[Federal Register Volume 63, Number 147 (Friday, July 31, 1998)]
[Proposed Rules]
[Pages 41134-41143]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-20281]



[[Page 41133]]

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Part III





Environmental Protection Agency





_______________________________________________________________________



40 CFR Part 141



National Primary Drinking Water Regulations: Analytical Methods for 
Certain Pesticides and Microbial Contaminants; Proposed Rule

Federal Register / Vol. 63, No. 147 / Friday, July 31, 1998 / 
Proposed Rules

[[Page 41134]]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 141

[WH-FRL-6132-3]
RIN 2040-AD04


National Primary Drinking Water Regulations: Analytical Methods 
for Certain Pesticides and Microbial Contaminants

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: EPA is proposing to approve the use of a new membrane filter 
medium for the simultaneous detection of total coliform and Escherichia 
coli (E. coli) and three revised chemical analytical methods for 
compliance determinations of acid herbicides and diquat in drinking 
water. The Agency proposes to withdraw approval of the previous version 
of the EPA Method for diquat. The Agency is also proposing to amend and 
clarify laboratory certification requirements, and to amend the 
regulations to make the current recommendation to ship microbiological 
samples below 10  deg.C a requirement. The purpose of the proposal is 
to approve new methods, withdraw an outdated EPA method, clarify 
laboratory certification requirements and improve the reliability of 
sample collection for total or fecal coliform. The rule is expected to 
satisfy public requests for approval of new technologies in drinking 
water analyses.

DATES: Comments on this proposed rule must be received in writing by 
September 29, 1998.

ADDRESSES: Written or electronic comments on this proposed rule may be 
submitted. Written comments may be sent to the W-97-05 Drinking Water 
Analytical Methods Proposed Comment Clerk, U.S. Environmental 
Protection Agency, Water Docket, MC 4101, 401 M Street, SW, Washington, 
DC 20460. Please submit any references cited in your comments. EPA 
would appreciate an original and 3 copies of your comments and 
enclosures (including references).
    No facsimiles (faxes) will be accepted because EPA cannot ensure 
that they will be submitted to the Water Docket. To ensure that EPA can 
read, understand and therefore properly respond to comments, the Agency 
would prefer that commenters cite, where possible, the paragraph(s) in 
the proposed regulation (e.g., 141.24(e)) to which each comment refers. 
Commenters should use a separate paragraph for each method or issue 
discussed. Commenters who would like acknowledgment of receipt of their 
comments should include a self-addressed, stamped envelope. For 
information on submitting comments electronically see Supplementary 
Information.
    The record for this rulemaking has been established under docket 
number W-97-05. Copies of the supporting documents (including 
references and methods cited in this notice) are available for review 
at the U.S. Environmental Protection Agency, Water Docket, East Tower 
Basement, 401 M Street, SW, Washington, DC 20460. For access to the 
docket materials, call 202-260-3027 on Monday through Friday, excluding 
Federal holidays, between 9:00 a.m. and 3:30 p.m. Eastern Time for an 
appointment.

FOR FURTHER INFORMATION CONTACT: Ms. Jeanne Campbell, Standards and 
Risk Management Division, Office of Ground Water and Drinking Water 
(MC-4607), U.S. Environmental Protection Agency, 401 M Street, SW, 
Washington, DC 20460, telephone 202-260-7770. General information may 
also be obtained from the EPA Safe Drinking Water Hotline. Callers 
within the United States may reach the Hotline at 800-426-4791. The 
Hotline is open Monday through Friday, excluding Federal holidays, from 
9 a.m. to 5:30 p.m. Eastern Time.
    For technical information regarding microbiology methods, contact 
Paul S. Berger, Ph.D., Office of Ground Water and Drinking Water (MC-
4607), U.S. Environmental Protection Agency, Washington, DC 20460, 
telephone 202-260-3039. For technical information regarding chemistry 
methods, contact Richard Reding, Ph.D., Office of Ground Water and 
Drinking Water, U.S. Environmental Protection Agency, Cincinnati, Ohio 
45268, telephone 513-569-7961. For a list of Regional Contacts see 
Supplementary Information.

SUPPLEMENTARY INFORMATION:

Potentially Regulated Entities

    EPA Regions, as well as States, Territories, and Tribes with 
primacy to administer the regulatory program for public water systems 
under the Safe Drinking Water Act, sometimes conduct analyses to 
measure for contaminants in water samples, but often require the public 
water systems themselves to conduct such analysis. If EPA has 
established a maximum contaminant level (``MCL'') for a given drinking 
water contaminant, the Agency also ``approves'' standardized testing 
procedures (i.e., promulgated through rulemaking) for analysis of the 
contaminant. Once EPA standardizes such test procedures, analysis using 
those procedures (or approved alternate test procedures) is required. 
Therefore, States, Territories, Tribes, and public water systems 
required to test water samples are potentially regulated by the 
standardization of testing procedures in this rulemaking. Categories 
and entities that may ultimately be regulated include:

----------------------------------------------------------------------------------------------------------------
                                                                              Examples of potentially regulated 
                                  Category                                                 entities             
----------------------------------------------------------------------------------------------------------------
State and Territorial Governments and Indian Tribes........................  States, Territories, and Tribes    
                                                                              that analyze water samples on     
                                                                              behalf of public water systems    
                                                                              required to conduct such analysis;
                                                                              States, Territories, and Tribes   
                                                                              that themselves operate public    
                                                                              water systems required to conduct 
                                                                              analytic monitoring.              
Industry...................................................................  Industrial operators of public     
                                                                              water systems.                    
Municipalities.............................................................  Municipal operators of public water
                                                                              systems.                          
----------------------------------------------------------------------------------------------------------------

    This table is not intended to be exhaustive, but rather provides a 
guide for readers regarding entities likely to be regulated by this 
action. This table lists the types of entities that EPA is now aware 
could potentially be regulated by this action. Other types of entities 
not listed in the table could also be regulated. To determine whether 
your organization is or would be regulated by this action, you should 
carefully examine the applicability language at 40 CFR 141.2 
(definition of public water system). If you have questions regarding 
the applicability of this action to a particular entity, consult the 
person listed in the preceding FOR FURTHER INFORMATION CONTACT section.

[[Page 41135]]

Regional Contacts

EPA Regional Offices

I

JFK Federal Bldg., One Congress Street, 11th Floor, Boston, MA 
02203. Phone: 617-565-3602, Linda Murphy

II

290 Broadway, 24th Floor, New York, NY 10007. Phone: 212-637-3880, 
Walter Andrews

III

841 Chestnut Building, Philadelphia, PA 19107. Phone: 215-597-6511, 
Victoria Binetti

IV

345 Courtland Street, NE, Atlanta, GA 30365. Phone: 404-347-2207, 
Stallings Howell

V

77 West Jackson Boulevard, Chicago, IL 60604. Phone: 312-886-6206, 
Charlene Denys

VI

1445 Ross Avenue, Suite 1200, Dallas, TX 75202. Phone: 214-655-7150, 
Larry Wright

VII

726 Minnesota Avenue, Kansas City, KS 66101. Phone: 913-551-7682, 
Robert Morby

VIII

One Denver Place, 999 18th Street, Suite 500, Denver, CO 80202. 
Phone: 303-293-1652, Jack Rychecky

IX

75 Hawthorne Street, San Francisco, CA 94105. Phone: 415-744-1817, 
William Thurston

X

1200 Sixth Avenue, Seattle, WA 98101. Phone: 206-553-1893, Larry 
Worley

Electronic Comment Submission

    Electronic comments should be addressed to the Internet address: 
[email protected]. Electronic comments must be submitted as an 
ASCII file and avoid use of special characters and any form of 
encryption. Electronic comments must be identified by the docket number 
W-97-05. Comments and data will also be accepted on disks in 
WordPerfect in 5.1 or 6.1 format or ASCII file format. Electronic 
comments on this notice may be filed online at many Federal Depository 
Libraries. Electronic comments will be transferred into a paper version 
for the official record. EPA will attempt to clarify electronic 
comments if there is an apparent error in transmission. Comments 
provided electronically will be considered timely if they are submitted 
electronically by 11:59 p.m. (Eastern time) on September 29, 1998.

