[Federal Register Volume 76, Number 240 (Wednesday, December 14, 2011)]
[Proposed Rules]
[Pages 77742-77747]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2011-32063]



40 CFR Part 136

[EPA-HQ-OW-2010-0192; FRL-9504-2]

Guidelines Establishing Test Procedures for the Analysis of 
Pollutants Under the Clean Water Act; Analysis and Sampling Procedures; 
Notice of Data Availability

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice of data availability.


SUMMARY: On September 23, 2010, EPA proposed to approve a number of new 
and revised test procedures (i.e., analytical methods) for measuring 
pollutants under the Clean Water Act. Today's notice announces the 
availability of new data on an analytical method for the measurement of 
oil and grease that EPA described in the earlier notice but did not 
propose to approve it for use. This notice discusses how EPA is 
considering revising its proposed regulatory requirements for this 
method. EPA is soliciting comment only on EPA's consideration of this 

DATES: Comments must be received on or before February 13, 2012.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-HQ-
2010-0192, by one of the following methods:
     http://www.regulations.gov: Follow the on-line 
instructions for submitting comments.
     Email: OW-docket@epamail.epa.gov Attention Docket ID No. 
     Mail: Water Docket, Environmental Protection Agency, 
Mailcode: 28221T, 1200 Pennsylvania Ave. NW., Washington, DC 20460.
     Hand Delivery: EPA Water Center, EPA West Building, Room 
B102, 1301 Constitution Avenue NW., Washington, DC, Attention Docket ID 
No. OW-2010-0192. Such deliveries are only accepted during the Docket's 
normal hours of operation, and special arrangements should be made for 
deliveries of boxed information.
    Instructions: Direct your comments to Docket ID No. EPA-HQ-OW-2010-
0192. EPA's policy is that all comments received will be included in 
the public docket without change and may be made available online at 
http://www.regulations.gov, including any personal information 
provided, unless the comment includes information claimed to be 
Confidential Business Information (CBI) or other information whose 
disclosure is restricted by statute.

[[Page 77743]]

Do not submit information that you consider to be CBI or otherwise 
protected through http://www.regulations.gov or email. The http://www.regulations.gov Web site is an ``anonymous access'' system, which 
means EPA will not know your identity or contact information unless you 
provide it in the body of your comment. If you send an email comment 
directly to EPA without going through http://www.regulations.gov your 
email address will be automatically captured and included as part of 
the comment that is placed in the public docket and made available on 
the Internet. If you submit an electronic comment, EPA recommends that 
you include your name and other contact information in the body of your 
comment and with any disk or CD-ROM you submit. If EPA cannot read your 
comment due to technical difficulties and cannot contact you for 
clarification, EPA may not be able to consider your comment. Electronic 
files should avoid the use of special characters, any form of 
encryption, and be free of any defects or viruses. For additional 
information about EPA's public docket visit the EPA Docket Center 
homepage at http://www.epa.gov/epahome/dockets.htm.
    Docket: All documents in the docket are listed in the http://www.regulations.gov index. Although listed in the index, some 
information is not publicly available, e.g., CBI or other information 
whose disclosure is restricted by statute. Certain other material, such 
as copyrighted material, will be publicly available only in hard copy. 
Publicly available docket materials are available either electronically 
in http://www.regulations.gov or in hard copy at the Water Docket, EPA/
DC, EPA West, Room B102, 1301 Constitution Ave. NW., Washington, DC. 
The Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday 
through Friday, excluding legal holidays. The telephone number for the 
Public Reading Room is (202) 566-1744, and the telephone number for the 
Water Docket is (202) 566-2426.

FOR FURTHER INFORMATION CONTACT: Maria Gomez-Taylor, Office of Science 
and Technology, Office of Water (4303-T), Environmental Protection 
Agency, 1200 Pennsylvania Avenue NW; Washington, DC 20460; telephone 
number: (202) 566-1005; fax number: (202) 566-1053; email address: 


I. General Information

A. Does this action apply to me?

    EPA Regions, as well as States, Territories and Tribes authorized 
to implement the National Pollutant Discharge Elimination System 
(NPDES) program, issue permits with conditions designed to ensure 
compliance with the technology-based and water quality-based 
requirements of the Clean Water Act (CWA). These permits may include 
restrictions on the quantity of pollutants that may be discharged as 
well as pollutant measurement and reporting requirements. If EPA has 
approved a test procedure for analysis of a specific pollutant, the 
NPDES permittee must use an approved test procedure (or an approved 
alternate test procedure) for the specific pollutant when measuring the 
required waste constituent. Similarly, if EPA has established sampling 
requirements, measurements taken under an NPDES permit must comply with 
these requirements. Therefore, entities with NPDES permits will 
potentially be affected by the actions in this rulemaking. Categories 
and entities that may potentially be affected by the requirements of 
today's rule include:

