Document ID: EPA-HQ-OW-2010-0192-0363
Agency: epa
Document Type: Rule
Title: Analysis and Sampling Procedures: Guidelines Establishing Test Procedures for the Analysis of Pollutants under the Clean Water Act
Posted Date: 2013-03-06T05:00Z

[Federal Register Volume 78, Number 44 (Wednesday, March 6, 2013)]
[Rules and Regulations]
[Pages 14457-14461]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2013-05248]

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

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 136

[EPA-HQ-OW-2010-0192; FRL-9787-7]

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

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice of final decision.

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

SUMMARY: EPA discussed, but did not propose, a new method, ASTM D7575, 
for oil and grease in the 2010 proposed Methods Update Rule (MUR). Oil 
and grease is a method-defined parameter. That is, the nature and 
amount of material determined by the method is defined in terms of the 
method. EPA subsequently published a Notice of Data Availability (NODA) 
on this method that provided new data and requested comment on whether 
and how EPA should approve the method in Part 136 as an alternative oil 
and grease method. This document provides EPA's final decision on its 
reconsideration of this method.

DATES: March 6, 2013.

FOR FURTHER INFORMATION CONTACT: Jan Matuszko, Office of Science and 
Technology, Office of Water (4303-T), Environmental Protection Agency, 
1200 Pennsylvania Avenue NW.; Washington, DC 20460; telephone number: 
202-566-1035; fax number: 202-566-1053; email address: 
matuszko.jan@epa.gov.

SUPPLEMENTARY INFORMATION: 

I. Background

A. CWA Analytical Methods and Limited Use Alternate Test Procedures 
(ATP) Program

    EPA establishes test procedures (also referred to as analytical 
methods) codified in 40 CFR Part 136 under its authority in section 
304(h) of the CWA to promulgate guidelines establishing test procedures 
for the analysis of pollutants. EPA's regulations provide that, when 
EPA has promulgated a test procedure for analysis of a specific 
pollutant in 40 CFR Part 136, an NPDES permittee must use an approved 
test procedure for the specific pollutant when measuring the pollutant 
for an application submitted to EPA or to a State with an approved 
NPDES program and for reports required to be submitted by dischargers 
under the NPDES program. See 40 CFR Sec.  136.1(a). This approach 
simplifies the permitting process for hundreds of thousands of NPDES 
and indirect discharging permittees and permitting authorities. In the 
absence of an approved test procedure for a specific pollutant (or when 
an approved test procedure does not work in a specific matrix, e.g., 
because of a matrix interference), generally, a permit applicant may 
use any suitable method but must provide the permitting authority a 
description of the method for evaluation of its suitability. See 40 CFR 
122.21(g)(7). However, 40 CFR Part 136 also recognizes that new 
technologies and approaches are constantly being developed, including 
methods for pollutants for which EPA already has an approved test 
procedure. As such, Part 136.5 allows for use of an alternate method 
for a specific pollutant or parameter in a regulated CWA matrix that is 
different from the approved test procedure (i.e., limited use 
approval). Requests for such uses, along with supporting data, are made 
to the applicable Regional Alternate Test Procedure (ATP) Coordinator 
for consideration and approval.

B. 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., it is 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 two analytical 
methodologies for the measurement of oil and grease in such discharge 
permits. Permittees have been using 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 that is applicable for measuring oil 
and grease in concentrations from 5 mg/L to 1,000 mg/L. 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.

C. Method-Defined Analytes

    The measurement results obtained for a method-defined analyte are 
both

[[Page 14458]]

specific to that method and solely dependent on the method used. As a 
consequence, the results obtained for a parameter defined by one 
particular method are not necessarily 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.''