Information on Internet Access

    This Federal Register document has been placed on the Internet for 
public review and downloading at the following location: http://
www.epa.gov/fedrgstr.

Availability and Sources for Methods

    Copies of final methods published by EPA are available for a 
nominal cost through the National Technical Information Service (NTIS), 
U.S. Department of Commerce, 5285 Port Royal Road, Springfield, VA 
22161. NTIS also may be reached at 800-553-6847. Copies of draft EPA 
methods may be obtained from USEPA, National Exposure Research 
Laboratory (NERL)-Cincinnati, 26 West Martin Luther King Drive, 
Cincinnati, OH 45268. FAX request for copies of draft EPA methods may 
be sent to NERL-Cincinnati at 513-569-7757. All other methods must be 
obtained from the publisher. Publishers (with addresses) for all 
approved methods are cited at 40 CFR part 141 and in the References 
section of today's rule.

Table of Contents

I. Statutory Authority
II. Regulatory Background
III. Explanation of Today's Action
    A. New Membrane Filter Medium for the Simultaneous Detection of 
Total Coliform and E. coli
    B. Pesticide Methods
    C. New Information on Previously Approved Colisure Test
    D. Amendments and Clarifications
    E. Performance-based Measurement Systems
IV. Regulation Assessment Requirements
V. References

I. Statutory Authority

    The Safe Drinking Water Act (SDWA), as amended in 1996, requires 
EPA to promulgate national primary drinking water regulations (NPDWRs) 
which specify maximum contaminant levels (MCLs) or treatment techniques 
for drinking water contaminants SDWA section 1412, 42 U.S.C. 300g-1. 
NPDWRs apply to public water systems pursuant to SDWA section 1401, 42 
U.S.C. 300f(1)(A). According to SDWA section 1401(1)(D) of the Act, 
NPDWRs include ``criteria and procedures to assure a supply of drinking 
water which dependably complies with such maximum contaminant levels; 
including quality control and testing procedure. * * *'' see 42 U.S.C. 
300f(1)(D). In addition, SDWA section 1445(a) of the Act authorizes the 
Administrator to establish regulations for monitoring to assist in 
determining whether persons are acting in compliance with the 
requirements of the SDWA see 42 U.S.C. 300j-4. EPA's promulgation of 
analytical methods is authorized under these sections of the SDWA as 
well as the general rulemaking authority in SDWA section 1450(a), 42 
U.S.C. 300j-9(a).

II. Regulatory Background

    EPA has promulgated analytical methods for all currently regulated 
drinking water contaminants for which MCLs or monitoring requirements 
have been promulgated. In most cases, the Agency has approved use of 
more than one analytical method for measurement of a contaminant, and 
laboratories may use any approved method for determining compliance 
with an MCL or monitoring requirement. After any regulation is 
published, EPA may amend the regulations to approve additional methods, 
or modifications to approved methods, or withdraw methods that become 
obsolete or amend other requirements (such as certification 
requirements) for the use of approved methods. EPA takes these actions 
as quickly as possible after new or revised methods are published.

III. Explanation of Today's Action

    This proposal invites public comment on a new medium for 
microbiological testing, on three revised chemical analytical methods 
for acid herbicides and diquat, on withdrawal of an obsolete EPA method 
for diquat and on methods-related changes to the regulations as 
follows. EPA is proposing to approve the use of a new membrane filter 
medium, 4-methylumbelliferyl-beta-D-galactopyranoside indoxyl-beta-D 
gluconoride (MI) agar, for the determination of total coliforms and E. 
coli, and to amend the regulations to codify the current recommendation 
to ship microbiological samples below 10  deg.C. EPA is proposing a 
revised method (EPA Method 515.3) for acid herbicides, but would not 
withdraw approval of EPA Methods 515.1 or 515.2 for determination of 
acid herbicides because these methods are not obsolete. EPA is also 
proposing American Society for Testing and Materials (ASTM) method 
D5317-93 for acid herbicides provided quality control limits specified 
in EPA Method 515.1 are met. EPA is proposing to withdraw approval of 
EPA Method 549.1 for measurement of diquat and to replace it with an 
improved version, EPA Method 549.2. Withdrawal of EPA Method 549.1 
would be effective 18 months after promulgation of a final rule that 
would approve EPA Method 549.2 for diquat. EPA is proposing to amend 
the certification regulations to clarify that analysis for certain 
additional

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contaminants does not require certification. Finally, the proposal 
would also require a laboratory to successfully analyze a PE sample for 
each method for which the laboratory seeks certification rather than 
one PE sample per analyte.

A. New Membrane Filter Medium for the Simultaneous Detection of Total 
Coliform and E. coli

    EPA is proposing the approval of a new membrane filter medium known 
as MI Agar for the simultaneous detection of total coliforms and E. 
coli in drinking water samples and the enumeration of total coliforms 
in raw water samples. In a procedure developed by EPA, a water sample 
is passed through a membrane filter and the filter is placed on an MI 
Agar plate (Brenner 1993). The medium is incubated at 35  deg.C for 16-
24 hours and examined either for fluorescence of total coliforms under 
longwave (366 nm) ultraviolet light or for the blue color under ambient 
light that is characteristic of E. coli.
    The MI Agar procedure is based on the ability of total coliforms to 
produce the enzyme beta-galactosidase which hydrolyzes the 4-
methylumbelliferyl-beta-D-galactopyranoside in the medium to form a 
product which fluoresces. The procedure is also based on the ability of 
E. coli to produce the enzyme beta-glucuronidase which hydrolyzes 
indoxyl-beta-D-glucuronide to form a blue color.
    In a comparison study between the membrane filter test using MI 
Agar and already approved reference media (mEndo agar, Nutrient 
Agar+MUG), the MI Agar performed equal to or better than the reference 
media and non-coliform background counts were significantly lower for 
MI Agar (Brenner 1993, 1996a,b). For total coliforms the false-positive 
rate was 4.9% and the false-negative rate was less than 8.8%. The 
false-positive and false-negative rates for E. coli were both 4.3% 
(Brenner 1993). Based upon these results, EPA believes that the 
membrane filter method using MI Agar is satisfactory as a compliance 
method for total coliforms and E. coli.