           Category            Examples of potentially affected entities
State, Territorial, and        States, Territories, and Tribes
 Indian Tribal Governments.     authorized to administer the NPDES
                                permitting program; States, Territories,
                                and Tribes providing certification under
                                Clean Water Act section 401;
                               State, Territorial, and Indian Tribal
                                owned facilities that must conduct
                                monitoring to comply with NPDES permits.
Industry.....................  Facilities that must conduct monitoring
                                to comply with NPDES permits.
Municipalities...............  POTWs or other municipality owned
                                facilities that must conduct monitoring
                                to comply with NPDES permits.

    This table is not intended to be exhaustive, but rather provides a 
guide for readers regarding entities likely to be affected by this 
action. This table lists types of entities that EPA is now aware of 
that could potentially be affected by this action. Other types of 
entities not listed in the table could also be affected. To determine 
whether your facility is affected by this action, you should carefully 
examine the applicability language at 40 CFR 122.1 (NPDES purpose and 
scope), 40 CFR 136.1 (NPDES permits and CWA) and 40 CFR 403.1 
(Pretreatment standards purpose and applicability). If you have 
questions regarding the applicability of this action to a particular 
entity, consult the appropriate person listed in the preceding FOR 

B. What should I consider as I prepare my comments for EPA?

    1. Submitting CBI. Do not submit this information to EPA through 
http://www.regulations.gov or email. Clearly mark the part or all of 
the information that you claim to be CBI. For CBI information in a disk 
or CD ROM that you mail to EPA, mark the outside of the disk or CD ROM 
as CBI and then identify electronically within the disk or CD ROM the 
specific information that is claimed as CBI. In addition to one 
complete version of the comment that includes information claimed as 
CBI, a copy of the comment that does not contain the information 
claimed as CBI must be submitted for inclusion in the public docket. 
Information so marked will not be disclosed except in accordance with 
procedures set forth in 40 CFR part 2.
    2. Tips for Preparing Your Comments. When submitting comments, 
remember to:
     Identify the rulemaking by docket number and other 
identifying information (subject heading, Federal Register date and 
page number).
     Follow directions--The agency may ask you to respond to 
specific questions or organize comments by referencing a Code of 
Federal Regulations (CFR) part or section number.
     Explain why you agree or disagree; suggest alternatives 
and substitute language for your requested changes.
     Describe any assumptions and provide any technical 
information and/or data that you used.
     If you estimate potential costs or burdens, explain how 
you arrived at your estimate in sufficient detail to allow for it to be 

[[Page 77744]]

     Provide specific examples to illustrate your concerns, and 
suggest alternatives.
     Explain your views as clearly as possible, avoiding the 
use of profanity or personal threats.
     Make sure to submit your comments by the comment period 
deadline identified.

II. Summary of New Information and Request for Comment

A. Background on Proposed Rule

    On September 23, 2010, EPA proposed to add new and revised EPA 
methods to its Part 136 test procedures (75 FR 58024). The regulated 
community and laboratories use these approved methods for determining 
compliance with National Pollutant Discharge Elimination System (NPDES) 
permits or other monitoring requirements under the Clean Water Act 
(CWA). EPA periodically updates the list of approved methods to reflect 
advances in technology and provide entities more choices of approved 
compliance monitoring methods. Among other methods, in the September 
2010 proposal, EPA proposed to add two oil and grease methods published 
by the Standard Methods Committee that use the same solvent as the 
existing Part 136 oil and grease methods. In the Notice, EPA also 
described three oil and grease methods published by ASTM International 
or the Standard Methods Committee that require a different extractant 
and/or a different measurement (i.e., determinative) technique than the 
existing Part 136 oil and grease methods. As explained in the Notice, 
oil and grease is a method-defined parameter. That is, the measurements 
obtained by the method are a specific artifact of the method and 
defined solely by the elements (solvent, determinative technique) used 
to measure the analyte. Because these three methods use a different 
extractant and/or a different determinative technique, how to translate 
measurements using these methods to those obtained under existing 
methods for purposes of comparison was not clear. Consequently, 
consistent with past practices, EPA did not propose to include these 
methods in Part 136.

