 
sample concentrate (Section 8.2.1 or 8.3.2) to 1 L of reagent water. The 
QC check standard needs only to contain the parameters that failed 
criteria in the test in Section 8.3.
    8.4.2  Analyze the QC check standard to determine the concentration 
measured (A) of each parameter. Calculate each percent recovery 
(Ps) as 100 (A/T)%, where T is the true value of the standard 
concentration.
    8.4.3  Compare the percent recovery (Ps) for each 
parameter with the corresponding QC acceptance criteria found in Table 
3. Only parameters that failed the test in Section 8.3 need to be 
compared with these criteria. If the recovery of any such parameter 
falls outside the designated range, the laboratory performance for that 
parameter is judged to be out of control, and the problem must be 
immediately identified and corrected. The analytical result for that 
parameter in the unspiked sample is suspect and may not be reported for 
regulatory compliance purposes.
    8.5  As part of the QC program for the laboratory, method accuracy 
for wastewater samples must be assessed and records must be maintained. 
After the analysis of five spiked wastewater samples as in Section 8.3, 
calculate the average percent recovery (P) and the standard deviation of 
the percent recovery (sp). Express the accuracy assessment as 
a percent recovery interval from P-2sp to P+2sp. 
If P=90% and sp=10%, for example, the accuracy interval is 
expressed as 70-110%. Update the accuracy assessment for each parameter 
on a regular basis (e.g. after each five to ten new accuracy 
measurements).
    8.6  It is recommended that the laboratory adopt additional quality 
assurance practices for use with this method. The specific practices 
that are most productive depend upon the needs of the laboratory and the 
nature of the samples. Field duplicates may be analyzed to assess the 
precision of the environmental measurements. When doubt exists over the 
identification of a peak on the chromatogram, confirmatory techniques 
such as gas chromatography with a dissimilar column, specific element 
detector, or mass spectrometer must be used. Whenever possible, the 
laboratory should analyze standard reference materials and participate 
in relevant performance evaluation studies.

            9. Sample Collection, Preservation, and Handling

    9.1  Grab samples must be collected in glass containers. 
Conventional sampling practices \8\ should be followed, except that the 
bottle must not be prerinsed with sample before collection. Composite 
samples should be collected in refrigerated glass containers in 
accordance with the requirements of the program. Automatic sampling 
equipment must be as free as possible of Tygon tubing and other 
potential sources of contamination.
    9.2  All samples must be iced or refrigerated at 4  deg.C from the 
time of collection until extraction. PAHs are known to be light 
sensitive; therefore, samples, extracts, and standards should be stored 
in amber or foil-wrapped bottles in order to minimize photolytic 
decomposition. Fill the sample bottles and, if residual chlorine is 
present, add 80 mg of sodium thiosulfate per liter of sample and mix 
well. EPA Methods 330.4 and 330.5 may be used for measurement of 
residual chlorine.\9\ Field test kits are available for this purpose.
    9.3  All samples must be extracted within 7 days of collection and 
completely analyzed within 40 days of extraction.\2\

                          10. Sample Extraction

    10.1  Mark the water meniscus on the side of the sample bottle for 
later determination of sample volume. Pour the entire sample into a 2-L 
separatory funnel.
    10.2  Add 60 mL of methylene chloride to the sample bottle, seal, 
and shake 30 s to rinse the inner surface. Transfer the solvent to the 
separatory funnel and extract the sample by shaking the funnel for 2 
min. with periodic venting to release excess pressure. Allow the organic 
layer to separate from the water phase for a minimum of 10 min. If the 
emulsion interface between layers is more than one-third the volume of 
the solvent layer, the analyst must employ mechanical techniques to 
complete the phase separation. The optimum technique depends upon the 
sample, but may include stirring, filtration of the emulsion through 
glass wool, centrifugation, or other physical methods. Collect the 
methylene chloride extract in a 250-mL Erlenmeyer flask.
    10.3  Add a second 60-mL volume of methylene chloride to the sample 
bottle and repeat the extraction procedure a second time, combining the 
extracts in the Erlenmeyer flask. Perform a third extraction in the same 
manner.

[[Page 149]]

    10.4  Assemble a Kuderna-Danish (K-D) concentrator by attaching a 
10-mL concentrator tube to a 500-mL evaporative flask. Other 
concentration devices or techniques may be used in place of the K-D 
concentrator if the requirements of Section 8.2 are met.
    10.5  Pour the combined extract through a solvent-rinsed drying 
column containing about 10 cm of anhydrous sodium sulfate, and collect 
the extract in the K-D concentrator. Rinse the Erlenmeyer flask and 
column with 20 to 30 mL of methylene chloride to complete the 
quantitative transfer.
    10.6  Add one or two clean boiling chips to the evaporative flask 
and attach a three-ball Snyder column. Prewet the Snyder column by 
adding about 1 mL of methylene chloride to the top. Place the K-D 
apparatus on a hot water bath (60 to 65  deg.C) so that the concentrator 
tube is partially immersed in the hot water, and the entire lower 
rounded surface of the flask is bathed with hot vapor. Adjust the 
vertical position of the apparatus and the water temperature as required 
to complete the concentration in 15 to 20 min. At the proper rate of 
distillation the balls of the column will actively chatter but the 
chambers will not flood with condensed solvent. When the apparent volume 
of liquid reaches 1 mL, remove the K-D apparatus and allow it to drain 
and cool for at least 10 min.
    10.7  Remove the Snyder column and rinse the flask and its lower 
joint into the concentrator tube with 1 to 2 mL of methylene chloride. A 
5-mL syringe is recommended for this operation. Stopper the concentrator 
tube and store refrigerated if further processing will not be performed 
immediately. If the extract will be stored longer than two days, it 
should be transferred to a Teflon-sealed screw-cap vial and protected 
from light. If the sample extract requires no further cleanup, proceed 
with gas or liquid chromatographic analysis (Section 12 or 13). If the 
sample requires further cleanup, proceed to Section 11.
    10.8  Determine the original sample volume by refilling the sample 
bottle to the mark and transferring the liquid to a 1000-mL graduated 
cylinder. Record the sample volume to the nearest 5 mL.

                       11. Cleanup and Separation

    11.1  Cleanup procedures may not be necessary for a relatively clean 
sample matrix. If particular circumstances demand the use of a cleanup 
procedure, the analyst may use the procedure below or any other 
appropriate procedure. However, the analyst first must demonstrate that 
the requirements of Section 8.2 can be met using the methods as revised 
to incorporate the cleanup procedure.
    11.2  Before the silica gel cleanup technique can be utilized, the 
extract solvent must be exchanged to cyclohexane. Add 1 to 10 mL of the 
sample extract (in methylene chloride) and a boiling chip to a clean K-D 
concentrator tube. Add 4 mL of cyclohexane and attach a two-ball micro-
Snyder column. Prewet the column by adding 0.5 mL of methylene chloride 
to the top. Place the micro-K-D apparatus on a boiling (100  deg.C) 
water bath so that the concentrator tube is partially immersed in the 
hot water. Adjust the vertical position of the apparatus and the water 
temperature as required to complete concentration in 5 to 10 min. At the 
proper rate of distillation the balls of the column will actively 
chatter but the chambers will not flood. When the apparent volume of the 
liquid reaches 0.5 mL, remove the K-D apparatus and allow it to drain 
and cool for at least 10 min. Remove the micro-Snyder column and rinse 
its lower joint into the concentrator tube with a minimum amount of 
cyclohexane. Adjust the extract volume to about 2 mL.
    11.3  Silica gel column cleanup for PAHs:
    11.3.1  Prepare a slurry of 10 g of activiated silica gel in 
methylene chloride and place this into a 10-mm ID chromatographic 
column. Tap the column to settle the silica gel and elute the methylene 
chloride. Add 1 to 2 cm of anhydrous sodium sulfate to the top of the 
silica gel.
    11.3.2  Preelute the column with 40 mL of pentane. The rate for all 
elutions should be about 2 mL/min. Discard the eluate and just prior to 
exposure of the sodium sulfate layer to the air, transfer the 2-mL 
cyclohexane sample extract onto the column using an additional 2 mL 
cyclohexane to complete the transfer. Just prior to exposure of the 
sodium sulfate layer to the air, add 25 mL of pentane and continue the 
elution of the column. Discard this pentane eluate.
    11.3.3  Next, elute the column with 25 mL of methylene chloride/
pentane (4+6)(V/V) into a 500-mL K-D flask equipped with a 10-mL 
concentrator tube. Concentrate the collected fraction to less than 10 mL 
as in Section 10.6. When the apparatus is cool, remove the Snyder column 
and rinse the flask and its lower joint with pentane. Proceed with HPLC 
or GC analysis.

               12. High Performance Liquid Chromatography

    12.1  To the extract in the concentrator tube, add 4 mL of 
acetonitrile and a new boiling chip, then attach a two-ball micro-Snyder 
column. Concentrate the solvent as in Section 10.6, except set the water 
bath at 95 to 100  deg.C. When the apparatus is cool, remove the micro-
Snyder column and rinse its lower joint into the concentrator tube with 
about 0.2 mL of acetonitrile. Adjust the extract volume to 1.0 mL.
    12.2  Table 1 summarizes the recommended operating conditions for 
the HPLC. Included in this table are retention times, capacity factors, 
and MDL that can be achieved under

[[Page 150]]

these conditions. The UV detector is recommended for the determination 
of naphthalene, acenaphthylene, acenapthene, and fluorene and the 
fluorescence detector is recommended for the remaining PAHs. Examples of 
the separations achieved by this HPLC column are shown in Figures 1 and 
2. Other HPLC columns, chromatographic conditions, or detectors may be 
used if the requirements of Section 8.2 are met.
    12.3  Calibrate the system daily as described in Section 7.
    12.4  If the internal standard calibration procedure is being used, 
the internal standard must be added to the sample extract and mixed 
thoroughly immediately before injection into the instrument.
    12.5  Inject 5 to 25 [mu]L of the sample extract or standard into 
the HPLC using a high pressure syringe or a constant volume sample 
injection loop. Record the volume injected to the nearest 0.1 [mu]L, and 
the resulting peak size in area or peak height units. Re-equilibrate the 
HPLC column at the initial gradient conditions for at least 10 min 
between injections.
    12.6  Identify the parameters in the sample by comparing the 
retention time of the peaks in the sample chromatogram with those of the 
peaks in standard chromatograms. The width of the retention time window 
used to make identifications should be based upon measurements of actual 
retention time variations of standards over the course of a day. Three 
times the standard deviation of a retention time for a compound can be 
used to calculate a suggested window size; however, the experience of 
the analyst should weigh heavily in the interpretation of chromatograms.
    12.7  If the response for a peak exceeds the working range of the 
system, dilute the extract with acetonitrile and reanalyze.
    12.8  If the measurement of the peak response is prevented by the 
presence of interferences, further cleanup is required.

                         13. Gas Chromatography

    13.1  The packed column GC procedure will not resolve certain 
isomeric pairs as indicated in Section 1.3 and Table 2. The liquid 
chromatographic procedure (Section 12) must be used for these 
parameters.
    13.2  To achieve maximum sensitivity with this method, the extract 
must be concentrated to 1.0 mL. Add a clean boiling chip to the 
methylene chloride extract in the concentrator tube. Attach a two-ball 
micro-Snyder column. Prewet the micro-Snyder column by adding about 0.5 
mL of methylene chloride to the top. Place the micro-K-D apparatus on a 
hot water bath (60 to 65  deg.C) so that the concentrator tube is 
partially immersed in the hot water. Adjust the vertical position of the 
apparatus and the water temperature as required to complete the 
concentration in 5 to 10 min. At the proper rate of distillation the 
balls will actively chatter but the chambers will not flood. When the 
apparent volume of liquid reaches 0.5 mL, remove the K-D apparatus and 
allow it to drain and cool for at least 10 min. Remove the micro-Snyder 
column and rinse its lower joint into the concentrator tube with a 
minimum amount of methylene chloride. Adjust the final volume to 1.0 mL 
and stopper the concentrator tube.
    13.3  Table 2 summarizes the recommended operating conditions for 
the gas chromatograph. Included in this table are retention times that 
were obtained under these conditions. An example of the separations 
achieved by this column is shown in Figure 3. Other packed or capillary 
(open-tubular) columns, chromatographic conditions, or detectors may be 
used if the requirements of Section 8.2 are met.
    13.4  Calibrate the gas chromatographic system daily as described in 
Section 7.
    13.5  If the internal standard calibration procedure is being used, 
the internal standard must be added to the sample extract and mixed 
thoroughly immediately before injection into the gas chromatograph.
    13.6  Inject 2 to 5 [mu]L of the sample extract or standard into the 
gas chromatograph using the solvent-flush technique.\10\ Smaller (1.0 
[mu]L) volumes may be injected if automatic devices are employed. Record 
the volume injected to the nearest 0.05 [mu]L, and the resulting peak 
size in area or peak height units.
    13.7  Identify the parameters in the sample by comparing the 
retention times of the peaks in the sample chromatogram with those of 
the peaks in standard chromatograms. The width of the retention time 
window used to make identifications should be based upon measurements of 
actual retention time variations of standards over the course of a day. 
Three times the standard deviation of a retention time for a compound 
can be used to calculate a suggested window size; however, the 
experience of the analyst should weigh heavily in the interpretation of 
chromatograms.
    13.8  If the response for a peak exceeds the working range of the 
system, dilute the extract and reanalyze.
    13.9  If the measurement of the peak response is prevented by the 
presence of interferences, further cleanup is required.

                            14. Calculations

    14.1  Determine the concentration of individual compounds in the 
sample.
    14.1.1  If the external standard calibration procedure is used, 
calculate the amount of material injected from the peak response using 
the calibration curve or calibration factor determined in Section 7.2.2. 
The concentration in the sample can be calculated from Equation 2.

[[Page 151]]

[GRAPHIC] [TIFF OMITTED] TC15NO91.114

                                                              Equation 2

where:
A=Amount of material injected (ng).
Vi=Volume of extract injected ([mu]L).
Vt=Volume of total extract ([mu]L).
Vs=Volume of water extracted (mL).

    13.1.2  If the internal standard calibration procedure is used, 
calculate the concentration in the sample using the response factor (RF) 
determined in Section 7.3.2 and Equation 3.
[GRAPHIC] [TIFF OMITTED] TC15NO91.115

                                                              Equation 3

where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Is=Amount of internal standard added to each extract ([mu]g).
Vo=Volume of water extracted (L).

    14.2  Report results in [mu]g/L without correction for recovery 
data. All QC data obtained should be reported with the sample results.

                         15. Method Performance

    15.1  The method detection limit (MDL) is defined as the minimum 
concentration of a substance that can be measured and reported with 99% 
confidence that the value is above zero.\1\ The MDL concentrations 
listed in Table 1 were obtained using reagent water.\11\ Similar results 
were achieved using representative wastewaters. MDL for the GC approach 
were not determined. The MDL actually achieved in a given analysis will 
vary depending on instrument sensitivity and matrix effects.
    15.2  This method has been tested for linearity of spike recovery 
from reagent water and has been demonstrated to be applicable over the 
concentration range from 8 x MDL to 800 x MDL\11\ with the following 
exception: benzo(ghi)perylene recovery at 80 x and 800 x MDL were low 
(35% and 45%, respectively).
    15.3  This method was tested by 16 laboratories using reagent water, 
drinking water, surface water, and three industrial wastewaters spiked 
at six concentrations over the range 0.1 to 425 [mu]g/L.\12\ Single 
operator precision, overall precision, and method accuracy were found to 
be directly related to the concentration of the parameter and 
essentially independent of the sample matrix. Linear equations to 
describe these relationships are presented in Table 4.

                               References

    1. 40 CFR part 136, appendix B.
    2. ``Determination of Polynuclear Aromatic Hydrocarbons in 
Industrial and Municipal Wastewaters,'' EPA 600/4-82-025, National 
Technical Information Service, PB82-258799, Springfield, Virginia 22161, 
June 1982.
    3. ASTM Annual Book of Standards, Part 31, D3694-78. ``Standard 
Practices for Preparation of Sample Containers and for Preservation of 
Organic Constituents,'' American Society for Testing and Materials, 
Philadelphia.
    4. ``Carcinogens--Working With Carcinogens,'' Department of Health, 
Education, and Welfare, Public Health Service, Center for Disease 
Control, National Institute for Occupational Safety and Health, 
Publication No. 77-206, August 1977.
    5. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR 
part 1910), Occupational Safety and Health Administration, OSHA 2206 
(Revised, January 1976).
    6. ``Safety in Academic Chemistry Laboratories,'' American Chemical 
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
    7. Provost, L.P., and Elder, R.S. ``Interpretation of Percent 
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44 
used in the equation in Section 8.3.3 is two times the value 1.22 
derived in this report.)
    8. ASTM Annual Book of Standards, Part 31, D3370-76. ``Standard 
Practices for Sampling Water,'' American Society for Testing and 
Materials, Philadelphia.
    9. ``Methods 330.4 (Titrimetric, DPD-FAS) and 330.5 
(Spectrophotometric, DPD) for Chlorine, Total Residual,'' Methods for 
Chemical Analysis of Water and Wastes, EPA-600/4-79-020, U.S. 
Environmental Protection Agency, Environmental Monitoring and Support 
Laboratory, Cincinnati, Ohio 45268, March 1979.
    10. Burke, J.A. ``Gas Chromatography for Pesticide Residue Analysis; 
Some Practical Aspects,'' Journal of the Association of Official 
Analytical Chemists, 48, 1037 (1965).
    11. Cole, T., Riggin, R., and Glaser, J. ``Evaluation of Method 
Detection Limits and Analytical Curve for EPA Method 610--PNAs,'' 
International Symposium on Polynuclear Aromatic Hydrocarbons, 5th, 
Battelle's Columbus Laboratories, Columbus, Ohio (1980).
    12. ``EPA Method Study 20, Method 610 (PNA's),'' EPA 600/4-84-063, 
National Technical Information Service, PB84-211614, Springfield, 
Virginia 22161, June 1984.

[[Page 152]]



  Table 1--High Performance Liquid Chromatography Conditions and Method
                            Detection Limits
------------------------------------------------------------------------
                                                                Method
                                        Retention    Column    detection
               Parameter                   time     capacity     limit
                                          (min)      factor    ([mu]g/L)
                                                      (k')         a
------------------------------------------------------------------------
Naphthalene...........................       16.6       12.2       1.8
Acenaphthylene........................       18.5       13.7       2.3
Acenaphthene..........................       20.5       15.2       1.8
Fluorene..............................       21.2       15.8       0.21
Phenanthrene..........................       22.1       16.6       0.64
Anthracene............................       23.4       17.6       0.66
Fluoranthene..........................       24.5       18.5       0.21
Pyrene................................       25.4       19.1       0.27
Benzo(a)anthracene....................       28.5       21.6       0.013
Chrysene..............................       29.3       22.2       0.15
Benzo(b)fluoranthene..................       31.6       24.0       0.018
Benzo(k)fluoranthene..................       32.9       25.1       0.017
Benzo(a)pyrene........................       33.9       25.9       0.023
Dibenzo(a,h)anthracene................       35.7       27.4       0.030
Benzo(ghi)perylene....................       36.3       27.8       0.076
Indeno(1,2,3-cd)pyrene................       37.4       28.7       0.043
------------------------------------------------------------------------
 AAAHPLC column conditions: Reverse phase HC-ODS Sil-X, 5 micron
  particle size, in a 25 cm x 2.6 mm ID stainless steel column.
  Isocratic elution for 5 min. using acetonitrile/water (4+6), then
  linear gradient elution to 100% acetonitrile over 25 min. at 0.5 mL/
  min flow rate. If columns having other internal diameters are used,
  the flow rate should be adjusted to maintain a linear velocity of 2 mm/
  sec.
a The MDL for naphthalene, acenaphthylene, acenaphthene, and fluorene
  were determined using a UV detector. All others were determined using
  a fluorescence detector.


       Table 2--Gas Chromatographic Conditions and Retention Times
------------------------------------------------------------------------
                                                               Retention
                          Parameter                           time (min)
------------------------------------------------------------------------
Naphthalene.................................................         4.5
Acenaphthylene..............................................        10.4
Acenaphthene................................................        10.8
Fluorene....................................................        12.6
Phenanthrene................................................        15.9
Anthracene..................................................        15.9
Fluoranthene................................................        19.8
Pyrene......................................................        20.6
Benzo(a)anthracene..........................................        24.7
Chrysene....................................................        24.7
Benzo(b)fluoranthene........................................        28.0
Benzo(k)fluoranthene........................................        28.0
Benzo(a)pyrene..............................................        29.4
Dibenzo(a,h)anthracene......................................        36.2
Indeno(1,2,3-cd)pyrene......................................        36.2
Benzo(ghi)perylene..........................................        38.6
------------------------------------------------------------------------
GC Column conditions: Chromosorb W-AW-DCMS (100/120 mesh) coated with 3%
  OV-17 packed in a 1.8 x 2 mm ID glass column with nitrogen carrier gas
  at 40 mL/min. flow rate. Column temperature was held at 100  deg.C for
  4 min., then programmed at 8  deg.C/min. to a final hold at 280
  deg.C.


                                   Table 3--QC Acceptance Criteria--Method 610
----------------------------------------------------------------------------------------------------------------
                                                                                        Range for X
                          Parameter                            Test conc.  Limit for s   ([mu]g/L)    Range for
                                                               ([mu]g/L)    ([mu]g/L)                 P, Ps (%)
----------------------------------------------------------------------------------------------------------------
Acenaphthene................................................          100         40.3      D-105.7        D-124
Acenaphthylene..............................................          100         45.1   22.1-112.1        D-139
Anthracene..................................................          100         28.7   11.2-112.3        D-126
Benzo(a)anthracene..........................................           10          4.0     3.1-11.6       12-135
Benzo(a)pyrene..............................................           10          4.0     0.2-11.0        D-128
Benzo(b)fluor-anthene.......................................           10          3.1     1.8-13.8        6-150
Benzo(ghi)perylene..........................................           10          2.3       D-10.7        D-116
Benzo(k)fluo-ranthene.......................................            5          2.5        D-7.0        D-159
Chrysene....................................................           10          4.2       D-17.5        D-199
Dibenzo(a,h)an-thracene.....................................           10          2.0     0.3-10.0        D-110
Fluoranthene................................................           10          3.0     2.7-11.1       14-123
Fluorene....................................................          100         43.0        D-119        D-142
Indeno(1,2,3-cd)pyrene......................................           10          3.0     1.2-10.0        D-116
Naphthalene.................................................          100         40.7   21.5-100.0        D-122
Phenanthrene................................................          100         37.7    8.4-133.7        D-155
Pyrene......................................................           10          3.4     1.4-12.1        D-140
----------------------------------------------------------------------------------------------------------------
s=Standard deviation of four recovery measurements, in [mu]g/L (Section 8.2.4).
X=Average recovery for four recovery measurements, in [mu]g/L (Section 8.2.4).
P, Ps=Percent recovery measured (Section 8.3.2, Section 8.4.2).
D=Detected; result must be greater than zero.
 
Note: These criteria are based directly upon the method performance data in Table 4. Where necessary, the limits
  for recovery have been broadened to assure applicability of the limits to concentrations below those used to
  develop Table 4.


[[Page 153]]


                Table 4--Method Accuracy and Precision as Functions of Concentration--Method 610
----------------------------------------------------------------------------------------------------------------
                                                                   Accuracy, as   Single analyst      Overall
                            Parameter                              recovery, X'   precision, sr'   precision, S'
                                                                     ([mu]g/L)       ([mu]g/L)       ([mu]g/L)
----------------------------------------------------------------------------------------------------------------
Acenaphthene....................................................    0.52C + 0.54    0.39X + 0.76    0.53X + 1.32
Acenaphthylene..................................................    0.69C - 1.89    0.36X + 0.29    0.42X + 0.52
Anthracene......................................................    0.63C - 1.26    0.23X + 1.16    0.41X + 0.45
Benzo(a)anthracene..............................................    0.73C + 0.05    0.28X + 0.04    0.34X + 0.02
Benzo(a)pyrene..................................................    0.56C + 0.01    0.38X - 0.01    0.53X - 0.01
Benzo(b)fluoranthene............................................    0.78C + 0.01    0.21X + 0.01    0.38X - 0.00
Benzo(ghi)perylene..............................................    0.44C + 0.30    0.25X + 0.04    0.58X + 0.10
Benzo(k)fluoranthene............................................    0.59C + 0.00    0.44X - 0.00    0.69X + 0.01
Chrysene........................................................    0.77C - 0.18    0.32X - 0.18    0.66X - 0.22
Dibenzo(a,h)anthracene..........................................    0.41C + 0.11    0.24X + 0.02    0.45X + 0.03
Fluoranthene....................................................    0.68C + 0.07    0.22X + 0.06    0.32X + 0.03
Fluorene........................................................    0.56C - 0.52    0.44X - 1.12    0.63X - 0.65
Indeno(1,2,3-cd)pyrene..........................................    0.54C + 0.06    0.29X + 0.02    0.42X + 0.01
Naphthalene.....................................................    0.57C - 0.70    0.39X - 0.18    0.41X + 0.74
Phenanthrene....................................................    0.72C - 0.95    0.29X + 0.05    0.47X - 0.25
Pyrene..........................................................    0.69C - 0.12    0.25X + 0.14   0.42X - 0.00
----------------------------------------------------------------------------------------------------------------
X'=Expected recovery for one or more measurements of a sample containing a concentration of C, in [mu]g/L.
sr'=Expected single analyst standard deviation of measurements at an average concentration found of X, in [mu]g/
  L.
S'=Expected interlaboratory standard deviation of measurements at an average concentration found of X, in [mu]g/
  L.
C=True value for the concentration, in [mu]g/L.
X=Average recovery found for measurements of samples containing a concentration of C, in [mu]g/L.

[GRAPHIC] [TIFF OMITTED] TC02JY92.031


[[Page 154]]

[GRAPHIC] [TIFF OMITTED] TC02JY92.032


[[Page 155]]

[GRAPHIC] [TIFF OMITTED] TC02JY92.033

                         Method 611--Haloethers

                        1. Scope and Application

    1.1  This method covers the determination of certain haloethers. The 
following parameters can be determined by this method:

------------------------------------------------------------------------
                   Parameter                     STORET No.    CAS No.
------------------------------------------------------------------------
Bis(2-chloroethyl) ether......................        34273     111-44-4
Bis(2-chloroethoxy) methane...................        34278     111-91-1
Bis(2-chloroisopropyl) ether..................        34283     108-60-1
4-Bromophenyl phenyl ether....................        34636     101-55-3
4-Chlorophenyl phenyl either..................        34641    7005-72-3
------------------------------------------------------------------------

    1.2  This is a gas chromatographic (GC) method applicable to the 
determination of the compounds listed above in municipal and industrial 
discharges as provided under 40 CFR 136.1. When this method is used to 
analyze unfamiliar samples for any or all of the compounds above, 
compound identifications should be supported by at least one additional 
qualitative technique. This method describes analytical conditions for a 
second gas chromatographic column that can be used to confirm 
measurements made with the primary column. Method 625 provides gas 
chromatograph/mass spectrometer (GC/MS) conditions appropriate for the 
qualitative and quantitative confirmation of results for all of the 
parameters listed above, using the extract produced by this method.
    1.3  The method detection limit (MDL, defined in Section 
14.1)1 for each parameter is listed in Table 1. The MDL for a 
specific wastewater may differ from those listed, depending upon the 
nature of interferences in the sample matrix.
    1.4  The sample extraction and concentration steps in this method 
are essentially the same as in Methods 606, 608, 609, and 612. Thus, a 
single sample may be extracted to measure the parameters included in the 
scope of each of these methods. When cleanup is required, the 
concentration levels must be high enough to permit selecting aliquots, 
as necessary, to apply appropriate cleanup procedures. The analyst is 
allowed the latitude, under Section 12, to select

[[Page 156]]

chromatographic conditions appropriate for the simultaneous measurement 
of combinations of these parameters.
    1.5  Any modification of this method, beyond those expressly 
permitted, shall be considered as a major modification subject to 
application and approval of alternate test procedures under 40 CFR 136.4 
and 136.5.
    1.6  This method is restricted to use by or under the supervision of 
analysts experienced in the use of a gas chromatograph and in the 
interpretation of gas chromatograms. Each analyst must demonstrate the 
ability to generate acceptable results with this method using the 
procedure described in Section 8.2.

                          2. Summary of Method

    2.1  A measured volume of sample, approximately 1-L, is extracted 
with methylene chloride using a separatory funnel. The methylene 
chloride extract is dried and exchanged to hexane during concentration 
to a volume of 10 mL or less. The extract is separated by gas 
chromatography and the parameters are then measured with a halide 
specific detector.2
    2.2  The method provides a Florisil column cleanup procedure to aid 
in the elimination of interferences that may be encountered.

                            3. Interferences

    3.1  Method interferences may be caused by contaminants in solvents, 
reagents, glassware, and other sample processing hardware that lead to 
discrete artifacts and/or elevated baselines in gas chromatograms. All 
of these materials must be routinely demonstrated to be free from 
interferences under the conditions of the analysis by running laboratory 
reagent blanks as described in Section 8.1.3.
    3.1.1  Glassware must be scrupulously cleaned.3 Clean all 
glassware as soon as possible after use by rinsing with the last solvent 
used in it. Solvent rinsing should be followed be detergent washing with 
hot water, and rinses with tap water and distilled water. The glassware 
should then be drained dry, and heated in a muffle furnace at 400  deg.C 
for 15 to 30 min. Some thermally stable materials, such a PCBs, may not 
be eliminated by this treatment. Solvent rinses with acetone and 
pesticide quality hexane may be substituted for the muffle furnace 
heating. Thorough rinsing with such solvents usually eliminates PCB 
interference. Volumetric ware should not be heated in a muffle furnace. 
After drying and cooling, glassware should be sealed and stored in a 
clean environment to prevent any accumulation of dust or other 
contaminants. Store inverted or capped with aluminum foil.
    3.1.2  The use of high purity reagents and solvents helps to 
minimize interference problems. Purification of solvents by distillation 
in all-glass systems may be required.
    3.2  Matrix interferences may be caused by contaminants that are co-
extracted from the sample. The extent of matrix interferences will vary 
considerably from source to source, depending upon the nature and 
diversity of the industrial complex or municipality being sampled. The 
cleanup procedure in Section 11 can be used to overcome many of these 
interferences, but unique samples may require additional cleanup 
approaches to achieve the MDL listed in Table 1.
    3.3  Dichlorobenzenes are known to coelute with haloethers under 
some gas chromatographic conditions. If these materials are present 
together in a sample, it may be necessary to analyze the extract with 
two different column packings to completely resolve all of the 
compounds.

                                4. Safety

    4.1  The toxicity or carcinogenicity of each reagent used in this 
method has not been precisely defined; however, each chemical compound 
should be treated as a potential health hazard. From this viewpoint, 
exposure to these chemicals must be reduced to the lowest possible level 
by whatever means available. The laboratory is responsible for 
maintaining a current awareness file of OSHA regulations regarding the 
safe handling of the chemicals specified in this method. A reference 
file of material data handling sheets should also be made available to 
all personnel involved in the chemical analysis. Additional references 
to laboratory safety are available and have been identified 
\4\-\6\ for the information of the analyst.

                       5. Apparatus and Materials

    5.1  Sampling equipment, for discrete or composite sampling.
    5.1.1  Grab sample bottle--1-L or 1-qt, amber glass, fitted with a 
screw cap lined with Teflon. Foil may be substituted for Teflon if the 
sample is not corrosive. If amber bottles are not available, protect 
samples from light. The bottle and cap liner must be washed, rinsed with 
acetone or methylene chloride, and dried before use to minimize 
contamination.
    5.1.2  Automatic sampler (optional)--The sampler must incorporate 
glass sample containers for the collection of a minimum of 250 mL of 
sample. Sample containers must be kept refrigerated at 4  deg.C and 
protected from light during compositing. If the sampler uses a 
peristaltic pump, a minimum length of compressible silicone rubber 
tubing may be used. Before use, however, the compressible tubing should 
be thoroughly rinsed with methanol, followed by repeated rinsings with 
distilled water to minimize the potential for contamination of the 
sample. An integrating

[[Page 157]]

flow meter is required to collect flow proportional composites.
    5.2  Glassware (All specifications are suggested. Catalog numbers 
are included for illustration only.):
    5.2.1  Separatory funnel--2-L, with Teflon stopcock.
    5.2.2  Drying column--Chromatographic column, approximately 400 mm 
long x 19 mm ID, with coarse frit filter disc.
    5.2.3  Chromatographic column--400 mm long x 19 mm ID, with Teflon 
stopcock and coarse frit filter disc at bottom (Kontes K-420540-0224 or 
equivalent).
    5.2.4  Concentrator tube, Kuderna-Danish--10-mL, graduated (Kontes 
K-570050-1025 or equivalent). Calibration must be checked at the volumes 
employed in the test. Ground glass stopper is used to prevent 
evaporation of extracts.
    5.2.5  Evaporative flask, Kuderna-Danish--500-mL (Kontes K-570001-
0500 or equivalent). Attach to concentrator tube with springs.
    5.2.6  Snyder column, Kuderna-Danish--Three-ball macro (Kontes K-
503000-0121 or equivalent).
    5.2.7  Vials--10 to 15-mL, amber glass, with Teflon-lined screw cap.
    5.3  Boiling chips--Approximately 10/40 mesh. Heat to 400  deg.C for 
30 min or Soxhlet extract with methylene chloride.
    5.4  Water bath--Heated, with concentric ring cover, capable of 
temperature control (2 deg.C). The bath should be used in a 
hood.
    5.5  Balance--Analytical, capable of accurately weighing 0.0001 g.
    5.6  Gas chromatograph--An analytical system complete with 
temperature programmable gas chromatograph suitable for on-column 
injection and all required accessories including syringes, analytical 
columns, gases, detector, and strip-chart recorder. A data system is 
recommended for measuring peak areas.
    5.6.1  Column 1--1.8 m long x 2 mm ID glass, packed with 3% SP-1000 
on Supelcoport (100/120 mesh) or equivalent. This column was used to 
develop the method performance statements in Section 14. Guidelines for 
the use of alternate column packings are provided in Section 12.1.
    5.6.2  Column 2--1.8 m long x 2 mm ID glass, packed with 2,6-
diphenylene oxide polymer (60/80 mesh), Tenax, or equivalent.
    5.6.3  Detector--Halide specific detector: electrolytic conductivity 
or microcoulometric. These detectors have proven effective in the 
analysis of wastewaters for the parameters listed in the scope (Section 
1.1). The Hall conductivity detector was used to develop the method 
performance statements in Section 14. Guidelines for the use of 
alternate detectors are provided in Section 12.1. Although less 
selective, an electron capture detector is an acceptable alternative.

                               6. Reagents

    6.1  Reagent water--Reagent water is defined as a water in which an 
interferent is not observed at the MDL of the parameters of interest.
    6.2  Sodium thiosulfate--(ACS) Granular.
    6.3  Acetone, hexane, methanol, methylene chloride, petroleum ether 
(boiling range 30-60  deg.C)--Pesticide quality or equivalent.
    6.4  Sodium sulfate--(ACS) Granular, anhydrous. Purify by heating at 
400  deg.C for 4 h in a shallow tray.
    6.5  Florisil--PR Grade (60/100 mesh). Purchase activated at 1250 
deg.F and store in the dark in glass containers with ground glass 
stoppers or foil-lined screw caps. Before use, activate each batch at 
least 16 h at 130  deg.C in a foil-covered glass container and allow to 
cool.
    6.6  Ethyl ether--Nanograde, redistilled in glass if necessary.
    6.6.1  Ethyl ether must be shown to be free of peroxides before it 
is used as indicated by EM Laboratories Quant test strips. (Available 
from Scientific Products Co., Cat. No. P1126-8, and other suppliers.)
    6.6.2  Procedures recommended for removal of peroxides are provided 
with the test strips. After cleanup, 20 mL of ethyl alcohol preservative 
must be added to each liter of ether.
    6.7  Stock standard solutions (1.00 [mu]g/[mu]L)--Stock standard 
solutions can be prepared from pure standard materials or purchased as 
certified solutions.
    6.7.1  Prepare stock standard solutions by accurately weighing about 
0.0100 g of pure material. Dissolve the material in acetone and dilute 
to volume in a 10-mL volumetric flask. Larger volumes can be used at the 
convenience of the analyst. When compound purity is assayed to be 96% or 
greater, the weight can be used without correction to calculate the 
concentration of the stock standard. Commercially prepared stock 
standards can be used at any concentration if they are certified by the 
manufacturer or by an independent source.
    6.7.2  Transfer the stock standard solutions into Teflon-sealed 
screw-cap bottles. Store at 4  deg.C and protect from light. Stock 
standard solutions should be checked frequently for signs of degradation 
or evaporation, especially just prior to preparing calibration standards 
from them.
    6.7.3  Stock standard solutions must be replaced after six months, 
or sooner if comparison with check standards indicates a problem.
    6.8  Quality control check sample concentrate--See Section 8.2.1.

                             7. Calibration

    7.1  Establish gas chromatographic operating conditions equivalent 
to those given in Table 1. The gas chromatographic system

[[Page 158]]

can be calibrated using the external standard technique (Section 7.2) or 
the internal standard technique (Section 7.3).
    7.2  External standard calibration procedure:
    7.2.1  Prepare calibration standards at a minimum of three 
concentration levels for each parameter of interest by adding volumes of 
one or more stock standards to a volumetric flask and diluting to volume 
with hexane. One of the external standards should be at a concentration 
near, but above, the MDL (Table 1) and the other concentrations should 
correspond to the expected range of concentrations found in real samples 
or should define the working range of the detector.
    7.2.2  Using injections of 2 to 5 [mu]L, analyze each calibration 
standard according to Section 12 and tabulate peak height or area 
responses against the mass injected. The results can be used to prepare 
a calibration curve for each compound. Alternatively, if the ratio of 
response to amount injected (calibration factor) is a constant over the 
working range (<10% relative standard deviation, RSD), linearity through 
the origin can be assumed and the average ratio or calibration factor 
can be used in place of a calibration curve.
    7.3  Internal standard calibration procedure--To use this approach, 
the analyst must select one or more internal standards that are similar 
in analytical behavior to the compounds of interest. The analyst must 
further demonstrate that the measurement of the internal standard is not 
affected by method or matrix interferences. Because of these 
limitations, no internal standard can be suggested that is applicable to 
all samples.
    7.3.1  Prepare calibration standards at a minimum of three 
concentration levels for each parameter of interest by adding volumes of 
one or more stock standards to a volumetric flask. To each calibration 
standard, add a known constant amount of one or more internal standards, 
and dilute to volume with hexane. One of the standards should be at a 
concentration near, but above, the MDL and the other concentrations 
should correspond to the expected range of concentrations found in real 
samples or should define the working range of the detector.
    7.3.2  Using injections of 2 to 5 [mu]L, analyze each calibration 
standard according to Section 12 and tabulate peak height or area 
responses against concentration for each compound and internal standard. 
Calculate response factors (RF) for each compound using Equation 1.
[GRAPHIC] [TIFF OMITTED] TC15NO91.116

                                                              Equation 1

where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Cis=Concentration of the internal standard ([mu]g/L).
Cs=Concentration of the parameter to be measured ([mu]g/L).

If the RF value over the working range is a constant (<10% RSD), the RF 
can be assumed to be invariant and the average RF can be used for 
calculations. Alternatively, the results can be used to plot a 
calibration curve of response ratios, As/Ais, vs. 
RF.
    7.4  The working calibration curve, calibration factor, or RF must 
be verified on each working day by the measurement of one or more 
calibration standards. If the response for any parameter varies from the 
predicted response by more than 15%, a new calibration curve 
must be prepared for that compound.
    7.5  The cleanup procedure in Section 11 utilizes Florisil column 
chromatography. Florisil from different batches or sources may vary in 
adsorptive capacity. To standardize the amount of Florisil which is 
used, the use of lauric acid value \7\ is suggested. The referenced 
procedure determines the adsorption from hexane solution of lauric acid 
(mg) per g of Florisil. The amount of Florisil to be used for each 
column is calculated by dividing 110 by this ratio and multiplying by 20 
g.
    7.6  Before using any cleanup procedure, the analyst must process a 
series of calibration standards through the procedure to validate 
elution patterns and the absence of interferences from the reagents.

                           8. Quality Control

    8.1  Each laboratory that uses this method is required to operate a 
formal quality control program. The minimum requirements of this program 
consist of an initial demonstration of laboratory capability and an 
ongoing analysis of spiked samples to evaluate and document data 
quality. The laboratory must maintain records to document the quality of 
data that is generated. Ongoing data quality checks are compared with 
established performance criteria to determine if the results of analyses 
meet the performance characteristics of the method. When results of 
sample spikes indicate atypical method performance, a quality control 
check standard must be analyzed to confirm that the measurements were 
performed in an in-control mode of operation.
    8.1.1  The analyst must make an initial, one-time, demonstration of 
the ability to generate acceptable accuracy and precision with this 
method. This ability is established as described in Section 8.2.

