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Guidelines Establishing Test Procedures for the Analysis of Pollutants and National Primary Drinking Water Regulations; Flexibility in Existing Test Procedures and Streamlined Proposal of New Test Procedures

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

 [Federal Register: March 28, 1997 (Volume 62, Number 60)]
[Proposed Rules]
[Page 14975-15049]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr28mr97_dat-28]



[[Page 14975]]

_______________________________________________________________________

Part II

Environmental Protection Agency

_______________________________________________________________________

40 CFR Parts 136 and 141

Guidelines Establishing Test Procedures for Analysis of Pollutants and
National Primary Drinking Water Regulations; Flexibility in Existing
Test Procedures and Streamlined Proposal of New Test Procedures;
Proposed Rule

[[Page 14976]]

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 136 and 141

[FRL-5800-2]
RIN 2040-AC93


Guidelines Establishing Test Procedures for the Analysis of
Pollutants and National Primary Drinking Water Regulations; Flexibility
in Existing Test Procedures and Streamlined Proposal of New Test
Procedures

AGENCY: Environmental Protection Agency.

ACTION: Proposed rule.

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

SUMMARY: The Environmental Protection Agency (EPA) proposes to
streamline the process for EPA approval of analytical methods (and
modifications thereof) under the Clean Water Act (CWA) and the Safe
Drinking Water Act (SDWA). The current methods approval process applies
to and is used by public and private laboratories, manufacturers of
analytical equipment and analysts who modify analytical methods or who
develop new methods for use in compliance monitoring under the CWA and
SDWA. The proposed rule only affects states if they choose to adopt the
proposed streamlined process as part of their laboratory auditing
programs. Under the streamlined methods approval system, EPA would
increase the analyst's flexibility to modify existing test procedures,
expedite approval of new and modified test procedures, establish and
require the use of standardized quality control (QC) and QC acceptance
criteria in existing and new test procedures, and recommend use of
standard data elements for reporting test results. Today's action
responds to the Administration's Environmental Technology and
Reinventing Government Initiatives and the National Technology Transfer
and Advancement Act by promoting use of emerging technologies and
encouraging participation of consensus standards organizations and
other organizations in developing test procedures (analytical methods).
The action proposed in today's rule would increase the options
available to the regulated community in complying with EPA regulations
under the CWA and SDWA. These actions are only an initial and interim
step in the Agency's pursuit of a performance-based approach to
environmental measurements, and are not meant to define or limit the
Agency's ultimate implementation of a ``pure'' performance-based
measurement system. The increased flexibility provided by this proposed
action should significantly reduce the need for Agency review of
alternate test procedures and make it easier for the analyst to select
analytical methods that are most suited to specific regulatory
measurement needs.

DATES: Comments on this proposed rule will be accepted until June 26,
1997.

ADDRESSES: Send written comments to the Streamlining Methods Docket
Clerk, Water Docket (MC-4101), USEPA, 401 M Street, SW., Washington, DC
20460. Please submit an original and three copies of your comments and
enclosures (including references). 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) or
sections in the proposed regulation or in the supporting documents to
which each comment refers. Commenters should use a separate paragraph
for each issue discussed. Commenters who want EPA to acknowledge
receipt of their comments should enclose a self-addressed, stamped
envelope. No facsimiles (faxes) or electronic mail (email) will be
accepted because EPA cannot ensure that they will be submitted to the
Water Docket. A copy of the supporting documents cited in this proposal
are available for review at EPA's Water Docket, 401 M Street, SW.,
Washington, DC 20460. For access to docket materials, call 202/260-3027
between 9:00 a.m. and 3:30 p.m. for an appointment.

FOR FURTHER INFORMATION CONTACT: Dr. Richard Reding, USEPA, Office of
Ground Water and Drinking Water (MS-140), 26 W. Martin Luther King
Drive, Cincinnati, OH 45268, 513/569-7961.

SUPPLEMENTARY INFORMATION: The supporting documents that are a part of
the administrative record for this proposal may be obtained from the
National Center for Environmental Publications and Information (NCEPI)
(513/489-8190), from the National Technical Information Service (NTIS)
(703/487-4650), from the Educational Resources Information Center
(ERIC) (800/276-0462), and via the Internet on the EPA Office of Water
home page at http://www.epa.gov/watrhome. These documents are titled,
Guide to Method Flexibility and Approval of EPA Water Methods, December
1996 Draft, EPA-821-D-96-004, NTIS PB97-117766, ERIC D-A43 or D-A46
(diskette) (Streamlining Guide, EPA 1996a), Methods for Organic
Chemical Analysis of Municipal and Industrial Wastewater, December
1996, EPA-821-B-96-005, NTIS PB97-125298, ERIC D-A44 or D-A47
(diskette) (Organic Methods, EPA 1996b), and Guidelines and Format for
Methods to Be Proposed at 40 CFR Part 136 or Part 141, July 1996, EPA-
821-B-96-003, NTIS PB96-210448, ERIC D-A42 or D-A45 (diskette) (Method
Guidelines and Format, EPA 1996c).

Regulated Entities

    Entities potentially regulated by this action are those who seek
EPA approval of analytical technologies for monitoring under the
provisions of the CWA and SDWA. Entities potentially regulated by this
action are listed in the table below. These entities potentially
include consensus methods organizations that publish compendiums of
analytical methods for water, and equipment manufacturers, instrument
manufacturers and laboratories that modify compliance methods or seek
approval of new methods for compliance monitoring.

------------------------------------------------------------------------
             Category                  Examples of regulated entities
------------------------------------------------------------------------
Public............................  Government laboratories that develop
                                     analytical methods for compliance
                                     with the CWA and the SDWA.
Private...........................  Commercial laboratories, consensus
                                     methods organizations, instrument
                                     manufacturers, vendors, and other
                                     entities that develop or publish
                                     analytical methods for compliance
                                     with the CWA and the SDWA.
------------------------------------------------------------------------

    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 likely to be regulated by this action, you should
carefully read the applicability language of today's rule at
Secs. 136.4, 136.5 and 141.27. If you have questions regarding the
applicability of this action to a particular entity, consult the
individual listed in the preceding FOR FURTHER INFORMATION CONTACT
section.

Table of Contents

I. Authority
    A. Clean Water Act
    B. Safe Drinking Water Act
II. Background and History
    A. Introduction
    B. Current Office of Water Methods Approval Programs
    C. Streamlining Initiative
    D. Streamlining Objectives

[[Page 14977]]

    E. Public Meetings and Stakeholder Participation in Streamlining
Development
    F. Preamble Structure
III. Summary of Proposed Rule
    A. Method Flexibility
    1. Reference Method
    2. Method Modifications
    B. Quality Control
    1. Standardized Quality Control Elements
    2. Development of QC Acceptance Criteria
    C. Method Validation for Modified or New Methods
    1. Validation Study Plan
    2. Testing
    Table I. Summary of Validation Requirements for New Methods and
Method Modifications
    3. Validation Study Report
    4. Further Validation of a New Method
    5. Approval of a Screening Method as a New Method
    D. Method Review and Approval
    Table II. EPA Review and Action for New and Modified Methods
    1. Review and Approval of New Methods
    2. Review and Approval of Modified Methods
    3. Submission Package
    4. Regulatory Assistance Provided by Submitter
    5. EPA Review of Submission Package
    6. Proposal of Methods
    E. Other Issues
    1. Legal Impacts
    2. Method-defined Analytes
    3. Biological Methods
    4. Proprietary Reagents, Instruments, and Methods
    5. Restrictions by Consensus Standards Organizations
    6. Standard Data Format
    7. Withdrawal of Outdated Methods
    8. Administrative Record: Organic Methods, Streamlining Guide,
and Method Guidelines and Format
    9. Coordination with Other Federal Register Proposals
IV. Regulatory Analysis
    A. Executive Order 12866
    B. Unfunded Mandates
    C. Regulatory Flexibility Act
    D. Paperwork Reduction Act
V. Request for Comments
    A. General
    B. Specific
VI. References

I. Authority

A. Clean Water Act

    The Clean Water Act (CWA) requires the U.S. Environmental
Protection Agency (EPA) Administrator to promulgate effluent
limitations guidelines for specified categories and classes of point
sources. Section 301 of CWA prohibits the discharge of any pollutant
into navigable waters unless the discharge complies with a National
Pollutant Discharge Elimination System (NPDES) permit issued under CWA
section 402. Section 307 requires the EPA Administrator to publish
regulations establishing pretreatment standards for introduction of
pollutants into publicly owned treatment works (POTWs). Section 401
requires State and Tribal certification of a federal license that may
result in any discharge into the navigable waters.
    Section 304(h) of CWA requires the EPA Administrator to promulgate
guidelines establishing test procedures for data gathering and for
monitoring compliance with published guidelines. EPA's promulgation of
analytical methods is authorized under this section of CWA, as well as
the general rulemaking authority in CWA section 501(a). The section
304(h) test procedures (analytical methods) are published or
incorporated by reference at 40 CFR part 136. They include Methods for
Chemical Analysis of Water and Wastes (MCAWW); the EPA 200-, 600-, and
1600-series methods; methods published by consensus standards
organizations such as ASTM, AOAC-International, and Standard Methods
for the Examination of Water and Wastewater (Standard Methods)
published jointly by the American Public Health Association (APHA), the
American Water Works Association (AWWA), and the Water Environment
Federation (WEF); methods used by the U.S. Geological Survey; methods
developed by third parties; and other methods referenced in CWA
regulations. These methods support development of effluent limitations
guidelines and standards promulgated at 40 CFR parts 405-503, establish
compliance with NPDES permits issued under CWA section 402, allow
implementation of the pretreatment standards issued under CWA section
307, and apply to the certification of compliance with State water
quality standards under CWA section 401.

B. Safe Drinking Water Act

    The Safe Drinking Water Act (SDWA) requires the EPA Administrator
to promulgate national primary drinking water regulations (NPDWRs) that
specify maximum contaminant levels (MCLs) or treatment techniques for
listed drinking water contaminants (section 1412). Section 1445(a)
authorizes the Administrator to establish regulations for monitoring to
assist in determining whether persons comply with the requirements of
SDWA. EPA's promulgation of analytical methods is authorized under
these sections of SDWA, as well as the general rulemaking authority in
SDWA section 1450(a).
    SDWA section 1401(1)(D) specifies that NPDWRs contain criteria and
procedures to ensure a supply of drinking water that dependably
complies with MCLs, including quality control (QC) and testing
procedures to ensure compliance with such levels and to ensure proper
operation and maintenance of drinking water supply and distribution
systems. These test procedures are promulgated at 40 CFR part 141 and
include three MCAWW methods, the 200-, 300-, and 500-series EPA
methods, methods published by consensus standards organizations, and
other methods referenced in SDWA regulations. EPA uses these test
procedures to establish MCLs under SDWA section 1412 and to establish
monitoring requirements under SDWA section 1445(a).

II. Background and History

A. Introduction

    Within EPA, the Office of Water (OW) publishes analytical methods
for use in data gathering and environmental monitoring under the Clean
Water Act (CWA) and the Safe Drinking Water Act (SDWA). These methods
have been developed by EPA, by consensus standards organizations, and
by others. Many of these methods, especially those published before
1988, are prescriptive, with limited flexibility to change technologies
to respond to specific situations or to incorporate advances in
measurement technology. There has been a growing awareness, both within
EPA and in the analytical community, that the requirement to use
prescriptive measurement methods to comply with Agency regulations has
imposed an unintended regulatory burden and potentially created a
barrier to innovation in environmental monitoring.
    To reduce this regulatory burden and to lower the barriers to
innovation, the Agency in a future rulemaking may propose to adopt a
completely performance-based approach to environmental measurements. As
envisioned under such an approach, the Agency would specify the
question(s) to be answered by the measurement, the decision(s) to be
supported by the data, and the level of uncertainty that is acceptable.
EPA would specify performance criteria for the measurement and data
producers would be required to demonstrate that their proposed
measurement system (i.e., methods, sample handling procedures) meets
these specific performance criteria. Data producers would be required
to document performance and certify that they have used appropriate
quality assurance and QC procedures. The system would apply to
physical, chemical, and biological measurements

[[Page 14978]]

conducted either in laboratories or in the field (EPA 1996d).
    In a series of steps designed to adopt the performance-based
approach, each program office in the Agency has developed (or will
develop) an implementation plan that describes how the performance-
based approach would be put into practice. The Agency's goal is to have
these implementation plans as consistent as possible (i.e.,
``harmonized'') from program to program (EPA 1996e). The streamlining
initiative proposed in today's notice describes how EPA's Office of
Water is taking immediate steps to remove some of the regulatory
barriers to the use of new technologies for environmental measurements
of chemical analytes under the CWA and SDWA. This initiative would use
reference chemical methods that contain performance criteria and
methods that are already approved at 40 CFR parts 136 and 141. Other
implementation approaches to a performance-based measurement system,
such as listing in the CFR only the required performance criteria for
the measurement, are also possible; these approaches, which are not the
subject of today's proposal, may be the subject of future rulemakings.
    Today's rule proposes a process that would use standardized QC, QC
acceptance criteria, and method validation procedures for stakeholders
to gain approval of new and modified methods for compliance monitoring
under the SDWA and CWA. Today's rule also proposes to designate certain
approved drinking water and wastewater methods as reference methods.
The approved reference methods either presently contain QC acceptance
criteria, are supplemented with these criteria in today's proposal, or
would be supplemented with these criteria in a future rulemaking. In
subsequent rulemakings, EPA intends to extend the streamlined method
approval process to physical and biological (including microbiological)
measurements in the water programs.
    Through public meetings, announcements, and technical
presentations, EPA's Office of Water has coordinated this streamlining
initiative with various EPA Headquarters offices, EPA Regions, the
States, other governmental agencies, industry, consensus standards
organizations, environmental laboratories, and other interested
parties. With today's proposal, EPA attempts to define a comprehensive
program to increase analytical choices in selection of compliance
monitoring methods and to streamline the procedures for approval of
water methods. In this initiative, EPA seeks to promote rapid
introduction of innovative technologies, to encourage non-EPA
organizations to participate in the method development and approval
process, and to implement procedures to expedite the review and
approval of new and modified methods. Most importantly, EPA believes
that this initiative also offers the opportunity to improve the quality
of environmental monitoring.
    The proposed streamlined procedures for approval of water methods
would allow analysts to use professional judgement to modify and
develop alternatives to established Agency methods and to take
advantage of emerging technologies that reduce costs, overcome
analytical difficulties, and enhance data quality. The proposal to
increase the flexibility to modify reference methods would be governed
by QC acceptance criteria designed to ensure that the quality of the
environmental data would not be compromised. These criteria would be
used to demonstrate that a modified method produces results equal or
superior to results produced by the reference method. EPA also proposes
to require that all new methods contain such QC acceptance criteria so
that modifications could be made to new methods.
    EPA believes that allowing reference method modifications and
providing rapid approval of new methods would yield several benefits.
On behalf of regulated entities, analysts could select the analytical
method that yields the best performance in a specific situation. The QC
acceptance criteria in the reference method would enable the analyst to
document equivalent or superior performance to the satisfaction of
reviewing authorities. New technologies could be utilized to overcome
matrix interference problems, lower detection limits, improve
laboratory productivity, or reduce the amount of hazardous materials
used and hazardous wastes produced in the laboratory.
    A more flexible method approval program is consistent with the
Administration's Environmental Technology and Reinventing Government
initiatives and the National Technology Transfer and Advancement Act of
1995 (NTTAA). The proposed program would empower stakeholders while
decreasing demands on Agency resources and is intended to accelerate
environmental technological innovation while enhancing and maintaining
environmental protection. EPA believes that the incentives provided by
a more flexible water test methods approval program would spur the
development of new technologies and, with them, new jobs. EPA also
anticipates that the use of new technologies may lower the cost of
environmental measurements, thereby reducing costs of environmental
compliance for American industries and municipalities.

B. Current Office of Water Methods Approval Programs

    Requirements for approval of alternate analytical techniques
(methods) are specified at 40 CFR 136.4 and 136.5 for wastewater and at
40 CFR 141.27 for drinking water methods. These requirements are the
basis for the Agency's alternative test procedures (ATP) program for
water methods. Under the ATP program, persons may request approval to
modify steps in a reference method or approval to use a new method. The
person that submits the ATP application is responsible for validating
the new or modified method. Agency staff review the ATP validation
package and, if required, successful applications undergo formal
rulemaking. Rulemaking is required when a new or revised method is to
be added to the list of approved methods in the CFR. The ATP and
rulemaking processes make heavy demands on stakeholder, contractor,
EPA, and Office of Federal Register resources. The process can require
one to two years to gain approval of a method. Because advances in
analytical technology continue to outpace the capacity of OW's methods
approval program, the program is slow to respond to emerging
technologies and has been under-utilized. Under the streamlining
initiative described below, EPA proposes to increase method flexibility
by amending the procedures at 40 CFR 136.4, 136.5 and 141.27 to specify
a more rapid and less resource intensive process for approval of new
technologies.

C. Streamlining Initiative

    The proposed streamlining initiative is designed to improve overall
resource use while making the method development process more efficient
and accessible to non-EPA organizations. The goals of the initiative
are to decrease the need for developers of modified methods to use the
ATP program and to speed up the approval (or disapproval) of methods
subject to ATP review. EPA believes the streamlining initiative would
(1) encourage the use of emerging technologies by increasing the
flexibility to modify approved methods without formal EPA approval, (2)
provide a mechanism for non-EPA organizations to develop and submit new
methods for

[[Page 14979]]

approval, and (3) expedite the approval of new and modified methods by
improving the current ATP program. This initiative applies to approval
of wastewater and drinking water methods. Because of current emphases
on decreasing redundant activities, forming partnerships with
stakeholders, and more quickly adopting advances in technology, EPA
believes this is an appropriate time to look to organizations outside
of EPA for assistance in developing new methods that take advantage of
emerging technologies that reduce costs, overcome analytical
difficulties, and enhance data quality. Once the streamlining
initiative is in place, EPA expects to increase its reliance on outside
organizations as the developers of many new methods. EPA would focus
its method development activities on specialized or esoteric methods
needed to support regulation development or compliance monitoring.
    OW has coordinated the development of the streamlining initiative
with various governmental entities, industry, consensus standards
organizations, environmental laboratories, and other interested
parties. These organizations include the National Environmental
Laboratory Accreditation Committee (NELAC), and the Interagency
Steering Committee for Quality Assurance for Environmental
Measurements, which includes representatives from the Department of
Energy, Department of Defense, EPA, Air Force, U.S. Army Corps of
Engineers, U.S. Geological Survey (USGS), Bureau of Reclamation, and
other organizations.

D. Streamlining Objectives

    The purpose of the streamlining initiative is to implement a more
performance-based approach to environmental measurements under the SDWA
and CWA. The proposed streamlined methods approval procedures would
revolutionize the water methods approval program to expand the
flexibility to modify existing methods, provide a mechanism for non-EPA
organizations to gain approval of new methods, and expedite the
approval of new and modified methods. EPA has defined several specific
streamlining objectives:

     Increase the current flexibility to modify approved
chemical test procedures (methods) without formal EPA approval; this
would allow laboratories to overcome matrix interferences and would
facilitate early introduction of innovative technologies.
     Designate a reference method for each unique
combination of analyte and determinative technique and establish
standardized QC tests for approved methods to ensure data quality.
     Develop and publish QC acceptance criteria for any
reference method that does not have these criteria so that
laboratories can demonstrate equivalent or superior performance of a
modified method.
     Provide a standard method format and mechanism for
validation and approval of new methods to expedite method approval
and to increase confidence in the validity of the methods and
resulting data.
     Encourage stakeholder participation in method
development to keep pace with emerging technologies.
     Harmonize the wastewater and drinking water test
procedures to eliminate unnecessary inconsistencies.
     Increase standardized data reporting by recommending
use of standard data elements for reporting analytical results for
environmental and QC samples.
     Identify and propose withdrawal of outdated or obsolete
methods from 40 CFR parts 136 and 141 to modernize approved test
methods and to eliminate methods that are no longer published by the
issuing government agency, consensus methods organization, or
vendor.
     Work with the Office of Federal Register to incorporate
more methods by reference to reduce the volume of material published
in the CFR while ensuring and improving access to those methods by
all interested parties.

E. Public Meetings and Stakeholder Participation in Streamlining
Development

    EPA conducted four public meetings to develop a streamlined water
test methods approval program. EPA held the meetings in Seattle,
Washington, on September 28, 1995; in Boston, Massachusetts, on January
25, 1996; in Chicago, Illinois, on February 14, 1996; and in Denver,
Colorado, on July 24, 1996. The purpose of the meetings was to present
and discuss EPA's draft of the streamlining initiative and obtain
stakeholder advice for refining the streamlining approach prior to
proposal.
    All meetings were announced in the Federal Register in advance. The
first meeting, held in Seattle, was announced on September 12, 1995, in
a Federal Register notice titled, ``A Public Meeting and Availability
of Documents on Streamlining Approval of Analytical Methods at 40 CFR
part 136 and Flexibility in Existing Test Methods'' (60 FR 47325). This
Federal Register notice provided supplementary information regarding
the streamlining effort and made available several supporting
documents. Subsequent public meetings in Boston and Chicago were
announced on December 18, 1995 (60 FR 65207), and the fourth public
meeting in Denver was announced on July 10, 1996 (61 FR 36328). The
supporting documents and summaries of the four public meetings are in
the rule docket.
    In addition to the public meetings, EPA solicited support and
expertise from each of the consensus standards organizations and
government agencies that developed the methods already approved for use
under the wastewater and drinking water programs. These groups include
the American Public Health Association (APHA), American Water Works
Association (AWWA), and Water Environment Federation (WEF) as
publishers of Standard Methods for the Examination of Water and
Wastewater (Standard Methods); ASTM (formerly, American Society for
Testing and Materials); AOAC-International (formerly, the Association
of Official Analytical Chemists); and the USGS. EPA also provided the
opportunity for individuals, the regulated industry, the States, local
permitting authorities, vendors, laboratories, and laboratory
organizations such as the International Association of Environmental
Testing Laboratories (IAETL), to voice opinions at the meetings. The
groups offered valuable insight concerning problems with the current
program and recommended areas of improvement.
    Through the public meeting process and through individual meetings
with key stakeholder organizations, EPA received input from more than
400 stakeholders, including all major stakeholder organizations.
    Following the first three public meetings, EPA compiled and
reviewed preliminary stakeholder advice to assess the initial response
to streamlining and revise the approach accordingly. In response to
stakeholder suggestions, EPA made the following changes to the
streamlining initiative:

     Included drinking water methods (40 CFR part 141);
     Expanded flexibility to allow changes to the
determinative technique;
     Qualified flexibility to clarify that flexibility in
front-end techniques does not apply to sample collection and
preservation;
     Expanded Tier 1 validation to allow single-laboratory
application of a method modification to multiple matrix types;
     Added an option to have EPA review Tier 2 and Tier 3
method modifications upon request;
     Added an option to have EPA formally approve, upon
request, Tier 2 and Tier 3 method modifications through rulemaking;
and
     Added an option to submit screening methods to EPA for
approval.

    The Streamlining Guide (EPA 1996a) and Method Guidelines and Format
(EPA 1996c) served as the revised draft of the streamlining initiative
that was discussed at the final public meeting on streamlining held in
Denver. This

[[Page 14980]]

proposed rule incorporates suggestions received at the Denver public
meeting, at previous public meetings, by mail, by electronic mail, and
in informal discussions with and among EPA personnel, EPA contractors,
and stakeholders.
    Based upon the extensive involvement of internal and external
parties, and the generally favorable response, EPA anticipates that the
proposed regulations will be well received by regulatory authorities,
the regulated community, the technology development community, and the
laboratory service community.

F. Preamble Structure

    Section III of this preamble outlines the key elements of
streamlining. Section III.A describes EPA's proposal for increased
flexibility within the method approval program and increased
flexibility for modifications to existing methods. Section III.B
describes the standardized QC requirements and QC acceptance criteria
associated with implementation of flexibility. Section III.C describes
the requirements for validating new methods and method modifications,
using a system based on the intended application of the method or
modification. Section III.D describes the expedited method approval
process and includes procedures for submitting validated methods to EPA
for approval. Section III.E describes other issues associated with the
streamlining initiative. The descriptions in Section III delineate the
framework of EPA's method flexibility and methods approval streamlining
initiative. The Streamlining Guide (EPA 1996a) and other supporting
documents cited in this notice contain specifics about the start-up and
operation of the proposed streamlining initiative.

III. Summary of Proposed Rule

A. Method Flexibility

    In developing plans to improve the method approval program for
drinking water and wastewater methods, EPA concluded that the program's
success would depend largely on its ability to reflect the latest
advances in technology. This required, in turn, that the program be
efficient and flexible enough to encourage the development and use of
new measurement techniques. To meet these objectives, EPA determined
that the improved program would have two types of flexibility:
    (1) Flexibility to modify reference methods without seeking formal
approval through the regulatory process, and
    (2) Flexibility to develop and submit for approval entirely new
methods.
    The first type of flexibility is primarily an expansion of the
flexibility already provided in some approved water methods. Under the
streamlining program, it would no longer be necessary to apply for ATP
approval of a method modification, because an analyst would only need
to demonstrate and document that the modified method produces results
equal or superior to results produced by an EPA-designated reference
method. A designated reference method that contains QC acceptance
criteria against which performance of a method modification could be
measured would be the primary control to ensure data quality. Other
controls would include specific multi-laboratory and multi-matrix
requirements for validating modified methods and checklists for
documenting equivalency.
    The second type of flexibility would expand the ATP concept by
providing a mechanism whereby entirely new techniques would be
submitted to the Agency for approval, even when these techniques would
not serve as alternates to currently approved methods.
    In designing a framework through which this flexibility could be
implemented, EPA sought to balance the advantages of increased
flexibility against the concern that results produced by modifications
would be inferior to results produced by approved methods. To ensure
that these competing objectives could be met, EPA has devised a
framework that is based on:
    (1) Use of a standardized QC program with elements that could be
applied to all new and existing methods, and that is stringent enough
to meet compliance monitoring objectives, extensive enough to be
applied to a wide variety of analytical procedures, and yet simple
enough to avoid unwieldy or unnecessary restrictions;
    (2) Development and application of QC acceptance criteria for each
QC element against which method modifications could be assessed and
documented; and
    (3) Designation of a single reference method for each unique
combination of analyte and determinative technique. This reference
method would contain the QC acceptance criteria used to assess each QC
element for method equivalency.
    In today's proposed revisions to 40 CFR parts 136 and 141, EPA
would define the QC elements and associated acceptance criteria (e.g.,
calibration, sensitivity, accuracy, precision) necessary to demonstrate
the equivalency of a modified method to a reference method. These
proposed QC requirements are based on the three components outlined
above. Once equivalency was demonstrated, a modified method could be
used immediately without review by EPA because EPA would have
``preapproved'' the modified method.
    EPA believes that incorporating method flexibility into approved
analytical methods would improve laboratory operations by allowing
analysts to rely on professional judgement to ascertain the procedures
and protocols necessary to obtain the best results. Analysts could
employ new technologies to overcome matrix interferences, lower
detection limits, improve the reliability of results, reduce the
generation of hazardous wastes, improve laboratory productivity, and
reduce analytical costs.
1. Reference Method
    The foundation of the flexibility concept is the use of a reference
method. For each unique combination of analyte and determinative
technique, EPA has identified or would designate one approved method as
the reference method. If the performance of the modified method is
equal or superior to the performance of the reference method, the
method modification would be allowed. EPA believes that the use of a
reference method with defined QC acceptance criteria as the performance
measure provides a means for implementing the streamlining initiative.
This approach would clarify and reduce the effort required to
demonstrate the equivalency of method modifications.
    To implement the streamlining initiative, all reference methods
would need to specify standardized QC and QC acceptance criteria. The
QC and QC acceptance criteria would be necessary to demonstrate method
equivalency. Some methods, such as those approved at 40 CFR part 136,
Appendix A, already contain the necessary standardized QC and QC
acceptance criteria. Some other methods do not specifically identify
acceptance criteria for all of the standardized QC elements, but EPA
has the data from which such criteria could be developed. For this
proposed rule, selection of reference methods was based either on the
existence of QC acceptance criteria in the method or the availability
of data from which QC acceptance criteria could be developed. EPA is
proposing QC acceptance criteria for some inorganic analytes and
reference methods. These criteria are specified at 40 CFR 136.3 Table
IF and at 141.27(d) in the proposed rule text.

[[Page 14981]]

The remaining criteria for other analytes and reference methods would
be developed and proposed in subsequent rulemaking(s).
    For some determinative techniques, no currently approved method
contained either all of the QC acceptance criteria proposed in today's
rule (e.g., Table ID in 40 CFR part 136) or sufficient data from which
to develop such criteria. In these cases, no reference method has been
proposed; therefore, all of those methods would be classified as other
approved methods. Without a reference method, users would not be able
to implement the method flexibility proposed in this streamlining
initiative.
    EPA plans to include standardized QC with QC acceptance criteria in
all water methods under development and for all future water methods.
However, for drinking water methods, some of the QC acceptance criteria
(e.g., laboratory certification criteria) are currently (and may
continue to be) specified in drinking water regulations because these
criteria are an integral part of EPA's compliance monitoring
requirements.
    In the future, the selection of a new reference method would depend
upon requirements imposed by the submitting organization, the
availability of standardized QC and QC acceptance criteria in the
method, and the timing of the selection. EPA intends to rely on outside
organizations to develop the majority of the new methods. Therefore, it
is anticipated that new reference methods for a particular
determinative technique would be designated by being the first method
approved for the given combination of analyte and determinative
technique. To become a reference method, the new method would need to
contain standardized QC and QC acceptance criteria, and be approved
through an Agency rulemaking.
    The purpose of specifying a single reference method for a specific
combination of analyte and determinative technique is to avoid the
possible confusion that could be created if two or more reference
methods contained differing QC acceptance criteria. The QC acceptance
criteria associated with the single reference method would be the sole
criteria against which a method modification would be tested.
    In today's action, EPA proposes to retain all methods approved for
use at 40 CFR parts 136 or 141, but would re-categorize each of these
methods as either a ``reference method'' or an ``other approved
method.'' Both types of methods would carry equal regulatory status.
The difference between the methods would be that the reference method
would contain (or would be supplemented with) detailed QC acceptance
criteria that would need to be used to assess the equivalency of a
method modification.
2. Method Modifications
    Currently, explicit flexibility to modify a method is provided in
some of the approved 200-, 300-, 500-, 600-, and 1600-series methods
published by EPA. The allowed flexibility is typically specified
through use of the term ``should'' or the words ``or equivalent.''
Substitution of a 500-mL beaker for a 250-mL beaker or use of an
``equivalent'' chromatographic column are examples of such explicit
flexibility. The EPA 600- and 1600-series wastewater methods approved
at 40 CFR part 136, Appendix A, also provide limited flexibility to
improve separations and reduce the cost of measurements as long as
method performance is not sacrificed. As specified in those methods,
analysts who choose to exercise explicit flexibility are required to
meet the QC acceptance criteria of the approved method and to maintain
a record of the performance of the modified method for review at the
request of an auditor. In the development of more recent methods (e.g.,
Method 1664 and Method 1613), EPA expanded its definition of ``allowed
flexibility'' to further encourage use of new techniques that provide
equal or better performance at lower costs. However, no approved
methods provide unlimited flexibility and few provide the extensive
flexibility that EPA proposes in this initiative.
    The categories of method modifications considered in this proposal
are: (1) Sample collection and holding procedures, (2) front-end
techniques, (3) determinative techniques, and (4) analyte addition.
These categories are defined below and described in terms of present
and proposed flexibility to modify the procedures or techniques
included in each category.
    The first category, sample collection and holding procedures,
includes procedures and reagents used in the field, in transit, and at
the laboratory. This category includes sample containers, sample
holding times, preservation reagents and procedures, and shipping and
storage procedures and conditions. Currently, the Regional
Administrator may approve modifications to these procedures for
wastewater methods if the submitter so requests as specified at 40 CFR
136.3(c). In the drinking water program, except as explicitly allowed
in the compliance method, modifications of sample collection and
holding procedures would be approved through the ATP specification at
40 CFR 141.27.
    The flexibility proposed in today's rule would not extend to sample
collection or holding procedures. Upon implementation of streamlining,
modifications to sample collection and preservation conditions would
continue to require EPA approval as specified at 40 CFR 136.3(c) and
141.27(b). The latter section, 141.27(b), is a proposed amendment of 40
CFR 141.27 that was written to conform more closely with the
modification provisions at 40 CFR 136.3.
    Front-end techniques, the second category of method modifications,
are steps in the analytical process used at the laboratory that precede
the determinative technique and include all procedures, equipment,
solvents, etc., that are used to prepare a sample for analysis. The
third category is the determinative technique, which is defined as the
physical and/or chemical process by which an analyte is identified and
its concentration measured. For most methods, the determinative
technique consists of an instrumental measurement (e.g., a detector).
The fourth category covers increasing the analytical scope of a
reference method to include additional analytes.
    Historically, the wastewater program has allowed some changes to
front-end techniques, but only a few methods allow changes to the
determinative step. The drinking water program has allowed similar
changes provided the chemistry of the method is not changed. This means
that some modifications, such as changing the extraction solvent, are
not allowed in drinking water methods unless they receive formal EPA
approval.
    This proposed rule expands and more clearly defines proposed
modifications to approved methods. EPA proposes to allow the laboratory
analyst the flexibility to modify any and all front-end techniques,
provided the modification is not explicitly prohibited in the reference
method and provided the analyst demonstrates and documents that the
modification produces results equal or superior to results produced by
the reference method. The laboratory analyst would keep on file the
documents that demonstrate equivalency. Readers are referred to the
Streamlining Guide (EPA 1996a) for more guidance on this subject.
    EPA considered restricting the flexibility to change front-end
procedures, such as extraction solvents,

[[Page 14982]]

solvent-to-sample volumes, extraction media, and pH, because such
changes require a deeper understanding of the measurement science than
some users may have. However, EPA is not proposing to restrict front-
end flexibility because EPA believes it is appropriate to allow the
method development and auditing communities an opportunity to comment
on a far-reaching change to the current system. The developer of a
modified method always would have the option to ask EPA or another
regulatory authority for a technical opinion on the acceptability of
the validation data that supports the method. In the list of questions
at the end of this preamble, EPA invites public comment on what, if
any, additional QC would be needed to document the acceptability of
front-end modifications to a reference method.
    EPA proposes to allow use of an alternate determinative technique
that is not explicitly prohibited in the reference method, provided
that the analyst could demonstrate and document equivalency as outlined
above, and provided that four conditions could be met: (1) The
alternate determinative technique measures a property similar to the
prescribed technique, (2) the alternate technique is demonstrated to be
more specific (i.e., provides better separation of the analyte from
interferences) and/or more sensitive (i.e., produces a lower detection
limit) for the analyte of concern than the determinative technique in
the reference method, (3) there is not another approved method that
uses the alternate determinative technique for the determination of
that analyte, and (4) use of the alternate determinative technique
would not result in a nonsensical combination of analyte, front-end
technique, and determinative technique.
    Examples of allowed changes to a determinative technique would be
substitution of a photoionization detector for a flame ionization
detector for determination of polynuclear aromatic hydrocarbons,
substitution of a nitrogen-phosphorous detector for an electron capture
detector (ECD) for determination of analytes containing nitrogen or
phosphorous, and substitution of a fluorescence detector for an
ultraviolet or visible wavelength detector. Substitution of a mass
spectrometer (MS) for an ECD would not be allowed if there is an
approved MS method that measures the analyte of concern. Readers are
referred to the Streamlining Guide (EPA 1996a) for more guidance on
this subject.
    EPA proposes to limit changes to a determinative technique by the
four conditions described above to preclude nonsensical combinations of
analyte and determinative technique, to encourage a net benefit
(increased sensitivity and/or specificity), and to preclude multiple
reference methods with the same determinative technique but with
different QC acceptance criteria for the same analyte(s) of concern.
For example, if a mass spectrometer were substituted for the
conventional detectors in EPA methods 601-612, all of these methods
would become GC/MS methods, but all would contain different QC
acceptance criteria. Further, they would all conflict with approved GC/
MS Methods 625 and 1625. The proposed criteria for detector
substitution also would be consistent with EPA's decision in the
December 5, 1994, drinking water methods final rule (59 FR 62456) not
to allow substitution of MS in methods that specify conventional GC
detectors.
    Another reason for proposing to limit changes to the determinative
technique is that there are techniques, such as immunoassay, for which
EPA has no reference method and therefore no history to ensure that the
standardized QC proposed in today's rule would be germane to, or
adequate for, assurance of the quality of data produced by the novel
determinative technique. EPA would prefer that a new method be written
and submitted for approval when a novel determinative technique is
developed. EPA invites public comment on the suitability of the
conditions EPA proposes to place on the flexibility to modify
determinative techniques in EPA reference methods.
    In today's proposed rule, EPA also has specified how the analyst
would modify the analytical scope of a reference method to add
additional analytes. This option is proposed in response to public
comment on previous rules (59 FR 62456, December 5, 1994; 58 FR 65622,
December 15, 1993) to extend the scope of a reference method to the
determination of other analytes. Method developers seek this approval
when they want to adapt an existing method rather than develop a new
one to obtain occurrence data for a new analyte. EPA believes these
requests would have merit when there is a potential for new regulatory
requirements and historical monitoring data would be useful in making
process, treatment, or regulatory decisions. Examples of monitoring for
a new analyte would include industrial or POTW monitoring for ethers in
a discharge, public water system (PWS) monitoring for unregulated
pesticides or pesticide metabolites, and PWS monitoring for analytes on
the drinking water priority list. EPA also believes these requests
would have merit when technological advances would make the measurement
of additional analytes feasible (e.g., adding lead to the scope of EPA
Method 200.7). Under the proposed flexibility procedures for modified
and new methods, developers would obtain approval for the addition of
analytes to a reference method as an allowed method modification if the
conditions below would be met.
    An analyst may add a new target analyte to a reference method
provided (1) it could be demonstrated that the analyte would not
interfere with determination of the analytes of concern in that method,
(2) QC acceptance criteria were developed and employed for
determination of the target analyte, (3) there would not be another
approved method that uses the same determinative technique for that
analyte, and (4) that the reason for adding the analyte would not be to
avoid the sample preservation or sample (or extract) holding time
conditions that are already required for that analyte in another
approved method. The third and fourth criteria would preclude method
shopping whereby an analyst might add analytes to a reference method
with less rigid QC acceptance, sample collection or holding time
criteria. Under the criteria proposed above, if a reference method for
an analyte of concern required acidification of the sample, an analyst
would not have the flexibility to modify a method that does not require
sample acidification to include analysis of the analyte of concern.
Modifications of this type would require EPA approval as a new method.
    If QC acceptance criteria do not exist to allow addition of a new
analyte, the guidelines specified at 40 CFR part 136 Appendix E, at 40
CFR 136.4, 136.5 and 141.27 would be followed to develop and obtain
approval for these criteria. Alternatively, QC acceptance criteria for
the new analyte could be transferred from the criteria for an analyte
with similar chemical characteristics in the same method or from the
criteria for the analyte in another approved method. EPA provides
additional guidance on developing QC acceptance criteria in Chapter 3
of the Streamlining Guide (EPA 1996a).

B. Quality Control

    In order to establish that method modifications do not degrade
method performance, a standard would be required against which changes
could be compared. This standard would consist of standardized QC
elements and QC acceptance criteria that would be listed in the
reference method and/

[[Page 14983]]

 or in the regulations at 40 CFR parts 136 and 141. These criteria
would serve as definitive test criteria for evaluating the performance
of a method modification. As proposed, new methods would be required to
include QC acceptance criteria that were developed from a method
validation study according to procedures specified at 40 CFR 136.5,
141.27(c) and (e).
1. Standardized Quality Control Elements
    The standardized QC elements, described below, when paired with the
relevant QC acceptance criteria for each element, would allow analysts
to establish and document method performance. These elements would be
specified at 40 CFR part 136 Appendix E and at 40 CFR 136.4, 136.5 and
141.27. Additional guidance on procedures and requirements for these QC
elements are provided in the Streamlining Guide (EPA 1996a).

     Calibration--the process of establishing the
relationship between the concentration or amount of material
introduced into an instrument or measurement process and the output
signal.
     Calibration Verification--the means of establishing
that instrument performance remains within pre-established limits.
     Initial Precision and Recovery (IPR)--the mechanism to
demonstrate that a laboratory would produce reliable results with
the method prior to analysis of environmental samples. IPRs also
would demonstrate that a method modification produces results equal
or superior to those produced by a reference method.
     Ongoing Precision and Recovery--a process that
demonstrates that a laboratory is able to produce reliable results
continuously.
     Matrix Spike (MS)--a means to assess method performance
(especially analyte recovery) on a sample by adding a known amount
of the tested analyte.
     Matrix Spike Duplicate--a process to test the precision
of an analysis by repeating the MS test.
     Method Blank--a test that checks for laboratory
contamination.
     Method Detection Limit (MDL)--the MDL test, as
specified at Appendix B of 40 CFR part 136, is used to confirm that
a laboratory is capable of detecting an analyte of concern at the
level specified in the method or at an acceptable level for
regulatory compliance monitoring.
     Reference Sample--a test that serves as an external
check on method accuracy.
     Retention Time and Relative Retention Time Precision--a
means to assess the performance of a chromatographic separation
system; used to aid in the identification of each target analyte in
a complex mixture.
     Surrogate--a means to assess the performance of the
method within the given sample matrix by adding a known amount of a
different but chemically similar analyte. The results of these tests
would be used to assess method and laboratory performance.

    For each reference method, each QC test would have acceptance
criteria that define data acceptability.
2. Development of QC Acceptance Criteria
    QC acceptance criteria would be used to ensure that a modified
method produces results that are reliable, defensible and suitable for
regulatory decisions. QC acceptance criteria would be specified as
numeric limits. For example, the QC acceptance criteria for a MS/MSD
test may be 75-125 percent recovery with a relative percent difference
(RPD) of 20 or less. If these criteria were met for the MS/MSD test,
and all other QC acceptance criteria were met, results produced using
the modified method could be used for regulatory compliance purposes;
if not, corrective action would need to be taken and the sample
reanalyzed.
    Some methods currently approved at 40 CFR parts 136 and 141
explicitly specify QC acceptance criteria for all of the standardized
QC elements outlined in today's proposal, but many do not. In selecting
reference methods for today's proposal, EPA chose those methods that
contained QC acceptance criteria or data from which QC acceptance
criteria could be developed. For those methods that did not contain QC
acceptance criteria, QC acceptance criteria were developed from results
of single-laboratory or interlaboratory study data contained in the
method or from criteria contained in Appendix D of 40 CFR part 136.
These criteria are provided at 40 CFR 141.27(d) and 136.3 Table IF for
drinking water and wastewater reference methods, respectively. EPA
would develop QC acceptance criteria for certain approved methods that
do not presently contain these criteria. EPA would propose to designate
these approved methods as reference methods in a future rulemaking.