B. Pesticide Methods

Draft EPA Method 515.3, Acid Herbicides
    EPA is proposing a draft of EPA Method 515.3 (EPA 1996) as a 
modification of, but not replacement for, EPA Method 515.1 (EPA 1995). 
Both methods require hydrolysis and derivatization of the herbicides, 
and rely on use of liquid-liquid extraction (LLE) and gas 
chromatographic analysis with an electron capture detector. EPA Method 
515.3 uses a different reagent to derivatize the acid herbicides, 
smaller volumes of drinking water sample and less extraction solvent. 
EPA Method 515.2 (EPA 1995) for acid herbicides, which uses solid phase 
extraction (SPE) will also continue to be approved because many 
laboratories prefer SPE as a solvent-saving alternative to the LLE step 
in EPA Methods 515.1 and 515.3.
    EPA has been asked to offer alternatives to diazomethane as the 
derivatizing reagent because it can form explosive products if it is 
not handled carefully and in small amounts. EPA's current alternative 
reagent, trimethylsilyldiazomethane (TMSD), produces acceptable results 
and is being retained as an option in EPA Method 515.1. Use of TMSD 
however, can produce unwanted interferences in the chromatography. EPA 
is developing Method 515.3 to find an effective alternative reagent 
that produces fewer impurities.
    EPA is proposing a draft of EPA Method 515.3 for comment while 
development work is continuing. EPA realizes the draft method contains 
method detection limits (MDLs) for some analytes that exceed detection 
limits specified at 40 CFR 141.24(h)(18). These detection limits 
specify a minimum sensitivity required to demonstrate that a 
contaminant has not been detected in a compliance sample. Systems with 
nondetects are often eligible for a reduced frequency for repeat 
monitoring. Data in tables 2 and 3 of draft EPA Method 515.3 list MDLs 
for two types of derivatization. Table 2 is for derivatization with 
diazomethane, and MDLs for four (2,4-D, dinoseb, pentachlorophenol and 
picloram) of the six regulated acid herbicides exceed detection limits 
specified in the regulations. Table 3 is for derivatization with 
tetrabutylammonium hydroxide and methyl iodide, and MDLs for three 
(2,4-D, dinoseb and picloram) acid herbicides exceed the regulatory 
limits. However, because EPA Method 515.3 has sufficient sensitivity 
and reproducibility to determine that any regulated acid herbicide is 
reliably and consistently below the MCL, this method would be used to 
screen for acid herbicides in follow-up samples that are required when 
a regulated herbicide has been detected in prior monitoring by a more 
sensitive measurement. Also, in routine use, some laboratories may be 
able to improve the sensitivity of EPA Method 515.3 and achieve the 
required detection limits for 2,4-D, dinoseb, pentachlorophenol and 
picloram.
    EPA proposes to approve draft EPA Method 515.3 for compliance 
determinations of all six regulated acid herbicides (2,4-D, 2,4,5-TP, 
dalapon, dinoseb, pentachlorophenol and picloram) and the unregulated 
acid herbicide, dicamba. Final approval for compliance monitoring would 
be contingent upon public comment and EPA's evaluation of the final 
development work, which would include second laboratory validation of 
the method.
ASTM Method D5317-93, Acid Herbicides
    ASTM Method D5317-93 (ASTM 1996) uses procedures (sodium hydroxide 
hydrolysis, diazomethane derivatization, liquid-liquid extraction and 
gas chromatography with electron capture detection) that are equivalent 
to those used in EPA Method 515.1. EPA is proposing to approve this 
1993 version of ASTM D5317 for determination of five acid herbicides in 
drinking water samples. The approval would be contingent upon 
superseding the variable control limit for the laboratory fortified 
blank (LFB), specified in section 6g of D5317-93, with the fixed upper 
control limit of 30% specified in sections 9.3.2 and 9.7.2 
of EPA Method 515.1 (Rev. 4.1). The variable control limit criterion 
for the LFB specified in D5317-93 is equivalent to the variable limit 
specified in section 10.7.2 of the 1989 version, Rev. 4.0, of EPA 
Method 515.1. EPA published Rev. 4.1 of EPA Method 515.1 to specify a 
fixed upper limit of  30% for the LFB in 1995, which was 
after the last update of ASTM D5317-93.
    The detection limits listed for pentachlorophenol (PCP) and 2,4-D 
in Table 1 of the ASTM method exceed the limits specified at 40 CFR 
141.24(h)(18). However, the method has sufficient sensitivity and 
reproducibility to determine that either herbicide is reliably and 
consistently below the MCL. Thus, D5317-93 could be useful to screen 
for PCP or 2,4-D in follow-up compliance samples that might be required 
when detection of the target acid herbicide has been established by 
prior monitoring. Also, in routine use, some laboratories may be able 
to improve the sensitivity of D5317-93 so that it would be suitable for 
lower level compliance monitoring of PCP or 2,4-D. Although D5317-93 
should be applicable to compliance determinations of dalapon and 
dinoseb, the method does not contain performance data for these two 
analytes. Therefore, EPA proposes to approve D5317-93 for compliance 
determinations of four regulated acid herbicides: PCP, picloram, 2,4-D 
and 2,4,5-TP, and the unregulated acid

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herbicide, dicamba, but not for determinations of dalapon or dinoseb. 
EPA also proposes to add a footnote to the tables of approved methods 
to require that the  30% control limits for the LFB 
specified in EPA Method 515.1 (Rev. 4.1) supersede the variable limits 
specified in D5317-93.
Draft Method 549.2, Diquat
    EPA is proposing a draft version of EPA Method 549.2 (EPA 1997a) as 
a revision of EPA Method 549.1. Both versions use ion exchange with a 
specially conditioned C8 cartridge or disk to remove diquat 
from the water sample. In the revised version, EPA Method 549.2, the 
sample pH is not adjusted to 10.5 before extraction because EPA has 
determined that this adjustment does not improve the extraction of 
diquat. Also, at pH 10.5, a precipitate is formed in several hard water 
samples. The precipitate causes very long delays in passing the sample 
through the solid phase sorbent, which result in unacceptably low 
recoveries of diquat. Changes resulting in EPA Method 549.2 are 
supported by data contained in the method that demonstrate acceptable 
extraction efficiency of method analytes at pH 7. No precipitation 
occurred in the pH range of 7 to 9 in artificial matrices simulating 
extremely hard water.
    Data included in the EPA Method 549.2 shows that recovery of diquat 
is more variable and lower than with normal phase liquid-solid 
extraction (LSE) of organic compounds (cf. Method 525.2). Matrix 
effects are expected to be more of a problem with ion exchange because 
it is affected by the ionic strength and ionic composition of the 
drinking water sample, both of which can vary greatly with time and 
with the type of source.
    In addition to matrix effects, EPA has observed significant 
variability in diquat recovery between brands of media. The variability 
appears to be greater with cartridge than with disk media. EPA seeks 
comment on what additional QC steps could be added to the method to 
detect and correct this problem. For example, EPA could increase the 
frequency of required matrix spikes from the current rate of 10%. EPA 
also seeks advice on ways to detect and correct for performance 
differences between brands (or within lots) of extraction media.
    EPA believes EPA Method 549.2 is superior to EPA Method 549.1 
because it solves the precipitation problem. The diquat recovery 
problem described above occurs with either version of the method. 
Therefore, the recovery rate is equivalent for both methods. Final 
approval of EPA Method 549.2 and withdrawal of EPA Method 549.1 would 
be contingent upon public comment and EPA's evaluation of the final 
development work. This work would include second laboratory validation 
with a variety of matrices spiked with diquat.
Other Methods for Acid Herbicides and Diquat
    Under section 12(d) of the National Technology Transfer and 
Advancement Act, the Agency is directed to use voluntary consensus 
standards in its regulatory activities unless to do so would be 
inconsistent with applicable law or otherwise impractical. Voluntary 
consensus standards are technical standards which are developed or 
adopted by voluntary consensus standard bodies. EPA searched for 
acceptable voluntary consensus standards to propose with the methods 
EPA is proposing in this rule for diquat (EPA Method 549.2) and for 
acid herbicides (EPA Method 515.3). There are no methods for diquat 
that are published by ASTM or the Standard Methods for Examination of 
Water and Wastewater (Standard Methods or SM). These organizations 
have, however, published a method for acid herbicides (ASTM D 5317-93 
and SM 6640B, respectively) that EPA evaluated for today's proposal.
    As discussed above, EPA is proposing to approve ASTM D 5317-93 for 
five acid herbicides: 2,4-D, 2,4,5-TP, dalapon, dicamba, 
pentachlorophenol and picloram. EPA also evaluated SM 6640B (APHA 
1995), which Standard Methods developed to be similar to EPA Method 
515.1 (Rev. 4.0). SM 6640B measures all of the unregulated and 
regulated acid herbicides with MDLs that meet the detection limits 
specified at 40 CFR 141.24(h)(18). EPA does not propose SM 6640B in 
today's rule because SM 6640B uses sample preparation and quality 
control procedures that are not similar enough to be judged equivalent 
to procedures specified in EPA Method 515.1, Rev. 4.1. In the next 
paragraphs, EPA provides reasons why, if used as written, use of SM 
6640B could lead to under reporting of acid herbicide contamination in 
compliance samples.
    The sample preparation instructions in sections 2, 4 b and c of SM 
6640B refer to the hydrolysis step as ``an optional procedure for 
simplified alkaline solvent wash of difficult matrices''. Hydrolysis is 
not optional nor is its primary function to clean-up ``difficult 
matrices'' in the EPA method. As explained in section 2.1 of EPA Method 
515.1, the regulated herbicides are ``applied as a variety of salts and 
esters''. Thus ``it is vital to hydrolyze them to the parent acid prior 
to extraction'' and derivatization. EPA has previously reinforced the 
necessity of hydrolysis with a footnote in the tables of approved 
methods at 40 CFR 141.24(e) and 141.40(n)(11) to state that hydrolysis 
is mandatory, not optional. EPA believes, that as written, analysts 
using SM 6640B might believe the ``alkaline solvent wash,'' which is 
not a wash but a critical chemical conversion step, is not needed in 
relatively clean matrices, such as drinking water.
    Two significant problems with the procedures specified in SM 6640B 
for use of an internal standard are the possibility of interferences 
and losses due to addition of the standard at the wrong time. To 
calibrate the instrument, EPA Method 515.1 requires use of an internal 
standard. EPA selected 4,4'-dibromooctofluorobiphenyl (DBOB) because 
DBOB is not likely to be a sample contaminant. Instructions in 3c of 
the quality control section of SM 6640 B specify use of 1,2,3-
trichloropropane (TCP), which may be a sample contaminant because TCP 
is both a solvent used as an industrial degreaser and a potential 
chemical by-product of drinking water disinfection. Addition of TCP 
rather than DBOB to sample extracts may lead to erroneous calibration 
because of interference from TCP in waters contaminated with TCP runoff 
or discharge, or with TCP synthesized during disinfection of the 
drinking water supply. Sections 4b and 6f of SM 6640B allow the analyst 
the discretion not to use an internal standard (6f) or to add it prior 
to, rather than after, derivatization of the sample (4b). EPA Method 
515.1 does not allow use of an internal standard to be optional and it 
must be added after derivatization of the sample extract so as not to 
incur losses from incomplete derivatization of the internal standard.
    To propose the current version of SM 6640B for compliance 
monitoring of acid herbicides would require EPA to annotate the listing 
in the CFR with several footnotes to supersede sample preparation and 
quality control procedures that are specified in SM 6640B. Because 
footnotes in the CFR have the potential to become separated from the 
written method used by the analyst, EPA keeps these footnotes to a 
minimum. Rather than propose SM 6640B in today's rule, EPA prefers to 
work directly with the Standard Methods committee to revise SM 6640 B 
for publication in the 21st edition of Standard Methods or in the 
supplement to the 20th edition. EPA solicits compelling reasons why it 
would be