B. Method-Defined Analytes

    A method-defined analyte includes certain parameters where the 
measurement results obtained are solely dependent on the method used. 
As a consequence, the results obtained are not directly comparable to 
results obtained by another method (i.e., the data derived from method-
defined protocols cannot be reliably verified outside the method 
itself). EPA has defined a method-defined analyte in 40 CFR 136.6(a)(5) 
as ``.* * * an analyte defined solely by the method used to determine 
the analyte. Such an analyte may be a physical parameter, a parameter 
that is not a specific chemical, or a parameter that may be comprised 
of a number of substances. Examples of such analytes include 
temperature, oil and grease, total suspended solids, total phenolics, 
turbidity, chemical oxygen demand, and biochemical oxygen demand.''

C. Oil and Grease

    Unlike many parameters, oil and grease is not a unique chemical 
entity, but is a mixture of chemical species that varies from source to 
source. Common substances that may contribute to oil and grease include 
petroleum based compounds such as fuels, motor oil, lubricating oil, 
soaps, waxes, and hydraulic oil and vegetable based compounds such as 
cooking oil and other fats. Oil and grease is defined by the method 
used to measure it (i.e., a method-defined analyte). The CWA defines 
oil and grease as a conventional parameter and hundreds of thousands of 
NPDES permits and indirect discharging permits contain oil and grease 
numerical limits. Currently, Part 136 lists three references to 
analytical methods for the measurement of oil in grease in such 
discharge permits. Overwhelmingly, the vast majority of discharges use 
EPA Method 1664A to measure compliance with such discharge limits. 
Method 1664A is a liquid/liquid extraction (LLE), gravimetric procedure 
that employs normal hexane (n-hexane) as the extraction solvent. This 
method also allows the use of solid-phase extraction (SPE) provided 
that the results obtained by SPE are equivalent to the results obtained 
by LLE.

D. Public Comments Related to Oil and Grease

    In response to the September 2010 proposal, EPA received several 
comments recommending that EPA approve recent methods that include new 
technologies, including alternative methods for oil and grease. One 
commenter stated that EPA's reasoning for not approving alternative 
test methods for oil and grease is contradictory to the Agency's 
``Summary'' statement that these regulations will ``provide increased 
flexibility to the regulated community and laboratories in their 
selection of analytical methods (test procedures) for use in Clean 
Water Act programs.'' This commenter added that approving the new 
technologies would be more consistent with EPA's mission and purpose to 
``ensure that all Americans are protected from significant risks to 
human health and the environment where they live, learn and work.''
    Another commenter indicated that EPA should approve new 
technologies for oil and grease because n-hexane is a dangerous 
solvent. This commenter cited literature that describes n-hexane's 
toxicity to humans and to the environment. Still another commenter 
stated that fats, oils and greases are not exclusively ``hexane 
extractable'' compounds and claimed that other technologies and methods 
may be better at measuring these compounds, and may be used to better 
quantify how much fat, oil or grease is toxic to aquatic life or 
interferes with wastewater treatment. This commenter also stated that 
EPA should not specifically and uniquely endorse a solvent-specific 
method for ``oil and grease'' and requested that EPA reverse its 
decision that only n-hexane extractable oil and grease methods are 

III. ASTM Method D7575-10 for Oil and Grease

    Some of the comments focused exclusively on one particular oil and 
grease method EPA discussed in its proposal, ASTM D7575-10. Unlike EPA 
Method 1664A which uses n-hexane as the extractant and gravimetry for 
the measurement of the extracted materials, ASTM D7575-10 uses an 
extracting membrane followed by infrared measurement of the sample 
materials that can be retained on the membrane. This method was 
originally developed by Orono Spectral Solutions (OSS), and approved by 
ASTM on January 1, 2010 (Standard Test Method for Solvent-Free Membrane 
Recoverable Oil and Grease by Infrared Determination, ASTM D7575-10). 
Certain commenters to EPA's September 2010 proposal, including ASTM and 
OSS, requested that EPA re-consider ASTM D7575-10 for the measurement 
of oil and grease under Clean Water Act programs. In particular, they 
cited that ASTM D7575-10 is solvent free and provides reliable and 
comparable results to EPA Method 1664A. As part of this re-
consideration, these commenters submitted additional information on the 
health hazards associated with hexane as well as additional single 
laboratory comparability data between Method 1664A and ASTM D7575-10 
and on additional matrices tested after the initial comparability study 
and associated statistical analysis. These data, EPA's analyses of 
these data, and