[[Page 159]]

    8.1.2  In recognition of advances that are occurring in 
chromatography, the analyst is permitted certain options (detailed in 
Sections 10.4, 11.1, and 12.1) to improve the separations or lower the 
cost of measurements. Each time such a modification is made to the 
method, the analyst is required to repeat the procedure in Section 8.2.
    8.1.3  Before processing any samples, the analyst must analyze a 
reagent water blank to demonstrate that interferences from the 
analytical system and glassware are under control. Each time a set of 
samples is extracted or reagents are changed, a reagent water blank must 
be processed as a safeguard against laboratory contamination.
    8.1.4  The laboratory must, on an ongoing basis, spike and analyze a 
minimum of 10% of all samples to monitor and evaluate laboratory data 
quality. This procedure is described in Section 8.3.
    8.1.5  The laboratory must, on an ongoing basis, demonstrate through 
the analyses of quality control check standards that the operation of 
the measurement system is in control. This procedure is described in 
Section 8.4. The frequency of the check standard analyses is equivalent 
to 10% of all samples analyzed but may be reduced if spike recoveries 
from samples (Section 8.3) meet all specified quality control criteria.
    8.1.6  The laboratory must maintain performance records to document 
the quality of data that is generated. This procedure is described in 
Section 8.5.
    8.2  To establish the ability to generate acceptable accuracy and 
precision, the analyst must perform the following operations.
    8.2.1  A quality control (QC) check sample concentrate is required 
containing each parameter of interest at a concentration of 100 [mu]g/mL 
in acetone. The QC check sample concentrate must be obtained from the 
U.S. Environmental Protection Agency, Environmental Monitoring and 
Support Laboratory in Cincinnati, Ohio, if available. If not available 
from that source, the QC check sample concentrate must be obtained from 
another external source. If not available from either source above, the 
QC check sample concentrate must be prepared by the laboratory using 
stock standards prepared independently from those used for calibration.
    8.2.2  Using a pipet, prepare QC check samples at a concentration of 
100 [mu]g/L by adding 1.00 mL of QC check sample concentrate to each of 
four 1-L aliquots of reagent water.
    8.2.3  Analyze the well-mixed QC check samples according to the 
method beginning in Section 10.
    8.2.4  Calculate the average recovery (X) in [mu]g/L, and the 
standard deviation of the recovery (s) in [mu]g/L, for each parameter 
using the four results.
    8.2.5  For each parameter compare s and X with the corresponding 
acceptance criteria for precision and accuracy, respectively, found in 
Table 2. If s and X for all parameters of interest meet the acceptance 
criteria, the system performance is acceptable and analysis of actual 
samples can begin. If any individual s exceeds the precision limit or 
any individual X falls outside the range for accuracy, the system 
performance is unacceptable for that parameter. Locate and correct the 
source of the problem and repeat the test for all parameters of interest 
beginning with Section 8.2.2.
    8.3  The laboratory must, on an ongoing basis, spike at least 10% of 
the samples from each sample site being monitored to assess accuracy. 
For laboratories analyzing one to ten samples per month, at least one 
spiked sample per month is required.
    8.3.1.  The concentration of the spike in the sample should be 
determined as follows:
    8.3.1.1  If, as in compliance monitoring, the concentration of a 
specific parameter in the sample is being checked against a regulatory 
concentration limit, the spike should be at that limit or 1 to 5 times 
higher than the background concentration determined in Section 8.3.2, 
whichever concentration would be larger.
    8.3.1.2  If the concentration of a specific parameter in the sample 
is not being checked against a limit specific to that parameter, the 
spike should be at 100 [mu]g/L or 1 to 5 times higher than the 
background concentration determined in Section 8.3.2, whichever 
concentration would be larger.
    8.3.1.3  If it is impractical to determine background levels before 
spiking (e.g., maximum holding times will be exceeded), the spike 
concentration should be (1) the regulatory concentration limit, if any; 
or, if none (2) the larger of either 5 times higher than the expected 
background concentration or 100 [mu]g/L.
    8.3.2  Analyze one sample aliquot to determine the background 
concentration (B) of each parameter. If necessary, prepare a new QC 
check sample concentrate (Section 8.2.1) appropriate for the background 
concentrations in the sample. Spike a second sample aliquot with 1.0 mL 
of the QC check sample concentrate and analyze it to determine the 
concentration after spiking (A) of each parameter. Calculate each 
percent recovery (P) as 100(A-B)%/T, where T is the known true value of 
the spike.
    8.3.3  Compare the percent recovery (P) for each parameter with the 
corresponding QC acceptance criteria found in Table 2. These acceptance 
criteria were calculated to include an allowance for error in 
measurement of both the background and spike concentrations, assuming a 
spike to background ratio of 5:1. This error will be accounted for to 
the extent that the analyst's spike to background ratio approaches 
5:1.\8\ If spiking was performed at a concentration lower than 100 
[mu]g/L, the analyst must use either the QC acceptance criteria in Table 
2, or optional QC

[[Page 160]]

acceptance criteria calculated for the specific spike concentration. To 
calculate optional acceptance criteria for the recovery of a parameter: 
(1) Calculate accuracy (X') using the equation in Table 3, substituting 
the spike concentration (T) for C; (2) calculate overall precision (S') 
using the equation in Table 3, substituting X' for X; (3) calculate the 
range for recovery at the spike concentration as (100 X'/
T)2.44(100 S'/T)%.\8\
    8.3.4  If any individual P falls outside the designated range for 
recovery, that parameter has failed the acceptance criteria. A check 
standard containing each parameter that failed the criteria must be 
analyzed as described in Section 8.4.
    8.4  If any parameter fails the acceptance criteria for recovery in 
Section 8.3, a QC check standard containing each parameter that failed 
must be prepared and analyzed.
    Note: The frequency for the required analysis of a QC check standard 
will depend upon the number of parameters being simultaneously tested, 
the complexity of the sample matrix, and the performance of the 
laboratory.
    8.4.1  Prepare the QC check standard by adding 1.0 m/L of QC check 
sample concentrate (Section 8.2.1 or 8.3.2) to 1 L of reagent water. The 
QC check standard needs only to contain the parameters that failed 
criteria in the test in Section 8.3.
    8.4.2  Analyze the QC check standard to determine the concentration 
measured (A) of each parameter. Calculate each percent recovery 
(Ps) as 100 (A/T)%, where T is the true value of the standard 
concentration.
    8.4.3  Compare the percent recovery (Ps) for each 
parameter with the corresponding QC acceptance criteria found in Table 
2. Only parameters that failed the test in Section 8.3 need to be 
compared with these criteria. If the recovery of any such parameter 
falls outside the designated range, the laboratory performance for that 
parameter is judged to be out of control, and the problem must be 
immediately identified and corrected. The analytical result for that 
parameter in the unspiked sample is suspect and may not be reported for 
regulatory compliance purposes.
    8.5  As part of the QC program for the laboratory, method accuracy 
for wastewater samples must be assessed and records must be maintained. 
After the analysis of five spiked wastewater samples as in Section 8.3, 
calculate the average percent recovery (P) and the standard deviation of 
the percent recovery (sp). Express the accuracy assessment as 
a percent recovery interval from P-2sp to P+2sp. 
If P=90% and sp=10%, for example, the accuracy interval is 
expressed as 70-110%. Update the accuracy assessment for each parameter 
on a regular basis (e.g. after each five to ten new accuracy 
measurements).
    8.6  It is recommended that the laboratory adopt additional quality 
assurance practices for use with this method. The specific practices 
that are most productive depend upon the needs of the laboratory and the 
nature of the samples. Field duplicates may be analyzed to assess the 
precision of the environmental measurements. When doubt exists over the 
identification of a peak on the chromatogram, confirmatory techniques 
such as gas chromatography with a dissimilar column, specific element 
detector, or mass spectrometer must be used. Whenever possible, the 
laboratory should analyze standard reference materials and participate 
in relevant performance evaluation studies.

            9. Sample Collection, Preservation, and Handling

    9.1  Grab samples must be collected in glass containers. 
Conventional sampling practices9 should be followed, except 
that the bottle must not be prerinsed with sample before collection. 
Composite samples should be collected in refrigerated glass containers 
in accordance with the requirements of the program. Automatic sampling 
equipment must be as free as possible of Tygon tubing and other 
potential sources of contamination.
    9.2  All samples must be iced or refrigerated at 4 deg.C 
from the time of collection until extraction. Fill the sample bottles 
and, if residual chlorine is present, add 80 mg of sodium thiosulfate 
per liter of sample and mix well. EPA Methods 330.4 and 330.5 may be 
used for measurement of residual chlorine.10 Field test kits 
are available for this purpose.
    9.3  All samples must be extracted within 7 days of collection and 
completely analyzed within 40 days of extraction.2

                          10. Sample Extraction

    10.1  Mark the water meniscus on the side of the sample bottle for 
later determination of sample volume. Pour the entire sample into a 2-L 
separatory funnel.
    10.2  Add 60 mL methylene chloride to the sample bottle, seal, and 
shake 30 s to rinse the inner surface. Transfer the solvent to the 
separatory funnel and extract the sample by shaking the funnel for 2 min 
with periodic venting to release excess pressure. Allow the organic 
layer to separate from the water phase for a minimum of 10 min. If the 
emulsion interface between layers is more than one-third the volume of 
the solvent layer, the analyst must employ mechanical techniques to 
complete the phase separation. The optimum technique depends upon the 
sample, but may include stirring, filtration of the emulsion through 
glass wool, centrifugation, or other physical methods. Collect the 
methylene chloride extract in a 250-mL Erlenmeyer flask.
    10.3  Add a second 60-mL volume of methylene chloride to the sample 
bottle and repeat the extraction procedure a second time, combining the 
extracts in the Erlenmeyer

[[Page 161]]

flask. Perform a third extraction in the same manner.
    10.4  Assemble a Kuderna-Danish (K-D) concentrator by attaching a 
10-mL concentrator tube to a 500-mL evaporative flask. Other 
concentration devices or techniques may be used in place of the K-D 
concentrator if the requirements of Section 8.2 are met.
    10.5  Pour the combined extract through a solvent-rinsed drying 
column containing about 10 cm of anhydrous sodium sulfate, and collect 
the extract in the K-D concentrator. Rinse the Erlenmeyer flask and 
column with 20 to 30 mL of methylene chloride to complete the 
quantitative transfer.
    10.6  Add one or two clean boiling chips to the evaporative flask 
and attach a three-ball Snyder column. Prewet the Snyder column by 
adding about 1 mL of methylene chloride to the top. Place the K-D 
apparatus on a hot water bath (60 to 65  deg.C) so that the concentrator 
tube is partially immersed in the hot water, and the entire lower 
rounded surface of the flask is bathed with hot vapor. Adjust the 
vertical position of the apparatus and the water temperature as required 
to complete the concentration in 15 to 20 min. At the proper rate of 
distillation the balls of the column will actively chatter but the 
chambers will not flood with condensed solvent. When the apparent volume 
of liquid reaches 1 mL, remove the K-D apparatus and allow it to drain 
and cool for at least 10 min.
    Note: Some of the haloethers are very volatile and significant 
losses will occur in concentration steps if care is not exercised. It is 
important to maintain a constant gentle evaporation rate and not to 
allow the liquid volume to fall below 1 to 2 mL before removing the K-D 
apparatus from the hot water bath.
    10.7  Momentarily remove the Snyder column, add 50 mL of hexane and 
a new boiling chip, and reattach the Snyder column. Raise the 
temperature of the water bath to 85 to 90  deg.C. Concentrate the 
extract as in Section 10.6, except use hexane to prewet the column. The 
elapsed time of concentration should be 5 to 10 min.
    10.8  Remove the Snyder column and rinse the flask and its lower 
joint into the concentrator tube with 1 to 2 mL of hexane. A 5-mL 
syringe is recommended for this operation. Stopper the concentrator tube 
and store refrigerated if further processing will not be performed 
immediately. If the extract will be stored longer than two days, it 
should be transferred to a Teflon-sealed screw-cap vial. If the sample 
extract requires no further cleanup, proceed with gas chromatographic 
analysis (Section 12). If the sample requires further cleanup, proceed 
to Section 11.
    10.9  Determine the original sample volume by refilling the sample 
bottle to the mark and transferring the liquid to a 1000-mL graduated 
cylinder. Record the sample volume to the nearest 5 mL.

                       11. Cleanup and Separation

    11.1  Cleanup procedures may not be necessary for a relatively clean 
sample matrix. If particular circumstances demand the use of a cleanup 
procedure, the analyst may use the procedure below or any other 
appropriate procedure. However, the analyst first must demonstrate that 
the requirements of Section 8.2 can be met using the method as revised 
to incorporate the cleanup procedure.
    11.2  Florisil column cleanup for haloethers:
    11.2.1  Adjust the sample extract volume to 10 mL.
    11.2.2  Place a weight of Florisil (nominally 20 g) predetermined by 
calibration (Section 7.5), into a chromatographic column. Tap the column 
to settle the Florisil and add 1 to 2 cm of anhydrous sodium sulfate to 
the top.
    11.2.3  Preelute the column with 50 to 60 mL of petroleum ether. 
Discard the eluate and just prior to exposure of the sodium sulfate 
layer to the air, quantitatively transfer the sample extract onto the 
column by decantation and subsequent petroleum ether washings. Discard 
the eluate. Just prior to exposure of the sodium sulfate layer to the 
air, begin eluting the column with 300 mL of ethyl ether/petroleum ether 
(6+94) (V/V). Adjust the elution rate to approximately 5 mL/min and 
collect the eluate in a 500-mL K-D flask equipped with a 10-mL 
concentrator tube. This fraction should contain all of the haloethers.
    11.2.4  Concentrate the fraction as in Section 10.6, except use 
hexane to prewet the column. When the apparatus is cool, remove the 
Snyder column and rinse the flask and its lower joint into the 
concentrator tube with hexane. Adjust the volume of the cleaned up 
extract to 10 mL with hexane and analyze by gas chromatography (Section 
12).

                         12. Gas Chromatography

    12.1  Table 1 summarizes the recommended operating conditions for 
the gas chromatograph. Included in this table are retention times and 
MDL that can be achieved under these conditions. Examples of the 
separations achieved by Columns 1 and 2 are shown in Figures 1 and 2, 
respectively. Other packed or capillary (open-tubular) columns, 
chromatographic conditions, or detectors may be used if the requirements 
of Section 8.2 are met.
    12.2  Calibrate the system daily as described in Section 7.
    12.3  If the internal standard calibration procedure is being used, 
the internal standard must be added to the sample extract and mixed 
thoroughly immediately before injection into the gas chromatrograph.

[[Page 162]]

    12.4  Inject 2 to 5 [mu]L of the sample extract or standard into the 
gas chromatograph using the solvent-flush technique.11 
Smaller (1.0 [mu]L) volumes may be injected if automatic devices are 
employed. Record the volume injected to the nearest 0.05 [mu]L, the 
total extract volume, and the resulting peak size in area or peak height 
units.
    12.5  Identify the parameters in the sample by comparing the 
retention times of the peaks in the sample chromatogram with those of 
the peaks in standard chromatograms. The width of the retention time 
window used to make identifications should be based upon measurements of 
actual retention time variations of standards over the course of a day. 
Three times the standard deviation of a retention time for a compound 
can be used to calculate a suggested window size; however, the 
experience of the analyst should weight heavily in the interpretation of 
chromatograms.
    12.6  If the response for a peak exceeds the working range of the 
system, dilute the extract and reanalyze.
    12.7  If the measurement of the peak response is prevented by the 
presence of interferences, further cleanup is required.

                            13. Calculations

    13.1  Determine the concentration of individual compounds in the 
sample.
    13.1.1  If the external standard calibration procedure is used, 
calculate the amount of material injected from the peak response using 
the calibration curve or calibration factor determined in Section 7.2.2. 
The concentration in the sample can be calculated from Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.117

                                                              Equation 2

where:
A=Amount of material injected (ng).
Vi=Volume of extract injected ([mu]L).
Vt=Volume of total extract ([mu]L).
Vs=Volume of water extracted (mL).

    13.1.2  If the internal standard calibration procedure is used, 
calculate the concentration in the sample using the response factor (RF) 
determined in Section 7.3.2 and Equation 3.
[GRAPHIC] [TIFF OMITTED] TC15NO91.118

                                                              Equation 3

where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Is=Amount of internal standard added to each extract ([mu]g).
Vo=Volume of water extracted (L).

    13.2  Report results in [mu]g/L without correction for recovery 
data. All QC data obtained should be reported with the sample results.

                         14. Method Performance

    14.1  The method detection limit (MDL) is defined as the minimum 
concentration of a substance that can be measured and reported with 99% 
confidence that the value is above zero.1 The MDL 
concentrations listed in Table 1 were obtained using reagent 
water.12 Similar results were achieved using representative 
wastewaters. The MDL actually achieved in a given analysis will vary 
depending on instrument sensitivity and matrix effects.
    14.2  This method has been tested for linearity of spike recovery 
from reagent water and has been demonstrated to be applicable over the 
concentration range from 4 x MDL to 1000 x MDL.12
    14.3  This method was tested by 20 laboratories using reagent water, 
drinking water, surface water, and three industrial wastewaters spiked 
at six concentrations over the range 1.0 to 626 [mu]/L.12 
Single operator precision, overall precision, and method accuracy were 
found to be directly related to the concentration of the parameter and 
essentially independent of the sample matrix. Linear equations to 
describe these relationships are presented in Table 3.

                               References

    1. 40 CFR part 136, appendix B.
    2. ``Determination of Haloethers in Industrial and Municipal 
Wastewaters,'' EPA 600/4-81-062, National Technical Information Service, 
PB81-232290, Springfield, Virginia 22161, July 1981.
    3. ASTM Annual Book of Standards, Part 31, D3694-78. ``Standard 
Practices for Preparation of Sample Containers and for Preservation of 
Organic Constitutents,'' American Society for Testing and Materials, 
Philadelphia.
    4. ``Carcinogens--Working Carcinogens, '' Department of Health, 
Education, and Welfare, Public Health Services, Center for Disease 
Control, National Institute for Occupational Safety and Health, 
Publication No. 77-206, August 1977.
    5. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR 
part 1910), Occupational Safety and Health Administration, OSHA 2206 
(Revised, January 1976).
    6. ``Safety in Academic Chemistry Laboratories,'' American Chemical 
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
    7. Mills., P.A. ``Variation of Florisil Activity: Simple Method for 
Measuring Absorbent Capacity and Its Use in Standardizing

[[Page 163]]

Florisil Columns,'' Journal of the Association of Official Analytical 
Chemists, 51, 29 (1968).
    8. Provost, L.P., and Elder, R.S. ``Interpretation of Percent 
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44 
used in the equation in Section 8.3.3 is two times the value 1.22 
derived in this report.)
    9. ASTM Annual Book of Standards, Part 31, D3370-76. ``Standard 
Practices for Sampling Water,'' American Society for Testing and 
Materials, Philadelphia.
    10. ``Methods 330.4 (Titrimetric, DPD-FAS) and 330.5 
(Spectrophotometric, DPD) for Chlorine, Total Residual,'' Methods for 
Chemical Analysis of Water and Wastes, EPA-600/4-79-020, U.S. 
Environmental Protection Agency, Environmental Monitoring and Support 
Laboratory, Cincinnati, Ohio 45268, March 1979.
    11. Burke, J.A. ``Gas Chromatography for Pesticide Residue Analysis; 
Some Practical Aspects,'' Journal of the Association of Official 
Analytical Chemists, 48, 1037 (1965).
    12. ``EPA Method Study 21, Method 611, Haloethers,'' EPA 600/4-84-
052, National Technical Information Service, PB84-205939, Springfield, 
Virginia 22161, June 1984.

    Table 1--Chromatographic Conditions and Methods Detection Limits
------------------------------------------------------------------------
                                         Retention time (min)    Method
                                        ---------------------- detection
               Parameters                                        limit
                                          Column 1   Column 2   ([mu]/L)
------------------------------------------------------------------------
Bis(2-chloroisopropyl) ether...........        8.4        9.7        0.8
Bis(2-chloroethyl) ether...............        9.3        9.1        0.3
Bis(2-chloroethoxy) methane............       13.1       10.0        0.5
4-Chlorophenyl ether...................       19.4       15.0        3.9
4-Bromophenyl phenyl ether.............       21.2       16.2        2.3
------------------------------------------------------------------------
 AColumn 1 conditions: Supelcoport (100/120 mesh) coated with 3% SP-1000
  packed in a 1.8 m long x 2 mm ID glass column with helium carrier gas
  at 40 mL/min. flow rate. Column temperature held at 60  deg.C for 2
  min. after injection then programmed at 8  deg.C/min. to 230  deg.C
  and held for 4 min. Under these conditions the retention time for
  Aldrin is 22.6 min.
 AColumn 2 conditions: Tenax-GC (60/80 mesh) packed in a 1.8 m long x
  2mm ID glass column with helium carrier gas at 40 mL/min. flow rate.
  Column temperature held at 150  deg.C for 4 min. after injection then
  programmed at 16  deg.C/min. to 310  deg.C. Under these conditions the
  retention time for Aldrin is 18.4 min.


                                   Table 2--QC Acceptance Criteria--Method 611
----------------------------------------------------------------------------------------------------------------
                                                                                        Range for X   Range for
                         Parameter                            Test conc.   Limit for s   ([mu]g/L)      P, Ps
                                                              ([mu]g/L)     ([mu]g/L)                  percent
----------------------------------------------------------------------------------------------------------------
Bis (2-chloroethyl)ether...................................          100          26.3   26.3-136.8       11-152
Bis (2-chloroethoxy)methane................................          100          25.7   27.3-115.0       12-128
Bis (2-chloroisopropyl)ether...............................          100          32.7   26.4-147.0        9-165
4-Bromophenyl phenyl ether.................................          100          39.3   7.6 -167.5        D-189
4-Chlorophenyl phenyl ether................................          100          30.7   15.4-152.5        D-170
----------------------------------------------------------------------------------------------------------------
s=Standard deviation of four recovery measurements, in [mu]g/L (Section 8.2.4).
X=Average recovery for four recovery measurements, in [mu]g/L (Section 8.2.4).
P, Ps=Percent recovery measured (Section 8.3.2, Section 8.4.2).
D=Detected; result must be greater than zero.
 
Note: These criteria are based directly upon the method performance data in Table 3. Where necessary, the limits
  for recovery have been broadened to assure applicability of the limits to concentrations below those used to
  develop Table 3.


                Table 3--Method Accuracy and Precision as Functions of Concentration--Method 611
----------------------------------------------------------------------------------------------------------------
                                                                   Accuracy, as   Single analyst      Overall
                            Parameter                              recovery, X'   precision, sr'   precision, S'
                                                                     ([mu]g/L)       ([mu]g/L)       ([mu]g/L)
----------------------------------------------------------------------------------------------------------------
Bis(2-chloroethyl) ether........................................      0.81C+0.54      0.19X+0.28      0.35X+0,36
Bis(2-chloroethoxy) methane.....................................      0.71C+0.13      0.20X+0.15      0.33X+0.11
Bis(2-chloroisopropyl) ether....................................      0.85C+1.67      0.20X+1.05      0.36X+0.79
4-Bromophenyl phenyl ether......................................      0.85C+2.55      0.25X+0.21      0.47X+0.37
4-Chlorophenyl phenyl ether.....................................      0.82C+1.97      0.18X+2.13      0.41X+0.55
----------------------------------------------------------------------------------------------------------------
X' = Expected recovery for one or more measuremelts of a sample containing a concentration of C, in [mu]g/L.
sr' = Expected single analyst standard deviation of measurements at an average concentration found of X, in
  [mu]g/L.
S' = Expected interlaboratory standard deviation of measurements at an average concentration found of X, in
  [mu]g/L.
C =True value for the concentration, in [mu]g/L.
X = Average recovery found for measurements of samples containing a concentration of C, in [mu]g/L.


[[Page 164]]

[GRAPHIC] [TIFF OMITTED] TC02JY92.034


[[Page 165]]

[GRAPHIC] [TIFF OMITTED] TC02JY92.035

                  Method 612--Chlorinated Hydrocarbons

                        1. Scope and Application

    1.1  This method covers the determination of certain chlorinated 
hydrocarbons. The following parameters can be determined by this method:

------------------------------------------------------------------------
                                                    STORET
                    Parameter                         No.      CAS No.
------------------------------------------------------------------------
2-Chloronaphthalene..............................     34581      91-58-7
1,2-Dichlorobenzene..............................     34536      95-50-1
1,3-Dichlorobenzene..............................     34566     541-73-1
1,4-Dichlorobenzene..............................     34571     106-46-7
Hexachlorobenzene................................     39700     118-74-1
Hexachlorobutadiene..............................     34391      87-68-3
Hexachlorocyclopentadiene........................     34386      77-47-4
Hexachloroethane.................................     34396      67-72-1

[[Page 166]]

 
1,2,4-Trichlorobenzene...........................     34551     120-82-1
------------------------------------------------------------------------

    1.2  This is a gas chromatographic (GC) method applicable to the 
determination of the compounds listed above in municipal and industrial 
discharges as provided under 40 CFR 136.1. When this method is used to 
analyze unfamiliar samples for any or all of the compounds above, 
compound identifications should be supported by at least one additional 
qualitative technique. This method describes a second gas 
chromatographic column that can be used to confirm measurements made 
with the primary column. Method 625 provides gas chromatograph/mass 
spectrometer (GC/MS) conditions appropriate for the qualitative and 
quantitative confirmation of results for all of the parameters listed 
above, using the extract produced by this method.
    1.3  The method detection limit (MDL, defined in Section 14.1)\1\ 
for each parameter is listed in Table 1. The MDL for a specific 
wastewater may differ from those listed, depending upon the nature of 
interferences in the sample matrix.
    1.4  The sample extraction and concentration steps in this method 
are essentially the same as in Methods 606, 608, 609, and 611. Thus, a 
single sample may be extracted to measure the parameters included in the 
scope of each of these methods. When cleanup is required, the 
concentration levels must be high enough to permit selecting aliquots, 
as necessary, to apply appropriate cleanup procedures. The analyst is 
allowed the latitude, under Section 12, to select chromatographic 
conditions appropriate for the simultaneous measurement of combinations 
of these parameters.
    1.5  Any modification of this method, beyond those expressly 
permitted, shall be considered as a major modification subject to 
application and approval of alternate test procedures under 40 CFR 136.4 
and 136.5.
    1.6  This method is restricted to use by or under the supervision of 
analysts experienced in the use of a gas chromatograph and in the 
interpretation of gas chromatograms. Each analyst must demonstrate the 
ability to generate acceptable results with this method using the 
procedure described in Section 8.2.

                          2. Summary of Method

    2.1  A measured volume of sample, approximately 1-L, is extracted 
with methylene chloride using a separatory funnel. The methylene 
chloride extract is dried and exchanged to hexane during concentration 
to a volume of 10 mL or less. The extract is separated by gas 
chromatography and the parameters are then measured with an electron 
capture detector. \2\
    2.2  The method provides a Florisil column cleanup procedure to aid 
in the elimination of interferences that may be encountered.

                            3. Interferences

    3.1  Method interferences may be caused by contaminants in solvents, 
reagents, glassware, and other sample processing hardware that lead to 
discrete artifacts and/or elevated baselines in gas chromatograms. All 
of these materials must be routinely demonstrated to be free from 
interferences under the conditions of the analysis by running laboratory 
reagent blanks as described in Section 8.1.3.
    3.1.1  Glassware must be scrupulously cleaned. \3\ Clean all 
glassware as soon as possible after use by rinsing with the last solvent 
used in it. Solvent rinsing should be followed by detergent washing with 
hot water, and rinses with tap water and distilled water. The glassware 
should then be drained dry, and heated in a muffle furnace at 400  deg.C 
for 15 to 30 min. Some thermally stable materials, such as PCBs, may not 
be eliminated by this treatment. Solvent rinses with acetone and 
pesticide quality hexane may be substituted for the muffle furnace 
heating. Thorough rinsing with such solvents usually eliminates PCB 
interference. Volumetric ware should not be heated in a muffle furnace. 
After drying and cooling, glassware should be sealed and stored in a 
clean environment to prevent any accumulation of dust or other 
contaminants. Store inverted or capped with aluminum foil.
    3.1.2  The use of high purity reagents and solvents helps to 
minimize interference problems. Purification of solvents by distillation 
in all-glass systems may be required.
    3.2  Matrix interferences may be caused by contaminants that are co-
extracted from the sample. The extent of matrix interferences will vary 
considerably from source to source, depending upon the nature and 
diversity of the industrial complex or municipality being sampled. The 
cleanup procedure in Section 11 can be used to overcome many of these 
interferences, but unique samples may require additional cleanup 
approaches to achieve the MDL listed in Table 1.

                                4. Safety

    4.1  The toxicity or carcinogenicity of each reagent used in this 
method has not been precisely defined; however, each chemical compound 
should be treated as a potential health hazard. From this viewpoint, 
exposure to these chemicals must be reduced to the lowest possible level 
by whatever means available. The laboratory is responsible for 
maintaining a current awareness file of OSHA regulations regarding the 
safe handling of the chemicals specified in this method. A reference 
file of material data handling sheets should also be made available to 
all

[[Page 167]]

personnel involved in the chemical analysis. Additional references to 
laboratory safety are available and have been identified 4-6 
for the information of the analyst.

                       5. Apparatus and Materials

    5.1  Sampling equipment, for discrete or composite sampling.
    5.1.1  Grab sample bottle--1cL or 1-qt, amber glass, fitted with a 
screw cap lined with Teflon. Foil may be substituted for Teflon if the 
sample is not corrosive. If amber bottles are not available, protect 
samples from light. The bottle and cap liner must be washed, rinsed with 
acetone or methylene chloride, and dried before use to minimize 
contamination.
    5.1.2  Automatic sampler (optional)--The sampler must incorporate 
glass sample containers for the collection of a minimum of 250 mL of 
sample. Sample containers must be kept refrigerated at 4  deg.C and 
protected from light during compositing. If the sampler uses a 
peristaltic pump, a minimum length of compressible silicone rubber 
tubing may be used. Before use, however, the compressible tubing should 
be thoroughly rinsed with methanol, followed by repeated rinsings with 
distilled water to minimize the potential for contamination of the 
sample. An integrating flow meter is required to collect flow 
proportional composites.
    5.2  Glassware (All specifications are suggested. Catalog numbers 
are included for illustration only.):
    5.2.1  Separatory funnel--2-L, with Teflon stopcock.
    5.2.2  Drying column--Chromatographic column, approximately 400 mm 
long x 19 mm ID, with coarse frit filter disc.
    5.2.3  Chromatographic column--300 long x 10 mm ID, with Teflon 
stopcock and coarse frit filter disc at bottom.
    5.2.4  Concentrator tube, Kuderna-Danish--10-mL, graduated (Kontes 
K-570050-1025 or equivalent). Calibration must be checked at the volumes 
employed in the test. Ground glass stopper is used to prevent 
evaporation of extracts.
    5.2.5  Evaporative flask, Kuderna-Danish--500-mL (Kontes K-570001-
0500 or equivalent). Attach to concentrator tube with springs.
    5.2.6  Snyder column, Kuderna-Danish--Three-ball macro (Kontes K-
503000-0121 or equivalent).
    5.2.7  Vials--10 to 15-mL, amber glass, with Teflon-lined screw cap.
    5.3  Boiling chips--Approximately 10/40 mesh. Heat to 400  deg.C for 
30 min or Soxhlet extract with methylene chloride.
    5.4  Water bath--Heated, with concentric ring cover, capable of 
temperature control (2  deg.C). The bath should be used in a 
hood.
    5.5  Balance--Analytical, capable of accurately weighing 0.0001 g.
    5.6  Gas chromatograph--An analytical system complete with gas 
chromatograph suitable for on-column injection and all required 
accessories including syringes, analytical columns, gases, detector, and 
strip-chart recorder. A data system is recommended for measuring peak 
areas.
    5.6.1  Column 1--1.8 m long x 2 mm ID glass, packed with 1% SP-1000 
on Supelcoport (100/120 mesh) or equivalent. Guidelines for the use of 
alternate column packings are provide in Section 12.1.
    5.6.2  Column 2--1.8 m long x2 mm ID glass, packed with 1.5% OV-1/
2.4% OV-225 on Supelcoport (80/100 mesh) or equivalent. This column was 
used to develop the method performance statements in Section 14.
    5.6.3  Detector-- Electron capture detector. This detector has 
proven effective in the analysis of wastewaters for the parameters 
listed in the scope (Section 1.1), and was used to develop the method 
performance statements in Section 14. Guidelines for the use of 
alternate detectors are provided in Section 12.1.

                               6. Reagents

    6.1  Reagent water-- Reagent water is defined as a water in which an 
interferent is not observed at the MDL of the parameters of interest.
    6.2  Acetone, hexane, isooctane, methanol, methylene chloride, 
petroleum ether (boiling range 30 to 60  deg.C)--Pesticide quality or 
equivalent.
    6.3  Sodium sulfate--(ACS) Granular, anhydrous. Purify heating at 
400  deg.C for 4 h in a shallow tray.
    6.4  Florisil--PR grade (60/100 mesh). Purchase activated at 1250 
deg.F and store in the dark in glass containers with ground glass 
stoppers or foil-lined screw caps. Before use, activate each batch at 
least 16 h at 130  deg.C in a foil-covered glass container and allow to 
cool.
    6.5  Stock standard solution (1.00 [mu]g/[mu]L)--Stock standard 
solutions can be prepared from pure standard materials or purchased as 
certified solutions.
    6.5.1  Prepare stock standard solutions by accurately weighing about 
0.0100 g of pure material. Dissolve the material in isooctane and dilute 
to volume in a 120-mL volumetric flask. Larger volumes can be used at 
the convenience of the analyst. When compound purity is assayed to be 
96% or greater, the weight can be used without correction to calculate 
the concentration of the stock standard. Commercially prepared stock 
standards can be used at any concentration if they are certified by the 
manufacturer or by an independent source.
    6.5.2  Transfer the stock standard solutions into Teflon-sealed 
screw-cap bottles. Store at 4  deg.C and protect from light. 
Stock standard solutions should be checked frequently for signs of 
degradation or evaporation, especially just prior to preparing 
calibration standards from them.

[[Page 168]]

    6.5.3  Stock standard solutions must be replaced after six months, 
or sooner if comparision with check standards indicates a problem.
    6.6  Quality control check sample concentrate--See Section 8.2.1.

                             7. Calibration

    7.1  Establish gas chromatographic operating conditions equivalent 
to those given in Table 1. The gas chromatographic system can be 
calibrated using the external standard technique (Section 7.2) or the 
internal standard technique (Section 7.3).
    7.2  External standard calibration procedure:
    7.2.1  Prepare calibration standards at a minimum of three 
concentration levels for each parameter of interest by adding volumes of 
one or more stock standards to a volumetric flask and diluting to volume 
with isooctane. One of the external standards should be at a 
concentration near, but above, the MDL (Table 1) and the other 
concentrations should correspond to the expected range of concentrations 
found in real samples or should define the working range of the 
detector.
    7.2.2  Using injections of 2 to 5 [mu]L, analyze each calibration 
standard according to Section 12 and tabulate peak height or area 
responses against the mass injected. The results can be used to prepare 
a calibration curve for each compound. Alternatively, if the ratio of 
response to amount injected (calibration factor) is a constant over the 
working range (<10% relative standard deviation, RSD), linearity through 
the origin can be assumed and the average ratio or calibration factor 
can be used in place of a calibration curve.
    7.3  Internal standard calibration procedure--To use this approach, 
the analyst must select one or more internal standards that are similar 
in analytical behavior to the compounds of interest. The analyst must 
further demonstrate that the measurement of the internal standard is not 
affected by method or matrix interferences. Because of these 
limitations, no internal standard can be suggested that is applicable to 
all samples.
    7.3.1  Prepare calibration standards at a minimum of three 
concentration levels for each parameter of interest by adding volumes of 
one or more stock standards to a volumetric flask. To each calibration 
standard, add a known constant amount of one or more internal standards, 
and dilute to volume with isooctane. One of the standards should be at a 
concentration near, but above, the MDL and the other concentrations 
should correspond to the expected range of concentrations found in real 
samples or should define the working range of the detector.
    7.3.2  Using injections of 2 to 5 [mu]L, analyze each calibration 
standard according to Section 12 and tabulate peak height or area 
responses against concentration for each compound and internal standard. 
Calculate response factors (RF) for each compound using Equation 1.
[GRAPHIC] [TIFF OMITTED] TC15NO91.119

                                                              Equation 1

where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Cis=Concentration of the internal standard ([mu]g/L).
Cs=Concentration of the parameter to be measured ([mu]g/L).

If the RF value over the working range is a constant (<10% RSD), the RF 
can be assumed to be invariant and the average RF can be used for 
calculations. Alternatively, the results can be used to plot a 
calibration curve of response ratios, As/Ais, vs. 
RF.
    7.4  The working calibration curve, calibration factor, or RF must 
be verified on each working day by the measurement of one or more 
calibration standards. If the response for any parameter varies from the 
predicted response by more than 15%, a new calibration curve 
must be prepared for that compound.
    7.5  Before using any cleanup procedure, the analyst must process a 
series of calibration standards through the procedure to validate 
elution patterns and the absence of interferences from the reagents.

                           8. Quality Control

    8.1  Each laboratory that uses this method is required to operate a 
formal quality control program. The minimum requirements of this program 
consist of an initial demonstration of laboratory capability and an 
ongoing analysis of spiked samples to evaluate and document data 
quality. The laboratory must maintain records to document the quality of 
data that is generated. Ongoing data quality checks are compared with 
established performance criteria to determine if the results of analyses 
meet the performance characteristics of the method. When the results of 
sample spikes indicate atypical method performance, a quality control 
check standard must be analyzed to confirm that the measurements were 
performed in an in-control mode of operation.
    8.1.1  The analyst must make an initial, one-time, demonstration of 
the ability to generate acceptable accuracy and precision with this 
method. This ability is established as described in Section 8.2.

[[Page 169]]

    8.1.2  In recognition of advances that are occurring in 
chromatography, the analyst is permitted certain options (detailed in 
Sections 10.4, 11.1, and 12.1) to improve the separations or lower the 
cost of measurements. Each time such modification is made to the method, 
the analyst is required to repeat the procedure in Section 8.2.
    8.1.3  Before processing any samples, the analyst must analyze a 
reagent water blank to demonstrate that interferences from the 
analytical system and glassware are under control. Each time a set of 
samples is extracted or reagents are changed, a reagent water blank must 
be processed as a safeguard against laboratory contamination.
    8.1.4  The laboratory must, on an ongoing basis, spike and analyze a 
minimum of 10% of all samples to monitor and evaluate laboratory data 
quality. This procedure is described in Section 8.3.
    8.1.5  The laboratory must, on an ongoing basis, demonstrate through 
the analyses of quality control check standards that the operation of 
the measurement system is in control. This procedure is described in 
Section 8.4. The frequency of the check standard analyses is equivalent 
to 10% of all samples analyzed but may be reduced if spike recoveries 
from samples (Section 8.3) meet all specified quality control criteria.
    8.1.6  The laboratory must maintain performance records to document 
the quality of data that is generated. This procedure is described in 
Section 8.5.
    8.2  To establish the ability to generate acceptable accuracy and 
precision, the analyst must perform the following operations.
    8.2.1  A quality control (QC) check sample concentrate is required 
containing each parameter of interest at the following concentrations in 
acetone: Hexachloro-substituted parameters, 10 [mu]g/mL; any other 
chlorinated hydrocarbon, 100 [mu]g/mL. The QC check sample concentrate 
must be obtained from the U.S. Environmental Protection Agency, 
Environmental Monitoring and Support Laboratory in Cincinnati, Ohio, if 
available. If not available from that source, the QC check sample 
concentrate must be obtained from another external source. If not 
available from either source above, the QC check sample concentrate must 
be prepared by the laboratory using stock standards prepared 
independently from those used for calibration.
    8.2.2  Using a pipet, prepare QC check samples at the test 
concentrations shown in Table 2 by adding 1.00 mL of QC check sample 
concentrate to each of four 1-L aliquots of reagent water.
    8.2.3  Analyze the well-mixed QC check samples according to the 
method beginning in Section 10.
    8.2.4  Calculate the average recovery (X) in [mu]g/L, and the 
standard deviation of the recovery (s) in [mu]g/L, for each parameter 
using the four results.
    8.2.5  For each parameter compare s and X with the corresponding 
acceptance criteria for precision and accuracy, respectively, found in 
Table 2. If s and X for all parameters of interest meet the acceptance 
criteria, the system performance is acceptable and analysis of actual 
samples can begin. If any individual s exceeds the precision limit or 
any individual X falls outside the range for accuracy, the system 
performance is unacceptable for that parameter.
    Note: The large number of parameters in Table 2 presents a 
substantial probability that one or more will fail at least one of the 
acceptance criteria when all parameters are analyzed.
    8.2.6  When one or more of the parameters tested fail at least one 
of the acceptance criteria, the analyst must proceed according to 
Section 8.2.6.1 or 8.2.6.2.
    8.2.6.1  Locate and correct the source of the problem and repeat the 
test for all parameters of interest beginning with Section 8.2.2.
    8.2.6.2  Beginning with Section 8.2.2, repeat the test only for 
those parameters that failed to meet criteria. Repeated failure, 
however, will confirm a general problem with the measurement system. If 
this occurs, locate and correct the source of the problem and repeat the 
test for all compounds of interest beginning with Section 8.2.2.
    8.3  The laboratory must, on an ongoing basis, spike at least 10% of 
the samples from each sample site being monitored to assess accuracy. 
For laboratories analyzing one to ten samples per month, at least one 
spike sample per month is required.
    8.3.1  The concentration of the spike in the sample should be 
determined as follows:
    8.3.1.1  If, as in compliance monitoring, the concentration of a 
specific parameter in the sample is being checked against a regulatory 
concentration limit, the spike should be at that limit or 1 to 5 times 
higher than the background concentration determined in Section 8.3.2, 
whichever concentration would be larger.
    8.3.1.2  If the concentration of a specific parameter in the sample 
is not being checked against a limit specific to that parameter, the 
spike should be at the test concentration in Section 8.2.2 or 1 to 5 
times higher than the background concentration determined in Section 
8.3.2, whichever concentration would be larger.
    8.3.1.3  If it is impractical to determine background levels before 
spiking (e.g., maximum holding times will be exceeded), the spike 
concentration should be (1) the regulatory concentration limit, if any; 
or, if none by (2) the larger of either 5 times higher than the expected 
background concentration or the test concentration in Section 8.2.2.

[[Page 170]]

    8.3.2 Analyze one sample aliquot to determine the background 
concentration (B) of each parameter. In necessary, prepare a new QC 
check sample concentrate (Section 8.2.1) appropriate for the background 
concentrations in the sample. Spike a second sample aliquot with 1.0 mL 
of the QC check sample concentrate and analyze it to determine the 
concentration after spiking (A) of each parameter. Calculate each 
percent recovery (P) as 100 (A-B)%/T, where T is the known true value of 
the spike.
    8.3.3 Compare the percent recovery (P) for each parameter with the 
corresponding QC acceptance criteria found in Table 2. These acceptance 
criteria were calculated to include an allowance for error in 
measurement of both the background and spike concentrations, assuming a 
spike to background ratio of 5:1. This error will be accounted for to 
the extent that the analyst's spike to background ratio approaches 5:1. 
\7\ If spiking was performed at a concentration lower than the test 
concentration in Section 8.2.2, the analyst must use either the QC 
acceptance criteria in Table 2, or optional QC acceptance criteria 
calculated for the specific spike concentration. To calculate optional 
acceptance criteria for the recovery of a parameter: (1) Calculate 
accuracy (X') using the equation in Table 3, substituting the spike 
concentration (T) for C; (2) calculate overall precision (S') using the 
equation in Table 3, substituting X' for X; (3) calculate the range for 
recovery at the spike concentration as (100 X'/T)  2.44 (100 
S'/T)%. \7\
    8.3.4 If any individual P falls outside the designated range for 
recovery, that parameter has failed the acceptance criteria. A check 
standard containing each parameter that failed the criteria must be 
analyzed as described in Section 8.4.
    8.4. If any parameter fails the acceptance criteria for recovery in 
Section 8.3, a QC check standard containing each parameter that failed 
must be prepared and analyzed.
    Note: The frequency for the required analysis of a QC check standard 
will depend upon the number of parameters being simultaneously tested, 
the complexity of the sample matrix, and the performance of the 
laboratory.
    8.4.1 Prepare the QC check standard by adding 1.0 mL of QC check 
sample concentrate (Sections 8.2.1 or 8.3.2) to 1 L of reagent water. 
The QC check standard needs only to contain the parameters that failed 
criteria in the test in Section 8.3.
    8.4.2  Analyze the QC check standard to determine the concentration 
measured (A) of each parameter. Calculate each percent recovery 
(Ps) as 100 (A/T)%, where T is the true value of the standard 
concentration.
    8.4.3  Compare the percent recovery (Ps) for each 
parameter with the corresponding QC acceptance criteria found in Table 
2. Only parameters that failed the test in Section 8.3 need to be 
compared with these criteria. If the recovery of any such parameter 
falls outside the designated range, the laboratory performance for that 
parameter is judged to be out of control, and the problem must be 
immediately identified and corrected. The analytical result for that 
parameter in the unspiked sample is suspect and may not be reported for 
regulatory compliance purposes.
    8.5  As part of the QC program for the laboratory, method accuracy 
for wastewater samples must be assessed and records must be maintained. 
After the analysis of five spiked wastewater samples as in Section 8.3, 
calculate the average percent recovery (P) and the standard deviation of 
the percent recovery (sp). Express the accuracy assessment as 
a percent recovery interval from P-2sp to P+2sp. 
If P=90% and sp=10%, for example, the accuracy interval is 
expressed as 70-110%. Update the accuracy assessment for each parameter 
on a regular basis (e.g. after each five to ten new accuracy 
measurements).
    8.6  It is recommended that the laboratory adopt additional quality 
assurance practices for use with this method. The specific practices 
that are most productive depend upon the needs of the laboratory and the 
nature of the samples. Field duplicates may be analyzed to assess the 
precision of the environmental measurements. When doubt exists over the 
identification of a peak on the chromatogram, confirmatory techniques 
such as gas chromatography with a dissimilar column, specific element 
detector, or mass spectrometer must be used. Whenever possible, the 
laboratory should analyze standard reference materials and participate 
in relevent performance evaluation studies.