C. Method Validation for Modified or New Methods

    Method validation is the process by which an analyst or vendor
would establish the performance of a new method or would substantiate
the performance of a method modification to a reference method.
Validation would be necessary to demonstrate and document that the new
or modified method could yield reliable data for compliance monitoring
and other purposes. The party who developed the method or method
modification would be responsible for validating the method or method
modification.
    The requirements for validation would depend on the level of
intended use for the method modification or new method, and the
characteristics of the sample to which the method modification or new
method would be applied. Based on interactions with stakeholders, EPA
proposes to establish three levels of validation:

     Tier 1 methods would be used in a single laboratory in
a single matrix type from one industrial category or subcategory, or
in additional matrix types from any industrial category or
subcategory.
     Tier 2 methods would be used by all laboratories in one
or more matrix types within one industrial category or subcategory.
     Tier 3 methods would be used by all laboratories in
matrix types from all industrial categories or subcategories.

    Proposed definitions of the terms laboratory, matrix type, medium,
and tier are in the definitions sections at 40 CFR 136.2 and 141.2. In
the streamlining initiative, the term matrix type would be defined and
used to identify a sample medium with common characteristics across a
given industrial category or subcategory. The terms facility or system
would identify places where an industrial discharge activity occurs or
where a water source is treated and distributed as drinking (potable)
water. For example, all POTWs that comprise the municipal wastewater
treatment industry would be considered to be in one industrial
category. A typical municipal POTW has three matrix types: untreated
wastewater, treated wastewater, and sludge. All PWSs that comprise the
drinking water industry would be considered to be in one industrial
category and to be one matrix type--potable water. Similar definitions
would apply to matrix types in other industrial categories and
subcategories. EPA invites public comment on these definitions and
seeks suggestions on additional terms or concepts for which the public
believes a regulatory definition would be useful in implementing and
administering EPA's methods approval system.
    Method validation would comprise three steps: (1) development of a
validation study plan, (2) testing, and (3) preparation of a validation
study report.
1. Validation Study Plan
    A validation study plan would be required for development of a new
method at any tier or for modification of a reference method at Tiers 2
and 3. The organization responsible for conducting the study would
prepare the validation study plan. Requirements for method validation
would be specified at 40 CFR 136.4, 136.5 and 141.27 and at 40 CFR part
136 Appendix E. Additional guidance on suggested validation study

[[Page 14984]]

plans is available in the Streamlining Guide (EPA 1996a).
    A validation study plan would not be required for Tier 1 method
modifications, because EPA would expect that single-laboratory use
modifications would be simple and straightforward, and that requiring a
validation study plan for single-laboratory modifications would impose
an unnecessary regulatory burden on small laboratories.
2. Testing
    The number of testing laboratories, matrices, and replicate QC
tests for the method validation would depend on the tier at which the
new or modified method would be validated, as indicated in Table I
below. The specific requirements and procedures for performing QC
validation testing are specified at 40 CFR 136.4, 136.5 and at 141.27;
additional guidance is available in the Streamlining Guide (EPA 1996a).
Table I, which is taken from 40 CFR 136.5(d), summarizes validation
requirements at each tier.

                                 Table I.--Summary of Validation Requirements for New Methods and Method Modifications 1
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                             Number of                            Number of analyses required
                                                              ------------------------------------------------------------------------------------------
                      Method application                                       Matrix    Facilities/  IPR-reagent   IPR-sample
                                                                   Labs        types         PWSs       water 2      matrix 3      MS/MSD      MDL \4\
--------------------------------------------------------------------------------------------------------------------------------------------------------
Tier 1-Single-lab WW/DW--First matrix type or first PWS......            1            1            1            4            4          5 2            7
WW--Each addt'l matrix type (8 max.) from any industrial
 category....................................................            1            1            1          6 0          6 0          5 2          6 0
DW--Each addt'l PWS (2 max.).................................            1            1            1          6 0          6 0      5 2 6 0
Tier 2-Multi-lab, single matrix type WW/DW--Each matrix type
 in a single industrial category.............................            3            1            3           12            0          7 6           21
Tier 3-Multi-lab, multiple matrix types WW only--All matrix
 types, all industrial categories............................          8 9            9            9           36            0         7 18           63
--------------------------------------------------------------------------------------------------------------------------------------------------------
1 Numbers of analyses in this table do not include background analyses or additional QC tests such as calibration, blanks, etc. Validation requirements
  are based on the intended application of the method. Method application would be designated by tier for wastewater (WW) and drinking water (DW)
  programs. Three would be the maximum number of public water systems (PWSs) that would be required to validate a new or modified drinking water method
  at Tier 1 or 2. Nine would be the maximum number of matrix types (or facilities) that would be required to validate a new or modified wastewater
  method at Tier 1 or 3; at Tier 2 the number would be three matrix types.
2 IPR reagent water analyses would be used to validate a method modification and to establish QC acceptance criteria for initial precision and recovery
  (IPR) and ongoing precision and recovery (OPR) for a new method. The required number of IPR analyses, except as noted under footnote 7, would be four
  times the number of laboratories required to validate a method modification or new method because each laboratory would perform a 4-replicate IPR
  test.
3 IPR sample matrix analyses would be used to establish QC acceptance criteria for matrix spike/matrix spike duplicate (MS/MSD) recovery and precision
  for a Tier 1 new method only. Would not be required for validation of Tier 2 or 3 new methods because this variability data would be obtained from MS/
  MSD tests. Would not be required for validation of a method modification because MS/MSD data from the reference method would be used.
4 A method detection limit (MDL) test would be performed in each laboratory using the new or modified method. 40 CFR part 136 Appendix B requires a
  minimum of seven analyses per laboratory to determine an MDL. Each lab involved in validation of a wastewater modification would demonstrate that the
  modified method would achieve the detection limits specified in the regulations at 40 CFR parts 136 and 141 and/or in chapter 6 of the Streamlining
  Guide (EPA 1996a).
5 MS/MSD analyses would be required only for a method modification because, for new methods, the MS/MSD QC acceptance criteria would be established by
  the 4-replicate sample matrix IPR test. For modified methods, the MS/MSD test would demonstrate that the reference method MS/MSD QC acceptance
  criteria have been met.
6 The MDL, reagent water IPR, and sample matrix IPR tests would not have to be repeated after the first matrix type, facility, or PWS was validated.
7 For validation of a new method, the MS/MSD analyses would establish QC acceptance criteria for MS/MSD recovery and precision. For validation of a
  method modification, the MS/MSD analyses would demonstrate that reference method MS/MSD recovery and precision have been met. The required number of
  MS/MSD analyses would be two times the number of facilities, PWSs or matrix types tested.
8 The number of laboratories and samples would vary if a conventional interlaboratory study is used.

    The tiered approach to validating new and modified methods would
accommodate variability in the analytical performance of a method that
can be attributed to the type of sample analyzed. This variability is
termed a matrix effect and can be observed in samples taken at
different locations in matrices of the same type (intramatrix) or in
samples from different locations and in different matrix types
(intermatrix). Under the streamlining initiative, each successive tier
addresses matrix effects to a greater degree through increasing levels
of sample matrix effect validation, broadly defined as a test of the
extent to which differences, if any, in method performance could be
attributed to variability between samples obtained from different
industrial matrices, facilities, or PWSs. Matrix effects would need to
be tested by the IPR sample matrix and MS/MSD analyses listed in Table
I. Intramatrix effects would need to be tested in water samples taken
from different PWSs or from different waste streams. Intermatrix
effects would need to be validated on a group of samples taken from
discharge samples collected from several different industrial
categories. In all cases, the laboratory would try to determine if the
measurement result for the target analyte using a new or modified
method differed from the result obtained in a reagent water matrix or
in a previously validated matrix type or PWS sample.
    As indicated in Table I, a Tier 1 new or modified method would be
validated in a single laboratory on one or more matrix types obtained
from one or more facilities, or on samples obtained from one or more
PWSs. Validation of additional facilities or PWSs would require
analysis of MS/MSD samples for each additional facility or PWS.
However, in response to stakeholder requests that there should be some
maximum number of single-laboratory validations after which further
validation would be unnecessary because sample matrix effects would
have been sufficiently addressed, EPA

[[Page 14985]]

added a provision for a maximum number of matrix type, facility or PWS
analyses for Tier 1 methods. For a wastewater method, the maximum
number of matrix types or facilities tested under Tier 1 would be nine,
each from a different industrial category or subcategory. For a
drinking water method, the maximum number of PWS samples tested under
Tier 1 would be three samples, each from a PWS with different water
quality characteristics. EPA proposes to require validation in three
rather than nine PWSs, because three is consistent with the validation
data in many EPA drinking water methods and because the variability in
drinking water samples (and therefore the probability of matrix
effects) is usually less in drinking water samples than in wastewater
samples.
    Tier 2 validation would be applicable to one or more matrix types
within a single industrial category or subcategory. Because Tier 2 new
and modified methods would apply to each matrix across all
laboratories, EPA developed Tier 2 validation requirements to
incorporate intramatrix variability. Tier 2 would require validation of
the method in drinking water samples obtained from three PWSs, or
wastewater samples of one or more matrix types obtained from three or
more facilities within a single industrial category or subcategory.
    Tier 3 validation would be applicable to all matrix types in all
industrial categories. Consequently, Tier 3 validation requirements
would include provisions to account for both intramatrix and
intermatrix variability. However, Tier 3 validation would not apply to
the drinking water program because the program regulates only one
matrix type, drinking (potable) water. The wastewater program regulates
several industrial categories, each of which may contain more than one
matrix type. Tier 3 would require validation of the method in
wastewater samples of up to nine matrix types obtained from nine
different facilities.
    For all multi-matrix tiers, it would be extremely important to
select suitable samples and matrix types for validation. The matrix
types, facilities, or PWSs selected for matrix effect validation would
need to have sufficiently different water quality characteristics so
that the matrix effects, if any, could be observed. Proposed criteria
for selecting matrix types, facilities, or PWSs from which to obtain
these samples is specified at 40 CFR 136.4(a)(2)(i) and 141.27(b)(iii).
Additional guidance on testing sample matrix effects is available in
the Streamlining Guide (EPA 1996a).
    EPA invites public comment on the number of tests, laboratories,
matrix types, facilities, and PWSs that EPA is proposing for validation
of Tier 1, 2, or 3 methods. EPA is specifically interested in
suggestions for adding, deleting, or modifying the tests listed in
Table I. Commenters should provide EPA with reasons for (and preferably
data to support) any suggested changes.
3. Validation Study Report
    A validation study report would be required for a new method or
method modification at all tiers to document successful validation. The
primary documents to be included in the report would be the Checklist
for Initial Demonstration of Method Performance, the Checklist for
Continuing Demonstration of Method Performance (collectively, the
``Checklists''), and a Certification Statement. The Checklists would
document that all requirements for establishing equivalency were met;
the certification statement would commit the persons involved in the
method development or modification effort to the statements made in the
Checklists and the supporting information provided. The proposed
Checklists would be specified at 40 CFR part 136 Appendix E. The
checklists also would be published in the Streamlining Guide (EPA
1996a) with additional guidance on how to complete a checklist for a
typical water method. This guidance would be provided to aid the method
modifier or developer in understanding the information and test data to
be provided. The Checklists and certification statement would be
required as part of the validation study report. For Tier 1 method
modifications, the Checklists and certification statement would
comprise the data validation report. For all tiers, each laboratory
involved in validation of a method modification would need to complete
the Checklists and Certification Statement. More extensive
documentation would be required for a modification at Tiers 2 and 3 and
for all new methods.
    The validation study report for Tiers 2 and 3 would need to specify
the following information, as appropriate, for validation of a new or
modified method:

     Narrative--includes (a) a description of the method
being validated and the matrices, matrix types, and media to which
the method is applicable; (b) an indication of whether the method is
a modification of an approved reference method or a new method; (c)
reason for and description of the modification, if applicable; and
(d) information on the organization responsible for developing the
new method or method modification.
     Analyte(s)--name and Chemical Abstracts Service (CAS)
Registry Number or an EPA Environmental Monitoring Methods Index
(EMMI) Number. If a CAS Registry Number has not been assigned, the
submitter should attempt to obtain a number from the CAS Registry.
If the CAS Registry will not assign a number, the submitter should
contact the AMS Director for assignment of an EMMI Number. A report
for a modified method should indicate whether the modification
includes all forms of the analyte(s) in the scope of the reference
method. The definition of AMS Director is at 40 CFR parts 136.2 and
141.2.
     Method or modified test procedure--prepared in a
standard format; modified test procedures would be prepared in the
format of the reference method.
     Methodology and procedures--indicates the tier level at
which the new or modified method was tested, describes the approach
used to implement the study, describes the procedures used to report
and validate the data, and identifies the problems encountered
during implementation of the study.
     Results--for modified methods, includes a summary of QC
results required by the reference method and corresponding QC
results obtained with the modified method.
     Conclusions--describes the conclusions and limitations
of the study.
     Discussion--critically examines the study results.

    The following items would need to be included in appendixes to the
validation study report:

     Calculations;
     Raw data to allow an independent reviewer to verify
each determination and calculation performed by the laboratory;
     For instruments involving data systems, raw data on
magnetic tape or disk (upon request only);
     Names, titles, addresses, and phone numbers of analysts
who performed analyses and QA Officer who verified analyses; and
     Completed Checklists and Certification Statement.

    The validation study report for a new or modified method would need
to be retained on file by the organization responsible for developing
or applying the modification, and by regulated entities whose samples
are tested with the method modification. The party responsible for
developing and submitting the new method also would need to maintain on
file the complete records of all validation study tests including the
study plan, all laboratory results, the validation study report,
completed Checklists and Certification Statement, and other information
that supports the new method or method modification. All records would
need to be made available for review upon request to an auditor,
permitting authority, or other regulatory authority. These records
would need to be submitted to EPA if the method

[[Page 14986]]

developer elected to request formal approval of a method modification
at Tier 2 or 3.
4. Further Validation of a New Method
    After completing a Tier 1, 2, or 3 validation study of a new
method, the organization responsible for developing the method would
need to document the study results in accordance with requirements
proposed at 40 CFR part 136 Appendixes E, F, and G and would need to
submit the results and the method to EPA for review and approval. If,
based on its review of the method, EPA concluded that the method was
not sufficiently rugged or reliable for its intended use, EPA would
require further method development and testing. The tests and studies
that would be performed would need to be determined on a case-by-case
basis as these situations arise and would depend on the analyte(s) and
the analytical system.
5. Approval of a Screening Method as a New Method
    Methods currently approved for compliance monitoring at 40 CFR
parts 136 and 141 are considered to be confirmatory methods if the
method is sufficiently selective and quantitative so that most positive
results do not have to be verified by analysis with another method. The
term ``confirmatory'' is used to distinguish these methods from
screening methods. When using a screening method, all positive results
should be verified by re-analysis with a confirmatory method because
screening methods can be less selective and/or quantitative and,
therefore, more subject to false positives or imprecise results than
confirmatory methods. Characteristics of screening methods are
described in more detail in Chapter 2 of the Streamlining Guide (EPA
1996a).
    EPA has been asked by many stakeholders to allow use of screening
methods for wastewater and drinking water analyses. Although screening
methods may be less selective and quantitative than confirmatory
methods, they also could be designed to serve meaningful uses under
those statutes. Screening methods could be especially useful when
measuring trends in the contamination of a water source or when
knowledge of the performance of a waste treatment process would be more
important than an exact knowledge of the absolute amount and identity
of the contaminant or pollutant.
    Historically, EPA has not considered screening methods for approval
at 40 CFR part 136 or part 141. Under the streamlining initiative, EPA
proposes to consider the approval of screening methods for compliance
monitoring under the Safe Drinking Water Act provided that: (1) the
method would meet all the requirements specified in the regulations at
40 CFR 141.27, (2) all positive sample results obtained with the method
would be confirmed and reported using an approved confirmatory method,
and (3) the probability of the method producing a false negative result
at concentrations of regulatory interest would be no more than one
percent (1%). EPA has not yet specified how it intends to implement the
use of screening methods under the SDWA; the term was only recently
added in the 1996 SDWA amendments. Under the Clean Water Act, EPA is
considering the appropriateness of screening methods for use in NPDES
permit applications and ambient water quality monitoring by States. EPA
proposes to publish a separate table at 40 CFR parts 136 and 141 to
list approved screening methods. The Agency invites comment on the
approval criteria for screening methods for the uses described in the
SDWA, as well as for NPDES permit applications and ambient water
quality monitoring.

D. Method Review and Approval

    Under this proposed rule, EPA expects to significantly reduce the
number of methods that would pass through the ATP review and rulemaking
processes. EPA has this expectation because, once implemented, the
streamlining initiative would make it easier for method modifications
to be judged as being ``within the flexibility allowed by the
streamlining initiative.'' Method modifications demonstrated and
documented to be within the flexibility allowed by the streamlining
initiative would be preapproved by EPA for use at the tier for which
the modification was validated. Stakeholder remarks suggest that most
laboratories and method development organizations would welcome and use
this allowed flexibility.
    Stakeholders also have asked EPA to approve more quickly revised
versions of approved methods that are periodically published by EPA,
consensus standards organizations, and other government agencies. In
the past, EPA approved these revisions through a formal proposal and
public comment process. Using the flexibility provisions of today's
rule, users would be able to use a revised version of a reference
method as soon as it is published, provided that the results produced
were demonstrated to meet the QC acceptance criteria of the reference
method. This benefit alone would relieve much stakeholder frustration,
decrease the Agency's rulemaking burden, and improve EPA's partnership
with other government agencies and consensus standards organizations.
    Table II summarizes EPA's review and rulemaking responsibilities
for new and modified methods by tier.

      Table II.--EPA Review and Action for New and Modified Methods
------------------------------------------------------------------------
                                      New Method        Modified Method
------------------------------------------------------------------------
Tier 1, Single-lab..............  EPA review          No EPA review.
                                   required; EPA
                                   issues a letter
                                   of approval.
Tier 2, Multi-lab, single matrix  EPA review          If requested, EPA
 type.                             required;           reviews and
                                   approved through   --issues letter of
                                   rulemaking.         approval, or
                                                      --conducts
                                                       rulemaking.
Tier 3, Multi-lab, multiple       EPA review          If requested, EPA
 matrix types.                     required;           reviews and
                                   approved through   --issues letter of
                                   rulemaking.         approval, or
                                                      --conducts
                                                       rulemaking.
------------------------------------------------------------------------

1. Review and Approval of New Methods
    Currently, all new methods must be approved by EPA through
``formal'' EPA approval including rulemaking and publication at 40 CFR
part 136 or 141 before use. In today's rule, EPA proposes to grant
letter approvals of new methods that would be submitted under Tier 1
(i.e., single-laboratory, limited-use methods). New methods developed
for use under Tiers 2 or 3 would still require rulemaking. The purpose
for not requiring formal rulemaking at Tier 1 would be to

[[Page 14987]]

provide the means by which (1) a new technology could be introduced,
(2) confidentiality of a new technology could be maintained if desired
by the user of the new method, and (3) specific matrix interference
problems could be overcome. Allowing use of Tier 1 new methods would
enable multiple single laboratories to use a new technology until a
sufficient number of devices were available for interlaboratory
validation as a Tier 2 or 3 new method.
    EPA recognizes that allowing single-laboratory use of a new
technology for regulatory compliance carries with it the risk that
results produced with the new technology may not agree with results
produced by a reference method. However, EPA believes that sufficient
controls would be included in the streamlining program to ensure data
quality. EPA also believes that there would be a net benefit to the
regulated community by allowing new technologies that overcome matrix
interference problems. EPA solicits comment on this aspect of
streamlining, and is particularly interested in alternative ways EPA
might allow introduction of new technologies without rulemaking.
2. Review and Approval of Modified Methods
    Under the streamlining initiative proposed in today's rule, method
modifications would not require formal EPA approval; they would be
preapproved provided the analyst demonstrates and documents equivalency
with or superiority to the reference method QC criteria. Although
formal approval of a modification would not be required under the
streamlining initiative, several stakeholders have commented that, in
practice, use of a method modification would require the consent of the
regulated entity and responsible regulatory authority. These
stakeholders also expressed concern that without formal EPA approval,
obtaining consent from the regulated entity and/or regulatory authority
would be difficult. In response to these comments, EPA proposes to
allow, but not require, laboratories, industry associations, consensus
standards organizations, instrument manufacturers, and others to submit
Tier 2 or Tier 3 method modifications for EPA review with the
anticipation of a letter from EPA documenting approval. Also, for those
seeking public recognition that their Tier 2 or 3 method modifications
have been demonstrated to be acceptable for use, EPA proposes to work
with the organization to approve the method at 40 CFR part 136 or 141.
EPA would not review, provide letters of approval, or conduct formal
rulemaking for Tier 1 method modifications.
    EPA recognizes that preapproving method modifications poses
additional burdens for regulatory authorities, who may need to assess
the reasonableness and effectiveness of each modification. EPA
believes, however, that the Checklists, certification statement, and
accompanying instructions, which are proposed at 40 CFR part 136
Appendix E, and the validation report for the method modification,
which is proposed at 40 CFR part 136 Appendixes F and G, would provide
a regulatory authority the information necessary to make equivalency
assessments, and that this information would be presented in a
standardized and readily understandable format. To further assist
regulatory authorities in implementing this initiative, EPA has
included detailed guidance on assessing method modifications for
equivalency. This guidance is provided in Chapter 6 and in the
appendixes of the Streamlining Guide (EPA 1996a).
3. Submission Package
    The items to be submitted to EPA for proposal of a new method at
Tier 2 or 3 would include the method validation study report, which
would include the method prepared in a standard format. If the
submitter requested formal rulemaking to propose the method for
publication in the CFR, information in a format suitable for inclusion
in a draft preamble would also be required. Additionally, the
submission packet would need to include all relevant supporting
documents.
    To preclude a proliferation of potentially confusing formats, a
method should be submitted in a standard format. EPA recommends and
specifies the format that would be specified at 40 CFR part 136
Appendix F. This format is also detailed in Method Guidelines and
Format (EPA 1996c). Appendix F describes all elements of the format
prescribed by EPA's Environmental Monitoring Management Council (EMMC).
An objective of the EMMC format is to standardize all Agency analytical
methods. A standardized format used by a government agency such as the
U.S. Geological Survey or from a consensus standards organization such
as Standard Methods, ASTM, or AOAC-International could be used, but EPA
recommends that these formats be reserved for those organizations to
avoid the possible confusion over authorship. EPA would not accept
methods in non-standard formats because of the confusion that could be
created by a proliferation of method formats.
    A new method would need to include the standardized QC elements and
QC acceptance criteria. The QC acceptance criteria would need to be
developed from data gathered in the method validation study. Chapter 3
of the Streamlining Guide (EPA 1996a) provides guidance on the detailed
technical requirements for developing criteria that meet the
requirements that would be specified at 40 CFR 136.4, 136.5 and 141.27
and at 40 CFR part 136 Appendix E.
4. Regulatory Assistance Provided by Submitter
    Using procedures that would be specified at 40 CFR part 136
Appendix G, EPA would ask method submitters to assist EPA by providing,
as part of the submission package for methods to be proposed in the
Federal Register, information that would facilitate EPA's drafting of a
proposed rule. EPA would also ask submitters to provide technical
assistance, when necessary, in responding to public comments on the
submitter's method. Other assistance could be requested by EPA. The
information should be submitted in a format corresponding to the
preamble drafting conventions specified by the Office of the Federal
Register. Citations of examples for preambles are given in 40 CFR part
136 Appendix G and in the Streamlining Guide (EPA 1996a). Instructions
for drafting documents for the Office of the Federal Register are given
in the Document Drafting Handbook, for sale by the Superintendent of
Documents, Mail Stop: SSOP, Washington, DC 20402-9328 (Document 1993
O--351-677 QL3).
5. EPA Review of Submission Package
    Upon receipt of a request for approval, EPA would first check the
submission packet for completeness. If all of the documentation was in
order, EPA would use an internal workgroup to assess the scientific
merit of the method or modification and to evaluate the validation
study for consistency and appropriateness. Should any problems be
identified, the workgroup would contact the submitter to resolve the
outstanding issues. If these issues could not be resolved, EPA would
take no further action on the submission. If all validation
requirements were met and the submission passed internal review, EPA
would either issue a letter of approval or begin the rulemaking
process. All method modifications are preapproved, but a submitter
would have the option to request an EPA letter of approval or to
request a formal rulemaking for Tier 2 and 3 method

[[Page 14988]]

modifications. All new methods would be subject to EPA review. For Tier
1 new methods, EPA would issue letter approvals; Tier 2 and 3 new
methods would require formal Agency rulemaking.
6. Proposal of Methods
    For rulemaking, EPA would prepare the proposed rule based on the
draft preamble provided by the submitter. EPA would add the appropriate
updates to CFR tables or language and submit the proposed rule to the
Office of the Federal Register for publication. The proposed rule would
request public comment and allow a specified comment period (typically
60 days after publication in the Federal Register). At the end of the
comment period, EPA would forward significant public comments, if any,
to the method submitter. The submitter would need to provide technical
assistance to EPA in drafting responses to the comments. If the
comments could not be adequately addressed, EPA would not take final
action to approve the method. If all comments are addressed, EPA (with
assistance from the submitter) would need to complete a response-to-
comments document and prepare a final rule to approve the proposed
method. The final rule would state the date that the rule becomes
effective, typically 30 days after rule publication. As of this
effective date, the method would be approved (promulgated) and the
appropriate tables in the CFR would be updated.
    To expedite approval of noncontroversial updates to methods, such
as revisions to the methods published by EPA, other government
organizations, and consensus standards organizations, EPA intends to
use ``direct final'' rulemaking. Direct final rules would be warranted
when the action would not be expected to elicit public comment to which
the Agency would normally respond (i.e., no adverse comment). In this
process, the final rule and the companion proposal would be published
simultaneously as a ``direct final rule'' in the Federal Register. In a
direct final rule, the proposed rule has a specific comment period and
the final rule has a later effective date. If no adverse public
comments are received during the comment period for the proposed rule,
the actions become effective on the effective date of the final rule.
If adverse comment is received, the companion final rule is withdrawn
and a second final rule that responds to the public comments is
prepared and published with a new effective date.

E. Other Issues

1. Legal Impacts
    Stakeholders expressed concern regarding potential conflicts
between regulators and regulated entities when using modified methods.
For example, there was widespread concern over a situation in which a
discharger used a modified method and demonstrated compliance with a
regulatory concentration limit while a regulatory authority used the
unmodified reference method and obtained results suggesting that the
discharger was out of compliance.
    Based on internal EPA discussions, it became apparent that the
streamlining initiative would work only if the modified method, once
demonstrated to be equivalent to the reference method, carried the same
legal force and effect as the reference method. Therefore, the
difference in results produced by the modified and unmodified methods
would be attributable not to the modification, but to differences in
results produced by two laboratories. This situation is no different
than the existing situation where two laboratories can produce
different results, one set of which is above and the other below, a
regulatory compliance limit. The legal resolution would therefore
remain the same as today--a decision would be made based on examination
of all the relevant data.
2. Method-Defined Analytes
    The method flexibility introduced in today's proposal does not
extend to methods in which some part of the method ``defines'' the
analyte of concern. This type of analyte is termed a method-defined
analyte. Because method-defined analytes do not have a specific, known
composition, the result of the analytical measurement depends totally
on how the measurement is made. Examples of method-defined analytes
include adsorbable organic halides, biochemical oxygen demand, total
organic carbon, and whole effluent toxicity. Changes to the front-end
steps or the determinative techniques in these methods have the
potential of changing the result produced. EPA believes, however, that
certain parts of procedures for method-defined analytes could be
modified without adversely affecting method performance.
3. Biological Methods
    EPA intends to expand method flexibility to include biological
methods, but not in today's proposal. Biological methods include both
the testing of an environmental sample for the presence of
microbiological material (e.g., bacteria, protozoa and viruses) and the
use of biological organisms to measure whole effluent toxicity (WET) of
an environmental sample. EPA believes that flexibility in testing for
biological material would be similar to the flexibility allowed in the
modification to chemical analytical methods. Both the front-end and
determinative techniques should be able to be modified when the
modifications produce equivalent or superior results. EPA has protocols
for some microbiological methods that are currently used in the ATP
program (EPA 1995a, b). In a future rulemaking, EPA may revise the
microbiology protocols to conform with streamlining and method
flexibility procedures. In keeping with Agency goals for a more
performance-based approach to all environmental measurements, EPA also
may develop and propose method flexibility and new method approval
procedures for biological methods and for microbiological parameters
not covered under current EPA protocols.
    For WET methods, both new and modified methods are possible. New
methods may involve the use of a different taxonomic category other
than those currently listed at 40 CFR part 136. Method modifications
may be defined as the variation of one of the established summary test
conditions of the method, such as temperature or salinity. Method
modifications to the summary test conditions would not change the
acceptance criteria (e.g., control survival) which serve to identify
the standards of comparison of the ``reference method.'' EPA has not
sufficiently explored this issue to propose the specific requirements
to allow flexibility in all approved biological methods. Until EPA can
clarify the extent of acceptable flexibility, requests for changes in
biological methods would be reviewed and approved on an individual
basis.
4. Proprietary Reagents, Instruments, and Methods
    Stakeholders expressed concern over the role of proprietary
components in the streamlined water method approval process. EPA
separates proprietary components into three categories: proprietary
reagents, proprietary instruments, and proprietary methods. EPA intends
to attempt to accommodate the inclusion of proprietary reagents and
instruments in the approval of analytic methods for compliance purposes
to the extent that such inclusion still provides an adequate
opportunity for public review and comment under the Administrative
Procedure Act. EPA does not anticipate,

[[Page 14989]]

however, that it could approve the use of proprietary methods for
determining compliance with regulatory requirements where the entire
method is claimed as ``confidential business information'' because the
opportunity for public review and comment might be restricted too
severely. If a proprietary method is patented, the method would be
considered for approval as a compliance method because the public would
be able to comment on the patented method. EPA believes the restriction
on approval of proprietary methods is not serious because reagents or
instruments, not complete methods, will continue to be the most common
proprietary components used in compliance methods.
    Proprietary reagents and instruments are currently included for use
in approved methods and would continue to be allowed in approved
methods. The details of the proprietary elements would need to be
disclosed to EPA, but would be withheld from the public if the person
requesting protection for the confidential business information (CBI)
demonstrates that the information is entitled to confidential treatment
under 40 CFR part 2. Examples of proprietary components may include
immunoassay reagents and antibodies and liquid phases in GC columns;
e.g., DB-1, SPB-octyl, Dexsil'', etc. A new or
modified method submitted for EPA approval would need to include
language stating that the proprietary reagent or instrument could be
replaced by an equivalent. Changes made to the method after EPA
approval would require the manufacturer to demonstrate, through
supporting documentation, that the new proprietary equipment,
substance, or reagent would produce results equal or superior to
results produced with the material originally tested and on which the
method approval is based. Additionally, EPA would not propose a method
containing a proprietary reagent without accurate, specific
instructions for handling the reagent and for safe disposal of each
spent proprietary reagent and/or reaction product. When a material
safety data sheet (MSDS) would need to accompany the proprietary
material, the MSDS would be the appropriate vehicle to provide these
instructions. Submission of a complete MSDS with a new method would
satisfy EPA's need for instructions for safe handling and disposal of
the reagent.
5. Restrictions by Consensus Standards Organizations
    As envisioned, this initiative allows modification to a reference
method, provided that the QC acceptance criteria are met. Many of the
methods approved at 40 CFR parts 136 and 141 were developed by
consensus standard organizations such as Standard Methods, ASTM, and
AOAC-International. EPA expects to rely on these and other consensus
standards organizations for future methods, as required by the National
Technology Transfer and Advancement Act of 1995 (NTTAA) and because of
limited Agency resources for method development.
    Consensus standards organizations have expressed concern that a
modification to their methods would constitute a violation of the
method being considered a ``standard.'' Standard Methods, ASTM, and
AOAC-International have declined to allow unlimited modification of
their approved methods and, therefore, their methods could not serve as
reference methods nor be modified under the procedures outlined in this
initiative, as can be seen in the proposed CFR tables. This restriction
would not greatly affect the streamlining initiative because an EPA
method exists that would be used as a reference method for nearly all
analytes, and because most methods from consensus standards
organizations have sufficient internal flexibility to meet the
objectives of streamlining or are updated frequently to reflect recent
advances in technologies.
6. Standard Data Format
    For this proposed rule, EPA would not establish a standard format
for the submission of analytical data because of the large variety of
formats currently in use. However, EPA strongly recommends the
Department of Energy's Environmental Management Electronic Data
Deliverable Master Specification (DEEMS) because it is comprehensive
and it would expedite processing of a submitter's request. DEEMS is a
list of data elements that laboratories should submit to document the
method modification process. A DEEMS data element dictionary is
provided in the Streamlining Guide (EPA 1996a).
7. Withdrawal of Outdated Methods
    EPA also is considering withdrawal of methods that the Agency
believes are obsolete or are no longer used. For example, 40 CFR part
136, Table ID, footnote 3, references methods published in 1978 that
include thin-layer chromatography (TLC) methods. Because gas
chromatography and high performance liquid chromatography methods
provide better monitoring data and are more cost effective, most, if
not all, laboratories no longer use TLC methods. The TLC methods were
proposed for withdrawal in a previous notice (60 FR 53988, October 18,
1995), and EPA believes there may be similar outdated methods. EPA is
conducting a careful examination of Tables IA through IE of 40 CFR part
136 and of the tables at 40 CFR part 141, for obsolete or outdated
methods, and intends to propose withdrawal of those methods for which
newer methods are available.
8. Administrative Record: Organic Methods, Streamlining Guide, and
Method Guidelines and Format
    EPA specifies several 600- and 1600-series analytical methods at 40
CFR part 136 Appendix A for analysis of organic chemicals. If the
Office of the Federal Register approves incorporation by reference of
the Appendix A methods, EPA will withdraw Appendix A and publish all of
these methods in the document Methods for Organic Chemical Analysis of
Municipal and Industrial Wastewater, December 1996, EPA-821-B-96-005,
NTIS PB97-125298, ERIC D-A44/D-A47 (Organic Methods, EPA 1996b). This
document is part of the administrative record for this proposed rule;
copies can be inspected or obtained from NTIS or other sources as
described in the ADDRESSES section above.
    EPA also has drafted two guidance documents that are an integral
part of the administrative record for this proposed rule. The first
document, Guide to Method Flexibility and Approval of EPA Water
Methods, December 1996 Draft, EPA-821-D-96-004, PB97-117766
(Streamlining Guide, EPA 1996a), provides detailed guidance on the
overall streamlining initiative. The second document, Guidelines and
Format for Methods to Be Proposed at 40 CFR Part 136 or Part 141, EPA-
821-B-96-003, PB96-210448, July 1996 (Method Guidelines and Format, EPA
1996c), specifies the content and format required for new methods
developed by outside organizations. These documents are readily and
widely available to the public through NTIS, online, and other sources
listed in the ADDRESSES section above.
    The Streamlining Guide (EPA 1996a) in particular was drafted to
help method developers use the procedures proposed in today's rule to
validate and obtain approval of new or modified methods. The guidance
was written for use by laboratory auditors, permittees, water
utilities, regulatory authorities,

[[Page 14990]]

purveyors of new technology, and analytical laboratory personnel. The
document is organized into seven chapters, some of which are procedural
and others are descriptive, as appropriate to the topic. Chapter 1
summarizes the proposed streamlining initiative. Chapter 2 describes
the proposed expanded method flexibility. Chapter 3 describes the
proposed standard quality control tests and useful statistical
procedures for developing QC acceptance criteria for new methods.
Chapter 4 describes the proposed tiered system for validating a new
method or a method modification. Chapter 5 describes the proposed
method approval process, a standard method format, and procedures for
submitting validated methods to EPA for approval. Chapter 6 provides
guidance for assessing the method equivalency. Chapter 7 describes
possible future plans to extend method flexibility to microbiological
and macrobiological methods.
    The Streamlining Guide (EPA 1996a) also includes eight appendixes.
Appendix A provides a list of acronyms and abbreviations. Appendix B
provides a glossary of terms used in the streamlining initiative.
Appendix C provides examples of currently allowed method modifications.
Appendix D contains a DEEMS data element dictionary, which is a
Department of Defense reporting format that EPA suggests would speed
review of method validation data. Appendix E provides the EMMC method
equivalency checklists and certification statement. Appendix F provides
an example of a completed Appendix E checklist. Appendix G contains
bibliographic references. Appendix H describes EPA derived the proposed
QC acceptance criteria for inorganic chemicals, which are proposed at
40 CFR 136.3 Table IF and 141.27(d)., were calculated.
    EPA proposes to make some of the information in the Streamlining
Guide (EPA 1996a) and Method Guidelines and Format (EPA 1996c) a
regulatory requirement. Specifically, EPA proposes to include much of
the information in Chapter 2 (Method Flexibility), Chapter 6 (Assessing
Method Equivalency), Chapter 5 (Method Approval Process) and Appendix E
(Equivalency Checklists) as a requirement for approval of drinking and
wastewater methods. EPA proposes to accomplish this by designating the
excerpts from Chapters 2, 5 and 6 as 40 CFR part 136 Appendix G and the
equivalency checklists in Appendix E as 40 CFR part 136 Appendix E.
Other provisions of the Streamlining Guide (EPA 1996a), including, but
not limited to, Table 4-2, definitions of standardized QC elements, QC
acceptance criteria for inorganic chemicals, would also be included at
40 CFR 136.2, 136.3 Table IF, 136.4, 136.5, 141.2, and 141.27. EPA
would also adopt most of the provisions in Method Guidelines and Format
(EPA 1996c) as Appendix F at 40 CFR part 136. EPA invites public
comment on these two guidance documents and solicits comments on
whether additional guidance in these documents should be a regulatory
requirement.
9. Coordination with Other Federal Register Proposals
    On October 18, 1995 (60 FR 53988), EPA proposed to amend the list
of approved methods at 40 CFR part 136 by adding new or revised methods
for certain metal and inorganic analytes and by adding method citations
to Table IB and amending the incorporation by reference section
accordingly. EPA also proposed to withdraw approval of certain outdated
or rarely used analytical methods, as well as certain methods that
require use of hazardous or toxic reagents. As of today, EPA has not
promulgated a final rule implementing the proposed actions.
    The methods proposed for withdrawal that relate to this
streamlining initiative are primarily the EPA 200-series flame atomic
absorption spectrophotometry (FLAA) methods. Although approval of the
EPA FLAA methods is proposed to be withdrawn, FLAA methods published by
ASTM, Standard Methods, AOAC-International, and USGS would remain
approved and would remain listed in 40 CFR 136.3, Table IB. Withdrawal
of approval of EPA FLAA methods would remove these methods as reference
methods and would remove the QC acceptance criteria associated with
these methods. The net impact would be that there would be no FLAA
method against which modifications would be made. EPA does not consider
this a serious limitation because four FLAA methods (ASTM, Standard
Methods, AOAC-International, and USGS) would remain approved for nearly
all metals and the flexibility afforded by these methods should
adequately cover method modifications.
    In 1997, EPA intends to amend the regulations at parts 136 and 141,
as appropriate, to update outdated versions of methods to versions
published in the 19th edition of Standard Methods (APHA 1995), the 1996
Annual Book of ASTM Standards, Vols. 11.01 and 11.02 (ASTM 1996), and
in EPA's August 1995 manual titled, Methods for the Determination of
Organic Compounds in Drinking Water--Supplement III (EPA 1995c). If and
when the provisions of today's rule are promulgated, EPA expects to be
able to list these 1995 and 1996 versions of the compliance methods as
approved methods in the tables listed at 40 CFR parts 136 and 141. If
inclusion of these more recent versions would provide a basis to change
any of the QC acceptance criteria for the reference methods, the public
would be notified and provided with the opportunity to comment on the
new criteria.
10. Laboratory Certification and Laboratory Auditing
    Broad requirements for States to have an approved laboratory
certification program for analysis of drinking water samples are
specified at 40 CFR 142.10(b)(3). EPA provides more specific help to
State certification officers through written and verbal guidance. To
improve the uniformity of these certification programs, some laboratory
certification officers, method developers, and vendors have asked EPA
to provide more specific regulatory requirements. Today's rule responds
to these requests by proposing standardized QC elements for all water
compliance methods at 40 CFR 136.2 and 141.2, and at Appendix G of 40
CFR part 136. To standardize and facilitate laboratory audits, EPA also
would recommend use of several detailed checklists for auditing both
modified and unmodified methods. These standardized checklists would be
specified at Appendix E of 40 CFR part 136. EPA understands that
increasing the analyst's current flexibility to modify steps in a
compliance method could make the conduct of laboratory audits more
difficult. However, EPA believes that the proposal to specify
standardized QC elements for all methods and to require that
laboratories use standardized checklists to document and check method
performance will ameliorate these potential problems. EPA invites
public comment and is especially interested in what additional action,
if any, the Agency should take to facilitate the auditing of water
laboratories.

IV. Regulatory Analysis

A. Executive Order 12866

    Under Executive Order 12866 [58 FR 51,735 (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

[[Page 14991]]

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 entitlements, 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.
    This regulation is not major because it is intended to reduce costs
through flexibility and innovation. Therefore, this regulation would
not result in a cost to the economy of $100 million or more; would not
result in a major increase in costs or prices for consumers or
individual industries; and would not have significant adverse effects
on competition, investment, innovation, or international trade.
    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. Unfunded Mandates

    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 of 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 a 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. EPA has further determined that this rule
contains no regulatory requirements that might significantly or
uniquely affect small governments. This rulemaking should have minimal
financial impact, if any, on the current regulatory burden imposed on
regulated entities and regulators because the rulemaking does not
establish any additional regulatory requirements. The proposed rule
simply provides the option to modify approved methods or propose new
methods, if desired. EPA believes that method modifications and new
methods would not be used if not cost effective. Thus, today's rule is
not subject to the requirements of sections 202, 203, and 205 of the
UMRA.