[[Page 77745]]

communications related to the alternative ASTM method between EPA, OSS 
and ASTM are included as part of the record for today's notice.
    EPA's consideration of ASTM D7575-10 is entirely novel. Because oil 
and grease is a method-defined parameter, with one exception, EPA has 
not considered promulgating multiple methods to measure oil and grease 
that are based on different extractants. Moreover, EPA has not 
considered multiple oil and grease methods that are based on different 
determinative techniques. The only exception to this was EPA's 
promulgation of EPA Method 1664A in 1999 to replace Method 413.1, a 
similar procedure that used Freon[supreg] (1,1, 2-trichloro-1,2,2-
trifluoroethane (CFC-113; Freon-113)) as the extraction solvent. EPA 
made this exception because Freon[supreg] was banned by an 
international treaty, and until the ban went into effect, EPA allowed 
either of these oil and grease methods for CWA compliance. In both 
methods, the determinative technique is gravimetry and the only change 
was the extraction solvent (n-hexane instead of Freon[supreg]).
    EPA is persuaded by commenters to its September 23, 2010 Notice 
that it should re-consider its position on ASTM D7575-10. Such a 
consideration represents a new path for EPA. As is always the case, EPA 
is proceeding carefully, with a particular focus on the underlying 
data. EPA's consideration is specific to ASTM D7575-10 and should not 
be interpreted broadly to other oil and grease methods that use 
different extractants and/or determinative techniques, or more 
generally to other method-defined analytes. If EPA receives similar 
requests for other methods, it will evaluate each one individually.
    Although the September 2010 proposal discussed the current use of 
EPA Method 1664A as a required testing method to determine the 
eligibility of materials for certain conditional exclusions for RCRA 
regulations under 40 CFR260.20 and 260.22 (i.e., delistings), and 
additionally proposed to allow the revised version of this testing 
method (Method 1664, Rev. B) for future delistings, EPA is not 
considering ASTM D7575-10 for use under the RCRA program. Until ASTM 
D7575-10 is validated for a full range of matrices covered by the RCRA 
program, EPA considers this new testing method to be limited to the 
Clean Water Act program.