            9. Sample Collection, Preservation, and Handling

    9.1  Grab samples must be collected in glass containers. 
Conventional sampling practices 8 should be followed, except 
that the bottle must not be prerinsed with sample before collection. 
Composite samples should be collected in refrigerated glass containers 
in accordance with the requirements of the program. Automatic sampling 
equipment must be as free as possible of Tygon tubing and other 
potential sources of contamination.
    9.2  All samples must be iced or refrigerated at 4  deg.C from the 
time of collection until extraction.
    9.3  All samples must be extracted within 7 days of collection and 
completely analyzed within 40 days of extraction.2

                          10. Sample Extraction

    10.1  Mark the water meniscus on the side of the sample bottle for 
later determination of sample volume. Pour the entire sample into a 2-L 
separatory funnel.

[[Page 171]]

    10.2  Add 60 mL of methylele chloride to the sample bottle, seal, 
and shake 30 s to rinse the inner surface. Transfer the solvent to the 
separatory funnel and extract the sample by shaking the funnel for 2 min 
with periodic venting to release excess pressure. Allow the organic 
layer to separate from the water phase for a minimum of 10 min. If the 
emulsion interface between layers is more than one-third the volume of 
the solvent layer, the analyst must employ mechanical techniques to 
complete the phase separation. The optimum technique depends upon the 
sample, but may include stirring, filtration of the emulsion through 
glass wool, centrifugation, or other physical methods. Collect the 
methylene chloride extract in a 250-mL Erlenmeyer flask.
    10.3  Add a second 60-mL volume of methylene chloride to the sample 
bottle and repeat the extraction procedure a second time, combining the 
extracts in the Erlenmeyer flask. Perform a third extraction in the same 
manner.
    10.4  Assemble a Kuderna-Danish (K-D) concentrator by attaching a 
10-mL concentrator tube to a 500-mL evaporative flask. Other 
concentration devices or techniques may be used in place of the K-D 
concentrator if the requirements of Section 8.2 are met.
    10.5  Pour the combined extract through a solvent-rinsed drying 
column containing about 10 cm of anhydrous sodium sulfate, and collect 
the extract in the K-D concentrator. Rinse the Erlenmeyer flask and 
column with 20 to 30 mL of methylene chloride to complete the 
quantitative transfer.
    10.6  Add one or two clean boiling chips to the evaporative flask 
and attach a three-ball Snyder column. Prewet the Snyder column by 
adding about 1 mL of methylene chloride to the top. Place the K-D 
apparatus on a hot water bath (60 to 65  deg.C) so that the concentrator 
tube is partially immersed in the hot water, and the entire lower 
rounded surface of the flask is bathed with hot vapor. Adjust the 
vertical position of the apparatus and the water temperature as required 
to complete the concentration in 15 to 20 min. At the proper rate of 
distillation the balls of the column will actively chatter but the 
chambers will not flood with condensed solvent. When the apparent volume 
of liquid reaches 1 to 2 mL, remove the K-D apparatus and allow it to 
drain and cool for at least 10 min.
    Note: The dichloribenzenes have a sufficiently high volatility that 
significant losses may occur in concentration steps if care is not 
exercised. It is important to maintain a constant gentle evaporation 
rate and not to allow the liquid volume to fall below 1 to 2 mL before 
removing the K-D apparatus from the hot water bath.
    10.7  Momentarily remove the Snyder column, add 50 mL of hexane and 
a new boiling chip, and reattach the Snyder column. Raise the tempeature 
of the water bath to 85 to 90  deg.C. Concentrate the extract as in 
Section 10.6, except use hexane to prewet the column. The elapsed time 
of concentration should be 5 to 10 min.
    10.8  Romove the Snyder column and rinse the flask and its lower 
joint into the concentrator tube with 1 to 2 mL of hexane. A 5-mL 
syringe is recommended for this operation. Stopper the concentrator tube 
and store refrigerated if further processing will not be performed 
immediately. If the extract will be stored longer than two days, it 
should be transferred to a Teflon-sealed screw-cap vial. If the sample 
extract requires no further cleanup, proceed with gas chromatographic 
analysis (Section 12). If the sample requires further cleanup, proceed 
to Section 11.
    10.9  Determine the original sample volume by refilling the sample 
bottle to the mark and transferring the liquid to a 1000-mL graduated 
cylinder. Record the sample volume to the nearest 5 mL.

                       11. Cleanup and Separation

    11.1  Cleanup procedures may not be necessary for a relatively clean 
sample matrix. If particular circumstances demand the use of a cleanup 
procedure, the analyst may use the procedure below or any other 
appropriate procedure. However, the analyst first must demonstrate that 
the requirements of Section 8.2 can be met using the method as revised 
to incorporate the cleanup procedure.
    11.2  Florisil column cleanup for chlorinated hydrocarbons:
    11.2.1  Adjust the sample extract to 10 mL with hexane.
    11.2.2  Place 12 g of Florisil into a chromatographic column. Tap 
the column to settle the Florisil and add 1 to 2 cm of anhydrous sodium 
sulfate to the top.
    11.2.3  Preelute the column with 100 mL of petroleum ether. Discard 
the eluate and just prior to exposure of the sodium sulfate layer to the 
air, quantitatively transfer the sample extract onto the column by 
decantation and subsequent petroleum ether washings. Discard the eluate. 
Just prior to exposure of the sodium sulfate layer to the air, begin 
eluting the column with 200 mL of petroleum ether and collect the eluate 
in a 500-mL K-D flask equipped with a 10-mL concentrator tube. This 
fraction should contain all of the chlorinated hydrocarbons.
    11.2.4  Concentrate the fraction as in Section 10.6, except use 
hexane to prewet the column. When the apparatus is cool, remove the 
Snyder column and rinse the flask and its lower joint into the 
concentrator tube with hexane. Analyze by gas chromatography (Section 
12).

[[Page 172]]

                         12. Gas Chromatography

    12.1  Table 1 summarizes the recommended operating conditions for 
the gas chromatograph. Included in this table are retention times and 
MDL that can be achieved under these conditions. Examples of the 
separations achieved by Columl 2 are shown in Figures 1 and 2. Other 
packed or capillary (open-tubular) columns, chromatographic conditions, 
or detectors may be used if the requirements of Section 8.2 are met.
    12.2  Calibrate the system daily as described in Section 7.
    12.3  If the internal standard calibration procedure is being used, 
the internal standard must be added to the sample extract and mixed 
throughly immediately before injection into the gas chromatograph.
    12.4  Inject 2 to 5 [mu]L of the sample extract or standard into the 
gas chromatograph using the solvent-flush techlique.9 Smaller 
(1.0 [mu]L) volumes may be injected if automatic devices are employed. 
Record the volume injected to the nearest 0.05 [mu]L, the total extract 
volume, and the resulting peak size in area or peak height units.
    12.5  Identify the parameters in the sample by comparing the 
retention times of the peaks in the sample chromatogram with those of 
the peaks in standard chromatograms. The width of the retention time 
window used to make identifications should be based upon measurements of 
actual retention time variations of standards over the course of a day. 
Three times the standard deviation of a retention time for a compound 
can be used to calculate a suggested window size; however, the 
experience of the analyst should weigh heavily in the interpretation of 
chromatograms.
    12.6  If the response for a peak exceeds the working range of the 
system, dilute the extract and reanalyze.
    12.7  If the measurement of the peak response is prevented by the 
presence of interferences, further cleanup is required.

                            13. Calculations

    13.1  Determine the concentration of individual compounds in the 
sample.
    13.1.1  If the external standard calibration procedure is used, 
calculate the amount of material injected from the peak response using 
the calibration curve or calibration factor determined in Section 7.2.2. 
The concentration in the sample can be calculated from Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.120

                                                              Equation 2

where:
A=Amount of material injected (ng).
Vi=Volume of extract injected ([mu]L).
Vt=Volume of total extract ([mu]L).
Vs=Volume of water extracted (mL).

    13.1.2  If the internal standard calibration procedure is used, 
calculate the concentration in the sample using the response factor (RF) 
determined in Section 7.3.2 and Equation 3.
[GRAPHIC] [TIFF OMITTED] TC15NO91.121

                                                              Equation 3

where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Is=Amount of internal standard added to each extract ([mu]g).
Vo=Volume of water extracted (L).

    13.2  Report results in [mu]g/L without correction for recovery 
data. All QC data obtained should be reported with the sample results.

                         14. Method Performance

    14.1  The method detection limit (MDL) is defined as the minimum 
concentration of a substance that can be measured and reported with 99% 
confidence that the value is above zero.1 The MDL 
concentrations listed in Table 1 were obtained using reagent 
water.10 Similar results were achieved using representative 
wastewaters. The MDL actually achieved in a given analysis will vary 
depending on instrument sensitivity and matrix effects.
    14.2  This method has been tested for linearity of spike recovery 
from reagent water and has been demonstrated to be applicable over the 
concentration range from 4xMDL to 1000xMDL.10
    14.3  This method was tested by 20 laboratories using reagent water, 
drinking water, surface water, and three industrial wastewaters spiked 
at six concentrations over the range 1.0 to 356 [mu]g/L.11 
Single operator precision, overall precision, and method accuracy were 
found to be directly related to the concentration of the parameter and 
essentially independent of the sample matrix. Linear equations to 
describe these relationships are presented in Table 3.

                               References

    1. 40 CFR part 136, appendix B.
    2. ``Determination of Chlorinated Hydrocarbons In Industrial and 
Municipal Wastewaters, ``EPA 6090/4-84-ABC, National Technical 
Information Service, PBXYZ, Springfield, Virginia, 22161 November 1984.
    3. ASTM Annual Book of Standards, Part 31, D3694-78. ``Standard 
Practices for Preparation of Sample Containers and for Preservation of 
Organic Constituents,'' American

[[Page 173]]

Society for Testing and Materials, Philadelphia.
    4. ``Carcinogens--Working With Carcinogens,'' Department of Health, 
Education, and Welfare, Public Health Service, Center for Disease 
Control, National Institute for Occupational Safety and Health, 
Publication No. 77-206, August 1977.
    5. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR 
part 1910), Occupational Safety and Health Administration, OSHA 2206 
(Revised, January 1976).
    6. ``Safety in Academic Chemistry Laboratories,'' American Chemical 
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
    7. Provost, L.P., and Elder, R.S. ``Interpretation of Percent 
Recovery Data,''American Laboratory, 15, 58-63 (1983). (The value 2.44 
used in the equation in Section 8.3.3 is two times the value 1.22 
derived in this report.)
    8. ASTM Annual Book of Standards, Part 31, D3370-76. ``Standard 
Practices for Sampling Water,'' American Society for Testing and 
Materials, Philadelphia.
    9. Burke, J.A. ``Gas Chromatography for Pesticide Residue Analysis; 
Some Practical Aspects,'' Journal of the Association of Official 
Analytical Chemists, 48, 1037 (1965).
    10. ``Development of Detection Limits, EPA Method 612, Chlorinated 
Hydrocarbons,'' Special letter report for EPA Contract 68-03-2625, U.S. 
Environmental Protection Agency, Environmental Monitoring and Support 
Laboratory, Cincinnati, Ohio 45268.
    11. ``EPA Method Study Method 612--Chlorinated Hydrocarbons,'' EPA 
600/4-84-039, National Technical Information Service, PB84-187772, 
Springfield, Virginia 22161, May 1984.
    12. ``Method Performance for Hexachlorocyclopentadiene by Method 
612,'' Memorandum from R. Slater, U.S. Environmental Protection Agency, 
Environmental Monitoring and Support Laboratory, Cincinnati, Ohio 45268, 
December 7, 1983.

     Table 1--Chromatographic Conditions and Method Detection Limits
------------------------------------------------------------------------
                                     Retention time (min)       Method
                                  --------------------------  detection
            Parameter                                           limit
                                     Column 1     Column 2    ([mu]g/L)
------------------------------------------------------------------------
1,3-Dichlorobenzene..............          4.5          6.8         1.19
Hexachloroethane.................          4.9          8.3         0.03
1,4-Dichlorobenzene..............          5.2          7.6         1.34
1,2-Dichlorobenzene..............          6.6          9.3         1.14
Hexachlorobutadiene..............          7.7         20.0         0.34
1,2,4-Trichlorobenzene...........         15.5         22.3         0.05
Hexachlorocyclopentadiene........           nd       c 16.5         0.40
2-Chloronaphthalene..............        a 2.7        b 3.6         0.94
Hexachlorobenzene................        a 5.6       b 10.1        0.05
------------------------------------------------------------------------
Column 1 conditions: Supelcoport (100/120 mesh) coated with 1% SP-1000
  packed in a 1.8 m x 2 mm ID glass column with 5% methane/95% argon
  carrier gas at 25 mL/min. flow rate. Column temperature held
  isothermal at 65  deg.C, except where otherwise indicated.
Column 2 conditions: Supelcoport (80/100 mesh) coated with 1.5% OV-1/
  2.4% OV-225 packed in a 1.8 m x 2 mm ID glass column with 5% methane/
  95% argon carrier gas at 25 mL/min. flow rate. Column temperature held
  isothermal at 75  deg.C, except where otherwise indicated.
nd=Not determined.
a 150  deg.C column temperature.
b 165  deg.C column temperature.
c 100  deg.C column temperature.


                                   Table 2--QC Acceptance Criteria--Method 612
----------------------------------------------------------------------------------------------------------------
                                                                   Test                   Range for X  Range for
                           Parameter                              conc.     Limit for s    ([mu]g/L)     P, Ps
                                                                ([mu]g/L)  ([mu]g[sol]L)               (percent)
----------------------------------------------------------------------------------------------------------------
2-Chloronaphthalene...........................................        100         37.3     29.5-126.9      9-148
1,2-Dichlorobenzene...........................................        100         28.3     23.5-145.1      9-160
1,3-Dichlorobenzene...........................................        100         26.4      7.2-138.6      D-150
1,4-Dichlorobenzene...........................................        100         20.8     22.7-126.9     13-137
Hexachlorobenzene.............................................         10          2.4       2.6-14.8     15-159
Hexachlorobutadiene...........................................         10          2.2         D-12.7      D-139
Hexachlorocyclopentadiene.....................................         10          2.5         D-10.4      D-111
Hexachloroethane..............................................         10          3.3       2.4-12.3      8-139
1,2,4-Trichlorobenzene........................................        100         31.6     20.2-133.7      5-149
----------------------------------------------------------------------------------------------------------------
s=Standard deviation of four recovery measurements, in [mu]g/L (Section 8.2.4).
X=Average recovery for four recovery measurements, in [mu]g/L (Section 8.2.4).
P, Ps=Percent recovery measured (Section 8.3.2, Section 8.4.2).
D=Detected; result must be greater than zero.
 
Note: These criteria are based directly upon the method performance data in Table 3. Where necessary, the limits
  for recovery have been broadened to assure applicability of the limits to concentrations below those used to
  develop Table 3.


[[Page 174]]


                Table 3--Method Accuracy and Precision as Functions of Concentration--Method 612
----------------------------------------------------------------------------------------------------------------
                                                                      Single analyst
               Parameter                Acccuracy, as recovery,   precision, sr' ([mu]g/   Overall precision, S'
                                              X' ([mu]g/L)                  L)                   ([mu]g/L)
----------------------------------------------------------------------------------------------------------------
2-Chloronaphthalene...................  0.75C+3.21               0.28X-1.17               0.38X-1.39
1,2-Dichlorobenzene...................  0.85C-0.70               0.22X-2.95               0.41X-3.92
1,3-Dichlorobenzene...................  0.72C+0.87               0.21X-1.03               0.49X-3.98
1,4-Dichlorobenzene...................  0.72C+2.80               0.16X-0.48               0.35X-0.57
Hexachlorobenzene.....................  0.87C-0.02               0.14X+0.07               0.36X-0.19
Hexachlorobutadiene...................  0.61C+0.03               0.18X+0.08               0.53X-0.12
Hexachlorocyclopentadiene a...........  0.47C                    0.24X                    0.50X
Hexachloroethane......................  0.74C-0.02               0.23X+0.07               0.36X-0.00
1,2,4-Trichlorobenzene................  0.76C+0.98               0.23X-0.44               0.40X-1.37
----------------------------------------------------------------------------------------------------------------
X'=Expected recovery for one or more measurements of a sample containing a concentration of C, in [mu]g/L.
sr'=Expected single analyst standard deviation of measurements at an average concentration found of X, in [mu]g/
  L.
S'=Expected interlaboratory standard deviation of measurements at an average concentration found of X, in [mu]g/
  L.
C=True value for the concentration, in [mu]g/L.
X=Average recovery found for measurements of samples containing a concentration of C, in [mu]g/L.
 
a Estimates based upon the performance in a single laboratory.\12\


[[Page 175]]

[GRAPHIC] [TIFF OMITTED] TC02JY92.036


[[Page 176]]

[GRAPHIC] [TIFF OMITTED] TC02JY92.037


[[Page 177]]

             Method 613--2,3,7,8-Tetrachlorodibenzo-p-Dioxin

                        1. Scope and Application

    1.1  This method covers the determination of 2,3,7,8-
tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD). The following parameter may 
be determined by this method:

------------------------------------------------------------------------
                                                    STORET
                    Parameter                        No.       GAS No.
------------------------------------------------------------------------
2,3,7,8-TCDD.....................................    34675     1746-01-6
------------------------------------------------------------------------

    1.2  This is a gas chromatographic/mass spectrometer (GC/MS) method 
applicable to the determination of 2,3,7,8-TCDD in municipal and 
industrial discharges as provided under 40 CFR 136.1. Method 625 may be 
used to screen samples for 2,3,7,8-TCDD. When the screening test is 
positive, the final qualitative confirmation and quantification must be 
made using Method 613.
    1.3  The method detection limit (MDL, defined in Section 14.1) \1\ 
for 2,3,7,8-TCDD is listed in Table 1. The MDL for a specific wastewater 
may be different from that listed, depending upon the nature of 
interferences in the sample matrix.
    1.4  Because of the extreme toxicity of this compound, the analyst 
must prevent exposure to himself, of to others, by materials knows or 
believed to contain 2,3,7,8-TCDD. Section 4 of this method contains 
guidelines and protocols that serve as minimum safe-handling standards 
in a limited-access laboratory.
    1.5  Any modification of this method, beyond those expressly 
permitted, shall be considered as a major modification subject to 
application and approval of alternate test procedures under 40 CFR 136.4 
and 136.5.
    1.6  This method is restricted to use by or under the supervision of 
analysts experienced in the use of a gas chromatograph/mass spectrometer 
and in the interpretation of mass spectra. Each analyst must demonstrate 
the ability to generate acceptable results with this method using the 
procedure described in Section 8.2.

                          2. Summary of Method

    2.1  A measured volume of sample, approximately 1-L, is spiked with 
an internal standard of labeled 2,3,7,8-TCDD and extracted with 
methylene chloride using a separatory funnel. The methylene chloride 
extract is exchanged to hexane during concentration to a volume of 1.0 
mL or less. The extract is then analyzed by capillary column GC/MS to 
separate and measure 2,3,7,8-TCDD.\2,3\
    2.2  The method provides selected column chromatographic cleanup 
proceudres to aid in the elimination of interferences that may be 
encountered.

                            3. Interferences

    3.1  Method interferences may be caused by contaminants in solvents, 
reagents, glassware, and other sample processing hardware that lead to 
discrete artifacts and/or elevated backgrounds at the masses (m/z) 
monitored. All of these materials must be routinely demonstrated to be 
free from interferences under the conditions of the analysis by running 
laboratory reagent blanks as described in Section 8.1.3.
    3.1.1  Glassware must be scrupulously cleaned.\4\ Clean all 
glassware as soon as possible after use by rinsing with the last solvent 
used in it. Solvent rinsing should be followed by detergent washing with 
hot water, and rinses with tap water and distilled water. The glassware 
should then be drained dry, and heated in a muffle furnace at 400  deg.C 
for 15 to 30 min. Some thermally stable materials, such as PCBs, may not 
be eliminated by the treatment. Solvent rinses with acetone and 
pesticide quality hexane may be substituted for the muffle furnace 
heating. Thorough rinsing with such solvents usually eliminates PCB 
interference. Volumetric ware should not be heated in a muffle furnace. 
After drying and cooling, glassware should be sealed and stored in a 
clean environment to prevent any accumulation of dust or other 
contaminants. Store inverted or capped with aluminum foil.
    3.1.2  The use of high purity reagents and solvents helps to 
mininmize interference problems. Purification of solvents by 
distillation in all-glass systems may be required.
    3.2  Matrix interferences may be caused by contaminants that are 
coextracted from the sample. The extent of matrix interferences will 
vary considerably from source to source, depending upon the nature and 
diversity of the industrial complex or municipality being sampled. 
2,3,7,8-TCDD is often associated with other interfering chlorinated 
compounds which are at concentrations several magnitudes higher than 
that of 2,3,7,8-TCDD. The cleanup producers in Section 11 can be used to 
overcome many of these interferences, but unique samples may require 
additional cleanup approaches 1,5-7 to eliminate false 
positives and achieve the MDL listed in Table 1.
    3.3  The primary column, SP-2330 or equivalent, resolves 2,3,7,8-
TCDD from the other 21 TCDD insomers. Positive results using any other 
gas chromatographic column must be confirmed using the primary column.

                                4. Safety

    4.1  The toxicity or carcinogenicity of each reagent used in this 
method has not been precisely defined; however, each chemical compound 
should be treated as a potential health hazard. From this viewpoint, 
exposure to these chemicals must be reduced to

[[Page 178]]

the lowest possible level by whatever means available. The laboratory is 
responsible for maintaining a current awareness file of OSHA regulations 
regarding the safe handling of the chemicals specified in this method. A 
reference file of material data handling sheets should also be made 
available to all personnel involved in the chemical analysis. Additional 
references to laboratory safety are available and have been identified 
\8\-\10\ for the information of the analyst. Benzene and 
2,3,7,8-TCDD have been identified as suspected human or mammalian 
carcinogens.
    4.2  Each laboratory must develop a strict safety program for 
handling 2,3,7,8-TCDD. The following laboratory practices are 
recommended:
    4.2.1  Contamination of the laboratory will be minimized by 
conducting all manipulations in a hood.
    4.2.2  The effluents of sample splitters for the gas chromatograph 
and roughing pumps on the GC/MS should pass through either a column of 
activated charcoal or be bubbled through a trap containing oil or high-
boiling alcohols.
    4.2.3  Liquid waste should be dissolved in methanol or ethanol and 
irradiated with ultraviolet light with a wavelength greater than 290 nm 
for several days. (Use F 40 BL lamps or equivalent). Analyze liquid 
wastes and dispose of the solutions when 2,3,7,8-TCDD can no longer be 
detected.
    4.3  Dow Chemical U.S.A. has issued the following precautimns 
(revised November 1978) for safe handling of 2,3,7,8-TCDD in the 
laboratory:
    4.3.1  The following statements on safe handling are as complete as 
possible on the basis of available toxicological information. The 
precautions for safe handling and use are necessarily general in nature 
since detailed, specific recommendations can be made only for the 
particular exposure and circumstances of each individual use. Inquiries 
about specific operations or uses may be addressed to the Dow Chemical 
Company. Assistance in evaluating the health hazards of particular plant 
conditions may be obtained from certain consulting laboratories and from 
State Departments of Health or of Labor, many of which have an 
industrial health service. 2,3,7,8-TCDD is extremely toxic to laboratory 
animals. However, it has been handled for years without injury in 
analytical and biological laboratories. Techniques used in handling 
radioactive and infectious materials are applicable to 2,3,7,8,-TCDD.
    4.3.1.1  Protective equipment--Throw-away plastic gloves, apron or 
lab coat, safety glasses, and a lab hood adequate for radioactive work.
    4.3.1.2  Training--Workers must be trained in the proper method of 
removing contaminated gloves and clothing without contacting the 
exterior surfaces.
    4.3.1.3  Personal hygiene--Thorough washing of hands and forearms 
after each manipulation and before breaks (coffee, lunch, and shift).
    4.3.1.4  Confinement--Isolated work area, posted with signs, 
segregated glassware and tools, plastic-backed absorbent paper on 
benchtops.
    4.3.1.5  Waste--Good technique includes minimizing contaminated 
waste. Plastic bag liners should be used in waste cans. Janitors must be 
trained in the safe handling of waste.
    4.3.1.6  Disposal of wastes--2,3,7,8-TCDD decomposes above 800 
deg.C. Low-level waste such as absorbent paper, tissues, animal remains, 
and plastic gloves may be burned in a good incinerator. Gross quantities 
(milligrams) should be packaged securely and disposed through commercial 
or governmental channels which are capable of handling high-level 
radioactive wastes or extremely toxic wastes. Liquids should be allowed 
to evaporate in a good hood and in a disposable container. Residues may 
then be handled as above.
    4.3.1.7  Decontamination--For personal decontamination, use any mild 
soap with plenty of scrubbing action. For decontamination of glassware, 
tools, and surfaces, Chlorothene NU Solvent (Trademark of the Dow 
Chemical Company) is the least toxic solvent shown to be effective. 
Satisfactory cleaning may be accomplished by rinsing with Chlorothene, 
then washing with any detergent and water. Dishwater may be disposed to 
the sewer. It is prudent to minimize solvent wastes because they may 
require special disposal through commercial sources which are expensive.
    4.3.1.8  Laundry--Clothing known to be contaminated should be 
disposed with the precautions described under Section 4.3.1.6. Lab coats 
or other clothing worn in 2,3,7,8-TCDD work areas may be laundered.
    Clothing should be collected in plastic bags. Persons who convey the 
bags and launder the clothing should be advised of the hazard and 
trained in proper handling. The clothing may be put into a washer 
without contact if the launderer knows the problem. The washer should be 
run through a cycle before being used again for other clothing.
    4.3.1.9  Wipe tests--A useful method of determining cleanliness of 
work surfaces and tools is to wipe the surface with a piece of filter 
paper. Extraction and analysis by gas chromatography can achieve a limit 
of sensitivity of 0.1 [mu]g per wipe. Less than 1 [mu]g of 2,3,7,8-TCDD 
per sample indicates acceptable cleanliness; anything higher warrants 
further cleaning. More than 10 [mu]g on a wipe sample constitutes an 
acute hazard and requires prompt cleaning before further use of the 
equipment or work space. A high (10 [mu]g)

[[Page 179]]

2,3,7,8-TCDD level indicates that unacceptable work practices have been 
employed in the past.
    4.3.1.10  Inhalation--Any procedure that may produce airborne 
contamination must be done with good ventilation. Gross losses to a 
ventilation system must not be allowed. Handling of the dilute solutions 
normally used in analytical and animal work presents no inhalation 
hazards except in the case of an accident.
    4.3.1.11  Accidents--Remove contaminated clothing immediately, 
taking precautions not to contaminate skin or other articles. Wash 
exposed skin vigorously and repeatedly until medical attention is 
obtained.

                       5. Apparatus and Materials

    5.1  Sampling equipment, for discrete or composite sampling.
    5.1.1  Grab sample bottle--1-L or 1-qt, amber glass, fitted with a 
screw cap lined with Teflon. Foil may be substituted for Teflon if the 
sample is not corrosive. If amber bottles are not available, protect 
samples from light. The bottle and cap liner must be washed, rinsed with 
acetone or methylene chloride, and dried before use to minimize 
contamination.
    5.1.2  Automatic sampler (optional)--The sampler must incorporate 
glass sample containers for the collection of a minimum of 250 mL of 
sample. Sample containers must be kept refrigerated at 4  deg.C and 
protected from light during compositing. If the sampler uses a 
peristaltic pump, a minimum length of compressible silicone rubber 
tubing may be used. Before use, however, the compressible tubing should 
be thoroughly rinsed with methanol, followed by repeated rinsings with 
distilled water to minimize the potential for contamination of the 
sample. An integrating flow meter is required to collect flow 
proportional composites.
    5.1.3  Clearly label all samples as ``POISON'' and ship according to 
U.S. Department of Transportation regulations.
    5.2  Glassware (All specifications are suggested. Catalog numbers 
are included for illustration only.):
    5.2.1  Separatory funnels--2-L and 125-mL, with Teflon stopcock.
    5.2.2  Concentrator tube, Kuderna-Danish--10-mL, graduated (Kontes 
K-570050-1025 or equivalent). Calibration must be checked at the volumes 
employed in the test. Ground glass stopper is used to prevent 
evaporation of extracts.
    5.2.3  Evaporative flask, Kuderna-Danish--500-mL (Kontes K-570001-
0500 or equivalent). Attach to concentrator tube with springs.
    5.2.4  Snyder column, Kuderna-Danish--Three-ball macro (Kontes K-
503000-0121 or equivalent).
    5.2.5  Snyder column, Kuderna-Danish--Two-ball micro (Kontes K-
569001-0219 or equivalent).
    5.2.6  Vials--10 to 15-mL, amber glass, with Teflon-lined screw cap.
    5.2.7  Chromatographic column--300 mm long x 10 mm ID, with Teflon 
stopcock and coarse frit filter disc at bottom.
    5.2.8  Chromatographic column--400 mm long x 11 mm ID, with Teflon 
stopcock and coarse frit filter disc at bottom.
    5.3  Boiling chips--Approximately 10/40 mesh. Heat to 400  deg.C for 
30 min or Soxhlet extract with methylene chloride.
    5.4  Water bath--Heated, with concentric ring cover, capable of 
temperature control (2  deg.C). The bath should be used in a 
hood.
    5.5  GC/MS system:
    5.5.1  Gas chromatograph--An analytical system complete with a 
temperature programmable gas chromatograph and all required accessories 
including syringes, analytical columns, and gases. The injection port 
must be designed for capillary columns. Either split, splitless, or on-
column injection techniques may be employed, as long as the requirements 
of Section 7.1.1 are achieved.
    5.5.2  Column--60 m long x 0.25 mm ID glass or fused silica, coated 
with SP-2330 (or equivalent) with a film thickness of 0.2 [mu]m. Any 
equivalent column must resolve 2, 3, 7, 8-TCDD from the other 21 TCDD 
isomers.16
    5.5.3  Mass spectrometer--Either a low resolution mass spectrometer 
(LRMS) or a high resolution mass spectrometer (HRMS) may be used. The 
mass spectrometer must be equipped with a 70 V (nominal) ion source and 
be capable of aquiring m/z abundance data in real time selected ion 
monitoring (SIM) for groups of four or more masses.
    5.5.4  GC/MS interface--Any GC to MS interface can be used that 
achieves the requirements of Section 7.1.1. GC to MS interfaces 
constructed of all glass or glass-lined materials are recommended. Glass 
surfaces can be deactivated by silanizing with dichlorodimethylsilane. 
To achieve maximum sensitivity, the exit end of the capillary column 
should be placed in the ion source. A short piece of fused silica 
capillary can be used as the interface to overcome problems associated 
with straightening the exit end of glass capillary columns.
    5.5.5  The SIM data acquired during the chromatographic program is 
defined as the Selected Ion Current Profile (SICP). The SICP can be 
acquired under computer control or as a real time analog output. If 
computer control is used, there must be software available to plot the 
SICP and report peak height or area data for any m/z in the SICP between 
specified time or scan number limits.
    5.6  Balance--Analytical, capable of accurately weighing 0.0001 g.

                               6. Reagents

    6.1  Reagent water--Reagent water is defined as a water in which an 
interferent is not observed at the MDL of 2, 3, 7, 8-TCDD.

[[Page 180]]

    6.2  Sodium hydroxide solution (10 N)--Dissolve 40 g of NaOH (ACS) 
in reagent water and dilute to 100 mL. Wash the solution with methylene 
chloride and hexane before use.
    6.3  Sodium thiosulfate--(ACS) Granular.
    6.4  Sulfuric acid--Concentrated (ACS, sp. gr. 1.84).
    6.5  Acetone, methylene chloride, hexane, benzene, ortho-xylene, 
tetradecane--Pesticide quality or equivalent.
    6.6  Sodium sulfate--(ACS) Granular, anhydrous. Purify by heating at 
400  deg.C for 4 h in a shallow tray.
    6.7  Alumina--Neutral, 80/200 mesh (Fisher Scientific Co., No. A-540 
or equivalent). Before use, activate for 24 h at 130  deg.C in a foil-
covered glass container.
    6.8  Silica gel--High purity grade, 100/120 mesh (Fisher Scientific 
Co., No. S-679 or equivalent).
    6.9  Stock standard solutions (1.00 [mu]g/[mu]L)--Stock standard 
solutimns can be prepared from pure standard materials or purchased as 
certified solutions. Acetone should be used as the solvent for spiking 
solutions; ortho-xylene is recommended for calibration standards for 
split injectors; and tetradecane is recommended for splitless or on-
colum injectors. Analyze stock internal standards to verify the absence 
of native 2,3,7,8-TCDD.
    6.9.1  Prepare stock standard solutions of 2,3,7,8-TCDD (mol wt 320) 
and either 37C14 2,3,7,8-TCDD (mol wt 328) or 
13C112 2,3,7,8-TCDD (mol wt 332) in an isolated 
area by accurately weighing about 0.0100 g of pure material. Dissolve 
the material in pesticide quality solvent and dilute to volume in a 10-
mL volumetric flask. When compound purity is assayed to be 96% or 
greater, the weight can be used without correction to calculate the 
concentration of the stock standard. Commercially prepared stock 
standards can be used at any concentration if they are certified by the 
manufacturer or by an independent source.
    6.9.2  Transfer the stock standard solutions into Teflon-sealed 
screw-cap bottles. Store in an isolated refrigerator protected from 
light. Stock standard solutions should be checked frequently for signs 
of degradation or evaporation, especially just prior to preparing 
calibration standards or spiking solutions from them.
    6.9.3  Stock standard solutions must be replaced after six months, 
or sooner if comparison with check standards indicates a problem.
    6.10  Internal standard spiking solution (25 ng/mL)--Using stock 
standard solution, prepare a spiking solution in acetone of either 
13 Cl12 or 37 Cl4 2,3,7,8-
TCDD at a concentration of 25 ng/mL. (See Section 10.2)
    6.11  Quality control check sample concentrate--See Section 8.2.1.

                             7.  Calibration

    7.1  Establish gas chromatograhic operating conditions equivalent to 
those given in Table 1 and SIM conditions for the mass spectrometer as 
described in Section 12.2 The GC/MS system must be calibrated using the 
internal standard technique.
    7.1.1  Using stock standards, prepare calibration standards that 
will allow measurement of relative response factors of at least three 
concentration ratios of 2,3,7,8-TCDD to internal standard. Each 
calibration standard must be prepared to contain the internal standard 
at a concentration of 25 ng/mL. If any interferences are contributed by 
the internal standard at m/z 320 and 322, its concentration may be 
reduced in the calibration standards and in the internal standard 
spiking solution (Section 6.10). One of the calibration standards should 
contain 2,3,7,8-TCDD at a concentration near, but above, the MDL and the 
other 2,3,7,8-TCDD concentrations should correspond to the expected 
range of concentrations found in real samples or should define the 
working range of the GC/MS system.
    7.1.2  Using injections of 2 to 5 [mu]L, analyze each calibration 
standardaccording to Section 12 and tabulate peak height or area 
response against the concentration of 2,3,7,8-TCDD and internal 
standard. Calculate response factors (RF) for 2,3,7,8-TCDD using 
Equation 1.
[GRAPHIC] [TIFF OMITTED] TC15NO91.122

                                                              Equation 1

where:
As=SIM response for 2,3,7,8-TCDD m/z 320.
Ais=SIM response for the internal standard, m/z 332 for \13\ 
C12 2,3,7,8-TCDD m/z 328 for 37 Cl4 
2,3,7,8-TCDD.
Cis=Concentration of the internal standard ([mu]g/L).
Cs=Concentration of 2,3,7,8-TCDD ([mu]g/L).

If the RF value over the working range is a constant (<10% relative 
standard deviation, RSD), the RF can be assumed to be invariant and the 
average RF can be used for calculations. Alternatively, the results can 
be used to plot a calibration curve of response ratios, As/
Ais, vs. RF.
    7.1.3  The working calibration curve or RF must be verified on each 
working day by the measurement of one or more 2,3,7,8-TCDD calibration 
standards. If the response for 2,3,7,8-TCDD varies from the predicted 
response by more than 15%, the test must be repeated using a 
fresh calibration standard. Alternatively, a new calibration curve must 
be prepared.

[[Page 181]]

    7.2  Before using any cleanup procedure, the analyst must process a 
series of calibration standards through the procedure to validate 
elution patterns and the absence of interferences from the reagents.

                           8. Quality Control

    8.1  Each laboratory that uses this method is required to operate a 
formal quality control program. The minimum requirements of this program 
consist of an initial demonstration of laboratory capability and an 
ongoing analysis of spiked samples to evaluate and document data 
quality. The laboratory must maintain records to document the quality of 
data that is generated. Ongoing data quality checks are compared with 
established performance criteria to determine if the results of analyses 
meet the performance characteristics of the method. When results of 
sample spikes indicate atypical method performance, a quality control 
check standard must be analyzed to confirm that the measurements were 
performed in an in-control mode of operation.
    8.1.1  The analyst must make an initial, one-time, demonstration of 
the ability to generate acceptable accuracy and precision with this 
method. This ability is established as described in Section 8.2.
    8.1.2  In recognition of advances that are occurring in 
chromatography, the analyst is permitted certain options (detailed in 
Sections 10.5, 11.1, and 12.1) to improve the separations or lower the 
cost of measurements. Each time such a modification is made to the 
method, the analyst is required to repeat the procedure in Section 8.2
    8.1.3  Before processing any samples, the analyst must analyze a 
reagent water blank to demonstrate that interferences from the 
analytical system and glassware are under control. Each time a set of 
samples is extracted or reagents are changed, a reagent water blank must 
be processed as a safeguard against laboratory contamination.
    8.1.4  The laboratory must, on an ongoing basis, spike and analyze a 
minimum of 10% of all samples with native 2,3,7,8-TCDD to monitor and 
evaluate laboratory data quality. This procedure is described in Section 
8.3.
    8.1.5  The laboratory must, on an ongoing basis, demonstrate through 
the analyses of quality control check standards that the operation of 
the measurement system is in control. This procedure is described in 
Section 8.4. The frequency of the check standard analyses is equivalent 
to 10% of all samples analyzed but may be reduced if spike recoveries 
from samples (Section 8.3) meet all specified quality control criteria.
    8.1.6  The laboratory must maintain performance records to document 
the quality of data that is generated. This procedure is described in 
Section 8.5.
    8.2  To establish the ability to generate acceptable accuracy and 
precision, the analyst must perform the following operations.
    8.2.1  A quality control (QC) check sample concentrate is required 
containing 2,3,7,8-TCDD at a concentration of 0.100 [mu]g/mL in acetone. 
The QC check sample concentrate must be obtained from the U.S. 
Environmental Protection Agency, Environmental Monitoring and Support 
Laboratory in Cincinnati, Ohio, if available. If not available from that 
source, the QC check sample concentrate must be obtained from another 
external source. If not available from either source above, the QC check 
sample concentrate must be prepared by the laboratory using stock 
standards prepared independently from those used for calibration.
    8.2.2  Using a pipet, prepare QC check samples at a concentration of 
0.100 [mu]g/L (100 ng/L) by adding 1.00 mL of QC check sample 
concentrate to each of four 1-L aliquots of reagent water.
    8.2.3  Analyze the well-mixed QC check samples according to the 
method beginning in Section 10.
    8.2.4  Calculate the average recovery (X) in [mu]g/L, and the 
standard deviation of the recovery (s) in [mu]g/L, for 2,3,7,8-TCDD 
using the four results.
    8.2.5  Compare s and (X) with the corresponding acceptance criteria 
for precision and accuracy, respectively, found in Table 2. If s and X 
meet the acceptance criteria, the system performance is acceptable and 
analysis of actual samples can begin. If s exceeds the precision limit 
or X falls outside the range for accuracy, the system performance is 
unacceptable for 2,3,7,8-TCDD. Locate and correct the source of the 
problem and repeat the test beginning with Section 8.2.2.
    8.3  The laboratory must, on an ongoing basis, spike at least 10% of 
the samples from each sample site being monitored to assess accuracy. 
For laboratories analyzing one to ten samples per month, at least one 
spiked sample per month is required.
    8.3.1  The concentration of the spike in the sample should be 
determined as follows:
    8.3.1.1  If, as in compliance monitoring, the concentration of 
2,3,7,8-TCDD in the sample is being checked against a regulatory 
concentration limit, the spike should be at that limit or 1 to 5 times 
higher than the background concentration determined in Section 8.3.2, 
whichever concentration would be larger.
    8.3.1.2  If the concentration of 2,3,7,8-TCDD in the sample is not 
being checked against a limit specific to that parameter, the spike 
should be at 0.100 [mu]g/L or 1 to 5 times higher than the background 
concentration determined in Section 8.3.2, whichever concentration would 
be larger.
    8.3.1.3  If it is impractical to determine background levels before 
spiking (e.g., maximum holding times will be exceeded), the

[[Page 182]]

spike concentration should be (1) the regulatory concentration limit, if 
any; or, if none (2) the larger of either 5 times higher than the 
expected background concentration or 0.100 [mu]g/L.
    8.3.2  Analyze one sample aliquot to determine the background 
concentration (B) of 2,3,7,8-TCDD. If necessary, prepare a new QC check 
sample concentrate (Section 8.2.1) appropriate for the background 
concentration in the sample. Spike a second sample aliquot with 1.0 mL 
of the QC check sample concentrate and analyze it to determine the 
concentration after spiking (A) of 2,3,7,8-TCDD. Calculate percent 
recovery (P) as 100(A-B)%T, where T is the known true value of the 
spike.
    8.3.3  Compare the percent recovery (P) for 2,3,7,8-TCDD with the 
corresponding QC acceptance criteria found in Table 2. These acceptance 
criteria were calculated to include an allowance for error in 
measurement of both the background and spike concentrations, assuming a 
spike to background ratio of 5:1. This error will be accounted for to 
the extent that the analyst's spike to background ratio approaches 
5:1.11 If spiking was performed at a concentration lower than 
0.100 [mu]g/L, the analyst must use either the QC acceptance criteria in 
Table 2, or optional QC acceptance criteria calculated for the specific 
spike concentration. To calculate optional acceptance criteria for the 
recovery of 2,3,7,8-TCDD: (1) Calculate accuracy (X') using the equation 
in Table 3, substituting the spike concentration (T) for C; (2) 
calculate overall precision (S') using the equation in Table 3, 
substituting X' for X; (3) calculate the range for recovery at the spike 
concentration as (100 X'/T)2.44(100 S'/T)%. 11
    8.3.4  If the recovery of 2,3,7,8-TCDD falls outside the designated 
range for recovery, a check standard must be analyzed as described in 
Section 8.4.
    8.4  If the recovery of 2,3,7,8-TCDD fails the acceptance criteria 
for recovery in Section 8.3, a QC check standard must be prepared and 
analyzed.
    Note: The frequency for the required analysis of a QC check standard 
will depend upon the complexity of the sample matrix and the performance 
of the laboratory.
    8.4.1  Prepare the QC check standard by adding 1.0 mL of QC check 
sample concentrate (Section 8.2.1 or 8.3.2) to 1 L of reagent water.
    8.4.2  Analyze the QC check standard to determine the concentration 
measured (A) of 2,3,7,8-TCDD. Calculate the percent recovery 
(Ps) as 100 (A/T)%, where T is the true value of the standard 
concentration.
    8.4.3  Compare the percent recovery (Ps) with the 
corresponding QC acceptance criteria found in Table 2. If the recovery 
of 2,3,7,8-TCDD falls outside the designated range, the laboratory 
performance is judged to be out of control, and the problem must be 
immediately identified and corrected. The analytical result for 2,3,7,8-
TCDD in the unspiked sample is suspect and may not be reported for 
regulatory compliance purposes.
    8.5  As part of the QC program for the laboratory, method accuracy 
for wastewater samples must be assessed and records must be maintained. 
After the analysis of five spiked wastewater samples as in Section 8.3, 
calculate the average percent recovery (P) and the spandard deviation of 
the percent recovery (sp). Express the accuracy assessment as 
a percent recovery interval from P-2sp to P+2sp. 
If P=90% and sp=10%, for example, the accuracy interval is 
expressed as 70-110%. Update the accuracy assessment on a regular basis 
(e.g. after each five to ten new accuracy measurements).
    8.6  It is recommended that the laboratory adopt additional quality 
assurance practices for use with this method. The specific practices 
that are most productive depend upon the needs of the laboratory and the 
nature of the samples. Field duplicates may be analyzed to assess the 
precision of the environmental measurements. Whenever possible, the 
laboratory should analyze standard reference materials and participate 
in relevant performance evaluation studies.