C. Regulatory Flexibility Act

    The Regulatory Flexibility Act, 5 U.S.C. 601 et seq., requires EPA
and other agencies to prepare a final regulatory flexibility analysis
for regulations that have a significant impact on a substantial number
of small entities. This regulatory action does not have any adverse
impact on either small or large entities. Therefore, a regulatory
flexibility analysis is not required. 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.

D. Paperwork Reduction Act

    The information collection requirements in this proposed rule will
be submitted for approval to the Office of Management and Budget (OMB)
under the Paperwork Reduction Act, 44 U.S.C. 3501 et seq. shortly. EPA
is preparing an information collection request (ICR) document for this
proposed rule and will solicit public comment on it prior to
promulgating a final regulation. Comments on the proposed rule,
preamble, and ICR will all be considered before a final rule is
promulgated. The information collection requirements in this proposal
are described in Parts III.A (Method Flexibility), III.B (Quality
Control), III.C (Method Validation), III.D (Method Review), and III.E.6
(Standard Data Format). The information collection requirements in this
proposal are specified in Appendix E (Equivalency Checklists), Appendix
F (Guidelines and Format for Methods) and Appendix G (Method
Flexibility, Equivalency, and Approval) of 40 CFR part 136 and at 40
CFR 136.3(d); 136.4 (b) and (c); 136.5 (a), (b), (c), and (d); and at
40 CFR 141.27 (a), (b), and (c).
    The information requirements are not effective until OMB approves
them. An Agency may not conduct or sponsor, and a person is not
required to respond to a collection of information unless it displays a
currently valid OMB control number. The OMB control numbers for EPA's
regulations are listed in 40 CFR part 9 and 48 CFR chapter 15.

V. Request for Comments

A. General

    EPA is interested in eliciting constructive comments that would
allow the Agency to incorporate flexibility into existing methods and
to streamline the proposal and promulgation of new methods at 40 CFR
parts 136 and 141. On the other hand, EPA is interested in compelling
reasons why such a program may not work, even with extensive built-in
controls to ensure that the results produced by modified or new
analytical methods are reliable. EPA looks forward to working with all
interested and concerned parties to produce an improved system for
methods approval under the water methods program.

B. Specific

    EPA is soliciting public comment on the following specific
questions and options that relate to technical and policy decisions
that EPA may need to make to implement the streamlining initiative.
    1. As described in this preamble and the Streamlining Guide (EPA
1996a), the streamlining initiative would use a performance-based
approach in which a reference method that contains or is supplemented
with QC acceptance criteria is the standard against which a method
modification would be tested to demonstrate equivalency. In contrast to
the proposed performance-based reference-method approach, another
performance-based approach would be to specify only the QC acceptance

[[Page 14992]]

criteria without the need for a reference method. Should EPA retain the
proposed reference method approach with QC acceptance criteria? Or
should EPA change to a QC acceptance criteria approach only?
    2. Regarding question number one above, for what analytes, methods
or monitoring situations, if any, do you believe EPA should allow use
of either the performance-based reference method approach or the QC
acceptance criteria only approach?
    3. It may not be appropriate to develop QC acceptance criteria to
allow modification of methods for ``method-defined parameters,'' such
as biochemical oxygen demand or total suspended solids. What chemical,
microbiological, or biological analytes or analytical procedures do you
believe might not be amenable to streamlining or method flexibility
procedures?
    4. Should EPA implement streamlining and method flexibility
procedures only for new regulatory actions? Should EPA apply these
procedures to existing regulatory requirements but only when these
requirements are updated for some other purpose? Or should EPA apply
these proposed procedures to existing regulations now?
    5. EPA has undertaken several pilot studies of new methods to test
the streamlined method approval process, and expects the pilots to be
completed prior to promulgation of a final rule. Should EPA conduct
more extensive pilot studies, e.g., several pilots at each tier, or
should the changeover take place as soon as possible? If a pilot or
phase-in approach is adopted, should EPA phase-in by analyte group
(e.g., VOCs, metals, pesticides)? Or by the technologies employed by
the reference method (electron capture, mass spectrometry)?
    6. Is the proposed flexibility to modify the front-end and
determinative steps in a reference method broad enough to be of value
to the methods development community? For what steps in a reference
method, if any, would you increase or decrease the flexibility to
modify a method? If method flexibility were broadened, what additional
standardized QC elements or checklist items should be added to ensure
and document acceptable performance of the modification?
    7. If you believe that the proposed flexibility is too broad for
some methods, would you prefer that EPA limit flexibility by revising
approved methods to indicate the steps that could or could not be
changed? If yes, for which steps in a method (e.g., extraction/
digestion, concentration, determinative) or for which types of method
(e.g., those with method-defined analytes) should changes be allowed or
prohibited? If possible, please cite methods listed in 40 CFR part 136
or 141 as examples.
    8. If method flexibility were implemented as proposed, are the
standardized QC elements (accuracy, precision, detection limit,
calibration, reference sample, matrix spikes, etc.) described in part
III.C of this proposal and in the Streamlining Guide (EPA 1996a)
adequate to validate the acceptability of a modification to a reference

are the QC elements too extensive? If yes, which QC elements should be
deleted? And why?
    9. There has been some concern about the effect that changes to the
chemistry of a method may have on a laboratory or method developer's
ability to validate the performance of a modified method using the
Checklists and other requirements in the Streamlining Guide (EPA
1996a). For example, what effect, if any, might changing the extraction
solvent have on extract holding times that would not be picked up by
the Checklists' criteria? What effect, if any, might use of a different
extraction technique or a different solvent-to-sample ratio have that
would not be picked up by the standardized QC? What, if any, QC
elements should be changed or added to mitigate these concerns?
    10. Once EPA adopts streamlining and method flexibility procedures,
should EPA continue to develop and publish new methods or should EPA
rely on the private sector and consensus standards organizations? In
addressing this question, please consider the effect on small
laboratories, PWSs, and POTWs, if EPA discontinued providing EPA
methods.
    11. EPA has determined that, for wastewater programs, a modified
method, once validated and documented in accordance with the details in
this proposal, would carry the same force and legal effect as a
reference method. Do stakeholders believe that a modified method should
have equal status with a reference method? Or should EPA require
different levels of documentation for data gathered with the modified
method? If a modified method had a different level of documentation,
would stakeholders accept that it has legal status equal to that of an
unmodified method?
    12. Should EPA change the QC acceptance criteria in a reference
method when a significant technological advance or some other factor
demonstrates that the criteria could be made more rigorous? In your
response, you may assume that changing the criteria would not adversely
decrease the number of qualified laboratories needed to conduct
compliance monitoring with the more rigorous method.
    13. EPA plans to implement streamlining and method flexibility for
water methods through informal gathering of public comment and through
rulemaking (Federal Register proposal, public comment, and final rule),
of which this proposal is a part. Are there additional measures needed
to ensure that all stakeholders would be aware of the initiative and,
if so, what additional steps should EPA take?
    14. Given that a laboratory would be able to modify a method
without prior EPA approval, how would current EPA and state laboratory
auditing and certification programs continue to ensure that the
regulated community is properly conducting monitoring activities and
documenting monitoring system performance? Should documentation be
retained at the testing laboratory? At the facility? Or should EPA
require that the data be submitted to EPA or other regulatory authority
with each data package that results from use of the modification?
    15. Adoption of streamlining and method flexibility procedures
would require a deeper understanding of the science behind measurement
methods. Consequently, ``first-line'' compliance and enforcement
efforts may require additional resources and training of auditors. What
training would EPA, the Regions, the States, laboratories, and the
regulated community need to employ to successfully implement
streamlining or method flexibility procedures? What courses could be
developed, and who should be responsible for their development?
    16. Under the streamlining initiative, requests for approval of new
methods (i.e., new technologies or determinative techniques) would be
submitted to EPA under a streamlined ATP-type program. Should EPA
process these requests in the order received or should EPA have the
discretion to accelerate review of methods that provide the most
benefit to the Agency's regulatory program and/or to the needs of the
regulated community?
    17. What additional steps, if any, should the Agency take to ensure
that the use of method flexibility does not compromise enforceability
of applicable statutes and regulatory requirements? Will additional
training be sufficient or will inspectors need additional
qualifications to be able to assess the

[[Page 14993]]

quality of CWA and SDWA compliance data produced by a modified or new
reference method? What resources would be required to mitigate concerns
about the need for appropriate training of inspectors?
    18. EPA proposes to define several administrative (e.g., Assistant
Administrator, AMS Director) and technical (e.g. screening method,
standardized quality control) terms in the definitions at 40 CFR 136.2
and 141.2 and invites public comment on these definitions. Should EPA
omit any of the proposed definitions to avoid unnecessary confusion or
restrictions? Are there additional terms or concepts for which a
regulatory definition would be useful in implementing and administering
EPA's proposed methods approval system?
    19. EPA invites public comment on the guidance contained in the
Streamlining Guide (EPA 1996a) and in Method Guidelines and Format (EPA
1996c). These documents, which are part of the administrative record
for this proposal, provide guidance on method flexibility and method
validation procedures under the proposed streamlining initiative. The
documents also provide examples of certification statements and
checklists that would satisfy EPA's proposed requirements for
documenting the performance and equivalency of a modified or new
method. Portions of these documents are proposed to be regulatory
requirements (for example, see the proposed Appendixes E, F, and G and
other amendments to 40 CFR parts 136 and 141). Which, if any, of the
proposed requirements should EPA remove from the regulations and only
keep as guidance?
    20. In future rulemakings, EPA may propose to make more of the
information in the two documents described above regulatory
requirements. EPA would accomplish this by amending the wastewater and
drinking water regulations or, with the approval of the Office of the
Federal Register, incorporate by reference all or parts of the
Streamlining Guide (EPA 1996a) and Method Guidelines and Format (EPA
1996c) into the CFR. What, if any, additional guidance from these
documents should EPA propose as a regulatory requirement?

VI. References

     APHA. 1995. Nineteenth edition of Standard Methods for
the Examination of Water and Wastewater, 1992, American Public
Health Association, 1015 Fifteenth Street NW, Washington, D.C.
20005.
     ASTM. 1996. Annual Book of ASTM Methods, 1996, Vol.
11.01 and 11.02, American Society for Testing and Materials, 101
Barr Harbor Drive, West Conshohocken, PA 19428.
     EPA. 1995a. Protocol for Alternate Test Procedures for
Coliform Bacteria in Compliance with Drinking Water Regulations:
Presence/Absence Liquid Culture Methods for Finished Waters, Ver.
1.2, December 1995, U.S. Environmental Protection Agency.
     EPA. 1995b. Protocol for Alternate Test Procedures for
Coliform Bacteria in Compliance with Drinking Water Regulations:
Presence/Absence Membrane Filter Methods for Finished Waters, Ver.
1.2, December 1995, U.S. Environmental Protection Agency.
     EPA. 1995c. Methods for the Determination of Organic
Compounds in Drinking Water--Supplement III, EPA-600/R-95-131,
August 1995, NTIS PB95-261616.
     EPA. 1996a. Guide to Method Flexibility and Approval of
EPA Water Methods, December 1996 Draft, EPA-821-D-96-004, NTIS PB97-
117766, ERIC D-A43/D-A46 (Streamlining Guide, EPA 1996a).
     EPA. 1996b. Methods for Organic Chemical Analysis of
Municipal and Industrial Wastewater, December 1996, EPA-821-B-96-
005, NTIS PB97-125298, ERIC D-A44/D-A47 (Organic Methods, EPA
1996b).
     EPA. 1996c. Guidelines and Format for Methods to Be
Proposed at 40 CFR Part 136 or Part 141, EPA-821-B-96-003, NTIS
PB96-210448, ERIC D-A42/D-A45, July 1996 (Method Guidelines and
Format, EPA 1996c).
     EPA. 1996d. Draft Memorandum from Assistant
Administrators, ``Implementation Plan for the Agency Performance-
Based Measurement System,'' October 25, 1996, U.S. Environmental
Protection Agency.
     EPA. 1996e. Memorandum from Robert Perciasepe,
``Agency-wide Adoption of the Performance-Based Measurement System
Approach,'' November 1, 1996, U.S. Environmental Protection Agency.

List of Subjects

40 CFR Part 136

    Environmental protection, Laboratories, Water pollution control,
Reporting and recordkeeping requirements.

40 CFR Part 141

    Environmental protection, Laboratories, Water supply, Reporting and
recordkeeping requirements.

    Dated: March 17, 1997.
Carol M. Browner,
Administrator.

    For the reasons set out in the preamble, title 40 of the Code of
Federal Regulations is proposed to be amended as set forth below:

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

    1. The authority for part 136 is proposed to be revised to read as
follows:

    Authority: Secs. 301, 304(h), 307, and 501(a), Pub. L. 95-217,
91 Stat. 1566, et seq. (33 U.S.C. 1251, et seq.).
* * * * *
    2. Section 136.2 is proposed to be revised to read as follows:

Sec. 136.2  Definitions.

    As used in this part, the term:
    Accuracy means the degree of agreement between an observed value
and an accepted reference value. Accuracy includes random error
(precision) and systematic error (bias) that are caused by sampling and
analysis.
    Act means the Clean Water Act.
    Administrator means the Administrator of the U.S. Environmental
Protection Agency (EPA).
    Analyte or Analyte of concern means a substance or property that is
to be measured by an analysis.
    Approved method means a testing procedure or analytical method
promulgated at this part or at 40 CFR parts 405 through 500.
    Assistant Administrator (AA) means the EPA Assistant Administrator
for Water.
    Calibration (CAL) means the process of establishing the
relationship between the concentration or amount of material introduced
into an instrument or measurement process and the output signal.
    Calibration linearity means the degree to which calibration points
lie along a straight line.
    Calibration verification means the means of establishing that
instrument performance remains within pre-established limits.
    Determinative technique means the process (physical or chemical or
both) to measure the identity and concentration of an analyte. In test
methods, the determinative technique follows the front-end techniques.
    Director means the Director of the State Agency authorized to carry
out an approved National Pollutant Discharge Elimination System Program
under section 402 of the Act.
    Front-end technique means any technique in the analytical process
that precedes the determinative technique, including all procedures,
equipment, solvents, etc. that are used in the laboratory in the
preparation and cleanup of a sample but this excludes conditions and/or
procedures for the collection, preservation, shipment and storage of
the sample.
    Initial precision and recovery test (IPR) means analysis of a
minimum of four spiked replicate reference matrix samples under the
same conditions as

[[Page 14994]]

will be used for analysis of environmental samples. The IPR is used to
demonstrate that a laboratory is able to produce reliable results with
the method prior to analysis of environmental samples.
    Interference means a positive or negative effect on a measurement
caused by a substance other than the analyte being determined.
    Matrix means the component or substrate that contains the target
analyte.
    Matrix spike (MS) means a sample prepared by adding a known
quantity of target analyte to a specified amount of a sample matrix for
which an independent estimate of target analyte concentration is
available.
    Matrix spike duplicate (MSD) means a duplicate of the matrix spike.
The MS/MSD are used in combination to test the precision of an
analysis.
    Matrix type means a sample medium with common characteristics
across a given industrial category or industrial subcategory. Examples
include: C-stage effluents from chlorine bleach mills in the Pulp,
Paper, and Paperboard industrial category; effluent from the continuous
casting subcategory of the Iron and Steel industrial category; publicly
owned treatment work (POTW) sludge; and in-process streams in the
Atlantic and Gulf Coast Hand-shucked Oyster Processing subcategory.
    Medium means the physical phase of a sample matrix. Air, water,
soil, sediment, rock, and sludge are sample media.
    Method means an orderly and systematic arrangement of procedures
and techniques for performing an analysis.
    Method blank (or blank) means a sample absent the analytes of
interest and interferences, which is processed through all steps of a
method simultaneously with and under the same conditions as samples
that may contain an analyte of interest.
    Method detection limit (MDL) means the minimum concentration of a
substance that can be measured and reported with 99% confidence that
the analyte concentration is greater than zero as determined by the
procedure set forth in appendix B of this part.
    Method Guidelines and Format means the procedures set forth in
appendix F of this part.
    Method modification means a change to a reference method. The
change may be to a front-end technique or to the determinative
technique.
    Method validation means a process by which a laboratory or vendor
establishes the performance of a new method or substantiates the
performance of a method modification.
    Minimum level (ML) means the lowest level at which an entire
analytical system gives a recognizable signal and acceptable
calibration point for an analyte. It is equivalent to the concentration
of the lowest calibration standard, assuming that all method-specified
sample weights, volumes, and clean-up procedures have been employed.
    National Pollutant Discharge Elimination System (NPDES) means the
national system for the issuance of permits under section 402 of the
Clean Water Act and includes any State or interstate program which has
been approved by the Administrator, in whole or in part, pursuant to
section 402 of the Clean Water Act.
    New method means a combination of analyte of concern and
determinative technique that is different from those in the approved
methods.
    Ongoing precision and recovery sample (OPR) means a spiked
reference matrix sample that is processed through all steps of a method
simultaneously with and under the same conditions as samples that may
contain an analyte of interest. Also called a laboratory control sample
(LCS), the OPR/LCS is used to demonstrate that a laboratory is able to
produce reliable results continuously.
    Organic Methods means the document titled: Methods for the
Determination of Organic Compounds in Drinking Water--Supplement III
(available from the National Technical Information Service (NTIS), U.S.
Department of Commerce, Springfield, Virginia, 22161, 703/487-4600, at
NTIS publication PB97-125298).
    Other approved method means a promulgated method that is not
designated as a reference method.
    Percent recovery means the recovery multiplied by one hundred.
    Person means an individual; corporation; company; association;
partnership; municipality; or State, Federal, or tribal agency.
    Precision means the degree to which a set of observations or
measurements of the same property, usually obtained under similar
conditions, conform. Precision is usually expressed as standard
deviation, variance, or range, in either absolute or relative terms.
    Preparation means processing performed on a sample prior to
analysis, including extraction, concentration, and cleanup.
    Procedure means a set of systematic instructions for performing an
activity.
    Promulgated method means a method that has been published or
incorporated by reference into 40 CFR parts 136 or 405 through 500.
    Quality assurance (QA) means an integrated system of activities
involving planning, quality control, quality assessment, reporting, and
quality improvement to ensure that a product or service meets defined
standards of quality with a stated level of confidence.
    Quality control (QC) means the overall system of technical
activities conducted to measure and control the quality of a product or
service so that it meets the needs of a user. The purpose of QC is to
provide quality that is satisfactory, adequate, dependable, and
economical.
    Quality control acceptance criteria (QC acceptance criteria) means
performance specifications developed from validation data and used to
control the limits within which an analytical method is operated.
    Recovery means the total amount of analyte found divided by the
amount of analyte added as a spike.
    Reference method means an approved method that is designated as a
standard to which a modified method can be compared. A reference method
includes standardized QC and QC acceptance criteria as well as sample
preparation, cleanup, and other procedures.
    Regional Administrator means an EPA Regional Administrator.
    Screening method means a method that employs a qualitative
determinative technique for an analyte of interest that is different
from the determinative techniques used in the approved methods for that
analyte. The screening method should produce a false negative
probability less than 1%.
    Selectivity means the capability of a method or instrument to
respond to an analyte in the presence of interferences.
    Sensitivity means the capability of a method or instrument to
differentiate between different amounts or concentrations of an
analyte.
    Spike means the process of adding a known amount of an analyte to a
sample to determine the recovery.
    Spike amount means a known quantity of analyte added to a sample
and used to determine the recovery of a method.
    Standard deviation means the measure of the dispersion of observed
values expressed as the positive square root of the sum of the squares
of the difference between the individual values of a set and the
arithmetic mean of the set, divided by one less than the number of
values in the set.
    Standardized quality control (standardized QC) means a uniform set
of performance testing procedures that ensure reliable results.
Depending on

[[Page 14995]]

the method, standardized QC procedures include, but are not limited to,
the following: calibration, calibration linearity, calibration
verification, absolute retention time, absolute and relative retention
time precision, initial precision and recovery, ongoing precision and
recovery (laboratory control sample), surrogate or labeled compound
recovery, analysis of blanks, matrix spike and matrix spike duplicate
recovery and precision, demonstration of method detection limit(s), and
analysis of a reference sample.
    Surrogate means a substance with properties that mimic the behavior
of an analyte, that is unlikely to be found in an environmental sample,
and that is added to the sample for quality control purposes.
    Tier 1 means the application of a new or modified method in a
single laboratory to one or more matrix types.
    Tier 2 means the application of a new or modified method by all
laboratories to one or more matrix types within a single industrial
category or subcategory.
    Tier 3 means the application of a new or modified method by all
laboratories to all matrix types in all industrial categories and
subcategories (nationwide use).
    3. Section 136.3 is proposed to be amended by revising the last two
sentences and Tables IB, IC, and ID in paragraph (a); by adding Table
IF in paragraph (a); by revising paragraphs (c) and (d); and by
removing paragraph (e) (Table II following paragraph (e) is unchanged)
to read as follows:

Sec. 136.3  Identification of test procedures.

* * * * *
    (a) * * *
    The discharge parameter values for which reports are required must
be determined by one of the standard analytical test procedures
incorporated by reference and described in Tables IA, IB, IC, ID, and
IE, or by any alternate test procedure which has been approved by the
Administrator or Assistant Administrator under the provisions of
paragraph (d) of this section and Secs. 136.4 and 136.5. Under
paragraphs (b), (c) of this section and 40 CFR 401.13 alternate test
procedures may be used when such other test procedures have been
previously approved by the Administrator, Assistant Administrator, or
Regional Administrator of the Region in which the discharge will occur,
and providing the Director of the State in which such discharge will
occur does not object to the use of such alternate test procedure.
Standardized QC and QC acceptance criteria for modifications of the
inorganic contaminant reference methods in Table IB are specified in
Table IF.
* * * * *

                                                  Table IB.--List of Approved Inorganic Test Procedures
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                        Other approved methods
                                  Reference  -----------------------------------------------------------------------------------------------------------
     Parameter/methodology        method 1,     Standard methods 18th
                                      35                Ed.39                    ASTM 39             USGS 2, 39       AOAC--Intl.39          Other
--------------------------------------------------------------------------------------------------------------------------------------------------------
1. Acidity, as CaCO3, mg/L:
    Electrometric endpoint or          305.1  2310 B(4a)                 D1067-92                .................  .................  .................
     phenolphthalein endpoint.
2. Alkalinity, as CaCO3, mg/L:
    Electrometric or                   310.1  2320 B                     D1067-92                I-1030-85          973.43 3           .................
     Colorimetric titration to         310.2                                                     I-2030-85
     pH 4.5, manual or
     automated.
3. Aluminum--Total,4 mg/L;
 Digestion 4 followed by:
    AA direct aspiration 36....        202.1  3111 D                     ......................  I-3051-85          .................  .................
    AA furnace.................        202.2  3113 B                     ......................  .................  .................  .................
    Inductively Coupled Plasma/      5 200.7  3120 B                     ......................  .................  .................  .................
     Atomic Emission
     Spectrometry (ICP/AES).36.
    Direct Current Plasma (DCP)  ...........  .........................  D4190-82(88)            .................  .................  AES0029 34
     36.
    Colorimetric (Eriochrome     ...........  3500-AI D                  ......................  .................  .................  .................
     cyanine R).
4. Ammonia (as N), mg/L:
    Manual, distillation (at pH        350.2  4500-NH3 B                 ......................  .................  973.49 3           .................
     9.5) 6 followed by:.
    Nesslerization.............        350.2  4500-NH3 C                 D1426-93(A)             I-3520-85          973.49 3           .................
    Titration..................        350.2  4500-NH3 E                 ......................  .................  .................  .................
    Electrode..................        350.3  4500-NH3 F or G            D1426-93(B)             .................  .................  .................
    Automated phenate..........        350.1  4500-NH3 H                 ......................  I-4523-85          .................  .................
    Automated electrode........  ...........  .........................  ......................  .................  .................  379-75WE 7
5. Antimony--Total,4 mg/L;
 Digestion 4 followed by:
    AA direct aspiration 36....        204.1  3111 B                     ......................  .................  .................  .................
    AA furnace.................        204.2  3113 B                     ......................  .................  .................  .................
    ICP/AES 36.................      5 200.7  3120 B                     ......................  .................  .................  .................
6. Arsenic--Total,4 mg/L:
    Digestion 4 followed by....        206.5  .........................  ......................  .................  .................  .................
    AA gaseous hydride.........        206.3  3114 B 4.d                 D2972-93(B)             I-3062-85          .................  .................
    AA furnace.................        206.2  3113 B                     D2972-93(C)             .................  .................  .................
    ICP/AES 36.................      5 200.7  3120 B                     ......................  .................  .................  .................
    Colorimetric (SDDC)........        206.4  3500-As C                  D2972-93(A)             I-3060-85          .................  .................
7. Barium--Total,4 mg/L;
 Digestion 4 followed by:
    AA direct aspiration 36....        208.1  3111 D                     ......................  I-3084-85          .................  .................
    AA furnace.................        208.2  3113 B                     D4382-91                .................  .................  .................
    ICP/AES 36 ................      5 200.7  3120 B                     ......................  .................  .................  .................
    DCP 36.....................  ...........  .........................  ......................  .................  .................  AES0029 34
8. Beryllium--Total,4 mg/L;
 Digestion 4 followed by:

[[Page 14996]]


    AA direct aspiration.......        210.1  3111 D                     D3645-93(88)(A)         I-3095-85          .................  .................
    AA furnace.................        210.2  3113 B                     D3645-93(88)(B)         .................  .................  .................
    ICP/AES....................      5 200.7  3120 B                     ......................  .................  .................  .................
    DCP........................  ...........  .........................  D4190-82(88)            .................  .................  AES0029 34
    Colorimetric (aluminon)....  ...........  3500-Be D                  ......................  .................  .................  .................
9. Biochemical oxygen demand
 (BOD5), mg/L:
    Dissolved Oxygen Depletion.        405.1  5210 B                     ......................  I-1578-78 8        973.44 3           p. 17 9
10. Boron 37--Total, mg/L:
    Colorimetric (curcumin)....        212.3  4500-B B                   ......................  I-3112-85          .................  .................
    ICP/AES....................      5 200.7  3120 B                     ......................  .................  .................  .................
    DCP........................  ...........  .........................  D4190-82(88)            .................  .................  AES0029 34
11. Bromide, mg/L:
    Titrimetric................        320.1  .........................  D1246-82(88)(C)         I-1125-85          .................  p. S44 10
12. Cadmium--Total,4 mg/L;
 Digestion 4 followed by:
    AA direct aspiration 36....        213.1  3111 B or C                D3557-90                I-3135-85 or       974.27 3           p. 37 9
                                                                           (A or B)              I-3136-85
    AA furnace.................        213.2  3113 B                     D3557-90(C)             .................  .................  .................
    ICP/AES 36.................       5200.7  3120 B                     ......................  I-1472-85          .................  .................
    DCP 36 ....................  ...........  .........................  D4190-82(88)            .................  .................  AES0029 34
    Voltametry 11..............  ...........  .........................  D3557-90(C)             .................  .................  .................
    Colorimetric (Dithizone)...  ...........  3500-Cd D                  ......................  .................  .................  .................
13. Calcium-Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration.......        215.1  3111B                      511-93(B)               I-3152-85          .................  .................
    ICP/AES....................    \5\ 200,7  3120 B                     ......................  .................  .................  .................
    DCP........................  ...........  .........................  ......................  .................  .................  AES0029 \34\
    Titrimetric (EDTA).........        215.2  3500-Ca D                  511-93(A)               .................  .................  .................
14. Carbonaceous biochemical
 oxygen demand (CBOD5), mg/
 L\12\:
    Dissolved Oxygen Depletion   ...........  5210B                      ......................  .................  .................  .................
     with nitrification
     inhibitor.
15. Chemical oxygen demand
 (COD), mg/L; Titrimetric
                                       410.1  5220 C                     D1252-88(A)             I-3560-85          973.46 \3\         p. 17 \9\
                                       410.2  .........................  ......................  I-3562-85          .................  .................
                                       410.3  .........................  ......................  .................  .................  .................
    Spectrophotometric, manual         410.4  5220 D                     D1252-88(B)             I-3561-85          .................  Notes 13 or 14
     or automated.
16. Chloride, mg/L:
    Titrimetric (silver          ...........  4500-Cl-B                  D512-89(B)              I-1183-85          .................
     nitrate).
    (Mercuric nitrate).........        325.3  4500-Cl-C                  D512-89(A)              I-1184-85          973.51 \3\
    Colorimetric, manual.......  ...........  .........................  ......................  I-1187-85          .................  .................
    Automated (Ferricyanide)...     325.1 or  4500-Cl-E                  ......................  I-2187-85          .................  .................
                                       325.2
17. Chlorine-Total residual, mg/
 L; Titrimetric:
    Amperometric direct........        330.1  4500-Cl D                  D1253-86(92)            .................  .................  .................
    Iodometric direct..........        330.3  4500-Cl B                  ......................  .................  .................  .................
    Back titration ether end-          330.2  4500-Cl C                  ......................  .................  .................  .................
     point \15\.
    DPD-FAS....................        330.4  4500-Cl F                  ......................  .................  .................  .................
    Spectrophotometric, DPD....        330.5  4500-Cl G                  ......................  .................  .................  .................
    or Electrode...............  ...........  .........................  ......................  .................  .................  Note 16
18. Chromium VI dissolved, mg/
 L; 0.45 micron filtration
 followed by:
    AA chelation-extraction....        218.4  3111 C                     ......................  I-1232-85          .................  .................
    Colorimetric                 ...........  3500-Cr D                  D1687-92(A)             I-1230-85          .................  .................
     (Diphenylcarbazide).
19. Chromium-Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration \36\..        218.1  3111 B                     D1687-92(B)             I-3236-85          974.27 \3\         .................
    AA chelation-extraction....        218.3  3111 C                     ......................  .................  .................  .................
    AA furnace.................        218.2  3113 B                     D1687-92(C)             .................  .................  .................
    ICP/AES \36\...............    \5\ 200.7  3120 B                     ......................  .................  .................  .................
    DCP \36\...................  ...........  .........................  D4190-82(88)            .................  .................  AES0029 \34\
    Colorimetric                 ...........  3500-Cr D                  ......................  .................  .................  .................
     (Diphenylcarbazide).

[[Page 14997]]


20. Cobalt-Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration.......        219.1  3111 B or C                D3558-90(A or B)        I-3239-85          .................  p. 37 \9\
    AA furnace.................        219.2  3113 B                     D3558-90(C)             .................  .................  .................
    ICP/AES....................    \5\ 200.7  3120B                      ......................  .................  .................  .................
    DCP........................  ...........  .........................  D4190-82(88)            .................  .................  AES0029 \34\
21. Color platinum cobalt units
 or dominant wavelength, hue,
 luminance purity:
    Colorimetric (ADMI)........        110.1  2120 E                     ......................  .................  .................  Note 18
    (Platinum cobalt)..........        110.2  2120 B                     ......................  I-1250-85          .................  .................
    Spectrophotometric.........        110.3  2120 C                     ......................  .................  .................  .................
22. Copper--Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration \36\..    \5\ 220.1  3111 B or C                D1688-90(A or B         I-3270-85 or I-    974.27 \3\         p. 37 \9\
                                                                                                  3271-85
    AA furnace.................        220.2  3113 B                     D1688-90(C)             .................  .................  .................
    ICP/AES \36\...............    \5\ 200.7  3120 B                     ......................  .................  .................  .................
    DCP \36\...................  ...........  .........................  D4190-82(88)            .................  .................  AES0029 \34\
    Colorimetric (Neocuproine).  ...........  3500-Cu D                  ......................  .................  .................  .................
    (Bicinchoninate)...........  ...........  Or E                       ......................  .................  .................  8506 \19\
23. Cyanide--Total, mg/L:
    Manual distillation with     ...........  4500-CN C                  D2036-91(A)             .................  .................  .................
     MgCl2 followed by.
    Titrimetric................  ...........  4500-CN D                  ......................  .................  .................  p. 22 \9\
    Spectrophotometric, manual.    \31\335.2  4500-CN E                  D2036-91(A)             I-3300-85          .................  .................
    Automated \20\.............    \31\335.3  .........................  ......................  .................  .................  .................
24. Cyanide amenable to
 chlorination, mg/L:
    Manual distillation with           335.1  4500-CN G                  D2036-91(B)             .................  .................  .................
     MgCl2 followed by
     titrimetric or
     Spectrophotometric.
25. Fluoride--Total, mg/L:
    Manual distillation \6\      ...........  4500-F B                   ......................  .................  .................  .................
     followed by.
    Electrode, manual..........        340.2  4500-F C                   D1179-93(B)             .................  .................  .................
    Automated..................  ...........  .........................  ......................  I-4327-85          .................  .................
    Colorimetric (SPADNS)......        340.1  4500-F D                   D1179-93(A)             .................  .................  .................
    Automated complexone.......        340.3  4500-F E                   ......................  .................  .................  .................
26. Gold--Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration.......        231.1  3111 B                     ......................  .................  .................  .................
    AA furnace.................        231.2  .........................  ......................  .................  .................  .................
    DCP........................  ...........  .........................  ......................  .................  .................  AES0029 \34\
27. Hardness--Total, as CaCO3,
 mg/L:
    Automated colorimetric.....        130.1  .........................  ......................  .................  .................  .................
    Titrimetric (EDTA), or Ca          130.2  2340 B or C                D1126-86(92)            I-1338-85          973.52B \3\        .................
     plus Mg as their
     carbonates, by inductively
     coupled plasma or AA
     direct aspiration. (See
     Parameters 13 and 33)..
28. Hydrogen ion (pH), pH
 units:
    Electrometric measurement..        150.1  4500-H+ B                  D1293-84(90)            I-1586-85          973.41 \3\
                                                                           (A or B)
    Automated electrode........  ...........  .........................  ......................  .................  .................  378-75WA \21\
29. Iridium--Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration.......        235.1  3111 B                     ......................  .................  .................  .................
    AA furnace.................        235.2  .........................  ......................  .................  .................  .................
30. Iron--Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration \36\..        236.1  3111 B or C                D1068-90                I-3381-85          974.27 \3\         .................
                                                                           (A or B)
    AA furnace.................        236.2  3113 B                     D1068-90(C)             .................  .................  .................
    ICP/AES \36\...............    \5\ 200.7  3120 B                     ......................  .................  .................  .................
    DCP \36\...................  ...........  .........................  D4190-82(88)            .................  .................  AES0029 \34\
    Colorimetric                 ...........  3500-Fe D                  D1068-90(C)             .................  .................  8008 \22\
     (Phenanthroline).
31. Kjeldahl Nitrogen--Total,
 (as N), mg/L:
    Digestion and distillation         351.3  4500-NH3 B or C            D3590-89(A)             .................  .................  .................
     followed by.
    Titration..................        351.3  4500-NH3 E                 D3590-89(A)             .................  973.48 \3\         .................
    Nesslerization.............        351.3  4500-NH3 C                 D3590-89(A)             .................  .................  .................

[[Page 14998]]


    Electrode..................        351.3  4500-NH3 F or G            ......................  .................  .................  .................
    Automated phenate                  351.1  .........................  ......................  I-4551-78 \8\      .................  .................
     colorimetric.
    Semi-automated block               351.2  .........................  D3590-89(B)             .................  .................  .................
     digestor colorimetric.
    Manual or block digestor           351.4  .........................  D3590-89(A)             .................  .................  .................
     Potentiometric.
32. Lead--Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration \36\..        239.1  3111 B or C                D3559-90                I-3399-85          974.27 \3\         .................
                                                                           (A or B)
    AA furnace.................        239.2  3113 B                     D3559-90(C)             .................  .................  .................
    ICP/AES \36\...............    \5\ 200.7  3120 B                     ......................  .................  .................  .................
    DCP \36\...................  ...........  .........................  D4190-82(88)            .................  .................  AES0029 \34\
    Voltametry \11\............  ...........  .........................  D3559-90(C)             .................  .................  .................
    Colorimetric (Dithizone)...  ...........  3500-Pb D                  ......................  .................  .................  .................
33. Magnesium--Total,\4\ mg/L;
Digestion \4\ followed by:
    AA direct aspiration.......        242.1  3111 B                     D511-93(B)              I-3447-85          974.27 \3\         .................
    ICP/AES....................    \5\ 200.7  3120 B                     ......................  .................  .................  .................
    DCP........................  ...........  .........................  ......................  .................  .................  AES0029 \34\
    Gravimetric................  ...........  3500-Mg D                  ......................  .................  .................  .................
34. Manganese--Total \4\, mg/L;
 Digestion \4\ followed by:
    AA direct aspiration \36\..        243.1  3111 B                     D858-90                 I-3454-85          974.27 \3\         .................
                                                                           (A or B)
    AA furnace.................        243.2  3113 B                     D858-90(C)              .................  .................  .................
    ICP/AES \36\...............        200.7  3120 B                     ......................  .................  .................  .................
    DCP \36\...................    \5\ 200.7  3120 B                     ......................  .................  .................  AES0029 \34\
    Colorimetric (Persulfate)..  ...........  3500-Mn D                  ......................  .................  920.203 \3\        .................
    (Periodate)................  ...........  .........................  ......................  .................  .................  8034 \23\
35. Mercury--Total\4\, mg/L:
    Cold vapor, manual.........        245.1  3112 B                     D3223-91                I-3462-85          977.22 \3\         .................
    Automated..................        245.2  .........................  ......................  .................  .................  .................
36. Molybdenum--Total \4\, mg/
 L; Digestion \4\ followed by:
    AA direct aspiration.......        246.1  3111 D                     ......................  I-3490-85          .................  .................
    AA furnace.................        246.2  3113 B                     ......................  .................  .................  .................
    ICP/AES....................    \5\ 200.7  3120 B                     ......................  .................  .................  .................
    DCP........................  ...........  .........................  ......................  .................  .................  AES0029 \34\
37. Nickel--Total \4\, mg/L;
 Digestion \4\ followed by:
    AA direct aspiration \36\..        249.1  3111 B or C                D1886-90                I-3499-85          .................  .................
                                                                           (A or B)
    AA furnace.................        249.2  3113 B                     D1886-90(C)             .................  .................  .................
    ICP/AES \36\...............    \5\ 200.7  3120 B                     ......................  .................  .................  .................
    DCP \36\...................  ...........  .........................  D4190-82(88)            .................  .................  AES0029 \34\
    Colorimetric (heptoxime)...  ...........  3500-Ni D                  ......................  .................  .................  .................
38. Nitrate (as N), mg/L:
    Colorimetric (Brucine              352.1  .........................  ......................  .................  973.50 \3\         419 D \17\, p. 28
     sulfate), or Nitrate-                                                                                                              \9\
     nitrite N minus Nitrite N
     (See parameters 39 and 40).
39. Nitrate-nitrite (as N), mg/
 L:
    Cadmium reduction, manual..        353.3  4500-NO3- E                D3867-90(B)             .................  .................  .................
    Automated..................        353.2  4500-NO3-F                 D3867-90(A)             I-4545-85          .................  .................
    Automated hydrazine........        353.1  4500-NO3-H                 ......................  .................  .................  .................
40. Nitrite (as N), mg/L;
 Spectrophotometric:
    Manual.....................        354.1  4500-NO2- B                ......................  .................  .................  8507 \25\
    Automated (Diazotization)..  ...........  .........................  ......................  I-4540-85          .................  .................
41. Oil and grease--Total
 recoverable, mg/L:
    Gravimetric (extraction)...        413.1  5520 B \38\                ......................  .................  .................  .................
42. Organic carbon--Total
 (TOC), mg/L:
    Combustion or oxidation....        415.1  5310 B, C, or D            D2579-93                .................  973.47 \3\         p. 14 \24\
                                                                           (A or B)
43. Organic nitrogen (as N), mg/
 L:
    Total Kjeldahl N (Parameter  ...........  .........................  ......................  .................  .................  .................
     31) minus ammonia N
     (Parameter 4)..
44. Orthophosphate (as P), mg/L
 Ascorbic acid method:
    Automated..................        365.1  4500-P F                   ......................  I-4601-85          973.56 \3\         .................