A. Technical Considerations Related to ASTM Method D7575-10

1. EPA Evaluation of This New Method
    Based on the data and information available in EPA's record, EPA 
concludes ASTM D7575-10 is a good stand-alone method for the 
measurement of oil and grease in wastewater. The method was single- and 
multi-lab tested following ASTM Standard Practice D2777 (Standard 
Practice for the Determination of Precision and Bias of Applicable Test 
methods of Committee D19 on Water) and produces similar recoveries and 
precision to EPA Method 1664A for those matrices tested and in the 
range of method applicability (5-200 mg/L).
    In reviewing the method, EPA requested that ASTM revise its new 
standard to provide additional details on the underlying procedural 
steps--specifically in regard to sample homogenization and calibration 
verification--and to clarify the applicability (or lack thereof) of the 
method to non-wastewater matrices. ASTM revised the method write-up 
accordingly. See DCN xxx for additional information.
2. Comparability of Results Between ASTM D7575-10 and EPA Method 1664A
    As explained above, with the exception of EPA's promulgation of 
Method 1664A to replace Method 413.1, EPA has not considered 
promulgating multiple methods to measure oil and grease that are based 
on different extractants nor has EPA considered promulgating oil and 
grease methods with different determinative techniques. As a result, 
EPA does not have a defined ``process'' for such considerations. For 
non-method-defined parameters where the analyte being measured is a 
single compound (e.g., copper, benzene), EPA often promulgates multiple 
methods that may be based on different determinative techniques for 
nationwide use. In such cases, EPA has a well-defined process for 
ensuring that the performance of a proposed method is acceptable (i.e., 
the proposed test procedure must demonstrate an improvement over 
current EPA-approved methods such as fewer matrix interferences, and 
better sensitivity, precision and recovery). For a new candidate test 
method employing a determinative technique that is different from those 
techniques used in existing approved methods, the applicant must 
develop quality control (QC) acceptance criteria based on the 
validation protocol for nationwide use applications (9 laboratories, 
each analyzing a different matrix). The QC acceptance criteria for the 
candidate method must then be compared to the QC acceptance criteria 
specifications for methods in Part 136 and the performance of the 
candidate method must be as good or better than that of an approved 
method. This process is described in the ``Protocol for EPA Approval of 
New Methods for Organic and Inorganic Analytes in Wastewater and 
Drinking Water,'' March 1999.
    In contrast, there is no well-defined process for the evaluation of 
a proposed test method for method-defined parameters. In addition to 
ensuring that the performance of the proposed method is acceptable as 
described above for non-method-defined parameters, EPA wants to ensure 
that results produced by the proposed method are comparable to results 
produced with the approved method. When EPA promulgated EPA Method 
1664A to replace EPA Method 413.1, a similar procedure that used 
Freon[supreg] (1,1, 2-trichloro-1,2,2-trifluoroethane (CFC-113; Freon-
113)) as the extraction solvent, EPA evaluated a variety of possible 
replacement extracting solvents in addition to n-hexane. EPA selected 
n-hexane and promulgated Method 1664A after conducting extensive side-
by-side studies of several extracting solvents on a variety of samples 
representing a wide range of matrices (see ``Preliminary Report of EPA 
Efforts to Replace Freon for the Determination of Oil and Grease,'' 
EPA-821-R-93-011, September 1993, and Report of EPA Efforts to Replace 
Freon for the Determination of Oil and Grease and Total Petroleum 
Hydrocarbons, EPA-820-R-95003, April 1995). In considering which 
solvent produced results most comparable to results obtained with 
Freon[supreg], EPA conducted a Root Mean Squared Deviation (RMSD) 
evaluation of the data collected in the side-by-side studies. None of 
the alternative solvents produced results statistically comparable to 
results produced by Freon[supreg]. However, EPA concluded at the time 
that n-hexane was appropriate as an alternative solvent, based on 
overall extraction results (96% versus 100% for Freon) and analytical 
practical considerations (e.g., boiling point).
    In considering ASTM D7575-10, EPA reviewed the available single 
laboratory comparability data between ASTM D7575-10 and EPA Method 
1664A. Initially, these data included triplicate analyses of samples 
from seven different wastewater matrices (eight POTWs, dairy, machine 
shop, gunsmith, auto garage, auto salvage yard, and fish processor). 
Later, OSS submitted

[[Page 77746]]

additional data for three matrices (bilge water, peanut processor, and 
lunchmeat processor) that were collected after the single laboratory 
study.\1\ EPA conducted a Root Mean Squared Deviation (RMSD) 
comparability assessment with these data, following the methodology set 
forth in ``Analytical Method Guidance for EPA Method 1664A 
Implementation and Use (40 CFR part 136), EPA/821-R-00-003, February 
2000.'' For this assessment, EPA first used the original data set and 
subsequently included the additional data for three matrices and 
determined the results were not statistically comparable, with or 
without the data for the additional matrices. This outcome was not 
unexpected because of the intrinsic differences in the two methods and 
the nature of method-defined parameters. Similarly, when EPA performed 
an RMSD comparability assessment before promulgating EPA Method 1664A 
in place of EPA Method 413.1, EPA did not find the results to be 
statistically comparable.\2\

    \1\ OSS also submitted data for several other matrices that EPA 
did not include in the analysis because these data were based on 
only one sample result per matrix and thus lacked the required 
replicates for a statistical analysis. Additionally, ASTM recently 
submitted triplicate data for three other matrices. Because EPA 
received this data after conducting its statistical analysis, this 
data is not included in the RMSD assessment described in this 
paragraph, but is included in the record for today's notice.
    \2\ Note that in absence of statistical comparability, EPA 
ultimately determined that EPA Method 1664A could be used as a 
direct replacement for EPA Method 413.1.