            9. Sample Collection, Preservation, and Handling

    9.1  Grab samples must be collected in glass containers. 
Conventional sampling practices 12 should be followed, except 
that the bottle must not be prerinsed with sample before collection. 
Composite samples should be collected in refrigerated glass containers 
in accordance with the requirements of the program. Automatic sampling 
equipment must be as free as possible of Tygon tubing and other 
potential sources of contamination.
    9.2  All samples must be iced or refrigerated at 4  deg.C and 
protected from light from the time of collection until extraction. Fill 
the sample bottles and, if residual chlorine is present, add 80 mg of 
sodium thiosulfate per liter of sample and mix well. EPA Methods 330.4 
and 330.5 may be used for measurement of residual chlorine.13 
Field test kits are available for this purpose.
    9.3  Label all samples and containers ``POISON'' and ship according 
to applicable U.S. Department of Transportation regulations.
    9.4  All samples must be extracted within 7 days of collection and 
completely analyzed within 40 days of extraction.2

                          10. Sample Extraction

    Caution: When using this method to analyze for 2,3,7,8-TCDD, all of 
the following operations must be performed in a limited-access 
laboratory with the analyst wearing full

[[Page 183]]

protective covering for all exposed skin surfaces. See Section 4.2.
    10.1  Mark the water meniscus on the side of the sample bottle for 
later determination of sample volume. Pour the entire sample into a 2-L 
separatory funnel.
    10.2  Add 1.00 mL of internal standard spiking solution to the 
sample in the separatory funnel. If the final extract will be 
concentrated to a fixed volume below 1.00 mL (Section 12.3), only that 
volume of spiking solution should be added to the sample so that the 
final extract will contain 25 ng/mL of internal standard at the time of 
analysis.
    10.3  Add 60 mL of methylene chloride to the sample bottle, seal, 
and shake 30 s to rinse the inner surface. Transfer the solvent to the 
separatory funnel and extract the sample by shaking the funnel for 2 
min. with periodic venting to release excess pressure. Allow the organic 
layer to separate from the water phase for a minimum of 10 min. If the 
emulsion interface between layers is more than one-third the vmlume of 
the solvent layer, the analyst must employ mechanical techniques to 
complete the phase separation. The optimum technique depends upon the 
sample, but may include stirring, filtration of the emulsion through 
glass wool, centrifugation, or other physical methods. Collect the 
methylene chloride extract in a 250-mL Erlenmeyer flask.
    10.4  Add a second 60-mL volume of methylene chloride to the sample 
bottle and repeat the extraction procedure a second time, combining the 
extracts in the Erlenmeyer flask. Perform a third extraction in the same 
manner.
    10.5  Assemble a Kuderna-Danish (K-D) concentrator by attaching a 
10-mL concentrator tube to a 500-mL evaporative flask. Other 
concentration devices or techniques may be used in place of the K-D 
concentrator if the requirements of Section 8.2 are met.
    10.6  Pour the combined extract into the K-D concentrator. Rinse the 
Erlenmeyer flask with 20 to 30 mL of methylele chloride to complete the 
quantitative transfer.
    10.7  Add one or two clean boiling chips to the evaporative flask 
and attach a three-ball Snyder column. Prewet the Snyder column by 
adding about 1 mL of methylene chloride to the top. Place the K-D 
apparatus on a hot water bath (60 to 65  deg.C) so that the concentrator 
tube is partially immersed in the hot water, and the entire lower 
rounded surface of the flask is bathed with hot vapor. Adjust the 
vertical position of the apparatus and the water temperature as required 
to complete the concentration in 15 to 20 min. At the proper rate of 
distillation the balls of the column will actively chatter but the 
chambers will not flood with condensed solvent. When the apparent volume 
of liquid reaches 1 mL, remove the K-D apparatus and allow it to drain 
and cool for at least 10 min.
    10.8  Momentarily remove the Snyder column, add 50 mL of hexane and 
a new boiling chip, and reattach the Snyder column. Raise the 
temperature of the water bath to 85 to 90 deg.C. Concentrate the extract 
as in Section 10.7, except use hexane to prewet the column. Remove the 
Snyder column and rinse the flask and its lower joint into the 
concentrator tube with 1 to 2 mL of hexane. A 5-mL syringe is 
recommended for this operation. Set aside the K-D glassware for reuse in 
Section 10.14.
    10.9  Pour the hexane extract from the concentrator tube into a 125-
mL separatory funnel. Rinse the concentrator tube four times with 10-mL 
aliquots of hexane. Combine all rinses in the 125-mL separatory funnel.
    10.10  Add 50 mL of sodium hydroxide solution to the funnel and 
shake for 30 to 60 s. Discard the aqueous phase.
    10.11  Perform a second wash of the organic layer with 50 mL of 
reagent water. Discard the aqueous phase.
    10.12  Wash the hexane layer with a least two 50-mL aliquots of 
concentrated sulfuric acid. Continue washing the hexane layer with 50-mL 
aliquots of concentrated sulfuric acid until the acid layer remains 
colorless. Discard all acid fractions.
    10.13  Wash the hexane layer with two 50-mL aliquots of reagent 
water. Discard the aqueous phases.
    10.14  Transfer the hexane extract into a 125-mL Erlenmeyer flask 
containing 1 to 2 g of anhydrous sodium sulfate. Swirl the flask for 30 
s and decant the hexane extract into the reassembled K-D apparatus. 
Complete the quantitative transfer with two 10-mL hexane rinses of the 
Erlenmeyer flask.
    10.15  Replace the one or two clean boiling chips and concentrate 
the extract to 6 to 10 mL as in Section 10.8.
    10.16  Add a clean boiling chip to the concentrator tube and attach 
a two-ball micro-Snyder column. Prewet the column by adding about 1 mL 
of hexane to the top. Place the micro-K-D apparatus on the water bath so 
that the concentrator tube is partially immersed in the hot water. 
Adjust the vertical position of the apparatus and the water temperature 
as required to complete the concentration in 5 to 10 min. At the proper 
rate of distillation the balls of the column will actively chatter but 
the chambers will not flood. When the apparent volume of liquid reaches 
about 0.5 mL, remove the K-D apparatus and allow it to drain and cool 
for at least 10 min. Remove the micro-Snyder column and rinse its lower 
joint into the concentrator tube with 0.2 mL of hexane.
    Adjust the extract volume to 1.0 mL with hexane. Stopper the 
concentrator tube and store refrigerated and protected from light if 
further processing will not be performed immediately. If the extract 
will be stored

[[Page 184]]

longer than two days, it should be transferred to a Teflon-sealed screw-
cap vial. If the sample extract requires no further cleanup, proceed 
with GC/MS analysis (Section 12). If the sample requires further 
cleanup, proceed to Section 11.
    10.17  Determine the original sample volume by refilling the sample 
bottle to the mark and transferring the liquid to a 1000-mL graduated 
cylinder. Record the sample volume to the nearest 5 mL.

                       11. Cleanup and Separation

    11.1  Cleanup procedures may not be necessary for a relatively clean 
sample matrix. If particular circumstances demand the use of a cleanup 
procedure, the analyst may use either procedure below or any other 
appropriate procedure.1,5-7 However, the analyst first must 
demonstrate that the requirements of Section 8.2 can be met using the 
method as revised to incorporate the cleanup procedure. Two cleanup 
column options are offered to the analyst in this section. The alumina 
column should be used first to overcome interferences. If background 
problems are still encountered, the silica gel column may be helpful.
    11.2  Alumina column cleanup for 2,3,7,8-TCDD:
    11.2.1  Fill a 300 mm long x 10 mm ID chromatographic column with 
activated alumina to the 150 mm level. Tap the column gently to settle 
the alumina and add 10 mm of anhydrous sodium sulfate to the top.
    11.2.2  Preelute the column with 50 mL of hexane. Adjust the elution 
rate to 1 mL/min. Discard the eluate and just prior to exposure of the 
sodium sulfate layer to the air, quantitatively transfer the 1.0-mL 
sample extract onto the column using two 2-mL portions of hexane to 
complete the transfer.
    11.2.3  Just prior to exposure of the sodium sulfate layer to the 
air, add 50 mL of 3% methylene chloride/95% hexane (V/V) and continue 
the elution of the column. Discard the eluate.
    11.2.4  Next, elute the column with 50 mL of 20% methylene chloride/
80% hexane (V/V) into a 500-mL K-D flask equipped with a 10-mL 
concentrator tube. Concentrate the collected fraction to 1.0 mL as in 
Section 10.16 and analyze by GC/MS (Section 12).
    11.3  Silica gel column cleanup for 2,3,7,8-TCDD:
    11.3.1  Fill a 400 mm long x 11 mm ID chromatmgraphic column with 
silica gel to the 300 mm level. Tap the column gently to settle the 
silica gel and add 10 mm of anhydrous sodium sulfate to the top.
    11.3.2  Preelute the column with 50 mL of 20% benzene/80% hexane (V/
V). Adjust the elution rate to 1 mL/min. Discard the eluate and just 
prior to exposure of the sodium sulfate layer to the air, quantitatively 
transfer the 1.0-mL sample extract onto the column using two 2-mL 
portions of 20% benzene/80% hexane to complete the transfer.
    11.3.3  Just prior to exposure of the sodium sulfate layer to the 
air, add 40 mL of 20% benzene/80% hexane to the column. Collect the 
eluate in a clean 500-mL K-D flask equipped with a 10-mL concentrator 
tube. Concentrate the collected fraction to 1.0 mL as in Section 10.16 
and analyze by GC/MS.

                           12. GC/MS Analysis

    12.1  Table 1 summarizes the recommended operating conditions for 
the gas chromatograph. Included in this table are retention times and 
MDL that can be achieved under these conditions. Other capillary columns 
or chromatographic conditions may be used if the requirements of 
Sections 5.5.2 and 8.2 are met.
    12.2  Analyze standards and samples with the mass spectrometer 
operating in the selected ion monitoring (SIM) mode using a dwell time 
to give at least seven points per peak. For LRMS, use masses at m/z 320, 
322, and 257 for 2,3,7,8-TCDD and either m/z 328 for 
37Cl4 2,3,7,8-TCDD or m/z 332 for 
13C12 2,3,7,8-TCDD. For HRMS, use masses at m/z 
319.8965 and 321.8936 for 2,3,7,8-TCDD and either m/z 327.8847 for 
37Cl4 2,3,7,8-TCDD or m/z 331.9367 for 
13C12 2,3,7,8-TCDD.
    12.3  If lower detection limits are required, the extract may be 
carefully evaporated to dryness under a gentle stream of nitrogen with 
the concentrator tube in a water bath at about 40  deg.C. Conduct this 
operation immediately before GC/MS analysis. Redissolve the extract in 
the desired final volume of ortho-xylene or tetradecane.
    12.4  Calibrate the system daily as described in Section 7.
    12.5  Inject 2 to 5 [mu]L of the sample extract into the gas 
chromatograph. The volume of calibration standard injected must be 
measured, or be the same as all sample injection volumes.
    12.6  The presence of 2,3,7,8-TCDD is qualitatively confirmed if all 
of the following criteria are achieved:
    12.6.1  The gas chromatographic column must resolve 2,3,7,8-TCDD 
from the other 21 TCDD isomers.
    12.6.2  The masses for native 2,3,7,8-TCDD (LRMS-m/z 320, 322, and 
257 and HRMS-m/z 320 and 322) and labeled 2,3,7,8-TCDD (m/z 328 or 332) 
must exhibit a simultaneous maximum at a retention time that matches 
that of native 2,3,7,8-TCDD in the calibration standard, with the 
performance specifications of the analytical system.
    12.6.3  The chlorine isotope ratio at m/z 320 and m/z 322 must agree 
to within10% of that in the calibration standard.
    12.6.4  The signal of all peaks must be greater than 2.5 times the 
noise level.
    12.7  For quantitation, measure the response of the m/z 320 peak for 
2,3,7,8-TCDD

[[Page 185]]

and the m/z 332 peak for \13\C12 2,3,7,8-TCDD or the m/z 328 
peak for 37Cl4 2,3,7,8-TCDD.
    12.8  Co-eluting impurities are suspected if all criteria are 
achieved except those in Section 12.6.3. In this case, another SIM 
analysis using masses at m/z 257, 259, 320 and either m/a 328 or m/z 322 
can be performed. The masses at m/z 257 and m/z 259 are indicative of 
the loss of one chlorine and one carbonyl group from 2,3,7,8-TCDD. If 
masses m/z 257 and m/z 259 give a chlorine isotope ratio that agrees to 
within 10% of the same cluster in the calibration standards, 
then the presence of TCDD can be confirmed. Co-eluting DDD, DDE, and PCB 
residues can be confirmed, but will require another injection using the 
appropriate SIM masses or full repetitive mass scans. If the response 
for 37Cl4 2,3,7,8-TCDD at m/z 328 is too large, 
PCB contamination is suspected and can be confirmed by examining the 
response at both m/z 326 and m/z 328. The 37Cl4 
2,3,7,8-TCDD internal standard gives negligible response at m/z 326. 
These pesticide residues can be removed using the alumina column cleanup 
procedure.
    12.9  If broad background interference restricts the sensitivity of 
the GC/MS analysis, the analyst should employ additional cleanup 
procedures and reanalyze by GC/MS.
    12.10  In those circumstances where these procedures do not yield a 
definitive conclusion, the use of high resolution mass spectrometry is 
suggested.5

                            13. Calculations

    13.1  Calculate the concentration of 2,3,7,8-TCDD in the sample 
using the response factor (RF) determined in Section 7.1.2 and Equation 
2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.123

                                                              Equation 2

where:
As=SIM response for 2,3,7,8-TCDD at m/z 320.
Ais=SIM response for the internal standard at m/z 328 or 332.
Is=Amount of internal standard added to each extract ([mu]g).
Vo=Volume of water extracted (L).

    13.2  For each sample, calculate the percent recovery of the 
internal standard by comparing the area of the m/z peak measured in the 
sample to the area of the same peak in the calibration standard. If the 
recovery is below 50%, the analyst should review all aspects of his 
analytical technique.
    13.3  Report results in [mu]g/L without correction for recovery 
data. All QC data obtained should be reported with the sample results.

                         14. Method Performance

    14.1  The method detection limit (MDL) is defined as the minimum 
concentration of a substance that can be measured and reported with 99% 
confidence that the value is above zero.1 The MDL 
concentration listed in Table 1 was obtained using reagent 
water.14 The MDL actually achieved in a given analysis will 
vary depending on instrument sensitivity and matrix effects.
    14.2  This method was tested by 11 laboratories using reagent water, 
drinking water, surface water, and three industrial wastewaters spiked 
at six concentrations over the range 0.02 to 0.20 [mu]g/L.15 
Single operator precision, overall precision, and method accuracy were 
found to be directly related to the concentration of the parameter and 
essentially independent of the sample matrix. Linear equations to 
describe these relationships are presented in Table 3.

                               References

    1. 40 CFR part 136, appendix B.
    2. ``Determination of TCDD in Industrial and Municipal 
Wastewaters,'' EPA 600/4-82-028, National Technical Information Service, 
PB82-196882, Springfield, Virginia 22161, April 1982.
    3. Buser, H.R., and Rappe, C. ``High Resolution Gas Chromatography 
of the 22 Tetrachlorodibenzo-p-dioxin Isomers,'' Analytical Chemistry, 
52, 2257 (1980).
    4. ASTM Annual Book of Standards, Part 31, D3694-78. ``Standard 
Practices for Preparation of Sample Containers and for Preservation of 
Organic Constituents,'' American Society for Testing and Materials, 
Philadelphia.
    5. Harless, R. L., Oswald, E. O., and Wilkinson, M. K. ``Sample 
Preparation and Gas Chromatography/Mass Spectrometry Determination of 
2,3,7,8-Tetrachlorodibenzo-p-dioxin,'' Analytical Chemistry, 52, 1239 
(1980).
    6. Lamparski, L. L., and Nestrick, T. J. ``Determination of Tetra-, 
Hepta-, and Octachlorodibenzo-p-dioxin Isomers in Particulate Samples at 
Parts per Trillion Levels,'' Analytical Chemistry, 52, 2045 (1980).
    7. Longhorst, M. L., and Shadoff, L. A. ``Determination of Parts-
per-Trillion Concentrations of Tetra-, Hexa-, and Octachlorodibenzo-p-
dioxins in Human Milk,'' Analytical Chemistry, 52, 2037 (1980).
    8. ``Carcinogens--Working with Carcinogens,'' Department of Health, 
Education, and Welfare, Public Health Service, Center for Disease 
Control, National Institute for Occupational Safety and Health, 
Publication No. 77-206, August 1977.
    9. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR 
part 1910), Occuptional Safety and Health Administration, OSHA 2206 
(Revised, January 1976).

[[Page 186]]

    10. ``Safety in Academic Chemistry Laboratories,'' American Chemical 
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
    11. Provost, L. P., and Elder, R. S., ``Interpretation of Percent 
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44 
used in the equation in Section 8.3.3 is two times the value 1.22 
derived in this report.)
    12. ASTM Annual Book of Standards, Part 31, D3370-76, ``Standard 
Practices for Sampling Water,'' American Society for Testing and 
Materials, Philadelphia.
    13. ``Methods, 330.4 (Titrimetric, DPD-FAS) and 330.5 
(Spectrophotometric DPD) for Chlorine, Total Residual,'' Methods for 
Chemical Analysis of Water and Wastes, EPA-600/4-79-020, U.S. 
Environmental Protection Agency, Environmental Monitoring and Support 
Laboratory, Cincinnati, Ohio 45268, March 1979.
    14. Wong, A.S. et al. ``The Determination of 2,3,7,8-TCDD in 
Industrial and Municipal Wastewaters, Method 613, Part 1--Development 
and Detection Limits,'' G. Choudhay, L. Keith, and C. Ruppe, ed., 
Butterworth Inc., (1983).
    15. ``EPA Method Study 26, Method 613: 2,3,7,8-Tetrachlorodibenzo-p-
dioxin,'' EPA 600/4-84-037, National Technical Information Service, 
PB84-188879, Springfield, Virginia 22161, May 1984.

     Table 1--Chromatographic Conditions and Method Detection Limit
------------------------------------------------------------------------
                                                                 Method
                                                    Retention  detection
                     Parameter                         time      limit
                                                      (min)    ([mu]g/L)
------------------------------------------------------------------------
2,3,7,8-TCDD......................................       13.1      0.002
------------------------------------------------------------------------
Column conditions: SP-2330 coated on a 60 m long x 0.25 mm ID glass
  column with hydrogen carrier gas at 40 cm/sec linear velocity,
  splitless injection using tetradecane. Column temperature held
  isothermal at 200 deg.C for 1 min, then programmed at 8 deg.C/min to
  250  deg.C and held. Use of helium carrier gas will approximately
  double the retention time.


               Table 2--QC Acceptance Criteria--Method 613
------------------------------------------------------------------------
                                 Test    Limit
                                conc.    for s     Range for X    Range
          Parameter            ([mu]g/  ([mu]g/     ([mu]g/L)     for P,
                                  L)       L)                     Ps (%)
------------------------------------------------------------------------
2,3,7,8-TCDD.................    0.100   0.0276   0.0523-0.1226   45-129
------------------------------------------------------------------------
s=Standard deviation of four recovery measurements, in [mu]g/L (Section
  8.2.4).
X=Average recovery for four recovery measurements, in [mu]g/L (Section
  8.2.4).
P, Ps=Percent recovery measured (Section 8.3.2, Section 8.4.2).
 
Note: These criteria are based directly upon the method performance data
  in Table 3. Where necessary, the limits for recovery have been
  broadened to assure applicability of the limits to concentrations
  below those used to develop Table 3.


                Table 3--Method Accuracy and Precision as Functions of Concentration--Method 613
----------------------------------------------------------------------------------------------------------------
                                                         Accuracy, as       Single analyst,
                      Parameter                          recovery, X '      precision, sr '   Overall precision,
                                                           ([mu]g/L)           ([mu]/L)         S ' ([mu]/g/L)
----------------------------------------------------------------------------------------------------------------
2,3,7,8-TCDD........................................       0.86C+0.00145       0.13X+0.00129       0.19X+0.00028
----------------------------------------------------------------------------------------------------------------
X'=Expected recovery for one or more measurements. of a sample containing a concentration of C, in [mu]g/L.
sr'=Expected single analyst standard deviation of measurements at an average concentration found of X, in [mu]g/
  L.
S'=Expected interlaboratory standard deviation of measurements at an average concentration found of X, in [mu]g/
  L.
C=True value for the concentration, in [mu]g/L.
X=Average recovery found for measurements of samples containing a concentration of C, in [mu]g/L.

                         Method 624--Purgeables

                        1. Scope and Application

    1.1  This method covers the determination of a number of purgeable 
organics. The following parameters may be determined by this method:

------------------------------------------------------------------------
                                                    STORET
                    Parameter                         No.      CAS No.
------------------------------------------------------------------------
Benzene..........................................     34030      71-43-2
Bromodichloromethane.............................     32101      75-27-4
Bromoform........................................     32104      75-25-2
Bromomethane.....................................     34413      74-83-9
Carbon tetrachloride.............................     32102      56-23-5
Chlorobenzene....................................     34301     108-90-7
Chloroethane.....................................     34311      75-00-3
2-Chloroethylvinyl ether.........................     34576     110-75-8
Chloroform.......................................     32106      67-66-3
Chloromethane....................................     34418      74-87-3
Dibromochloromethane.............................     32105     124-48-1
1,2-Dichlorobenzene..............................     34536      95-50-1
1,3-Dichlorobenzene..............................     34566     541-73-1
1,4-Dichlorobenzene..............................     34571     106-46-7
1,1-Dichloroethane...............................     34496      75-34-3
1,2-Dichloroethane...............................     34531     107-06-2
1,1-Dichloroethane...............................     34501      75-35-4
trans-1,2-Dichloroethene.........................     34546     156-60-5
1,2-Dichloropropane..............................     34541      78-87-5
cis-1,3-Dichloropropene..........................     34704   10061-01-5
trans-1,3-Dichloropropene........................     34699   10061-02-6
Ethyl benzene....................................     34371     100-41-4
Methylene chloride...............................     34423      75-09-2
1,1,2,2-Tetrachloroethane........................     34516      79-34-5
Tetrachloroethene................................     34475     127-18-4
Toluene..........................................     34010     108-88-3
1,1,1-Trichloroethene............................     34506      71-55-6
1,1,2-Trichloroethene............................     34511      79-00-5
Trichloroethane..................................     39180      79-01-6
Trichlorofluoromethane...........................     34488      75-69-4
Vinyl chloride...................................     39175      75-01-4
------------------------------------------------------------------------


[[Page 187]]

    1.2  The method may be extended to screen samples for acrolein 
(STORET No. 34210, CAS No. 107-02-8) and acrylonitrile (STORET No. 
34215, CAS No. 107-13-1), however, the preferred method for these two 
compounds in Method 603.
    1.3  This is a purge and trap gas chromatographic/mass spectrometer 
(GC/MS) method applicable to the determination of the compounds listed 
above in municipal and industrial discharges as provided under 40 CFR 
136.1.
    1.4  The method detection limit (MDL, defined in Section 14.1)\1\ 
for each parameter is listed in Table 1. The MDL for a specific 
wastewater may differ from those listed, depending upon the nature of 
interferences in the sample matrix.
    1.5  Any modification to this method, beyond those expressly 
permitted, shall be considered as a major modification subject to 
application and approval of alternate test procedures under 40 CFR 136.4 
and 136.5. Depending upon the nature of the modification and the extent 
of intended use, the applicant may be required to demonstrate that the 
modifications will produce equivalent results when applied to relevant 
wastewaters.
    1.6  This method is restricted to use by or under the supervision of 
analysts experienced in the operation of a purge and trap system and a 
gas chromatograph/mass spectrometer and in the interpretation of mass 
spectra. Each analyst must demonstrate the ability to generate 
acceptable results with this method using the procedure described in 
Section 8.2.

                          2. Summary of Method

    2.1  An inert gas is bubbled through a 5-mL water sample contained 
in a specially-designed purging chamber at ambient temperature. The 
purgeables are efficiently transferred from the aqueous phase to the 
vapor phase. The vapor is swept through a sorbent trap where the 
purgeables are trapped. After purging is completed, the trap is heated 
and backflushed with the inert gas to desorb the purgeables onto a gas 
chromatographic column. The gas chromatograph is temperature programmed 
to separate the purgeables which are then detected with a mass 
spectrometer.2,3

                            3. Interferences

    3.1  Impurities in the purge gas, organic compounds outgassing from 
the plumbing ahead of the trap, and solvent vapors in the laboratory 
account for the majority of contamination problems. The analytical 
system must be demonstated to be free from contamination under the 
conditions of the analysis by running laboratory reagent blanks as 
described in Section 8.1.3. The use of non-Teflon plastic tubing, non-
Teflon thread sealants, or flow controllers with rubber components in 
the purge and trap system should be avoided.
    3.2  Samples can be contaminated by diffusion of volatile organics 
(particularly fluorocarbons and methylene chloride) through the septum 
seal into the sample during shipment and storage. A field reagent blank 
prepared from reagent water and carried through the sampling and 
handling protocol can serve as a check on such contamination.
    3.3  Contamination by carry-over can occur whenever high level and 
low level samples are sequentially analyzed. To reduce carry-over, the 
purging device and sample syringe must be rinsed with reagent water 
between sample analyses. Whenever an unusually concentrated sample is 
encountered, it should be followed by an analysis of reagent water to 
check for cross contamination. For samples containing large amounts of 
water-soluble materials, suspended solids, high boiling compounds or 
high pureeable levels, it may be necessary to wash the purging device 
with a detergent solution, rinse it with distilled water, and then dry 
it in a 105  deg.C oven between analyses. The trap and other parts of 
the system are also subject to contamination; therefore, frequent 
bakeout and purging of the entire system may be required.

                                4. Safety

    4.1  The toxicity or carcinogenicity of each reagent used in this 
method has not been precisely defined; however, each chemical compound 
should be treated as a potential health hazard. From this viewpoint, 
exposure to these chemicals must be reduced to the lowest possible level 
by whatever means available. The laboratory is responsible for 
maintaining a current awareness file of OSHA regulations regarding the 
safe handling of the chemicals specified in this methmd. A reference 
file of material data handling sheets should also be made available to 
all personnel involved in the chemical analysis. Additional references 
to laboratory safety are available and have been identified 
4-6 for the information of the analyst.
    4.2.  The following parameters covered by this method have been 
tentatively classified as known or suspected, human or mammalian 
carcinogens: benzene, carbon tetrachloride, chloroform, 1,4-
dichlorobenzene, and vinyl chloride. Primary standards of these toxic 
compounds should be prepared in a hood. A NIOSH/MESA approved toxic gas 
respirator should be worn when the analyst handles high concentrations 
of these toxic compounds.

                       5. Apparatus and Materials

    5.1  Sampling equipment, for discrete sampling.
    5.1.1  Vial--25-mL capacity or larger, equipped with a screw cap 
with a hole in the

[[Page 188]]

center (Pierce 13075 or equivalent). Detergent wash, rinse with 
tap and distilled water, and dry at 105  deg.C before use.
    5.1.2  Septum--Teflon-faced silicane (Pierce 12722 or 
equivalent). Detergent wash, rinse with tap and distilled water, and dry 
at 105  deg.C for 1 h before use.
    5.2  Purge and trap system--The purge and trap system consists of 
three separate pieces of equipment: A purging device, trap, and 
desorber. Several complete systems are now commercially available.
    5.2.1  The purging device must be designed to accept 5-mL samples 
with a water column at least 3 cm deep. The gaseous head space between 
the water column and the trap must have a total volume of less than 15 
mL. The purge gas must pass though the water column as finely divided 
bubbles with a diameter of less than 3 mm at the origin. The purge gas 
must be introduced no more than 5 mm from the base of the water column. 
The purging device illustrated in Figure 1 meets these design criteria.
    5.2.2  The trap must be at least 25 cm long and have an inside 
diameter of at least 0.105 in. The trap must be packed to contain the 
following minimum lengths of adsorbents: 1.0 cm of methyl silicone 
coated packing (Section 6.3.2), 15 cm of 2,6-dyphenylene oxide polymer 
(Section 6.3.1), and 8 cm of silica gel (Section 6.3.3). The minimum 
specifications for the trap are illustrated in Figure 2.
    5.2.3  The desorber should be capable of rapidly heating the trap to 
180  deg.C. The polymer section of the trap should not be heated higher 
than 180  deg.C and the remaining sections should not exceed 200  deg.C. 
The desorber illustrated in Figure 2 meets these design criteria.
    5.2.4  The purge and trap system may be assembled as a separate unit 
or be coupled to a gas chromatograph as illustrated in Figures 3 and 4.
    5.3  GC/MS system:
    5.3.1  Gas chromatograph--An analytical system complete with a 
temperature programmable gas chromatograph suitable for on-column 
injection and all required accessories including syringes, analytical 
columns, and gases.
    5.3.2  Column--6 ft long x 0.1 in ID stainless steel or glass, 
packed with 1% SP-1000 on Carbopack B (60/80 mesh) or equivalent. This 
column was used to develop the method performance statements in Section 
14. Guidelines for the use of alternate column packings are provided in 
Section 11.1.
    5.3.3  Mass spectrometer--Capable of scanning from 20 to 260 amu 
every 7 s or less, utilizing 70 V (nominal) electron energy in the 
electron impact ionization mode, and producing a mass spectrum which 
meets all the criteria in Table 2 when 50 ng of 4-bromofluorobenzene 
(BFB) is injected through the GC inlet.
    5.3.4  GC/MS interface--Any GC to MS interface that gives acceptable 
calibration points at 50 ng or less per injection for each of the 
parameters of interest and achieves all acceptable performance criteria 
(Section 10) may be used. GC to MS interfaces constructed of all glass 
or glass-lined materials are recommended. Glass can be deactivated by 
silanizing with dichlorodimethylsilane.
    5.3.5  Data system--A computer system must be interfaced to the mass 
spectrometer that allows the continuous acquisition and storage on 
machine-readable media of all mass spectra obtained throughout the 
duration of the chromatographic program. The computer must have software 
that allows searching any GC/MS data file for specific m/z (masses) and 
plotting such m/z abundances versus time or scan number. This type of 
plot is defined as an Extracted Ion Current Profile (EICP). Software 
must also be available that allows integrating the abundance in any EICP 
between specified time or scan number limits.
    5.4  Syringes--5-mL, glass hypodermic with Luerlok tip (two each), 
if applicable to the purging device.
    5.5  Micro syringes--25-[mu]L, 0.006 in. ID needle.
    5.6  Syringe valve--2-way, with Luer ends (three each).
    5.7  Syringe--5-mL, gas-tight with shut-off valve.
    5.8  Bottle--15-mL, screw-cap, with Teflon cap liner.
    5.9  Balance--Analytical, capable of accurately weighing 0.0001 g.

                               6. Reagents

    6.1  Reagent water--Reagent water is defined as a water in which an 
interferent is not observed at the MDL of the parameters of interest.
    6.1.1  Reagent water can be generated by passing tap water through a 
carbon filter bed containing about 1 lb of activated carbon (Filtrasorb-
300, Calgon Corp., or equivalent).
    6.1.2  A water purification system (Millipore Super-Q or equivalent) 
may be used to generate reagent water.
    6.1.3  Reagent water may also be prepared by boiling water for 15 
min. Subsequently, while maintaining the temperature at 90  deg.C, 
bubble a contaminant-free inert gas through the water for 1 h. While 
still hot, transfer the water to a narrow mouth screw-cap bottle and 
seal with a Teflon-lined septum and cap.
    6.2  Sodium thiosulfate--(ACS) Granular.
    6.3  Trap materials:
    6.3.1  2,6-Diphenylene oxide polymer--Tenax, (60/80 mesh), 
chromatographic grade or equivalent.
    6.3.2  Methyl silicone packing--3% OV-1 on Chromosorb-W (60/80 mesh) 
or equivalent.
    6.3.3  Silica gel--35/60 mesh, Davison, grade-15 or equivalent.

[[Page 189]]

    6.4  Methanol--Pesticide quality or equivalent.
    6.5  Stock standard solutions--Stock standard solutions may be 
prepared from pure standard materials or purchased as certified 
solutions. Prepare stock standard solutions in methanol using assayed 
liquids or gases as appropriate. Because of the toxicity of some of the 
compounds, primary dilutions of these materials should be prepared in a 
hood. A NIOSH/MESA approved toxic gas respirator should be used when the 
analyst handles high concentrations of such materials.
    6.5.1  Place about 9.8 mL of methanol into a 10-mL ground glass 
stoppered volumetric flask. Allow the flask to stand, unstoppered, for 
about 10 min or until all alcohol wetted surfaces have dried. Weigh the 
flask to the nearest 0.1 mg.
    6.5.2  Add the assayed reference material:
    6.5.2.1  Liquids--Using a 100-[mu]L syringe, immediately add two or 
more drops of assayed reference material to the flask, then reweigh. Be 
sure that the drops fall directly into the alcohol without contacting 
the neck of the flask.
    6.5.2.2  Gases--To prepare standards for any of the four halocarbons 
that boil below 30  deg.C (bromomethane, chloroethane, chloromethane, 
and vinyl chloride), fill a 5-mL valved gas-tight syringe with the 
reference standard to the 5.0-mL mark. Lower the needle to 5 mm above 
the methanol meniscus. Slowly introduce the reference standard above the 
surface of the liquid (the heavy gas will rapidly dissolve in the 
methanol).
    6.5.3  Reweigh, dilute to volume, stopper, then mix by inverting the 
flask several times. Calculate the concentration in [mu]g/[mu]L from the 
net gain in weight. When compound purity is assayed to be 96% or 
greater, the weight may be used without correction to calculate the 
concentration of the stock standard. Commercially prepared stock 
standards may be used at any concentration if they are certified by the 
manufacturer or by an independent source.
    6.5.4  Transfer the stock standard solution into a Teflon-sealed 
screw-cap bottle. Store, with minimal headspace, at -10 to -20  deg.C 
and protect from light.
    6.5.5  Prepare fresh standards weekly for the four gases and 2-
chloroethylvinyl ether. All other standards must be replaced after one 
month, or sooner if comparison with check standards indicates a problem.
    6.6  Secondary dilution standards--Using stock solutions, prepare 
secondary dilution standards in methanol that contain the compounds of 
interest, either singly or mixed together. The secondary dilution 
standards should be prepared at concentrations such that the aqueous 
calibration standards prepared in Section 7.3 will bracket the working 
range of the analytical system. Secondary dilution standards should be 
stored with minimal headspace and should be checked frequently for signs 
of degradation or evaporation, especially just prior to preparing 
calibration standards from them.
    6.7  Surrogate standard spiking solution--Select a minimum of three 
surrogate compounds from Table 3. Prepare stock standard solutions for 
each surrogate standard in methanol as described in Section 6.5. Prepare 
a surrogate standard spiking solution from these stock standards at a 
concentration of 15 [mu]g/mL in water. Store the solutions at 4  deg.C 
in Teflon-sealed glass containers with a minimum of headspace. The 
solutions should be checked frequently for stability. The addition of 10 
[mu]L of this solution of 5 mL of sample or standard is equivalent to a 
concentration of 30 [mu]g/L of each surrogate standard.
    6.8  BFB Standard--Prepare a 25 [mu]g/mL solution of BFB in 
methanol.
    6.9  Quality control check sample concentrate--See Section 8.2.1.

                             7. Calibration

    7.1  Assemble a purge and trap system that meets the specifications 
in Section 5.2. Condition the trap overnight at 180  deg.C by 
backflushing with an inert gas flow of at least 20 mL/min. Condition the 
trap for 10 min once daily prior to use.
    7.2  Connect the purge and trap system to a gas chromatograph. The 
gas chromatograph must be operated using temperature and flow rate 
conditions equivalent to those given in Table 1.
    7.3  Internal standard calibration procedure--To use this approach, 
the analyst must select three or more internal standards that are 
similar in analytical behavior to the compounds of interest. The analyst 
must further demonstrate that the measurement of the internal standard 
is not affected by method or matrix interferences. Some recommended 
internal standards are listed in Table 3.
    7.3.1  Prepare calibration standards at a minimum of three 
concentration levels for each parameter by carefully adding 20.0 [mu]L 
of one or more secondary dilution standards to 50, 250, or 500 mL of 
reagent water. A 25-[mu]L syringe with a 0.006 in. ID needle should be 
used for this operation. One of the calibration standards should be at a 
concentration near, but above, the MDL (Table 1) and the other 
concentrations should correspond to the expected range of concentrations 
found in real samples or should define the working range of the GC/MS 
system. These aqueous standards can be stored up to 24 h, if held in 
sealed vials with zero headspace as described in Section 9.2. If not so 
stored, they must be discarded after 1 h.
    7.3.2  Prepare a spiking solution containing each of the internal 
standards using the procedures described in Sections 6.5 and

[[Page 190]]

6.6. It is recommended that the secondary dilution standard be prepared 
at a concentration of 15 [mu]g/mL of each internal standard compound. 
The addition of 10 [mu]L of this standard to 5.0 mL of sample or 
calibration standard would be equivalent to 30 [mu]g/L.
    7.3.3  Analyze each calibration standard according to Section 11, 
adding 10 [mu]L of internal standard spiking solution directly to the 
syringe (Section 11.4). Tabulate the area response of the characteristic 
m/z against concentration for each compound and internal standard, and 
calculate response factors (RF) for each compound using Equation 1.
[GRAPHIC] [TIFF OMITTED] TC15NO91.124

                                                              Equation 1

where:
As=Area of the characteristic m/z for the parameter to be 
measured.
Ais=Area of the characteristic m/z for the inernal standard.
Cis=Concentration of the internal standard.
Cs=Concentration of the parameter to be measured.

If the RF value over the working range is a constant (<35% RSD), the RF 
can be assumed to be invariant and the average RF can be used for 
calculations. Alternatively, the results can be used to plot a 
calibration curve of response ratios, As/Ais, vs. 
RF.
    7.4  The working calibration curve or RF must be verified on each 
working day by the measurement of a QC check sample.
    7.4.1  Prepare the QC check sample as described in Section 8.2.2.
    7.4.2  Analyze the QC check sample according to the method beginning 
in Section 10.
    7.4.3  For each parameter, compare the response (Q) with the 
corresponding calibration acceptance criteria found in Table 5. If the 
responses for all parameters of interest fall within the designated 
ranges, analysis of actual samples can begin. If any individual Q falls 
outside the range, proceed according to Section 7.4.4.
    Note: The large number of parameters in Table 5 present a 
substantial probability that one or more will not meet the calibration 
acceptance criteria when all parameters are analyzed.
    7.4.4  Repeat the test only for those parameters that failed to meet 
the calibration acceptance criteria. If the response for a parameter 
does not fall within the range in this second test, a new calibration 
curve or RF must be prepared for that parameter according to Section 
7.3.