[[Page 41138]]

beneficial to approve the current version of SM 6640B for compliance 
monitoring.

C. New Information on Previously Approved Colisure Test

    The Millipore Corporation has submitted data to EPA indicating that 
the Colisure Test, which EPA previously approved for the determination 
of total coliform and E. coli under the Total Coliform Rule, can be 
read after a 24-hour incubation period. Currently, the regulation at 40 
CFR 141.21(f)(3) (footnote 7 to the Table) specifies a minimum 
incubation time of 28 hours. EPA is now in the process of evaluating 
the data. The Agency has placed a copy of Millipore's submission in the 
Water Docket and is requesting public comment on the minimum incubation 
time for the Colisure Test.

D. Amendments and Clarifications

    The Agency is proposing to amend and clarify laboratory 
certification requirements and to amend the regulations to codify as a 
requirement the current recommendation to ship microbiological samples 
below 10  deg.C.
Require Chilling of Microbiological Samples During Storage and Transit
    EPA is proposing to require that all source water samples collected 
for the analysis of total coliforms or fecal coliforms under the 
Surface Water Treatment Rule (SWTR), or any distribution system sample 
collected for the analysis of heterotrophic bacteria, be held at a 
temperature below 10  deg.C during storage and transit. Currently, in a 
footnote to the table at 40 CFR 141.74(a)(1), EPA encourages, but does 
not require, systems to meet this provision. The Agency would make the 
holding temperature limit mandatory because it believes that microbial 
densities in a water sample may change dramatically at higher 
temperatures over a short period of time (hours) and would thus no 
longer mirror the microbial densities in the water from which they 
originated. The proposed change in holding temperature would render the 
EPA methods consistent with SM 9060B (APHA 1995) which requires that 
water samples for microbiological examination be held at temperatures 
below 10  deg.C. The proposal would not change the holding time and 
temperature provisions for total coliform, fecal coliform, or E. coli 
samples collected in the distribution system to meet the requirements 
of the Total Coliform Rule (TCR) at 40 CFR 141.21(f). Analysis under 
the TCR require determination of presence and absence of microorganisms 
and not their densities, and are therefore less sensitive to storage 
and transit temperature changes.
Updating CFR Section Citations
    The regulations at 40 CFR 141.28(a) applicable compliance 
determinations by certified laboratories currently read as follows:

    For the purpose of determining compliance with Secs. 141.21 
through 141.27, 141.41 and 141.42, samples may be considered only if 
they have been analyzed by a laboratory certified by the State 
except that measurements for turbidity, free chlorine residual, 
temperature and pH may be performed by any person acceptable to the 
State.''

EPA proposes to change the term ``free chlorine residual'' in this 
section to ``disinfectant residual'' for accuracy. The term ``free 
chlorine'' is confusing because it begs the question whether a 
laboratory must be certified to conduct analysis for disinfectant 
residuals other than free chlorine residuals. The proposed change would 
specify the more correct and broader term, disinfectant residual. 
Current federal regulations do not require certification for measuring 
any of the disinfectant residuals. States already approve the 
measurement of disinfectant residuals by any person acceptable to the 
State.
    EPA also proposes to amend Sec. 141.28(a) to add trihalomethane, 
unregulated contaminant, filtration and disinfectant, and lead 
monitoring sections (Secs. 141.30, 141.40, 141.74, 141.89, 
respectively) and to remove obsolete section references to sodium and 
corrosivity monitoring (Secs. 141.41 and 141.42). This change would 
impose no new burden because certification requirements for these 
parameters are currently specified elsewhere in federal regulations. 
The change merely clarifies that 40 CFR 141.28(a) also applies to these 
parameters.
    EPA proposes to amend 40 CFR 141.28(a) and 141.89(a)(1) to address 
confusion about whether a laboratory must be certified to conduct 
monitoring for certain additional contaminants. Currently, 40 CFR 
141.89(a)(1) requires certification to conduct analyses for lead, 
copper, alkalinity, calcium, conductivity, orthophosphate and silica. 
However, the regulations specify acceptance criteria only for the 
analysis of samples for lead and copper and not for alkalinity, 
calcium, conductivity, orthophosphate and silica. Acceptance criteria 
for these latter five contaminants were omitted because EPA intended 
for the certification exception provisions of 40 CFR 141.28(a) to apply 
to these contaminants the same way the exceptions apply for pH, 
temperature, turbidity and disinfectant residuals. The certification 
exceptions at 40 CFR 141.28 (a) state that certain analyses may be 
conducted by any person acceptable to the State. The regulations at 40 
CFR 141.28 (a) and 141.89(a)(1) would be amended to clarify EPA's 
intent that analyses for alkalinity, calcium, conductivity, 
disinfectant residual, orthophosphate, pH, silica, temperature and 
turbidity may be performed by any person acceptable to the State. 
Section 40 CFR 141.89 would no longer require certification for the 
measurement of these contaminants.
Requirement To Report Method Used To Analyze PE Samples
    EPA proposes to amend the NPDWRs at Secs. 141.23(k), 141.24(f) and 
(h) and 141.89(a) in order to provide greater assurance that public 
water systems dependably comply with MCLs. Those regulations describe 
the Performance Evaluation (PE) sample analysis requirements associated 
with compliance monitoring for certain contaminants regulated under the 
SDWA. The regulations provide that analysis for the drinking water 
contaminants regulated under those sections must be conducted by a 
laboratory that has received certification by EPA or the State. These 
regulations further provide that, in order for a laboratory to receive 
certification to conduct analyses for the regulated contaminants, the 
laboratory must analyze PE samples for the regulated contaminants. PE 
sample testing is intended to ensure that the laboratory accurately 
measures the contaminant of concern, i.e., is proficient in the 
analysis for such contaminants.
    To ensure that public water systems dependably comply with MCLs, 
EPA proposes to amend the PE sample requirement to specify that a 
laboratory needs to be certified not only for measurement of specific 
contaminants, but also that such certification must specify the 
method(s) used by that laboratory for evaluation of such 
contaminant(s). The Agency's primary concern is that laboratories be 
certified for the proficiency on the methods they actually use for 
analysis for water samples used in compliance monitoring. In the 
recently published fourth edition of the Manual for the Certification 
of Drinking Water Laboratories (EPA 1997b), EPA's laboratory 
certification guidance, the Agency recommended that EPA and State 
certifying agencies require a laboratory to successfully analyze a PE 
sample for each method for which the laboratory seeks certification 
rather than one PE sample per analyte. Today's proposal would codify 
that