[[Page 14999]]


    Manual single reagent......        365.2  4500-P E                   D515-88(A)              .................  973.55 \3\         .................
    Manual two reagent.........        365.3  .........................  ......................  .................  .................  .................
45. Osmium--Total \4\, mg/L;
 Digestion\4\ followed by:
    AA direct aspiration.......        252.1  3111 D                     ......................  .................  .................  .................
    AA furnace.................        252.2  .........................  ......................  .................  .................  .................
46. Oxygen, dissolved, mg/L:
    Winkler (Azide                     360.2  4500-O C                   D888-92(A)              I-1575-78 \8\      973.45B \3\        .................
     modification).
    Electrode..................        360.1  4500-O G                   D888-92(B)              I-1576-78 \8\      .................  .................
47. Palladium--Total \4\, mg/L;
 Digestion \4\ followed by:
    AA direct aspiration.......        253.1  3111 B                     ......................  .................  .................  p. S27 \10\
    AA furnace.................        253.2  .........................  ......................  .................  .................  p. S28 \10\
    DCP........................  ...........  .........................  ......................  .................  .................  AES0029 \34\
48. Phenols, mg/L:
    Manual distillation 26.....        420.1  .........................  ......................  .................  .................  Note 27
    Followed by:
        Colorimetric (4AAP)            420.1  .........................  ......................  .................  .................  Note 27
         manual.
        Automated \19\.........        420.2
49. Phosphorus (elemental), mg/
 L:
    Gas-liquid chromatography..  ...........  .........................  ......................  .................  .................  Note 28
50. Phosphorus--Total, mg/L:
    Persulfate digestion               365.2  4500-P B,5                 ......................  .................  973.55 3           .................
     followed by.
    Manual.....................     365.2 or  4500-P E                   D515-88(A)              .................  .................  .................
                                       365.3
    Automated ascorbic acid            365.1  4500-P F                   ......................  I-4600-85          973.56 3           .................
     reduction.
    Semi-automated block               365.4  .........................  D515-88(B)              .................  .................  .................
     digestor.
51. Platinum--Total,4 mg/L;
 Digestion 4 followed by:
    AA direct aspiration.......        255.1  3111 B                     ......................  .................  .................  .................
    AA furnace.................        255.2  .........................  ......................  .................  .................  .................
    DCP........................  ...........  .........................  ......................  .................  .................  AES0029 34
52. Potassium--Total,4 mg/L;
 Digestion 4 followed by:
    AA direct aspiration.......        258.1  3111 B                     ......................  I-3630-85          973.53 3           .................
    ICP/AES....................      5 200.7  3120 B                     ......................  .................  .................  .................
    Flame photometric..........  ...........  3500-K D                   ......................  .................  .................  .................
    Colorimetric...............  ...........  .........................  ......................  .................  .................  317 B 17
53. Residue--Total, mg/L:
    Gravimetric, 103 deg.-105          160.3  2540 B                     ......................  I-3750-85          .................  .................
     deg..
54. Residue--filterable, mg/L:         160.1  .........................  ......................  .................  .................  .................
    Gravimetric, 180 deg.......  ...........  2540 C                     ......................  I-1750-85          .................  .................
55. Residue--nonfilterable
 (TSS), mg/L:
    Gravimetric, 103 deg.-105          160.2  2540 D                     ......................  I-3765-85          .................  .................
     deg. post washing of
     residue.
56. Residue--settleable, mg/L:
    Volumetric, (Imhoff cone),         160.5  2540 F                     ......................  .................  .................  .................
     or gravimetric.
57. Residue--Volatile, mg/L:
    Gravimetric, 550 deg.......        160.4  .........................  ......................  I-3753-85          .................  .................
58. Rhodium--Total 4 mg/L;
 Digestion 4 followed by:
    AA direct aspiration.......        265.1  3111 B                     ......................  .................  .................  .................
    AA furnace.................        265.2  .........................  ......................  .................  .................  .................
59. Ruthenium--Total 4 mg/L;
 Digestion 4 followed by:
    AA direct aspiration.......        267.1  3111 B                     ......................  .................  .................  .................
    AA furnace.................        267.2  .........................  ......................  .................  .................  .................
60. Selenium--Total 4 mg/L;
 Digestion 4 followed by:
    AA furnace.................        270.2  3113 B                     D3859-93(B)             .................  .................  .................
    ICP/AES 36.................      5 200.7  3120 B                     ......................  .................  .................  .................
    AA gaseous hydride.........  ...........  3114 B                     D3859-93(A)             I-3667-85          .................  .................
61. Silica 37--Dissolved, mg/L;
 0.45 micron filtration
 followed by:
    Colorimetric, manual.......        370.1  4500-Si D                  D859-88                 I-1700-85          .................  .................
    Automated (Molybdosilicate)  ...........  .........................  ......................  I-2700-85          .................  .................
    ICP........................      5 200.7  3120 B                     ......................  .................  .................  .................
62. Silver--Total 4, mg/L;
 Digestion 4, 29 followed by:

[[Page 15000]]


    AA direct aspiration.......        272.1  3111 B or C                ......................  I-3720-85          974.27 3           p. 37 9
    AA furnace.................        272.2  3113 B                     ......................  .................  .................  .................
    ICP/AES....................      5 200.7  3120 B                     ......................  .................  .................  .................
    DCP........................  ...........  .........................  ......................  .................  .................  AES0029 34
63. Sodium-Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration.......        273.1  3111 B                     ......................  I-3735-85          973.54 \3\         .................
    ICP/AES....................    \5\ 200.7  3120 B                     ......................  .................  .................  .................
    DCP........................  ...........  .........................  ......................  .................  .................  AES0029 \34\
    Flame photometric..........  ...........  3500 Na D                  ......................  .................  .................
64. Specific conductance,
 micromhos/cm at 25  deg.C:
    Wheatstone bridge..........        120.1  2510 B                     D1125-91(A)             I-1780-85          973.40 \3\
65. Sulfate (as SO4), mg/L:
    Automated colorimetric             375.1  .........................  ......................  .................  .................
     (barium chloranilate).
    Gravimetric................        375.3  4500-SO4-2C or D           ......................  .................  925.54 \3\         .................
    Turbidimetric..............        375.4  .........................  D516-90                 .................  .................  426C \30\
66. Sulfide (as S), mg/L:
    Titrimetric (iodine).......        376.1  4500-S-2E                  ......................  I-3840-85          .................  .................
    Colorimetric (methylene            376.2  4500-S-2D                  ......................  .................  .................  .................
     blue).
67. Sulfite (as SO3), mg/L:
    Titrimetric (iodine-iodate)  ...........  377.1                      4500-SO3-2B             .................  .................  .................
68. Surfactants, mg/L:
    Colorimetric (methylene            425.1  5540 C                     D2330-88                .................  .................  .................
     blue).
69. Temperature,  deg.C:
    Thermometric...............        170.1  2550 B                     ......................  .................  .................  Note 32
70. Thallium--Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration.......        279.1  3111 B                     ......................  .................  .................  .................
    AA furnace.................        279.2  .........................  ......................  .................  .................  .................
    ICP/AES....................    \5\ 200.7  3120 B                     ......................  .................  .................  .................
71. Tin--Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration.......        282.1  3111 B                     ......................  I-3850-78 \8\      .................  .................
    AA furnace.................        282.2  3113 B                     ......................  .................  .................  .................
    ICP/AES....................    \5\ 200.7  .........................  ......................  .................  .................
72. Titanium--Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration.......        283.1  3111 D                     ......................  .................  .................  .................
    AA furnace.................        283.2  .........................  ......................  .................  .................  .................
    DCP........................  ...........  .........................  ......................  .................  .................  AES0029 \34\
73. Turbidity, NTU:
    Nephelometric..............        180.1  2130 B                     D1889-88(A)             I-3860-85          .................  .................
74. Vanadium--Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration.......        286.1  3111 D                     ......................  .................  .................  .................
    AA furnace.................        286.2  .........................  D3373-93                .................  .................  .................
    ICP/AES....................    \5\ 200.7  3120 B                     ......................  .................  .................  .................
    DCP........................  ...........  .........................  D4190-82(88)            .................  .................  AES0029 \34\
    Colorimetric (Gallic acid).  ...........  3500-V D                   ......................  .................  .................  .................
75. Zinc--Total,\4\ mg/L;
 Digestion \4\ followed by:
    AA direct aspiration \36\..        289.1  3111 B or C                D1691-90(A or B)        I-3900-85          974.27 \3\         p. 37 \9\
    AA furnace.................        289.2  .........................  ......................  .................  .................  .................
    ICP/AES \36\...............    \5\ 200.7  3120 B                     ......................  .................  .................  .................
    DCP \36\...................  ...........  .........................  D4190-82(88)            .................  .................  AES00290 \34\
    Colorimetric (Dithizone)...  ...........  3500-Zn E                  ......................  .................  .................  .................
    (Zincon)...................  ...........  3500-Zn F                  ......................  .................  .................  8009 \33\
--------------------------------------------------------------------------------------------------------------------------------------------------------
Table IB notes:
\1\ ``Methods for Chemical Analysis of Water and Wastes'', Environmental Protection Agency, Environmental Monitoring Systems Laboratory-Cincinnati (EMSL-
  CI), EPA-600/4-79-020, Revised March 1983 and 1979 where applicable.
\2\ Fishman, M.J., et al. ``Methods for Analysis of Inorganic Substances in Water and Fluvial Sediments'', U.S. Department of the Interior, Techniques
  of Water--Resource Investigations of the U.S. Geological Survey, Denver, CO, Revised 1989, unless otherwise stated.
\3\ ``Official Methods of Analysis of the Association of Official Analytical Chemists'', methods manual, 15th ed. (1990).

[[Page 15001]]


\4\ For the determination of total metals the sample is not filtered before processing. A digestion procedure is required to solubilize suspended
  material and to destroy possible organic-metal complexes. Two digestion procedures are given in ``Methods for Chemical Analysis of Water and Wastes,
  1979 and 1983''. One (Section 4.1.3), is a vigorous digestion using nitric acid. A less vigorous digestion using nitric and hydrochloric acids
  (Section 4.1.4) is preferred; however, the analyst should be cautioned that this mild digestion may not suffice for all sample types. Particularly, if
  a colorimetric procedure is to be employed, it is necessary to ensure that all organo-metallic bonds be broken so that the metal is in a reactive
  state. In those situations, the vigorous digestion is to be preferred making certain that at no time does the sample go to dryness. Samples containing
  large amounts of organic materials may also benefit by this vigorous digestion, however, vigorous digestion with concentrated nitric acid will convert
  antimony and tin to insoluble oxides and render them unavailable for analysis. Use of ICP/AES as well as determinations for certain elements such as
  antimony, arsenic, the noble metals, mercury, selenium, silver, tin, and titanium require a modified sample digestion procedure and in all cases the
  method write-up should be consulted for specific instructions and/or cautions.

Note: If the digestion procedure for direct aspiration AA included in one of the other approved references is different than the above, the EPA
  procedure must be used.

Dissolved metals are defined as those constituents which will pass through a 0.45 micron membrane filter. Following filtration of the sample, the
  referenced procedure for total metals must be followed. Sample digestion of the filtrate for dissolved metals (or digestion of the original sample
  solution for total metals) may be omitted for AA (direct aspiration or graphite furnace) and ICP analyses, provided the sample solution to be analyzed
  meets the following criteria:
a. has a low COD (<20),
b. is visibly transparent with a turbidity measurement of 1 NTU or less,
c. is colorless with no perceptible odor, and
d. is of one liquid phase and free of particulate or suspended matter following acidification.
\5\ The full text of Method 200.7, ``Inductively Coupled Plasma Atomic Emission Spectrometric Method for Trace Element Analysis of Water and Wastes'',
  is given at Appendix C of this Part 136.
\6\ Manual distillation is not required if comparability data on representative effluent samples are on company file to show that this preliminary
  distillation step is not necessary: however, manual distillation will be required to resolve any controversies.
\7\ Ammonia, Automated Electrode Method, Industrial Method Number 379-75 WE, dated February 19, 1976, Bran & Luebbe (Technicon) Auto Analyzer II, Bran &
  Luebbe Analyzing Technologies, Inc., Elmsford, N.Y. 10523.
\8\ The approved method is that cited in ``Methods for Determination of Inorganic Substances in Water and Fluvial Sediments'', USGS TWRI, Book 5,
  Chapter A1 (1979).
\9\ American National Standard on Photographic Processing Effluents, Apr. 2, 1975. Available from ANSI, 1430 Broadway, New York, NY 10018.
\10\ ``Selected Analytical Methods Approved and Cited by the United States Environmental Protection Agency'', Supplement to the Fifteenth Edition of
  Standard Methods for the Examination of Water and Wastewater (1981).
\11\ The use of normal and differential pulse voltage ramps to increase sensitivity and resolution is acceptable.
\12\ Carbonaceous biochemical oxygen demand (CBOD5) must not be confused with the traditional BOD5 test which measures ``total BOD''. The addition of
  the nitrification inhibitor is not a procedural option, but must be included to report the CBOD5 parameter. A discharger whose permit requires
  reporting the traditional BOD5 may not use a nitrification inhibitor in the procedure for reporting the results. Only when a discharger's permit
  specifically states CBOD5 is required can the permittee report data using the nitrification inhibitor.
\13\ OIC Chemical Oxygen Demand Method, Oceanography International Corporation, 1978, 512 West Loop, P.O. Box 2980, College Station, TX 77840.
\14\ Chemical Oxygen Demand, Method 8000, Hach Handbook of Water Analysis, 1979, Hach Chemical Company, P.O. Box 389, Loveland, CO 80537.
\15\ The back titration method will be used to resolve controversy.
\16\ Orion Research Instruction Manual, Residual Chlorine Electrode Model 97-70, 1977, Orion Research Incorporated, 840 Memorial Drive, Cambridge, MA
  02138. The calibration graph for the Orion residual chlorine method must be derived using a reagent blank and three standard solutions, containing
  0.2, 1.0, and 5.0 mL 0.00281 N potassium iodate/100 mL solution, respectively.
\17\ The approved method is that cited in Standard Methods for the Examination of Water and Wastewater, 14th Edition, 1976.
\18\ National Council of the Paper Industry for Air and Stream Improvement, (Inc.) Technical Bulletin 253, December 1971.
\19\ Copper, Biocinchoinate Method, Method 8506, Hach Handbook of Water Analysis, 1979, Hach Chemical Company, P.O. Box 389, Loveland, CO 80537.
\20\ After the manual distillation is completed, the autoanalyzer manifolds in EPA Methods 335.3 (cyanide) or 420.2 (phenols) are simplified by
  connecting the re-sample line directly to the sampler. When using the manifold setup shown in Method 335.3, the buffer 6.2 should be replaced with the
  buffer 7.6 found in Method 335.2.
\21\ Hydrogen ion (pH) Automated Electrode Method, Industrial Method Number 378-75WA, October 1976, Bran & Luebbe (Technicon) Autoanalyzer II. Bran &
  Luebbe Analyzing Technologies, Inc., Elmsford, NY 10523.
\22\ Iron, 1,10-Phenanthroline Method, Method 8008, 1980, Hach Chemical Company, P.O. Box 389, Loveland, CO 80537.
\23\ Manganese, Periodate Oxidation Method, Method 8034, Hach Handbook of Wastewater Analysis, 1979, pages 2-113 and 2-117, Hach Chemical Company,
  Loveland, CO 80537.
\24\ Wershaw, R.L., et al, ``Methods for Analysis of Organic Substances in Water'', Techniques of Water-Resources Investigation of the U.S. Geological
  Survey, Book 5, Chapter A3, (1972 Revised 1987) p. 14.
\25\ Nitrogen, Nitrite, Method 8507, Hach Chemical Company, P.O. Box 389, Loveland, CO 80537.
\26\ Just prior to distillation, adjust the sulfuric-acid-preserved sample to pH 4 with 1+9 NaOH.
\27\ The approved method is cited in Standard Methods for the Examination of Water and Wastewater, 14th Edition. The colorimetric reaction is conducted
  at a pH of 10.00.2. The approved methods are given on pp. 576-81 of the 14th Edition: Method 510A for distillation, Method 510B for the
  manual colorimetric procedure, or Method 510C for the manual spectrophotometric procedure.
\28\ R.F. Addison and R.G. Ackman, ``Direct Determination of Elemental Phosphorus by Gas-Liquid Chromatography'', Journal of Chromatography, Vol. 47,
  No. 3, pp. 421-426, 1970.
\29\ Approved methods for the analysis of silver in industrial wastewaters at concentrations of 1 mg/L and above are inadequate where silver exists as
  an inorganic halide. Silver halides such as the bromide and chloride are relatively insoluble in reagents such as nitric acid but are readily soluble
  in an aqueous buffer of sodium thiosulfate and sodium hydroxide to pH of 12. Therefore, for levels of silver above 1 mg/L, 20 mL of sample should be
  diluted to 100 mL by adding 40 mL each of 2 M Na2S2O3 and NaOH. Standards should be prepared in the same manner. For levels of silver below 1 mg/L the
  approved method is satisfactory.
\30\ The approved method is that cited in Standard Methods for the Examination of Water and Wastewater, 15th Edition.
\31\ EPA Methods 335.2 and 335.3 require the NaOH absorber solution final concentration to be adjusted to 0.25 N before colorimetric determination of
  total cyanide.
\32\ Stevens, H.H., Ficke, J.F., and Smoot, G.F., ``Water Temperature--Influential Factors, Field Measurement and Data Presentation'', Techniques of
  Water-Resources Investigations of the U.S. Geological Survey, Book 1, Chapter D1, 1975.
\33\ Zinc, Zincon Method, Method 8009, Hach Handbook of Water Analysis, 1979, pages 2-231 and 2-333, Hach Chemical Company, Loveland, CO 80537.
\34\ ``Direct Current Plasma (DCP) Optical Emission Spectrometric Method for Trace Elemental Analysis of Water and Wastes, Method AES0029'', 1986--
  Revised 1991, Fison Instruments, Inc., 32 Commerce Center, Cherry Hill Drive, Danvers, MA 01923.
\35\ Precision and recovery statements for the atomic absorption direct aspiration and graphite furnace methods, and for the spectrophotometric SDDC
  method for arsenic are provided in Appendix D of this part titled, ``Precision and Recovery Statements for Methods for Measuring Metals''.
\36\ ``Closed Vessel Microwave Digestion of Wastewater Samples for Determination of Metals'', CEM Corporation, P.O. Box 200, Matthews, NC 28106-0200,
  April 16, 1992. Available from the CEM Corporation.
\37\ When determining boron and silica, only plastic, PTFE, or quartz sampling and laboratory ware may be used from time of collection until completion
  of analysis.

[[Page 15002]]


\38\ Only the trichlorofluoromethane extraction solvent is approved.
\39\ Methods published by this organization and approved for use under this part may not be modified beyond the modifications expressly allowed and
  defined in each method.

                 Table IC--List of Approved Test Procedures for Non-Pesticide Organic Compounds
----------------------------------------------------------------------------------------------------------------
                                                                     Other approved methods
                                    Reference  -----------------------------------------------------------------
    Parameter \1\/methodology      method \27\    Standard methods
                                                    18th Ed.\8\            ASTM \8\                Other
----------------------------------------------------------------------------------------------------------------
1. Acenaphthene:
    GC/FID.......................          610  6440 B               ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
    HPLC/UV......................          610  6440 B               D4657-92             ......................
2. Acenaphthylene:
    GC/FID.......................          610  6440 B               ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
    HPLC/UV......................          610  6440 B               D4657-92             ......................
3. Acrolein:
    GC/FID.......................          603  ...................  ...................  ......................
    GC/MS........................      \4\ 604  ...................  ...................  ......................
    GC/MS/Isotope................         1624  ...................  ...................  ......................
4. Acrylonitrile:
    GC/FID.......................          603  ...................  ...................  ......................
    GC/MS........................      \4\ 624  ...................  ...................  ......................
    GC/MS/Isotope................         1624  ...................  ...................  ......................
    HPLC/UV......................          610  ...................  ...................  ......................
5. Anthracene:
    GC/FID.......................          610  6440 B               ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
    HPLC/UV......................          610  6440 B               D4657-92             ......................
6. Benzene:
    GC/PID.......................          602  7220 B               ...................  ......................
    GC/MS........................          624  ...................  ...................  ......................
    GC/MS/Isotope................         1624  ...................  ...................  ......................
    HPLC/UV......................  ...........  ...................  ...................  ......................
7. Benzidine:                          Note 3,  ...................  p. 1.
    GC/MS........................      \5\ 625  ...................  ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
    HPLC/ELCD....................          605  ...................  ...................  ......................
8. Benzo(a)anthracene:
    GC/FID.......................          610  6440 B               ...................  ......................
    GC/MS........................          625  6440 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
    HPLC/UV......................          610  6440 B               D4657-92             ......................
9. Benzo(a)pyrene:
    GC/FID.......................          610  6410 B               ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
    HPLC/UV......................          610  6440 B               D4657-92             ......................
10. Benzo(b)fluoranthene:
    GC/FID.......................          610  6440 B               ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
    HPLC/UV......................          610  6440 B               D4657-92             ......................
11. Benzo(g, h, i)perylene:
    GC/FID.......................          610  6440 B               ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
    HPLC/UV......................          610  6440 B               D4657-92             ......................
12. Benzo(k)fluoranthene:
    GC/FID.......................          610  6440 B               ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
    HPLC/UV......................          610  6440 B               D4657-92             ......................
13. Benzyl chloride..............  ...........  ...................  ...................  Note 3, p. 130: Note
                                                                                           6, p. S102.
14. Benzyl butyl phthalate:
    GC/ECD.......................          606  ...................  ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................

[[Page 15003]]


15. Bis(2-chloroethoxy) methane:
    GC/ELCD......................          611  ...................  ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
16. Bis(2-chloroethyl) ether:
    GC/ELCD......................          611  ...................  ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
17. Bis (2-ethylhexyl) phthalate:
    GC/ECD.......................          606  6230 B               ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
18. Bromodichloromethane:
    GC/ELCD......................          601  6230 B               ...................  ......................
    GC/MS........................          624  6210 B               ...................  ......................
    GC/MS/Isotope................         1624  ...................  ...................  ......................
19. Bromoform:
    GC/ELCD......................          601  6230 B               ...................  ......................
    GC/MS........................          624  6210 B               ...................  ......................
    GC/MS/Isotope................         1624  ...................  ...................  ......................
20. Bromomethane:
    GC/ELCD......................          601  6230 B               ...................  ......................
    GC/MS........................          624  6410 B               ...................  ......................
    GC/MS/Isotope................         1624  ...................  ...................  ......................
21. 4-Bromophenylphenyl ether:
    GC/ELCD......................          611  ...................  ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
22. Carbon tetrachloride:              Note 3,  ...................  ...................  p. 130.
    GC/ELCD......................          601  6230 B               ...................  ......................
    GC/MS........................          624  6410 B               ...................  ......................
    GC/MS/Isotope................         1624  ...................  ...................  ......................
23. 4-Chloro-3-methylphenol:
    GC/FID.......................          604  6420 B               ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
24. Chlorobenzene:                     Note 3,  ...................  ...................  p. 130.
    GC/ELCD......................          601  6230 B               ...................  ......................
    GC/PID.......................          602  6220 B               ...................  ......................
    GC/MS........................          624  6210 B               ...................  ......................
    GC/MS/Isotope................         1624  ...................  ...................  ......................
25. Chloroethane:
    GC/ELCD......................          601  6230 B               ...................  ......................
    GC/MS........................          624  6210 B               ...................  ......................
    GC/MS/Isotope................         1624  ...................  ...................  ......................
26. 2-Chloroethylvinyl ether:
    GC/ELCD......................          601  6230 B               ...................  ......................
    GC/MS........................          624  6210 B               ...................  ......................
    GC/MS/Isotope................         1624  ...................  ...................  ......................
27. Chloroform:                                 ...................  ...................  Note, p. 130.
    GC/ELCD......................          601  6230 B               ...................  ......................
    GC/MS........................          624  6210 B               ...................  ......................
    GC/MS/Isotope................         1624  ...................  ...................  ......................
28. Chloromethane:                              ...................  ...................  ......................
    GC/ELCD......................          601  6230 B               ...................  ......................
    GC/MS........................          624  6210 B               ...................  ......................
    GC/MS/Isotope................         1624  ...................  ...................  ......................
29. 2-Chloronaphthalene:                        ...................  ...................  ......................
    GC/ECD.......................          612  ...................  ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
30. 2-Chlorophenol:                             ...................  ...................  ......................
    GC/FID.......................          604  6420 B               ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
31. 4-Chlorophenylphenyl ether:                 ...................  ...................  ......................
    GC/ELCD......................          611  ...................  ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................

[[Page 15004]]


    GC/MS/Isotope................         1625  ...................  ...................  ......................
32. Chrysene:                                   ...................  ...................  ......................
    GC/FID.......................          610  6440 B               ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
    HPLC/UV......................          610  6440 B               D4657-92             ......................
33. Dibenzo(a,h)anthracene:                     ...................  ...................  ......................
    GC/FID.......................          610  6440 B               ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
    HPLC/UV......................          610  6440 B               D4657-92             ......................
34. Dibromochloromethane:                       ...................  ...................  ......................
    GC/ELCD......................          601  6230 B               ...................  ......................
    GC/MS........................          624  6210 B               ...................  ......................
    GC/MS/Isotope................         1624  ...................  ...................  ......................
35. 1,2-Dichlorobenzene:                        ...................  ...................  ......................
    GC/ELCD......................          601  6230 B               ...................  ......................
    GC/PID.......................          602  6220 B               ...................  ......................
    GC/ECD.......................          612  ...................  ...................  ......................
    GC/MS........................     624, 625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
36. 1,3-Dichlorobenzene:                        ...................  ...................  ......................
    GC/ELCD......................          601  6230 B               ...................  ......................
    GC/PID.......................          602  6220 B               ...................  ......................
    GC/ECD.......................          612  ...................  ...................  ......................
    GC/MS........................     624, 625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
37. 1,4-Dichlorobenzene:                        ...................  ...................  ......................
    GC/ELCD......................          601  6230 B               ...................  ......................
    GC/PID.......................          602  6220 B               ...................  ......................
    GC/ECD.......................          612  ...................  ...................  ......................
    GC/MS........................     624, 625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
38. 3,3-Dichlorobenzidine:                      ...................  ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
    HPLC/ELCD....................          605  ...................  ...................  ......................
39. Dichlorodifluoromethane:                    ...................  ...................  ......................
    GC/ELCD......................          601  6230 B               ...................  ......................
40. 1,1-Dichloroethane:                         ...................  ...................  ......................
    GC/ELCD......................          601  6230 B               ...................  ......................
    GC/MS........................          624  6210 B               ...................  ......................
    GC/MS/Isotope................         1624  ...................  ...................  ......................
41. 1,2-Dichloroethane:                         ...................  ...................  ......................
    GC/ELCD......................          601  6230 B               ...................  ......................
    GC/MS........................          624  6210 B               ...................  ......................
    GC/MS/Isotope................         1624  ...................  ...................  ......................
42. 1,1-Dichloroethene:                         ...................  ...................  ......................
    GC/ELCD......................          601  6230 B               ...................  ......................
    GC/MS........................          624  6210 B               ...................  ......................
    GC/MS/Isotope................         1624  ...................  ...................  ......................
43. trans-1,2-Dichloroethene:                   ...................  ...................  ......................
    GC/ELCD......................          601  6230 B               ...................  ......................
    GC/MS........................          624  6210 B               ...................  ......................
    GC/MS/Isotope................         1624  ...................  ...................  ......................
44. 2,4-Dichlorophenol:                         ...................  ...................  ......................
    GC/FID.......................          604  6420 B               ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
45. 1,2-Dichloropropane:                        ...................  ...................  ......................
    GC/ELCD......................          601  6230 B               ...................  ......................
    GC/MS........................          624  6210 B               ...................  ......................
    GC/MS/Isotope................         1624  ...................  ...................  ......................
46. cis-1,3-Dichloropropene:                    ...................  ...................  ......................
    GC/ELCD......................          601  6230 B               ...................  ......................
    GC/MS........................          624  6210 B               ...................  ......................
    GC/MS/Isotope................         1624  ...................  ...................  ......................
47. trans-1,3-Dichloropropene:                  ...................  ...................  ......................

[[Page 15005]]


    GC/ELCD......................          601  6230 B               ...................  ......................
    GC/MS........................          624  6210 B               ...................  ......................
    GC/MS/Isotope................         1624  ...................  ...................  ......................
48. Diethyl phthalate:                          ...................  ...................  ......................
    GC/ECD.......................          606  ...................  ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
49. 2,4-Dimethylphenol:                         ...................  ...................  ......................
    GC/FID.......................          604  6420 B               ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
50. Dimethyl phthalate:                         ...................  ...................  ......................
    GC/ECD.......................          606  ...................  ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
51. Di-n-butyl phthalate:                       ...................  ...................  ......................
    GC/ECD.......................          606  ...................  ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
52. Di-n-octyl phthalate:                       ...................  ...................  ......................
    GC/ECD.......................          606  ...................  ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
53. 2,3-Dinitrophenol:
    GC/FID.......................          604  6420 B               ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
54. 2,4-Dinitrotoluene:
    GC/ECD.......................          609  ...................  ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
55. 2,6-Dinitrotoluene
    GC/ECD.......................          609
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
56. Epichlorohydrin..............  ...........  ...................  ...................  Note 3, p. 130; Note
                                                                                           6, p. S102.
57. Ethylbenzene:
    GC/PID.......................          602  6220 B               ...................  ......................
    GC/MS........................          624  6210 B               ...................  ......................
    GC/MS/Isotope................         1624  ...................  ...................  ......................
58. Fluoranthene:
    GC/FID.......................          610  6440 B               ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
    HPLC/UV......................          610  6440 B               D4657-92             ......................
59. Fluorene:
    GC/FID.......................          610  6440 B               ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
    HPLC/UV......................          610  6440B                D4657-92             ......................
60. Hexachlorobenzene:
    GC/ECD.......................          612  ...................  ...................  ......................
    GC/MS........................          625  6410B                ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
61. Hexachlorobutadiene:
    GC/ECD.......................          612  ...................  ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
62. Hexachlorocyclopentadiene:
    GC/ECD.......................          612  ...................  ...................  ......................
    GC/MS........................      \5\ 625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
63. Hexachloroethane:              ...........  ...................  ...................  616
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
64. Ideno(1,2,3-cd) pyrene:

[[Page 15006]]


    GC/FID.......................          610  6440 B               ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................
    HPLC/UV......................          610  6440 B               D4657-92             ......................
65. Isophorone:
    GC/ECD.......................          609  ...................  ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
66. Methylene chloride:            ...........  ...................  ...................  Note 3, p. 130
    GC/ELCD......................          601  6230 B               ...................  ......................
    GC/MS........................          624  ...................  ...................  ......................
    GC/MS/Isotope................         1624  ...................  ...................  ......................
67. 2-Methyl-4,6-dinitrophenol:
    GC/ECD.......................  ...........  6420 B               ...................  ......................
    GC/FID.......................          604  6420 B               ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
68. Naphthalene:
    GC/FID.......................          610  6440 B               ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
    HPLC/UV......................          610  6440 B               ...................  ......................
69. Nitrobenzene:
    GC/ECD.......................          609  ...................  ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................
70. 2-Nitrophenol:
    GC/ECD.......................  ...........  6420 B               ...................  ......................
    GC/FID.......................          604  6420 B               ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
71. 4-Nitrophenol:
    GC/ECD.......................  ...........  6420B                ...................  ......................
    GC/FID.......................          604  6420B                ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
72. N-Nitrosodimethylamine:
    GC/NPD.......................          607  ...................  ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
73. N-Nitrosodi-n-propylamine:
    GC/NPD.......................          607  ...................  ...................  ......................
    GC/MS........................      \5\ 625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
74. N-Nitrosodiphenylamine:
    GC/NPD.......................          607  ...................  ...................  ......................
    GC/MS........................      \5\ 625  6410B                ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
75. 2,2-Oxybis(1-chloropropane):
    GC/ELCD......................          611  ...................  ...................  ......................
    GC/MS........................          614  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
76. PCB-1016:                      ...........  ...................  ...................  Note 3, p. 43.
    GC/ECD.......................          608  ...................  ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
77. PCB-1221:                      ...........  ...................  ...................  Note 3, p. 43.
    GC/ECD.......................          608  ...................  ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
78. PCB-1232:                      ...........  ...................  ...................  Note 3, p. 43.
    GC/ECD.......................          608  ...................  ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
79. PCB-1242:                      ...........  ...................  ...................  Note 3, p. 43.
    GC/ECD.......................          608  ...................  ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
80. PCB-1248:
    GC/ECD.......................          608  ...................  ...................  ......................
    GC/MS........................          625  ...................  ...................  ......................
81. PCB-1254:                      ...........  ...................  ...................  Note 3, p. 43.

[[Page 15007]]


    GC/ECD.......................          608  ...................  ...................
    GC/MS........................          625  6410 B               ...................  ......................
82. PCB-1260:                      ...........  ...................  ...................  Note 3, p. 43.
    GC/ECD.......................          608  6630 B               ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
83. Pentachlorophenol:             ...........  ...................  ...................  Note 3, p. 140.
    GC/ECD.......................  ...........  6630 B               ...................  ......................
    GC/FID.......................          604  ...................  ...................  ......................
    GC/MS........................          625  ...................  ...................  ......................
    GC/MS/Isotope................         1625  6410 B               ...................  ......................
84. Phenanthrene:                  ...........  ...................  ...................  ......................
    GC/FID.......................          610  6440 B               ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
    HPLC/UV......................          610  6440 B               D4657-92             ......................
85. Phenol:                        ...........  ...................  ...................  ......................
    GC/FID.......................          604  6420 B               ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
86. Pyrene:                        ...........  ...................  ...................  ......................
    GC/FID.......................          610  6440 B               ...................  ......................
    GC/MS........................          625  ...................  ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
    HPLC/UV......................          610  6440B                D4675-92             ......................
87. 2,3,7,8-Tetrachlorodibenzo-p-  ...........  ...................  ...................  Note 3, p. 130.
 dioxin:
    GC/MS........................       5a 613  ...................  ...................  ......................
88. 1,1,2,2-Tetrachloroethane:     ...........  ...................  ...................  Note 3, p. 130.
    GC/ELCD......................          601  6230 B               ...................  ......................
    GC/MS........................          624  6210 B               ...................  ......................
    GC/MS/Isotope................         1624  ...................  ...................  ......................
89. Tetrachloroethene:             ...........  ...................  ...................  Note 3, p. 130.
    GC/ELCD......................          601  6230 B               ...................  ......................
    GC/MS........................          624  6210 B               ...................  ......................
    GC/MS/Isotope................         1624  ...................  ...................  ......................
90. Toluene:                       ...........  ...................  ...................  ......................
    GC/PID.......................          602  6220 B               ...................  ......................
    GC/MS........................          624  6210 B               ...................  ......................
    GC/MS/Isotope................         1624  ...................  ...................  ......................
91. 1,2,4-Trichlorobenzene:        ...........  ...................  ...................  Note 3, p. 130.
    GC/ECD.......................          612  ...................  ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
92. 1,1,1-Trichloroethane:         ...........  ...................  ...................  ......................
    GC/ELCD......................          601  6230 B               ...................  ......................
    GC/MS........................          624  6210 B               ...................  ......................
    GC/MS/Isotope................         1624  ...................  ...................  ......................
93. 1,1,2-Trichloroethane:         ...........  ...................  ...................  Note 3, p. 130.
    GC/ELCD......................          601  6230 B               ...................  ......................
    GC/MS........................          624  6210 B               ...................  ......................
    GC/MS/Isotope................         1624  ...................  ...................  ......................
94. Trichloroethene:               ...........  ...................  ...................  ......................
    GC/ELCD......................          601  6230 B               ...................  ......................
    GC/MS........................          624  6210 B               ...................  ......................
    GC/MS/Isotope................         1624  ...................  ...................  ......................
95. Trichlorofluoromethane:        ...........  ...................  ...................  ......................
    GC/ELCD......................          601  6230 B               ...................  ......................
    GC/MS........................          624  6210 B               ...................  ......................
96. 2,4,6-Trichlorophenol:
    GC/FID.......................          604  6240 B               ...................  ......................
    GC/MS........................          625  6410 B               ...................  ......................
    GC/MS/Isotope................         1625  ...................  ...................  ......................
97. Vinyl chloride:                ...........  ...................  ...................  ......................
    GC/ELCD......................          601  6230 B               ...................  ......................
    GC/MS........................          624  6210 B               ...................  ......................
    GC/MS/Isotope................         1624  ...................  ...................  ......................
----------------------------------------------------------------------------------------------------------------
Table IC notes:
\1\ All parameters are expressed in micrograms per liter (g/L).

[[Page 15008]]


\2\ The full text of Methods 601-613, 624, 625, 1624, and 1625, are given at Appendix A, ``Test Procedures for
  Analysis of Organic Pollutants'', of this Part 136. The standardized test procedure to be used to determine
  the method detection limit (MDL) for these test procedures is given at Appendix B, ``Definition and Procedure
  for the Determination of the Method Detection Limit'' of this Part 136.
\3\ ``Methods for Benzidine: Chlorinated Organic Compounds, Pentachlorophenol and Pesticides in Water and
  Wastewater'', U.S. Environmental Protection Agency, September 1978.
\4\ Method 624 may be extended to screen samples for Acrolein and Acrylonitrile. However, when they are known to
  be present, the preferred method for these two compounds is Method 603 or Method 1624.
\5\ Method 625 may be extended to include benzidine, hexachlorocyclopentadiene, N-nitrosodimethylamine, and N-
  nitrosodiphenylamine. However, when they are known to be present, Methods 605, 607, and 612, or Method 1625,
  are preferred methods for these compounds.
5a 625, Screening only.
\6\ ``Selected Analytical Methods Approved and Cited by the United States Environmental Protection Agency'',
  Supplement to the Fifteenth Edition of Standard Methods for the Examination of Water and Wastewater (1981).
\7\ Each Analyst must make an initial, one-time demonstration of their ability to generate acceptable precision
  and accuracy with Methods 601-603, 624, 625, 1624, and 1625 (See Appendix A of this Part 136) in accordance
  with procedures each in Section 8.2 of each of these Methods. Additionally, each laboratory, on an on-going
  basis must spike and analyze 10% (5% for Methods 624 and 625 and 100% for methods 1624 and 1625) of all
  samples to monitor and evaluate laboratory data quality in accordance with Sections 8.3 and 8.4 of these
  methods. When the recovery of any parameter falls outside the warning limits, the analytical results for that
  parameter in the unspiked sample are suspect and cannot be reported to demonstrate regulatory compliance.
Note: These warning limits are promulgated as an ``interim final action with a request for comments''.
\8\ Methods published by this organization and approved for use under this part may not be modified beyond the
  modifications expressly allowed and defined in each method.
Note: The following acronyms are used in this table:
ECD  Electron Capture Detector
ELCD  Electrolytic Conductivity Detector/Electrochemical Detector
FID  Flame Ionization Detector
GC  Gas Chromatography
GC/MS  Gas Chromatography/Mass Spectrometry
HPLC  High Performance Liquid Chromatography
NPD  Nitrogen Phosphorous Detector
PID  Photoionization Detector
UV  Ultraviolet Detector

                                                                 Table ID.--List of Approved Test Procedures for Pesticides \1\
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                          Other approved methods
                                                              Reference  -----------------------------------------------------------------------------------------------------------------------
       Parameter/methodology                Method           method \2\    Standard methods 18th
                                                                 \7\              ed.\8\                   ASTM \8\                                          Other
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
1. Aldrin.........................  GC/ECD                           608  6630 B & C              D3086-90                    Note 3, p. 7; Note 4, p. 30.
                                    GC/ELCD                 ............  ......................  3086-90                     ..................................................................
                                    GC/MS                            625  6410 B                  ..........................  ..................................................................
2. Ametryn........................  GC                      ............  ......................  ..........................  Note 3, p. 83; Note 6, p. S68.
3. Aminocarb......................  TLC                     ............  ......................  ..........................  Note 3, p. 94; Note 6, p. S16.
4. Atraton........................  GC                      ............  ......................  ..........................  Note 3, p. 83; Note 6, p. S68.
5. Atrazine.......................  GC                      ............  ......................  ..........................  Note 3, p. 83; Note 6, p. S68.
6. Azinphos methyl................  GC                      ............  ......................  ..........................  Note 3, p. 25; Note 6, p. S51.
7. Barban.........................  TLC                     ............  ......................  ..........................  Note 3, p. 104; Note 6, p. S64.
8. -BHC..................  GC/ECD                           608  6630 B &C               3086-90                     Note 3, p. 7.
                                    GC/ELCD                 ............  ......................  D3086-90                    ..................................................................
                                    GC/MS                        \5\ 625  6410 B                  ..........................  ..................................................................
9. -BHC..................  GC/ECD                           608  6630                    3086-90                     ..................................................................
                                    GC/ELCD                 ............  ......................  D3086-90                    ..................................................................
                                    GC/MS                        \5\ 625  6410 B                  ..........................  ..................................................................
10. -BHC.................  GC/ECD                           608  6630 B & C              D3086-90                    ..................................................................
                                    C/ELCD                  ............  ......................  D3086-90                    ..................................................................
                                    GC/MS                        \5\ 625  6410 B                  ..........................  ..................................................................
11. -BHC (Lindane).......  GC/ECD                           608  6630 B & C              3086-90                     Note 3, p. 7; Note 4, p. 30.
                                    GC/ELCD                 ............  ......................  D3086-90                    ..................................................................
                                    GCMS                             625  6410 B                  ..........................  ..................................................................
12. Captan........................  GC/ECD                  ............  6630 B                  D3086-90                    Note 3, p. 7.
                                    GC/ELCD                 ............  ......................  D3086-90                    ..................................................................
13. Carbaryl......................  TLC                     ............  ......................  ..........................  Note 3, p. 94; Note 6, p. S60.
14. Carbophenothion...............  GC                      ............  ......................  ..........................  Note 4, p. 30; Note 6, p. S73.
15. Chlordane.....................  GC/ECD                           608  6630 B & C              3086-90                     Note 3, p. 7.
                                    GC/ELCD                 ............  ......................  D3086-90                    ..................................................................
                                    GC/MS                            625  6410 B                  ..........................  ..................................................................
16. Chloropropham.................  TLC                     ............  ......................  ..........................  Note 3, p. 104; Note 6, p. S64.
17. 2,4-D.........................  GC/ECD                  ............  6640 B                  ..........................  Note 3, p. 115; Note 4, p. 35.
18. 4,4'-D-DDD....................  GC/ECD                           608  6630 B & C              D3086-90                    Note 3, p. 7; Note 4, p. 30.
                                    GC/ELCD                 ............  ......................  D3086-90                    ..................................................................
                                    GC/MS                            625  6410 B                  ..........................  ..................................................................
19. 4,4'-DDE......................  GC/ECD                           608  6630 B &C               3086-90                     Note 3, p. 7; Note 4, p. 30.
                                    GC/ELCD                 ............  ......................  D3086-90                    ..................................................................
                                    GC/MS                            625  6410 B                  ..........................  ..................................................................