                           8. Quality Control

    8.1  Each laboratory that uses this method is required to operate a 
formal quality control program. The minimum requirements of this program 
consist of an initial demonstration of laboratory capability and an 
ongoing analysis of spiked samples to evaluate and document data 
quality. The laboratory must maintain records to document the quality of 
data that is generated. Ongoing data quality checks are compared with 
established performance criteria to determine if the results of analyses 
meet the performance characteristics of the method. When results of 
sample spikes indicate atypical method performance, a quality control 
check standard must be analyzed to confirm that the measurements were 
performed in an in-control mode of operation.
    8.1.1  The analyst must make an initial, one-time, demonstration of 
the ability to generate acceptable accuracy and precision with this 
method. This ability is established as described in Section 8.2.
    8.1.2  In recognition of advances that are occurring in 
chromatography, the analyst is permitted certain options (detailed in 
Section 11.1) to improve the separations or lower the cost of 
measurements. Each time such a modification is made to the method, the 
analyst is required to repeat the procedure in Section 8.2.
    8.1.3  Each day, the analyst must analyze a reagent water blank to 
demonstrate that interferences from the analytical system are under 
control.
    8.1.4  The laboratory must, on an ongoing basis, spike and analyze a 
minimum of 5% of all samples to monitor and evaluate laboratory data 
quality. This procedure is described in Section 8.3.
    8.1.5  The laboratory must, on an ongoing basis, demonstrate through 
the analyses of quality control check standards that the operation of 
the measurement system is in control. This procedure is described in 
Section 8.4. The frequency of the check standard analyses is equivalent 
to 5% of all samples analyzed but may be reduced if spike recoveries 
from samples (Section 8.3) meet all specified quality control criteria.
    8.1.6  The laboratory must spike all samples with surrogate 
standards to monitor continuing laboratory performance. This procedure 
is described in Section 8.5.
    8.1.7  The laboratory must maintain performance records to document 
the quality of data that is generated. This procedure is described in 
Section 8.6.
    8.2  To establish the ability to generate acceptable accuracy and 
precision, the analyst must perform the following operations.
    8.2.1  A quality control (QC) check sample concentrate is required 
containing each parameter of interest at a concentration of 10 [mu]g/mL 
in methanol. The QC check sample concentrate must be obtained from the 
U.S. Environmental Protection Agency, Environmental Monitoring and 
Support Laboratory in Cincinnati, Ohio, if available. If not available 
from that source, the QC check sample

[[Page 191]]

concentrate must be obtained from another external source. If not 
available from either source above, the QC check sample concentrate must 
be prepared by the laboratory using stock standards prepared 
independently from those used for calibration.
    8.2.2  Prepare a QC check sample to contain 20 [mu]g/L of each 
parameter by adding 200 [mu]L of QC check sample concentrate to 100 mL 
of reagent water.
    8.2.3  Analyze four 5-mL aliquots of the well-mixed QC check sample 
according to the method beginning in Section 10.
    8.2.4  Calculate the average recovery (X) in [mu]g/L, and the 
standard deviation of the recovery (s) in [mu]g/L, for each parameter of 
interest using the four results.
    8.2.5  For each parameter compare s and X with the corresponding 
acceptance criteria for precision and accuracy, respectively, found in 
Table 5. If s and X for all parameters of interest meet the acceptance 
criteria, the system performance is acceptable and analysis of actual 
samples can begin. If any individual s exceeds the precision limit or 
any individual X falls outside the range for accuracy, the system 
performance is unacceptable for that parameter.
    Note: The large number of parameters in Table 5 present a 
substantial probability that one or more will fail at least one of the 
acceptance criteria when all parameters are analyzed.
    8.2.6  When one or more of the parameters tested fail at least one 
of the acceptance criteria, the analyst must proceed according to 
Section 8.2.6.1 or 8.2.6.2.
    8.2.6.1  Locate and correct the source of the problem and repeat the 
test for all parameters of interest beginning with Section 8.2.3.
    8.2.6.2  Beginning with Section 8.2.3, repeat the test only for 
those parameters that failed to meet criteria. Repeated failure, 
however, will confirm a general problem with the measurement system. If 
this occurs, locate and correct the source of the problem and repeat the 
test for all compounds of interest beginning with Section 8.2.3.
    8.3  The laboratory must, on an ongoing basis, spike at least 5% of 
the samples from each sample site being monitored to assess accuracy. 
For laboratories analyzing 1 to 20 samples per month, at least one 
spiked sample per month is required.
    8.3.1  The concentration of the spike in the sample should be 
determined as follows:
    8.3.1.1  If, as in compliance monitoring, the concentration of a 
specific parameter in the sample is being checked against a regulatory 
concentration limit, the spike should be at that limit or 1 to 5 times 
higher than the background concentration determined in Section 8.3.2, 
whichever concentration would be larger.
    8.3.1.2  If the concentration of a specific parameter in the sample 
is not being checked against a limit specific to that parameter, the 
spike should be at 20 [mu]g/L or 1 to 5 times higher than the background 
concentration determined in Section 8.3.2, whichever concentration would 
be larger.
    8.3.2  Analyze one 5-mL sample aliquot to determine the background 
concentration (B) of each parameter. If necessary, prepare a new QC 
check sample concentrate (Section 8.2.1) appropriate for the background 
concentrations in the sample. Spike a second 5-mL sample aliquot with 10 
[mu]L of the QC check sample concentrate and analyze it to determine the 
concentration after spiking (A) of each parameter. Calculate each 
percent recovery (P) as 100(A-B)%/T, where T is the known true value of 
the spike.
    8.3.3  Compare the percent recovery (P) for each parameter with the 
corresponding QC acceptance criteria found in Table 5. These acceptance 
criteria wer calculated to include an allowance for error in measurement 
of both the background and spike concentrations, assuming a spike to 
background ratio of 5:1. This error will be accounted for to the extent 
that the analyst's spike to background ratio approaches 5:1.7 
If spiking was performed at a concentration lower than 20 [mu]g/L, the 
analyst must use either the QC acceptance criteria in Table 5, or 
optional QC acceptance criteria calculated for the specific spike 
concentration. To calculate optional acceptance criteria for the 
recoveryof a parameter: (1) Calculate accuracy (X') using the equation 
in Table 6, substituting the spike concentration (T) for C; (2) 
calculate overall precision (S') using the equation in Table 6, 
substituting X' for X; (3) calculate the range for recovery at the spike 
concentration as (100 X'/T) (2.44(100 S'/T)%.7
    8.3.4  If any individual P falls outside the designated range for 
recovery, that parameter has failed the acceptance criteria. A check 
standard containing each parameter that failed the criteria must be 
analyzed as described in Section 8.4.
    8.4  If any parameter fails the acceptance criteria for recovery in 
Section 8.3, a QC check standard containing each parameter that failed 
must be prepared and analyzed.
    Note: The frequency for the required anlaysis of a QC check standard 
will depend upon the number of parameters being simultaneously tested, 
the complexity of the sample matrix, and the performance of the 
laboratory. If the entire list of parameters in Table 5 must be measured 
in the sample in Section 8.3, the probability that the analysis of a QC 
check standard will be required is high. In this case the QC check 
standard should be routinely analyzed with the spiked sample.
    8.4.1  Prepare the QC check standard by adding 10 [mu]L of QC check 
sample concentrate (Section 8.2.1 or 8.3.2) to 5 mL of reagent water. 
The QC check standard needs only to

[[Page 192]]

contain the parameters that failed criteria in the test in Section 8.3.
    8.4.2  Analyze the QC check standard to determine the concentration 
measured (A) of each parameter. Calculate each percent recovery 
(PS) as 100 (A/T)%, where T is the true value of the standard 
concentration.
    8.4.3  Compare the percent recovery (PS) for each 
parameter with the corresponding QC acceptance criteria found in Table 
5. Only parameters that failed the test in Section 8.3 need to be 
compared with these criteria. If the recovery of any such parameter 
falls outside the designated range, the laboratory performance for that 
parameter is judged to be out of control, and the problem must be 
immediately identified and corrected. The analytical result for that 
parameter in the unspiked sample is suspect and may not be reported for 
regulatory compliance purposes.
    8.5  As a quality control check, the laboratory must spike all 
samples with the surrogate standard spiking solutions as described in 
Section 11.4, and calculate the percent recovery of each surrogate 
compound.
    8.6  As part of the QC program for the laboratory, method accuracy 
for wastewater samples must be assessed and records must be maintained. 
After the analysis of five spiked wastewater samples as in Section 8.3, 
calculate the average percent recovery (P) and the standard deviation of 
the percent recovery (sp). Express the accuracy assessment as 
a percent recovery interval from P--2sp to P + 
2sp. If P=90% and sp=10%, for example, the 
accuracy interval is expressed as 70-110%. Update the accuracy 
assessment for each parameter a regular basis (e.g. after each five to 
ten new accuracy measurements).
    8.7  It is recommended that the laboratory adopt additional quality 
assurance practices for use with this method. The specific practices 
that are most productive depend upon the needs of the laboratory and the 
nature of the samples. Field duplicates may be analyzed to assess the 
precision of the environmental measurements. Whenever possible, the 
laboratory should analyze standard reference materials and participate 
in relevant performance evaluation studies.

            9. Sample Collection, Preservation, and Handling

    9.1  All samples must be iced or refrigerated from the time of 
collection until analysis. If the sample contains residual chlorine, add 
sodium thiosulfate preservative (10 mg/40 mL is sufficient for up to 5 
ppm Cl2) to the empty sample bottle just prior to shipping to 
the sampling site. EPA Methods 330.4 and 330.5 may be used for 
measurement of residual chlorine.\8\ Field test kits are available for 
this purpose.
    9.2  Grab samples must be collected in glass containers having a 
total volume of at least 25 mL. Fill the sample bottle just to 
overflowing in such a manner that no air bubbles pass through the sample 
as the bottle is being filled. Seal the bottle so that no air bubbles 
are entrapped in it. If preservative has been added, shake vigorously 
for 1 min. Maintain the hermetic seal on the sample bottle until time of 
analysis.
    9.3  Experimental evidence indicates that some aromatic compounds, 
notably benzene, toluene, and ethyl benzene are susceptible to rapid 
biological degradation under certain environmental conditions.\3\ 
Refrigeration alone may not be adequate to preserve these compounds in 
wastewaters for more than seven days. For this reason, a separate sample 
should be collected, acidified, and analyzed when these aromatics are to 
be determined. Collect about 500 mL of sample in a clean container. 
Adjust the pH of the sample to about 2 by adding 1+1 HCl while stirring 
vigorously, Check pH with narrow range (1.4 to 2.8) pH paper. Fill a 
sample container as described in Section 9.2.
    9.4  All samples must be analyzed within 14 days of collection.\3\

                    10. Daily GC/MS Performance Tests

    10.1  At the beginning of each day that analyses are to be 
performed, the GC/MS system must be checked to see if acceptable 
performance criteria are achieved for BFB.\9\ The performance test must 
be passed before any samples, blanks, or standards are analyzed, unless 
the instrument has met the DFTPP test described in Method 625 earlier in 
the day.\10\
    10.2  These performance tests require the following instrumental 
parameters:

    Electron Energy: 70 V (nominal)
    Mass Range: 20 to 260 amu
    Scan Time: To give at least 5 scans per peak but not to exceed 7 s 
per scan.

    10.3  At the beginning of each day, inject 2 [mu]L of BFB solution 
directly on the column. Alternatively, add 2 [mu]L of BFB solution to 
5.0 mL of reagent water or standard solution and analyze the solution 
according to section 11. Obtain a background-corrected mass spectrum of 
BFB and confirm that all the key m/z criteria in Table 2 are achieved. 
If all the criteria are not achieved, the analyst must retune the mass 
spectrometer and repeat the test until all criteria are achieved.

                11. Sample Purging and Gas Chromatography

    11.1  Table 1 summarizes the recommended operating conditions for 
the gas chromatograph. Included in this table are retention times and 
MDL that can be achieved under these conditions. An example of the 
separations achieved by this column is shown in Figure 5. Other packed 
columns or chromatographic conditions may be used if the requirements of 
Section 8.2 are met.

[[Page 193]]

    11.2  After achieving the key m/z abundance criteria in Section 10, 
calibrate the system daiy as described in Section 7.
    11.3  Adjust the purge gas (helium) flow rate to 40 mL/min. Attach 
the trap inlet to the purging device, and set the purge and trap system 
to purge (Figure 3). Open the syringe valve located on the purging 
device sample introduction needle.
    11.4  Allow the sample to come to ambient temperature prior to 
introducing it into the syringe. Remove the plunger from a 5-mL syringe 
and attach a closed syringe valve. Open the sample bottle (or standard) 
and carefully pour the sample into the syringe barrel to just short of 
overflowing. Replace the syringe plunger and compress the sample. Open 
the syringe valve and vent any residual air while adjusting the sample 
volume to 5.0 mL. Since this process of taking an aliquot destroys the 
validity of the sample for future analysis, the analyst should fill a 
second syringe at this time to protect against possible loss of data. 
Add 10.0 [mu]L of the surrogate spiking solution (Section 6.7) and 10.0 
[mu]L of the internal standard spiking solution (Section 7.3.2) through 
the valve bore, then close the valve. The surrogate and internal 
standards may be mixed and added as a single spiking solution.
    11.5  Attach the syringe-syringe valve assembly to the syringe valve 
on the purging device. Open the syringe valves and inject the sample 
into the purging chamber.
    11.6  Close both valves and purge the sample for 11.00.1 
min at ambient temperature.
    11.7  After the 11-min purge time, attach the trap to the 
chromatograph, adjust the purge and trap system to the desorb mode 
(Figure 4), and begin to temperature program the gas chromatograph. 
Introduce the trapped materials to the GC column by rapidly heating the 
trap to 180  deg.C while backflushing the trap with an inert gas between 
20 and 60 mL/min for 4 min. If rapid heating of the trap cannot be 
achieved, the GC cloumn must be used as a secondary trap by cooling it 
to 30  deg.C (subambient temperature, if problems persist) instead of 
the initial program temperature of 45  deg.C.
    11.8  While the trap is being desorbed into the gas chromatograph, 
empty the purging chamber using the sample introduction syringe. Wash 
the chamber with two 5-mL flushes of reagent water.
    11.9  After desorbing the sample for 4 min, recondition the trap by 
returning the purge and trap system to the purge mode. Wait 15 s then 
close the syringe valve on the purging device to begin gas flow through 
the trap. The trap temperature should be maintained at 180  deg.C. After 
approximately 7 min, turn off the trap heater and open the syringe valve 
to stop the gas flow through the trap. When the trap is cool, the next 
sample can be analyzed.
    11.10  If the response for any m/z exceeds the working range of the 
system, prepare a dilution of the sample with reagent water from the 
aliquot in the second syringe and reanalyze.

                     12. Qualitative Identification

    12.1  Obtain EICPs for the primary m/z (Table 4) and at least two 
secondary masses for each parameter of interest. The following criteria 
must be met to make a qualitative identification:
    12.1.1  The characteristic masses of each parameter of interest must 
maximize in the same or within one scan of each other.
    12.1.2  The retention time must fall within 30 s of the 
retention time of the authentic compound.
    12.1.3  The relative peak heights of the three characteristic masses 
in the EICPs must fall within 20% of the relative 
intensities of these masses in a reference mass spectrum. The reference 
mass spectrum can be obtained from a standard analyzed in the GC/MS 
system or from a reference library.
    12.2  Structural isomers that have very similar mass spectra and 
less than 30 s difference in retention time, can be explicitly 
identified only if the resolution between authentic isomers in a 
standard mix is acceptable. Acceptable resolution is achieved if the 
baseline to valley height between the isomers is less than 25% of the 
sum of the two peak heights. Otherwise, structural isomers are 
identified as isomeric pairs.

                            13. Calculations

    13.1  When a parameter has been identified, the quantitation of that 
parameter should be based on the integrated abundance from the EICP of 
the primary characteristic m/z given in Table 4. If the sample produces 
an interference for the primary m/z, use a secondary characteristic m/z 
to quantitate.
    Calculate the concentration in the sample using the response factor 
(RF) determined in Section 7.3.3 and Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.125

                                                              Equation 2

where:
AS=Area of the characteristic m/z for the parameter or 
surrogate standard to be measured.
Ais=Area of the characteristic m/z for the internal standard.
Cis=Concentration of the internal standard.

    13.2  Report results in [mu]g/L without correction for recovery 
data. All QC data obtained should be reported with the sample results.

[[Page 194]]

                         14. Method Performance

    14.1  The method detection limit (MDL) is defined as the minimum 
concentration of a substance that can be measured and reported with 99% 
confidence that the value is above zero.\1\ The MDL concentrations 
listed in Table 1 were obtained using reagent water.\11\ Similar results 
were achieved using representative wastewaters. The MDL actually 
achieved in a given analysis will vary depending on instrument 
sensitivity and matrix effects.
    14.2  This method was tested by 15 laboratories using reagent water, 
drinking water, surface water, and industrial wastewaters spiked at six 
concentrations over the range 5-600 [mu]g/L.12Single operator 
precision, overall precision, and method accuracy were found to be 
directly related to the concentration of the parameter and essentially 
independent of the sample matrix. Linear equations to describe these 
relationships are presented in Table 5.

                               References

    1. 40 CFR part 136, appendix B.
    2. Bellar, T.A., and Lichtenberg, J.J. ``Determining Volatile 
Organics at Microgram-per-Litre Levels by Gas Chromatography,'' Journal 
American Water Works Association, 66, 739 (1974).
    3. Bellar, T.A., and Lichtenberg, J.J. ``Semi-Automated Headspace 
Analysis of Drinking Waters and Industrial Waters for Purgeable Volatile 
Organic Compounds, '' Measurement of Organic Pollutants in Water and 
Wastewater, C.E. Van Hall, editor, American Society for Testing and 
Materials, Philadelphia, PA. Special Technical Publication 686, 1978.
    4. ``Carcinogens--Working With Carcinogens,'' Department of Health, 
Education, and Welfare, Public Health Service, Center for Disease 
Control, National Institute for Occupational Safety and Health, 
Publication No. 77-206, August 1977.
    5. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR 
part 1910), Occupational Safety and Health Administration, OSHA 2206 
(Revised, January 1976).
    6. ``Safety in Academic Chemistry Laboratories,'' American Chemical 
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
    7. Provost, L.P., and Elder, R.S. ``Interpretation of Percent 
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44 
used in the equation in Section 8.2.3 is two times the value 1.22 
derived in this report.)
    8. ``Methods 330.4 (Titrimetric, DPD-FAS) and 330.5 
(Spectrophotometric, DPD) for Chlorine, Total Residual,'' Methods for 
Chemical Analysis of Water and Wastes, EPA-600/4-79-020, U.S. 
Environmental Protection Agency, Environmental Monitoring and Support 
Laboratory, Cincinnati, Ohio 45268, March 1979.
    9. Budde, W.L., and Eichelberger, J.W. ``Performance Tests for the 
Evaluation of Computerized Eas Chromatography/Mass Spectrometry 
Equipment and Laboratories,'' EPA-600/4-80-025, U.S. Environmental 
Protection Agency, Environmental Monitoring and Support Laboratory, 
Cincinnati, Ohio 45268, April 1980.
    10. Eichelberger, J.W., Harris, L.E., and Budde, W.L. ``Reference 
Compound to Calibrate Ion Abundance Measurement in Gas Chromatography--
Mass Spectrometry Systems,'' Analytical Chemistry, 47, 995-1000 (1975).
    11. ``Method Detection Limit for Methods 624 and 625,'' Olynyk, P., 
Budde, W.L., and Eichelberger, J.W. Unpublished report, May 14, 1980.
    12. ``EPA Method Study 29 EPA Method 624--Purgeables,'' EPA 600/4-
84-054, National Technical Information Service, PB84-209915, 
Springfield, Virginia 22161, June 1984.
    13.``Method Performance Data for Method 624,'' Memorandum from R. 
Slater and T. Pressley, U.S. Environmental Protection Agency, 
Environmental Monitoring and Support Laboratory, Cincinnati, Ohio 45268, 
January 17, 1984.

     Table 1--Chromatographic Conditions and Method Detection Limits
------------------------------------------------------------------------
                                                                Method
                                                   Retention   detection
                    Parameter                     time (min)     limit
                                                               ([mu]g/L)
------------------------------------------------------------------------
Chloromethane...................................         2.3          nd
Bromomethane....................................         3.1          nd
Vinyl chloride..................................         3.8          nd
Chloroethane....................................         4.6          nd
Methylene chloride..............................         6.4         2.8
Trichlorofluoromethane..........................         8.3          nd
1,1-Dichloroethene..............................         9.0         2.8
1,1-Dichloroethane..............................        10.1         4.7
trans-1,2-Dichloroethene........................        10.8         1.6
Chloroform......................................        11.4         1.6
1,2-Dichloroethane..............................        12.1         2.8
1,1,1-Trichloroethane...........................        13.4         3.8
Carbon tetrachloride............................        13.7         2.8
Bromodichloromethane............................        14.3         2.2
1,2-Dichloroproane..............................        15.7         6.0
cis-1,3-Dichloropropene.........................        15.9         5.0
Trichloroethene.................................        16.5         1.9
Benzene.........................................        17.0         4.4
Dibromochloromethane............................        17.1         3.1
1,1,2-Trichloroethane...........................        17.2         5.0
trans-1,3-Dichloropropene.......................        17.2          nd
2-Chloroethylvinlyl ether.......................        18.6          nd
Bromoform.......................................        19.8         4.7
1,1,2,2-Tetrachloroethane.......................        22.1         6.9
Tetrachloroethene...............................        22.2         4.1
Toluene.........................................        23.5         6.0
Chlorobenzene...................................        24.6         6.0
Ethyl benzene...................................        26.4         7.2
1,3-Dichlorobenzene.............................        33.9          nd
1,2-Dichlorobenzene.............................        35.0          nd

[[Page 195]]

 
1,4-Dichlorobenzene.............................        35.4          nd
------------------------------------------------------------------------
Column conditions: Carbopak B (60/80 mesh) coated with 1% SP-1000 packed
  in a 6 ft by 0.1 in. ID glass column with helium carrier gas at 30 mL/
  min. flow rate. Column temperature held at 45 deg.C for 3 min., then
  programmed at 8 deg.C/min. to 220 deg.C and held for 15 min.
nd=not determined.


                 Table 2--BFB Key m/z Abundance Criteria
------------------------------------------------------------------------
                   Mass                        m/z Abundance criteria
------------------------------------------------------------------------
50........................................  15 to 40% of mass 95.
75........................................  30 to 60% of mass 95.
95........................................  Base Peak, 100% Relative
                                             Abundance.
96........................................  5 to 9% of mass 95.
173.......................................  <2% of mass 174.
174.......................................  50% of mass 95.
175.......................................  5 to 9% of mass 174.
176.......................................  95% but <101% of
                                             mass 174.
177.......................................  5 to 9% of mass 176.
------------------------------------------------------------------------


           Table 3--Suggested Surrogate and Internal Standards
------------------------------------------------------------------------
                                         Retention
                Compound                    time    Primary   Secondary
                                           (min)a     m/z       masses
------------------------------------------------------------------------
Benzene d-6............................     17.0        84   ...........
4-Bromofluorobenzene...................     28.3        95      174, 176
1,2-Dichloroethane d-4.................     12.1       102   ...........
1,4-Difluorobenzene....................     19.6       114        63, 88
Ethylbenzene d-5.......................     26.4       111   ...........
Ethylbenzene d-10......................     26.4        98   ...........
Fluorobenzene..........................     18.4        96            70
Pentafluorobenzene.....................     23.5       168   ...........
Bromochloromethane.....................      9.3       128   49, 130, 51
2-Bromo-1-chloropropane................     19.2        77       79, 156
1, 4-Dichlorobutane....................     25.8        55        90, 92
------------------------------------------------------------------------
a For chromatographic conditions, see Table 1.


        Table 4mdash;Characteristic Masses for Purgeable Organics
------------------------------------------------------------------------
              Parameter                Primary          Secondary
------------------------------------------------------------------------
Chloromethane........................      50   52.
Bromomethane.........................      94   96.
Vinyl chloride.......................      62   64.
Chloroethane.........................      64   66.
Methylene chloride...................      84   49, 51, and 86.
Trichlorofluoromethane...............     101   103.
1,1-Dichloroethene...................      96   61 and 98.
1,1-Dichloroethane...................      63   65, 83, 85, 98, and 100.
trans-1,2-Dichloroethene.............      96   61 and 98.
Chloroform...........................      83   85.
1,2-Dichloroethane...................      98   62, 64, and 100.
1,1,1-Trichloroethane................      97   99, 117, and 119.
Carbon tetrachloride.................     117   119 and 121.
Bromodichloromethane.................     127   83, 85, and 129.
1,2-Dichloropropane..................     112   63, 65, and 114.
trans-1,3-Dichloropropene............      75   77.
Trichloroethene......................     130   95, 97, and 132.
Benzene..............................      78   ........................
Dibromochloromethane.................     127   129, 208, and 206.
1,1,2-Trichloroethane................      97   83, 85, 99, 132, and
                                                 134.
cis-1,3-Dichloropropene..............      75   77.
2-Chloroethylvinyl ether.............     106   63 and 65.
Bromoform............................     173   171, 175, 250, 252, 254,
                                                 and 256.
1,1,2,2-Tetrachloroethane............     168   83, 85, 131, 133, and
                                                 166.
Tetrachloroethene....................     164   129, 131, and 166.
Toluene..............................      92   91.
Chlorobenzene........................     112   114.
Ethyl benzene........................     106   91.
1,3-Dichlorobenzene..................     146   148 and 113.
1,2-Dichlorobenzene..................     146   148 and 113.
1,4-Dichlorobenzene..................     146   148 and 113.
------------------------------------------------------------------------


                          Table 5--Calibration and QC Acceptance Criteria--Method 624a
----------------------------------------------------------------------------------------------------------------
                                                                          Limit
                                                          Range for Q     for s     Range for X    Range for P,
                       Parameter                          ([mu]/g/L)    ([mu]/g/    ([mu]/g/L)        Ps (%)
                                                                           L)
----------------------------------------------------------------------------------------------------------------
Benzene...............................................       12.8-27.2       6.9       15.2-26.0          37-151
Bromodichloromethane..................................       13.1-26.9       6.4       10.1-28.0          35-155
Bromoform.............................................       14.2-25.8       5.4       11.4-31.1          45-169
Bromomethane..........................................        2.8-37.2      17.9          D-41.2           D-242
Carbon tetrachloride..................................       14.6-25.4       5.2       17.2-23.5          70-140
Chlorobenzene.........................................       13.2-26.8       6.3       16.4-27.4          37-160
Chloroethane..........................................        7.6-32.4      11.4        8.4-40.4          14-230
2-Chloroethylvinyl ether..............................          D-44.8      25.9          D-50.4           D-305
Chloroform............................................       13.5-26.5       6.1       13.7-24.2          51-138
Chloromethane.........................................          D-40.8      19.8          D-45.9           D-273
Dibromochloromethane..................................       13.5-26.5       6.1       13.8-26.6          53-149
1,2-Dichlorobenzene...................................       12.6-27.4       7.1       11.8-34.7          18-190
1,3-Dichlorobenzene...................................       14.6-25.4       5.5       17.0-28.8          59-156
1,4-Dichlorobenzene...................................       12.6-27.4       7.1       11.8-34.7          18-190
1,1-Dichloroethane....................................       14.5-25.5       5.1       14.2-28.5          59-155
1,2-Dichloroethane....................................       13.6-26.4       6.0       14.3-27.4          49-155
1,1-Dichlorothene.....................................       10.1-29.9       9.1        3.7-42.3           D-234
trans-1,2-Dichloroethene..............................       13.9-26.1       5.7       13.6-28.5          54-156

[[Page 196]]

 
1,2-Dichloropropane...................................        6.8-33.2      13.8        3.8-36.2           D-210
cis-1,3-Dichloropropene...............................        4.8-35.2      15.8        1.0-39.0           D-227
trans-1,3-Dichloropropene.............................       10.0-30.0      10.4        7.6-32.4          17-183
Ethyl benzene.........................................       11.8-28.2       7.5       17.4-26.7          37-162
Methylene chloride....................................       12.1-27.9       7.4          D-41.0           D-221
1,1,2,2-Tetrachloroethane.............................       12.1-27.9       7.4       13.5-27.2          46-157
Tetrachloroethene.....................................       14.7-25.3       5.0       17.0-26.6          64-148
Toluene...............................................       14.9-25.1       4.8       16.6-26.7          47-150
1,1,1-Trichloroethane.................................       15.0-25.0       4.6       13.7-30.1          52-162
1,1,2-Trichloroethane.................................       14.2-25.8       5.5       14.3-27.1          52-150
Trichloroethene.......................................       13.3-26.7       6.6       18.6-27.6          71-157
Trichlorofluoromethane................................        9.6-30.4      10.0        8.9-31.5          17-181
Vinyl chloride........................................        0.8-39.2      20.0          D-43.5           D-251
----------------------------------------------------------------------------------------------------------------
Q= Concentration measured in QC check sample, in [mu]g/L (Section 7.5.3).
s= Standard deviation of four recovery measurements, in [mu]g/L (Section 8.2.4).
X= Average recovery of four recovery measurements, in [mu]g/L (Section 8.2.4).
P, Ps= Percent recovery measured, (Section 8.3.2, Section 8.4.2).
D= Detected; result must be greater than zero.
a Criteria were calculated assuming a QC check sample concentration of 20 [mu]g/L.
 
Note: These criteria are based directly upon the method performance data in Table 6. Where necessary, the limits
  for recovery have been broadened to assure applicability of the limits to concentrations below those used to
  develop Table 6.


                Table 6--Method Accuracy and Precision as Functions of Concentration--Method 624
----------------------------------------------------------------------------------------------------------------
                                                                      Single analyst
               Parameter                 Accuracy, as recovery,  precision, sr  Overall precision, S ([mu]g/L)          ([mu]g/L)            iden-2> ([mu]g/L)
----------------------------------------------------------------------------------------------------------------
Benzene...............................  0.93C+2.00               0.26X-1.74               0.25X-1.33
Bromodichloromethane..................  1.03C-1.58               0.15X+0.59               0.20X+1.13
Bromoform.............................  1.18C-2.35               0.12X+0.36               0.17X+1.38
Bromomethane a........................  1.00C                    0.43X                    0.58X
Carbon tetrachloride..................  1.10C-1.68               0.12X+0.25               0.11X+0.37
Chlorobenzene.........................  0.98C+2.28               0.16X-0.09               0.26X-1.92
Chloroethane..........................  1.18C+0.81               0.14X+2.78               0.29X+1.75
2-Chloroethylvinyl ether a............  1.00C                    0.62X                    0.84X
Chloroform............................  0.93C+0.33               0.16X+0.22               0.18X+0.16
Chloromethane.........................  1.03C+0.81               0.37X+2.14               0.58X+0.43
Dibromochloromethane..................  1.01C-0.03               0.17X-0.18               0.17X+0.49
1,2-Dichlorobenzene b.................  0.94C+4.47               0.22X-1.45               0.30X-1.20
1,3-Dichlorobenzene...................  1.06C+1.68               0.14X-0.48               0.18X-0.82
1,4-Dichlorobenzene b.................  0.94C+4.47               0.22X-1.45               0.30X-1.20
1,1-Dichloroethane....................  1.05C+0.36               0.13X-0.05               0.16X+0.47
1,2-Dichloroethane....................  1.02C+0.45               0.17X-0.32               0.21X-0.38
1,1-Dichloroethene....................  1.12C+0.61               0.17X+1.06               0.43X-0.22
trans-1,2,-Dichloroethene.............  1.05C+0.03               0.14X+0.09               0.19X+0.17
1,2-Dichloropropane a.................  1.00C                    0.33X                    0.45X
cis-1,3-Dichloropropene a.............  1.00C                    0.38X                    0.52X
trans-1,3-Dichloropropene a...........  1.00C                    0.25X                    0.34X
Ethyl benzene.........................  0.98C+2.48               0.14X+1.00               0.26X-1.72
Methylene chloride....................  0.87C+1.88               0.15X+1.07               0.32X+4.00
1,1,2,2-Tetrachloroethane.............  0.93C+1.76               0.16X+0.69               0.20X+0.41
Tetrachloroethene.....................  1.06C+0.60               0.13X-0.18               0.16X-0.45
Toluene...............................  0.98C+2.03               0.15X-0.71               0.22X-1.71
1,1,1-Trichloroethane.................  1.06C+0.73               0.12X-0.15               0.21X-0.39
1,1,2-Trichloroethane.................  0.95C+1.71               0.14X+0.02               0.18X+0.00
Trichloroethene.......................  1.04C+2.27               0.13X+0.36               0.12X+0.59
Trichloroflouromethane................  0.99C+0.39               0.33X-1.48               0.34X-0.39
Vinyl chloride........................  1.00C                    0.48X                    0.65X
----------------------------------------------------------------------------------------------------------------
X=Expected recovery for one or more measurements of a sample containing a concentration of C, in [mu]g/
  L.
Sr=Expected single analyst standard deviation of measurements at an average concentration found ofX, in [mu]g/L.
S=Expected interlaboratory standard deviation of measurements at an average concentration found ofX,
  in [mu]g/L.
C=True value for the concentration, in [mu]g/L.
X=Average recovery found for measurements of samples containing a concentration of C, in [mu]g/L.
a Estimates based upon the performance in a single laboratory.13
b Due to chromatographic resolution problems, performance statements for these isomers are based upon the sums
  of their concentrations.


[[Page 197]]

[GRAPHIC] [TIFF OMITTED] TC02JY92.038


[[Page 198]]

[GRAPHIC] [TIFF OMITTED] TC02JY92.039


[[Page 199]]

[GRAPHIC] [TIFF OMITTED] TC02JY92.040


[[Page 200]]

[GRAPHIC] [TIFF OMITTED] TC02JY92.041

                   Method 625--Base/Neutrals and Acids

                        1. Scope and Application

    1.1  This method covers the determination of a number of organic 
compounds that are partitioned into an organic solvent and are amenable 
to gas chromatography. The parameters listed in Tables 1 and 2 may be 
qualitatively and quantitatively determined using this method.
    1.2  The method may be extended to include the parameters listed in 
Table 3. Benzidine can be subject to oxidative losses during solvent 
concentration. Under the alkaline conditions of the extraction step, 
[alpha]-BHC, [gamma]-BHC, endosulfan I and II, and endrin are subject to 
decomposition. Hexachlorocyclopentadiene is subject to thermal 
decomposition in the inlet of the gas chromatograph, chemical reaction 
in acetone solution, and photochemical decomposition. N-
nitrosodimethylamine is difficult to separate from the solvent under the 
chromatographic conditions described. N-nitrosodiphenylamine decomposes 
in the gas chromatographic inlet and cannot be separated from 
diphenylamine. The preferred method for each of these parameters is 
listed in Table 3.
    1.3  This is a gas chromatographic/mass spectrometry (GC/MS) method 
2,14 applicable to the determination of the compounds listed 
in Tables 1, 2, and 3 in municipal and industrial discharges as provided 
under 40 CFR 136.1.

[[Page 201]]

    1.4  The method detection limit (MDL, defined in Section 16.1) \1\ 
for each parameter is listed in Tables 4 and 5. The MDL for a specific 
wastewater may differ from those listed, depending upon the nature of 
interferences in the sample matrix.
    1.5  Any modification to this method, beyond those expressly 
permitted, shall be considered as a major modification subject to 
application and approval of alternate test procedures under 40 CFR 136.4 
and 136.5. Depending upon the nature of the modification and the extent 
of intended use, the applicant may be required to demonstrate that the 
modifications will produce equivalent results when applied to relevant 
wastewaters.
    1.6  This method is restricted to use by or under the supervision of 
analysts experienced in the use of a gas chromatograph/mass spectrometer 
and in the interpretation of mass spectra. Each analyst must demonstrate 
the ability to generate acceptable results with this method using the 
procedure described in Section 8.2.

                          2. Summary of Method

    2.1 A measured volume of sample, approximately 1-L, is serially 
extracted with methylene chloride at a pH greater than 11 and again at a 
pH less than 2 using a separatory funnel or a continuous extractor.\2\ 
The methylene chloride extract is dried, concentrated to a volume of 1 
mL, and analyzed by GC/MS. Qualitative identification of the parameters 
in the extract is performed using the retention time and the relative 
abundance of three characteristic masses (m/z). Quantitative analysis is 
performed using internal standard techniques with a single 
characteristic m/z.

                            3. Interferences

    3.1  Method interferences may be caused by contaminants in solvents, 
reagents, glassware, and other sample processing hardware that lead to 
discrete artifacts and/or elevated baselines in the total ion current 
profiles. All of these materials must be routinely demonstrated to be 
free from interferences under the conditions of the analysis by running 
laboratory reagent blanks as described in Section 8.1.3.
    3.1.1  Glassware must be scrupulously cleaned.3 Clean all 
glassware as soon as possible after use by rinsing with the last solvent 
used in it. Solvent rinsing should be followed by detergent washing with 
hot water, and rinses with tap water and distilled water. The glassware 
should then be drained dry, and heated in a muffle furnace at 400  deg.C 
for 15 to 30 min. Some thermally stable materials, such as PCBs, may not 
be eliminated by this treatment. Solvent rinses with acetone and 
pesticide quality hexane may be substituted for the muffle furnace 
heating. Thmrough rinsing with such solvents usually eliminates PCB 
interference. Volumetric ware should not be heated in a muffle furnace. 
After drying and cooling, glassware should be sealed and stored in a 
clean environment to prevent any accumulation of dust or other 
contaminants. Store inverted or capped with aluminum foil.
    3.1.2  The use of high purity reagents and solvents helps to 
minimize interference problems. Purification of solvents by distillation 
in all-glass systems may be required.
    3.2  Matrix interferences may be caused by contaminants that are co-
extracted from the sample. The extent of matrix interferences will vary 
considerably from source to source, depending upon the nature and 
diversity of the industrial complex or municipality being sampled.
    3.3  The base-neutral extraction may cause significantly reduced 
recovery of phenol, 2-methylphenol, and 2,4-dimethylphenol. The analyst 
must recognize that results obtained under these conditions are minimum 
concentrations.
    3.4  The packed gas chromatographic columns recommended for the 
basic fraction may not exhibit sufficient resolution for certain 
isomeric pairs including the following: anthracene and phenanthrene; 
chrysene and benzo(a)anthracene; and benzo(b)fluoranthene and 
benzo(k)fluoranthene. The gas chromatographic retention time and mass 
spectra for these pairs of compounds are not sufficiently different to 
make an unambiguous identification. Alternative techniques should be 
used to identify and quantify these specific compounds, such as Method 
610.
    3.5  In samples that contain an inordinate number of interferences, 
the use of chemical ionization (CI) mass spectrometry may make 
identification easier. Tables 6 and 7 give characteristic CI ions for 
most of the compounds covered by this method. The use of CI mass 
spectrometry to support electron ionization (EI) mass spectrometry is 
encouraged but not required.

                                4. Safety

    4.1  The toxicity or carcinogenicity of each reagent used in this 
method have not been precisely defined; however, each chemical compound 
should be treated as a potential health hazard. From this viewpoint, 
exposure to these chemicals must be reduced to the lowest possible level 
by whatever means available. The laboratory is responsible for 
maintaining a current awareness file of OSHA regulations regarding the 
safe handling of the chemicals specified in this method. A reference 
file of material data handling sheets should also be made available to 
all personnel involved in the chemical analysis. Additional references 
to laboratory safety are available and have been identified 
4-6 for the information of the analyst.

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    4.2  The following parameters covered by this method have been 
tentatively classified as known or suspected, human or mammalian 
carcinogens: benzo(a)anthracene, benzidine, 3,3'-dichlorobenzidine, 
benzo(a)pyrene, [alpha]-BHC, [beta]-BHC, [delta]-BHC, [gamma]-BHC, 
dibenzo(a,h)anthracene, N-nitrosodimethylamine, 4,4'-DDT, and 
polychlorinated biphenyls (PCBs). Primary standards of these toxic 
compounds should be prepared in a hood. A NIOSH/MESA approved toxic gas 
respirator should be worn when the analyst handles high concentrations 
of these toxic compounds.

                       5. Apparatus and Materials

    5.1  Sampling equipment, for discrete or composit sampling.
    5.1.1  Grab sample bottle--1-L or 1-gt, amber glass, fitted with a 
screw cap lined with Teflon. Foil may be substituted for Teflon if the 
sample is not corrosive. If amber bottles are not available, protect 
samples from light. The bottle and cap liner must be washed, rinsed with 
acetone or methylene chloride, and dried before use to minimize 
contamination.
    5.1.2  Automatic sampler (optional)--The sampler must incorporate 
glass sample containers for the collection of a minimum of 250 mL of 
sample. Sample containers must be kept refrigerated at 4  deg.C and 
protected from light during compositing. If the sampler uses a 
peristaltic pump, a minimum length of compressible silicone rubber 
tubing may be used. before use, however, the compressible tubing should 
be throughly rinsed with methanol, followed by repeated rinsings with 
distilled water to minimize the potential for contamination of the 
sample. An integrating flow meter is required to collect flow 
proportional composites.
    5.2  Glassware (All specifications are suggested. Catalog numbers 
are included for illustration only.):
    5.2.1  Separatory funnel--2-L, with Teflon stopcock.
    5.2.2  Drying column--Chromatographic column, 19 mm ID, with coarse 
frit
    5.2.3  Concentrator tube, Kuderna-Danish--10-mL, graduated (Kontes 
K-570050-1025 or equivalent). Calibration must be checked at the volumes 
employed in the test. Ground glass stopper is used to prevent 
evaporation of extracts.
    5.2.4  Evaporative flask, Kuderna-Danish--500-mL (Kontes K-57001-
0500 or equivalent). Attach to concentrator tube with springs.
    5.2.5  Snyder column, Kuderna-Danish--Three all macro (Kontes K-
503000-0121 or equivalent).
    5.2.6  Snyder column, Kuderna-Danish--Two-ball macro (Kontes K-
569001-0219 or equivalent).
    5.2.7  Vials--10 to 15-mL, amber glass, with Teflon-lined screw cap.
    5.2.8  Continuous liquid--liquid extractor--Equipped with Teflon or 
glass connecting joints and stopcocks requiring no lubrication. 
(Hershberg-Wolf Extractor, Ace Glass Company, Vineland, N.J., P/N 6841-
10 or equivalent.)
    5.3  Boiling chips--Approximately 10/40 mesh. Heat to 400  deg.C for 
30 min of Soxhlet extract with methylene chloride.
    5.4  Water bath--Heated, with concentric ring cover, capable of 
temperature control (2 deg.C). The bath should be used in a 
hood.
    5.5  Balance--Analytical, capable of accurately weighing 0.0001 g.
    5.6  GC/MS system:
    5.6.1  Gas Chromatograph--An analytical system complete with a 
temperature programmable gas chromatograph and all required accessores 
including syringes, analytical columns, and gases. The injection port 
must be designed for on-column injection when using packed columns and 
for splitless injection when using capillary columns.
    5.6.2  Column for base/neutrals--1.8 m long x 2 mm ID glass, packed 
with 3% SP-2250 on Supelcoport (100/120 mesh) or equivalent. This column 
was used to develop the method performance statements in Section 16. 
Guidelines for the use of alternate column packings are provided in 
Section 13.1.
    5.6.3  Column for acids--1.8 m long x 2 mm ID glass, packed with 1% 
SP-1240DA on Supelcoport (100/120 mesh) or equivalent. This column was 
used to develop the method performance statements in Section 16. 
Guidelines for the use of alternate column packings are given in Section 
13.1.
    5.6.4  Mass spectrometer--Capable of scanning from 35 to 450 amu 
every 7 s or less, utilizing a 70 V (nominal) electron energy in the 
electron impact ionization mode, and producing a mass spectrum which 
meets all the criteria in Table 9 when 50 ng of decafluorotriphenyl 
phosphine (DFTPP; bis(perfluorophenyl) phenyl phosphine) is injected 
through the GC inlet.
    5.6.5  GC/MS interface--Any GC to MS interface that gives acceptable 
calibration points at 50 ng per injection for each of the parameters of 
interest and achieves all acceptable performance criteria (Section 12) 
may be used. GC to MS interfaces constructed of all glass or glass-lined 
materials are recommended. Glass can be deactivated by silanizing with 
dichlorodimethylsilane.
    5.6.6  Data system--A computer system must be interfaced to the mass 
spectrometer that allows the contiluous acquisition and storage on 
machine-readable media of all mass spectra obtained throughout the 
duration of the chromatographic program. The computer must have software 
that allows searching any GC/MS data file for specific m/z and plotting 
such m/z abundances versus time or scan number. This type of plot is 
defined as an Extracted Ion Current Profile (EICP). Software must also 
be available that

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allows integrating the abundance in any EICP between specified time or 
scan number limits.

                               6. Reagents

    6.1  Reagent water--Reagent water is defined as a water in which an 
interferent is not observed at the MDL of the parameters of interest.
    6.2  Sodium hydroxide solution (10 N)--Dissolve 40 g of NaOH (ACS) 
in reagent water and dilute to 100 mL.
    6.3  Sodium thiosulfate--(ACS) Granular.
    6.4  Sulfuric acid (1+1)--Slowly, add 50 mL of 
H2SO4 (ACS, sp. gr. 1.84) to 50 mL of reagent 
water.
    6.5  Acetone, methanol, methlylene chloride--Pesticide quality or 
equivalent.
    6.6  Sodium sulfate--(ACS) Granular, anhydrous. Purify by heating at 
400  deg.C for 4 h in a shallow tray.
    6.7  Stock standard solutions (1.00 [mu]g/[mu]L)--standard solutions 
can be prepared from pure standard materials or purchased as certified 
solutions.
    6.7.1  Prepare stock standard solutions by accurately weighing about 
0.0100 g of pure material. Dissolve the material in pesticide quality 
acetone or other suitable solvent and dilute to volume in a 10-mL 
volumetric flask. Larger volumes can be used at the convenience of the 
analyst. When compound purity is assayed to be 96% or greater, the 
weight may be used without correction to calculate the concentration of 
the stock standard. Commercially prepared stock standards may be used at 
any concentration if they are certified by the manufacturer or by an 
independent source.
    6.7.2  Transfer the stock standard solutions into Teflon-sealed 
screw-cap bottles. Store at 4  deg.C and protect from light. Stock 
standard solutions should be checked frequently for signs of degradation 
or evaporation, especially just prior to preparing calibration standards 
from them.
    6.7.3  Stock standard solutions must be replaced after six months, 
or sooner if comparison with quality control check samples indicate a 
problem.
    6.8  Surrogate standard spiking solution--Select a minimum of three 
surrogate compounds from Table 8. Prepare a surrogate standard spiking 
solution containing each selected surrogate compound at a concentration 
of 100 [mu]g/mL in acetone. Addition of 1.00 mL of this solution to 1000 
mL of sample is equivalent to a concentration of 100 [mu]g/L of each 
surrogate standard. Store the spiking solution at 4  deg.C in Teflon-
sealed glass container. The solution should be checked frequently for 
stability. The solution must be replaced after six months, or sooner if 
comparison with quality control check standards indicates a problem.
    6.9  DFTPP standard--Prepare a 25 [mu]g/mL solution of DFTPP in 
acetone.
    6.10  Quality control check sample concentrate--See Section 8.2.1.