[[Page 41139]]

recommendation. EPA believes this is a reasonable change because 
laboratories always have had to report to the PE sample provider what 
method was used to analyze the PE sample. Many, if not most, State 
laboratory certification officers currently require this information.
    As currently written, the PE sample requirements at 
Secs. 141.23(k), 141.24(f) and (h) and 141.89(a) allow certification 
for any method approved for measurement of the target analyte provided 
that the laboratory successfully analyzed the PE sample with any one of 
the approved methods. Under today's proposal, EPA would clarify the 
regulations to carry out the original intent of requiring a 
certification certificate to describe both the analyte and approved 
method covered by the certificate. The proposed change would, for 
example, require successful analysis of a PE sample with both EPA 
Method 524.2 and 502.2 to obtain certification for VOCs if the 
laboratory elects to use both mass spectrometer and electrolytic 
conductivity/photo ionization technologies, respectively, to measure 
VOCs. Under today's proposal, no laboratory would be required to use 
methods that it would not otherwise use. The requirement would merely 
require proficiency in using the methods the laboratory has chosen to 
use. This amendment would only affect laboratories that both (1) choose 
to be certified for the same analyte with more than one method and (2) 
are not already required by their certification authority to be 
certified by method and by analyte. EPA is interested in any comments 
that provide compelling reasons to show that this modification to the 
PE sample requirements would be unnecessary or unreasonable. EPA is 
also seeking comments on this requirement in regards to the national 
standards for accreditation of environmental laboratories which 
National Environmental Laboratory Accreditation Conference (NELAC) is 
developing, and the Agency's implementation of a Performance-Based 
Measurement System in the future. NELAC is sponsored by EPA as a 
voluntary association of state and federal officials with the purpose 
of developing national performance standards for environmental 
laboratories. NELAC standards are available on the Internet at http://
www.epa.gov/ttn/nelac/.

E. Performance-Based Measurement System

    On October 6, 1997, EPA published a Notice of the Agency's intent 
to implement a Performance-Based Measurement System (PBMS) in all of 
its programs to the extent feasible (62 FR 52098). The Agency is 
currently determining the specific steps necessary to implement PBMS in 
its programs and preparing an implementation plan. Final decisions have 
not yet been made concerning the implementation of PBMS in water 
programs. However, EPA is currently evaluating what relevant 
performance characteristics should be specified for monitoring methods 
used in the water programs under a PBMS approach to ensure adequate 
data quality. EPA would then specify performance requirements in its 
regulations to ensure that any method used for determination of a 
regulated analyte is at least equivalent to the performance achieved by 
other currently approved methods. Our expectation is that EPA will 
publish its PBMS implementation strategy for water programs in the 
Federal Register by the end of calendar year 1998.
    Once EPA has made its final determinations regarding implementation 
of PBMS in programs under the Safe Drinking Water Act, EPA would 
incorporate specific provisions of PBMS into its regulations, which may 
include specification of the performance characteristics for 
measurement of regulated contaminants in the drinking water program 
regulations.

IV. Regulation Assessment Requirements

A. Executive Order 12866

    Under Executive Order 12866 (58 FR 51735; October 4, 1993), the 
Agency must determine whether the regulatory action is ``significant'' 
and therefore subject to OMB review and the requirements of the 
Executive Order. The Order defines ``significant regulatory action'' as 
one that is likely to result in a rule that may:
    (1) Have an annual effect on the economy of $100 million or more, 
or adversely affect in a material way the economy, a sector of the 
economy, productivity, competition, jobs, the environment, public 
health or safety, or State, local, or tribal governments or 
communities;
    (2) Create a serious inconsistency or otherwise interfere with an 
action taken or planned by another agency;
    (3) Materially alter the budgetary impact of entitlement, grants, 
user fees, or loan programs or the rights and obligations of recipients 
thereof; or
    (4) Raise novel legal or policy issues arising out of legal 
mandates, the President's priorities, or the principles set forth in 
the Executive Order.
    It has been determined that this rule is not a ``significant 
regulatory action'' under the terms of Executive Order 12866 and is 
therefore not subject to OMB review.

B. Regulatory Flexibility Act

    Under the Regulatory Flexibility Act (RFA), EPA generally is 
required to conduct a regulatory flexibility analysis describing the 
impact of the regulatory action on small entities as part of 
rulemaking. However, under section 605(b) of the RFA, if EPA certifies 
that the rule will not have a significant economic impact on a 
substantial number of small entities, EPA is not required to prepare a 
regulatory flexibility analysis. Pursuant to section 605(b) of the 
Regulatory Flexibility Act, 5 U.S.C. 605(b), the Administrator 
certifies that this rule will not have a significant economic impact on 
a substantial number of small entities (for purposes of EPA's analysis, 
the Agency defines small entities as 10,000 or fewer customers or small 
laboratories with sales revenue below $6 million annually).
    This rule proposes to approve revised methods for compliance 
determination of selected chemical and microbial contaminants. Previous 
versions of all methods for these contaminants except for diquat will 
continue to be approved. EPA is proposing to withdraw approval of its 
current method for diquat. EPA has determined that requiring pH 
adjustment prior extraction is not necessary. Because the proposed 
diquat method is similar in all other aspects to the currently approved 
method, withdrawal of this method and adoption of the new method will 
not have any economic burden on public water systems or the analytical 
laboratories performing analyses on behalf of these systems whether 
small entities or small businesses.
    The proposed amendment would also require that laboratories be 
certified for proficiency in the analytical method they actually use. 
Thus, in the case of laboratories that choose to be certified for an 
analyte using more than one approved method, the regulation would 
require such laboratories to analyze a PE sample for each method for 
which certification is requested. Small laboratories are not expected 
to consider this option. Currently most laboratories elect to be 
certified for only one method and there is no reason to believe this 
situation will change. Even if some small laboratories elected to seek 
certification for more than one method for some analytes, EPA has 
concluded that the number doing so would be few and the consequent 
economic impact on

[[Page 41140]]

laboratories that are small businesses would not be significant.
    The proposal to hold source water samples for microbiological 
analysis below 10  deg.C during transit/storage is also not expected to 
cause any significant increase in monitoring cost for big or small 
water systems. The Agency anticipates that only about 2,000 surface 
water systems which do not currently filter water (approx. 1% of all 
systems) will be affected by the cooling requirement for total coliform 
and fecal coliform samples. All surface water systems (approx. 9% of 
all systems) will be affected by the cooling requirement for 
heterotrophic plate count (HPC). However, the HPC requirement is an 
optional substitute for maintaining a detectable disinfection residual. 
The requirement to hold samples below 10  deg.C can be easily met by 
shipping samples in reusable ice packs. EPA estimates a one time cost 
of less than $5 per sample for the ice packs; over a period of time 
this represents only a slight increase in sample shipping cost under 
current requirements. Based on the above stated considerations, the 
Agency concluded that this proposal, if promulgated, will not have a 
significant economic impact on a substantial number of small entities.