    As explained in Section II.B, the comparability of results is a 
significant issue with method-defined analytes such as oil and grease 
because the results depend on the method used. For oil and grease, the 
amount of oil and grease material extracted depends on the solvent or 
membrane used for the extraction of oil and grease. As such, it may not 
be possible for results from methods that use different extraction 
techniques to be compared statistically. For example, EPA Method 1664A 
employs distillation at 85[deg]C, and as such, petroleum materials from 
gasoline through 2 fuel oil and non-petroleum materials 
including carboxylic and other organic acids may be partially lost 
during this solvent removal operation. Similarly, some crude oils and 
heavy fuel oils contain a significant percentage of materials that are 
not soluble in the n-hexane solvent of EPA Method 1664A resulting in 
low recoveries for these materials. ASTM D7575-10 has no such solvent 
removal step which could increase or decrease the amount of petroleum 
and non-petroleum materials measured by ASTM D7575-10 relative to 
Method 1664A.
    For the reason identified above, in the case of ASTM D7575-10, EPA 
concludes it is not appropriate to apply the same statistical 
assessment as is done for non-method-defined parameters. As a result, 
EPA applied similar comparison techniques as those performed in 
replacing EPA Method 413.1 with EPA Method 1664A. As mentioned above, 
during that replacement analysis, n-hexane was found to extract 96% of 
the oil and grease that could be extracted by Freon. This 4% difference 
was deemed insignificant based on the variability of oil and grease 
measurements (around the order of 10% relative standard deviation) and 
the confidence intervals about the 96% extraction (plus or minus 20% 
extracted). When comparing the results of ASTM D7575-10 to EPA Method 
1664A, the non-solvent method removes an average of 99.6% of the oil 
and grease that was removed by n-hexane under the same conditions. The 
variability of the situational comparisons along with the 10% relative 
standard deviation for oil and grease measurements once again allow us 
to conclude that the 0.4% difference is not significant. Using this 
approach, for the range of the ASTM D7575-10 applicability (5-200 mg/
L), ASTM D7575-10 could serve as a substitute for Method 1664A in the 
same fashion as n-hexane served as a replacement for Freon.

B. Summary of EPA's Reconsideration of ASTM D7575-10

    Based on the information presented in today's Notice, EPA is re-
considering its decision not to include ASTM D7575-10 in 40 CFR Part 
136 as an alternative to EPA Method 1664A for measuring oil and grease. 
EPA has three main reasons for this reconsideration. First, EPA's 
analysis demonstrates ASTM D7575-10 is an acceptable stand-alone method 
for the measurement of oil in grease in wastewater for the applicable 
reporting range (5-200 mg/L) and it produces results that are generally 
very close to those obtained using EPA Method 1664A for the matrices 
tested. Second, this method has certain advantages over the currently 
approved method. EPA supports pollution prevention, and is particularly 
persuaded by the substantial advantages associated with the green 
aspects of this membrane technology (e.g., it uses a solventless 
extraction, there is no solvent waste, and no analyst exposure to 
solvent). Finally, ASTM D7575-10 may offer other advantages such as 
ease of analysis, reduced analysis time, and lower analytical costs.

C. Implementation Considerations Related to Multiple Oil and Grease 

    EPA recognizes that if it promulgates ASTM D7575-10 in 40 CFR Part 
136 as an alternative to EPA method 1664A, permittees and control 
authorities may still have concerns related to the results obtained 
from ASTM D7575-10 relative to EPA Method 1664A, particularly for 
matrices not evaluated to date. While EPA has determined that the 
results of the two methods are comparable over the applicable range 
where the two methods overlap (5-200 mg/L), because of the wide variety 
and type of individual compounds that may be measured by oil and grease 
and because oil and grease are extensively incorporated in permits 
covering a wide variety of wastewater matrices, permittees or control 
authorities may continue to have compliance concerns (i.e., a permittee 
could be in or out of compliance) simply due to a change in the test 
method used to evaluate samples.
    When EPA promulgated EPA Method 1664A to replace EPA Method 413.1, 
EPA and other stakeholders had similar concerns. These concerns were 
magnified because Method 1664A was a replacement, rather than an 
alternative, to the existing method at that time. To accommodate 
concerns about differences in results, EPA allowed permitting 
authorities to establish a conversion factor by having the discharger 
perform a side-by-side comparison of Method 1664 and the Freon[supreg] 
extraction method and then adjusting the discharge limits, if 
necessary, to account for differences in the permit. EPA further 
recommended a specific process to follow for the side-by-side 
comparison in the guidance document mentioned earlier [Analytical 
Method Guidance for EPA Method 1664A Implementation and Use (40 CFR 
part 136), EPA/821-R-00-003, February 2000].
    In contrast to EPA's replacement of Freon with n-hexane, if EPA 
were to promulgate ASTM D7575-10, it would not lead to any requirement 
on permit holders. In this case, unless ASTM D7575-10 is specified in 
the permit, promulgating ASTM D7575-10 would simply provide additional 
flexibility to permit holders in analyzing for oil and grease. Because 
this would be optional and because of the burden that would be placed 
on the permitting authorities in reviewing side-by-side data, EPA is 
not currently persuaded that it should include a provision providing 
the same