                             7. Calibration

    7.1  Establish gas chromatographic operating parameters equivalent 
to those indicated in Table 4 or 5.
    7.2  Internal standard calibration procedure--To use this approach, 
the analyst must select three or more internal standards that are 
similar in analytical behavior to the compounds of interest. The analyst 
must further demonstrate that the measurement of the internal standards 
is not affected by method or matrix interferences. Some recommended 
internal standards are listed in Table 8. Use the base peak m/z as the 
primary m/z for quantification of the standards. If interferences are 
noted, use one of the next two most intense m/z quantities for 
quantification.
    7.2.1  Prepare calibration standards at a minimum of three 
concentration levels for each parameter of interest by adding 
appropriate volumes of one or more stock standards to a volumetric 
flask. To each calibration standard or standard mixture, add a known 
constant amount of one or more internal standards, and and dilute to 
volume with acetone. One of the calibration standards should be at a 
concentration near, but above, the MDL and the other concentrations 
should correspond to the expected range of concentrations found in real 
samples or should define the working range of the GC/MS system.
    7.2.2  Using injections of 2 to 5 [mu]L, analyze each calibration 
standard according to Section 13 and tabulate the area of the primary 
characteristic m/z (Tables 4 and 5) against concentration for each 
compound and internal standard. Calculate response factors (RF) for each 
compound using Equation 1.
[GRAPHIC] [TIFF OMITTED] TC15NO91.126

                                                              Equation 1
where:
As=Area of the characteristic m/z for the parameter to be 
measured.
Ais=Area of the characteristic m/z for the internal standard.
Cis=Concentration of the internal standard ([mu]g/L).
Cs=Concentration of the parameter to be measured ([mu]g/L).

If the RF value over the working range is a constant (<35% RSD), the RF 
can be assumed to be invariant and the average RF can be used for 
calculations. Alternatively, the results can be used to plot a 
calibration curve of response ratios, As/Ais, vs. 
RF.
    7.3  The working calibration curve or RF must be verified on each 
working day by the

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measurement of one or more calibration standards. If the response for 
any parameter varies from the predicted response by more than 
20%, the test must be repeated uning a fresh calibration 
standard. Alternatively, a new calibration curve must be prepared for 
that compound.

                           8. Quality Control

    8.1  Each laboratory that uses this method is required to operate a 
formal quality control program. The minimum requirements of this program 
consist of an initial demonstration of laboratory capability and an 
ongoing analysis of spiked samples to evaluate and document data 
quality. The laboratory must maintain records to document the quality of 
data that is generated. Ongoing data quality checks are compared with 
established performance criteria to determine if the results of analyses 
meet the performance characteristics of the method. When results of 
sample spikes indicate atypical method performance, a quality control 
check standard must be analyzed to confirm that the measurements were 
performed in an in-control mode of operation.
    8.1.1  The analyst must make an initial, one-time, demonstration of 
the ability to generate acceptable accuracy and precision with this 
method. This ability is established as described in Section 8.2.
    8.1.2  In recognition of advances that are occuring in 
chromatography, the analyst is permitted certain options (detailed in 
Sections 10.6 and 13.1) to improve the separations or lower the cost of 
measurements. Each time such a modification is made to the method, the 
analyst is required to repeat the procedure in Section 8.2.
    8.1.3  Before processing any samples, the analyst must analyze a 
reagent water blank to demonstrate that interferences from the 
analytical system and glassware are under control. Each time a set of 
samples is extracted or reagents are changed, a reagent water blank must 
be processed as a safeguard against laboratory contamination.
    8.1.4  The laboratory must, on an ongoing basis, spike and analyze a 
minimum of 5% of all samples to monitor and evaluate laboratory data 
quality. This procedure is described in Section 8.3.
    8.1.5  The laboratory must, on an ongoing basis, demonstrate through 
the analyses of quality control check standards that the operation of 
the measurement system is in control. This procedure is described in 
Section 8.4. The frequency of the check standard analyses is equivalent 
to 5% of all samples analyzed but may be reduced if spike recoveries 
from samples (Section 8.3) meet all specified quality control criteria.
    8.1.6  The laboratory must maintain performance records to document 
the quality of data that is generated. This procedure is described in 
Section 8.5.
    8.2  To establish the ability to generate acceptable accuracy and 
precision, the analyst must perform the following operations.
    8.2.1  A quality control (QC) check sample concentrate is required 
containing each parameter of interest at a concentration of 100 [mu]g/mL 
in acetone. Multiple solutions may be required. PCBs and multicomponent 
pesticides may be omitted from this test. The QC check sample 
concentrate must be obtained from the U.S. Environmental Protection 
Agency, Environmental Monitoring and Support Laboratory in Cincinnati, 
Ohio, if available. If not available from that source, the QC check 
sample concentrate must be obtained from another external source. If not 
available from either source above, the QC check sample concentrate must 
be prepared by the laboratory using stock standards prepared 
independently from those used for calibration.
    8.2.2  Using a pipet, prepare QC check samples at a concentration of 
100 [mu]g/L by adding 1.00 mL of QC check sample concentrate to each of 
four 1-L aliquots of reagent water.
    8.2.3  Analyze the well-mixed QC check samples according to the 
method beginning in Section 10 or 11.
    8.2.4  Calculate the average recovery (X) in [mu]g/L, and the 
standard deviation of the recovery (s) in [mu]g/L, for each parameter 
using the four results.
    8.2.5  For each parameter compare s and X with the corresponding 
acceptance criteria for precision and accuracy, respectively, found in 
Table 6. If s and X for all parameters of interest meet the acceptance 
criteria, the system performance is acceptable and analysis of actual 
samples can begin. If any individual s exceeds the precision limit or 
any individual X falls outside the range for accuracy, the system 
performance is unacceptable for that parameter.
    Note: The large number of parameters in Table 6 present a 
substantial probability that one or more will fail at least one of the 
acceptance criteria when all parameters are analyzed.
    8.2.6  When one or more of the parameters tested fail at least one 
of the acceptance criteria, the analyst must proceed according to 
Section 8.2.6.1 or 8.2.6.2.
    8.2.6.1  Locate and correct the source of the problem and repeat the 
test for all parameters of interest beginning with Section 8.2.2.
    8.2.6.2  Beginning with Section 8.2.2, repeat the test only for 
those parameters that failed to meet criteria. Repeated failure, 
however, will confirm a general problem with the measurement system. If 
this occurs, locate and correct the source of the problem and repeat the 
test for all compounds of interest beginning with Section 8.2.2.
    8.3  The laboratory must, on an ongoing basis, spike at least 5% of 
the samples from each sample site being monitored to assess

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accuracy. For laboratories analyzing 1 to 20 samples per month, at least 
one spiked sample per month is required.
    8.3.1.  The concentration of the spike in the sample should be 
determined as follows:
    8.3.1  If, as in compliance monitoring, the concentration of a 
specific parameter in the sample is being checked against a regulatory 
concentration limit, the spike should be at that limit or 1 to 5 times 
higher than the background concentration determined in Section 8.3.2, 
whichever concentration would be larger.
    8.3.1.2  If the concentration of a specific parameter in the sample 
is not being checked against a limit specific to that parameter, the 
spike should be at 100 [mu]g/L or 1 to 5 times higher than the 
background concentration determined in Section 8.3.2, whichever 
concentration would be larger.
    8.3.1.3  If it is impractical to determine background levels before 
spiking (e.g., maximum holding times will be exceeded), the spike 
concentration should be (1) the regulatory concentration limit, if any; 
or, if none (2) the larger of either 5 times higher than the expected 
background concentration or 100 [mu]g/L.
    8.3.2  Analyze one sample aliquot to determine the background 
concentration (B) of each parameter. If necessary, prepare a new QC 
check sample concentrate (Section 8.2.1) appropriate for the background 
concentrations in the sample. Spike a second sample aliquot with 1.0 mL 
of the QC check sample concentrate and analyze it to determine the 
concentration after spiking (A) of each parameter. Calculate each 
percent recovery (P) as 100(A-B)%/T, where T is the known true value of 
the spike.
    8.3.3  Compare the percent recovery (P) for each parameter with the 
corresponding QC acceptance criteria found in Table 6. These acceptance 
criteria were calculated to include an allowance for error in 
measurement of both the background and spike concentrations, assuming a 
spike to background ratio of 5:1. This error will be accounted for to 
the extent that the analyst's spike to background ratio approaches 
5:1.7 If spiking was performed at a concentration lower than 
100 [mu]g/L, the analyst must use either the QC acceptance criteria in 
Table 6, or optional QC acceptance criteria calculated for the specific 
spike concentration. To calculate optional acceptance criteria for the 
recovery of a parameter: (1) Calculate accuracy (X') using the equation 
in Table 7, substituting the spike concentration (T) for C; (2) 
calculate overall precision (S') using the equation in Table 7, 
substituting X' for X; (3) calculate the range for recovery at the spike 
concentration as (100 X'/T)2.44(100 S'/T)%7
    8.3.4  If any individual P falls outside the designated range for 
recovery, that parameter has failed the acceptance criteria. A check 
standard containing each parameter that failed the criteria must be 
analyzed as described in Section 8.4.
    8.4  If any parameter fails the acceptance criteria for recovery in 
Section 8.3, a QC check standard containing each parameter that failed 
must be prepared and analyzed.
    Note: The frequency for the required analysis of a QC check standard 
will depend upon the number of parameters being simultaneously tested, 
the complexity of the sample matrix, and the performance of the 
laboratory. If the entire list of single-component parameters in Table 6 
must be measured in the sample in Section 8.3, the probability that the 
analysis of a QC check standard will be required is high. In this case 
the QC check standard should be routinely analyzed with the spike 
sample.
    8.4.1  Prepare the QC check standard by adding 1.0 mL of QC check 
sample concentrate (Section 8.2.1 or 8.3.2) to 1 L of reagent water. The 
QC check standard needs only to contain the parameters that failed 
criteria in the test in Section 8.3.
    8.4.2  Analyze the QC check standard to determine the concentration 
measured (A) of each parameter. Calculate each percent recovery 
(PS) as 100 (A/T)%, where T is the true value of the standard 
concentration.
    8.4.3  Compare the percent recovery (Ps) for each 
parameter with the corresponding QC acceptance criteria found in Table 
6. Only parameters that failed the test in Section 8.3 need to be 
compared with these criteria. If the recovery of any such parameter 
falls outside the designated range, the laboratory performance for that 
parameter is judged to be out of control, and the problem must be 
immediately identified and corrected. The analytical result for that 
parameter in the unspiked sample is suspect and may not be reported for 
regulatory compliance purposes.
    8.5  As part of the QC program for the laboratory, method accuracy 
for wastewater samples must be assessed and records must be maintained. 
After the analysis of five spiked wastewater samples as in Section 8.3, 
calculate the average percent recovery (P) and the standard deviation of 
the percent recovery (sp). Express the accuracy assessment as 
a percent interval from P-2sp to P+2sp. If P=90% 
and sp=10%, for example, the accuracy interval is expressed 
as 70-110%. Update the accuracy assessment for each parameter on a 
regular basis (e.g. after each five to ten new accuracy measurements).
    8.6  As a quality control check, the laboratory must spike all 
samples with the surrogate standard spiking solution as described in 
Section 10.2, and calculate the percent recovery of each surrogate 
compound.
    8.7  It is recommended that the laboratory adopt additional quality 
assurance practices for use with this method. The specific practices 
that are most productive depend upon the needs of the laboratory and the 
nature of

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the samples. Field duplicates may be analyzed to assess the precision of 
the environmental measurements. Whenever possible, the laboratory should 
analyze standard reference materials and participate in relevant 
performance evaluation studies.

            9. Sample Collection, Preservation, and Handling

    9.1  Grab samples must be collected in glass containers. 
Conventional sampling practices 8 should be followed, except 
that the bottle must not be prerinsed with sample before collection. 
Composite samples should be collected in refrigerated glass containers 
in accordance with the requirements of the program. Automatic sampling 
equipment must be as free as possible of Tygon tubing and other 
potential sources of contamination.
    9.2  All sampling must be iced or refrigerated at 4  deg.C from the 
time of collection until extraction. Fill the sample bottles and, if 
residual chlorine is present, add 80 mg of sodium thiosulfate per liter 
of sample and mix well. EPA Methods 330.4 and 330.5 may be used for 
measurement of residual chlorine.9 Field test kits are 
available for this purpose.
    9.3  All samples must be extracted within 7 days of collection and 
completely analyzed within 40 days of extraction.

                    10. Separatory Funnel Extraction

    10.1  Samples are usually extracted using separatory funnel 
techniques. If emulsions will prevent achieving acceptable solvent 
recovery with separatory funnel extractions, continuous extraction 
(Section 11) may be used. The separatory funnel extraction scheme 
described below assumes a sample volume of 1 L. When sample volumes of 2 
L are to be extracted, use 250, 100, and 100-mL volumes of methylene 
chloride for the serial extraction of the base/neutrals and 200, 100, 
and 100-mL volumes of methylene chloride for the acids.
    10.2  Mark the water meniscus on the side of the sample bottle for 
later determination of sample volume. Pour the entire sample into a 2-L 
separatory funnel. Pipet 1.00 mL of the surrogate standard spiking 
solution into the separatory funnel and mix well. Check the pH of the 
sample with wide-range pH paper and adjust to pH11 with 
sodium hydroxide solution.
    10.3  Add 60 mL of methylene chloride to the sample bottle, seal, 
and shake for 30 s to rinse the inner surface. Transfer the solvent to 
the separatory funnel and extract the sample by shaking the funnel for 2 
min. with periodic venting to release excess pressure. Allow the organic 
layer to separate from the water phase for a minimum of 10 min. If the 
emulsion interface between layers is more than one-third the volume of 
the solvent layer, the analyst must employ mechanical techniques to 
complete the phase separation. The optimum technique depends upon the 
sample, but may include stirring, filtration of the emulsion through 
glass wool, centrifugation, or other physical methods. Collect the 
methylene chloride extract in a 250-mL Erlenmeyer flask. If the emulsion 
cannot be broken (recovery of less than 80% of the methylene chloride, 
corrected for the water solubility of methylene chloride), transfer the 
sample, solvent, and emulsion into the extraction chamber of a 
continuous extractor and proceed as described in Section 11.3.
    10.4  Add a second 60-mL volume of methylene chloride to the sample 
bottle and repeat the extraction procedure a second time, combining the 
extracts in the Erlenmeyer flask. Perform a third extraction in the same 
manner. Label the combined extract as the base/neutral fraction.
    10.5  Adjust the pH of the aqueous phase to less than 2 using 
sulfuric acid. Serially extract the acidified aqueous phase three times 
with 60-mL aliquots of methylene chloride. Collect and combine the 
extracts in a 250-mL Erlenmeyer flask and label the combined extracts as 
the acid fraction.
    10.6  For each fraction, assemble a Kuderna-Danish (K-D) 
concentrator by attaching a 10-mL concentrator tube to a 500-mL 
evaporative flask. Other concentration devices or techniques may be used 
in place of the K-D concentrator if the requirements of Section 8.2 are 
met.
    10.7  For each fraction, pour the combined extract through a 
solvent-rinsed drying column containing about 10 cm of anhydrous sodium 
sulfate, and collect the extract in the K-D concentrator. Rinse the 
Erlenmeyer flask and column with 20 to 30 mL of methylene chloride to 
complete the quantitative transfer.
    10.8  Add one or two clean boiling chips and attach a three-ball 
Snyder column to the evaporative flask for each fraction. Prewet each 
Snyder column by adding about 1 mL of methylene chloride to the top. 
Place the K-D apparatus on a hot water bath (60 to 65  deg.C) so that 
the concentrator tube is partially immersed in the hot water, and the 
entire lower rounded surface of the flask is bathed with hot vapor. 
Adjust the vertical position of the apparatus and the water temperature 
as required to complete the concentration in 15 to 20 min. At the proper 
rate of distillation the balls of the column will actively chatter but 
the chambers will not flood with condensed solvent. When the apparent 
volume of liquid reaches 1 mL, remove the K-D apparatus from the water 
bath and allow it to drain and cool for at least 10 min. Remove the 
Snyder column and rinse the flask and its lower joint into the 
concentrator tube with 1 to 2 mL of methylene chloride. A 5-mL syringe 
is recommended for this operation.

[[Page 207]]

    10.9  Add another one or two clean boiling chips to the concentrator 
tube for each fraction and attach a two-ball micro-Snyder column. Prewet 
the Snyder column by adding about 0.5 mL of methylene chloride to the 
top. Place the K-D apparatus on a hot water bath (60 to 65  deg.C) so 
that the concentrator tube is partially immersed in hot water. Adjust 
the vertical position of the apparatus and the water temperature as 
required to complete the concentration in 5 to 10 min. At the proper 
rate of distillation the balls of the column will actively chatter but 
the chambers will not flood with condensed solvent. When the apparent 
volume of liquid reaches about 0.5 mL, remove the K-D apparatus from the 
water bath and allow it to drain and cool for at least 10 min. Remove 
the Snyder column and rinse the flask and its lower joint into the 
concentrator tube with approximately 0.2 mL of acetone or methylene 
chloride. Adjust the final volume to 1.0 mL with the solvent. Stopper 
the concentrator tube and store refrigerated if further processing will 
not be performed immediately. If the extracts will be stored longer than 
two days, they should be transferred to Teflon-sealed screw-cap vials 
and labeled base/neutral or acid fraction as appropriate.
    10.10  Determine the original sample volume by refilling the sample 
bottle to the mark and transferring the liquid to a 1000-mL graduated 
cylinder. Record the sample volume to the nearest 5 mL.

                        11. Continuous Extraction

    11.1  When experience with a sample from a given source indicates 
that a serious emulsion problem will result or an emulsion is 
encountered using a separatory funnel in Section 10.3, a continuous 
extractor should be used.
    11.2  Mark the water meniscus on the side of the sample bottle for 
later determination of sample volume. Check the pH of the sample with 
wide-range pH paper and adjust to pH 11 with sodium hydroxide 
solution. Transfer the sample to the continuous extractor and using a 
pipet, add 1.00 mL of surrogate standard spiking solution and mix well. 
Add 60 mL of methylene chloride to the sample bottle, seal, and shake 
for 30 s to rinse the inner surface. Transfer the solvent to the 
extractor.
    11.3  Repeat the sample bottle rinse with an additional 50 to 100-mL 
portion of methylene chloride and add the rinse to the extractor.
    11.4  Add 200 to 500 mL of methylene chloride to the distilling 
flask, add sufficient reagent water to ensure proper operation, and 
extract for 24 h. Allow to cool, then detach the distilling flask. Dry, 
concentrate, and seal the extract as in Sections 10.6 through 10.9.
    11.5  Charge a clean distilling flask with 500 mL of methylene 
chloride and attach it to the continuous extractor. Carefully, while 
stirring, adjust the pH of the aqueous phase to less than 2 using 
sulfuric acid. Extract for 24 h. Dry, concentrate, and seal the extract 
as in Sections 10.6 through 10.9.

                    12. Daily GC/MS Performance Tests

    12.1  At the beginning of each day that analyses are to be 
performed, the GC/MS system must be checked to see if acceptable 
performance criteria are achieved for DFTPP.10 Each day that 
benzidine is to be determined, the tailing factor criterion described in 
Section 12.4 must be achieved. Each day that the acids are to be 
determined, the tailing factor criterion in Section 12.5 must be 
achieved.
    12.2  These performance tests require the following instrumental 
parameters:

Electron Energy: 70 V (nominal)
Mass Range: 35 to 450 amu
Scan Time: To give at least 5 scans per peak but not to exceed 7 s per 
scan.

    12.3  DFTPP performance test--At the beginning of each day, inject 2 
[mu]L (50 ng) of DFTPP standard solution. Obtain a background-corrected 
mass spectra of DFTPP and confirm that all the key m/z criteria in Table 
9 are achieved. If all the criteria are not achieved, the analyst must 
retune the mass spectrometer and repeat the test until all criteria are 
achieved. The performance criteria must be achieved before any samples, 
blanks, or standards are analyzed. The taililg factor tests in Sections 
12.4 and 12.5 may be performed simultaneously with the DFTPP test.
    12.4  Column performance test for base/neutrals--At the beginning of 
each day that the base/neutral fraction is to be analyzed for benzidine, 
the benzidine tailing factor must be calculated. Inject 100 ng of 
benzidine either separately or as a part of a standard mixture that may 
contain DFTPP and calculate the tailing factor. The benzidine tailing 
factor must be less than 3.0. Calculation of the tailing factor is 
illustrated in Figure 13.\11\ Replace the column packing if the tailing 
factor criterion cannot be achieved.
    12.5  Column performance test for acids--At the beginning of each 
day that the acids are to be determined, inject 50 ng of 
pentachlorophenol either separately or as a part of a standard mix that 
may contain DFTPP. The tailing factor for pentachlorophenol must be less 
than 5. Calculation of the tailing factor is illustrated in Figure 
13.\11\ Replace the column packing if the tailing factor criterion 
cannot be achieved.

                13. Gas Chromatography/Mass Spectrometry

    13.1  Table 4 summarizes the recommended gas chromatographic 
operating conditions for the base/neutral fraction. Table 5 summarizes 
the recommended gas chromatographic

[[Page 208]]

operating conditions for the acid fraction. Included in these tables are 
retention times and MDL that can be achieved under these conditions. 
Examples of the separations achieved by these columns are shown in 
Figures 1 through 12. Other packed or capillary (open-tubular) columns 
or chromatographic conditions may be used if the requirements of Section 
8.2 are met.
    13.2  After conducting the GC/MS performance tests in Section 12, 
calibrate the system daily as described in Section 7.
    13.3  The internal standard must be added to sample extract and 
mixed thoroughly immediately before it is injected into the instrument. 
This procedure minimizes losses due to adsorption, chemical reaction or 
evaporation.
    13.4  Inject 2 to 5 [mu]L of the sample extract or standard into the 
GC/MS system using the solvent-flush technique.\12\ Smaller (1.0 [mu]L) 
volumes may be injected if automatic devices are employed. Record the 
volume injected to the nearest 0.05 [mu]L.
    13.5  If the response for any m/z exceeds the working range of the 
GC/MS system, dilute the extract and reanalyze.
    13.6  Perform all qualitative and quantitative measurements as 
described in Sections 14 and 15. When the extracts are not being used 
for analyses, store them refrigerated at 4 deg.C, protected from light 
in screw-cap vials equipped with unpierced Teflon-lined septa.

                     14. Qualitative Identification

    14.1  Obtain EICPs for the primary m/z and the two other masses 
listed in Tables 4 and 5. See Section 7.3 for masses to be used with 
internal and surrogate standards. The following criteria must be met to 
make a qualitative identification:
    14.1.1  The characteristic masses of each parameter of interest must 
maximize in the same or within one scan of each other.
    14.1.2  The retention time must fall within 30 s of the 
retention time of the authentic compound.
    14.1.3  The relative peak heights of the three characteristic masses 
in the EICPs must fall within 20% of the relative 
intensities of these masses in a reference mass spectrum. The reference 
mass spectrum can be obtained from a standard analyzed in the GC/MS 
system or from a reference library.
    14.2  Structural isomers that have very similar mass spectra and 
less than 30 s difference in retention time, can be explicitly 
identified only if the resolution between authentic isomers in a 
standard mix is acceptable. Acceptable resolution is achieved if the 
baseline to valley height between the isomers is less than 25% of the 
sum of the two peak heights. Otherwise, structural isomers are 
identified as isomeric pairs.

                            15. Calculations

    15.1  When a parameter has been identified, the quantitation of that 
parameter will be based on the integrated abundance from the EICP of the 
primary characteristic m/z in Tables 4 and 5. Use the base peak m/z for 
internal and surrogate standards. If the sample produces an interference 
for the primary m/z, use a secondary characteristic m/z to quantitate.
    Calculate the concentration in the sample using the response factor 
(RF) determined in Section 7.2.2 and Equation 3.
[GRAPHIC] [TIFF OMITTED] TC15NO91.127

                                                              Equation 3

where:
As=Area of the characteristic m/z for the parameter or 
surrogate standard to be measured.
Ais=Area of the characteristic m/z for the internal standard.
Is=Amount of internal standard added to each extract ([mu]g).
Vo=Volume of water extracted (L).

    15.2  Report results in [mu]g/L without correction for recovery 
data. All QC data obtained should be reported with the sample results.

                         16. Method Performance

    16.1  The method detection limit (MDL) is defined as the minimum 
concentration of a substance that can be measured and reported with 99% 
confidence that the value is above zero.1 The MDL 
concentrations listed in Tables 4 and 5 were obtained using reagent 
water.13 The MDL actually achieved in a given analysis will 
vary depending on instrument sensitivity and matrix effects.
    16.2  This method was tested by 15 laboratories using reagent water, 
drinking water, surface water, and industrial wastewaters spiked at six 
concentrations over the range 5 to 1300 [mu]g/L.14 Single 
operator precision, overall precision, and method accuracy were found to 
be directly related to the concentration of the parameter and 
essentially independent of the sample matrix. Linear equations to 
describe these relationships are presented in Table 7.

    17. Screening Procedure for 2,3,7,8-Tetrachlorodibenzo-p-dioxin 
                             (2,3,7,8-TCDD)

    17.1  If the sample must be screened for the presence of 2,3,7,8-
TCDD, it is recommended that the reference material not be handled in 
the laboratory unless extensive safety precautions are employed. It is 
sufficient to analyze the base/neutral extract by selected ion 
monitoring (SIM) GC/MS techniques, as follows:
    17.1.1  Concentrate the base/neutral extract to a final volume of 
0.2 ml.

[[Page 209]]

    17.1.2  Adjust the temperature of the base/neutral column (Section 
5.6.2) to 220  deg.C.
    17.1.3  Operate the mass spectrometer to acquire data in the SIM 
mode using the ions at m/z 257, 320 and 322 and a dwell time no greater 
than 333 milliseconds per mass.
    17.1.4  Inject 5 to 7 [mu]L of the base/neutral extract. Collect SIM 
data for a total of 10 min.
    17.1.5  The possible presence of 2,3,7,8-TCDD is indicated if all 
three masses exhibit simultaneous peaks at any point in the selected ion 
current profiles.
    17.1.6  For each occurrence where the possible presence of 2,3,7,8-
TCDD is indicated, calculate and retain the relative abundances of each 
of the three masses.
    17.2  False positives to this test may be caused by the presence of 
single or coeluting combinations of compounds whose mass spectra contain 
all of these masses.
    17.3  Conclusive results of the presence and concentration level of 
2,3,7,8-TCDD can be obtained only from a properly equipped laboratory 
through the use of EPA Method 613 or other approved alternate test 
procedures.

                               References

    1. 40 CFR part 136, appendix B.
    2. ``Sampling and Analysis Procedures for Screening of Industrial 
Effluents for Priority Pollutants,'' U.S. Environmental Protection 
Agency, Environmental Monitoring and Support Laboratory, Cincinnati, 
Ohio 45268, March 1977, Revised April 1977. Available from Effluent 
Guidelines Division, Washington, DC 20460.
    3. ASTM Annual Book of Standards, Part 31, D3694-78. ``Standard 
Practices for Preparation of Sample Containers and for Preservation of 
Organic Constituents,'' American Society for Testing and Materials, 
Philadelphia.
    4. ``Carcinogens--Working With Carcinogens,'' Department of Health, 
Education, and Welfare, Public Health Service, Center for Disease 
Control, National Institute for Occupational Safety and Health, 
Publication No. 77-206, August 1977.
    5. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR 
part 1910), Occupational Safety and Health Administration, OSHA 2206 
(Revised, January 1976).
    6. ``Safety in Academic Chemistry Laboratories,''American Chemical 
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
    7. Provost, L.P., and Elder, R.S. ``Interpretation of Percent 
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44 
used in the equation in Section 8.3.3 is two times the value 1.22 
derived in this report.)
    8. ASTM Annual Book of Standards, Part 31, D3370-76. ``Standard 
Practices for Sampling Water,'' American Society for Testing and 
Materials, Philadelphia.
    9. ``Methods 330.4 (Titrimetric, DPD-FAS) and 330.5 
(Spectrophotometric, DPD) for Chlorine, Total Residual,'' Methods for 
Chemical Analysis of Water and Wastes, EPA-600/4-79-020, U.S. 
Environmental Protection Agency, Environmental Monitoring and Support 
Laboratory, Cincinnati, Ohio 45268, March 1979.
    10. Eichelberger, J.W., Harris, L.E., and Budde, W.L. ``Reference 
Compound to Calibrate Ion Abundance Measurement in Gas Chromatography-
Mass Spectometry,'' Analytical Chemistry, 47, 995 (1975).
    11. McNair, N.M. and Bonelli, E.J. ``Basic Chromatography,'' 
Consolidated Printing, Berkeley, California, p. 52, 1969.
    12. Burke, J.A. ``Gas Chromatography for Pesticide Residue Analysis; 
Some Practical Aspects,'' Journal of the Association of Official 
Analytical Chemists, 48, 1037 (1965).
    13. Olynyk, P., Budde, W.L., and Eichelberger, J.W. ``Method 
Detection Limit for Methods 624 and 625,'' Unpublished report, May 14, 
1980.
    14. ``EPA Method Study 30, Method 625, Base/Neutrals, Acids, and 
Pesticides,'' EPA 600/4-84-053, National Technical Information Service, 
PB84-206572, Springfield, Virginia 22161, June 1984.

                   Table 1--Base/Neutral Extractables
------------------------------------------------------------------------
                                                    STORET
                    Parameter                         No.      CAS No.
------------------------------------------------------------------------
Acenaphthene.....................................     34205      83-32-9
Acenaphthylene...................................     34200     208-96-8
Anthracene.......................................     34220     120-12-7
Aldrin...........................................     39330     309-00-2
Benzo(a)anthracene...............................     34526      56-55-3
Benzo(b)fluoranthene.............................     34230     205-99-2
Benzo(k)fluoranthene.............................     34242     207-08-9
Benzo(a)pyrene...................................     34247      50-32-8
Benzo(ghi)perylene...............................     34521     191-24-2
Benzyl butyl phthalate...........................     34292      85-68-7
[beta]-BHC.......................................     39338     319-85-7
[delta]-BHC......................................     34259     319-86-8
Bis(2-chloroethyl) ether.........................     34273     111-44-4
Bis(2-chloroethoxy)methane.......................     34278     111-91-1
Bis(2-ethylhexyl) phthalate......................     39100     117-81-7
Bis(2-chloroisopropyl) ether a...................     34283     108-60-1
4-Bromophenyl phenyl ether a.....................     34636     101-55-3
Chlordane........................................     39350      57-74-9
2-Chloronaphthalele..............................     34581      91-58-7
4-Chlorophenyl phenyl ether......................     34641    7005-72-3
Chrysene.........................................     34320     218-01-9
4,4'-DDD.........................................     39310      72-54-8
4,4'-DDE.........................................     39320      72-55-9
4,4'-DDT.........................................     39300      50-29-3
Dibenzo(a,h)anthracene...........................     34556      53-70-3
Di-n-butylphthalate..............................     39110      84-74-2
1,3-Dichlorobenzene..............................     34566     541-73-1
1,2-Dichlorobenzene..............................     34536      95-50-1
1,4-Dichlorobenzene..............................     34571     106-46-7
3,3'-Dichlorobenzidine...........................     34631      91-94-1
Dieldrin.........................................     39380      60-57-1
Diethyl phthalate................................     34336      84-66-2
Dimethyl phthalate...............................     34341     131-11-3
2,4-Dinitrotoluene...............................     34611     121-14-2
2,6-Dinitrotoluene...............................     34626     606-20-2
Di-n-octylphthalate..............................     34596     117-84-0
Endosulfan sulfate...............................     34351    1031-07-8

[[Page 210]]

 
Endrin aldehyde..................................     34366    7421-93-4
Fluoranthene.....................................     34376     206-44-0
Fluorene.........................................     34381      86-73-7
Heptachlor.......................................     39410      76-44-8
Heptchlor epoxide................................     39420    1024-57-3
Hexachlorobenzene................................     39700     118-74-1
Hexachlorobutadiene..............................     34391      87-68-3
Hexachloroethane.................................     34396      67-72-1
Indeno(1,2,3-cd)pyrene...........................     34403     193-39-5
Isophorone.......................................     34408      78-59-1
Naphthalene......................................     34696      91-20-3
Nitrobenzene.....................................     34447      98-95-3
N-Nitrosodi-n-propylamine........................     34428     621-64-7
PCB-1016.........................................     34671   12674-11-2
PCB-1221.........................................     39488   11104-28-2
PCB-1232.........................................     39492   11141-16-5
PCB-1242.........................................     39496   53469-21-9
PCB-1248.........................................     39500   12672-29-6
PCB-1254.........................................     39504   11097-69-1
PCB-1260.........................................     39508   11096-82-5
Phenanthrene.....................................     34461      85-01-8
Pyrene...........................................     34469     129-00-0
Toxaphene........................................     39400    8001-35-2
1,2,4-Trichlorobenzene...........................     34551     120-82-1
------------------------------------------------------------------------
a The proper chemical name is 2,2'-oxybis(1-chloropropane).


                       Table 2--Acid Extractables
------------------------------------------------------------------------
                                                    STORET
                    Parameter                         No.      CAS No.
------------------------------------------------------------------------
4-Chloro-3-methylphenol..........................     34452      59-50-7
2-Chlorophenol...................................     34586      95-57-8
2,4-Dichlorophenol...............................     34601     120-83-2
2,4-Dimethylphenol...............................     34606     105-67-9
2,4-Dinitrophenol................................     34616      51-28-5
2-Methyl-4,6-dinitrophenol.......................     34657     534-52-1
2-Nitrophenol....................................     34591      88-75-5
4-Nitrophenol....................................     34646     100-02-7
Pentachlorophenol................................     39032      87-86-5
Phenol...........................................     34694     108-95-2
2,4,6-Trichlorophenol............................     34621      88-06-2
------------------------------------------------------------------------


              Table 3--Additional Extractable Parameters a
------------------------------------------------------------------------
                                            STORET
                Parameter                     No.      CAS No.    Method
------------------------------------------------------------------------
Benzidine................................     39120      92-87-5     605
[beta]-BHC...............................     39337     319-84-6     608
[delta]-BHC..............................     39340      58-89-8     608
Endosulfan I.............................     34361     959-98-8     608
Endosulfan II............................     34356   33213-65-9     608
Endrin...................................     39390      72-20-8     608
Hexachlorocylopentadiene.................     34386      77-47-4     612
N-Nitrosodimethylamine...................     34438      62-75-9     607
N-Nitrosodiphenylamine...................     34433      86-30-6     607
------------------------------------------------------------------------
a See Section 1.2.


    Table 4--Chromatographic Conditions, Method Detection Limits, and Characteristic Masses for Base/Neutral
                                                  Extractables
----------------------------------------------------------------------------------------------------------------
                                                                        Characteristic masses
                              Retention    Method  -------------------------------------------------------------
          Parameter              time    detection          Electron impact              Chemical ionization
                                (min)      limit   -------------------------------------------------------------
                                         ([mu]g/L)   Primary  Secondary  Secondary   Methane   Methane   Methane
----------------------------------------------------------------------------------------------------------------
1,3-Dichlorobenzene.........        7.4        1.9       146        148        113       146       148       150
1,4-Dichlorobenzene.........        7.8        4.4       146        148        113       146       148       150
Hexachloroethane............        8.4        1.6       117        201        199       199       201       203
Bis(2-chloroethyl) ether a..        8.4        5.7        93         63         95        63       107       109
1,2-Dichlorobenzene.........        8.4        1.9       146        148        113       146       148       150
Bis(2-chloroisopropyl) ether        9.3        5.7        45         77         79        77       135       137
 a..........................
N-Nitrosodi-n-propylamine...  .........  .........       130         42        101  ........  ........  ........
Nitrobenzene................       11.1        1.9        77        123         65       124       152       164
Hexachlorobutadiene.........       11.4        0.9       225        223        227       223       225       227
1,2,4-Trichlorobenzene......       11.6        1.9       180        182        145       181       183       209
Isophorone..................       11.9        2.2        82         95        138       139       167       178
Naphthalene.................       12.1        1.6       128        129        127       129       157       169
Bis(2-chloroethoxy) methane.       12.2        5.3        93         95        123        65       107       137
Hexachlorocyclopentadiene a.       13.9  .........       237        235        272       235       237       239
2-Chloronaphthalene.........       15.9        1.9       162        164        127       163       191       203
Acenaphthylene..............       17.4        3.5       152        151        153       152       153       181
Acenaphthene................       17.8        1.9       154        153        152       154       155       183
Dimethyl phthalate..........       18.3        1.6       163        194        164       151       163       164
2,6-Dinitrotoluene..........       18.7        1.9       165         89        121       183       211       223
Fluorene....................       19.5        1.9       166        165        167       166       167       195
4-Chlorophenyl phenyl ether.       19.5        4.2       204        206        141  ........  ........  ........
2,4-Dinitrotoluene..........       19.8        5.7       165         63        182       183       211       223
Diethyl phthalate...........       20.1        1.9       149        177        150       177       223       251
N-Nitrosodiphenylamine b....       20.5        1.9       169        168        167       169       170       198
Hexachlorobenzene...........       21.0        1.9       284        142        249       284       286       288
[beta]-BHC b................       21.1  .........       183        181        109  ........  ........  ........
4-Bromophenyl phenyl ether..       21.2        1.9       248        250        141       249       251       277
[delta]-BHC b...............       22.4  .........       183        181        109  ........  ........  ........
Phenanthrene................       22.8        5.4       178        179        176       178       179       207
Anthracene..................       22.8        1.9       178        179        176       178       179       207
[beta]-BHC..................       23.4        4.2       181        183        109  ........  ........  ........

[[Page 211]]

 
Heptachlor..................       23.4        1.9       100        272        274  ........  ........  ........
[delta]-BHC.................       23.7        3.1       183        109        181  ........  ........  ........
Aldrin......................       24.0        1.9        66        263        220  ........  ........  ........
Dibutyl phthalate...........       24.7        2.5       149        150        104       149       205       279
Heptachlor epoxide..........       25.6        2.2       353        355        351  ........  ........  ........
Endosulfan I b..............       26.4  .........       237        339        341  ........  ........  ........
Fluoranthene................       26.5        2.2       202        101        100       203       231       243
Dieldrin....................       27.2        2.5        79        263        279  ........  ........  ........
4,4'-DDE....................       27.2        5.6       246        248        176  ........  ........  ........
Pyrene......................       27.3        1.9       202        101        100       203       231       243
Endrin b....................       27.9  .........        81        263         82  ........  ........  ........
Endosulfan II b.............       28.6  .........       237        339        341  ........  ........  ........
4,4'-DDD....................       28.6        2.8       235        237        165  ........  ........  ........
Benzidine b.................       28.8         44       184         92        185       185       213       225
4,4'-DDT....................       29.3        4.7       235        237        165  ........  ........  ........
Endosulfan sulfate..........       29.8        5.6       272        387        422  ........  ........  ........
Endrin aldehyde.............  .........  .........        67        345        250  ........  ........  ........
Butyl benzyl phthalate......       29.9        2.5       149         91        206       149       299       327
Bis(2-ethylhexyl) phthalate.       30.6        2.5       149        167        279       149  ........  ........
Chrysene....................       31.5        2.5       228        226        229       228       229       257
Benzo(a)anthracene..........       31.5        7.8       228        229        226       228       229       257
3,3'-Dichlorobenzidine......       32.2       16.5       252        254        126  ........  ........  ........
Di-n-octyl phthalate........       32.5        2.5       149  .........  .........  ........  ........  ........
Benzo(b)fluoranthene........       34.9        4.8       252        253        125       252       253       281
Benzo(k)fluoranthene........       34.9        2.5       252        253        125       252       253       281
Benzo(a)pyrene..............       36.4        2.5       252        253        125       252       253       281
Indeno(1,2,3-cd) pyrene.....       42.7        3.7       276        138        277       276       277       305
Dibenzo(a,h)anthracene......       43.2        2.5       278        139        279       278       279       307
Benzo(ghi)perylene..........       45.1        4.1       276        138        277       276       277       305
N-Nitrosodimethylamine b....  .........  .........        42         74         44  ........  ........  ........
Chlordane c.................      19-30  .........       373        375        377  ........  ........  ........
Toxaphene c.................      25-34  .........       159        231        233  ........  ........  ........
PCB 1016 c..................      18-30  .........       224        260        294  ........  ........  ........
PCB 1221 c..................      15-30         30       190        224        260  ........  ........  ........
PCB 1232 c..................      15-32  .........       190        224        260  ........  ........  ........
PCB 1242 c..................      15-32  .........       224        260        294  ........  ........  ........
PCB 1248 c..................      12-34  .........       294        330        262  ........  ........  ........
PCB 1254 c..................      22-34         36       294        330        362  ........  ........  ........
PCB 1260 c..................      23-32  .........       330        362        394  ........  ........  ........
----------------------------------------------------------------------------------------------------------------
a The proper chemical name is 2,2'-bisoxy(1-chloropropane).
b See Section 1.2.
c These compounds are mixtures of various isomers (See Figures 2 through 12). Column conditions: Supelcoport
  (100/120 mesh) coated with 3% SP-2250 packed in a 1.8 m long x 2 mm ID glass column with helium carrier gas at
  30 mL/min. flow rate. Column temperature held isothermal at 50  deg.C for 4 min., then programmed at 8  deg.C/
  min. to 270  deg.C and held for 30 min.


  Table 5--Chromatographic Conditions, Method Detection Limits, and Characteristic Masses for Acid Extractables
----------------------------------------------------------------------------------------------------------------
                                                                        Characteristic masses
                              Retention    Method  -------------------------------------------------------------
          Parameter              time    detection          Electron Impact              Chemical ionization
                                (min)      limit   -------------------------------------------------------------
                                         ([mu]g/L)   Primary  Secondary  Secondary   Methane   Methane   Methane
----------------------------------------------------------------------------------------------------------------
2-Chlorophenol..............        5.9        3.3       128         64        130       129       131       157
2-Nitrophenol...............        6.5        3.6       139         65        109       140       168       122
Phenol......................        8.0        1.5        94         65         66        95       123       135
2,4-Dimethylphenol..........        9.4        2.7       122        107        121       123       151       163
2,4-Dichlorophenol..........        9.8        2.7       162        164         98       163       165       167
2,4,6-Trichlorophenol.......       11.8        2.7       196        198        200       197       199       201
4-Chloro-3-methylphenol.....       13.2        3.0       142        107        144       143       171       183
2,4-Dinitrophenol...........       15.9         42       184         63        154       185       213       225
2-Methyl-4,6-dinitrophenol..       16.2         24       198        182         77       199       227       239
Pentachlorophenol...........       17.5        3.6       266        264        268       267       265       269

[[Page 212]]

 
4-Nitrophenol...............       20.3        2.4        65        139        109       140       168       122
----------------------------------------------------------------------------------------------------------------
Column conditions: Supelcoport (100/120 mesh) coated with 1% SP-1240DA packed in a 1.8 m long x 2mm ID glass
  column with helium carrier gas at 30 mL/min. flow rate. Column temperature held isothermal at 70  deg.C for 2
  min. then programmed at 8  deg.C/min. to 200  deg.C.