C. Unfunded Mandates Reform Act

    Title II of the Unfunded Mandates Reform Act of 1995 (UMRA), Pub.L. 
104-4, establishes requirements for Federal agencies to assess the 
effects of their regulatory actions on State, local, and tribal 
governments and the private sector. Under section 202 of the UMRA, EPA 
generally must prepare a written statement, including a cost-benefit 
analysis, for proposed and final rules with ``Federal mandates'' that 
may result in expenditures to State, local, and tribal governments, in 
the aggregate, or to the private sector, of $100 million or more in any 
one year. Before promulgating an EPA rule for which a written statement 
is needed, section 205 of the UMRA generally requires EPA to identify 
and consider a reasonable number of regulatory alternatives and adopt 
the least costly, most cost-effective or least burdensome alternative 
that achieves the objectives of the rule. The provisions of section 205 
do not apply when they are inconsistent with applicable law. Moreover, 
section 205 allows EPA to adopt an alternative other than the least 
costly, most cost-effective or least burdensome alternative if the 
Administrator publishes with the final rule an explanation why that 
alternative was not adopted. Before EPA establishes any regulatory 
requirements that may significantly or uniquely affect small 
governments, including tribal governments, it must have developed under 
section 203 of the UMRA a small government agency plan. The plan must 
provide for notifying potentially affected small governments, enabling 
officials of affected small governments to have meaningful and timely 
input in the development of EPA regulatory proposals with significant 
Federal intergovernmental mandates, and informing, educating, and 
advising small governments on compliance with the regulatory 
requirements.
    EPA has determined that this rule does not contain any Federal 
mandate that may result in expenditures of $100 million or more for 
State, local, and tribal governments, in the aggregate, or the private 
sector in any one year. Therefore, today's proposed rule is not subject 
to the requirements of section 202 and 205 of the UMRA.
    Today's rule proposes use of additional analytical methods by 
public water systems and laboratories conducting analysis for 
contaminants in drinking water. Therefore, the proposal would provide 
regulatory relief in the form of increased operational flexibility to 
laboratory analysts. Earlier versions of all methods approved in this 
proposed rule (except for the diquat method) would continue to be 
approved. The withdrawal of the earlier version of the diquat method 
would not adversely affect analytical laboratories because the new 
version is simpler and easier to use. The proposed amendment requiring 
that laboratories be certified based on the proficiency on the method 
they actually use, would impose a minor requirement for laboratories 
that choose to be certified for an analyte by more than one method. 
Currently most laboratories elect to be certified by one method and 
there is no reason to believe laboratories would be compelled to incur 
the cost of an additional PE sample in the future. The requirement to 
hold source water samples below 10 deg.C during transit/storage would 
affect only a small fraction (1-9%) of the water utilities and the 
effect on monitoring cost would be very minor, and attributable to a 
slight increase in sample shipping cost.
    Based on the information presented above, EPA has determined that 
this rule contains no regulatory requirements that might significantly 
or uniquely affect small governments. Therefore, today's proposed rule 
is not subject to section 203 of UMRA.

D. Paperwork Reduction Act

    In accordance with the Paperwork Reduction Act of 1980, 44 U.S.C. 
3501 et seq., EPA must submit an information collection request 
covering information collection requirements in a rule to the Office of 
Management and Budget (OMB) for review and approval. This rule contains 
no information collection requirements. Therefore, preparation of an 
information collection request to accompany this rule is unnecessary.

E. Science Advisory Board and National Drinking Water Advisory Council, 
and Secretary of Health and Human Services

    In accordance with section 1412(d) and (e) of the SDWA, the Agency 
submitted this proposal to the Science Advisory Board, the National 
Drinking Water Advisory Council, and the Secretary of Health and Human 
Services for their review. They had no comments.

F. National Technology Transfer and Advancement Act

    Under section 12(d) of the National Technology Transfer and 
Advancement Act, the Agency is directed to use voluntary consensus 
standards in its regulatory activities unless to do so would be 
inconsistent with applicable law or otherwise impractical. Voluntary 
consensus standards are technical standards (e.g., material 
specifications, test methods, sampling procedures, business practices, 
etc.) that are developed or adopted by voluntary consensus standard 
bodies. Where available and potentially applicable voluntary consensus 
standards are not used by EPA, the Act requires the Agency to provide 
Congress, through the Office of Management and Budget (OMB), an 
explanation for the reasons for not using the standard.
    In preparing today's proposal, EPA searched for consensus methods 
that would be acceptable for compliance determinations under the SDWA 
for the measurement of diquat and six acid herbicides. EPA found no 
methods for diquat but found two methods (ASTM D5317-93 and SM 6640B) 
for the acid herbicides. As explained in the preamble to this proposed 
rule, EPA is proposing D5317-93 provided the QC criterion is superseded 
by a more stringent EPA criterion. EPA is not proposing SM 6640B 
because of significant shortcomings in the sample preparation and 
quality control sections of the method instructions. EPA will offer to 
work with Standard Methods to revise SM 6640B for publication in future 
editions of Standard Methods for the Examination of Water and 
Wastewater. EPA invites comments on the potential use of voluntary 
consensus standards in this rulemaking. EPA invites public comments on 
the

[[Page 41141]]

Agency's proposal as well as identification and information about other 
voluntary consensus standards, which the Agency could consider for 
determination of diquat or acid herbicides under the SDWA.

G. Executive Order 13045--Protection of Children From Environmental 
Health Risks and Safety Risks

    Today's action is not subject to Executive Order 13045 (62 FR 19885 
(April 23, 1997)), which requires agencies to identify and assess the 
environmental health and safety risks of their rules on children. 
Pursuant to the definitions in section 2-202, Executive Order 13045 
only applies to rules that are economically significant as defined 
under Executive Order 12886 and concern an environmental health or 
safety risk that may disproportionately affect children. This rule is 
not economically significant and does not concern a risk 
disproportionately affecting children.

V. References

    APHA 1995. Nineteenth edition of Standard Methods for the 
Examination of Water and Wastewater, 1995, American Public Health 
Association, 1015 Fifteenth Street NW, Washington, DC 20005.
    ASTM 1996. Annual Book of ASTM Standards, 1996, Vol. 11.02, 
American Society for Testing and Materials, 101 Barr Harbor Drive, 
West Conshohocken, PA 19428.
    Brenner 1993. Brenner, K.P, et al., ``New medium for the 
simultaneous detection of total coliform and Escherichia coli in 
water'', Appl. Environ. Microbiol. 59:3534-3544.
    Brenner 1996a. Brenner, K.P., et al., ``Comparison of the 
recoveries of Escherichia coli and total coliform from drinking 
water by the MI Agar method'', Appl. Environ. Microbiol. 62:203-208.
    Brenner 1996b. Brenner, K.P., et al., ``Interlaboratory 
evaluation of MI Agar and the U.S. Environmental Protection Agency--
approved membrane filter method for the recovery of total coliform 
and Escherichia coli from drinking water'', J. Microbiol. Methods 
27:111-119.
    EPA 1995. ``Methods for the Determination of Organic Compounds 
in Drinking Water--Supplement III,'' EPA-600/R-95-131, August 1995, 
NTIS PB95-261616.
    EPA 1996. Draft Method 515.3 is available from U.S. 
Environmental Protection Agency, National Exposure Research 
Laboratory (NERL)-Cincinnati, 26 West Martin Luther King Drive, 
Cincinnati, OH 45268.
    EPA 1997a. Draft Method 549.2 is available from U.S. 
Environmental Protection Agency, National Exposure Research 
Laboratory (NERL)-Cincinnati, 26 West Martin Luther King Drive, 
Cincinnati, OH 45268.
    EPA 1997b. Manual for the Certification of Laboratories 
Analyzing Drinking Water, Fourth Edition, Office of Water Resource 
Center (RC-4100), 401 M Street, SW, Washington, DC 20460, EPA 815-B-
97-001, March 1997.