[[Page 15009]]


20. 4,4'-DDT......................  GC/ECD                           608  6630 B & C              D3086-90                    Note 3, p. 7; Note 4, p. 30.
                                    GC/ELCD                 ............  ......................  D3086-90                    ..................................................................
                                    GC/MS                            625  6410 B                  ..........................  ..................................................................
21. Demeton-O.....................  GC                      ............  ......................  ..........................  Note 3, p. 25; Note 6, p. S51.
22. Dementon-S....................  GC                      ............  ......................  ..........................  Note 3, p. 25; Note 6, p. S51.
23. Diazinon......................  GC                      ............  ......................  ..........................  Note 3, p. 25; Note 4, p. 30; Note 6, p. S51.
24. Dicamba.......................  GC                      ............  ......................  ..........................  Note 3, p. 115.
25. Dichlofenthion................  GC                      ............  ......................  ..........................  Note 4, p. 30; Note 6, p. S73.
26. Dichloran.....................  GC/ECD                  ............  6630 B & C              ..........................  Note 3, p. 7.
27. Dicofol.......................  GC/ECD                  ............  ......................  D3086-90                    ..................................................................
                                    GC/ELCD                 ............  ......................  D3086-90                    ..................................................................
28. Dieldrin......................  GC/ECD                           608  6630 B & C              ..........................  Note 3, p. 7; Note 4, p. 30.
                                    GC/MS                            625  6410 B                  ..........................  ..................................................................
29. Dioxathion....................  GC                      ............  ......................  ..........................  Note 4, p. 30; Note 6, p. S73.
30. Disulfoton....................  GC                      ............  ......................  ..........................  Note 3, p. 25; Note 6, p. S51.
31. Diuron........................  TLC                     ............  ......................  ..........................  Note 3, p. 104; Note 6, p. S64.
32. Endosulfan I..................  GC/ECD                           608  6630 B & C              D3086-90                    Note 3, p. 7.
                                    GC/ELCD                 ............  ......................  D3086-90                    ..................................................................
                                    GC/MS                          5 625  6410 B                  ..........................  ..................................................................
33. Endosulfan II.................  GC/ECD                           608  6630 B & C              D3086-90                    Note 3, p. 7.
                                    GC/ELCD                 ............  ......................  D3086-90                    ..................................................................
                                    GC/MS                          5 625  6410 B                  ..........................  ..................................................................
34. Endosulfan Sulfate............  GC                               608  6630 C                  ..........................  ..................................................................
                                    GC/MS                            625  6410 B                  ..........................  ..................................................................
35. Endrin........................  GC/ECD                           608  6630 B & C              D3086-90                    Note 3, p. 7; Note 4, p. 30.
                                    GC/ELCD                 ............  ......................  D3086-90                    ..................................................................
                                    GC/MS                          5 625  6410 B                  ..........................  ..................................................................
36. Endrin aldehyde...............  GC/ECD                           608  ......................  ..........................  ..................................................................
37. Ethion........................  GC                      ............  ......................  ..........................  Note 4, p. 30; Note 6, p. S73.
38. Fenuron.......................  TLC                     ............  ......................  ..........................  Note 3, p. 104; Note 6, p. S64.
39. Fenuron-TCA...................  TLC                     ............  ......................  ..........................  Note 3, p. 104; Note 6, p. S64.
40. Heptachlor....................  GC/ECD                           608  6630 B & C              D3086-90                    Note 3, p. 7; Note 4, p. 30.
                                    GC/ELCD                 ............  ......................  D3086-90                    ..................................................................
                                    GC/MS                            625  6410 B                  ..........................  ..................................................................
41. Heptachlor epoxide............  GC/ECD                           608  6630 B                  D3086-90                    Note 3, p. 7; Note 4, p. 30.
                                    GC/ELCD                 ............  ......................  D3086-90                    ..................................................................
                                    GC/MS                            625  6410 B                  ..........................  Note 6, p. S73.
42. Isodrin.......................  GC                      ............  ......................  ..........................  Note 4, p. 30; Note 6, p. S73.
43. Linuron.......................  GC                      ............  ......................  ..........................  Note 3, p. 104; Note 6, p. S64.
44. Malathion.....................  GC/ECD                  ............  6630 C                  ..........................  Note 3, p. 25; Note 4, p. 30; Note 6, p. S51.
45. Methiocarb....................  TLC                     ............  ......................  ..........................  Note 3, p. 94; Note 6, p. S60.
46. Methoxychlor..................  GC/ECD                  ............  6630 B & C              D3086-90                    Note 3, p. 7; Note 4, p. 30.
                                    GC/ELCD                 ............  ......................  D3086-90                    ..................................................................
47. Mexacarbate...................  TLC                     ............  ......................  ..........................  Note 3, p. 94; Note 6, p. S60.
48. Mirex.........................  GC/ECD                  ............  6630 B & C              ..........................  Note 3, p. 7.
49. Monuron.......................  TLC                     ............  ......................  ..........................  Note 3, p. 104; Note 6, p. S64.
50. Monuron.......................  TLC                     ............  ......................  ..........................  Note 3, p. 104; Note 6, p. S64.
51. Nuburon.......................  TLC                     ............  ......................  ..........................  Note 3, p. 104; Note 6, p. S64.
52. Parathion methyl..............  GC/ECD                  ............  6630 C                  ..........................  Note 3, p. 25; Note 4, p. 30.
53. Parathion ethyl...............  GC/ECD                  ............  6630 C                  ..........................  Note 3, p. 25.
54. PCNB..........................  GC/ECD                  ............  6630 B & C              ..........................  Note 3, p. 7.
55. Perthane......................  GC/ECD                  ............  ......................  D3086-90                    ..................................................................
                                    GC/ELCD                 ............  ......................  D3086-90                    ..................................................................
56. Prometron.....................  GC                      ............  ......................  ..........................  Note 3, p. 83; Note 6, p. S68.
57. Prometryn.....................  GC                      ............  ......................  ..........................  Note 3, p. 83; Note 6, p. S68.
58. Propazine.....................  GC                      ............  ......................  ..........................  Note 3, p. 83; Note 6, p. S68.
59. Propham.......................  TLC                     ............  ......................  ..........................  Note 3, p.104; Note 6, p. S64
60. Propoxur......................  TLC                     ............  ......................  ..........................  Note 3, p. 94; Note 6, p. S60.
61. Secbumeton....................  TLC                     ............  ......................  ..........................  Note 3, p. 83; Note 6, p. S68.
62. Siduron.......................  TLC                     ............  ......................  ..........................  Note 3, p. 104; Note 6, p. S64.
63. Simazine......................  GC                      ............  ......................  ..........................  Note 3, p. 83; Note 6, p. S68.
64. Strobane......................  GC/ECD                  ............  6630 B & C              ..........................  Note 3, p. 7.
65. Swep..........................  TLC                     ............  ......................  ..........................  Note 3, p. 104; Note 6, p. S64.
66. 2,4,5-T.......................  GC/ECD                  ............  6640 B                  ..........................  Note 3, p. 115; Note 4, p. 35.
67. 2,4,5-TP (Silvex).............  GC/ECD                  ............  6640 B                  ..........................  Note 3, p. 115.
68. Terbuthylazine................  GC                      ............  ......................  ..........................  Note 3, p. 83; Note 6, p. S68.
69. Toxaphene.....................  GC/ECD                           608  6630 B & C              ..........................  Note 3, p. 7; Note 4, p. 30.
                                    GC/ELCD                 ............  ......................  3086-90                     ..................................................................

[[Page 15010]]


                                    GC/MS                            625  6410 B                  D3086-90                    ..................................................................
70. Trifluralin...................  GC                      ............  6630 B                  ..........................  Note 3, p. 7.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Table ID notes:
\1\ Pesticides are listed in this table by common name for the convenience of the reader. Additional pesticides may be found under Table 1C, where entries are listed by chemical name.
\2\ The full text of Methods 608 and 625 are given at Appendix A. ``Test Procedures for Analysis of Organic Pollutants'' of this Part 136. The standardized test procedure to be used to
  determine the method detection limit (MDL) for these test procedures is given at Appendix B. ``Definition and Procedure for the Determination of the Method Detection Limit'', of this Part
  136.
\3\ Methods for Benzidine, Chlorinated Organic Compounds, Pentachlorophenol and Pesticides in Water and Wastewater'' U.S. Environmental Protection Agency, September 1978. This
  includes thin-layer chromatography (TLC) methods.
\4\ ``Methods for Analysis of Organic Substances in Water and Fluvial Sediments'', Techniques of Water-Resources Investigations of the U.S. Geological Survey, Book 5, Chapter A3 (1987).
\5\ The method may be extended to include -BHC, -BHC, endosulfan I, endosulfan II, and endrin. However, when they are known to exist, Method 608 is the preferred method.
\6\ ``Selected Analytical Methods Approved and Cited by the United States Environmental Protection Agency''. Supplement to the Fifteenth Edition of Standard Methods for the Examination of
  Water and Wastewater (1981).
\7\ Each analyst must make an initial, one-time, demonstration of their ability to generate acceptable precision and accuracy with Methods 608 and 625 (See Appendix A of this Part 136) in
  accordance with procedures given in Section 8.2 of each of these methods. Additionally, each laboratory, on an on-going basis, must spike and analyze 10% of all samples analyzed with Method
  608 or 5% of all samples analyzed with Method 625 to monitor and evaluate laboratory data quality in accordance with Sections 8.3 and 8.4 of these methods. When the recovery of any parameter
  falls outside the warning limits, the analytical results for that parameter in the unspiked sample are suspect and cannot be reported to demonstrate regulatory compliance. These quality
  control requirements also apply to the Standard Methods, ASTM Methods, and other Methods cited.
Note: These warning limits are promulgated as an ``Interim final action with a request for comments.''
\8\ Methods published by this organization and approved for use under this part may not be modified beyond the modifications expressly allowed and defined in each method.
Note: The following acronyms are used in this table:

   ECD: Electron Capture Detector.
  ELCD: Electrolytic Conductivity Detector/Electrochemical Detector.
  FID: Flame Ionization Detector.
  GC: Gas Chromatography.
GC/MS: Gas Chromatography/Mass Spectrometry.

* * * * *

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[[Page 15018]]

    (c) Under certain circumstances, the Regional Administrator or the
Director in the Region or State where the discharge will occur may
determine that an additional parameter or pollutant of concern must be
reported. Under such circumstances, an additional test procedure for
the analysis of the pollutant may be specified by the Regional
Administrator, or the Director, upon the recommendation of the Director
of the Analytical Methods Staff.
    (d) Sample preservation procedures, container materials, and
maximum allowable holding times for parameters and pollutants cited in
Tables IA, IB, IC, ID, and IE are prescribed in Table II. Any person
may apply for a variance from the prescribed preservation techniques,
container materials, and maximum holding times applicable to samples
collected from a specific discharge. An application for a variance may
be made by letter to the Regional Administrator in the Region in which
the discharge will occur. Sufficient data should be provided to ensure
such variance does not adversely affect the integrity of the sample.
Such data will be forwarded by the Regional Administrator to the
Director of the Analytical Methods Staff for technical review and
recommendations for action on the variance application. Upon receipt of
a recommendation from the Director of the Analytical Methods Staff, the
Regional Administrator may grant a variance applicable to samples
collected from the specific discharge for which the application for
variance was made. A decision to approve or deny a variance will be
made within 90 days of receipt of a complete application by the
Regional Administrator.
* * * * *
    4. Section 136.4 is proposed to be revised to read as follows:

Sec. 136.4  Modifications to reference methods.

    A reference method listed in tables IB, IC, or ID of this part 136
may be modified to improve separations, lower the costs of
measurements, reduce or eliminate interferences, or for other purposes,
provided that the modification is not explicitly prohibited in the
reference method and provided that the laboratory modifying the
reference method meets the requirements in this section, performs the
standardized QC tests, and demonstrates that the QC acceptance criteria
and the requirements specified at Appendixes E, F, and G of this part
are met. A laboratory that wishes to use a new or modified wastewater
method must demonstrate that the method detection limit (MDL) specified
in the reference method can be achieved. Alternatively, if the effluent
limitation to be measured is above the MDL, laboratories must
demonstrate that the minimum level (ML) determined with the new or
modified wastewater method is at or below \1/3\ the effluent
limitation. Demonstration of a valid detection limit requires use of an
MDL study in accordance with the procedure at 40 CFR part 136 Appendix
B. If the MDL determined with the new or modified method is not
acceptable, the method may not be used. Specified detection limits are
usually analyte-specific. For any given analyte, the specified
detection limit may vary between a wastewater and drinking water
reference method.
    (a) Tier 1: modification of a reference method for application in a
single laboratory to one or more matrix types.
    (1) Application to a single matrix type.
    (i) A laboratory may modify a reference method listed in tables IB,
IC, and ID for determination of an analyte of concern in a specific
matrix type, provided that the laboratory:
    (A) Performs the standardized QC tests, including a test of initial
precision and recovery (IPR) on a reagent water matrix;
    (B) Performs the matrix spike (MS) and matrix spike duplicate (MSD)
tests on the matrix type to which the modification is to be applied;
    (C) Meets the QC acceptance criteria in the reference method or
that apply to the reference method in the table of QC acceptance
criteria for wastewater methods at Sec. 136.3 Table IF;
    (D) Documents the results of the QC tests using the checklists in
Appendix E of this part;
    (E) Maintains the results of the QC tests and other tests on file
for inspection by EPA and/or the approved State NPDES authority.
    (ii) After the laboratory has demonstrated application of a method
modification to a given matrix type by meeting the MS/MSD QC acceptance
criteria, only that laboratory may subsequently apply that method
modification to that given matrix type.
    (iii) A laboratory may apply a given method modification to
additional matrix types if the laboratory validates the modification on
each matrix type by performing a matrix spike (MS) and matrix spike
duplicate (MSD) test and meeting the MS/MSD QC acceptance criteria for
precision and recovery for each matrix type.
    (2) Application to multiple matrix types. After a laboratory has
validated a given method modification on a minimum of nine (9) matrix
types in accordance with the procedures given in paragraph (a)(1) of
this section, the laboratory may subsequently apply that method
modification to other matrix types without validating the method
modification on those subsequent matrix types, provided that:
    (i) The following are included in the matrix types validated:
    (A) Effluent from a publicly-owned treatment works (POTW);
    (B) ASTM D 5905, Standard Specification for Substitute Wastewater;
    (C) Sewage sludge, if sludge will be in the permit; and
    (D) ASTM D 1141, Standard Specification for Substitute Ocean Water,
if ocean water will be in the permit.
    (ii) At least one of the matrix types in paragraph (a)(2)(i) of
this section has at least one of the following characteristics: total
suspended solids (TSS) greater than 40 mg/L, total dissolved solids
(TDS) greater than 100 mg/L, oil and grease greater than 20 mg/L,
sodium chloride (NaCl) greater than 120 mg/L, and calcium carbonate
(CaCO3) greater than 140 mg/L.
    (iii) The matrix spike (MS) and matrix spike duplicate (MSD)
recovery and the relative percent difference are within the QC
acceptance criteria given for the analyte in the reference method or as
supplemented by the QC acceptance criteria specified for wastewater
methods at Sec. 136.3 Table IF. If the method modification is to be
applied to multiple media, validation must include a minimum of one
matrix type from each additional medium in addition to the matrix types
listed in this paragraph. If all QC acceptance criteria are not met for
a given matrix type, the modification may not be applied to that matrix
type.
    (b) Tier 2: modification of a reference method for application by
all laboratories to one or more matrix types within a single industrial
category or subcategory.
    (1) A person may modify a reference method for application by all
laboratories to determination of an analyte of concern in a single
matrix type in a single industrial category or subcategory, provided
that the modification is not explicitly prohibited in the reference
method and provided that the modification is validated in a minimum of
three (3) laboratories, each of which test the same three (3) matrix
types and each matrix type is from a different facility in the
industrial category or subcategory (a minimum of nine (9) tests). Each
laboratory must meet the requirements in paragraph (a)(1)(i) of this
section. After the tests in all three laboratories have met all QC
acceptance criteria for the reference

[[Page 15019]]

method, the modified reference method may be applied by laboratories
nationwide to that matrix type in that industrial category or
subcategory only.
    (2) A person who modifies and validates a method modification under
Tier 2 may submit that modification to EPA for a letter of approval
using the procedures specified in Appendix F and G of this part. The
information that must be submitted includes the results of the
performance tests required by paragraph (b)(1) of this section. This
information and other detailed information that must be submitted and
the format for submission are given in Appendixes E, F, and G of this
part.
    (3) A person who modifies and validates a method modification under
Tier 2 may submit that modification to EPA and for approval and
inclusion in a table in this part 136. The information that must be
submitted includes the results of the performance tests required by
paragraph (b)(1) of this section, and the detailed information
specified in Appendixes E, F, and G of this part.
    (4) A person may modify a reference method for application by all
laboratories to determination of an analyte of concern in additional
matrix types within a single industrial category or subcategory,
provided that the modification is validated in each additional matrix
type according to the requirements in paragraph (b)(1) of this section.
    (c) Tier 3: modification of a reference method for application by
all laboratories to all matrix types in all industrial categories and
subcategories (nationwide modification).
    (1) A person may modify a reference method for application by all
laboratories to determination of an analyte of concern in all matrix
types, provided that the modification is validated in an
interlaboratory method validation study or in a study with a minimum of
nine (9) different laboratories each of which test a minimum of one
sample from a set representing a minimum of nine (9) different matrix
types for a total of a minimum of nine unique samples. Each of the nine
(9) matrix types must be from a different industrial category or
subcategory. Each laboratory must meet the requirements in paragraph
(a)(1)(i) of this section and, the nine matrix types must collectively
meet all of the criteria in paragraphs (a)(2)(i), (ii), and (iii) of
this section. After the modification has been validated, it may be
applied by laboratories nationwide to all matrix types.
    (2) A person who modifies and validates a method modification under
Tier 3 may submit that modification to EPA for a letter of approval.
The information that must be submitted includes the results of the
performance tests required by paragraph (b)(1) of this section. This
information and other detailed information that must be submitted and
the format for submission are given in Appendixes E, F, and G of this
part.
    (3) A person who modifies and validates a method modification under
Tier 3 may submit that modification to EPA and for approval and
inclusion in a table in this part 136. The information that must be
submitted includes the results of the performance tests required by
paragraph (c)(1) of this section. This information and other detailed
information that must be submitted and the format for submission are
given in Appendixes E, F, and G of this part.
    (d) A decision to recommend proposal of a Tier 2 or Tier 3 method
modification will be made by the Director of the Analytical Methods
Staff within 90 days of receipt of a complete application.
    5. Section 136.5 is proposed to be revised to read as follows:

Sec. 136.5  New methods.

    A person may apply to EPA for use of a new method for determination
of an analyte of concern, provided that the new method meets the
requirements for validation and format as set forth in this section and
in appendixes E, F, and G of this part. A new method must meet the MDL
criteria specified at Sec. 136.4. A new method must: be documented in
accordance with requirements in appendixes E, F, and G of this part;
contain standardized QC as defined at Sec. 136.2; contain QC acceptance
criteria that have been developed in accordance with the requirements
detailed in appendixes E, F, and G of this part; employ a determinative
technique for an analyte of concern with selectivity or sensitivity
equal or superior to the selectivity or sensitivity of the
determinative technique in any approved method, and that differs from
the determinative techniques employed for that analyte in all approved
methods; and be accompanied by the information specified at appendix G
of this part. A decision to recommend proposal of a new method will be
made by the Director of the Analytical Methods Staff within 90 days of
receipt of a complete application.
    (a) Tier 1: application of a new method in a single laboratory to
one or more matrix types.
    (1) A person may develop a new method for determination of an
analyte of concern in one or more matrix types by validating the method
and developing QC acceptance criteria from an interlaboratory method
validation study or from a single-laboratory validation study on each
specific matrix type. Details of the single-laboratory method
validation study and development of QC acceptance criteria from a
single-laboratory or interlaboratory method validation study are
specified at Sec. 136.4(a) (1) and (2) and in appendixes E, F, and G of
this part.
    (2) A person who develops a new method under Tier 1 must submit the
method to EPA for a letter of approval. The information that must be
submitted and the format for submission is specified at in appendixes
E, F, and G of this part.
    (b) Tier 2: application of a new method in all laboratories to one
or more matrix types within a single industrial category or
subcategory.
    (1) A person may develop a new method for determination of an
analyte of concern in one or more matrix types within a single
industrial category or subcategory by validating the method and
developing QC acceptance criteria on each matrix type from an
interlaboratory method validation study or from multiple, single-
laboratory validation studies. Details of the multiple, single-
laboratory method validation studies and development of QC acceptance
criteria from these studies or from an interlaboratory method
validation study are specified at Sec. 136.4(b) (1) and (4) and in
appendixes E, F, and G of this part.
    (2) A person who develops a new method under Tier 2 must submit the
method to EPA for approval and inclusion in a table in this part 136.
The information that must be submitted includes the results of the
performance tests required by paragraph (b)(1) of this section. This
information and other detailed information that must be submitted and
the format for submission are given in appendixes E, F, and G of this
part.
    (c) Tier 3: application of a new method by all laboratories to all
matrix types in all industrial categories and subcategories (nationwide
use).
    (1) A person may develop for nationwide use a new method for
determination of an analyte of concern in all matrix types by
validating the method and developing QC acceptance criteria on the
matrix type from an interlaboratory method validation study or from
multiple, single-laboratory validation studies. Details of the
multiple, single-laboratory method validation studies and development
of QC acceptance criteria from these studies or from an interlaboratory
method validation study are specified at

[[Page 15020]]

Sec. 136.4(c)(1) and in appendixes E, F, and G of this part.
    (2) A person who develops a new method under Tier 3 must submit the
method to EPA for approval and inclusion in a table in this part 136.
The information that must be submitted includes the results of the
performance tests required by paragraph (c)(1) of this section. This
information and other detailed information that must be submitted and
the format for submission are given in appendixes E, F, and G of this
part.
    (d) The number and type of required tests, testing laboratories,
matrices, and replicate QC tests for the method validation specified at
Secs. 136.4, 136.5 (a), (b), and (c) and 141.27 depend on the tier at
which the new or modified wastewater or drinking water method is
validated. These requirements are summarized in the following table:

                                     Summary of Validation Requirements for New Methods and Method Modifications \1\
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                             Number of                            Number of analyses required
                                                              ------------------------------------------------------------------------------------------
                      Method application                                       Matrix     Facilities  IPR-reagent   IPR-sample
                                                                   Labs        types         PWSs      water \2\    matrix \3\     MS/MSD      MDL \4\
--------------------------------------------------------------------------------------------------------------------------------------------------------
Tier 1-Single-lab:
    WW/DW--First matrix type or first PWS....................            1            1            1            4            4        \5\ 2            7
    WW--Each addt'l matrix type (8 max.) from any industrial
     category................................................            1            1            1        \6\ 0        \6\ 0        \5\ 2        \6\ 0
    DW--Each addt'l PWS (2 max.).............................            1            1            1        \6\ 0        \6\ 0        \5\ 2        \6\ 0
Tier 2-Multi-lab, single matrix type.........................            3            1            3           12            0        \7\ 6           21
    WW/DW--Each matrix type in a single industrial category
Tier 3-Multi-lab, multiple matrix types......................        \8\ 9            9            9           36            0       \7\ 18           63
    WW only--All matrix types, all industrial categories
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Numbers of analyses in this table do not include background analyses or additional QC tests such as calibration, blanks, etc. Validation
  requirements are based on the intended application of the method. Method application would be designated by tier for wastewater (WW) and drinking
  water (DW) programs. Three would be the maximum number of public water systems (PWSs) that would be required to validate a new or modified drinking
  water method at Tier 1 or 2. Nine would be the maximum number of matrix types (or facilities) that would be required to validate a new or modified
  wastewater method at Tier 1 or 3; at Tier 2 the number would be three matrix types.
\2\ IPR reagent water analyses would be used to validate a method modification and to establish QC acceptance criteria for initial precision and
  recovery (IPR) and ongoing precision and recovery (OPR) for a new method. The required number of IPR analyses, except as noted under footnote 7, would
  be four times the number of laboratories required to validate a method modification or new method because each laboratory would perform a 4-replicate
  IPR test.
\3\ IPR sample matrix analyses would be used to establish QC acceptance criteria for matrix spike/matrix spike duplicate (MS/MSD) recovery and precision
  for a Tier 1 new method only. Would not be required for validation of Tier 2 or 3 new methods because this variability data would be obtained from MS/
  MSD tests. Would not be required for validation of a method modification because MS/MSD data from the reference method would be used.
\4\ A method detection limit (MDL) test would be performed in each laboratory using the new or modified method. 40 CFR part 136 Appendix B requires a
  minimum of seven analyses per laboratory to determine an MDL. Each lab involved in validation of a wastewater modification would demonstrate that the
  modified method would achieve the detection limits specified in the regulations at 40 CFR parts 136 and 141 and/or in chapter 6 of the Streamlining
  Guide (EPA 1996a).
\5\ MS/MSD analyses would be required only for a method modification because, for new methods, the MS/MSD QC acceptance criteria would be established by
  the 4-replicate sample matrix IPR test. For modified methods, the MS/MSD test would demonstrate that the reference method MS/MSD QC acceptance
  criteria have been met.
\6\ The MDL, reagent water IPR, and sample matrix IPR tests would not have to be repeated after the first matrix type, facility, or PWS was validated.
\7\ For validation of a new method, the MS/MSD analyses would establish QC acceptance criteria for MS/MSD recovery and precision. For validation of a
  method modification, the MS/MSD analyses would demonstrate that reference method MS/MSD recovery and precision have been met. The required number of
  MS/MSD analyses would be two times the number of facilities, PWSs or matrix types tested.
\8\ The number of laboratories and samples would vary if a conventional interlaboratory study is used.

    6. Appendix A to 40 CFR part 136 is removed and reserved. Appendix
E, Appendix F, and Appendix G are added to 40 CFR part 136 to read as
follows:.

Appendix A to Part 136 [Removed and Reserved]

* * * * *

Appendix E to Part 136--Equivalency Checklists

    The Checklist for Initial Demonstration of Method Performance,
Checklist for Continuing Demonstration of Method Performance, and
Certification Statement (collectively called ``Checklists'') and
instructions for their completion are provided in this appendix.
Because these checklists were developed by EPA's Environmental
Monitoring Management Council (EMMC) for general application across
all EPA programs, the lists contain categories that are not relevant
to approval of drinking water or wastewater methods. Therefore,
these categories are indicated in this appendix by ``NA'' (not
applicable). The EMMC instructions have been annotated, where
appropriate, to clarify each checklist item's applicability to the
approval of drinking water and wastewater methods.

Checklist for Initial Demonstration of Method Performance

    For the demonstration of equivalency, provide a checklist for
each matrix in each medium.
Date:
Page ________ of ________
Laboratory Name & Address:
Facility Name:
Discharge Point ID:
EPA Program and Applicable Regulation:
Medium:

(e.g., wastewater, drinking water, soil, air, waste solid, leachate,
sludge, other)

Analyte or Class of Analytes:

(e.g., barium, trace metals, benzene, volatile organics, etc.)

[[Page 15021]]

                                 Initial Demonstration of Method Performance \1\
----------------------------------------------------------------------------------------------------------------
                                                              Performance criteria \2\
                                                                      based on
                                                             --------------------------   Results    Perf. spec.
                          Category                            Measurement                 obtained     achieved
                                                                quality     Reference                ()
                                                               objective      method
----------------------------------------------------------------------------------------------------------------
1. Written method (addressing all elements in the EMMC
 format) attached
2. Title, number and date/rev. of ``reference method'', if
 applicable 3
3. Copy of the reference method, if applicable, maintained
 at facility
4. Differences between PBM and reference method (if
 applicable) attached
5. Concentrations of calibration standards
6. %RSD or correlation coefficient of calibration regression
7. Performance range tested (with units)
8. Sample(s) used in initial demonstration have recommended
 preservative, where applicable.
9. Sample(s) used in initial demonstration met recommended
 holding times, where applicable
10. Interferences
11. Qualitative identification criteria used
12. Performance Evaluation studies performed for analytes of
 interest, where available:
    Latest study sponsor and title:
    Latest study number:
13. Analysis of external reference material
14. Source of reference material
15. Surrogates used, if applicable
16. Concentrations of surrogates, if applicable
17. Recoveries of surrogates appropriate to the proposed
 use, if applicable
18. Sample preparation
19. Clean-up procedures
20. Method Blank Result
21. Matrix (reagent water, drinking water, sand, waste
 solid, ambient air, etc.)
22. Spiking system, appropriate to method and application
23. Spike concentrations (w/ units corresponding to final
 sample concentration)
24. Source of spiking material
25. Number of replicate spikes
26. Precision (analyte by analyte)
27. Bias (analyte by analyte)
28. Detection Limit (w/ units; analyte by analyte)
29. Confirmation of Detection Limit, if applicable
30. Quantitation Limit (w/ units: analyte by analyte)
31. Qualitative Confirmation
32. Frequency of performance of the Initial Demonstration
33. Other criterion (specify)
34. Other criterion (specify)
----------------------------------------------------------------------------------------------------------------
\1\ Provide a detailed narrative description of the initial demonstration.
\2\ For multi-analyte methods, enter ``see attachment'' and attach a list or table containing the analyte-
  specific performance criteria from the reference method or those needed to satisfy measurement quality
  objectives.
\3\ If a reference method is the source of the performance criteria, the reference method should be appropriate
  to the required application, and the listed criteria should be fully consistent with that reference method.

    Name and signature of each analyst involved in the initial
demonstration of method performance (includes all steps in the proposed
method/modification):

----------------------------------------------------------------------
Name

----------------------------------------------------------------------
Signature

----------------------------------------------------------------------
Date

----------------------------------------------------------------------
Name

----------------------------------------------------------------------
Signature

----------------------------------------------------------------------
Date

----------------------------------------------------------------------
Name

----------------------------------------------------------------------
Signature

----------------------------------------------------------------------
Date

    The certification above must accompany this form each time it is
submitted.

Checklist for Continuing Demonstration of Method Performance

    For the demonstration of equivalency, provide a checklist for
each matrix in each medium.
Page____ of ____
Date:
Laboratory Name & Address:
Facility Name:
Discharge Point ID:
EPA Program and Applicable Regulation:
Medium:
(e.g., wastewater, drinking water, soil, air, waste solid, leachate,
sludge, other)
Analyte or Class of Analytes:
(e.g., barium, trace metals, benzene, volatile organics, etc.)

[[Page 15022]]

                                 Continuing Demonstration of Method Performance
----------------------------------------------------------------------------------------------------------------
                                                                                                     Performance
                                                                Required     Specific     Results      specific
                          Category                             frequency   performance    obtained     achieved
                                                                             criteria                 ()
----------------------------------------------------------------------------------------------------------------
1. Method blank result (taken through all steps in the
 procedure)
2. Concentrations of calibration standards used to verify
 working range (with units), where applicable
3. Calibration verification
4. Laboratory control sample
5. External QC sample (where available)
6. Performance evaluation (PE) studies, if applicable
  Latest study sponsor and title:
  Latest study number:
7. List analytes for which results were ``not acceptable''
 in PE study                                                  ...........  ...........  ...........  ...........
8. Surrogates used, if applicable
9. Concentration of surrogates, if applicable
10. Recovery of surrogates (acceptance range for multi-
 analyte methods), if applicable
11. Matrix
12. Matrix spike compounds
13. Concentration of matrix spike compounds
14. Recoveries of matrix spike compounds
14a. Recoveries of matrix spike duplicate compounds
15. Qualitative identification criteria used
16. Precision (analyte by analyte)
17. Other category (specify)
18. Other category (specify)
----------------------------------------------------------------------------------------------------------------

    Name and signature of each analyst involved in continuing
demonstration of method performance (includes all steps in the proposed
method/modification):

----------------------------------------------------------------------
Name

----------------------------------------------------------------------
Signature

----------------------------------------------------------------------
Date

----------------------------------------------------------------------
Name

----------------------------------------------------------------------
Signature

----------------------------------------------------------------------
Date

----------------------------------------------------------------------
Name

----------------------------------------------------------------------
Signature

----------------------------------------------------------------------
Date

    The certification above must accompany this form each time it is
submitted.

Certification Statement

Page____ of ____
Date:
Laboratory Name & Address:
Facility Name:
Discharge Point ID:
EPA Program and Applicable Regulation:
Medium:
(e.g., water, soil, air)
Analyte or Class of Analytes:
(e.g., barium, trace metals, benzene, volatile organics, etc.;
Attach separate list, as needed.)
We, the undersigned, CERTIFY that:

    1. The method(s) in use at this facility for the analysis/
analyses of samples for the programs of the U.S. Environmental
Protection Agency have met the Initial and any required Continuing
Demonstration of Method Performance Criteria specified by EPA.
    2. A copy of the method used to perform these analyses, written
in EMMC format, and copies of the reference method and laboratory-
specific SOPs are available for all personnel on-site.
    3. The data and checklists associated with the initial and
continuing demonstration of method performance are true, accurate,
complete and self-explanatory.\1\
---------------------------------------------------------------------------

    \1\ True: Consistent with supporting data.
---------------------------------------------------------------------------

    4. All raw data (including a copy of this certification form)
necessary to reconstruct and validate these performance related
analyses have been retained at the facility, and that the associated
information is well organized and available for review by authorized
inspectors.

----------------------------------------------------------------------
Facility Manager's Name and Title

----------------------------------------------------------------------
Signature

----------------------------------------------------------------------
Date

----------------------------------------------------------------------
Quality Assurance Officer's Name

----------------------------------------------------------------------
Signature

----------------------------------------------------------------------
Date

    This certification form must be completed when the method is
originally certified, each time a continuing demonstration of method
performance is documented, and whenever a change of personnel
involves the Facility Manager or the Quality Assurance Officer.
    Accurate: Based on good laboratory practices consistent with
sound scientific principles/practices.
    Complete: Includes the results of all supporting performance
testing.
    Self-Explanatory: Data properly labeled and stored so that the
results are clear and require no additional explanation.

EMMC Checklists Instructions

Checklists Overview

    The Checklists were arrived at through consensus among EPA's
programs by developing performance ``categories'' that allow use of
the same Checklists across the Agency's various programs/projects.
The Checklists may be applied to screening and field techniques as
well as laboratory procedures.
    Implementation of the Checklists is program-specific and a
category that does not apply within a given EPA program will be
indicated by NA (not applicable). Criteria for a specific EPA
program are to be filled in under the ``Performance Criteria''
column; e.g., an Office of Water Reference Method may specify 20%
RSD or a correlation coefficient of 0.995 for the category that
specifies calibration linearity, whereas an Office of Solid Waste
Project may specify a Measurement Quality Objective of 12% RSD or a
correlation coefficient of 0.998 for this category.
    For each EPA program, the Checklists are to be completed for
each matrix within each medium for all matrices and media to which
an alternate method or method modification applies. The EMMC
definition of media is equivalent to the definition at 136.2 of
matrix type. Each completed Checklist must be retained on file at
the laboratory that uses the

[[Page 15023]]

performance-based method (PBM) or method modification and at the
regulated facility from which samples are collected, and must be
submitted to the appropriate Regulatory Authority upon request to
support analysis of those samples to which the PBM or modified
method was applied. (For wastewater and drinking water methods, the
term ``PBM method'' in the preceding sentence is replaced with the
term ``new method'.)

Header:

    Each page of the checklist contains seven lines of header
information, consisting of:
    (1) Date (enter the date that the checklist was completed--
Program/Project implementation plans should indicate whether the
checklist must be submitted to the Regulatory Authority, as well as,
retained on file at the laboratory and regulated facility).
    (2) Laboratory Name & Address (If a commercial contract
laboratory uses the method on behalf of one or more applicable
clients, enter the name and address of the laboratory.)
    (3) Facility Name (enter the name of the water treatment
facility, system, or regulated facility or other program or project
specified entity where the facility maintains an on-site analytical
laboratory. If the method is being employed by a commercial contract
laboratory on behalf of one or more applicable clients, enter the
name of the laboratory followed by a listing of the appropriate
clients).
    (4) Discharge Point Identification Number (enter the discharge
point identification number, if applicable).
    (5) EPA Program & Applicable Regulation (enter the name of the
Agency Program or Project to whom the results will be reported, or
under the auspices of which the data are collected, e.g., ``CAA''
for Clean Air Act monitoring and ``SDWA'' for analyses associated
with the Safe Drinking Water Act).
    (6) Medium (enter the type of environmental sample, e.g.,
drinking water--Note: A separate checklist shall be prepared for
each medium, e.g., for checklists associated with performance-based
methods for SDWA, enter ``Drinking Water'' as the matrix type. As
the evaluations of a performance-based method involve matrix-
specific performance measures, a separate checklist shall be
prepared for each matrix. The ``medium'' is the environmental sample
type to which the performance-based method applies, whereas the
performance category ``matrix'', appearing in the body of the
checklists refers to the specific sample type within the ``Medium''
that was spiked, e.g., for ``medium'' hazardous waste, the checklist
category ``matrix'' may be solvent waste. For wastewater and
drinking water methods, the term ``medium'' is replaced with the
term ``matrix'.
    (7) Analyte or Class of Analytes, where available. (As many
methods apply to a large number of analytes, it is not practical to
list every analyte in this field, as indicated on the form, the
class of analytes may be specified here, i.e., volatile organics.
However, if such a classification is used, a separate list of
analytes and their respective Chemical Abstract Service Registry
Numbers (CAS #) must be attached to the checklist).

Initial Demonstration of Method Performance Checklist

    The Initial Demonstration of Method Performance involves
multiple spikes into a defined sample matrix (e.g., wastewater
medium, paper plant effluent matrix), to demonstrate that the
Performance-based Method meets the Program or Project Performance
Criteria based on the performance of established ``Reference
Method'' or based on ``Measurement Quality Objectives'' (formerly
called Data Quality Objectives). This exercise is patterned after
the ``Initial Demonstration of Capability'' delineated in a number
of the Agency's published methods (Reference Methods).
    Footnote #1 indicates that a detailed narrative description of
the initial demonstration procedure is to be provided.
    Footnote #2 indicates that for multi-analyte methods, the range
of performance criteria for the analytes may be entered, but an
analyte-specific performance criteria is to be attached. In general,
when using the checklists, if the criteria or performance are
lengthy, attach as a separate sheet, and enter ``see attached'' for
this item.
    Footnote #3 indicates that if a reference method is the source
of the performance criteria, the reference method should be
appropriate to the required application and the listed criteria
should be fully consistent with that reference method. The reference
method name and EPA number (where applicable) should be delineated
in the program/project implementation plan, e.g., by the Program
Office or the Project Officer/Manager.
    There are 34 numbered entries in the body of the checklist--
NOTE: Under normal circumstances, it would never be acceptable to
answer ``No'' to any of these performance categories, or fail to
attach the requested materials (categories not applicable to
drinking or wastewater methods are marked with ``NA''):
    #1. Written Method (addressing all elements in the EMMC format)
    The details of the method used for analysis must be described in
a version of the method written in EMMC format, which is specified
for drinking water and wastewater methods at 40 CFR part 136
Appendix F. The EMMC method format includes the following: 1.0 Scope
& Application; 2.0 Summary of Method; 3.0 Definitions; 4.0
Interferences; 5.0 Safety; 6.0 Equipment & Supplies; 7.0 Reagents &
Standards; 8.0 Sample Collection, Preservation & Storage; 9.0
Quality Control; 10.0 Calibration & Standardization; 11.0
Procedures; 12.0 Data Analysis & Calculations; 13.0 Method
Performance; 14.0 Pollution Prevention; 15.0 Waste Management; 16.0
References; 17.0 Tables, Diagrams, Flowcharts & Validation Data.
While this format may differ from that used in standard operation
procedures (SOPs) in a given laboratory, the use of a consistent
format is essential for the efficient and effective evaluation by
inspectors, program and project managers/officers.
    #2. Title, Number and date/revision of ``Reference Method'' if
applicable.
    For Example Polychlorinated Dioxins and Furans, EPA Method 1613,
Revision B, October, 1994.
    #3. Copy of the reference method, if applicable, maintained at
the facility.
    A copy of the reference method must be kept available for all
laboratory personnel, however, it need not be attached to the
checklist itself.
    #4. Differences between PBM and reference method attached.
    The laboratory must summarize the differences between the
reference method and the performance-based method and attach this
summary to the checklist. This summary should focus on significant
difference in techniques (e.g., changes beyond the flexibility
allowed in the reference method), not minor deviations such as the
glassware used.
    #5. Concentrations of calibration standards.
    The range of the concentrations of materials used to establish
the relationship between the response of the measurement system and
analyte concentration. This range must bracket any action, decision
or regulatory limit. In addition, this range must include the
concentration range for which sample results are measured and
reported (when samples are measured after sample dilution/
concentration).
    #6. % RSD or Slope/Correlation Coefficient of Calibration
Regression.
    This performance category refers to quantitative measures
describing the relationship between the amount of material
introduced into the measurement system and the response of the
system, e.g., analytical instrument. A linear response is generally
expected and is typically measured as either a linear regression or
inorganic analytes, or as the relative standard deviation (or
coefficient of variation) of the response factors or calibration
factors for organic analytes. Traditional performance specifications
considered any regression line with a correlation coefficient (r) of
0.995 or greater as linear. Also, for organic analytes, a relative
standard deviation (RSD) of 25% or less is considered linear. The
calibration relationship is not necessarily limited to a linear
relationship. However, it should be remembered if the Program/
Project Office or Officer/Managers specifies other calibration
relationships, e.g., quadratic fit, more calibration standards are
generally necessary to accurately establish the calibration. If
applicable, a calibration curve, graphical representation of the
instrument response versus the concentration of the calibration
standards, should be attached.
    #7. Performance Range Tested (with units).
    This range must reflect the actual range of sample
concentrations that were tested and must include the concentration
units. Since the procedures may include routine sample dilution or
concentration, the performance range may be broader than the range
of the concentrations of the calibration standards.
    #8. Sample(s) used in initial demonstration have recommended
preservative, where applicable.
    Unless preservation have been specifically evaluated, this entry
should be taken directly from the reference method/standard. If
preservation has been evaluated, include the study description and
conclusions of that evaluation, with a reference to the specific
study description. The data must be attached.