[[Page 77747]]

ability to adjust discharge limits based on side-by side-comparison of 
EPA Method 1664A to ASTM D7575-10 as it did when it replaced Freon with 
n-hexane. However, to the extent that permittees would elect to use 
ASTM D7575-10 and permitting authorities would accept the use of ASTM 
D-7575-10 rather than EPA Method 1664A, nothing would prevent them from 
conducting a side-by-side comparison of the two methods. EPA would 
recommend such a side-by-side comparison if permittees and/or 
permitting authorities have concerns about a specific matrix, 
particularly when the measured oil and grease values when switching to 
ASTM D7575-10 are more than 20% lower from values routinely measured by 
EPA Method 1664A (the 20% variability around oil and grease 
measurements is discussed in section III.A.2 of today's Notice).

IV. Request for Comments

    Based on the new information and EPA's analysis of this information 
as described in this Notice, EPA is reconsidering whether to promulgate 
ASTM D7575-10 in 40 CFR Part 136 as an alternative method for oil and 
grease where the applicable ranges overlap (5-200 mg/L) and requests 
public comments on this reconsideration, the supporting data, and the 
resulting analysis. While ASTM D7575-10 has significant pollution 
prevention advantages over the currently approved method, EPA 
recognizes the potential impact that this new method could have on the 
hundreds of thousands of oil and grease determinations in regulatory 
Clean Water Act programs and desires to obtain additional input from 
stakeholders. Specifically, EPA requests comments on the following:
    1. Whether EPA should reconsider promulgating this additional 
method for oil and grease based on different extractants and 
determinative techniques than EPA Method 1664A.
    2. EPA's current view, based on the data it has reviewed to date, 
that ASTM D7575-10 is an acceptable choice for the determination of oil 
and grease for the range (5 to 200 mg/L) evaluated.
    3. EPA's current conclusion that permit limit adjustment based on 
side-by-side comparisons of EPA Method 1664A and ASTM D7575-10 is not 
appropriate. EPA is particularly interested in obtaining comments from 
permitting authorities on this issue and estimates of the burden 
associated with reviewing such requests.
    4. If EPA were to allow a side-by-side comparison with limit 
adjustment as necessary, should EPA look to the approach used for n-
hexane in place of Freon (see section III.C above) or should EPA 
consider a different approach?

V. Referenced New Docket Materials

1. January 16, 2009 Memorandum from Richard Reding on Modifications 
to Method 1664A.
2. May 14, 1999 Federal Register (64 FR 26315).
3. Preliminary Report of EPA Efforts to Replace Freon for the 
Determination of Oil and Grease, EPA-821-R-93-011, September 1993.
4. Report of EPA Efforts to Replace Freon for the Determination of 
Oil and Grease and Total Petroleum Hydrocarbons: Phase II, EPA-820-
R-95-003, April 1995.
5. October 15, 2010 email from Tyler Martin containing the following 
data files:
    a. Multi-Lab Validation Raw Data
    b. Expanded ASTM D7575 Validation Report
    c. Single-Lab Validation Raw Data
    d. Comparability Analysis from Single-Lab Validation Results
6. October 19, 2010 email from Tyler Martin containing additional 
comparability data between Method 1664 and ASTM D7575.
7. October 21, 2010 email from Tyler Martin with clarification on 
data submitted.
8. June 28, 2011 letter from James A. Thomas, ASTM President to Mary 
Smith, EPA, with ASTM International D19 Water Response to US EPA 
Questions Concerning ASTM Standard D7575.
9. Analytical Method Guidance for EPA Method 1664A Implementation 
and Use (40 CFR part 136), EPA/821-R-00-003, February 2000.
10. Protocol for EPA Approval of New Methods for Organic and 
Inorganic Analytes in Wastewater and Drinking Water, March 1999.
11. Study Report from the Testing of Additional Industrial 
Wastewater Matrices in Support of ASTM D7575 for USEPA's 
Reconsideration of this Method in the Forthcoming Method Update 
Rule, November 2011.

    Dated: December 2, 2011.
Nancy K. Stoner,
Acting Assistant Administrator for Water.
[FR Doc. 2011-32063 Filed 12-13-11; 8:45 am]