D. EPA's Past Consideration of Alternative Oil and Grease Methods for 
Adoption in 40 CFR Part 136

    Because oil and grease is a method-defined parameter, 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 EPA Method 413.1 
(64 FR 26315), 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 (the Montreal Protocol on Substances That Deplete 
the Ozone Layer), 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]).
    When EPA promulgated EPA Method 1664A to replace EPA Method 413.1, 
EPA evaluated a variety of possible replacement extracting solvents in 
addition to n-hexane. EPA selected n-hexane and promulgated Method 
1664A after conducting multi-year, extensive side-by-side studies on a 
variety of samples representing a wide range of matrices/discharges 
(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: Phase II,'' EPA-820-R-
95-003, 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).
    To accommodate concerns about possible differences in results, EPA 
allowed permitting authorities to establish a conversion factor by 
having the discharger perform a side-by-side comparison of Method 1664A 
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 for Method 1664A (see 
``Analytical Method Guidance for EPA Method 1664A Implementation and 
Use (40 CFR part 136),'' EPA/821-R-00-003, February 2000).

E. Proposed 2010 Methods Update Rule (MUR)

    On September 23, 2010, EPA proposed to add new and revised EPA 
methods to its Part 136 test procedures (75 FR 58024). Among other 
methods, in the September 2010 proposal, EPA 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. These methods were ASTM D7575, ASTM D7066 and 
Standard Methods 5520. Section 12(d) of the National Technology 
Transfer and Advancement Act (NTTAA) of 1995 (Pub. L. 104-113; 15 
U.S.C. 272 note) directs EPA to use voluntary consensus standards in 
its regulatory activities unless to do so would be inconsistent with 
applicable law or is otherwise impractical. As such, when requested by 
ASTM and Standard Methods to include their methods in 40 CFR Part 136, 
EPA may propose to approve a method or explain why it should or should 
not do so. The proposal explained the issues surrounding method-defined 
parameters, and explained that, consistent with past practices, EPA was 
not proposing to include any of the three oil and grease methods in 
Part 136, including ASTM D7575.

F. December 2011 Notice of Data Availability (NODA)

    In response to the September 2010 proposal, EPA received comments 
recommending that it reconsider alternative methods for oil and grease. 
Some of the comments focused exclusively on the oil and grease method 
ASTM D7575. Unlike EPA Method 1664A which uses n-hexane as the 
extractant and gravimetry for the measurement of the extracted 
materials, ASTM D7575 uses an extracting membrane followed by infrared 
measurement of the sample materials that can be retained on the 
membrane. In particular, commenters cited that ASTM D7575 is solvent 
free and provides reliable and comparable results to EPA Method 1664A. 
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 and on 
additional matrices tested after the initial comparability study and 
associated statistical analysis.
    Because EPA is interested in promoting the use of solvent-free 
methods and this new information, EPA re-evaluated the ASTM D7575 
method for the measurement of oil and grease and published a Notice of 
Data Availability on December 14, 2011 (76 FR 77742). The notice 
provided the additional data and EPA's analysis of that data. Further, 
it explained that, after evaluating the new information, EPA was re-
considering its decision not to include ASTM D7575 in 40 CFR Part 136 
as an alternative to EPA Method 1664A for measuring oil and grease. The 
notice explained that EPA had three primary reasons for this re-
consideration. First, EPA's analysis demonstrates ASTM D7575 is an 
acceptable stand alone method for the measurement of oil and grease in 
wastewater for its applicable reporting range (5-200 mg/L). Second, it 
produces results that, while not statistically comparable across all 
matrices tested,\1\ are generally very close to those obtained using 
EPA Method 1664A for the matrices tested. Third, 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

[[Page 14459]]

solvent waste, and no exposure of the analyst to solvent).
---------------------------------------------------------------------------

    \1\ Similar to the approach it used when it replaced Freon with 
hexane, EPA performed a RMSD evaluation of the ASTM D-7575 results 
and EPA Method 1664A results for the available matrices evaluated. 
See 76 FR 77745.
---------------------------------------------------------------------------