[[Page 15024]]

    #9. Sample(s) used in the initial demonstration must be within
the recommended holding times, where applicable.
    Unless holding time (time from when a sample is collected until
analysis) has been specifically evaluated, this entry should be
taken directly from the reference method/standard. If holding time
has been evaluated, include the study description and conclusions of
that evaluation here, with a reference to the specific study
description. The data must be attached.
    #10. Interferences.
    Enter information on any known or suspected interferences with
the performance-based method. Such interferences are difficult to
predict in many cases, but may be indicated by unacceptable spike
recoveries in environmental matrices, especially when such recovery
problems were not noted in testing a clean matrix such as reagent
water. The inferences associated with the reference method are to be
indicated, as well as, the affect of these interferences on the
performance-base method.
    #11. Qualitative identification criteria used.
    Enter all relevant criteria used for identification, including
such items as retention time, spectral wavelengths, ion abundance
ratios. If the instrumental techniques for the performance-based
method are similar to the reference method, use the reference method
as a guide when specifying identification criteria. If the list of
criteria is lengthy, attach it on a separate sheet, and enter ``see
attached'' for this item.
    #12. Performance Evaluation Studies performed for analytes of
interest, where available (last study sponsor and title:; last study
number:).
    Several EPA Programs conduct periodic performance evaluation
(PE) studies. Organizations outside of the Agency also may conduct
such studies. Enter the sponsor, title, and date of the most recent
study in which the performance-based method was applied to the
matrix of interest. For the performance-based method to be
acceptable, the performance on such studies must be ``fully
successful'', i.e., within the study QC acceptance criteria.
    #13. Analysis of external reference material.
    Enter the results of analyses on reference material from a
source different from that used to prepare calibration standards
(where applicable). This performance category is especially
important if Performance Evaluation Studies are not available for
the analytes of interest. Analysis of a reference sample is one of
standardized QC elements specified for wastewater and drinking water
methods at 40 CFR 136.4, 136.5 and 141.27. A common (and
recommended) reference sample is a Reference Material from the
National Institute of Standards and Technology.
    #14. Source of reference material.
    Enter criteria, if applicable, for traceability of materials
used to verify the accuracy of the results, e.g., obtained from the
National Institute of Science and Technology (NIST).
    #15. Surrogates used if applicable.
    Surrogates may be added to samples prior to preparation, as a
test of the entire analytical procedure. These compounds are
typically brominated, fluorinated or isotopically labeled compounds,
with structural similarities to the analytes of interest. Also, they
are not expected to be present in environmental samples. Surrogates
are often used in the analysis for organic analytes. Enter the names
of the surrogate compounds in this category.
    #16. Concentrations of surrogates (if applicable).
    Enter the concentration of surrogates once spiked into the
sample (i.e., final concentration).
    #17. Recoveries of Surrogates appropriate to the proposed use
(if applicable).
    Enter the summary of the surrogate recovery limits and attach a
detailed listing if more space is needed.
    #18. Sample Preparation.
    Enter necessary preliminary treatments necessary, e.g.,
digestion, distillation and/or extraction. A detailed listing may be
attached if more space is needed.
    #19. Clean-up Procedures.
    Enter necessary intermediatory steps necessary prior to the
determinative step (instrumental analysis), e.g., GPC, copper
sulfate, alumina/Florisil treatment, etc.
    #20. Method Blank Result.
    A clean matrix (i.e., does not contain the analytes of interest)
that is carried through the entire analytical procedure, including
all sample handling, preparation, extraction, digestion, cleanup and
instrumental procedures. The volume or weight of the blank should be
the same as that used for sample analyses. The method blank is used
to evaluate the levels of analytes that may be introduced into the
samples as a result of background contamination in the laboratory.
Enter the analyte(s) and concentration measured in the blank.
    #21. Matrix (reagent water, drinking water, soil, waste solid,
air, etc.).
    Refers to the specific sample type within the broader ``Medium''
that was spiked, e.g., for the Medium ``Hazardous Waste,'' an
example matrix spiked as part of the initial demonstration of method
performance might be ``solvent waste''. For wastewater and drinking
water methods, the term ``medium'' is replaced with ``matrix'.
    #22. Spiking System, appropriate to the method and application.
    Enter the procedure by which a known amount of analyte(s)
(``spike'') was added to the sample matrix. This may include the
solvent that is employed and the technique to be employed (e.g.,
permeation tube, or volumetric pipet delivery techniques spiked onto
a soil sample and allowed to equilibrate one day, etc.). Solid
matrices are often difficult to spike and considerable detailed
narrative may be necessary to delineate the procedure. For spikes
onto aqueous samples, generally a water miscible solvent is
specified.
    #23. Spike levels (w/units corresponding to final sample
concentration).
    Enter the amount of the analyte(s) (``spike'') that was added to
the sample matrix in terms of the final concentration in the sample
matrix. For wastewater and drinking water methods, initial spikes,
also known as initial precision and recovery (IPR) standards, will
be performed in reagent water. Using reagent water will allow the
comparison of IPR spike recoveries determined with the modified
method against IPR criteria specified in the reference method
because reference method IPR specifications are developed from
reagent water spikes.
    #24. Source of spiking material.
    Enter the organization or vendor from which the ``spiking''
material was obtained. This should include specific identification
information, e.g., lot#, catalogue number, etc.
    #25. Number of Replicate Spikes.
    The initial demonstration of method performance involves the
analyses of replicate spikes into a defined sample matrix category
#21. Enter the number of such replicates. In general, at least four
replicates should be prepared and analyzed independently.
    #26. Precision (analyte by analyte).
    Precision is a measure of agreement among individual
determinations. Statistical measures of precision include standard
deviation, relative standard deviation or percent difference.
    #27. Bias (analyte by analyte).
    Bias refers to the systematic or persistent distortion of a
measurement process which causes errors in one direction. Bias is
often measured at the ratio of the measured value to the ``true''
value or nominal value. Bias is often (erroneously) used
interchangeably with ``accuracy'', despite the fact that the two
terms are complementary, that is, high ``accuracy'' implies low
``bias'', and vice versa. Enter the name of the Bias measure (%
recovery, difference from true, etc.), the numeric value with
associated units for each analyte obtained for each analyte spiked
in the initial demonstration procedure.
    #28. Detection Limit (w/units; analyte by analyte).
    A general term for the lowest concentration at which an analyte
can be detected and identified. There are various measures of
detection which include Limit of Detection and Method Detection
Limit. Enter the detection measure (e.g., ``MDL'') and the
analytical result with units for each analyte in the matrix (#21).
For wastewater and drinking water methods MDL requirements are
specified at 40 CFR 136.4 and 141.27.
    #29. Confirmation of Detection Limit.
    In addition to spikes into the matrix of interest (#21) it may
be beneficial to perform the detection measurements in a clean
matrix, e.g., laboratory pure water. Results of the spikes in the
clean matrix are frequently available in the Agency's published
methods. Determining MDLs in a clean matrix using the performance-
based method will allow a comparison to the MDLs published in the
Agency methods.
    Also, the detection limit technique may specify specific
procedures to verify that the obtained limit is correct, e.g., the
``iterative process'' detailed in the 40 CFR part 136, Appendix B,
MDL procedures.
    #30. Quantitation Limit (w/units; analyte by analyte).
    The lowest concentration that the analyte can be reported with
sufficient certainty that

[[Page 15025]]

an unqualified numeric value is reportable. Measures of Quantitation
limits include the Minimum Level (ML), Interim Minimum Level (IML),
Practical Quantitation Level (PQL), and Limit of Quantitation (LOQ).
Enter the measure of quantitation limit, and the units for each
analyte.
    #31. Qualitative confirmation.
    Enter all relevant criteria used for identification, including
such items as: retention time; use of a second chromatographic
column; use of second (different) analytical technique; spectral
wavelengths; and ion abundance ratios. If the instrumental
techniques for the modified method are similar to those of the
reference method, use the reference method as a guide when
specifying confirmation criteria. If the list of criteria is
lengthy, attach it on a separate sheet, and enter ``see attached''
for this item.
    #32. Frequency (initial Demonstration to be performed).
    Enter the frequency that the initial demonstration has to be
repeated, e.g., with each new instrument or once a year, which ever
is more frequent.
    #33-#34. Other Criteria.
    Enter other necessary program/project specific method
performance categories. For wastewater and drinking water methods,
Categories 33 and 34 are used as follows:
    #33. Matrix Spike/Matrix Spike Duplicate.
    Enter the percent recoveries of analytes spiked into the sample
matrix. For method modifications, only one set of matrix spike/
matrix spike duplicate (MS/MSD) samples are required. For new
methods, two sets of MS/MSD samples must be analyzed to provide
sufficient data for QC acceptance criteria development.
    #34. Matrix Spike/Matrix Spike Duplicate Relative Percent
Deviation.
    Enter the calculated relative percent deviation between the MS
and MSD analyte recoveries.

Signatures:

    The name, signature and date of each analyst involved in the
initial demonstration of method performance is to be provided at the
bottom of the check sheet.

Continuing Demonstration of Capability Checklist

    The process by which a laboratory documents that their
previously established performance of an analytical procedure
continues to meet performance specifications as delineated in this
checklist.
    #1. Method Blank.
    A clean matrix (i.e., one that does not contain the analytes of
interest) that is carried through the entire analytical procedure,
including all sample handling, preparation, extraction, digestion,
cleanup and instrumental procedures. The volume or weight of the
blank should be the same as that used for sample analyses. The
method blank is used to evaluate the levels of analytes that may be
introduced into the samples as a result of background contamination
in the laboratory. Enter the analyte(s) and concentration measured
in the blank.
    #2. Concentrations of calibration standards used to verify
working range, where applicable (include units).
    The range of the concentrations of materials used to confirm the
established relationship between the response of the measurement
system and analyte concentration. This range must bracket any
action, decision or regulatory limit. In addition, this range must
include the concentration range for which sample results are
measured and reported (when samples are measured after sample
dilution/concentration). Enter the concentrations of the calibration
standards.
    #3. Calibration Verification.
    A means of confirming that the previously determined calibration
relationship still holds. This process typically involves the
analyses of two standards with concentrations which bracket the
concentrations measured in the sample(s). Enter the procedure to be
used to verify the calibration and the results obtained for each
analyte.
    #4. Calibration check standard.
    A single analytical standard introduced into the instrument as a
means of establishing that the previously determined calibration
relationship still holds. Enter the concentrations and result for
each analyte.
    #5. External QC sample (where applicable).
    Enter the results of analyses for reference material (e.g.,
Quality Control samples/ampules) from a source different from that
used to prepare calibration standards (where applicable). Enter the
concentration, as well as, the source of this material. This
performance category is of particular importance if Performance
Evaluation studies are not available for the analytes of interest.
    #6. Performance Evaluation studies performed for analytes of
interest, where available (Last study sponsor and title: Last study
number:).
    Several EPA Programs conduct periodic performance evaluation
(PE) studies. Other organizations, outside of the Agency, also
conduct such studies. Enter the sponsor, title, and date of the most
recent study in which the performance-based method was applied to
the matrix of interest. For the Performance-based method to be
acceptable the performance on such studies must be ``fully
successful'', i.e., within the study QC acceptance criteria.
    #7. List of analytes for which results were ``not acceptable''
in PE study.
    #8. Surrogate Compounds used (if applicable).
    Surrogates may be added to samples prior to preparation, as a
test of the entire analytical procedure. These compounds are
typically brominated, fluorinated or isotopically labeled compounds,
with structural similarities to the analytes of interest. They are
compounds not expected to be present in environmental samples.
Surrogates are often used in analyses for organic analytes. Enter
the names of the surrogate compounds in this performance category.
    #9. Concentration of surrogates (if applicable).
    Enter the concentration of surrogates once spiked into the
sample (i.e., final concentration), with units.
    #10. Recoveries of Surrogates appropriate to the proposed use
(if applicable).
    Enter the summary of the surrogate recovery limits and attached
a detailed listing (each surrogate compound), if more space is
needed.
    #11. Matrix (reagent water, drinking water, soil, waste solid,
air, etc.).
    Refers to the specific sample type within the broader ``Medium''
that was spiked, e.g., for the Medium ``Hazardous Waste,'' an
example matrix spiked as part of the initial demonstration of method
performance might be ``solvent waste''.
    #12. Matrix Spike Compounds.
    In preparing a matrix spike a known amount of analyte is added
to an aliquot of a real-world sample matrix. This aliquot is
analyzed to help evaluate the effects of the sample matrix on the
analytical procedure. Matrix spike results are typically used to
calculate recovery of analytes as a measure of bias for that matrix.
Enter the analytes spiked.
    #13. Matrix Spike Concentrations (w/units corresponding to final
sample concentration).
    Enter the amount of the analyte(s) (``spike'') that was added to
the sample matrix in terms of the final concentration in the sample
matrix.
    #14. Recovery of Matrix Spike (w/units).
    The ratio of the standard deviation of a series of at least
three measurements to the mean of the measurements. This value is
often expressed as a percentage of the mean.

    Note: Some programs/projects have utilized matrix spike
duplicates (a separate duplicate of the matrix spike) to help verify
the matrix spike result and to provide precision data for analytes
which are not frequently found in real-world samples, i.e.,
duplication of non-detects provides little information concerning
the precision of the method.

    #15. Qualitative identification criteria used.
    Enter all relevant criteria used for identification, including
such items as retention times, spectral wavelengths, ion abundance
ratios. If the instrumental techniques for the Performance-based
method are similar to the reference method, use the reference method
as a guide when specifying identification criteria. If the list of
criteria is lengthy, attach it on a separate sheet, and enter ``see
attached'' for this item.
    #16. Sample Preparation.
    Enter necessary preliminary treatments necessary, e.g.,
digestion, distillation and/or extraction. A detailed listing may be
attached if more space is needed.
    #17. Clean-up Procedures.
    Enter intermediatory steps necessary to prior to the
determinative step (instrumental analysis), e.g., GPC, copper
sulfate, alumina/florisil treatment, etc.
    #18. Confirmation.
    Qualitative identification criteria used. Enter all relevant
criteria used for identification, including such items as: retention
time; use of second chromatographic column; use of second
(different) analytical technique; spectral wavelengths, ion
abundance rations. If the instrumental techniques for the
Performance-based method are similar to the reference method, use
the reference method as a guide when specifying confirmation
criteria. If the

[[Page 15026]]

list of criteria is lengthy, attach it on a separate sheet, and
enter ``see attached'' for this item.
    #19-20. Other.
    Enter other necessary program/project specific method
performance categories.

Signatures:

    The name, signature and date of each analyst involved in the
continuing demonstration of method performance is to be provided at
the bottom of the checklist.

Appendix F to Part 136--Guidelines and Format for Methods to be
Proposed at 40 CFR Part 136 or Part 141

    This appendix has been prepared to promote consistency among
analytical methods and to streamline the method promulgation
process. The elements in this appendix are mandatory for all methods
proposed for approval at 40 CFR part 136 or 141. The appendix has
four sections. The first section specifies standard elements that
must be included in the method, the second section specifies the
required method format, the third section specifies conventions to
be used when preparing the method, and the fourth section specifies
the required method content.

1.0  Elements

1.1  Cover Page

    For methods submitted to EPA from other organizations or
individuals, no cover page is required. Prior to method publication,
EPA will prepare the cover page in the standard EPA format. The
cover page will use black ink on white or colored paper stock and
may include a cover graphic that illustrates the method.
    EPA will assign a three- or four-digit method number that
correlates with the EPA method series to which the method belongs.
The method number is included as the first part of the method title
on the cover page.

1.2  Title Page

    There are two types of title page: a title page prepared by an
organization or individual that is submitting a method to EPA, and
the final title page that appears in the EPA-published method.
    1.2.1  Individuals or organizations submitting methods to EPA
should include the following information on the title page of the
method: Method title, Date, and Sponsoring organization with address
and telephone number.
    1.2.1.1  When titling the method, use a concise title that cites
(in sequence) the particular analyte(s) or property being
determined, the type of sample or sample matrix(ces) to which the
method is applicable, as appropriate, and the determinative
technique or instrumentation. Apply the following guidelines in
titling methods:
    1.2.1.1.1  If the method applies to numerous matrices (such as
water, soil, sediment, sludge, tissue, and others), it may not be
practical to include matrices in the title. However, if the method
applies to a single matrix or a limited number of matrices, the
matrix(ces) should be specified in the title.
    1.2.1.1.2  If the method is used to determine a number of
analytes or properties, analytes or properties can be named as a
group (e.g., trace elements), and the names of specific analytes or
properties omitted.
    1.2.1.1.3  Avoid the use of the terms ``analysis of...'' or
``determination of...'' in method titles, since these terms are
understood within the context of the term ``method.''
    1.2.1.1.4  Method titles should use abbreviations or acronyms
for familiar parts of the method title, e.g., HRGC/HRMS. The acronym
or abbreviation should be defined at first use in the method.
Examples of suitable method titles are: ``Mercury in Water by
Oxidation, Purge and Trap, and Cold Vapor Atomic Fluorescence
Spectrometry'' and ``Tetra-through Octa-Chlorinated Dioxins and
Furans by Isotope Dilution HRGC/HRMS''.
    1.2.1.2  For a methods manual, use a title that identifies the
category of methods included in the manual. Examples of suitable
methods manual titles are: ``Analytical Methods for Pulp and Paper
Industry Wastewater'' and ``Analytical Methods for the Determination
of Pollutants in Pharmaceutical Manufacturing Industry Wastewater'.
    1.2.2  Before publishing the method, EPA will generate a title
page that mimics the cover page (excluding any cover graphics).

11.3  Acknowledgments

    Acknowledgments should identify the author and editor, and
provide credit to researchers, peer reviewers, and organizations or
individuals that contributed directly and substantively in the
development and writing of the method. These acknowledgments are
independent of references listed at the end of the method.

1.4  Disclaimer

    The disclaimer may appear on the same page with the
acknowledgments or may be on the page following the acknowledgments.
It may contain one or more disclaimer statements. All disclaimers
should include the following statement: ``The mention of trade names
or commercial products does not constitute endorsement or
recommendation for use.''
    The disclaimer may not state explicitly or imply that EPA has
granted any approval of the method. Once the method has been
validated and submitted to EPA for proposal, however, the following
statement may be included: ``This method has been submitted to the
U.S. Environmental Protection Agency for use in EPA's water programs
but has not been approved for use by EPA.''
    For draft methods, include the following statement: ``This
method is in draft form. It has not been released by the U.S.
Environmental Protection Agency and should not be construed as an
Agency-endorsed method. It is being circulated for comments on its
technical merit.''
    When preparing the method for proposal at 40 CFR part 136 or
141, EPA will edit the disclaimer to cite the Agency review process
that the method has undergone.

1.5  Table of Contents

    A table of contents is required for methods manuals and is
recommended for single methods that exceed 25 pages in length. The
table of contents should cite the titles and page numbers of all
first-and second-order headings (see section 2.9 of this appendix)
and all tables and figures.

1.6  Introduction

    In the introduction, provide background on the method, describe
the purpose of the method, and include a summary-level description
of the method. Identify the name, organization, address, and
telephone number to contact for questions regarding the method.
    When preparing the validated method for submission to EPA for
proposal at 40 CFR part 136 or 141, include the following
instructions at the end of the introduction:
    Questions concerning this method or its application should be
addressed to: W. A. Telliard, USEPA Office of Water, Analytical
Methods Staff, Mail Code 4303, 401 M Street, S.W., Washington, DC
20460, 202/260-7120.
    Requests for additional copies of this publication should be
directed to: Water Resource Center, Mail Code RC-4100, 401 M Street,
SW., Washington, DC 20460, 202/260-7786.

1.7  Notice of Performance-based Method

    All methods prepared should be performance-based and should
contain the following notice on a separate page directly preceding
the body of the method: ``Note: This method is performance-based.
The laboratory is permitted to modify or omit any step or procedure,
provided that all performance requirements set forth in this method
and in the applicable regulations at 40 CFR parts 136 and 141 are
met. The laboratory may not omit any quality control analyses. The
terms ``shall,'' ``must,'' and ``may not'' indicate steps and
procedures required for producing reliable results. The terms
``should'' and ``may'' indicate optional steps that may be modified
or omitted if the laboratory can demonstrate that the modified
method produces results equivalent or superior to results produced
by this method.''

1.8  Body of Method

    The body of the method must be presented in the EMMC format. See
Section 4.0 of this appendix for a detailed description of this
format.

2.0  Format

2.1  Page Numbering

    Page numbers should appear in the bottom center of the page. For
methods prepared double-sided, page numbers may appear on the
outside bottom corner of the page (i.e., on the bottom right for
right-hand pages and on the bottom left for left-hand pages). 2.1.1
Numbering front matter--Number the front matter (i.e., everything
preceding the body of the method) consecutively using lower-case
Roman numerals. The numerals should appear on the bottom of each
page of the front matter, except for the cover and title pages. The
cover page is unnumbered. The title page holds the place of page i,
but the numeral is not displayed.
    2.1.2  Numbering body of method--Number the body of the method
consecutively with Arabic numerals on the bottom of each page,
starting with the number 1.

[[Page 15027]]

2.2  Method Identification

    2.2.1  The method introduction page(s) should contain a header
that identifies the method number and revision number or letter. The
first page of the body of the method (preceding 1.0 Scope and
Application) should start with the method number and title in the
top center of the page with no header. Each pursuant page of the
method should contain a header that identifies the method number and
revision number or letter. The header also must be separated from
the main body of the method by a horizontal line running the width
of the page.
    2.2.2  If the method was assigned a non-EPA method number during
its development and validation, when preparing the method for
submission to EPA for proposal at 40 CFR part 136 or 141, edit the
header to reflect the method number assigned by EPA (i.e., Method
1664).

2.3  Method Date

    The date of the method (month and year) should appear on the
bottom of each page of the method.

2.4  Font

    For text, use an 11-point Times Roman font (typeface). For
first-order headings, use a bold, 14-point Univers font. For section
numbering, use a bold, 12-point Univers font. For headers and
footers, use an italics, 9-point Univers font. Univers or Times
Roman fonts may be used in tables as appropriate. If Univers is
unavailable, Helvetica may be substituted.

2.5  Margins

    Left and right margins should be one inch. The header should be
0.5 inch from the top of the page, with the text starting one inch
from the top of the page. The page number should appear 0.5 inch
from the bottom of the page, with the text starting one inch from
the bottom of the page.

2.6  Justification

    Use left justification for text. This results in a ragged-right
margin.

2.7  Line Spacing

    The method should be single-spaced. (If preferred, 1.1 line
spacing can be used to enhance readability.) One blank line should
appear between each paragraph and section.

2.8  Method Sections

    Each method must contain the sections given in the EMMC method
format. See Section 4.0 for a detailed description of this format.
If a section does not apply to a particular method, include the
section with a statement that it is not applicable to that method.

2.9  Section Headings and Numbering

    Use the Modified Decimal Numbering (MDN) system to organize
material presented in methods and methods manuals. In this system,
each method section and subsection is assigned a unique number that
shows the relationship of a specific section/subsection to all
previous sections/subsections and allows for easy reference. This
numbering system is used in this document.
    The first-order headings are the 17 sections identified in
Section 4, starting with ``1.0 Scope and Application''. First-order
headings must appear on a separate line, with a blank line appearing
between the heading and the section text. Subsections are numbered
and may or may not have a heading preceding the text. Second-order
headings or sections are numbered 1.1, 1.2, 1.3, 1.4, etc. Third-
order headings or sections are numbered 1.1.1, 1.1.2, 1.1.3, etc.
Fourth-order headings or sections are numbered 1.1.1.1, 1.1.1.2,
1.1.1.3, etc.
    Do not number beyond the fourth-order heading or section. If
additional subdivisions are necessary, use (a), (b), (c), etc. to
identify further divisions. Use of subdivisions below the fourth-
order heading or section should be avoided where possible by
organizing the material differently.

2.10  Indentation

    First-order headings should appear flush left. Each subsequent
order heading should be block-indented to align with the text of the
previous order heading. This indentation method is illustrated in
this document.

2.11  Electronic Submission

    Methods and methods manuals must be prepared and submitted to
EPA in both hardcopy and electronic formats.
    2.11.1  Hardcopy methods should be produced in black type on
white or off-white recycled paper and printed or copied double-
sided.
    2.11.2  Electronic methods must be submitted in machine-readable
format, either ASCII or Agency standard (Novell
WordPerfect 6.1 or later).
    2.11.3  To enable anyone accessing a method electronically to be
certain they have retrieved the entire section or method accessed,
include a ``section end'' notice at the end of each first-order
section. This is illustrated as follows:

2.12 References

    Use the following format for order, content, and punctuation
when listing references.
    2.12.1  Books--author's name or names (initials last), title of
book (underline, period, no quotation marks), name of publisher,
address of publisher (city and state), year of publication, and page
number, if applicable
    2.12.2  Magazines and Journals--author's name or names (initials
last), ``title of paper'' (quotation marks, comma), volume number,
issue number (this may be omitted if the journal page numbers are
continuous throughout the volume), date of publications, and page
numbers. Example: Jones, J.J., and Smith, R.R., ``Correlation of
Brinell Hardness and Tensile Strength, Materials in Design
Engineering. Vol. 10, No. 2, February 1958, pp. 52-67.
    2.12.3  Proceedings, Transactions, Reports, Bulletins, etc.--
author's name or names (initials last), ``title of paper'' (in
quotation marks), name of publication (underline, no quotation
marks, comma), name of publisher, volume number, if any date of
publication, and page numbers.
    2.12.4  Symposium Volumes or Other Books Comprising Collections
of Papers--Follow style for books, above and add title of paper, in
quotes, after author's name.
    2.12.5  Patents--patent number and data.
    2.12.6  EPA methods--Method number and name, EPA report number,
U.S. Environmental Protection Agency, laboratory and/or office,
location, date.

3.0  Conventions

3.1  Capitalization, Italics, Underlining, and Boldface

    3.1.1  Capitalization
    3.1.1.1  For first-order headings (numbered 1.0, 2.0, 3.0,
etc.), use initial capitalization of major words.
    3.1.1.2  For second-, third-, or fourth-order headings,
capitalize the first word of the heading only.
    3.1.2  Italics--Italicize words or blocks of text for emphasis.
Equations and notes interspersed in the text also should be
italicized.
    3.1.3  Underlining--Underline words that are defined in the
Definitions section (or glossary). Use underlining in tables as
appropriate for clear presentation of material. Do not use
underlining for emphasis; use italics instead but avoid overuse of
emphasis.
    3.1.4  Boldface--Boldface the following items:
    3.1.4.1  The method number and title on the cover page, title
page, and page 1 of the method.
    3.1.4.2  Acknowledgments, Disclaimer, and Introduction headings.
    3.1.4.3  First-order headings.
    3.1.4.4  Section numbering.
    3.1.4.5  Equation numbers.
    3.1.4.6  The word ``Note:'' preceding text notes.

3.2  Punctuation

    3.2.1  Always use a comma after the second to last entry in a
series.
    3.2.2  A dash may be used between a subheading and text that
directly follows the subheading. There should be no blank space
before or after the dash, e.g., ``Matrix Spikes--The laboratory must
spike...''
    3.2.3  As a general rule, use a hyphen in compound modifiers to
avoid ambiguity, e.g., 1-L flask. (In some cases, the hyphen can be
left out without ambiguity, e.g., toxic chemical waste.) Do not use
a hyphen after an adverb ending in ``ly,'' e.g., commonly accepted
practice.
    3.2.4  Bullets are not to be used in the body of the method. If
used in introductory material, the text following the bullet should
start with a capital letter. Short bullets do not require periods at
the end; long (multiple-line) bullets do. Semicolons or commas
should not be used after bulleted text.

3.3  Footnotes

    Use footnotes only in tables. Footnotes should be designated
with numbers or lower case letters in superscript, and should appear
below the body of the table.

3.4  Text Notes

    Notes may be used within the text to highlight important
information regarding use of the method. Use a margin-to-margin line
across the page both preceding and following the note to set it off
from the text.

3.5  Equations

    Equations should be numbered Equation 1, Equation 2, etc.,
consecutively as they appear in the text. Use a margin-to-margin
line across the page both preceding and following

[[Page 15028]]

the equation to set it off from the text. Equations should be
presented in italics. The equation is followed by ``where:'' and a
list of terms used in the equation (e.g., where: n = number of
samples, x = concentration in each sample).

3.6  Tables and Figures

    Tables and figures appear in Section 17.0.
    3.6.1  Number tables and figures consecutively with Arabic
numerals, and give each a title that is complete and descriptive.
    3.6.2  In table column headings, specify the quantity being
tabulated, followed by the units of measurement shown in
parentheses. For example, ``Amount spiked (g/L)''.
    3.6.3  Place table and figure titles above the information
presented.
    3.6.4  Figures may be enclosed in a box if desired.

3.7  Trademarks

    3.7.1  Avoid the use of trademarks or brand names whenever
possible. For examples, use the term ``borosilicate glass'' rather
than the trademarks Pyrex or Kimax; use ``fluoropolymer'' rather
than Teflon. (See Section 4.6.4.)
    3.7.2  When a trademark or brand name is used, capitalize it.

3.8  Text References

    Text references are references to other locations within the
method, not references to any outside source. References to other
sources appear in Section 16.0. Do not incorporate essential
information into the method by referring to another method.
    In the method text, refer to other sections of the method
capitalizing the word ``Section.'' Section references should appear
in parentheses at the end of the phrase or sentence to which the
reference applies, for example, (Section 9.6).

3.9  Units, Symbols, Abbreviations, and Acronyms

    3.9.1  Units and symbols from the international metric system
(SI, from the French name, Le Systeme International des Unites) are
to be used. SI is based on seven basic units that are dimensionally
independent. The SI unit of time is the second (symbol = s) which
should be used if practical. The SI unit of volume is the cubic
meter (symbol = m\3\) but the spectral name liter (symbol = L) can
be used for liquids and gases. Although the SI unit for mass is
kilogram (symbol = kg), the use of gram (g) with or without prefixes
is appropriate.
    3.9.2  Symbols, not abbreviations, should be used for units.
Symbols are not followed by a period except when used at the end of
a sentence. Unit symbols are written in lower case except for the
symbol for liter (L) or where the unit name was derived from a
proper name, such as Pa, from Pascal. When a quantity is expressed
as a numerical value and a unit symbol, a space should be left
between them, except between the number and symbol for degree
Celsius (e.g., 20 deg.C) and for degree, minute, and second of plane
angle.
    3.9.3  Use commonly accepted acronyms and abbreviations in text
and tables. An acronym is a word formed from the first or first few
letters of other words; everything else is an abbreviation. In many
cases, an acronym or abbreviation is more readily identifiable than
its narrative counterpart. Always spell out the term the first time
it is used and follow it with the acronym or abbreviation shown in
parentheses, e.g., material safety data sheet (MSDS), relative
percent difference (RPD), or United States Environmental Protection
Agency (EPA). Acronyms and nearly all abbreviations have no periods
or spaces between letters. As depicted in these examples, although
the acronym or abbreviation is capitalized, the narrative version of
it is not capitalized unless it is a proper name such as a
government agency, society, or association. Once an acronym or
abbreviation is introduced in this manner, use only the acronym or
abbreviation subsequently.
    3.9.4  When a long word or phrase for which there is no standard
acronym or abbreviation is used frequently, it may be replaced by an
acronym or abbreviation that is explained when it first occurs. For
example, relative centrifugal force (RCF).

3.10  Numerals

    3.10.1  Spell out single-digit numbers (one through nine), with
the following exceptions:
    3.10.1.1  Use numerals when the quantity is partly fractional,
e.g., 1.15, 1\1/2\.
    3.10.1.2  Use numerals when the number is followed by a unit
symbol, e.g., 1 m, 9%, 3 ppm. In the method text, units should be
spelled out, so the numbers one through nine associated with the
units would be spelled out also (e.g., one meter, nine percent,
three parts per million).
    3.10.1.3  Use numerals to identify equations and tables (e.g.,
Equation 2, Table 5).
    3.10.1.4  In sentences containing multiple numbers, if some
numbers must be numerals, use numerals for all (e.g., 2 tests and 16
weighings).
    3.10.2  Use numerals for multiple-digit numbers (10 and above),
with the following exceptions:
    3.10.2.1  Do not begin a sentence with a numeral. When the
numeral is spelled out, also spell out the unit following (e.g., One
gram is usually sufficient.)
    3.10.2.2  Spell out round numbers that are used in an indefinite
sense (e.g., a hundred feet or so).
    3.10.3  When a number is used as an adjective, insert a hyphen
between the number and the unit symbol (e.g., 100-mL volumetric
flask, 1-L sample).
    3.10.4  When writing decimal numbers of value less than one,
place a zero before the decimal point (e.g., 0.45 g).
    3.10.5  Do not point-off numbers of four figures (1234) except
in tables when they occur in a column containing numbers of more
than four figures. Point-off numbers of more than four figures,
using commas with no spaces (e.g., 1,325,000).
    3.10.6  In expressing ranges and ratios in text, use 1 to 10 or
1:10, not 1-10. A hyphen may be used for ranges in tables.

3.11  Significant Digits

    Handle numbers with careful regard for correspondence between
the data accuracy and the given number of digits. The number of
significant digits should neither sacrifice nor exaggerate accuracy.
    3.11.1  Any digit that is necessary to define the specific value
or quantity is significant and should be used. For example, when
measured to the nearest 1 m, a distance may be 157 m, which has
three significant figures; when measured to the nearest 0.1 m, the
distance may be 157.4 m, which has four significant figures.
    3.11.2  When adding or subtracting numbers with different
degrees of precision, the answer should contain no digits farther to
the right than the least precise number. Numbers should first be
rounded to one digit farther to the right than that of the least
precise number. The answer is then rounded to the same number of
significant figures as the least precise number.
    3.11.3  For multiplication and division, the product or quotient
should contain no more significant figures than are contained in the
number with the fewest significant figures.
    3.11.4  Examples to distinguish the addition/subtraction and
multiplication/division rules are:

Addition: 113.2+1.43=114.63, rounded to 114.6
Subtraction: 113.1-1.43=111.77, rounded to 111.8
Multiplication: 113.2 x 1.43=161.876, rounded to 162
Division: 113.11.43=79.16, rounded to 79.2

    Note: The product and quotient above should contain only three
significant figures because the number 1.43 contains only three
significant figures. The above sum and difference, however, contain
four significant figures, because digits that occur to the right of
the last significant in the least precise number are rounded.

3.12  Order of Magnitude

    Zeros may be used to indicate a specific value or to indicate
the order of magnitude of a number. For example, in the number
203,185,000, representing population rounded to thousands, the first
six digits are significant. The last three digits are zeros that
indicate the order of magnitude.

3.13  Rounding

    3.13.1  When the first digit discarded is less than five, the
last digit retained is not changed.
    3.13.2  When the first digit discarded is five or greater, or
when five is followed by a digit other than zero, the last digit
retained is increased by one.
    3.13.3  When the first digit discarded is exactly five followed
only by zeros, the last digit retained is rounded upward if it is an
odd number and is not adjusted if it is an even number.

4.0  Content

    In accordance with EMMC format, each analytical method must
contain 17 specific topical sections in a designated order. The
required order and content of these sections are listed and
described below. All of these sections are mandatory for all
methods.

1.0  Scope and Application
2.0  Summary of Method
3.0  Definitions
4.0  Interferences

[[Page 15029]]

5.0  Safety
6.0  Equipment and Supplies
7.0  Reagents and Standards
8.0  Sample Collection Preservation and Storage
9.0  Quality Control
10.0  Calibration and Standardization
11.0  Procedure
12.0  Data Analysis and Calculations
13.0  Method Performance
14.0  Pollution Prevention
15.0  Waste Management
16.0  References
17.0  Tables, Diagrams, Flowcharts, and Validation Data
    Starting with section 11.0 Procedure, additional numbered
sections may be inserted as required by the particular method;
however, the sections listed above must appear in each method in the
order listed.

    Note: Subsections within each of the 17 required sections do not
need to correlate directly to the subsections included here. In
other words, the information mentioned in 4.1.1 below might be
covered in two or more subsections in a method.

4.1  Scope and Application

    This section outlines the purpose, range, limitations, and
intended use of the method, and identifies target analytes.
    4.1.1  Define the purpose and intended use of the method. State
what the method is based upon, noting any relationship of the method
to other existing analytical methods. Indicate whether the method is
associated with a sampling method. Include the following statement:
``This method is for use in the Environmental Protection Agency's
(EPA's) data gathering and monitoring programs under the Clean Water
Act, the Resource Conservation and Recovery Act, the Comprehensive
Environmental Response, Compensation, and Liability Act, and the
Safe Drinking Water Act.''
    4.1.2  List analytes that can be measured by the method,
including each analyte's Chemical Abstracts Service Registry Number
(CASRN). If regulations cite other than the most commonly used
analyte name, refer to the regulation. For pesticides, use
``acceptable common names.'' The use of registered trade names is
permitted.
    4.1.3  Identify the matrix(ces) for which the method has been
found satisfactory.
    4.1.4  Indicate the statistically determined method detection
limit (MDL) and the analyte concentration range over which the
method is applicable. State the matrix(ces) in which MDL was
determined. If the MDL is not available, report an instrumental
detection limit and define how it was derived. Indicate the minimum
level (ML) and water quality criteria if appropriate to the analyte
and method.
    4.1.5  Describe method limitations, such as ``This method is not
applicable to saline water,'' or ``This method is not intended for
determination of metals at concentrations normally found in treated
and untreated discharges from industrial facilities.'' Indicate any
means of recognizing cases where the method may not be applicable to
the sample under test.
    4.1.6  List any restrictions that may apply, such as ``This
method is restricted to use by or under the supervision of analysts
experienced in * * *''
    4.1.7  Include the following statement regarding performance-
based methods: ``This method is performance-based. The laboratory is
permitted to omit any step or modify any procedure (e.g., to
overcome interferences, to lower the cost of measurements), provided
that all performance requirements in this method are met.
Requirements for establishing method equivalency are given in
Section 9.1.2.''
    4.1.8  Include the following statement: ``Each laboratory that
uses this method must demonstrate the ability to generate acceptable
results using the procedure in section 9.1.2.''

4.2  Summary of Method

    This section provides an overview of the method procedure and
quality assurance.
    4.2.1  Outline, specifying amounts of sample and reagent, the
procedure that is followed to determine the presence or absence of
the listed analytes. Include any sample pretreatment, such as
filtration or digestion. In this description, identify the basic
steps involved in performing the method, but omit the details that
are a necessary part of the complete statement of procedure.
    4.2.1.1  For chemical methods, state the type of procedure
(colorimetric, electrometric, volumetric, etc.) and describe the
source of color, major chemical reaction, including pertinent
chemical equations, etc. For instrumental methods, state the
technique.
    4.2.1.2  In the ``Summary of Method'' section, use the passive
voice, e.g., ``Instrumental drift is corrected by using internal
standardization,'' rather than ``Correct instrumental drift by using
internal standardization.''
    4.2.2  Identify the determinative step in the method.
    4.2.3  State in a summary fashion how quality is assured in the
method.
    4.2.4  List options to the method, if applicable.

4.3  Definitions

    This section includes definitions of terms, acronyms, and
abbreviations used in the method. If preferred, definitions may be
provided in a glossary at the end of the method or manual. In this
case, the definitions section must still appear in the method, with
a notation that definitions are provided in a glossary at the end of
the method. Refer to the specific section number of the glossary.
    4.3.1  Include an introductory statement as follows: ``The
definitions and purposes below are specific to this method, but have
been conformed to common usage as much as possible.''
    4.3.2  List units of weight and measure and their abbreviations
or acronyms used in the method.
    4.3.3  Alphabetically list and define terms, acronyms, and
abbreviations used in the method. Where appropriate, include the
purpose (e.g., the purpose of the field blank is to determine if the
field or sample transporting procedures and environments have
contaminated the sample).
    4.3.4  Include definitions of the terms may, may not, must, and
should, as follows:
    4.3.4.1  May: This action, activity, or procedural step is
neither required nor prohibited.
    4.3.4.2  May not: This action, activity, or procedural step is
prohibited.
    4.3.4.3  Must: This action, activity, or procedural step is
required.
    4.3.4.4  Shall: This action, activity, or procedural step is
required.
    4.3.4.5  Should: This action, activity, or procedural step is
suggested but not required.

4.4  Interferences

    This section identifies known or potential interferences that
may occur during use of the method, and describes ways to reduce or
eliminate interferences.
    4.4.1  Describe any known or potential problem(s) (e.g., sample
or equipment contamination, instrument noise) that may be
encountered during the performance of the method and the source of
the problem(s). Recommend techniques to avoid or minimize the
problem(s) (e.g., ways to reduce sample or equipment contamination,
or instrument noise).
    4.4.2  Identify any substances, ions, or properties that are
known to or likely to cause interference and the amounts that are
known to or likely to interfere. Sometimes this information can be
obtained only by observation during the analysis. In such cases,
include appropriate notes under ``Procedure'' or ``Data Analysis and
Calculations.''

4.5  Safety

    This section describes special precautions needed to ensure
personnel safety during the performance of the method. Procedures
described here should be limited to those which are above and beyond
good laboratory practices. The section must contain information
regarding specific toxicity of analytes or reagents.
    4.5.1  Identify and warn analysts of potential hazards
associated with using the method (e.g., toxicity or carcinogenicity
of analytes or reagents, explosions, fire, radiation). Recommend
techniques to minimize hazards where possible (e.g., performing
operations in a hood or glove box).
    4.5.2  Where the toxicity or carcinogenicity of each compound or
reagent has not been precisely determined, include the following
statement: ``The toxicity or carcinogenicity of each analyte or
reagent has not been precisely determined; however, each chemical
should be treated as a potential health hazard. Exposure to these
chemicals should be reduced to the lowest possible level. It is
suggested that the laboratory perform personal hygiene monitoring of
each analyst using this method and that the results of this
monitoring be made available to the analyst.''
    4.5.3  Indicate the steps in the procedure at which hazards that
could damage equipment may occur by use of the word CAUTION in
boldface type, followed by the details of the precautionary measures
that must be taken. If any step in the procedure could result in
personal injury or death, include the word WARNING in boldface type,
followed by the details of the protective measures that must be
taken.

[[Page 15030]]

    4.5.4  Include the following statements: ``This method does not
address all safety issues associated with its use. The laboratory is
responsible for maintaining a safe work environment and a current
awareness file of OSHA regulations regarding the safe handling of
the chemicals specified in this method. A reference file of material
safety data sheets (MSDSs) should be available to all personnel
involved in these analyses. Additional information on laboratory
safety can be found in References ______.''

4.6  Equipment and Supplies

    This section lists and describes all nonconsumable supplies and
equipment needed to perform the method.
    4.6.1  Include the following statement as a note preceding the
list of equipment and supplies:

    ``Note: Brand names, suppliers, and part numbers are cited for
illustrative purposes only. No endorsement is implied. Equivalent
performance may be achieved using equipment and materials other than
those specified here, but demonstration of equivalent performance
that meets the requirements of this method is the responsibility of
the laboratory.''

    4.6.2  Categorize and list required equipment and supplies by
the logical order of use; e.g., sampling equipment, equipment for
glassware cleaning, equipment for calibration, equipment for sample
extraction, etc. Do not list common laboratory equipment, but do
include special or modified forms of unusual sizes or numbers of
common equipment that are required or that may require special
preparation.
    4.6.3  Describe the essential features of each required item.
Include schematic drawings as needed to clarify or supplement
apparatus descriptions.
    4.6.4  Avoid the use of trademarks, brand names, trade names, or
suppliers unless a specific manufacturer's product is required for a
well-defined reason or the availability of the product is limited
(i.e., the apparatus is unique or unusual). For example, when
special types of glassware are required, such as heat-resistant,
chemical-resistant, etc., state the significant characteristic
desired rather than a trademark (''borosilicate glass'' rather than
Pyrex or Kimax). If only a single source is known, that supplier may
be identified.
    4.6.5  Whenever a brand name is used, include ``or equivalent''
following the brand name or part number to demonstrate that use of
another product is acceptable.
    4.6.6  Include any special glassware cleaning instructions.
    4.6.7  List special facilities required, such as a special room
for handling hazardous materials.