                                   Table 6--QC Acceptance Criteria--Method 625
----------------------------------------------------------------------------------------------------------------
                                                                  Test                                Range for
                          Parameter                            conclusion   Limits for   Range for      P, Ps
                                                               ([mu]g/L)   s ([mu]g/L)   X([mu]g/L)   (Percent)
----------------------------------------------------------------------------------------------------------------
Acenaphthene................................................          100         27.6   60.1-132.3       47-145
Acenaphthylene..............................................          100         40.2   53.5-126.0       33-145
Aldrin......................................................          100         39.0    7.2-152.2        D-166
Anthracene..................................................          100         32.0   43.4-118.0       27-133
Benzo(a)anthracene..........................................          100         27.6   41.8-133.0       33-143
Benzo(b)fluoranthene........................................          100         38.8   42.0-140.4       24-159
Benzo(k)fluoranthene........................................          100         32.3   25.2-145.7       11-162
Benzo(a)pyrene..............................................          100         39.0   31.7-148.0       17-163
Benzo(ghi)perylene..........................................          100         58.9      D-195.0        D-219
Benzyl butyl phthalate......................................          100         23.4      D-139.9        D-152
[beta]-BHC..................................................          100         31.5   41.5-130.6       24-149
[delta]-BHC.................................................          100         21.6      D-100.0        D-110
Bis(2-chloroethyl) ether....................................          100         55.0   42.9-126.0       12-158
Bis(2-chloroethoxy)methane..................................          100         34.5   49.2-164.7       33-184
Bis(2-chloroisopropyl) ether a..............................          100         46.3   62.8-138.6       36-166
Bis(2-ethylhexyl) phthalate.................................          100         41.1   28.9-136.8        8-158
4-Bromophenyl phenyl ether..................................          100         23.0   64.9-114.4       53-127
2-Chloronaphthalene.........................................          100         13.0   64.5-113.5       60-118
4-Chlorophenyl phenyl ether.................................          100         33.4   38.4-144.7       25-158
Chrysene....................................................          100         48.3   44.1-139.9       17-168
4,4'-DDD....................................................          100         31.0      D-134.5        D-145
4,4'-DDE....................................................          100         32.0   19.2-119.7        4-136
4,4'-DDT....................................................          100         61.6      D-170.6        D-203
Dibenzo(a,h)anthracene......................................          100         70.0      D-199.7        D-227
Di-n-butyl phthalate........................................          100         16.7    8.4-111.0        1-118
1,2-Dichlorobenzene.........................................          100         30.9   48.6-112.0       32-129
1,3-Dichlorobenzene.........................................          100         41.7   16.7-153.9        D-172
1,4,-Dichlorobenzene........................................          100         32.1   37.3-105.7       20-124
3,3'-Dhlorobenzidine........................................          100         71.4    8.2-212.5        D-262
Dieldrin....................................................          100         30.7   44.3-119.3       29-136
Diethyl phthalate...........................................          100         26.5      D-100.0        D-114
Dimethyl phthalate..........................................          100         23.2      D-100.0        D-112
2,4-Dinitrotoluene..........................................          100         21.8   47.5-126.9       39-139
2,6-Dinitrotoluene..........................................          100         29.6   68.1-136.7       50-158
Di-n-octyl phthalate........................................          100         31.4   18.6-131.8        4-146
Endosulfan sulfate..........................................          100         16.7      D-103.5        D-107
Endrin aldehyde.............................................          100         32.5      D-188.8        D-209
Fluoranthene................................................          100         32.8   42.9-121.3       26-137
Fluorene....................................................          100         20.7   71.6-108.4       59-121
Heptachlor..................................................          100         37.2      D-172.2        D-192
Heptachlor epoxide..........................................          100         54.7   70.9-109.4       26-155
Hexachlorobenzene...........................................          100         24.9    7.8-141.5        D-152
Hexachlorobutadiene.........................................          100         26.3   37.8-102.2       24-116
Hexachloroethane............................................          100         24.5   55.2-100.0       40-113
Indeno(1,2,3-cd)pyrene......................................          100         44.6      D-150.9        D-171
Isophorone..................................................          100         63.3   46.6-180.2       21-196
Naphthalene.................................................          100         30.1   35.6-119.6       21-133
Nitrobenzene................................................          100         39.3   54.3-157.6       35-180
N-Nitrosodi-n-propylamine...................................          100         55.4   13.6-197.9        D-230
PCB-1260....................................................          100         54.2   19.3-121.0        D-164
Phenanthrene................................................          100         20.6   65.2-108.7       54-120
Pyrene......................................................          100         25.2   69.6-100.0       52-115
1,2,4-Trichlorobenzene......................................          100         28.1   57.3-129.2       44-142
4-Chloro-3-methylphenol.....................................          100         37.2   40.8-127.9       22-147
2-Chlorophenol..............................................          100         28.7   36.2-120.4       23-134

[[Page 213]]

 
2,4-Dichlorophenol..........................................          100         26.4   52.5-121.7       39-135
2,4-Dimethylphenol..........................................          100         26.1   41.8-109.0       32-119
2,4-Dinitrophenol...........................................          100         49.8      D-172.9        D-191
2-Methyl-4,6-dinitrophenol..................................          100         93.2   53.0-100.0        D-181
2-Nitrophenol...............................................          100         35.2   45.0-166.7       29-182
4-Nitrophenol...............................................          100         47.2   13.0-106.5        D-132
Pentachlorophenol...........................................          100         48.9   38.1-151.8       14-176
Phenol......................................................          100         22.6   16.6-100.0        5-112
2,4,6-Trichlorophenol.......................................          100         31.7   52.4-129.2       37-144
----------------------------------------------------------------------------------------------------------------
s=Standard deviation for four recovery measurements, in [mu]g/L (Section 8.2.4).
X=Average recovery for four recovery measurements, in [mu]g/L (Section 8.2.4).
P, Ps=Percent recovery measured (Section 8.3.2, Section 8.4.2).
D=Detected; result must be greater than zero.
 
Note: These criteria are based directly upon the method performance data in Table 7. Where necessary, the limits
  for recovery have been broadened to assure applicability of the limts to concentrations below those used to
  develop Table 7.
a The proper chemical name is 2,2'oxybis(1-chloropropane).


                Table 7--Method Accuracy and Precision as Functions of Concentration--Method 625
----------------------------------------------------------------------------------------------------------------
                                                                   Accuracy, as   Single analyst      Overall
                            Parameter                              recovery, X'   precision, sr'   precision, S'
                                                                     ([mu]g/L)       ([mu]g/L)       ([mu]g/L)
----------------------------------------------------------------------------------------------------------------
Acenaphthene....................................................      0.96C=0.19      0.15X-0.12      0.21X-0.67
Acenaphthylene..................................................      0.89C=0.74      0.24X-1.06      0.26X-0.54
Aldrin..........................................................      0.78C=1.66      0.27X-1.28      0.43X=1.13
Anthracene......................................................      0.80C=0.68      0.21X-0.32      0.27X-0.64
Benzo(a)anthracene..............................................      0.88C-0.60      0.15X=0.93      0.26X-0.28
Benzo(b)fluoranthene............................................      0.93C-1.80      0.22X=0.43      0.29X=0.96
Benzo(k)fluoranthene............................................      0.87C-1.56      0.19X=1.03      0.35X=0.40
Benzo(a)pyrene..................................................      0.90C-0.13      0.22X=0.48      0.32X=1.35
Benzo(ghi)perylene..............................................      0.98C-0.86      0.29X=2.40      0.51X-0.44
Benzyl butyl phthalate..........................................      0.66C-1.68      0.18X=0.94      0.53X=0.92
[beta]-BHC......................................................      0.87C-0.94      0.20X-0.58      0.30X-1.94
[delta]-BHC.....................................................      0.29C-1.09      0.34X=0.86      0.93X-0.17
Bis(2-chloroethyl) ether........................................      0.86C-1.54      0.35X-0.99      0.35X=0.10
Bis(2-chloroethoxy)methane......................................      1.12C-5.04      0.16X=1.34      0.26X=2.01
Bis(2-chloroisopropyl) ether a..................................      1.03C-2.31      0.24X=0.28      0.25X=1.04
Bis(2-ethylhexyl) phthalate.....................................      0.84C-1.18      0.26X=0.73      0.36X=0.67
4-Bromophenyl phenyl ether......................................      0.91C-1.34      0.13X=0.66      0.16X=0.66
2-Chloronaphthalene.............................................      0.89C=0.01      0.07X=0.52      0.13X=0.34
4-Chlorophenyl phenyl ether.....................................      0.91C=0.53      0.20X-0.94      0.30X-0.46
Chrysene........................................................      0.93C-1.00      0.28X=0.13      0.33X-0.09
4,4'-DDD........................................................      0.56C-0.40      0.29X-0.32      0.66X-0.96
4,4'-DDE........................................................      0.70C-0.54      0.26X-1.17      0.39X-1.04
4,4'-DDT........................................................      0.79C-3.28      0.42X=0.19      0.65X-0.58
Dibenzo(a,h)anthracene..........................................      0.88C=4.72      0.30X=8.51      0.59X=0.25
Di-n-butyl phthalate............................................      0.59C=0.71      0.13X=1.16      0.39X=0.60
1,2-Dichlorobenzene.............................................      0.80C=0.28      0.20X=0.47      0.24X=0.39
1,3-Dichlorobenzene.............................................      0.86C-0.70      0.25X=0.68      0.41X=0.11
1,4-Dichlorobenzene.............................................      0.73C-1.47      0.24X=0.23      0.29X=0.36
3,3'-Dichlorobenzidine..........................................     1.23C-12.65      0.28X=7.33      0.47X=3.45
Dieldrin........................................................      0.82C-0.16      0.20X-0.16      0.26X-0.07
Diethyl phthalate...............................................      0.43C=1.00      0.28X=1.44      0.52X=0.22
Dimethyl phthalate..............................................      0.20C=1.03      0.54X=0.19      1.05X-0.92
2,4-Dinitrotoluene..............................................      0.92C-4.81      0.12X=1.06      0.21X=1.50
2,6-Dinitrotoluene..............................................      1.06C-3.60      0.14X=1.26      0.19X=0.35
Di-n-octyl phthalate............................................      0.76C-0.79      0.21X=1.19      0.37X=1.19
Endosulfan sulfate..............................................      0.39C=0.41      0.12X=2.47      0.63X-1.03
Endrin aldehyde.................................................      0.76C-3.86      0.18X=3.91      0.73X-0.62
Fluoranthene....................................................      0.81C=1.10      0.22X-0.73      0.28X-0.60
Fluorene........................................................      0.90C-0.00      0.12X=0.26      0.13X=0.61
Heptachlor......................................................      0.87C-2.97      0.24X-0.56      0.50X-0.23
Heptachlor epoxide..............................................      0.92C-1.87      0.33X-0.46      0.28X=0.64
Hexachlorobenzene...............................................      0.74C=0.66      0.18X-0.10      0.43X-0.52
Hexachlorobutadiene.............................................      0.71C-1.01      0.19X=0.92      0.26X=0.49
Hexachloroethane................................................      0.73C-0.83      0.17X=0.67      0.17X=0.80
Indeno(1,2,3-cd)pyrene..........................................      0.78C-3.10      0.29X=1.46      0.50X=0.44
Isophorone......................................................      1.12C=1.41      0.27X=0.77      0.33X=0.26
Naphthalene.....................................................      0.76C=1.58      0.21X-0.41      0.30X-0.68

[[Page 214]]

 
Nitrobenzene....................................................      1.09C-3.05      0.19X=0.92      0.27X=0.21
N-Nitrosodi-n-propylamine.......................................      1.12C-6.22      0.27X=0.68      0.44X=0.47
PCB-1260........................................................     0.81C-10.86      0.35X=3.61      0.43X=1.82
Phenanthrene....................................................      0.87C-0.06      0.12X=0.57      0.15X=0.25
Pyrene..........................................................      0.84C-0.16      0.16X=0.06      0.15X=0.31
1,2,4-Trichlorobenzene..........................................      0.94C-0.79      0.15X=0.85      0.21X=0.39
4-Chloro-3-methylphenol.........................................      0.84C=0.35      0.23X=0.75      0.29X=1.31
2-Chlorophenol..................................................      0.78C=0.29      0.18X=1.46      0.28X=0.97
2,4-Dichlorophenol..............................................      0.87C=0.13      0.15X=1.25      0.21X=1.28
2,4-Dimethylphenol..............................................      0.71C=4.41      0.16X=1.21      0.22X=1.31
2,4-Dinitrophenol...............................................     0.81C-18.04      0.38X=2.36     0.42X=26.29
2-Methyl-4,6-Dinitrophenol......................................     1.04C-28.04     0.05X=42.29     0.26X=23.10
2-Nitrophenol...................................................      1.07C-1.15      0.16X=1.94      0.27X=2.60
4-Nitrophenol...................................................      0.61C-1.22      0.38X=2.57      0.44X=3.24
Pentachlorophenol...............................................      0.93C=1.99      0.24X=3.03      0.30X=4.33
Phenol..........................................................      0.43C=1.26      0.26X=0.73      0.35X=0.58
2,4,6-Trichlorophenol...........................................      0.91C-0.18      0.16X=2.22      0.22X=1.81
----------------------------------------------------------------------------------------------------------------
X'=Expected recovery for one or more measurements of a sample containing a concentration of C, in [mu]g/L.
sr'=Expected single analyst standard deviation of measurements at an average concentration found of X, in [mu]g/
  L.
S'= Expected interlaboratory standard deviation of measurements at an average concentration found of X, in [mu]g/
  L.
C= True value for the concentration, in [mu]g/L.
X= Average recovery found for measurements of samples containing a concentration of C, in [mu]g/L.
a The proper chemical name is 2,2'oxybis(1-chloropropane).


           Table 8--Suggested Internal and Surrogate Standards
------------------------------------------------------------------------
           Base/neutral fraction                    Acid fraction
------------------------------------------------------------------------
Aniline-d5................................  2-Fluorophenol.
Anthracene-d10............................  Pentafluorophenol.
Benzo(a)anthracene-d12....................  Phenol-d5
4,4'-Dibromobiphenyl......................  2-Perfluoromethyl phenol.
4,4'-Dibromooctafluorobiphenyl............  ............................
Decafluorobiphenyl........................  ............................
2,2 \1\-Difluorobiphenyl..................  ............................
4-Fluoroaniline...........................  ............................
1-Fluoronaphthalene.......................  ............................
2-Fluoronaphthalene.......................  ............................
Naphthalene-d8............................  ............................
Nitrobenzene-d5...........................  ............................
2,3,4,5,6-Pentafluorobiphenyl.............  ............................
Phenanthrene-d10..........................  ............................
Pyridine-d5...............................  ............................
------------------------------------------------------------------------


            Table 9--DFTPP Key Masses and Abundance Criteria
------------------------------------------------------------------------
  Mass                        m/z Abundance criteria
------------------------------------------------------------------------
     51  30-60 percent of mass 198.
     68  Less than 2 percent of mass 69.
     70  Less than 2 percent of mass 69.
    127  40-60 percent of mass 198.
    197  Less than 1 percent of mass 198.
    198  Base peak, 100 percent relative abundance.
    199  5-9 percent of mass 198.
    275  10-30 percent of mass 198.
    365  Greater than 1 percent of mass 198.
    441  Present but less than mass 443.
    442  Greater than 40 percent of mass 198.
    443  17-23 percent of mass 442.
------------------------------------------------------------------------


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                       Attachment 1 to Method 625

                              Introduction

    To support measurement of several semivolatile pollutants, EPA has 
developed this attachment to EPA Method 625.\1\ The

[[Page 227]]

modifications listed in this attachment are approved only for monitoring 
wastestreams from the Centralized Waste Treatment Point Source Category 
(40 CFR Part 437) and the Landfills Point Source Category (40 CFR Part 
445). EPA Method 625 (the Method) involves sample extraction with 
methylene chloride followed by analysis of the extract using either 
packed or capillary column gas chromatography/mass spectrometry (GC/MS). 
This attachment addresses the addition of the semivolatile pollutants 
listed in Tables 1 and 2, to all applicable standard, stock, and spiking 
solutions utilized for the determination of semivolatile organic 
compounds by EPA Method 625.
---------------------------------------------------------------------------

    \1\ EPA Method 625: Base/Neutrals and Acids, 40 CFR Part 136, 
Appendix A.
---------------------------------------------------------------------------

                1.0  EPA METHOD 625 MODIFICATION SUMMARY

    The additional semivolatile organic compounds listed in Tables 1 and 
2 are added to all applicable calibration, spiking, and other solutions 
utilized in the determination of base/neutral and acid compounds by EPA 
Method 625. The instrument is to be calibrated with these compounds, 
using a capillary column, and all procedures and quality control tests 
stated in the Method must be performed.

                       2.0   SECTION MODIFICATIONS

    Note: All section and figure numbers in this Attachment reference 
section and figure numbers in EPA Method 625 unless noted otherwise. 
Sections not listed here remain unchanged.
Section 6.7  The stock standard solutions described in this section are 
          modified such that the analytes in Tables 1 and 2 of this 
          attachment are required in addition to those specified in the 
          Method.
Section 7.2  The calibration standards described in this section are 
          modified to include the analytes in Tables 1 and 2 of this 
          attachment.
Section 8.2  The precision and accuracy requirements are modified to 
          include the analytes listed in Tables 1 and 2 of this 
          attachment. Additional performance criteria are supplied in 
          Table 5 of this attachment.
Section 8.3  The matrix spike is modified to include the analytes listed 
          in Tables 1 and 2 of this attachment.
Section 8.4  The QC check standard is modified to include the analytes 
          listed in Tables 1 and 2 of this attachment. Additional 
          performance criteria are supplied in Table 5 of this 
          attachment.
Section 16.0  Additional method performance information is supplied with 
          this attachment.

                   Table 1.--Base/Neutral Extractables
------------------------------------------------------------------------
                         Parameter                             CAS No.
------------------------------------------------------------------------
acetophenone 1.............................................      98-86-2
alpha-terpineol 3..........................................      98-55-5
aniline 2..................................................      62-53-3
carbazole 1................................................      86-74-8
o-cresol 1.................................................      95-48-7
n-decane 1.................................................     124-18-5
2,3-dichloroaniline 1......................................     608-27-5
n-octadecane 1.............................................     593-45-3
pyridine 2.................................................    110-86-1
------------------------------------------------------------------------
 CAS = Chemical Abstracts Registry.
1 Analysis of this pollutant is approved only for the Centralized Waste
  Treatment industry.
2 Analysis of this pollutant is approved only for the Centralized Waste
  Treatment and Landfills industries.
3 Analysis of this pollutant is approved only for the Landfills
  industry.


                       Table 2.--Acid Extractables
------------------------------------------------------------------------
                         Parameter                             CAS No.
------------------------------------------------------------------------
p-cresol 1.................................................    106-44-5
------------------------------------------------------------------------
 CAS = Chemical Abstracts Registry.
1 Analysis of this pollutant is approved only for the Centralized Waste
  Treatment and Landfills industries.


   Table 3.--Chromatographic Conditions,\1\ Method Detection Limits (MDLs), and Characteristic m/z's for Base/
                                              Neutral Extractables
----------------------------------------------------------------------------------------------------------------
                                                                                    Characteristic m/z's
                                                  Retention               --------------------------------------
                    Analyte                      time  (min)  MDL  ([mu]g/            Electron impact
                                                     \2\           L)     --------------------------------------
                                                                             Primary     Secondary    Secondary
----------------------------------------------------------------------------------------------------------------
pyridine \3\...................................         4.93          4.6           79           52           51
N-Nitro sodimethylamine........................         4.95  ...........           42           74           44
aniline \3\....................................        10.82          3.3           93           66           65
Bis(2-chloroethyl)ether........................        10.94  ...........           93           63           95
n-decane \4\...................................        11.11          5.0           57  ...........  ...........
1,3-Dichlorobenzene............................        11.47  ...........          146          148          113
1,4-Dichlorobenzene............................        11.62  ...........          146          148          113
1,2-Dichlorobenzene............................        12.17  ...........          146          148          113
o-creso \1\....................................        12.48          4.7          108          107           79
Bis(2-chloro- isopropyl)ether..................        12.51  ...........           45           77           79
acetophenone \4\...............................        12.88          3.4          105           77           51
N-Nitrosodi-n-propylamine......................        12.97  ...........          130           42          101
Hexachloroethane...............................        13.08  ...........          117          201          199
Nitrobenzene...................................        13.40  ...........           77          123           65
Isophorone.....................................        14.11  ...........           82           95          138

[[Page 228]]

 
Bis (2-chloro ethoxy)methane...................        14.82  ...........           93           95          123
1,2,4-Trichlorobenzene.........................        15.37  ...........          180          182          145
alpha-terpineol................................        15.55          5.0           59  ...........  ...........
Naphthalene....................................        15.56  ...........          128          129          127
Hexachlorobutadiene............................        16.12  ...........          225          223          227
Hexachlorocyclopentadiene......................        18.47  ...........          237          235          272
2,3-dichloroaniline \4\........................        18.82          2.5          161          163           90
2-Chloronaphthalene............................        19.35  ...........          162          164          127
Dimethyl phthalate.............................        20.48  ...........          163          194          164
Acenaphthylene.................................        20.69  ...........          152          151          153
2,6-Dinitrotoluene.............................        20.73  ...........          165           89          121
Acenaphthene...................................        21.30  ...........          154          153          152
2,4-Dinitrotoluene.............................        22.00  ...........          165           63          182
Diethylphthalate...............................        22.74  ...........          149          177          150
4-Chlorophenyl phenyl ether....................        22.90  ...........          204          206          141
Fluorene.......................................        22.92  ...........          166          165          167
N-Nitro sodiphenylamine........................        23.35  ...........          169          168          167
4-Bromophenyl phenyl ether.....................        24.44  ...........          248          250          141
Hexachlorobenzene..............................        24.93  ...........          284          142          249
n-octadecane \4\...............................        25.39          2.0           57  ...........  ...........
Phenanthrene...................................        25.98  ...........          178          179          176
Anthracene.....................................        26.12  ...........          178          179          176
Carbazole \4\..................................        26.66          4.0          167  ...........  ...........
Dibutyl phthalate..............................        27.84  ...........          149          150          104
Fluoranthene...................................        29.82  ...........          202          101          100
Benzidine......................................        30.26  ...........          184           92          185
Pyrene.........................................        30.56  ...........          202          101          100
Butyl benzyl phthalate.........................        32.63  ...........          149           91          206
3,3'-Dichlorobenzidine.........................        34.28  ...........          252          254          126
Benzo(a)anthracene.............................        34.33  ...........          228          229          226
Bis(2-ethyl hexyl)phthalate....................        34.36  ...........          149          167          279
Chrysene.......................................        34.44  ...........          228          226          229
Di-n-octyl-phthalate...........................        36.17  ...........          149  ...........  ...........
Benzo(b)fluoranthene...........................        37.90  ...........          252          253          125
Benzo(k)fluoranthene...........................        37.97  ...........          252          253          125
Benzo(a)pyrene.................................        39.17  ...........          252          253          125
Dibenzo(a,h) anthracene........................        44.91  ...........          278          139          279
Indeno(1,2,3-c,d)pyrene........................        45.01  ...........          276          138          277
Benzo(ghi)perylene.............................        46.56  ...........          276          138         277
----------------------------------------------------------------------------------------------------------------
\1\ The data presented in this table were obtained under the following conditions:
 
Column--30 5 meters x 0.25 .02 mm i.d., 94% methyl, 5% phenyl, 1% vinyl, bonded phase
  fused silica capillary column (DB-5).
Temperature program--Five minutes at 30  deg.C; 30-280  deg.C at 8  deg.C per minute; isothermal at 280  deg.C
  until benzo(ghi)perylene elutes.
Gas velocity--305 cm/sec at 30  deg.C.
 
\2\ Retention times are from Method 1625, Revision C, using a capillary column, and are intended to be
  consistent for all analytes in Tables 4 and 5 of this attachment.
\3\ Analysis of this pollutant is approved only for the Centralized Waste Treatment and Landfills industries.
\4\ Analysis of this pollutant is approved only for the Centralized Waste Treatment industry.


   Table 4.--Chromatographic Conditions,\1\ Method Detection Limits (MDLs), and Characteristic m/z's for Acid
                                                  Extractables
----------------------------------------------------------------------------------------------------------------
                                                                                    Characteristic m/z's
                                                  Retention               --------------------------------------
                    Analyte                        time \2\   MDL  ([mu]g/            Electron impact
                                                    (min)          L)     --------------------------------------
                                                                             Primary     Secondary    Secondary
----------------------------------------------------------------------------------------------------------------
Phenol.........................................        10.76  ...........           94           65           66
2-Chlorophenol.................................        11.08  ...........          128           64          130
p-cresol \3\...................................        12.92          7.8          108          107           77
2-Nitrophenol..................................        14.38  ...........          139           65          109
2,4-Dimethylphenol.............................        14.54  ...........          122          107          121
2,4-Dichlorophenol.............................        15.12  ...........          162          164           98
4-Chloro-3-methylphenol........................        16.83  ...........          142          107          144
2,4,6-Trichlorophenol..........................        18.80  ...........          196          198          200
2,4-Dinitrophenol..............................        21.51  ...........          184           63          154

[[Page 229]]

 
4-Nitrophenol..................................        21.77  ...........           65          139          109
2-Methyl-4,6-dinitrophenol.....................        22.83  ...........          198          182           77
Pentachlorophenol..............................        25.52  ...........          266          264         268
----------------------------------------------------------------------------------------------------------------
\1\ The data presented in this table were obtained under the following conditions:
 Column--30 +/-5 meters x 0.25 +/-.02 mm i.d., 94% methyl, 5% phenyl, 1% vinyl silicone bonded phase fused
  silica capillary column (DB-5).
 Temperature program--Five minutes at 30  deg.C; 30-280  deg.C at 8  deg.C per minute; isothermal at 280  deg.C
  until benzo(ghi)perylene elutes.
 Gas velocity--30+/-5 cm/sec at 30  deg.C
\2\ Retention times are from EPA Method 1625, Revision C, using a capillary column, and are intended to be
  consistent for all analytes in Tables 3 and 4 of this attachment.
\3\ Analysis of this pollutant is approved only for the Centralized Waste Treatment and Landfills industries.


                                        Table 5.--QC Acceptance Criteria
----------------------------------------------------------------------------------------------------------------
                                                                Test      Limits for
                          Analyte                            conclusion   s  ([mu]g/  Range for X   Range for
                                                             ([mu]g/L)        L)        ([mu]g/L)    P, Ps(%)
---------------------------------------------------------------------------------------------------------------
acetophenone \1\..........................................          100           51       23-254       61-144
alpha-terpineol...........................................          100           47       46-163       58-156
aniline \2\...............................................          100           71       15-278       46-134
carbazole \1\.............................................          100           17       79-111       73-131
o-cresol \1\..............................................          100           23       30-146       55-126
p-cresol \2\..............................................          100           22       11-617       76-107
n-decane \1\..............................................          100           70        D-651         D-ns
2,3-dichloroaniline \1\...................................          100           13       40-160       68-134
n-octadecane \1\..........................................          100           10       52-147       65-123
pyridine \2\..............................................          100           ns        7-392      33-158
----------------------------------------------------------------------------------------------------------------
 s = Standard deviation for four recovery measurements, in [mu]g/L (Section 8.2)
 X = Average recovery for four recovery measurements in [mu]g/L (Section 8.2)
 P,Ps = Percent recovery measured (Section 8.3, Section 8.4)
 D = Detected; result must be greater than zero.
 ns = no specification; limit is outside the range that can be measured reliably.
\1\ Analysis of this pollutant is approved only for the Centralized Waste Treatment industry.
\2\ Analysis of this pollutant is approved only for the Centralized Waste Treatment and Landfills industries.

                         Method 1613, Revision B

 Tetra- Through Octa-Chlorinated Dioxins and Furans by Isotope Dilution 
                                HRGC/HRMS

                       1.0  Scope and Application

    1.1  This method is for determination of tetra- through octa-
chlorinated dibenzo-p-dioxins (CDDs) and dibenzofurans (CDFs) in water, 
soil, sediment, sludge, tissue, and other sample matrices by high 
resolution gas chromatography/high resolution mass spectrometry (HRGC/
HRMS). The method is for use in EPA's data gathering and monitoring 
programs associated with the Clean Water Act, the Resource Conservation 
and Recovery Act, the Comprehensive Environmental Response, Compensation 
and Liability Act, and the Safe Drinking Water Act. The method is based 
on a compilation of EPA, industry, commercial laboratory, and academic 
methods (References 1-6).
    1.2  The seventeen 2,3,7,8-substituted CDDs/CDFs listed in Table 1 
may be determined by this method. Specifications are also provided for 
separate determination of 2,3,7,8-tetrachloro-dibenzo-p-dioxin (2,3,7,8-
TCDD) and 2,3,7,8-tetrachloro-dibenzofuran (2,3,7,8-TCDF).
    1.3  The detection limits and quantitation levels in this method are 
usually dependent on the level of interferences rather than instrumental 
limitations. The minimum levels (MLs) in Table 2 are the levels at which 
the CDDs/CDFs can be determined with no interferences present. The 
Method Detection Limit (MDL) for 2,3,7,8-TCDD has been determined as 4.4 
pg/L (parts-per-quadrillion) using this method.
    1.4  The GC/MS portions of this method are for use only by analysts 
experienced with HRGC/HRMS or under the close supervision of such 
qualified persons. Each laboratory that uses this method must 
demonstrate the ability to generate acceptable results using the 
procedure in Section 9.2.
    1.5  This method is ``performance-based''. The analyst is permitted 
to modify the method to overcome interferences or lower the cost of 
measurements, provided that all performance criteria in this method are 
met.

[[Page 230]]

The requirements for establishing method equivalency are given in 
Section 9.1.2.
    1.6  Any modification of this method, beyond those expressly 
permitted, shall be considered a major modification subject to 
application and approval of alternate test procedures under 40 CFR 136.4 
and 136.5.

                         2.0  Summary of Method

    Flow charts that summarize procedures for sample preparation, 
extraction, and analysis are given in Figure 1 for aqueous and solid 
samples, Figure 2 for multi-phase samples, and Figure 3 for tissue 
samples.
    2.1  Extraction.
    2.1.1  Aqueous samples (samples containing less than 1% solids)--
Stable isotopically labeled analogs of 15 of the 2,3,7,8-substituted 
CDDs/CDFs are spiked into a 1 L sample, and the sample is extracted by 
one of three procedures:
    2.1.1.1  Samples containing no visible particles are extracted with 
methylene chloride in a separatory funnel or by the solid-phase 
extraction technique summarized in Section 2.1.1.3. The extract is 
concentrated for cleanup.
    2.1.1.2  Samples containing visible particles are vacuum filtered 
through a glass-fiber filter. The filter is extracted in a Soxhlet/Dean-
Stark (SDS) extractor (Reference 7), and the filtrate is extracted with 
methylene chloride in a separatory funnel. The methylene chloride 
extract is concentrated and combined with the SDS extract prior to 
cleanup.
    2.1.1.3  The sample is vacuum filtered through a glass-fiber filter 
on top of a solid-phase extraction (SPE) disk. The filter and disk are 
extracted in an SDS extractor, and the extract is concentrated for 
cleanup.
    2.1.2  Solid, semi-solid, and multi-phase samples (but not tissue)--
The labeled compounds are spiked into a sample containing 10 g (dry 
weight) of solids. Samples containing multiple phases are pressure 
filtered and any aqueous liquid is discarded. Coarse solids are ground 
or homogenized. Any non-aqueous liquid from multi-phase samples is 
combined with the solids and extracted in an SDS extractor. The extract 
is concentrated for cleanup.
    2.1.3  Fish and other tissue--The sample is extracted by one of two 
procedures:
    2.1.3.1  Soxhlet or SDS extraction--A 20 g aliquot of sample is 
homogenized, and a 10 g aliquot is spiked with the labeled compounds. 
The sample is mixed with sodium sulfate, allowed to dry for 12-24 hours, 
and extracted for 18-24 hours using methylene chloride:hexane (1:1) in a 
Soxhlet extractor. The extract is evaporated to dryness, and the lipid 
content is determined.
    2.1.3.2  HCl digestion--A 20 g aliquot is homogenized, and a 10 g 
aliquot is placed in a bottle and spiked with the labeled compounds. 
After equilibration, 200 mL of hydrochloric acid and 200 mL of methylene 
chloride:hexane (1:1) are added, and the bottle is agitated for 12-24 
hours. The extract is evaporated to dryness, and the lipid content is 
determined.
    2.2  After extraction, 37Cl4-labeled 2,3,7,8-
TCDD is added to each extract to measure the efficiency of the cleanup 
process. Sample cleanups may include back-extraction with acid and/or 
base, and gel permeation, alumina, silica gel, Florisil and activated 
carbon chromatography. High-performance liquid chromatography (HPLC) can 
be used for further isolation of the 2,3,7,8-isomers or other specific 
isomers or congeners. Prior to the cleanup procedures cited above, 
tissue extracts are cleaned up using an anthropogenic isolation column, 
a batch silica gel adsorption, or sulfuric acid and base back-
extraction, depending on the tissue extraction procedure used.
    2.3  After cleanup, the extract is concentrated to near dryness. 
Immediately prior to injection, internal standards are added to each 
extract, and an aliquot of the extract is injected into the gas 
chromatograph. The analytes are separated by the GC and detected by a 
high-resolution ([ge]10,000) mass spectrometer. Two exact m/z's are 
monitored for each analyte.
    2.4  An individual CDD/CDF is identified by comparing the GC 
retention time and ion-abundance ratio of two exact m/z's with the 
corresponding retention time of an authentic standard and the 
theoretical or acquired ion-abundance ratio of the two exact m/z's. The 
non-2,3,7,8 substituted isomers and congeners are identified when 
retention times and ion-abundance ratios agree within predefined limits. 
Isomer specificity for 2,3,7,8-TCDD and 2,3,7,8-TCDF is achieved using 
GC columns that resolve these isomers from the other tetra-isomers.
    2.5  Quantitative analysis is performed using selected ion current 
profile (SICP) areas, in one of three ways:
    2.5.1  For the 15 2,3,7,8-substituted CDDs/CDFs with labeled analogs 
(see Table 1), the GC/MS system is calibrated, and the concentration of 
each compound is determined using the isotope dilution technique.
    2.5.2  For 1,2,3,7,8,9-HxCDD, OCDF, and the labeled compounds, the 
GC/MS system is calibrated and the concentration of each compound is 
determined using the internal standard technique.
    2.5.3  For non-2,3,7,8-substituted isomers and for all isomers at a 
given level of chlorination (i.e., total TCDD), concentrations are 
determined using response factors from calibration of the CDDs/CDFs at 
the same level of chlorination.
    2.6  The quality of the analysis is assured through reproducible 
calibration and testing of the extraction, cleanup, and GC/MS systems.

[[Page 231]]

                            3.0  Definitions

    Definitions are given in the glossary at the end of this method.

                  4.0  Contamination and Interferences

    4.1  Solvents, reagents, glassware, and other sample processing 
hardware may yield artifacts and/or elevated baselines causing 
misinterpretation of chromatograms (References 8-9). Specific selection 
of reagents and purification of solvents by distillation in all-glass 
systems may be required. Where possible, reagents are cleaned by 
extraction or solvent rinse.
    4.2  Proper cleaning of glassware is extremely important, because 
glassware may not only contaminate the samples but may also remove the 
analytes of interest by adsorption on the glass surface.
    4.2.1  Glassware should be rinsed with solvent and washed with a 
detergent solution as soon after use as is practical. Sonication of 
glassware containing a detergent solution for approximately 30 seconds 
may aid in cleaning. Glassware with removable parts, particularly 
separatory funnels with fluoropolymer stopcocks, must be disassembled 
prior to detergent washing.
    4.2.2  After detergent washing, glassware should be rinsed 
immediately, first with methanol, then with hot tap water. The tap water 
rinse is followed by another methanol rinse, then acetone, and then 
methylene chloride.
    4.2.3  Do not bake reusable glassware in an oven as a routine part 
of cleaning. Baking may be warranted after particularly dirty samples 
are encountered but should be minimized, as repeated baking of glassware 
may cause active sites on the glass surface that will irreversibly 
adsorb CDDs/CDFs.
    4.2.4  Immediately prior to use, the Soxhlet apparatus should be 
pre-extracted with toluene for approximately three hours (see Sections 
12.3.1 through 12.3.3). Separatory funnels should be shaken with 
methylene chloride/toluene (80/20 mixture) for two minutes, drained, and 
then shaken with pure methylene chloride for two minutes.
    4.3  All materials used in the analysis shall be demonstrated to be 
free from interferences by running reference matrix method blanks 
initially and with each sample batch (samples started through the 
extraction process on a given 12-hour shift, to a maximum of 20 
samples).
    4.3.1  The reference matrix must simulate, as closely as possible, 
the sample matrix under test. Ideally, the reference matrix should not 
contain the CDDs/CDFs in detectable amounts, but should contain 
potential interferents in the concentrations expected to be found in the 
samples to be analyzed. For example, a reference sample of human adipose 
tissue containing pentachloronaphthalene can be used to exercise the 
cleanup systems when samples containing pentachloronaphthalene are 
expected.
    4.3.2  When a reference matrix that simulates the sample matrix 
under test is not available, reagent water (Section 7.6.1) can be used 
to simulate water samples; playground sand (Section 7.6.2) or white 
quartz sand (Section 7.3.2) can be used to simulate soils; filter paper 
(Section 7.6.3) can be used to simulate papers and similar materials; 
and corn oil (Section 7.6.4) can be used to simulate tissues.
    4.4  Interferences coextracted from samples will vary considerably 
from source to source, depending on the diversity of the site being 
sampled. Interfering compounds may be present at concentrations several 
orders of magnitude higher than the CDDs/CDFs. The most frequently 
encountered interferences are chlorinated biphenyls, methoxy biphenyls, 
hydroxydiphenyl ethers, benzylphenyl ethers, polynuclear aromatics, and 
pesticides. Because very low levels of CDDs/CDFs are measured by this 
method, the elimination of interferences is essential. The cleanup steps 
given in Section 13 can be used to reduce or eliminate these 
interferences and thereby permit reliable determination of the CDDs/CDFs 
at the levels shown in Table 2.
    4.5  Each piece of reusable glassware should be numbered to 
associate that glassware with the processing of a particular sample. 
This will assist the laboratory in tracking possible sources of 
contamination for individual samples, identifying glassware associated 
with highly contaminated samples that may require extra cleaning, and 
determining when glassware should be discarded.
    4.6  Cleanup of tissue--The natural lipid content of tissue can 
interfere in the analysis of tissue samples for the CDDs/CDFs. The lipid 
contents of different species and portions of tissue can vary widely. 
Lipids are soluble to varying degrees in various organic solvents and 
may be present in sufficient quantity to overwhelm the column 
chromatographic cleanup procedures used for cleanup of sample extracts. 
Lipids must be removed by the lipid removal procedures in Section 13.7, 
followed by alumina (Section 13.4) or Florisil (Section 13.8), and 
carbon (Section 13.5) as minimum additional cleanup steps. If 
chlorodiphenyl ethers are detected, as indicated by the presence of 
peaks at the exact m/z's monitored for these interferents, alumina and/
or Florisil cleanup must be employed to eliminate these interferences.

                               5.0  Safety

    5.1  The toxicity or carcinogenicity of each compound or reagent 
used in this method has not been precisely determined; however, each 
chemical compound should be

[[Page 232]]

treated as a potential health hazard. Exposure to these compounds should 
be reduced to the lowest possible level.
    5.1.1  The 2,3,7,8-TCDD isomer has been found to be acnegenic, 
carcinogenic, and teratogenic in laboratory animal studies. It is 
soluble in water to approximately 200 ppt and in organic solvents to 
0.14%. On the basis of the available toxicological and physical 
properties of 2,3,7,8-TCDD, all of the CDDs/CDFs should be handled only 
by highly trained personnel thoroughly familiar with handling and 
cautionary procedures and the associated risks.
    5.1.2  It is recommended that the laboratory purchase dilute 
standard solutions of the analytes in this method. However, if primary 
solutions are prepared, they shall be prepared in a hood, and a NIOSH/
MESA approved toxic gas respirator shall be worn when high 
concentrations are handled.
    5.2  The laboratory is responsible for maintaining a current 
awareness file of OSHA regulations regarding the safe handling of the 
chemicals specified in this method. A reference file of material safety 
data sheets (MSDSs) should also be made available to all personnel 
involved in these analyses. It is also suggested that the laboratory 
perform personal hygiene monitoring of each analyst who uses this method 
and that the results of this monitoring be made available to the 
analyst. Additional information on laboratory safety can be found in 
References 10-13. The references and bibliography at the end of 
Reference 13 are particularly comprehensive in dealing with the general 
subject of laboratory safety.
    5.3  The CDDs/CDFs and samples suspected to contain these compounds 
are handled using essentially the same techniques employed in handling 
radioactive or infectious materials. Well-ventilated, controlled access 
laboratories are required. Assistance in evaluating the health hazards 
of particular laboratory conditions may be obtained from certain 
consulting laboratories and from State Departments of Health or Labor, 
many of which have an industrial health service. The CDDs/CDFs are 
extremely toxic to laboratory animals. Each laboratory must develop a 
strict safety program for handling these compounds. The practices in 
References 2 and 14 are highly recommended.
    5.3.1  Facility--When finely divided samples (dusts, soils, dry 
chemicals) are handled, all operations (including removal of samples 
from sample containers, weighing, transferring, and mixing) should be 
performed in a glove box demonstrated to be leak tight or in a fume hood 
demonstrated to have adequate air flow. Gross losses to the laboratory 
ventilation system must not be allowed. Handling of the dilute solutions 
normally used in analytical and animal work presents no inhalation 
hazards except in the case of an accident.
    5.3.2  Protective equipment--Disposable plastic gloves, apron or lab 
coat, safety glasses or mask, and a glove box or fume hood adequate for 
radioactive work should be used. During analytical operations that may 
give rise to aerosols or dusts, personnel should wear respirators 
equipped with activated carbon filters. Eye protection equipment 
(preferably full face shields) must be worn while working with exposed 
samples or pure analytical standards. Latex gloves are commonly used to 
reduce exposure of the hands. When handling samples suspected or known 
to contain high concentrations of the CDDs/CDFs, an additional set of 
gloves can also be worn beneath the latex gloves.
    5.3.3  Training--Workers must be trained in the proper method of 
removing contaminated gloves and clothing without contacting the 
exterior surfaces.
    5.3.4  Personal hygiene--Hands and forearms should be washed 
thoroughly after each manipulation and before breaks (coffee, lunch, and 
shift).
    5.3.5  Confinement--Isolated work areas posted with signs, 
segregated glassware and tools, and plastic absorbent paper on bench 
tops will aid in confining contamination.
    5.3.6  Effluent vapors--The effluents of sample splitters from the 
gas chromatograph (GC) and from roughing pumps on the mass spectrometer 
(MS) should pass through either a column of activated charcoal or be 
bubbled through a trap containing oil or high-boiling alcohols to 
condense CDD/CDF vapors.
    5.3.7  Waste Handling--Good technique includes minimizing 
contaminated waste. Plastic bag liners should be used in waste cans. 
Janitors and other personnel must be trained in the safe handling of 
waste.
    5.3.8  Decontamination
    5.3.8.1  Decontamination of personnel--Use any mild soap with plenty 
of scrubbing action.
    5.3.8.2  Glassware, tools, and surfaces--Chlorothene NU Solvent is 
the least toxic solvent shown to be effective. Satisfactory cleaning may 
be accomplished by rinsing with Chlorothene, then washing with any 
detergent and water. If glassware is first rinsed with solvent, then the 
dish water may be disposed of in the sewer. Given the cost of disposal, 
it is prudent to minimize solvent wastes.
    5.3.9  Laundry--Clothing known to be contaminated should be 
collected in plastic bags. Persons who convey the bags and launder the 
clothing should be advised of the hazard and trained in proper handling. 
The clothing may be put into a washer without contact if the launderer 
knows of the potential problem. The washer should be run through a cycle 
before being used again for other clothing.
    5.3.10  Wipe tests--A useful method of determining cleanliness of 
work surfaces and

[[Page 233]]

tools is to wipe the surface with a piece of filter paper. Extraction 
and analysis by GC with an electron capture detector (ECD) can achieve a 
limit of detection of 0.1 [mu]g per wipe; analysis using this method can 
achieve an even lower detection limit. Less than 0.1 [mu]g per wipe 
indicates acceptable cleanliness; anything higher warrants further 
cleaning. More than 10 [mu]g on a wipe constitutes an acute hazard and 
requires prompt cleaning before further use of the equipment or work 
space, and indicates that unacceptable work practices have been 
employed.
    5.3.11  Table or wrist-action shaker--The use of a table or wrist-
action shaker for extraction of tissues presents the possibility of 
breakage of the extraction bottle and spillage of acid and flammable 
organic solvent. A secondary containment system around the shaker is 
suggested to prevent the spread of acid and solvents in the event of 
such a breakage. The speed and intensity of shaking action should also 
be adjusted to minimize the possibility of breakage.