    However, the notice also discussed implementation considerations 
associated with promulgating an alternative method based on a different 
determinative step for a method-defined parameter. EPA recognized 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, as such, was keenly interested in obtaining 
additional input from stakeholders. Therefore, the notice explained 
that, while EPA determined that the results of the EPA 1664A and ASTM 
D7575 are comparable over the applicable range where the two methods 
overlap (5-200 mg/L) for the set of the 13 wastewater matrices 
evaluated, it continued to have compliance concerns with promulgating 
the ASTM method for nationwide use as an alternative to EPA Method 
1664A. More specifically, because oil and grease measures a wide 
variety and type of individual compounds and because oil and grease is 
extensively incorporated in permits covering a wide variety of 
wastewater matrices, the result of promulgating the ASTM D7575 method 
as an alternative to EPA Method 1664A is that a permittee could be in 
or out of compliance simply due to a change in the test method used to 
evaluate samples.
    Finally, through the notice, EPA requested comment on its 
conclusion that ASTM D7575 is an acceptable choice for the 
determination of oil and grease, and whether it should reconsider its 
policy towards method-defined parameters for this particular method. In 
particular, the notice requested comment on whether or not EPA should 
reconsider promulgating this specific additional method for oil and 
grease based on different extractants and determinative techniques than 
EPA Method 1664A. Further, in the event that EPA were to promulgate 
this specific alternative method, the notice requested comment on some 
approaches that could ensure comparability for individual permittees 
(e.g., EPA requested comment on the need for a permit adjustment based 
on side-by-side comparison of Methods 1664A and ASTM D7575).

G. Summary of NODA Comments

    EPA received comments from 106 stakeholders. Approximately, a third 
expressed support for nationwide approval of the ASTM D7575 method as 
an alternative oil and grease method. In general, these comments were 
similar to those received on EPA's proposal: ASTM D7575 is ``green'' 
(e.g., less hazardous waste, no exposure to toxic chemicals), it is 
easier, faster, less expensive and potentially portable in comparison 
to EPA 1664A, and it produces results substantially in agreement with 
Method 1664A. About two-thirds of the comments recommended EPA not 
approve it for use as an alternative oil and grease method. Some 
comments were specific to the sampling requirements and sample 
preparation procedures of the method, raising technical concerns such 
as the representativeness of the 10 mL aliquot and concerns over the 
drying procedures. Some comments were more overarching such as comments 
that ASTM D7575 had not been tested in a sufficient number of matrices. 
Others were specific to the consideration of the ASTM D7575 method as 
an alternative to EPA method 1664A, such as the applicable range of the 
ASTM D7575 method (5 to 200 mg/L) was limited in comparison to EPA 
Method 1664A. Some noted that the ASTM method did not produce 
statistically comparable results to EPA Method 1664A and EPA should 
retain its policy not to approve alternative methods for method-defined 
parameters that are not based on the same determinative step. Finally, 
many shared the concerns raised in the notice about implementing ASTM 
D7575 on a nationwide basis as an alternative oil and grease method and 
the possibility that a discharger could be in or out of compliance 
simply by changing the method.

III. Final Determination on ASTM D7575 as an Alternative to Existing 
Part 136 Oil and Grease Methods

    As explained in the NODA, EPA's consideration of ASTM D7575 
represents a unique situation. Because oil and grease is a method-
defined parameter, 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 to replace Method 
413.1, a similar procedure that used (the internationally banned 
extraction solvent) Freon[supreg]. Thus, EPA's consideration of ASTM 
D7575 as an alternative oil and grease method represents a new path for 
EPA. As is always the case, EPA proceeded carefully, with a particular 
focus on the underlying data. This consideration is specific to ASTM 
D7575 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.

A. ASTM D7575 Is a Good Stand Alone Method for the Measurement of Oil 
and Grease in Aqueous Matrices

    After careful consideration of all the comments received on the 
NODA, EPA continues to conclude that ASTM D7575 is a good stand alone 
method for the measurement of oil and grease as defined by the method. 
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 
produced recoveries and precision as good as or better than EPA Method 
1664A for those matrices tested and in the range of ASTM D7575 
applicability (5-200 mg/L). Further, EPA is not persuaded by the 
technical comments it received on the method itself. For example, the 
representativeness of a well homogenized sample used was adequately 
demonstrated by the replicate studies in the validation tests. See 
docket number EPA-HQ-OW-2010-0192 for responses to these and all other 
NODA comments.