List of Subjects in 40 CFR Part 141

    Environmental protection, Analytical methods, Chemicals, 
Incorporation by reference, Intergovernmental relations, 
Microorganisms, Monitoring, National Primary Drinking Water 
Regulations, Water supply.

    Dated: July 23, 1998.
Carol M. Browner,
Administrator.

    For the reasons set out in the preamble, part 141 of chapter I, 
title 40, Code of Federal Regulations, are proposed to be amended as 
follows:

PART 141--NATIONAL PRIMARY DRINKING WATER REGULATIONS

    1. The authority citation for part 141 continues to read as 
follows:

    Authority: 42 U.S.C. 300f, 300g-1, 300g-2, 300g-3, 300g-4, 300g-
5, 300g-6, 300j-4, 300j-9.

    2. Section 141.21 is amended by revising paragraph (f)(3) and 
adding a new (f)(6)(v) with a table to read as follows:


Sec. 141.21  Coliform sampling.

* * * * *
    (f) * * *
    (3) Public water systems must conduct total coliform analyses in 
accordance with one of the analytical methods in the following table.

----------------------------------------------------------------------------------------------------------------
                   Organism                            Methodology                      Citation \1\            
----------------------------------------------------------------------------------------------------------------
Total Coliforms \2\..........................  Total Coliform Fermentation  9221A, B                            
                                                Technique 3,4,5.                                                
                                               Total Coliform Membrane      9222A, B, C                         
                                                Filter Technique \6\.                                           
                                               Presence-Absence (P-A)       9221D                               
                                                Coliform Test 5,7.                                              
                                               ONPG-MUG Test \8\..........  9223                                
                                               Colisure Test \9\                                                
----------------------------------------------------------------------------------------------------------------
The procedures shall be done in accordance with the documents listed below. The incorporation by reference of   
  the following documents was approved by the Director of the Federal Register in accordance with 5 U.S.C.      
  552(a) and 1 CFR part 51. Copies of the documents may be obtained from the sources listed below. Information  
  regarding obtaining these documents can be obtained from the Safe Drinking Water Hotline at 800-426-4791.     
  Documents may be inspected at EPA's Drinking Water Docket, 401 M Street, SW, Washington, D.C. 20460           
  (Telephone: 202-260-3027); or at the Office of Federal Register, 800 North Capitol Street, NW, Suite 700,     
  Washington, D.C. 20408.                                                                                       
\1\ Methods 9221A, B, 9222A, B, C, 9221D and 9223 are contained in Standard Methods for the Examination of Water
  and Wastewater, 18th edition, 1992 and 19th edition, 1995, American Public Health Association, 1015 Fifteenth 
  Street NW, Washington, D.C. 20005; either edition may be used.                                                
\2\ The time from sample collection to initiation of analysis may not exceed 30 hours. Systems are encouraged   
  but not required to hold samples below 10 deg. C during transit.                                              
\3\ Lactose broth, as commercially available, may be used in lieu of lauryl tryptose broth, if the system       
  conducts at least 25 parallel tests between this medium and lauryl tryptose broth using the water normally    
  tested, and this comparison demonstrates that the false-positive rate and false-negative rate for total       
  coliform, using lactose broth, is less than 10 percent.                                                       
\4\ If inverted tubes are used to detect gas production, the media should cover these tubes at least one-half to
  two-thirds after the sample is added.                                                                         
\5\ No requirement exists to run the completed phase on 10 percent of all total coliform-positive confirmed     
  tubes.                                                                                                        
\6\ MI agar also may be used. Preparation and use of MI agar is set forth in the article, ``New medium for the  
  simultaneous detection of total coliform and Escherichia coli in water'' by Brenner, K.P., et al., 1993, Appl.
  Environ. Microbiol. 59:3534-3544.                                                                             
\7\ Six-times formulation strength may be used if the medium is filter-sterilized rather than autoclaved.       
\8\ The ONPG-MUG Test is also known as the Autoanalysis Colilert System. A source for this test is referenced at
  Sec.  141.21(f)(5)(iii).                                                                                      
\9\ The Colisure Test must be incubated for 28 hours before examining the results. If an examination of the     
  results at 28 hours is not convenient, then results may be examined at any time between 28 hours and 48 hours.
  A description of the Colisure Test may be obtained from the Millipore Corporation, Technical Services         
  Department, 80 Ashby Road, Bedford, MA 01730.                                                                 
*                    *                    *                    *                    *                    *      
               *                                                                                                

    (6) * * *
    (v) The membrane filter method with MI agar, a description of which 
is cited in a footnote to the table at paragraph (f)(3) of this 
section.
* * * * *
    3. Section 141.23(k)(3)(ii) is amended by revising the introductory 
text before the table to read as follows:

[[Page 41142]]

Sec. 141.23  Inorganic chemical sampling and analytical requirements.

* * * * *
    (k) * * *
    (3) * * *
    (ii) For each contaminant that has been included in the PE sample 
and for each method for which the laboratory desires certification 
achieve quantitative results on the analyses that are within the 
following acceptance limits:
* * * * *
    4. Section 141.24 is amended by:
    a. Revising the section heading;
    b. Adding a sentence to the end of paragraph (e);
    c. Revising, in the table in paragraphs (e), the entries for ``2,4-
D'', ``2,4,5-TP (Silvex)'', ``Dinoseb'', ``Diquat'', 
``Pentachlorophenol'' and ``Picloram''; and adding footnotes 4 and 5;
    d. Revising paragraphs (f)(17)(i)(A), (f)(17)(ii) introductory 
text; and paragraph (f)(17)(ii)(A); and
    e. Revising paragraph (h)(19)(i)(A) to read as follows:


Sec. 141.24  Organic chemicals, sampling and analytical requirements.

* * * * *
    (e) * * * EPA Draft Methods 515.3 and 549.2 are available from U.S. 
Environmental Protection Agency, National Exposure Research Laboratory 
(NERL)-Cincinnati, 26 West Martin Luther King Drive, Cincinnati, OH 
45268. ASTM Method D 5317-93 is available in the Annual Book of ASTM 
Standards, 1996, Vol. 11.02, American Society for Testing and 
Materials, 101 Barr Harbor Drive, West Conshohocken, PA 19428, or in 
any edition published after 1993.