                      6.0  Apparatus and Materials

    Note: Brand names, suppliers, and part numbers are for illustration 
purposes only and no endorsement is implied. Equivalent performance may 
be achieved using apparatus and materials other than those specified 
here. Meeting the performance requirements of this method is the 
responsibility of the laboratory.

    6.1  Sampling Equipment for Discrete or Composite Sampling
    6.1.1  Sample bottles and caps
    6.1.1.1  Liquid samples (waters, sludges and similar materials 
containing 5% solids or less)--Sample bottle, amber glass, 1.1 L 
minimum, with screw cap.
    6.1.1.2  Solid samples (soils, sediments, sludges, paper pulps, 
filter cake, compost, and similar materials that contain more than 5% 
solids)--Sample bottle, wide mouth, amber glass, 500 mL minimum.
    6.1.1.3  If amber bottles are not available, samples shall be 
protected from light.
    6.1.1.4  Bottle caps--Threaded to fit sample bottles. Caps shall be 
lined with fluoropolymer.
    6.1.1.5  Cleaning
    6.1.1.5.1  Bottles are detergent water washed, then solvent rinsed 
before use.
    6.1.1.5.2  Liners are detergent water washed, rinsed with reagent 
water (Section 7.6.1) followed by solvent, and baked at approximately 
200  deg.C for a minimum of 1 hour prior to use.
    6.1.2  Compositing equipment--Automatic or manual compositing system 
incorporating glass containers cleaned per bottle cleaning procedure 
above. Only glass or fluoropolymer tubing shall be used. If the sampler 
uses a peristaltic pump, a minimum length of compressible silicone 
rubber tubing may be used in the pump only. Before use, the tubing shall 
be thoroughly rinsed with methanol, followed by repeated rinsing with 
reagent water to minimize sample contamination. An integrating flow 
meter is used to collect proportional composite samples.
    6.2  Equipment for Glassware Cleaning--Laboratory sink with overhead 
fume hood.
    6.3  Equipment for Sample Preparation
    6.3.1  Laboratory fume hood of sufficient size to contain the sample 
preparation equipment listed below.
    6.3.2  Glove box (optional).
    6.3.3  Tissue homogenizer--VirTis Model 45 Macro homogenizer 
(American Scientific Products H-3515, or equivalent) with stainless 
steel Macro-shaft and Turbo-shear blade.
    6.3.4  Meat grinder--Hobart, or equivalent, with 3-5 mm holes in 
inner plate.
    6.3.5  Equipment for determining percent moisture
    6.3.5.1  Oven--Capable of maintaining a temperature of 110 
5  deg.C.
    6.3.5.2  Dessicator.
    6.3.6  Balances
    6.3.6.1  Analytical--Capable of weighing 0.1 mg.
    6.3.6.2  Top loading--Capable of weighing 10 mg.
    6.4  Extraction Apparatus
    6.4.1  Water samples
    6.4.1.1  pH meter, with combination glass electrode.
    6.4.1.2  pH paper, wide range (Hydrion Papers, or equivalent).
    6.4.1.3  Graduated cylinder, 1 L capacity.
    6.4.1.4  Liquid/liquid extraction--Separatory funnels, 250 mL, 500 
mL, and 2000 mL, with fluoropolymer stopcocks.
    6.4.1.5  Solid-phase extraction
    6.4.1.5.1  One liter filtration apparatus, including glass funnel, 
glass frit support, clamp, adapter, stopper, filtration flask, and 
vacuum tubing (Figure 4). For wastewater samples, the apparatus should 
accept 90 or 144 mm disks. For drinking water or other samples 
containing low solids, smaller disks may be used.
    6.4.1.5.2  Vacuum source capable of maintaining 25 in. Hg, equipped 
with shutoff valve and vacuum gauge.
    6.4.1.5.3  Glass-fiber filter--Whatman GMF 150 (or equivalent), 1 
micron pore size, to fit filtration apparatus in Section 6.4.1.5.1.
    6.4.1.5.4  Solid-phase extraction disk containing octadecyl 
(C18) bonded silica uniformly enmeshed in an inert matrix--
Fisher Scientific 14-378F (or equivalent), to fit filtration apparatus 
in Section 6.4.1.5.1.
    6.4.2  Soxhlet/Dean-Stark (SDS) extractor (Figure 5)--For filters 
and solid/sludge samples.
    6.4.2.1  Soxhlet--50 mm ID, 200 mL capacity with 500 mL flask (Cal-
Glass LG-6900, or equivalent, except substitute 500 mL round-bottom 
flask for 300 mL flat-bottom flask).

[[Page 234]]

    6.4.2.2  Thimble--43 x 123 to fit Soxhlet (Cal-Glass LG-6901-122, or 
equivalent).
    6.4.2.3  Moisture trap--Dean Stark or Barret with fluoropolymer 
stopcock, to fit Soxhlet.
    6.4.2.4  Heating mantle--Hemispherical, to fit 500 mL round-bottom 
flask (Cal-Glass LG-8801-112, or equivalent).
    6.4.2.5  Variable transformer--Powerstat (or equivalent), 110 volt, 
10 amp.
    6.4.3  Apparatus for extraction of tissue.
    6.4.3.1  Bottle for extraction (if digestion/extraction using HCl is 
used)'' 500-600 mL wide-mouth clear glass, with fluoropolymer-lined cap.
    6.4.3.2  Bottle for back-extraction--100-200 mL narrow-mouth clear 
glass with fluoropolymer-lined cap.
    6.4.3.3  Mechanical shaker--Wrist-action or platform-type rotary 
shaker that produces vigorous agitation (Sybron Thermolyne Model LE 
``Big Bill'' rotator/shaker, or equivalent).
    6.4.3.4  Rack attached to shaker table to permit agitation of four 
to nine samples simultaneously.
    6.4.4  Beakers--400-500 mL.
    6.4.5  Spatulas--Stainless steel.
    6.5  Filtration Apparatus.
    6.5.1  Pyrex glass wool--Solvent-extracted by SDS for three hours 
minimum.

    Note: Baking glass wool may cause active sites that will 
irreversibly adsorb CDDs/CDFs.

    6.5.2  Glass funnel--125-250 mL.
    6.5.3  Glass-fiber filter paper--Whatman GF/D (or equivalent), to 
fit glass funnel in Section 6.5.2.
    6.5.4  Drying column--15-20 mm ID Pyrex chromatographic column 
equipped with coarse-glass frit or glass-wool plug.
    6.5.5  Buchner funnel--15 cm.
    6.5.6  Glass-fiber filter paper--to fit Buchner funnel in Section 
6.5.5.
    6.5.7  Filtration flasks--1.5-2.0 L, with side arm.
    6.5.8  Pressure filtration apparatus--Millipore YT30 142 HW, or 
equivalent.
    6.6  Centrifuge Apparatus.
    6.6.1  Centrifuge--Capable of rotating 500 mL centrifuge bottles or 
15 mL centrifuge tubes at 5,000 rpm minimum.
    6.6.2  Centrifuge bottles--500 mL, with screw-caps, to fit 
centrifuge.
    6.6.3  Centrifuge tubes--12-15 mL, with screw-caps, to fit 
centrifuge.
    6.7  Cleanup Apparatus.
    6.7.1  Automated gel permeation chromatograph (Analytical 
Biochemical Labs, Inc, Columbia, MO, Model GPC Autoprep 1002, or 
equivalent).
    6.7.1.1  Column--600-700 mm long x 25 mm ID, packed with 70 g of
SX-3 Bio-beads (Bio-Rad Laboratories, Richmond, CA, or equivalent).
    6.7.1.2  Syringe--10 mL, with Luer fitting.
    6.7.1.3  Syringe filter holder--stainless steel, and glass-fiber or 
fluoropolymer filters (Gelman 4310, or equivalent).
    6.7.1.4  UV detectors--254 nm, preparative or semi-preparative flow 
cell (Isco, Inc., Type 6; Schmadzu, 5 mm path length; Beckman-Altex 
152W, 8 [mu]L micro-prep flow cell, 2 mm path; Pharmacia UV-1, 3 mm flow 
cell; LDC Milton-Roy UV-3, monitor 1203; or equivalent).
    6.7.2  Reverse-phase high-performance liquid chromatograph.
    6.7.2.1  Column oven and detector--Perkin-Elmer Model LC-65T (or 
equivalent) operated at 0.02 AUFS at 235 nm.
    6.7.2.2  Injector--Rheodyne 7120 (or equivalent) with 50 [mu]L 
sample loop.
    6.7.2.3  Column--Two 6.2 mm x 250 mm Zorbax-ODS columns in series 
(DuPont Instruments Division, Wilmington, DE, or equivalent), operated 
at 50  deg.C with 2.0 mL/min methanol isocratic effluent.
    6.7.2.4  Pump--Altex 110A (or equivalent).
    6.7.3  Pipets.
    6.7.3.1  Disposable, pasteur--150 mm long x 5-mm ID (Fisher 
Scientific 13-678-6A, or equivalent).
    6.7.3.2  Disposable, serological--10 mL (6 mm ID).
    6.7.4  Glass chromatographic columns.
    6.7.4.1  150 mm long x 8-mm ID, (Kontes K-420155, or equivalent) 
with coarse-glass frit or glass-wool plug and 250 mL reservoir.
    6.7.4.2  200 mm long x 15 mm ID, with coarse-glass frit or glass-
wool plug and 250 mL reservoir.
    6.7.4.3  300 mm long x 25 mm ID, with 300 mL reservoir and glass or 
fluoropolymer stopcock.
    6.7.5  Stirring apparatus for batch silica cleanup of tissue 
extracts.
    6.7.5.1  Mechanical stirrer--Corning Model 320, or equivalent.
    6.7.5.2  Bottle--500-600 mL wide-mouth clear glass.
    6.7.6  Oven--For baking and storage of adsorbents, capable of 
maintaining a constant temperature (5  deg.C) in the range 
of 105-250  deg.C.
    6.8  Concentration Apparatus.
    6.8.1  Rotary evaporator--Buchi/Brinkman-American Scientific No. 
E5045-10 or equivalent, equipped with a variable temperature water bath.
    6.8.1.1  Vacuum source for rotary evaporator equipped with shutoff 
valve at the evaporator and vacuum gauge.
    6.8.1.2  A recirculating water pump and chiller are recommended, as 
use of tap water for cooling the evaporator wastes large volumes of 
water and can lead to inconsistent performance as water temperatures and 
pressures vary.
    6.8.1.3  Round-bottom flask--100 mL and 500 mL or larger, with 
ground-glass fitting compatible with the rotary evaporator.
    6.8.2  Kuderna-Danish (K-D) Concentrator.

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    6.8.2.1  Concentrator tube--10 mL, graduated (Kontes K-570050-1025, 
or equivalent) with calibration verified. Ground-glass stopper (size 19/
22 joint) is used to prevent evaporation of extracts.
    6.8.2.2  Evaporation flask--500 mL (Kontes K-570001-0500, or 
equivalent), attached to concentrator tube with springs (Kontes K-
662750-0012 or equivalent).
    6.8.2.3  Snyder column--Three-ball macro (Kontes K-503000-0232, or 
equivalent).
    6.8.2.4  Boiling chips.
    6.8.2.4.1  Glass or silicon carbide--Approximately 10/40 mesh, 
extracted with methylene chloride and baked at 450  deg.C for one hour 
minimum.
    6.8.2.4.2  Fluoropolymer (optional)--Extracted with methylene 
chloride.
    6.8.2.5  Water bath--Heated, with concentric ring cover, capable of 
maintaining a temperature within 2  deg.C, installed in a 
fume hood.
    6.8.3  Nitrogen blowdown apparatus--Equipped with water bath 
controlled in the range of 30-60  deg.C (N-Evap, Organomation 
Associates, Inc., South Berlin, MA, or equivalent), installed in a fume 
hood.
    6.8.4  Sample vials.
    6.8.4.1  Amber glass--2-5 mL with fluoropolymer-lined screw-cap.
    6.8.4.2  Glass--0.3 mL, conical, with fluoropolymer-lined screw or 
crimp cap.
    6.9  Gas Chromatograph--Shall have splitless or on-column injection 
port for capillary column, temperature program with isothermal hold, and 
shall meet all of the performance specifications in Section 10.
    6.9.1  GC column for CDDs/CDFs and for isomer specificity for 
2,3,7,8-TCDD--605 m long x 0.320.02 mm ID; 0.25 
[mu]m 5% phenyl, 94% methyl, 1% vinyl silicone bonded-phase fused-silica 
capillary column (J&W DB-5, or equivalent).
    6.9.2  GC column for isomer specificity for 2,3,7,8-TCDF--
305 m long x 0.320.02 mm ID; 0.25 [mu]m bonded-
phase fused-silica capillary column (J&W DB-225, or equivalent).
    6.10  Mass Spectrometer--28-40 eV electron impact ionization, shall 
be capable of repetitively selectively monitoring 12 exact m/z's minimum 
at high resolution ([ge]10,000) during a period of approximately one 
second, and shall meet all of the performance specifications in Section 
10.
    6.11  GC/MS Interface--The mass spectrometer (MS) shall be 
interfaced to the GC such that the end of the capillary column 
terminates within 1 cm of the ion source but does not intercept the 
electron or ion beams.
    6.12  Data System--Capable of collecting, recording, and storing MS 
data.

                       7.0  Reagents and Standards

    7.1  pH Adjustment and Back-Extraction.
    7.1.1  Potassium hydroxide--Dissolve 20 g reagent grade KOH in 100 
mL reagent water.
    7.1.2  Sulfuric acid--Reagent grade (specific gravity 1.84).
    7.1.3  Hydrochloric acid--Reagent grade, 6N.
    7.1.4  Sodium chloride--Reagent grade, prepare at 5% (w/v) solution 
in reagent water.
    7.2  Solution Drying and Evaporation.
    7.2.1  Solution drying--Sodium sulfate, reagent grade, granular, 
anhydrous (Baker 3375, or equivalent), rinsed with methylene chloride 
(20 mL/g), baked at 400  deg.C for one hour minimum, cooled in a 
dessicator, and stored in a pre-cleaned glass bottle with screw-cap that 
prevents moisture from entering. If, after heating, the sodium sulfate 
develops a noticeable grayish cast (due to the presence of carbon in the 
crystal matrix), that batch of reagent is not suitable for use and 
should be discarded. Extraction with methylene chloride (as opposed to 
simple rinsing) and baking at a lower temperature may produce sodium 
sulfate that is suitable for use.
    7.2.2  Tissue drying--Sodium sulfate, reagent grade, powdered, 
treated and stored as above.
    7.2.3  Prepurified nitrogen.
    7.3  Extraction.
    7.3.1  Solvents--Acetone, toluene, cyclohexane, hexane, methanol, 
methylene chloride, and nonane; distilled in glass, pesticide quality, 
lot-certified to be free of interferences.
    7.3.2  White quartz sand, 60/70 mesh--For Soxhlet/Dean-Stark 
extraction (Aldrich Chemical, Cat. No. 27-437-9, or equivalent). Bake at 
450  deg.C for four hours minimum.
    7.4  GPC Calibration Solution--Prepare a solution containing 300 mg/
mL corn oil, 15 mg/mL bis(2-ethylhexyl) phthalate, 1.4 mg/mL 
pentachlorophenol, 0.1 mg/mL perylene, and 0.5 mg/mL sulfur.
    7.5  Adsorbents for Sample Cleanup.
    7.5.1  Silica gel.
    7.5.1.1  Activated silica gel--100-200 mesh, Supelco 1-3651 (or 
equivalent), rinsed with methylene chloride, baked at 180  deg.C for a 
minimum of one hour, cooled in a dessicator, and stored in a precleaned 
glass bottle with screw-cap that prevents moisture from entering.
    7.5.1.2  Acid silica gel (30% w/w)--Thoroughly mix 44.0 g of 
concentrated sulfuric acid with 100.0 g of activated silica gel in a 
clean container. Break up aggregates with a stirring rod until a uniform 
mixture is obtained. Store in a bottle with a fluoropolymer-lined screw-
cap.
    7.5.1.3  Basic silica gel--Thoroughly mix 30 g of 1N sodium 
hydroxide with 100 g of activated silica gel in a clean container. Break 
up aggregates with a stirring rod until a uniform mixture is obtained. 
Store in a bottle with a fluoropolymer-lined screw-cap.
    7.5.1.4  Potassium silicate.

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    7.5.1.4.1  Dissolve 56 g of high purity potassium hydroxide 
(Aldrich, or equivalent) in 300 mL of methanol in a 750-1000 mL flat-
bottom flask.
    7.5.1.4.2  Add 100 g of silica gel and a stirring bar, and stir on a 
hot plate at 60-70  deg.C for one to two hours.
    7.5.1.4.3  Decant the liquid and rinse the potassium silicate twice 
with 100 mL portions of methanol, followed by a single rinse with 100 mL 
of methylene chloride.
    7.5.1.4.4  Spread the potassium silicate on solvent-rinsed aluminum 
foil and dry for two to four hours in a hood.
    7.5.1.4.5  Activate overnight at 200-250  deg.C.
    7.5.2  Alumina--Either one of two types of alumina, acid or basic, 
may be used in the cleanup of sample extracts, provided that the 
laboratory can meet the performance specifications for the recovery of 
labeled compounds described in Section 9.3. The same type of alumina 
must be used for all samples, including those used to demonstrate 
initial precision and recovery (Section 9.2) and ongoing precision and 
recovery (Section 15.5).
    7.5.2.1  Acid alumina--Supelco 19996-6C (or equivalent). Activate by 
heating to 130  deg.C for a minimum of 12 hours.
    7.5.2.2  Basic alumina--Supelco 19944-6C (or equivalent). Activate 
by heating to 600  deg.C for a minimum of 24 hours. Alternatively, 
activate by heating in a tube furnace at 650-700  deg.C under an air 
flow rate of approximately 400 cc/minute. Do not heat over 700  deg.C, 
as this can lead to reduced capacity for retaining the analytes. Store 
at 130  deg.C in a covered flask. Use within five days of baking.
    7.5.3  Carbon.
    7.5.3.1  Carbopak C--(Supelco 1-0258, or equivalent).
    7.5.3.2  Celite 545--(Supelco 2-0199, or equivalent).
    7.5.3.3  Thoroughly mix 9.0 g Carbopak C and 41.0 g Celite 545 to 
produce an 18% w/w mixture. Activate the mixture at 130  deg.C for a 
minimum of six hours. Store in a dessicator.
    7.5.4  Anthropogenic isolation column--Pack the column in Section 
6.7.4.3 from bottom to top with the following:
    7.5.4.1  2 g silica gel (Section 7.5.1.1).
    7.5.4.2  2 g potassium silicate (Section 7.5.1.4).
    7.5.4.3  2 g granular anhydrous sodium sulfate (Section 7.2.1).
    7.5.4.4  10 g acid silica gel (Section 7.5.1.2).
    7.5.4.5  2 g granular anhydrous sodium sulfate.
    7.5.5  Florisil column.
    7.5.5.1  Florisil--60-100 mesh, Floridin Corp (or equivalent). 
Soxhlet extract in 500 g portions for 24 hours.
    7.5.5.2  Insert a glass wool plug into the tapered end of a 
graduated serological pipet (Section 6.7.3.2). Pack with 1.5 g (approx 2 
mL) of Florisil topped with approx 1 mL of sodium sulfate (Section 
7.2.1) and a glass wool plug.
    7.5.5.3  Activate in an oven at 130-150  deg.C for a minimum of 24 
hours and cool for 30 minutes. Use within 90 minutes of cooling.
    7.6  Reference Matrices--Matrices in which the CDDs/CDFs and 
interfering compounds are not detected by this method.
    7.6.1  Reagent water--Bottled water purchased locally, or prepared 
by passage through activated carbon.
    7.6.2  High-solids reference matrix--Playground sand or similar 
material. Prepared by extraction with methylene chloride and/or baking 
at 450  deg.C for a minimum of four hours.
    7.6.3  Paper reference matrix--Glass-fiber filter, Gelman Type A, or 
equivalent. Cut paper to simulate the surface area of the paper sample 
being tested.
    7.6.4  Tissue reference matrix--Corn or other vegetable oil. May be 
prepared by extraction with methylene chloride.
    7.6.5  Other matrices--This method may be verified on any reference 
matrix by performing the tests given in Section 9.2. Ideally, the matrix 
should be free of the CDDs/CDFs, but in no case shall the background 
level of the CDDs/CDFs in the reference matrix exceed three times the 
minimum levels in Table 2. If low background levels of the CDDs/CDFs are 
present in the reference matrix, the spike level of the analytes used in 
Section 9.2 should be increased to provide a spike-to-background ratio 
in the range of 1:1 to 5:1 (Reference 15).
    7.7  Standard Solutions--Purchased as solutions or mixtures with 
certification to their purity, concentration, and authenticity, or 
prepared from materials of known purity and composition. If the chemical 
purity is 98% or greater, the weight may be used without correction to 
compute the concentration of the standard. When not being used, 
standards are stored in the dark at room temperature in screw-capped 
vials with fluoropolymer-lined caps. A mark is placed on the vial at the 
level of the solution so that solvent loss by evaporation can be 
detected. If solvent loss has occurred, the solution should be replaced.
    7.8  Stock Solutions.
    7.8.1  Preparation--Prepare in nonane per the steps below or 
purchase as dilute solutions (Cambridge Isotope Laboratories (CIL), 
Woburn, MA, or equivalent). Observe the safety precautions in Section 5, 
and the recommendation in Section 5.1.2.
    7.8.2  Dissolve an appropriate amount of assayed reference material 
in solvent. For example, weigh 1-2 mg of 2,3,7,8-TCDD to three 
significant figures in a 10 mL ground-glass-stoppered volumetric flask 
and fill to the mark with nonane. After the TCDD is completely 
dissolved, transfer the solution to a clean 15 mL vial with 
fluoropolymer-lined cap.
    7.8.3  Stock standard solutions should be checked for signs of 
degradation prior to the

[[Page 237]]

preparation of calibration or performance test standards. Reference 
standards that can be used to determine the accuracy of calibration 
standards are available from CIL and may be available from other 
vendors.
    7.9  PAR Stock Solution
    7.9.1  All CDDs/CDFs--Using the solutions in Section 7.8, prepare 
the PAR stock solution to contain the CDDs/CDFs at the concentrations 
shown in Table 3. When diluted, the solution will become the PAR 
(Section 7.14).
    7.9.2  If only 2,3,7,8-TCDD and 2,3,7,8-TCDF are to be determined, 
prepare the PAR stock solution to contain these compounds only.
    7.10  Labeled-Compound Spiking Solution.
    7.10.1  All CDDs/CDFs--From stock solutions, or from purchased 
mixtures, prepare this solution to contain the labeled compounds in 
nonane at the concentrations shown in Table 3. This solution is diluted 
with acetone prior to use (Section 7.10.3).
    7.10.2  If only 2,3,7,8-TCDD and 2,3,7,8-TCDF are to be determined, 
prepare the labeled-compound solution to contain these compounds only. 
This solution is diluted with acetone prior to use (Section 7.10.3).
    7.10.3  Dilute a sufficient volume of the labeled compound solution 
(Section 7.10.1 or 7.10.2) by a factor of 50 with acetone to prepare a 
diluted spiking solution. Each sample requires 1.0 mL of the diluted 
solution, but no more solution should be prepared than can be used in 
one day.
    7.11  Cleanup Standard--Prepare 37Cl4-2,3,7,8-
TCDD in nonane at the concentration shown in Table 3. The cleanup 
standard is added to all extracts prior to cleanup to measure the 
efficiency of the cleanup process.
    7.12  Internal Standard(s).
    7.12.1  All CDDs/CDFs--Prepare the internal standard solution to 
contain 13C12-1,2,3,4-TCDD and 
13C2-1,2,3,7,8,9-HxCDD in nonane at the 
concentration shown in Table 3.
    7.12.2  If only 2,3,7,8-TCDD and 2,3,7,8-TCDF are to be determined, 
prepare the internal standard solution to contain 
13C12-1,2,3,4-TCDD only.
    7.13  Calibration Standards (CS1 through CS5)--Combine the solutions 
in Sections 7.9 through 7.12 to produce the five calibration solutions 
shown in Table 4 in nonane. These solutions permit the relative response 
(labeled to native) and response factor to be measured as a function of 
concentration. The CS3 standard is used for calibration verification 
(VER). If only 2,3,7,8-TCDD and 2,3,7,8-TCDF are to be determined, 
combine the solutions appropriate to these compounds.
    7.14  Precision and Recovery (PAR) Standard--Used for determination 
of initial (Section 9.2) and ongoing (Section 15.5) precision and 
recovery. Dilute 10 [mu]L of the precision and recovery standard 
(Section 7.9.1 or 7.9.2) to 2.0 mL with acetone for each sample matrix 
for each sample batch. One mL each are required for the blank and OPR 
with each matrix in each batch.
    7.15  GC Retention Time Window Defining Solution and Isomer 
Specificity Test Standard--Used to define the beginning and ending 
retention times for the dioxin and furan isomers and to demonstrate 
isomer specificity of the GC columns employed for determination of 
2,3,7,8-TCDD and 2,3,7,8-TCDF. The standard must contain the compounds 
listed in Table 5 (CIL EDF--4006, or equivalent), at a minimum. It is 
not necessary to monitor the window-defining compounds if only 2,3,7,8-
TCDD and 2,3,7,8-TCDF are to be determined. In this case, an isomer-
specificity test standard containing the most closely eluted isomers 
listed in Table 5 (CIL EDF-4033, or equivalent) may be used.
    7.16  QC Check Sample--A QC Check Sample should be obtained from a 
source independent of the calibration standards. Ideally, this check 
sample would be a certified reference material containing the CDDs/CDFs 
in known concentrations in a sample matrix similar to the matrix under 
test.
    7.17  Stability of Solutions--Standard solutions used for 
quantitative purposes (Sections 7.9 through 7.15) should be analyzed 
periodically, and should be assayed against reference standards (Section 
7.8.3) before further use.

    8.0  Sample Collection, Preservation, Storage, and Holding Times

    8.1  Collect samples in amber glass containers following 
conventional sampling practices (Reference 16). Aqueous samples that 
flow freely are collected in refrigerated bottles using automatic 
sampling equipment. Solid samples are collected as grab samples using 
wide-mouth jars.
    8.2  Maintain aqueous samples in the dark at 0-4  deg.C from the 
time of collection until receipt at the laboratory. If residual chlorine 
is present in aqueous samples, add 80 mg sodium thiosulfate per liter of 
water. EPA Methods 330.4 and 330.5 may be used to measure residual 
chlorine (Reference 17). If sample pH is greater than 9, adjust to pH 7-
9 with sulfuric acid.
    Maintain solid, semi-solid, oily, and mixed-phase samples in the 
dark at <4  deg.C from the time of collection until receipt at the 
laboratory.
    Store aqueous samples in the dark at 0-4  deg.C. Store solid, semi-
solid, oily, mixed-phase, and tissue samples in the dark at <-10  deg.C.
    8.3  Fish and Tissue Samples.
    8.3.1  Fish may be cleaned, filleted, or processed in other ways in 
the field, such that the laboratory may expect to receive whole fish, 
fish fillets, or other tissues for analysis.
    8.3.2  Fish collected in the field should be wrapped in aluminum 
foil, and must be maintained at a temperature less than 4  deg.C

[[Page 238]]

from the time of collection until receipt at the laboratory.
    8.3.3  Samples must be frozen upon receipt at the laboratory and 
maintained in the dark at <-10  deg.C until prepared. Maintain unused 
sample in the dark at <-10  deg.C.
    8.4  Holding Times.
    8.4.1  There are no demonstrated maximum holding times associated 
with CDDs/CDFs in aqueous, solid, semi-solid, tissues, or other sample 
matrices. If stored in the dark at 0-4  deg.C and preserved as given 
above (if required), aqueous samples may be stored for up to one year. 
Similarly, if stored in the dark at <-10  deg.C, solid, semi-solid, 
multi-phase, and tissue samples may be stored for up to one year.
    8.4.2  Store sample extracts in the dark at <-10  deg.C until 
analyzed. If stored in the dark at <-10  deg.C, sample extracts may be 
stored for up to one year.

                 9.0  Quality Assurance/Quality Control

    9.1  Each laboratory that uses this method is required to operate a 
formal quality assurance program (Reference 18). The minimum 
requirements of this program consist of an initial demonstration of 
laboratory capability, analysis of samples spiked with labeled compounds 
to evaluate and document data quality, and analysis of standards and 
blanks as tests of continued performance. Laboratory performance is 
compared to established performance criteria to determine if the results 
of analyses meet the performance characteristics of the method.
    If the method is to be applied to sample matrix other than water 
(e.g., soils, filter cake, compost, tissue) the most appropriate 
alternate matrix (Sections 7.6.2 through 7.6.5) is substituted for the 
reagent water matrix (Section 7.6.1) in all performance tests.
    9.1.1  The analyst shall make an initial demonstration of the 
ability to generate acceptable accuracy and precision with this method. 
This ability is established as described in Section 9.2.
    9.1.2  In recognition of advances that are occurring in analytical 
technology, and to allow the analyst to overcome sample matrix 
interferences, the analyst is permitted certain options to improve 
separations or lower the costs of measurements. These options include 
alternate extraction, concentration, cleanup procedures, and changes in 
columns and detectors. Alternate determinative techniques, such as the 
substitution of spectroscopic or immuno-assay techniques, and changes 
that degrade method performance, are not allowed. If an analytical 
technique other than the techniques specified in this method is used, 
that technique must have a specificity equal to or better than the 
specificity of the techniques in this method for the analytes of 
interest.
    9.1.2.1  Each time a modification is made to this method, the 
analyst is required to repeat the procedure in Section 9.2. If the 
detection limit of the method will be affected by the change, the 
laboratory is required to demonstrate that the MDL (40 CFR Part 136, 
Appendix B) is lower than one-third the regulatory compliance level or 
one-third the ML in this method, whichever is higher. If calibration 
will be affected by the change, the analyst must recalibrate the 
instrument per Section 10.
    9.1.2.2  The laboratory is required to maintain records of 
modifications made to this method. These records include the following, 
at a minimum:
    9.1.2.2.1  The names, titles, addresses, and telephone numbers of 
the analyst(s) who performed the analyses and modification, and of the 
quality control officer who witnessed and will verify the analyses and 
modifications.
    9.1.2.2.2  A listing of pollutant(s) measured, by name and CAS 
Registry number.
    9.1.2.2.3  A narrative stating reason(s) for the modifications.
    9.1.2.2.4  Results from all quality control (QC) tests comparing the 
modified method to this method, including:
    (a) Calibration (Section 10.5 through 10.7).
    (b) Calibration verification (Section 15.3).
    (c) Initial precision and recovery (Section 9.2).
    (d) Labeled compound recovery (Section 9.3).
    (e) Analysis of blanks (Section 9.5).
    (f) Accuracy assessment (Section 9.4).
    9.1.2.2.5  Data that will allow an independent reviewer to validate 
each determination by tracing the instrument output (peak height, area, 
or other signal) to the final result. These data are to include:
    (a) Sample numbers and other identifiers.
    (b) Extraction dates.
    (c) Analysis dates and times.
    (d) Analysis sequence/run chronology.
    (e) Sample weight or volume (Section 11).
    (f) Extract volume prior to each cleanup step (Section 13).
    (g) Extract volume after each cleanup step (Section 13).
    (h) Final extract volume prior to injection (Section 14).
    (i) Injection volume (Section 14.3).
    (j) Dilution data, differentiating between dilution of a sample or 
extract (Section 17.5).
    (k) Instrument and operating conditions.
    (l) Column (dimensions, liquid phase, solid support, film thickness, 
etc).
    (m) Operating conditions (temperatures, temperature program, flow 
rates).
    (n) Detector (type, operating conditions, etc).
    (o) Chromatograms, printer tapes, and other recordings of raw data.
    (p) Quantitation reports, data system outputs, and other data to 
link the raw data to the results reported.

[[Page 239]]

    9.1.3  Analyses of method blanks are required to demonstrate freedom 
from contamination (Section 4.3). The procedures and criteria for 
analysis of a method blank are described in Sections 9.5 and 15.6.
    9.1.4  The laboratory shall spike all samples with labeled compounds 
to monitor method performance. This test is described in Section 9.3. 
When results of these spikes indicate atypical method performance for 
samples, the samples are diluted to bring method performance within 
acceptable limits. Procedures for dilution are given in Section 17.5.
    9.1.5  The laboratory shall, on an ongoing basis, demonstrate 
through calibration verification and the analysis of the ongoing 
precision and recovery aliquot that the analytical system is in control. 
These procedures are described in Sections 15.1 through 15.5.
    9.1.6  The laboratory shall maintain records to define the quality 
of data that is generated. Development of accuracy statements is 
described in Section 9.4.
    9.2  Initial Precision and Recovery (IPR)--To establish the ability 
to generate acceptable precision and recovery, the analyst shall perform 
the following operations.
    9.2.1  For low solids (aqueous) samples, extract, concentrate, and 
analyze four 1 L aliquots of reagent water spiked with the diluted 
labeled compound spiking solution (Section 7.10.3) and the precision and 
recovery standard (Section 7.14) according to the procedures in Sections 
11 through 18. For an alternative sample matrix, four aliquots of the 
alternative reference matrix (Section 7.6) are used. All sample 
processing steps that are to be used for processing samples, including 
preparation (Section 11), extraction (Section 12), and cleanup (Section 
13), shall be included in this test.
    9.2.2  Using results of the set of four analyses, compute the 
average concentration (X) of the extracts in ng/mL and the standard 
deviation of the concentration (s) in ng/mL for each compound, by 
isotope dilution for CDDs/CDFs with a labeled analog, and by internal 
standard for 1,2,3,7,8,9-HxCDD, OCDF, and the labeled compounds.
    9.2.3  For each CDD/CDF and labeled compound, compare s and X with 
the corresponding limits for initial precision and recovery in Table 6. 
If only 2,3,7,8-TCDD and 2,3,7,8-TCDF are to be determined, compare s 
and X with the corresponding limits for initial precision and recovery 
in Table 6a. If s and X for all compounds meet the acceptance criteria, 
system performance is acceptable and analysis of blanks and samples may 
begin. If, however, any individual s exceeds the precision limit or any 
individual X falls outside the range for accuracy, system performance is 
unacceptable for that compound. Correct the problem and repeat the test 
(Section 9.2).
    9.3  The laboratory shall spike all samples with the diluted labeled 
compound spiking solution (Section 7.10.3) to assess method performance 
on the sample matrix.
    9.3.1  Analyze each sample according to the procedures in Sections 
11 through 18.
    9.3.2  Compute the percent recovery of the labeled compounds and the 
cleanup standard using the internal standard method (Section 17.2).
    9.3.3  The recovery of each labeled compound must be within the 
limits in Table 7 when all 2,3,7,8-substituted CDDs/CDFs are determined, 
and within the limits in Table 7a when only 2,3,7,8-TCDD and 2,3,7,8-
TCDF are determined. If the recovery of any compound falls outside of 
these limits, method performance is unacceptable for that compound in 
that sample. To overcome such difficulties, water samples are diluted 
and smaller amounts of soils, sludges, sediments, and other matrices are 
reanalyzed per Section 18.4.
    9.4  Recovery of labeled compounds from samples should be assessed 
and records should be maintained.
    9.4.1  After the analysis of five samples of a given matrix type 
(water, soil, sludge, pulp, etc.) for which the labeled compounds pass 
the tests in Section 9.3, compute the average percent recovery (R) and 
the standard deviation of the percent recovery (SR) for the labeled 
compounds only. Express the assessment as a percent recovery interval 
from R-2SR to R=2SR for each matrix. For example, 
if R = 90% and SR = 10% for five analyses of pulp, the 
recovery interval is expressed as 70-110%.
    9.4.2  Update the accuracy assessment for each labeled compound in 
each matrix on a regular basis (e.g., after each 5-10 new measurements).
    9.5  Method Blanks--Reference matrix method blanks are analyzed to 
demonstrate freedom from contamination (Section 4.3).
    9.5.1  Prepare, extract, clean up, and concentrate a method blank 
with each sample batch (samples of the same matrix started through the 
extraction process on the same 12-hour shift, to a maximum of 20 
samples). The matrix for the method blank shall be similar to sample 
matrix for the batch, e.g., a 1 L reagent water blank (Section 7.6.1), 
high-solids reference matrix blank (Section 7.6.2), paper matrix blank 
(Section 7.6.3); tissue blank (Section 7.6.4) or alternative reference 
matrix blank (Section 7.6.5). Analyze the blank immediately after 
analysis of the OPR (Section 15.5) to demonstrate freedom from 
contamination.
    9.5.2  If any 2,3,7,8-substituted CDD/CDF (Table 1) is found in the 
blank at greater than the minimum level (Table 2) or one-third the 
regulatory compliance level, whichever is greater; or if any potentially 
interfering compound is found in the blank at the minimum level for each 
level of

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chlorination given in Table 2 (assuming a response factor of 1 relative 
to the 13C12-1,2,3,4-TCDD internal standard for 
compounds not listed in Table 1), analysis of samples is halted until 
the blank associated with the sample batch shows no evidence of 
contamination at this level. All samples must be associated with an 
uncontaminated method blank before the results for those samples may be 
reported for regulatory compliance purposes.
    9.6  QC Check Sample--Analyze the QC Check Sample (Section 7.16) 
periodically to assure the accuracy of calibration standards and the 
overall reliability of the analytical process. It is suggested that the 
QC Check Sample be analyzed at least quarterly.
    9.7  The specifications contained in this method can be met if the 
apparatus used is calibrated properly and then maintained in a 
calibrated state. The standards used for calibration (Section 10), 
calibration verification (Section 15.3), and for initial (Section 9.2) 
and ongoing (Section 15.5) precision and recovery should be identical, 
so that the most precise results will be obtained. A GC/MS instrument 
will provide the most reproducible results if dedicated to the settings 
and conditions required for the analyses of CDDs/CDFs by this method.
    9.8  Depending on specific program requirements, field replicates 
may be collected to determine the precision of the sampling technique, 
and spiked samples may be required to determine the accuracy of the 
analysis when the internal standard method is used.

                            10.0  Calibration

    10.1  Establish the operating conditions necessary to meet the 
minimum retention times for the internal standards in Section 10.2.4 and 
the relative retention times for the CDDs/CDFs in Table 2.
    10.1.1  Suggested GC operating conditions:

Injector temperature: 270  deg.C
Interface temperature: 290  deg.C
Initial temperature: 200  deg.C
Initial time: Two minutes
Temperature program:
200-220  deg.C, at 5  deg.C/minute
220  deg.C for 16 minutes
220-235  deg.C, at 5  deg.C/minute
235  deg.C for seven minutes
235-330  deg.C, at 5  deg.C/minute

    Note: All portions of the column that connect the GC to the ion 
source shall remain at or above the interface temperature specified 
above during analysis to preclude condensation of less volatile 
compounds.

    Optimize GC conditions for compound separation and sensitivity. Once 
optimized, the same GC conditions must be used for the analysis of all 
standards, blanks, IPR and OPR aliquots, and samples.
    10.1.2  Mass spectrometer (MS) resolution--Obtain a selected ion 
current profile (SICP) of each analyte in Table 3 at the two exact m/z's 
specified in Table 8 and at [ge]10,000 resolving power by injecting an 
authentic standard of the CDDs/CDFs either singly or as part of a 
mixture in which there is no interference between closely eluted 
components.
    10.1.2.1  The analysis time for CDDs/CDFs may exceed the long-term 
mass stability of the mass spectrometer. Because the instrument is 
operated in the high-resolution mode, mass drifts of a few ppm (e.g., 5 
ppm in mass) can have serious adverse effects on instrument performance. 
Therefore, a mass-drift correction is mandatory and a lock-mass m/z from 
PFK is used for drift correction. The lock-mass m/z is dependent on the 
exact m/z's monitored within each descriptor, as shown in Table 8. The 
level of PFK metered into the HRMS during analyses should be adjusted so 
that the amplitude of the most intense selected lock-mass m/z signal 
(regardless of the descriptor number) does not exceed 10% of the full-
scale deflection for a given set of detector parameters. Under those 
conditions, sensitivity changes that might occur during the analysis can 
be more effectively monitored.

    Note: Excessive PFK (or any other reference substance) may cause 
noise problems and contamination of the ion source necessitating 
increased frequency of source cleaning.

    10.1.2.2  If the HRMS has the capability to monitor resolution 
during the analysis, it is acceptable to terminate the analysis when the 
resolution falls below 10,000 to save reanalysis time.
    10.1.2.3  Using a PFK molecular leak, tune the instrument to meet 
the minimum required resolving power of 10,000 (10% valley) at m/z 
304.9824 (PFK) or any other reference signal close to m/z 304 (from 
TCDF). For each descriptor (Table 8), monitor and record the resolution 
and exact m/z's of three to five reference peaks covering the mass range 
of the descriptor. The resolution must be greater than or equal to 
10,000, and the deviation between the exact m/z and the theoretical m/z 
(Table 8) for each exact m/z monitored must be less than 5 ppm.
    10.2  Ion Abundance Ratios, Minimum Levels, Signal-to-Noise Ratios, 
and Absolute Retention Times--Choose an injection volume of either 1 
[mu]L or 2 [mu]L, consistent with the capability of the HRGC/HRMS 
instrument. Inject a 1 [mu]L or 2 [mu]L aliquot of the CS1 calibration 
solution (Table 4) using the GC conditions from Section 10.1.1. If only 
2,3,7,8-TCDD and 2,3,7,8-TCDF are to be determined, the operating 
conditions and specifications below apply to analysis of those compounds 
only.

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    10.2.1  Measure the SICP areas for each analyte, and compute the ion 
abundance ratios at the exact m/z's specified in Table 8. Compare the 
computed ratio to the theoretical ratio given in Table 9.
    10.2.1.1  The exact m/z's to be monitored in each descriptor are 
shown in Table 8. Each group or descriptor shall be monitored in 
succession as a function of GC retention time to ensure that all CDDs/
CDFs are detected. Additional m/z's may be monitored in each descriptor, 
and the m/z's may be divided among more than the five descriptors listed 
in Table 8, provided that the laboratory is able to monitor the m/z's of 
all the CDDs/CDFs that may elute from the GC in a given retention-time 
window. If only 2,3,7,8-TCDD and 2,3,7,8-TCDF are to be determined, the 
descriptors may be modified to include only the exact m/z's for the 
tetra-and penta-isomers, the diphenyl ethers, and the lock m/z's.
    10.2.1.2  The mass spectrometer shall be operated in a mass-drift 
correction mode, using perfluorokerosene (PFK) to provide lock m/z's. 
The lock-mass for each group of m/z's is shown in Table 8. Each lock 
mass shall be monitored and shall not vary by more than 20% 
throughout its respective retention time window. Variations of the lock 
mass by more than 20% indicate the presence of coeluting interferences 
that may significantly reduce the sensitivity of the mass spectrometer. 
Reinjection of another aliquot of the sample extract will not resolve 
the problem. Additional cleanup