4.7  Reagents and Standards

    This section lists and describes all reagents and standards
required to perform the method, and provides preparation
instructions and/or suggested suppliers as appropriate.
    4.7.1  List the name of the reagent and the necessary purity,
followed by any descriptive terms. List reagents in a logical order
(e.g., by order of occurrence or use, by group). The method should
require that reagents be ACS Reagent Grade unless otherwise
specified.
    4.7.2  Spell out the full name of inorganic reagents when first
used, and include within parentheses the exact chemical formula,
showing its water of crystallization, etc. Subsequently, refer to
inorganic compounds by formula if they can be specified clearly in
this way. As exceptions, always spell out the word ``water'' and the
names of substances in their elemental state (e.g., ``lead'' not
``Pb,'' ``oxygen'' not ``02'').
    4.7.3  Spell out organic, organometallic, or complex inorganic
compounds; chemical formulae are not necessary. Cite the CASRN to
avoid ambiguity.
    4.7.4  Avoid the use of trademarks and names of patented
products. Use chemical names and common names, unless a specific
product is required for a well-defined reason. The use of registered
trade names is permitted.
    4.7.5  Unique and unusual reagents can be named by brand.
Whenever a brand name is used, include ``or equivalent'' following
the brand name to demonstrate that another product can be used.
    4.7.6  Specify the concentration of inorganic reagents in
applicable terms, as follows:

Concentrated acids and bases: density
Dilute acids and bases: volume ratio, x+y (x volume of reagent added
to y volume by water)
Nonstandardized solutions: normality, expressed decimally; or the
equivalent of 1 mL of solution in terms of grams of a given element
expressed as 1 mL = x.xx g of * * *

    4.7.7  Specify filter paper by describing the significant
characteristic such as porosity, rate of filtering ash content,
etc., or by reference to ASTM Specification D1100 for Filter Paper
for Use in Chemical Analysis.

4.8  Sample Collection, Preservation, and Storage

    This section provides requirements and instructions for
collecting, preserving, and storing samples.
    4.8.1  Give detailed directions for collecting, filtering (if
applicable), preserving, shipping, and storing samples.
    4.8.2  Use preservation procedures and holding times consistent
with those specified in current EPA publications or regulations and
with other methods for the same analytes.

4.9  Quality Control

    This section cites the procedures and analyses required to fully
document the quality of data generated by the method. The required
components of the laboratory's quality assurance (QA) program and
specific quality control (QC) analyses are described in this
section. For each QC analysis, the complete analytical procedure,
the frequency of required analyses, and interpretation of results
are specified.

    Note: To ensure data quality, water methods must specify a
comprehensive laboratory QA program. The minimum QC requirements
that must be included in methods proposed at 40 CFR part 136 or part
141 are specified at 40 CFR 136.3 table IF, 136.4, 136.5 and 141.27.
The method should specify QC acceptance criteria.

    4.9.1  Include the following statements in the first subsection
(Section 9.1): ``Each laboratory that uses this method is required
to operate a formal quality assurance program (Reference ______).
The minimum requirements of this program consist of an initial
demonstration of laboratory capability, ongoing analyses of
standards and blanks as a test of continued performance, and
[complete as appropriate to the method]. Laboratory performance is
compared to established performance criteria to determine if the
results of analyses meet the performance characteristics of the
method.''
    ``The analyst shall make an initial demonstration of the ability
to generate acceptable accuracy and precision with this method. This
ability is established as described in Section 9.2.''
    4.9.2  In Section 9.1, cite any options that the analyst is
permitted, e.g., alternate extraction, concentration, or cleanup
procedures; changes in columns or detectors. Specify that the
analyst is required to repeat the required initial demonstration of
laboratory capability each time a modification is made to the
method. Include the following statements: ``Each time a modification
is made to the method, the analyst is required to repeat the
procedure in section 9.2. If the change will affect the detection
limit of the method, the laboratory is required to demonstrate that
the MDL (40 CFR part 136, Appendix B) is lower than the MDL for that
analyte in this method, or one-third the regulatory compliance
level, whichever is higher. If the change will affect calibration,
the analyst must recalibrate the instrument according to section
10.'';
    ``Changes that degrade method performance are not allowed. If an
analytical technique other than the techniques specified in this
method is used, that technique must have a specificity equal to or
better than the specificity of the techniques in this method for the
analytes of interest.''; and
    ``The laboratory is required to maintain records of
modifications made to this method. These records include the
following, at a minimum:

--The names, titles, addresses, and telephone numbers of the
analyst(s) who performed the analyses and modification, and of the
quality control officer who witnessed and will verify the analyses
and modification.
--A listing of analytes measured, by name and CASRN.
--A narrative stating reason(s) for the modification(s).
--Results from all QC tests comparing the modified method to this
method, including:

(a) Calibration (section 10)
(b) Calibration verification (section 9.5)
(c) Initial precision and recovery (section 9.2.2)
(d) Analysis of blanks (section 9.4)
(e) Accuracy assessment (section 9.3)
(f) Ongoing precision and recovery (section 9.6)
--Data that will allow an independent reviewer to validate each
determination by tracing the instrument output (weight or

[[Page 15031]]

other signal) to the final result. These data are to include:
(a) Sample numbers and other identifiers
(b) Extraction dates
(c) Analysis dates and times
(d) Analysis sequence/run chronology
(e) Sample weight or volume
(f) Extract volume
(g) Make and model of analytical balance and weights traceable to
NIST
(h) Copies of logbooks, printer tapes, and other recordings of raw
data
(i) Data system outputs, and other data to link the raw data to the
results reported

    4.9.3  In the remainder of section 9.1, outline the QC
requirements that will be described in the section, and the purpose
for each type of QC (e.g., blanks, matrix spikes/matrix spike
duplicates, calibration verification).
    4.9.4  In section 9.2, describe in detail the initial
demonstration of laboratory capability.
    4.9.5  Describe the procedure for matrix spikes, calculating
percent recoveries, and calculating relative percent difference for
duplicates.
    4.9.6  Provide instructions for analysis of blanks, e.g.,
laboratory reagent blanks, method blanks.
    4.9.7  Specify requirements for calibration verification.
    4.9.8  Provide instructions for analysis of ongoing precision
and recovery standards.
    4.9.9  Include requirements for analysis of quality control
samples (QCS).
    4.9.10  Include the following statement at the end of section
9.0: ``Depending upon specific program requirements, field
replicates and field spikes of the analytes of interest into samples
may be required to assess the precision and accuracy of the sampling
and sample transporting techniques.''
    4.10  Calibration and Standardization
    This section describes the method/instrument calibration and
standardization process, and required calibration verification.
Corrective actions are described for cases when performance
specifications are not met.
    4.10.1  Specify operating conditions or refer to manufacturer's
recommended operating conditions. If appropriate, specify a
precalibration routine as needed to document instrument stability.
    4.10.2  Give detailed instructions for the use of standards to
prepare calibration lines or tables. Include the number of
calibration standards, the need for blanks, the frequency of
calibration checks, the critical range, etc.
    4.10.3  Give detailed instructions for internal standardization,
including number and concentration of internal standards.
    4.10.4  Include instructions for calibration data storage.

4.11  Procedure

    This section describes the sample processing and instrumental
analysis steps of the method, and provides detailed instructions to
analysts.
    4.11.1  For methods used for determination of a method-defined
analyte, include the following statement in the introductory portion
of Section 11.0 Procedure: ``This method is entirely empirical.
Acceptable results can be obtained only by strict adherence to all
details.'' Do not include this statement in methods for which the
analyte is a chemical or physical parameter, the characteristics of
which are known (e.g., oil and grease, COD, BOD).
    4.11.2  Include in proper sequence detailed directions for
performing the analysis.
    4.11.2.1  Include steps that are essential to the process and
avoid unnecessarily restrictive instructions.
    4.11.2.2  Organize the procedure by logical order of activity,
e.g., sample preparation, extraction, analysis.
    4.11.2.3  Describe the procedure in the imperative mood, present
tense, e.g., ``Heat the sample aliquot,'' rather than ``The sample
aliquot should be heated.'' Comments and descriptive information
that are not in the imperative mood may be included, as appropriate.
    4.11.2.4  Write the text so that it is concise and easily
understandable.
    4.11.2.5  When alternative procedures are given, state which is
preferred.
    4.11.3  In chemical methods, specify the size of sample aliquot
and indicate the required measurement accuracy. (There is no need to
weigh a sample to five significant figures in a spectrophotometric
method where the final absorbance measurement yields data with only
three significant figures).
    4.11.4  Include ``Notes'' throughout the procedure to highlight
critical points. Include notes of ``WARNING'' or ``CAUTION'' as
appropriate to identify known or potential hazards to the analyst or
the equipment, respectively.
    4.11.5  Indicate steps in which timing is critical, e.g., if a
determination may not be interrupted overnight. For a color
reaction, indicate how long the color is stable.

4.12  Data Analysis and Calculations

    This section provides instructions for analyzing data, and
equations and definitions of constants used to calculate final
sample analysis results.
    4.12.1  Calculations--Provide directions for calculating the
results of the analysis, including any equations.
    4.12.1.1  Use the imperative mood, e.g., ``Report results to
three significant figures,'' rather than ``Results should be
reported to three significant figures.''
    4.12.1.2  Where there may be ambiguity of meaning, spell out
names in the text (e.g., total Kjeldahl nitrogen) but use the
abbreviations (e.g., TKN) in text where the meaning is clear, and in
equations.
    4.12.1.3  Define the symbols used in the equation immediately
under the equation.
    4.12.1.4  Use numerical values for any constants. Identify
dilution factors, titration factors, etc.

4.12.2  Reporting Results

    4.12.2.1  Indicate the units in which the results are to be
reported (e.g., g/L, mg/kg).
    4.12.2.2  If the sample is a solid material such as a sediment
or sludge, indicate whether results are to be reported as wet weight
or dry weight.
    4.12.2.3  Specify the number of significant figures to be
reported.
    4.12.2.4  Require that all values obtained by various QC
procedures are reported along with the calculated results of the
analysis.
    4.12.3  Interpretation of results--Use this heading in place of
Calculations when the results of the analysis must be expressed in
descriptive form, relative terms, or abstract values. List and
define the descriptive terms or classifications used.

4.13  Method Performance

    This section provides method performance criteria for the
method, including precision/bias statements regarding detection
limits and source/limitations of data produced using the method.

    Note: Requirements for validating new methods are specified in
[cite the volume and page number of the Federal Register in which
the streamlining initiative is promulgated].

    4.13.1  Explain how the method was validated. Provide a detailed
description of method performance, including data on precision,
bias, detection limits (including the method by which they were
determined and matrices to which they apply), and statistical
procedures used to develop performance specifications.

    Note: This information can be provided through reference to the
method validation study.

    4.13.2  At a minimum, state single-operator precision and
accuracy on reagent water. If other sample types have been
investigated, also provide this information for them.
    4.13.3  If a collaborative study has been completed, describe
the study and report the number of participating operators and
laboratories, spike concentrations, level of replication, types of
background waters, and any other significant aspects. If the study
has been documented, cite the study report and include it in the
References section. When citing reference documentation, the details
of the study do not have to be included in this section.

4.14  Pollution Prevention

    This section describes aspects of the method that minimize or
prevent pollution known to be or potentially attributable to the
method.
    4.14.1  Cite potential sources of pollution attributable to the
method.
    4.14.2  Recommend ways to minimize pollution.

4.15  Waste Management

    This section describes minimization and proper disposal of waste
and samples.
    4.15.1  Include the following statement as the first subsection:
``It is the laboratory's responsibility to comply with all federal,
state, and local regulations governing waste management,
particularly the hazardous waste identification rules and land
disposal restrictions, and to protect the air, water, and land by
minimizing and controlling all releases from fume hoods and bench
operations. Compliance with all sewage discharge permits and
regulations is also required.''
    4.15.2  Provide instructions for sample and waste handling and
disposal.

[[Page 15032]]

    4.15.3  Include the following statement as the last subsection:
``For further information on waste management, consult The Waste
Management Manual for Laboratory Personnel and Less is Better:
Laboratory Chemical Management for Waste Reduction, both available
from the American Chemical Society's Department of Government
Relations and Science Policy, 1155 16th Street NW., Washington DC,
20036.''

4.16  References

    This section lists references for source documents and
publications that contain ancillary information.

    Note: Each method should be a free-standing document, providing
all information necessary for the method user to perform the method
may be found. References within a method should be restricted to
associated or source material. Procedural steps or instructions
should not be referenced as being found elsewhere, but should be
included in total within the method.

    4.16.1  Include references for other, related EPA methods; and
published studies/articles relating to method performance,
techniques, or analytes, and health and safety.
    4.16.2  List references in the order cited in the method, and
assign each reference an identification number using Arabic
numerals.
    4.16.3  As a rule, do not list documents that are not readily
accessible to the reader (e.g., unpublished theses, personal
communications, private correspondence). If it is important to list
these types of documents, identify where the reader may obtain a
copy of the document.

4.17  Tables, Diagrams, Flowcharts, and Validation Data

    This section contains all method tables and figures (diagrams
and flowcharts), and may contain validation data referenced in the
body of the method.
    4.17.1  In addition to tables and figures, include additional
useful information. Examples of such information include:
    4.17.1.1  Notes on significance and interpretation of the
method, used to amplify the statement in the text.
    4.17.1.2  Development of equations used in the calculations.
    4.17.1.3  Charts or supplementary information for computations.

4.18  Glossary

    This optional section contains a glossary of terms, acronyms,
abbreviations, and symbols used in the method.

    Note: This information may appear in the Definitions section of
the method (Section 3.0) or may be included in a glossary at the end
of the method.

    4.18.1  In the first subsection of the glossary, identify units
of weight and measure used in the method and their abbreviations.
    4.18.2  In the second subsection, define key terms and all
acronyms used in the method.
    4.18.2.1  List terms, acronyms, and abbreviations
alphabetically.
    4.18.2.2  Definitions should appear only once. Where an acronym
or abbreviation represents a term that is defined under its full
name, reference the full name as the definition for acronym or
abbreviation.

Appendix G to Part 136--Method Flexibility, Equivalency and
Approval

    Section 1 of this appendix defines the analyst's flexibility to
modify certain steps in a reference method. Section 2 specifies
requirements for assessing the equivalency of a method modification.
Section 3 specifies requirements for submitting method modifications
or new methods for approval.

1.0  Method Flexibility

    This section specifies requirements for exercising method
flexibility (i.e., ``allowable'' method modifications). Under
requirements specified at 40 CFR 136.4 and 141.27(b), an analyst is
allowed to modify a reference method without seeking formal approval
through the regulatory process provided the modification is not
explicitly forbidden in the reference method and provided the
analyst demonstrates and documents that the modified method produces
results that are equal or superior to results produced by the
reference method. An EPA-designated reference method that contains
(or is supplemented with) QC acceptance criteria against which to
measure performance of a method modification is the primary control
used to ensure data quality. Other controls include specific multi-
laboratory and multi-matrix requirements for validating modified
methods (as specified at 40 CFR 136.4, 136.5(d), 141.27 (b) and (e))
checklists for documenting equivalency (as specified at Appendix E
of this part).
    The QC elements and associated QC acceptance criteria (e.g.,
calibration, sensitivity, accuracy, precision) necessary to
demonstrate the equivalency of a modified method to a reference
method are defined at 40 CFR 136.2 and 141.2 and specified at 40 CFR
136.3 Table IF, 136.4, 141.27 (b) and (d).

1.1  Types of Method Modifications

    There are two types of method modifications:
    1.1.1  Explicit modifications to approved methods may be made as
explicitly specified within those methods. Explicit flexibility
exists for all approved methods including EPA, Standard Methods,
ASTM, AOAC-International, and other methods approved at 40 CFR parts
136 and 141.
    1.1.2  Allowable modifications beyond those explicitly allowed
in an approved method that has been designated as a reference method
are allowed provided that the modification meets the requirements
specified in this appendix, at 40 CFR 136.4, 136.5(d) or 141.27(b)
and (e), and at Appendixes E, F, and G of this part. Allowable
modifications do not apply to Standard Methods, ASTM, and AOAC-
International methods, none of which have been designated as
reference methods.

1.2  Controls on Allowable Modifications (Method Flexibility)

    The controls on method flexibility are:
    1.2.1  A requirement to demonstrate and document equivalency
when method modifications are used.
    1.2.2  Designation of a reference method that contains (or is
supplemented with) QC acceptance criteria for use in demonstrating
equivalency.
    1.2.3  Standard procedures for validating new methods and
demonstrating equivalency of method modifications, based on the
intended use of the method.
    1.2.4  Detailed requirements for preparing the method validation
package and supporting data when new or modified methods are
validated.
    1.2.5  Requirements for assessing equivalency of method
modifications.

1.3  Reference Method

    All methods approved for use at 40 CFR parts 136 and 141 have
been categorized as either a ``reference method'' or an ``other
approved method''; both types of methods carry equal regulatory
status. The difference between the methods is that the reference
method contains (or is supplemented with) detailed QC acceptance
criteria that are required to assess the equivalency of an allowable
method modification.
    A reference method is specified at 40 CFR 136.3, 141.23(k),
141.24(e) and 141.40(n). For some determinative techniques, no
currently approved method contains either all of the QC acceptance
criteria proposed in today's rule (e.g., Table ID in 40 CFR part
136) or sufficient data from which to develop such criteria. In
these cases, no reference method has been designated; therefore, all
of these methods are classified as other approved methods. Without a
reference method, analysts are not allowed to modify approved
methods that use that determinative technique.
    Only one reference method is designated for each unique
combination of analyte and determinative technique to avoid the
possible confusion if two or more reference methods contained
different QC acceptance criteria. The QC acceptance criteria
associated with the reference method are the sole criteria against
which a method modification is tested.

1.4  Categories of Allowable Method Modifications

    The four categories of allowable method modifications are (1)
sample collection and holding procedures, (2) front-end techniques,
(3) determinative techniques, and (4) analyte addition. These
categories are defined below and described in terms of allowed
flexibility to modify the procedures or techniques included in each
category.
    The first category, sample collection and holding procedures,
includes procedures and reagents used in the field, in transit, and
at the laboratory. This category includes sample containers, sample
holding times, preservation reagents and procedures, and shipping
and storage procedures and conditions. Requirements for modifying
sample collection and preservation conditions are specified at 40
CFR 136.3(c) and 141.27(b).
    Front-end techniques, the second category of method
modifications, include any step in the analytical process used at
the laboratory that precedes the determinative technique and
includes all procedures, equipment, solvents, etc., that are used to
prepare a sample for analysis. The third category is the
determinative technique, which is defined as

[[Page 15033]]

the physical and/or chemical process by which an analyte is
identified and its concentration measured. For most methods, the
determinative technique consists of an instrumental measurement
(e.g., a detector). The fourth category covers increasing the
analytical scope of a reference method to include additional
analytes.
    A person may modify any and all front-end techniques in the
reference method, provided the modification is not explicitly
prohibited in the reference method and provided the analyst
demonstrates and documents that the modification produces results
equal or superior to results produced by the reference method. The
person must keep on file the documents that demonstrate equivalency.
Method developers are cautioned that modifications to the front-end
chemistry of the method (e.g., extraction solvents, solvent-to-
sample volumes, extraction media, and pH) require a thorough
understanding of the measurement science that was used to develop
and validate the reference method. The developer of a modified
method may ask EPA or another regulatory authority for a technical
opinion on the acceptability of the validation data that supports
the method modification(s).
    A reference method may be modified to allow use of an alternate
determinative technique that is not explicitly prohibited in the
reference method, provided that equivalency with the reference
method performance is demonstrated and documented, and provided that
four conditions are met: (1) the alternate determinative technique
must measure a property similar to the prescribed technique, (2) the
alternate technique must be demonstrated to be more specific (i.e.,
provides better separation of the analyte from interferences) and/or
more sensitive (i.e., produces a lower detection limit) for the
analyte of concern than the determinative technique in the reference
method, (3) there is not another approved method that uses the
alternate determinative technique for the determination of that
analyte, and (4) use of the alternate determinative technique would
not result in a nonsensical combination of analyte, front-end
technique, and determinative technique.
    Examples of allowed changes to a determinative technique are
substitution of a photoionization detector for a flame ionization
detector for determination of polynuclear aromatic hydrocarbons,
substitution of a nitrogen-phosphorous detector for an electron
capture detector (ECD) for determination of analytes containing
nitrogen or phosphorous, and substitution of a fluorescence detector
for an ultraviolet or visible wavelength detector. Substitution of a
mass spectrometer (MS) for an ECD would not be allowed if there is
an approved MS method that measures the analyte of concern.
    Modifications to the determinative technique are limited by the
four conditions described above to preclude nonsensical combinations
of analyte and determinative technique, to encourage a net benefit
(increased sensitivity and/or specificity), and to preclude multiple
reference methods with the same determinative technique but with
different QC acceptance criteria for the same analyte(s) of concern.
For example, if a mass spectrometer were substituted for the
conventional detectors in EPA Methods 601--612, all of these methods
would become GC/MS methods, but all would contain different QC
acceptance criteria. Further, they would all conflict with approved
EPA GC/MS Methods 625 and 1625. Another reason for limiting changes
to the determinative technique is that there are techniques, such as
immunoassay, for which EPA has no reference method and therefore no
history to ensure that the standardized QC proposed in today's rule
would be germane to, or adequate for, assurance of the quality of
data produced by the novel determinative technique. A new method
must be written and submitted to EPA for approval when a novel
determinative technique is developed.
    An analyst may add a new target analyte to a reference method
provided (1) it is demonstrated that the analyte does not interfere
with determination of the analytes of concern in that method, (2) QC
acceptance criteria are developed and employed for determination of
the target analyte, (3) there is not another approved method that
uses the same determinative technique for that analyte, and (4) that
the reason for adding the analyte is not to avoid the sample
preservation or sample (or extract) holding time conditions that are
already required for that analyte in another approved method. The
third and fourth conditions preclude ``method shopping'', whereby an
analyst might add analytes to a reference method with less rigid QC
acceptance, sample collection, or holding time criteria. Thus, if a
reference method for an analyte of concern required acidification of
the sample, an analyst does not have the flexibility to modify a
method that does not require sample acidification to include
analysis of the analyte of concern. Modifications of this type
require EPA approval as a new method.
    If QC acceptance criteria do not exist to allow addition of a
new analyte, the requirements specified at 40 CFR part 136 Appendix
E, and at 40 CFR 136.4, 136.5, and 141.27 must be used to develop
and obtain approval for these criteria. Alternatively, QC acceptance
criteria for the new analyte could be transferred from the criteria
for an analyte with similar chemical characteristics in the same
method or from the criteria for the analyte in another approved
method.

1.5  Method-Defined Analytes

    Some techniques may not produce results equivalent to results
produced by techniques employed for ``method-defined analytes''. A
method-defined analyte is an analyte that does not have a specific,
known composition so that the analytical result depends totally on
how the measurement is made. Therefore, a change to either the
front-end steps or the determinative technique for a method-defined
analyte has the potential of changing the numerical value of the
result for a given sample. Examples of method-defined analytes
include adsorbable organic halides (AOX), biochemical oxygen demand
(BOD), total radioactivity, and whole effluent toxicity (WET).
    Until the nature and extent of allowable flexibility for method-
defined analytes is defined by EPA, these methods may not be
modified using the requirements specified in this section unless the
modified method is reviewed and approved by EPA. A person may
attempt to demonstrate that the new technique produces results that
are equivalent to the reference method on a matrix-by-matrix basis.
When these data are submitted to EPA, EPA will work with the method
developer to determine whether the submitted combination of analyte
and determinative technique is new and whether a new method for a
method-defined analyte is desirable.

1.6  New Methods, Screening Methods, and Modified Methods This section
method? If not, which QC elements should be added? On the other hand,
requirements that pertain to each. This section also describes how
screening methods might be approved in the future for compliance
monitoring under the CWA and the SDWA.

    A new method is a set of procedures that:
    (1) Is documented in accordance with the requirements detailed
as specified at Appendix F of this part,
    (2) Contains the standardized QC elements defined at 40 CFR
136.2 and 141.2,
    (3) Contains QC acceptance criteria that have been developed in
accordance with the requirements at 40 CFR 136.5 and 141.27(c),
    (4) Employs a determinative technique for an analyte of concern
that differs from determinative techniques employed for that analyte
in methods previously approved at 40 CFR part 136 or 141, and
    (5) Employs a determinative technique that is more sensitive
and/or selective (specific) than the determinative techniques in all
methods previously approved for the analyte.
    Methods that meet all five of these characteristics are
considered to be definitive methods, if the method also is
sufficiently selective and quantitative that most positive results
do not have to be verified by analysis with another method. The term
``definitive'' is used to distinguish these methods from screening
methods. All methods currently approved at 40 CFR parts 136 and 141
are definitive methods.
    In this appendix, a screening method is defined as a method that
meets the first four of the five conditions described above for new
methods and that has been demonstrated to produce a false negative
probability of no more than one percent (1%) at the limit(s) of
regulatory concern. Methods can fail the fifth condition for a new
method, if they are non-selective or not quantitative for the target
analyte. A non-selective method is a method in which the
determinative (or other step) technique in the method may produce a
result for any one of several analytes that share common physical or
chemical characteristics with the target analyte. For example, an
atrazine immunoassay might respond to any triazine (atrazine,
simazine, cyanazine) pesticide in the sample.
    In the future, screening methods may be considered for approval
as compliance monitoring methods provided: (1) the method meets all
the requirements described in the regulations at 40 CFR 136.5 and
141.27(c), (2) all positive sample results obtained with the method
are confirmed and

[[Page 15034]]

reported using an approved definitive method, and (3) the
probability of the method producing a false negative result at
concentrations of regulatory interest is no more than one percent
(1%). For part 141 approval, these criteria may be amended when the
Agency implements the requirements for screening methods that are in
the August 2, 1996 amendments to the SDWA.

2.0  Assessing Method Equivalency

    This section provides requirements for assessing the equivalency
of a method that has been modified according to the requirements
specified at 40 CFR 136.4, 136.5(d), 141.27 (b) and (e). Analysts
and regulatory authorities may use these equivalency requirements to
verify and document that equivalent or better method performance
relative to the reference method has been achieved and documented by
the laboratory using the method modification. This section also
specifies requirements for documenting the performance of new
methods and method modifications.
    Good communication among analytical laboratories, regulated
entities, and regulatory authorities is essential for the method
modification assessment process. Although many compliance monitoring
analyses are performed by contract laboratories on behalf of the
regulated entity, the responsibility for maintaining validation
documentation for new and modified methods rests with the regulated
entity. Regulated entities, therefore, must inform their contract
laboratories about the requirements for detailed documentation of
method modifications.

2.1  Requirements for Documenting Validation of New and Modified
Methods

    Although validation requirements vary depending on the intended
use of the new or modified method, the documentation requirements
are the same. A validation study report must be prepared for every
study conducted to validate new or modified methods. The primary
basis for documenting method validations studies are the Checklist
for Initial Demonstration of Method Performance, the Checklist for
Continuing Demonstration of Method Performance, and the
Certification Statement (collectively called the ``Checklists'').
The Checklists must be used by auditors, drinking water laboratory
certification officers, and other reviewers to evaluate new methods
and method modifications against reference methods promulgated at 40
CFR parts 136 and 141.
    The Checklists and instructions for their completion are
provided at Appendix E in this part. Regulated entities must make
the Checklists available to the contract laboratories to document
method modifications. In turn, contract laboratories are responsible
for returning validation study reports including completed
Checklists to the regulated entities.
    The data reviewer should verify that all validation and
documentation requirements appropriate to the intended tier of the
new or modified have been met as specified at 40 CFR 136.4,
136.5(d), 141.27 (b) and (e). For Tier 1 method modifications, the
completed Checklists are adequate to document method equivalency.
For all other validation tiers, the data reviewer must ensure that
the validation study report is complete and includes all supporting
raw data. The following sections must be included in the report:
    2.1.1  A background section that describes the method and the
responsible organization.
    2.1.2  A section that describes the study design and objectives.
    2.1.3  A section that describes the study methodology and
implementation
    2.1.4  A section that describes the procedures that were used to
report and validate data.
    2.1.5  A results section. (Note: Since different instruments
provide different data, the specific form of the supporting
analytical data will differ according to the method. For example,
gas chromatography/mass spectrometry procedures produce
chromatograms, while colorimetric determinations do not.)
    2.1.6  A section for a discussion of the study results.
    2.1.7  A section that describes conclusions from the study.
    2.1.8  An appendix that contains the Checklists.
    2.2  Data Review Guidance for EPA Water Methods
    This section provides guidance for reviewing data submitted to
EPA and state authorities under CWA and SDWA. The guidance provides
a tool for authorities who want to perform detailed inspection of
data analyzed by methods under 40 CFR parts 136 and 141. The
material presented in this section is technically detailed and is
intended for data reviewers familiar with analytical methods.

2.2.1  Standardized Quality Assurance/Quality Control

    Standardized QA/QC is specified for each reference method and
contains the following elements:
    2.2.1.1  Calibration linearity.
    2.2.1.2  Calibration verification.
    2.2.1.3  Absolute and relative retention time precision (for
chromatographic analyses).
    2.2.1.4  Initial precision and recovery or ``start-up'' tests.
    2.2.1.5  Ongoing precision and recovery.
    2.2.1.6  Analysis of blanks.
    2.2.1.7  Surrogate or labeled compound recovery.
    2.2.1.8  Matrix spike and matrix spike duplicate precision and
recovery (for non-isotope dilution analyses).
    2.2.1.9  Demonstration of method detection limits.
    2.2.1.10  Analysis of reference sample.When reviewing method
validation data, the permit writer, PWS, or other individual or
organization has the authority and responsibility to ensure that the
test data submitted contain the elements listed above; otherwise,
the data can be considered noncompliant.

2.2.2  Details of Data Review

    The details of the data review process depend to a great extent
upon the specific analytical method. Even for data from the same
method, there may be many approaches to data review. However, given
the standardized QC requirements of the streamlined methods approval
program, a number of basic concepts apply. The following sections
provide the details for reviewing data submitted and a rationale for
the QC tests. Results from all QC tests must be within the QC
acceptance criteria specified in, or associated with, the reference
method to validate that results produced by a method modification
are equivalent or superior to results produced by the reference
method.

2.2.2.1  Calibration linearity

    The relationship between the response of an analytical
instrument to the concentration or amount of an analyte introduced
into the instrument typically is represented by an averaged response
or calibration factor, a calibration line, or a calibration curve.
An analytical instrument can be said to be calibrated in any
instance in which an instrumental response can be related to a
single concentration of an analyte. The response factor or
calibration factor is the ratio of the response of the instrument to
the concentration (or amount) of analyte introduced into the
instrument.
    Nearly all analytical methods focus on the range over which the
response is a linear function of the concentration of the analyte.
This range usually extends from the minimum level of quantitation
(ML) on the low end to the point at which the calibration becomes
non-linear on the high end. For regulatory compliance, it is
important that the concentration of regulatory interest (e.g.,
permit limit; MCL) fall within this range. Calibration can also be
modeled by quadratic or higher order mathematical functions. The
advantage of a calibration line that passes through the origin is
that an averaged response factor or calibration factor can be used
to represent the slope of this line. Use of a single factor
simplifies calculations and the interpretation of the data. Also, it
is easier to discern when an inaccurate calibration standard has
been prepared if the calibration function is a straight line.
    Many analytical methods, particularly recent methods, specify
some criterion for determining the linearity of the calibration.
When this criterion is met, the calibration function is sufficiently
close to a straight line that passes through the origin to permit
the laboratory to use an averaged response factor or calibration
factor. Linearity is determined by calculating the relative standard
deviation (RSD) of the response factor or calibration factor for
each analyte and comparing this RSD to the limit specified in the
method. If the RSD does not exceed the specification, linearity
through the origin is assumed. If the specification is not met, a
calibration curve must be used.
    For whatever calibration range is used, a reference method
should contain a specification for the RSD of the response or
calibration factor to establish the breakpoint between linear
calibration through the origin and a line not through the origin or
a calibration curve. For new methods, the method developer must
provide the RSD results by which one can judge linearity, even in
instances where the laboratory is using a calibration curve. In
instances where

[[Page 15035]]

the laboratory employs a curve rather than an average response or
calibration factor, the data reviewer should review each calibration
point to ensure that the response increases as the concentration
increases. If it does not, the instrument is not operating properly,
or the calibration curve is out of the range of that instrument, and
data are not considered valid.

2.2.2.2  Calibration Verification

    Calibration verification involves the analysis of a single
standard at the beginning of each analytical shift or after the
analysis of a fixed number of samples (e.g., 10). The concentration
of each analyte in this standard is normally at the same level as in
one of the calibration standards, typically at 1--5 times the ML.
The concentration of each analyte in this standard is calculated
using the calibration data. The calculated concentration is compared
to the concentration of the standard. Calibration is verified when
the concentration is within the calibration verification limits
specified in the method. If the results are within the
specifications, the laboratory is allowed to proceed with analysis
without recalibrating and allowed to use the calibration data to
quantify the sample concentration or amount of each analyte in
samples, blanks, and QC tests.
    If calibration cannot be verified, the laboratory may either
recalibrate the instrument or prepare a fresh calibration standard
and make a second attempt to verify calibration. If calibration
cannot be verified with a fresh calibration standard, the instrument
must be recalibrated. If calibration is not verified, subsequent
data are considered to be invalid until the instrument is
recalibrated.

2.2.2.3  Absolute and Relative Retention Time Precision

    Retention time specification aid in the identification of
analytes in chromatographic analyses. In some methods, a minimum
retention time is specified to ensure adequate separation of
analytes in complex mixtures. If retention time QC criteria cannot
be verified, chromatographic identification of analytes is suspect
and reanalysis is necessary.

2.2.2.4  Initial Precision and Recovery

    The laboratory must demonstrate that it can meet the IPR QC
acceptance criteria in the method. This test is required prior to
the use of the method by a laboratory. It is sometimes termed the
``start-up test.'' Difficulty in passing the start-up test
frequently leads to marginal performance by the laboratory in the
routine operation of the method. Performing the start-up test
``after the fact'' or after samples have been analyzed is not
acceptable.
    The start-up test consists of spiking the analytes of interest
into a set of four or more aliquots of a reference matrix and
analyzing these four aliquots. The reference matrix simulates the
medium being tested. A separate IPR test must be performed for each
medium. The mean concentration and the standard deviation of the
concentration are calculated for each analyte and compared to QC
acceptance criteria in the method. If the mean and standard
deviation are within the limits specified, the analysis system is in
control and the laboratory can use the system for analysis of
blanks, field samples, and other QC tests samples. For some methods
(e.g., EPA Methods 625 and 1625), a repeat test is allowed because
of the large number of analytes being tested simultaneously.
    If there are no start-up test data, or if these data fail to
meet the QC acceptance criteria in the method, all data produced by
that laboratory using that method are not considered valid. It is
important to remember that if a change is made to a method, the
start-up test must be repeated with the change as an integral part
of the method. Such changes may involve alternative extraction,
concentration, or cleanup processes; alternative GC columns, GC
conditions, or detectors; or other procedures designed to address a
particular matrix problem. If the start-up test is not repeated when
a procedure is changed, added, or deleted, data produced by the
modified method are considered invalid.

2.2.2.5  Ongoing Precision and Recovery

    An ongoing precision and recovery (OPR) standard (also termed a
``laboratory control sample'' (LCS) or a ``laboratory fortified
blank'' (LFB)) must be analyzed with each sample batch prior to the
analysis of a blank, sample, or matrix spike or duplicate. The
number of samples in the batch is usually 10 or 20, depending on the
method, or the OPR is required at the beginning of an analysis
shift, regardless of the number of samples analyzed during that
shift. The data reviewer must determine if the OPR standard has been
run with each sample batch or at the beginning of the shift and if
all criteria have been met. If the standard was not run with a given
set of samples, or if the criteria are not met, the results for that
set of samples are considered invalid.

2.2.2.6  Analysis of blanks

    Blanks must be analyzed either on a periodic basis or with each
sample batch, depending on the method. Blanks may contain
contamination at levels no higher than specified in the method.
Samples associated with a contaminated blank must be reanalyzed.

2.2.2.7  Surrogate or Labeled Compound Recovery

    Surrogate or labeled compounds are used to assess the
performance of the method on each sample. Recoveries of these
compounds from each sample must be within QC acceptance criteria to
demonstrate acceptable method performance on the sample. If the
recovery is not within the criteria, the sample is normally diluted
and the dilute sample analyzed to demonstrate that a matrix effect
precluded reliable analysis of the undiluted sample.

2.2.2.8  Matrix Spike and Matrix Spike Duplicate

    Non-isotope dilution methods require a spike of the analytes of
interest into a separate aliquot of the sample for analysis with the
sample. The purpose of the matrix spike (sometimes termed a
``laboratory fortified sample matrix'' (LFM)) is to determine if the
method is applicable to the sample in question. While many of the
approved methods were tested using effluents from a wide variety of
industries, samples from some sources may not yield acceptable
results. It is, therefore, important to evaluate method performance
in the sample matrix of interest. If the recovery for the MS/MSD is
not within the QC acceptance criteria, a matrix interference may be
the cause. The sample is usually diluted and the diluted sample
spiked and analyzed. If the QC acceptance criteria are met with the
diluted MS/MSD, a matrix problem exists. Cleanup and other
processing of the sample are then required to overcome the matrix
interference if analysis of the undiluted sample is required to
establish compliance.

2.2.2.9  Demonstration of Method Detection Limits

    A laboratory that wishes to use a new or modified wastewater
method must demonstrate that the method detection limit (MDL)
specified in the reference method can be achieved. Alternatively, if
the regulatory wastewater compliance limit is above the MDL,
laboratories must demonstrate that the minimum level (ML) determined
with the new or modified method is at or below \1/3\ the compliance
limit. A laboratory that wishes to use a new or modified drinking
water method must demonstrate that the MDL determined with that
method meets the detection limits specified at 40 CFR parts 141.23,
141.24 and 141.89 and/or as specified at 40 CFR 141.27(d). For both
drinking water and wastewater determinations, demonstration of a
valid detection limit requires use of an MDL study in accordance
with the procedure at 40 CFR part 136 Appendix B. If the MDL
determined with the new or modified method is not acceptable, the
method may not be used because the laboratory has not demonstrated
an ability to detect the analyte at the level required.

    Note: Required detection limits specified in regulations and/or
in the reference method(s) are usually analyte-specific; for the
same analyte, the requirement may differ between the wastewater and
the drinking water reference method.

2.2.2.10  Reference Sample Analysis

    Provided such acceptance limits are specified by EPA or other
regulatory authorities, a laboratory must be able to demonstrate the
ability to quantitate the analyte in a reference material to within
the acceptance range specified for the reference material.
Currently, EPA specifies at 40 CFR 141.23, 141.24 and 141.89
acceptance limits for analysis of performance evaluation (PE)
samples that are provided by EPA under the drinking water studies
(WS) PE-sample program.

3.0  Method Approval Process

    Use of the procedures specified in this section will expedite
the approval of drinking and wastewater methods by ensuring that
methods submitted to EPA for approval contain the appropriate
elements, have been validated, and contain all supporting
documentation. This section details procedures for preparing and
submitting method documentation, and describes the rulemaking
process required to

[[Page 15036]]

approve a new method or method modification. All new wastewater and
drinking water methods are subject to EPA review. New methods
recommended for approval will be subject to one of two actions: an
approval letter or an Agency rulemaking. Tier 1 new methods will
receive a letter of approval from EPA/EAD. Tier 2 and 3 new methods
will be approved in a formal rulemaking. Rulemaking involves
publishing in the Federal Register a proposed rule containing the
method(s) for public comment, responding to public comment, and
approving the method(s) in a final rule. The approved method(s) will
be cited in the applicable parts of the CFR. The text of the
approved method(s) will be incorporated by reference rather than
published in the CFR. The method submitter will be responsible for
developing, writing, and validating the method; providing
information in a format suitable for a proposed rule; providing the
necessary supporting documentation; and assisting EPA in responding
to public comments to support approval. EPA will review the method
and supporting documents, draft the regulatory language, and submit
the proposed rule to the Office of the Federal Register (OFR) for
publication in the Federal Register. New methods must undergo the
processes detailed above; no other types of action will be
substituted.
    Method modifications can be used directly after the method
validation study confirms method equivalency. EPA, only upon
request, will review Tier 2 and Tier 3 method modifications. The
option to request EPA review of a modified method is provided to
allow interested parties to substantiate EPA approval of a method
modification. Any party associated with method modification and/or
development can request review, including: permittees, publicly
owned treatment works (POTWs), public water systems (PWSs),
commercial laboratories, vendors, or States. Upon determination that
a method modification is appropriate, EPA either will issue a letter
of approval or conduct a rulemaking, whichever action is requested
by the method submitter. The text of the approved method(s) will be
incorporated by reference rather than published in the CFR. The
method submitter will be responsible for developing, writing, and
validating the method; providing information in a format suitable
for a proposed rule; providing the necessary supporting
documentation; and assisting EPA in responding to public comments to
support approval. EPA's role will be to review the method and
documentation; to write the rule language; and to submit the rule to
the OFR, if appropriate.

3.1  Pre-Submission Procedures

    EPA must review all new methods, and will review Tier 2 and Tier
3 method modifications upon request. Prior to EPA review, a party
developing a new or modified method will proceed through up to four
steps: (1) method development, (2) method validation, (3)
information in a format suitable for proposal in the Federal
Register (if appropriate), and (4) submission to EPA.