B. ASTM D7575 as an Alternative Oil and Grease Method in 40 CFR Part 
136

    After careful consideration of all the comments received on the 
NODA, EPA concludes that the case has not yet been made that ASTM D7575 
should be approved for nationwide use as an alternative oil and grease 
method. EPA has multiple reasons supporting this conclusion. First, 
ASTM D7575 is not applicable to the same range and matrices as the 
existing Part 136 oil and grease methods. ASTM D7575 is applicable for 
measuring oil and grease from 5 mg/L to 200 mg/L while EPA Method 1664A 
is applicable for measuring oil and grease from 5 mg/L to 1,000 mg/L. 
Additionally, as explained in Note 2 in the method, ASTM D7575 is not 
appropriate for certain samples where the solid matter is not 
sufficiently IR transmitting, such as those that contain high levels of 
metal particulates. Further, EPA Method 1664A also quantifies non-polar 
oil and grease (SGT-HEM) while ASTM D-7575 does not.
    Second and more importantly, EPA continues to share the concerns 
raised by many commenters. Given that the two methods measure a method-
defined parameter, by definition, they cannot measure the same thing. 
Consequently, because of the wide variety and type of

[[Page 14460]]

individual compounds that may be measured as oil and grease and because 
oil and grease is extensively incorporated in permits covering a wide 
variety of wastewater matrices, a permittee could be in or out of 
compliance simply due to a change in the test method used to evaluate 
samples. EPA continues to conclude such concerns are well founded for 
the following reasons. First, oil and grease is a method-defined 
parameter. That is, the results are dependent on the particular method 
used. As ASTM D7575 uses a different determinative step than the 
existing approved methods, one would not expect the results to be the 
same for all applications. Second, the results of ASTM D7575 have been 
evaluated on a relatively limited number of matrices (13) in comparison 
to the extensive number and types of possible applications. In 
contrast, when EPA promulgated Method 1664A to replace the previous 
Freon-based method, it evaluated the two methods on a much more 
extensive and wide variety of matrices (approximately 35). Third, the 
data evaluated to date demonstrate that while ASTM D7575 produces 
results that are generally very close to the approved method for the 
set of matrices evaluated, they are not statistically comparable 
results. As such, the concerns that the two methods may produce 
different results are well founded.
    However, EPA also recognizes that a blanket conclusion that one can 
never promulgate new methods for method-defined parameters based on a 
different determinative technique leaves little room for technology 
improvements. Furthermore, EPA is keenly interested in supporting the 
development and use of ``green'' methods such as ASTM D7575 that do not 
require solvents. As such, EPA considered various approaches for 
allowing its use as an alternative to approved methods while minimizing 
the well founded concern that the two methods may affect compliance. In 
other words, in those applications where the two methods produce 
results that are comparable enough not to affect compliance, EPA wants 
to encourage the use of non-solvent based methods such as ASTM D7575. 
On the other hand, EPA wants to prevent the use of ASTM D7575 in those 
applications where the two methods differ in their results and have the 
potential to affect a facility's compliance status. Here, there simply 
is not enough data to make a nationwide determination. Until such time 
that EPA has enough data to make such a determination, EPA has 
concluded such determinations should be made on a case by case basis 
rather than a nationwide basis. As a result, EPA has decided not to 
approve ASTM D7575 as an alternative oil and grease method in Part 136.
    EPA also considered a novel approach in which it would approve ASTM 
D7575 as an alternative oil and grease method in Part 136 with a 
requirement to demonstrate comparability (side-by-side data) to the 
permitting authority. To determine comparability for a specific 
application, a permittee could use the specific side by side comparison 
procedures recommended in the guidance document that was developed when 
Method 1664A was promulgated (see''Analytical Method Guidance for EPA 
Method 1664A Implementation and Use (40 CFR part 136),'' EPA/821-R-00-
003, February 2000). Under this approach, a permittee would only be 
able to use ASTM D7575 if the recommended procedures demonstrated 
comparability. This approach would provide for a non-solvent based 
alternative to measuring oil and grease and eliminate the compliance 
concerns noted above. This approach would be novel because EPA has 
never approved a method for nationwide use with such a requirement. As 
explained in Section II.A, the purpose of promulgating Part 136 methods 
for nationwide use is to simplify the permitting process and reduce 
burden to the permittees and the permitting authority (often the 
state). As a result, EPA consulted with various permitting authorities 
on this consideration. Feedback from permitting authorities indicated 
that reviewing side by side comparison data would be a huge burden on 
the states and that many POTWs lack both the expertise and staff to 
conduct a side by side comparison. As a result, EPA rejected this 
approach.