                                                                        
           Contaminant                           Method \1\             
                                                                        
*    *    *                              *    *    *                    
2,4-D \4\ (as acid, salts and      515.2, 555, 515.1, 515.3, D5317-93   
 esters)                            \5\                                 
2,4,5-TP \4\ (Silvex)              515.2, 555, 515.1, 515.3, D5317-93   
                                    \5\                                 
*    *    *                              *    *    *                    
Dinoseb \4\                        515.2, 555, 515.1, 515.3             
Diquat                             549.2                                
*    *    *                              *    *    *                    
Pentachlorophenol                  515.2, 525.2, 555, 515.1, 515.3,     
                                    D5317-93 \5\                        
Picloram \4\                       515.2, 555, 515.1, 515.3, D5317-93   
                                    \5\                                 
*    *    *                              *    *    *                    
                                                                        
\4\ Accurate determination of the chlorinated esters requires hydrolysis
  of the sample as described in EPA Methods 515.1, 515.2, 515.3 and 555,
  and ASTM Method D5317-93.                                             
\5\ Use of ASTM D5317-93 requires that the variable control limit for   
  the laboratory fortified blank (LFB), which is specified in section 6g
  of D5317-93, be superseded by the fixed upper control limit of 30%, which is specified in sections 9.3.2 and 9.7.2 of EPA      
  Method 515.1 (Rev. 4.1).                                              

    (f) * * *
    (17) * * *
    (i) * * *
    (A) Analyze Performance Evaluation (PE) samples provided by EPA, 
the State, or by a third party (with the approval of the State or EPA) 
at least once a year by each method for which the laboratory desires 
certification.
* * * * *
    (ii) To receive certification to conduct analyses for vinyl 
chloride, the laboratory must:
    (A) Analyze Performance Evaluation (PE) samples provided by EPA, 
the State, or by a third party (with the approval of the State or EPA) 
at least once a year by each method for which the laboratory desires 
certification.
* * * * *
    (h) * * *
    (19) * * *
    (i) * * *
    (A) Analyze Performance Evaluation (PE) samples provided by EPA, 
the State, or by a third party (with the approval of the State or EPA) 
at least once a year by each method for which the laboratory desires 
certification.
* * * * *
    5. Section 141.28 is amended by revising paragraph (a) to read as 
follows:


Sec. 141.28  Certified laboratories.

    (a) For the purpose of determining compliance with Secs. 141.21 
through 141.27, 141.30, 141.40, 141.74 and 141.89, samples may be 
considered only if they have been analyzed by a laboratory certified by 
the State except that measurements for alkalinity, calcium, 
conductivity, disinfectant residual, orthophosphate, pH, silica, 
temperature and turbidity may be performed by any person acceptable to 
the State.''
* * * * *
    6. Section 141.40 is amended by revising the last sentence in 
paragraph (n)(11), entry for ``dicamba'' in paragraph (n)(11), and by 
adding two footnotes to the table in paragraph (n)(11) to read as 
follows:


Sec. 141.40  Special monitoring for inorganic and organic chemicals.

* * * * *
    (n) * * *
    (11) * * * A source for ASTM D5317-93, APHA method 6610 and for EPA 
Methods 505, 507, 508, 508.1, 515.2, 515.3, 525.2 and 531.1 is 
referenced at Sec. 141.24(e).

                                                                        
           Contaminants                            Method               
                                                                        
*    *    *                         *    *    *                         
dicamba \1\                         515.2, 555, 515.1, 515.3, D5317-93  
                                     \2\                                
*    *    *                         *    *    *                         
                                                                        
\1\ Accurate determination of the chlorinated esters requires hydrolysis
  of the sample as described in EPA Methods 515.1, 515.2, 515.3 and 555,
  and ASTM Method D5317-93.                                             
\2\ Use of ASTM D5317-93 requires that the variable control limit for   
  the laboratory fortified blank (LFB), which is specified in section 6g
  of D5317-93, be superseded by the fixed upper control limit of  30%, which is specified in sections 9.3.2 and 9.7.2 of EPA     
  Method 515.1 (Rev. 4.1).                                              

* * * * *
    7. Section 141.74 is amended by revising the table and footnotes in 
paragraph (a)(1) to read as follows:


Sec. 141.74  Analytical and monitoring requirements.

    (a) * * *
    (1) * * *

----------------------------------------------------------------------------------------------------------------
                   Organism                            Methodology                      Citation \1\            
----------------------------------------------------------------------------------------------------------------
Total Coliform \2\...........................  Total Coliform Fermentation  9221A, B, C                         
                                                Technique 3,4,5.                                                
                                               Total Coliform Membrane      9222A, B, C                         
                                                Filter Technique \6\.                                           
                                               ONPG-MUG Test \7\..........  9223                                
Fecal Coliforms \2\..........................  Fecal Coliform Procedure     9221E                               
                                                \8\.                                                            
                                               Fecal Coliform Filter        9222D                               
                                                Procedure.                                                      
Heterotrophic bacteria \2\...................  Pour Plate Method..........  9215B                               
Turbidity....................................  Nephelometric Method.......  2130B                               
                                               Nephelometric Method.......  180.1 \9\                           
                                               Great Lakes Instruments....  Method 2 \10\                       
----------------------------------------------------------------------------------------------------------------
The procedures shall be done in accordance with the documents listed below. The incorporation by reference of   
  the following documents was approved by the Director of the Federal Register in accordance with 5 U.S.C.      
  552(a) and 1 CFR part 51. Copies of the documents may be obtained from the sources listed below. Information  
  regarding obtaining these documents can be obtained from the Safe Drinking Water Hotline at 800-426-4791.     
  Documents may be inspected at EPA's Drinking Water Docket, 401 M Street, SW, Washington, D.C. 20460           
  (Telephone: 202-260-3027); or at the Office of Federal Register, 800 North Capitol Street, NW, Suite 700,     
  Washington, D.C. 20408.                                                                                       

[[Page 41143]]

                                                                                                                
\1\ Except where noted, all methods refer to Standard Methods for the Examination of Water and Wastewater, 18th 
  edition, 1992 and 19th edition, 1995, American Public Health Association, 1015 Fifteenth Street NW,           
  Washington, D.C. 20005; either edition may be used.                                                           
\2\ The time from sample collection to initiation of analysis may not exceed 8 hours. Systems must hold samples 
  below 10 deg.C during transit.                                                                                
\3\ Lactose broth, as commercially available, may be used in lieu of lauryl tryptose broth, if the system       
  conducts at least 25 parallel tests between this medium and lauryl tryptose broth using the water normally    
  tested, and this comparison demonstrates that the false-positive rate and false-negative rate for total       
  coliform, using lactose broth, is less than 10 percent.                                                       
\4\ Media should cover inverted tubes at least one-half to two-thirds after the sample is added.                
\5\ No requirement exists to run the completed phase on 10 percent of all total coliform-positive confirmed     
  tubes.                                                                                                        
\6\ MI agar also may be used. Preparation and use of MI agar is set forth in the article, ``New medium for the  
  simultaneous detection of total coliform and Escherichia coli in water'' by Brenner, K.P., et al., 1993, Appl.
  Environ. Microbiol. 59:3534-3544.                                                                             
\7\ The ONPG-MUG Test is also known as the Autoanalysis Colilert System. A source for this test is referenced at
  Sec.  141.21(f)(5)(iii).                                                                                      
\8\ A-1 Broth may be held up to three months in a tightly closed screw cap tube at 4C.                          
\9\ ``Methods for the Determination of Inorganic Substances in Environmental Samples'', EPA-600/R-93-100, August
  1993. Available at NTIS, PB94-121811.                                                                         
\10\ GLI Method 2, ``Turbidity'', November 2, 1992, Great Lakes Instruments, Inc., 8855 North 55th Street,      
  Milwaukee, Wisconsin 53223.                                                                                   
*                    *                    *                    *                    *                    *      
               *                                                                                                

    8. Section 141.89 is amended by revising paragraph (a)(1) 
introductory text and (a)(1)(i) to read as follows:


Sec. 141.89  Analytical methods.

* * * * *
    (a) * * *
    (1) Analyses for alkalinity, calcium, conductivity, 
orthophosophate, pH, silica, and temperature may be performed by any 
person acceptable to the State. Analyses under this section for lead 
and copper shall only be conducted by laboratories that have been 
certified by EPA or the State. To obtain certification to conduct 
analyses for lead and copper, laboratories must:
    (i) Analyze Performance Evaluation samples, which include lead and 
copper, provided by or acceptable to EPA or the State at least once a 
year by each method for which the laboratory desires certification; and
* * * * *

[FR Doc. 98-20281 Filed 7-30-98; 8:45 am]
BILLING CODE 6560-50-P