C. ASTM D7575 as an Alternative Oil and Grease Method in Permit 
Specific Applications

    In EPA's effort to promote the use of newer and more efficient 
methods, EPA looked at a third option--the use of EPA's Alternate Test 
Procedures process spelled out in the regulations at 40 CFR 136.5. EPA 
considered this approach for encouraging and allowing the use of ASTM 
D7575 while eliminating the associated compliance concerns using 
existing regulatory authority. As explained in Section F, EPA 
recognizes that new technologies and approaches are constantly being 
developed and, as such, Part 136 currently allows for permittees to 
gain approval of the use of an alternate method for a specific 
application at a facility or type of discharge that is different from 
the approved test procedure. Therefore, the authority already exists 
under Sec.  136.5 for a permittee to request the use of ASTM D7575 as 
an alternative oil and grease method for a specific use (i.e. limited 
use ATP). The burden to review such requests rests on the EPA Regional 
ATP Coordinators rather than the permitting authority which is often a 
state or a local control authority. As such, EPA encourages permittees 
to carefully consider whether or not ASTM D7575 is an acceptable 
alternative to the existing methods for their specific matrix and, if 
supported by data, to make such requests to their Regional ATP 
Coordinator. To the extent that such requests are widespread, EPA 
headquarters will provide technical support to the Regional ATP 
Coordinators.
    Part 136 already stipulates that an applicant must provide 
comparability data for the performance of the proposed method compared 
to the reference method to eliminate compliance concerns. EPA 
anticipates that requests for the use of ASTM D7575 as an alternative 
oil and grease method could be widespread, thus EPA wants to ensure 
that such requests are handled consistently. To that end, EPA 
recommends that applicants demonstrate comparability by conducting a 
side-by-side comparison using the specific procedures (e.g. sampling 
frequency, number of samples, QA/QC, and statistical analyses) 
recommended in the guidance document that was developed when Method 
1664A was promulgated [Analytical Method Guidance for EPA Method 1664A 
Implementation and Use (40 CFR part 136), EPA/821-R-00-003, February 
2000]. Comparability could be shown if this side by side comparison 
demonstrates there is not a significant difference between the 
promulgated method and ASTM D7575. Finally, EPA notes that such 
requests may provide sufficient additional data that may allow EPA at a 
later date to later make a nationwide determination on the approval of 
ASTM D7575 as an alternative oil and grease method.

IV. New Docket Materials

1. Response to Comment document
2. Response from ASTM re: technical questions
3. Memo describing outreach to states and control authorities on burden
4. May 14, 1999 Federal Register (64 FR 26315)
5. ``Analytical Method Guidance for EPA Method 1664A Implementation and 
Use (40 CFR

[[Page 14461]]

part 136),'' EPA/821-R-00-003, February 2000

    Dated: February 27, 2013.
Nancy K. Stoner,
Acting Assistant Administrator.
[FR Doc. 2013-05248 Filed 3-5-13; 8:45 am]
BILLING CODE 6560-50-P