3.1.1  Method Development

    Any person can develop a new method or method modification if
they identify a new or improved procedure or technique for analyzing
an analyte of interest. A new method must be a unique combination of
analyte and determinative technique, as discussed in Section 1.
Otherwise, it would qualify as a modification of an existing method.
The method development process will typically include drafting,
checking, and modifying testing procedures. Once the person has
confidence in the new or modified testing procedures, the procedures
should be finalized into a standardized format. The method
description should identify the anticipated application of the new
procedures: single laboratory; multi-laboratory, single matrix type;
or multi-laboratory, multiple matrix types.
    The requirement to provide the method in standard format is
needed to preclude confusion. Specific details on the standard
format for the new or modified method can be found at Appendix F of
this part. Appendix F specifies the analytical methods format
developed by EPA's Environmental Monitoring Management Council
(EMMC). The EMMC format is directed at standardizing all Agency
analytical methods.
    For new methods submitted for approval at 40 CFR part 136 or
part 141, a format from another organization may be used provided
that it is standardized and contains the same elements specified in
the Method Guidelines and Format. For example, the method format
documents from Standard Methods, ASTM, AOAC-International, or USGS
are acceptable because these formats are documented and routinely
followed by these organizations. However, method submitters other
than these organizations must use the EPA format specified at
Appendix F of this part. Reserving method formats for those specific
organizations avoids misleading the analytical community concerning
the authorship of the method. EPA will review and approve
standardized formats from governmental authorities and industrial
associations upon request, but will not approve miscellaneous
formats written by instrument manufacturers, individual
laboratories, and others because of the potential proliferation of
different method formats. The format provided in Appendix F of this
part meets the needs of a format for new methods.

3.1.2  Method Validation

    Each new method or method modification must be tested to assess
its performance. The process of establishing or substantiating
method performance is called validation. To approve a new method or
method modification, EPA must be provided with a report describing
and including results of the validation study. When undertaking
method validation, the method submitter is responsible for
performing the validation study at the appropriate tier as specified
at Secs. 136.4, 136.5 and 141.27. The study will be detailed in a
method validation report submitted to EPA that includes the required
Checklists and Certification Statement as specified at Appendix E of
this part.
    For new methods, QC acceptance criteria must be included in the
method and the details of development of these criteria must be
included in the validation report. QC acceptance criteria are used
to ensure that a method produces results that are reliable,
defensible, and suitable for regulatory decisions. QC acceptance
criteria must be developed from data gathered in a method validation
study. When an analyte is being added to an approved method,
however, QC acceptance criteria may be (1) developed from validation
data, (2) transferred from another analyte already included in the
approved method, (3) transferred from another analyte in another
approved method, or (4) transferred from another approved method for
the same analyte. For a transfer from another analyte to be
appropriate, the chemical characteristics of the analyte from which
the criteria are transferred should simulate, as closely as
possible, the chemical characteristics of the newly regulated
analyte. For example, if 2,4-dimethyl-3-chlorophenol is added to
Method 625, and data from a method validation study are not
available from which QC acceptance criteria can be derived, QC
acceptance criteria can be transferred from 2,4-dimethylphenol or 4-
chloro-3-methylphenol in Method 625. For newly regulated analytes
added to an existing method, it is highly likely that EPA would
require that the QC acceptance criteria be developed from validation
data rather than transferring criteria from another analyte to
ensure proper validation.

3.1.3  Draft Federal Register Preamble

    When Tier 2 and Tier 3 methods are to undergo the rulemaking
process (e.g., for all new methods and modified methods requests),
the submitter must provide information in a format suitable for
proposal of the method at 40 CFR parts 136 or 141. This information
should describe the basis and purpose for the proposed rule and
should be written to communicate the import of the rule to the
general public. The OFR requires a specific format for the preamble.
Examples of appropriate and pertinent preambles include 49 FR 43234,
October 26, 1984; 56 FR 5090, February 7, 1991; 60 FR 53988, October
18, 1995; and 61 FR 1730, January 23, 1996.

3.1.4  Submission to EPA

    When all the pre-submission steps are completed, the method
submitter should generate a single packet for submission to EPA.
This packet will include the method in a standard format, the method
validation report, the draft preamble (if rulemaking will occur),
and any necessary supporting documents. If this streamlining
proposal is promulgated, the submission packet will be submitted to
the Director of the Analytical Methods Staff in EPA's Office of
Water.

3.2  EPA Review

    EPA must review all new methods, and will review Tier 2 and Tier
3 method modifications if requested. When a method package is
submitted for review, EPA will first check the documentation for
completeness. The documentation must include the final method in
standard format, the validation report, and information that would
facilitate EPA's drafting of a proposed rule (if rulemaking will
occur). If all of the

[[Page 15037]]

documentation is in order, EPA will begin an internal review of the
method for scientific merit, consistency, and appropriateness. The
internal review may involve multiple programs and workgroups. Should
any problems or questions arise, EPA will communicate with the
submitter to resolve the outstanding issues. Depending on the
circumstances, EPA may return the submission to the submitter for
revision.
    If internal review recommends acceptance, EPA will issue a
letter of acceptance for a Tier 1 new method. For Tier 2 and Tier 3
new methods, EPA will begin the rulemaking process. For Tier 2 and
Tier 3 method modifications, the method submitter has the option of
receiving a letter of approval or proceeding with the rulemaking
process.

             Table 1-1.--EPA Review and Approval of Methods
------------------------------------------------------------------------
                                   New method          Modified method
------------------------------------------------------------------------
Tier 1: Single-lab..........   EPA review   No EPA review.
                               required.
                               EPA issues
                               a letter of
                               approval
Tier 2: Multi-lab, single      EPA review    If
 matrix type.                  required.             requested, EPA
                               Approved      reviews and issues
                               through rulemaking    letter of approval,
                                                     or conducts
                                                     rulemaking.
Tier 3: Multi-lab, multiple    EPA review    If
 matrix type.                  required.             requested, EPA
                               Approved      reviews and issues
                               through rulemaking    letter of approval,
                                                     or conducts
                                                     rulemaking.
------------------------------------------------------------------------

3.3  Limited Use Methods

    Currently, EPA reviews single-laboratory, limited-use methods
only for special applications. Examples of special circumstances
could include procedures to remove sulfate interferences in drinking
water matrices and, as described below, technologies that can
eliminate total cyanide false positives in some wastewater
measurements.
    Use of limited-use methods as Tier 1 methods for both wastewater
and drinking water methods is allowed. The purpose of this allowance
is to provide the means by which (1) a new technology can be
introduced and (2) specific matrix interference problems can be
overcome. Furthermore, additional single laboratories can use the
technology until a sufficient number of devices are available for
interlaboratory validation.
    Tier 1 new methods must be submitted to EPA for review. Upon
recommendation for approval, a letter of approval will be issued.
Tier 1 modified methods can be used directly upon validation. EPA
will not review Tier 1 method modifications.

3.4  Rulemaking Process

    The customary rulemaking process consists of four phases:
proposal of the rule, public comment, response to comments, and
publication of the final rule. The proposed rule requests public
comment and allows a specified comment period, for example, 30 to 90
days depending on the magnitude of the proposed change. At the end
of the comment period, EPA will forward any significant comments to
the method submitter. The submitter would then provide technical
assistance to EPA in drafting responses to comments. All comments
that have scientific or legal merit, or raise substantive issues
with the proposed rule, must be answered to complete the rule-making
process.
    EPA will review the comment responses and complete a response-
to-comments document that must be included in the final rule. EPA
will prepare and submit the final rule to the OFR for publication.
The final rule will state the date that the rule becomes effective;
as of this date, the method is approved.

3.5  Proprietary Components

    Proprietary components can be classified into three categories:
proprietary reagents, proprietary instruments, and proprietary
methods. Proprietary reagents and instruments are allowed in the
approval of analytical methods for compliance purposes to the extent
that such inclusion still provides an adequate opportunity for
public review and comment under the Administrative Procedure Act.
Use of proprietary methods for determining compliance with
regulatory requirements where the entire method is claimed as
``confidential business information'' (CBI) is not allowed. However,
if the proprietary method is patented it could be considered for
approval because the public would have the opportunity to comment on
the patented method.
    Proprietary reagents and instruments are allowed in approved
methods. The details of the proprietary elements must be disclosed
to EPA, but will be withheld from the public if the person
requesting protection for the CBI demonstrates that the information
is entitled to confidential treatment under the applicable
regulations. Examples of these proprietary components are
immunoassay reagents and antibodies, and liquid phases in GC
columns, e.g., DB-1, SPB-octyl, Dexsil, etc. A
new or modified method submitted for EPA approval must include
language stating that the proprietary reagent or instrument can be
replaced by an equivalent. Changes made to the method after EPA
approval would require the manufacturer to demonstrate through
supporting documentation that the new proprietary equipment,
substance, or reagent would produce results equal or superior to
results produced with the material originally tested and on which
the method approval is based. For proprietary reagents, a method
must contain accurate, specific instructions for the safe handling
of each proprietary reagent listed in the method, and for safe
disposal of each spent proprietary reagent and/or reagent product.
When a material safety data sheet (MSDS) accompanies the proprietary
material, the MSDS will serve as these instructions, and the
submission of an MSDS with the method shall be evidence that the
requirements for instructions for safe handling and disposal of the
reagent have been met.

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, and 300j-9.

    2. Section 141.2 is proposed to be amended by adding the following
definitions in alphabetical order to read as follows:

Sec. 141.2  Definitions.

    As used in this part, the term:
    Accuracy means the degree of agreement between an observed value
and an accepted reference value. Accuracy includes random error
(precision) and systematic error (bias) that are caused by sampling and
analysis.
* * * * *
    Administrator means the Administrator of the U.S. Environmental
Protection Agency (EPA).
    Analyte or Analyte of concern means a substance or property that is
to be measured by an analysis.

    Approved method means a testing procedure (analytical method)
promulgated at this part or at 40 CFR part 142 or 143.

    Assistant Administrator (AA) means the EPA Assistant Administrator
for Water.
* * * * *
    Calibration (CAL) means the process of establishing the
relationship between the concentration or amount of material introduced
into an instrument or measurement process and the output signal.
    Calibration linearity means the degree to which calibration points
lie along a straight line.
    Calibration verification means the means of establishing that
instrument

[[Page 15038]]

performance remains within pre-established limits.
* * * * *
    Determinative technique means the process (physical or chemical or
both) to measure the identity and concentration of an analyte. In test
methods, the determinative technique follows the front-end techniques.
* * * * *
    Front-end technique means any technique in the analytical process
that precedes the determinative technique, including all procedures,
equipment, solvents, etc. that are used in the laboratory in the
preparation and cleanup of a sample but this excludes conditions and/or
procedures for the collection, preservation, shipment and storage of
the sample.
* * * * *
    Initial precision and recovery test (IPR) means analysis of a
minimum of four spiked reagent water samples under the same conditions
as will be used for analysis of environmental samples. The IPR is used
to demonstrate that a laboratory is able to produce reliable results
with the method prior to analysis of environmental samples.
    Interference means a positive or negative effect on a measurement
caused by a substance other than the analyte being investigated.
* * * * *
    Matrix means the component or substrate that contains the target
analyte.
    Matrix spike (MS) means a sample prepared by adding a known mass of
target analyte to a specified amount of a sample matrix for which an
independent estimate of target analyte concentration is available.
    Matrix spike duplicate (MSD) means a duplicate of the matrix spike.
The MS/MSD are used in combination to test the precision of an
analysis.
    Matrix type is any potable water sample provided by a PWS.
* * * * *
    Medium means the physical phase of a sample matrix. Air, water,
soil, sediment, rock, and sludge are sample media.
* * * * *
    Method means an orderly and systematic arrangement of procedures
and techniques for performing an analysis.
    Method blank (or blank) means a sample absent the analytes of
interest and interferences that is processed through all steps of a
method simultaneously with and under the same conditions as samples
that may contain an analyte of interest.
    Method detection limit (MDL) means the minimum concentration of a
substance that can be measured and reported with 99% confidence that
the analyte concentration is greater than zero as determined by the
procedure set forth in appendix B of this part.
    Method Guidelines and Format means the procedures set forth in
appendix F of part 136.
    Method modification means a change to a reference method. The
change may be to a front-end technique or to the determinative
technique.
    Method validation means a process by which a laboratory or vendor
establishes the performance of a new method or substantiates the
performance of a reference method modification.
    Minimum level (ML) means the lowest level at which an entire
analytical system gives a recognizable signal and acceptable
calibration point for an analyte. It is equivalent to the concentration
of the lowest calibration standard, assuming that all method-specified
sample weights, volumes, and clean-up procedures have been employed.
* * * * *
    New method means a combination of analyte of concern and
determinative technique that is different from those in the approved
methods.
* * * * *
    Ongoing precision and recovery sample (OPR) means a spiked
reference matrix sample that is processed through all steps of a method
simultaneously with and under the same conditions as samples that may
contain an analyte of interest. Also called a laboratory control sample
(LCS), the OPR/LCS is used to demonstrate that a laboratory is able to
produce reliable results continuously.
* * * * *
    Organic Methods means the document titled: Methods for the
Determination of Organic Compounds in Drinking Water--Supplement III
(available from the National Technical Information Service (NTIS), U.S.
Department of Commerce, Springfield, Virginia, 22161, 703/487-4600, at
NTIS publication PB97-125298).
    Other approved method means a promulgated method that is not
designated as a reference method.
    Percent recovery means the recovery multiplied by one hundred.
 * * * * *
    Precision means the degree to which a set of observations or
measurements of the same property, usually obtained under similar
conditions, conform to themselves. Precision is usually expressed as
standard deviation, variance, or range, in either absolute or relative
terms.
    Preparation means processing performed on a sample prior to
analysis, including extraction, concentration, and cleanup.
    Procedure means a set of systematic instructions for performing an
activity.
    Promulgated method means a method that has been published or
incorporated by reference into 40 CFR parts 141, 142, or 143.
 * * * * *
    Quality assurance (QA) means an integrated system of activities
involving planning, quality control, quality assessment, reporting, and
quality improvement to ensure that a product or service meets defined
standards of quality with a stated level of confidence.
    Quality control (QC) means the overall system of technical
activities whose purpose is to measure and control the quality of a
product or service so that it meets the needs of a user. The aim is to
provide quality that is satisfactory, adequate, dependable, and
economical.
    QC acceptance criteria means performance specifications developed
from validation data and used to control the limits within which an
analytical method is operated.
    Range means the amounts or concentrations over which an instrument
or analytical system is calibrated.
    Recovery means the total amount of analyte found divided by the
amount of analyte added as a spike.
    Reference method means an approved method that is designated as a
standard to which a modified method can be compared. A reference method
will include standardized QC and QC acceptance criteria as well as
sample preparation, cleanup, and other procedures.
    Regional Administrator means an EPA Regional Administrator.
 * * * * *
    Sample means a portion of a larger whole or a single item of a
group; a finite part or subset of a statistical population; the medium
subjected to analysis. A sample serves to provide data or information
concerning the properties of the whole or population.
    Sample matrix effect validation means to verify that the
performance of a modified or new analytical method on samples obtained
from different PWSs does not differ from the results validated in
reagent water samples.
 * * * * *
    Screening method means a method that employs a qualitative
determinative technique for an analyte of interest that

[[Page 15039]]

is different from the determinative techniques used in all approved
methods for that analyte. The screening method must produce a false
negative probability less than 1%.
 * * * * *
    Selectivity means the capability of a method or instrument to
respond to an analyte in the presence of interferences.
    Sensitivity means the capability of a method or instrument to
differentiate between different amounts or concentrations of an
analyte.
 * * * * *
    Spike means the process of adding a known amount of an analyte to a
sample to determine the recovery.
    Spike amount means a known mass of analyte added to a sample and
used to determine the recovery of a method.
    Standard deviation means the measure of the dispersion of observed
values expressed as the positive square root of the sum of the squares
of the difference between the individual values of a set and the
arithmetic mean of the set, divided by one less than the number of
values in the set.
 * * * * *
    Standardized quality control (standardized QC) means a uniform set
of performance testing procedures that ensure reliable results.
Depending on the method, standardized QC procedures include, but are
not limited to, the following: calibration, calibration linearity,
calibration verification, absolute retention time, absolute and
relative retention time precision, initial precision and recovery,
ongoing precision and recovery (laboratory control sample), surrogate
or labeled compound recovery, analysis of blanks, matrix spike and
matrix spike duplicate recovery and precision, demonstration of method
detection limit(s), and analysis of a reference sample.
 * * * * *
    Surrogate means a substance with properties that mimic the behavior
of an analyte, that is unlikely to be found in an environmental sample,
and that is added to the sample for quality control purposes.
 * * * * *
    Tier 1 means the application of a new or modified method in a
single laboratory to one or more PWSs .
    Tier 2 means the application of a new or modified method by all
laboratories to all PWSs (nationwide use).
* * * * *
    3. Section 141.23, paragraph (k)(1), is proposed to be amended by
revising the table to read as follows:

Sec. 141.23  Inorganic chemical sampling and analytical requirements.

* * * * *
    (k) * * *
    (l) * * *

                                             Table 141.23(k)(1)--List of Approved Inorganic Test Procedures
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                  Other approved methods
          Contaminant                 Methodology      Reference ---------------------------------------------------------------------------------------
                                                         method      EPA            ASTM 3,13                  SM4,13                     Other
--------------------------------------------------------------------------------------------------------------------------------------------------------
Antimony                         ICP-Mass              \2\ 200.8            ........................  ........................  ........................
                                  Spectrometry
                                 Hydride-Atomic                             D-3697-92                 ........................  ........................
                                  Absorption
                                 Atomic Absorption;    \2\ 200.9            ........................  ........................  ........................
                                  Platform
                                 Atomic Absorption;                         ........................  3113B                     ........................
                                  Furnace
Arsenic                          Inductively Coupled   \2\ 200.7            ........................  3120B                     ........................
                                  Plasma
                                 ICP-Mass              \2\ 200.8            ........................  ........................  ........................
                                  Spectrometry
                                 Atomic Absorption;    \2\ 200.9            ........................  ........................  ........................
                                  Platform
                                 Atomic Absorption;                         D-2972-93C                3113B                     ........................
                                  Furnace
                                 Hydride-Atomic                             D-2972-93B                3114B                     ........................
                                  Absorption
Asbestos                         Transmission          \10\ 100.  \9\ 100.  ........................  ........................  ........................
                                  Electron Microscopy          2         1
Barium                           Inductively Coupled   \2\ 200.7            ........................  3120B                     ........................
                                  Plasma
                                 ICP-Mass              \2\ 200.8            ........................  ........................  ........................
                                  Spectrometry
                                 Atomic Absorption;                         ........................  3111D                     ........................
                                  Direct
                                 Atomic Absorption;                         ........................  3113B                     ........................
                                  Furnace
Beryllium                        Inductively Coupled   \2\ 200.7            ........................  3120B                     ........................
                                  Plasma
                                 ICP-Mass              \2\ 200.8            ........................  ........................  ........................
                                  Spectrometry
                                 Atomic Absorption;    \2\ 200.9            ........................  ........................  ........................
                                  Platform
                                 Atomic Absorption;                         D-3645-93B                3113B                     ........................
                                  Furnace
Cadmium                          Inductively Coupled   \2\ 200.7            ........................  ........................  ........................
                                  Plasma
                                 ICP-Mass              \2\ 200.8            ........................  ........................  ........................
                                  Spectrometry
                                 Atomic Absorption;    \2\ 200.9            ........................  ........................  ........................
                                  Platform
                                 Atomic Absorption;                         ........................  3113B                     ........................
                                  Furnace
Chromium                         Inductively Coupled   \2\ 200.7            ........................  3120B                     ........................
                                  Plasma
                                 ICP-Mass              \2\ 200.8            ........................  ........................  ........................
                                  Spectrometry
                                 Atomic Absorption;    \2\ 200.9            ........................  ........................  ........................
                                  Platform
                                 Atomic Absorption;                         ........................  3113B                     ........................
                                  Furnace
Cyanide                          Manual Distillation                        ........................  4500-CN-C                 ........................
                                  followed by
                                   Spectrophotometric                       D-2036-91B                4500-CN-G                 ........................
                                  , Amenable
                                   Spectrophotometric                       D2036-91A                 4500-CN-E                 \5\ I-3300-85
                                  , Manual
                                     Semi-automated    \6\ 335.4            ........................  ........................  ........................
                                 Selective Electrode                        ........................  4500-CN-F                 ........................
Fluoride                         Ion Chromatography    \6\ 300.0            D4327-91                  4110B                     ........................
                                 Manual Distill.;                           ........................  4500-F-B,D                ........................
                                  Color. SPADNS
                                 Manual Electrode                           D1179-93B                 4500-F-C                  ........................
                                 Automated Electrode                        ........................  4500-F-E                  \11\ 380-75WE
                                 Automated Alizarin                         ........................  ........................  \11\ 129-71W
Mercury                          Manual, Cold Vapor    \2\ 245.1            D3223-91                  3112B                     ........................
                                 Automated, Cold       \1\ 245.2            ........................  ........................  ........................
                                  Vapor
                                 ICP-Mass              \2\ 200.8            ........................  ........................  ........................
                                  Spectrometry
Nickel                           Inductively Coupled   \2\ 200.7            ........................  3120B                     ........................
                                  Plasma
                                 ICP-Mass              \2\ 200.8            ........................  ........................  ........................
                                  Spectrometry
                                 Atomic Absorption;    \2\ 200.9            ........................  ........................  ........................
                                  Platform
                                 Atomic Absorption;                         ........................  3111B                     ........................
                                  Direct

[[Page 15040]]


                                 Atomic Absorption;                         ........................  3113B                     ........................
                                  Furnace
Nitrate                          Ion Chromatography    \6\ 300.0            D4327-91                  4110B                     \8\ B-1011
                                 Automated Cadmium     \6\ 353.2            D3867-90A                 4500-NO3-F                ........................
                                  Reduction
                                 Ion Selective                              ........................  4500-NO3-D                \7\ 601
                                  Electrode
                                 Manual Cadmium                             D3867-90B                 4500-NO3-E                ........................
                                  Reduction
Nitrite                          Ion Chromatography    \6\ 300.0            D4327-91                  4110B                     \8\ B-1011
                                 Automated Cadmium     \6\ 353.2            D3867-90A                 4500-NO3-F                ........................
                                  Reduction
                                 Manual Cadmium                             D3867-90B                 4500-NO3-E                ........................
                                  Reduction
                                 Spectrophotometric                         ........................  4500-NO2-B                ........................
Selenium                         Hydride-Atomic                             D3859-93A                 3114B                     ........................
                                  Absorption
                                 ICP-Mass              \2\ 200.8            ........................  ........................  ........................
                                  Spectrometry
                                 Atomic Absorption;    \2\ 200.9            ........................  ........................  ........................
                                  Platform
                                 Atomic Absorption;                         3859-93B                  3113B                     ........................
                                  Furnace
Thallium                         ICP-Mass              \2\ 200.8            ........................  ........................  ........................
                                  Spectrometry
                                 Atomic Absorption;    \2\ 200.9            ........................  ........................  ........................
                                  Platform
Lead                             Atomic Absorption;                         D3559-90D                 3113B                     ........................
                                  Furnace
                                 ICP-Mass              \2\ 200.8            ........................  ........................  ........................
                                  Spectrometry
                                 Atomic Absorption;    \2\ 200.9            ........................  ........................  ........................
                                  Platform
Copper                           Atomic Absorption;                         D1688-90C                 3113B                     ........................
                                  Furnace
                                 Atomic Absorption;                         D1688-90A                 3111B                     ........................
                                  Direct Aspiration
                                 ICP                   \2\ 200.7            ........................  3120B                     ........................
                                 ICP-Mass              \2\ 200.8            ........................  ........................  ........................
                                  Spectrometry
                                 Atomic Absorption;    \2\ 200.9            ........................  ........................  ........................
                                  Platform
pH                               Electrometric         \1\ 150.2  \1\ 150.  D1293-84                  4500-H+-B                 ........................
                                                                         1
Conductivity                     Conductance                                D1125-91A                 2510B                     ........................
Calcium                          EDTA Titrimetric                           D511-93A                  3500-Ca-D                 ........................
                                 Atomic Absorption;                         D511-93B                  3111B                     ........................
                                  Direct Aspiration
                                 Inductively Coupled   \2\ 200.7            ........................  3120B
                                  Plasma
Alkalinity                       Titrimetric                                D1067-92B                 2320B                     ........................
                                 Electrometric                              ........................  ........................  \5\ I-1030-85
                                  Titration
Orthophosphate \12\              Colorimetric,         \6\ 365.1            ........................  4500-P-F                  ........................
                                  Automated, Ascorbic
                                  Acid
                                 Colorimetric,                              D515-88A                  4500-P-E                  ........................
                                  Ascorbic Acid,
                                  Single Reagent
                                 Colorimetric,                              ........................  ........................  \5\ I-1601-85
                                  Phosphomolybdate;
                                   Automated-                               ........................  ........................  \5\ I-2601-90
                                  segmented flow;
                                 Automated discrete                         ........................  ........................  \5\ I-2598-85
                                 Ion Chromatography    \6\ 300.0            D4327-91                  4110                      ........................
Silica                           Colorimetric,                              ........................  ........................  \5\ I-1700-85
                                  Molybdate Blue;
                                   Automated-                               ........................  ........................  \5\ I-2700-85
                                  segmented flow
                                 Colorimetric                               D859-88                   ........................  ........................
                                 Molybdosilicate                            ........................  4500-Si-D                 ........................
                                 Heteropoly Blue                            ........................  4500-Si-E                 ........................
                                 Automated Method for                       ........................  4500-Si-F                 ........................
                                  Molybdate-Reactive
                                  Silica
                                 Inductively Coupled   \2\ 200.7            ........................  3120B                     ........................
                                  Plasma
Temperature                      Thermometric                               ........................  2550                      ........................
Sodium                           Inductively Coupled   \2\ 200.7            ........................  ........................  ........................
                                  Plasma
                                 Atomic Absorption;                         ........................  3111B                     ........................
                                  Direct Aspiration
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Methods 150.1, 150.2 and 245.2 are available from U.S. EPA, NERL, Cincinnati, OH 45268. The identical methods were formerly in ``Methods for
  Chemical Analysis of Water and Wastes'', EPA-600/4-79-020, March 1983, which is available at NTIS, PB84-128677.
\2\ ``Methods for the Determination of Metals in Environmental Samples--Supplement 1'', EPA-600/R-94-111, May 1994. Available at NTIS, PB 94-184942.
\3\ The procedures shall be done in accordance with the Annual Book of ASTM Standards, 1994, Vols. 11.01 and 11.02, American Society for Testing and
  Materials. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51.
  Copies may be obtained from the American Society for Testing and Materials, 1916 Race Street, Philadelphia, PA 19103. Copies may be inspected at EPA's
  Drinking Water Docket, 401 M Street, S.W., Washington, DC 20460; or at the Office of the Federal Register, 800 North Capitol Street, N.W., Suite 700,
  Washington, DC.
\4\ The procedures shall be done in accordance with the 18th edition of Standard Methods for the Examination of Water and Wastewater, 1992, American
  Public Health Association. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and
  1 CFR Part 51. Copies may be obtained from the American Public Health Association, 1015 Fifteenth Street, N.W., Washington, DC 20005. Copies may be
  inspected at EPA's Drinking Water Docket, 401 M Street, S.W., Washington, DC 20460; or at the Office of the Federal Register, 800 North Capitol
  Street, N.W., Suite 700, Washington, DC.
\5\ Available from Books and Open-File Reports Section, U.S. Geological Survey, Federal Center, Box 25425, Denver, CO 80225-0425.
\6\ ``Methods for the Determination of Inorganic Substances in Environmental Samples'', EPA-600/R-93-100, August 1993. Available at NTIS, PB94-121811.
\7\ The procedure shall be done in accordance with the Technical Bulletin 601 ``Standard Method of Test for Nitrate in Drinking Water'', July 1994, PN
  221890-001, Analytical Technology, Inc. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5
  U.S.C. 552(a) and 1 CFR Part 51. Copies may be obtained from ATI Orion, 529 Main Street, Boston, MA 02129. Copies may be inspected at EPA's Drinking
  Water Docket, 401 M Street, S.W., Washington, DC 20460; or at the Office of the Federal Register, 800 North Capitol Street, N.W., Suite 700,
  Washington, DC.
\8\ Method B-1011, ``Waters Test Method for Determination of Nitrite/Nitrate in Water Using Single Column Ion Chromatography'', Millipore Corporation,
  Water Chromatography Division, 34 Maple Street, Milford, MA 01757.

[[Page 15041]]


\9\ Method 100.1, ``Analytical Method for Determination of Asbestos Fibers in Water'', EPA-600/4-83-043, EPA, September 1983. Available at NTIS, PB83-
  260471.
\10\ Method 100.2, ``Determination of Asbestos Structure Over 10 m in Length in Drinking Water'', EPA-600/R-94-134, June 1994. Available at
  NTIS, PB94-201902.
\11\ The procedures shall be done in accordance with the Industrial Method No. 129-71W, ``Fluoride in Water and Wastewater'', December 1972, and Method
  No. 380-75WE, ``Fluoride in Water and Wastewater'', February 1976, Technicon Industrial Systems. This incorporation by reference was approved by the
  Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. Copies may be obtained from the Technicon Industrial Systems,
  Tarrytown, NY 10591. Copies may be inspected at EPA's Drinking Water Docket, 401 M Street, S.W., Washington, DC 20460; or at the Office of the Federal
  Register, 800 North Capitol Street, N.W., Suite 700, Washington, DC.
\12\ Unfiltered, no digestion or hydrolysis.
\13\ Methods published by this organization and approved for use under this part may not be modified beyond the modifications expressly allowed and
  defined.

* * * * *
    4. Section 141.24, paragraph (e), is proposed to be amended by
revising the table to read as follows:

Sec. 141.24  Organic chemicals other than total trihalomethanes,
sampling and analytical requirements.

* * * * *
    (e) * * *

                           Table 141.24(e).--List of Approved Organic Test Procedures
----------------------------------------------------------------------------------------------------------------
                                                                                  Other approved methods
                                                                         ---------------------------------------
                   Parameter/methodology                      Reference                   Standard
                                                               method          EPA      method 18th     Other
                                                                                           Ed.\1\
----------------------------------------------------------------------------------------------------------------
1. Benzene
    GC/ELCD...............................................         502.2
    GC/MS.................................................         524.2
2. Carbon Tetrachloride
    GC/ELCD...............................................         502.2
    GC/MS.................................................         524.2
    GC/ECD................................................         551
3. Chlorobenzene
    GC/ELCD...............................................         502.2
    GC/MS.................................................         524.2
4. 1,2-Dichlorobenzene
    GC/ELCD...............................................         502.2
    GC/MS.................................................         524.2
5. 1,4-Dichlorobenzene
    GC/ELCD...............................................         502.2
    GC/MS.................................................         524.2
6. 1,2-Dichloroethane
    GC/ELCD...............................................         502.2
    GC/MS.................................................         524.2
7. cis-Dichloroethylene
    GC/ELCD...............................................         502.2
    GC/MS.................................................         524.2
8. Trans-Dichloroethylene
    GC/ELCD...............................................         502.2
    GC/MS.................................................         524.2
9. Dichloromethane
    GC/ELCD...............................................         502.2
    GC/MS.................................................         524.2
10. 1,2-Dichloropropane
    GC/ELCD...............................................         502.2
    GC/MS.................................................         524.2
11. Ethylbenzene
    GC/ELCD...............................................         502.2
    GC/MS.................................................         524.2
12. Styrene
    GC/ELCD...............................................         502.2
    GC/MS.................................................         524.2
13. Tetrachloroethylene
    GC/ELCD...............................................         502.2
    GC/MS.................................................         524.2
    GC/ECD................................................         551
14. 1,1,1-Trichloroethane
    GC/ELCD...............................................         502.2
    GC/MS.................................................         524.2
    GC/ECD................................................         551
15. Trichloroethylene
    GC/ELCD...............................................         502.2
    GC/MS.................................................         524.2
    GC/ECD................................................         551
16. Toluene
    GC/ELCD...............................................         502.2

[[Page 15042]]


    GC/MS.................................................         524.2
17. 1,2,4-Trichlorobenzene
    GC/ELCD...............................................         502.2
    GC/MS.................................................         524.2
18. 1,1-Dichloroethylene
    GC/ELCD...............................................         502.2
    GC/MS.................................................         524.2
19. Vinyl chloride
    GC/ELCD...............................................         502.2
    GC/MS.................................................         524.2
20. Xylenes (total)                                         ............         515.1
    GC/ELCD...............................................         502.2
    GC/MS.................................................         524.2
21. 2,3,7,8-TCDD (dioxin)                                   ............         515.1
    GC/MS.................................................        1613
22. 2,4-D
    GC/ECD................................................         515.2
    HPLC/UV...............................................         555
23. 2,4,5-TP (Silvex)
    GC/ECD................................................         515.2
    HPLC/UV...............................................         555
24. Alachlor
    GC/NPD................................................         507
    GC/ECD................................................         508.1         505
    GC/MS.................................................         525.2
25. Atrazine
    GC/NPD................................................         507
    GC/ECD................................................         508.1         505
    GC/MS.................................................         525.2
26. Benzo(a)pyrene
    GC/MS.................................................         525.2
    HPLC/Fl-UV............................................         550.1         550           6610
27. Carbofuran
    HPLC/Fl...............................................         531.1
28. Chlordane
    GC/NPD................................................         507
    GC/ECD................................................         508.1         505
    GC/MS.................................................         525.2
29. Dalapon
    GC/ECD................................................         515.1         552.1
30. Di-(2-ethylhexyl) adipate
    GC/PID................................................         506
    GC/MS.................................................         525.2
31. Di-(2-ethylhexyl) phthalate
    GC/PID................................................         506
    GC/MS.................................................         525.2
32. Dibromochloropropane (DBCP)
    GC/ECD................................................         504.1         551
33. Dinoseb
    GC/ECD................................................         515.2         515.1
    HPLC/UV...............................................         555
34. Diquat
    HPLC/UV...............................................         549.1
35. Endothall
    GC/MS.................................................         548.1
36. Endrin
    GC/NPD................................................         507
    GC/ECD................................................         508.1         505
    GC/MS.................................................         525.2
37. Ethylene Dibromide (EDB)
    GC/ECD................................................         504.1         551
38. Glyphosate
    HPLC/Fl...............................................         547                         6651
39. Heptachlor
    GC/ECD................................................         508.1    505, 508
    GC/MS.................................................         525.2
40. Heptachlor Epoxide
    GC/ECD................................................         508.1    505, 508

[[Page 15043]]


    GC/MS.................................................         525.2
41. Hexachlorobenzene
    GC/ECD................................................         508.1    505, 508
    GC/MS.................................................         525.2
42. Hexachlorocyclopentadiene
    GC/ECD................................................         508.1    505, 508
    GC/MS.................................................         525.2
43. Lindane
    GC/ECD................................................         508.1    505, 508
    GC/MS.................................................         525.2
44. Methoxychlor
    GC/ECD................................................         508.1    505, 508
    GC/MS.................................................         525.2
45. Oxamyl
    HPLC/Fl...............................................         531.1                       6610
46. PCBs
    GC/ECD, As decachlorobiphenyl.........................        508A
    GC/ECD, As Aroclors...................................         508           505
47. Pentachlorophenol                                                            515.1
    GC/ECD................................................         515.2
    HPLC/UV...............................................         555
    GC/MS.................................................         525.2
48. Picloram                                                ............         515.1
    GC/ECD................................................         515.2
    HPLC/UV...............................................         555
49. Simazine                                                ............         505
    GC/NPD................................................         507
    GC/ECD................................................         508.1
    GC/MS.................................................         525.2
50. Toxaphene                                               ............         505
    GC/ECD................................................         508
    GC/MS.................................................         525.2
51. Total Trihalomethanes
    GC/ELCD...............................................         502.2
    GC/MS.................................................         524.2
    GC/ECD................................................         551
----------------------------------------------------------------------------------------------------------------
\1\ Methods published by this organization and approved for use under this part may not be modified beyond the
  modifications expressly allowed and defined in each method.

 Note: The following acronyms are used in this table:
    ECD--Electron Capture Detector.
    ELCD--Electrolytic Conductivity Detector.
    Fl--Fluorescence.
    GC--Gas Chromatography.
    GC/MS--Gas Chromatography/Mass Spectrometry.
    HPLC--High Performance Liquid Chromatography.
    NPD--Nitrogen Phosphorous Detector.
    PID--Photoionization Detector.
    UV--Ultraviolet Detector.

* * * * *
    5. Section 141.27 is proposed to be revised to read as follows:

Sec. 141.27  New and alternate analytical methods.

    (a) Sample preservation procedures, container materials, and
maximum allowable holding times for contaminants cited in tables in
Secs. 141.23(k)(1), 141.24(e) and 141.40(n)(11) are prescribed in these
methods except as specified in the table in Sec. 141.23(k)(2). Any
person may apply for a variance from the prescribed preservation
techniques, container materials, and maximum holding times applicable
to samples collected from a public water system (PWS) supply or tap
water. An application for a variance may be made by letter to the
Regional Administrator in the Region in which the water supply system
is located. Sufficient data should be provided to ensure such variance
does not adversely affect the integrity of the sample. Such data will
be forwarded by the Regional Administrator to the Director of the
Analytical Methods Staff for technical review and recommendations for
action on the variance application. Upon receipt of a recommendation
from the Director of the Analytical Methods Staff, the Administrator
may grant a variance applicable to samples collected from the specific
PWS for which the application for variance was made. A decision to
recommend approval or denial of a variance will be made within 90 days
of receipt of a complete application.
    (b) A reference method listed in the tables in Secs. 141.23(k)(1),
141.24(e), and 141.40(n)(11) of this section may be modified to improve
separations, lower the costs of measurements, reduce or eliminate
interferences, or for other purposes, provided that the modification is
not explicitly prohibited in the reference method and provided

[[Page 15044]]

that the laboratory modifying the reference method meets the
requirements in this section, performs the standardized QC tests, and
demonstrates that the QC acceptance criteria and the requirements
specified at Appendixes E, F, and G of 40 CFR part 136 are met. A
laboratory that wishes to use a new or modified drinking water method
must demonstrate that the MDL determined with that method meets the
detection limits specified at Secs. 141.23, 141.24 and 141.89 and/or at
Sec. 141.27(d). Demonstration of a valid detection limit requires use
of an MDL study in accordance with the procedure at 40 CFR part 136,
Appendix B. If the MDL determined with the new or modified method is
not acceptable, the method may not be used. Specified detection limits
are usually analyte-specific. For any given analyte, the specified
detection limit may vary between a wastewater and a drinking water
reference method.
    (1) Tier 1: modification of a reference method for application in a
single laboratory to one or more PWSs.
    (i) Application to a single PWS.
    (A) A laboratory may modify a reference method listed in the tables
in Secs. 141.23(k)(1), 141.24(e) and 141.40(n)(11) of this section for
determination of an analyte of concern in a specific PWS, provided that
the laboratory:
    (1) Performs the standardized QC tests, including a test of initial
precision and recovery (IPR) on a reagent water matrix;
    (2) Performs the matrix spike (MS) and matrix spike duplicate (MSD)
tests on a sample from the PWS to which the modification is to be
applied;
    (3) Meets the QC acceptance criteria in the reference method as
supplemented in the table of QC acceptance criteria for drinking water
methods at Sec. 141.27(d);
    (4) Documents the results of the QC tests using the Checklist for
Initial Demonstration of Method Performance and the Checklist for
Continuing Demonstration of Method Performance which are specified in
40 CFR part 136, Appendix E; and
    (5) Maintains the results of the QC tests and other tests on file
for inspection by EPA and/or the State.
    (B) After the laboratory has demonstrated application of a method
modification to a given PWS by meeting the MS/MSD QC acceptance
criteria, only that laboratory may subsequently apply that method
modification to samples from that PWS.
    (C) A laboratory may apply a given method modification to
additional PWSs if the laboratory validates the modification on a
sample from each PWS by performing a matrix spike (MS) and matrix spike
duplicate (MSD) test and meeting the MS/MSD QC acceptance criteria for
precision and recovery for each PWS.
    (ii) Application to multiple public water systems (PWSs). After a
laboratory has validated a given modification on samples from a minimum
of three (3) PWSs in accordance with the procedures given in paragraph
(b)(1)(i)(A) of this section, the laboratory may subsequently apply
that method modification to other PWSs, provided that the matrix spike
(MS) and matrix spike duplicate (MSD) recovery and the relative percent
difference are within the QC acceptance criteria given for the analyte
in the reference method as supplemented by the applicable QC acceptance
criteria for drinking water methods at Sec. 141.27(d). If all QC
acceptance criteria are not met for a sample from a given PWS, the
modification may not be applied to samples from that PWS.
    (iii) To test the modified method for potential matrix effects, the
three (3) PWS samples must be collected from PWSs with water quality
characteristics that are sufficiently different that sample matrix
effects, if any, can be observed. In all cases, the laboratory must try
to determine if the measurement result for the target analyte using a
new or modified method differs from the result obtained in a reagent
water matrix or in a previously validated matrix type or PWS sample.
Selection of suitable PWSs requires a knowledge of the chemistry of the
method. Analysts may review an applicable approved or published method
for indications of matrix effects that are unique to the analyte
separation and measurement technologies used in the new or modified
method. Water quality characteristics that can affect analysis of
drinking water samples include, but are not limited to pH, total
organic carbon content, turbidity, total organic halogen content, ionic
strength, sulfate contamination, metal contamination, and
trihalomethane contamination of the drinking water sample.
    (2) Tier 2: modification of a reference method for application by
all laboratories to all PWSs in the water supply and distribution
industry (nationwide modification).
    (i) A person may modify a reference method for application by all
laboratories to determination of an analyte of concern in sample
matrices from any PWS provided that the modification is validated in a
minimum of three (3) laboratories each of which test a sample from each
of three (3) different PWS for a minimum of nine (9) tests. To test the
modified method for potential matrix effects, the three (3) PWS samples
must be collected from PWSs with sufficiently different water quality
characteristics according to criteria specified at paragraph
(b)(1)(iii) of this section. Each laboratory must meet the requirements
in paragraph (b)(1)(i)(A) of this section. After the tests in all three
laboratories have met all QC acceptance criteria for the reference
method, the modified method may be applied by laboratories nationwide
to PWSs in the water supply and distribution industry.
    (ii) A person who modifies a reference method and validates the
method modification under Tier 2 may submit that modification to EPA
for a letter of approval. The information that must be submitted
includes the results of the performance tests required by paragraph
(b)(1)(i)(A) of this section. This information and other information
that must be submitted and the format for submission are specified at
40 CFR part 136, Appendixes E, F, and G.
    (iii) A person who modifies a reference method and validates the
method modification under Tier 2 may submit that modification to EPA
for approval and inclusion in a table in this part 141. The information
that must be submitted includes the results of the performance tests
required by paragraph (b)(1)(i)(A) of this section. This information
and other detailed information that must be submitted and the format
for submission are specified at 40 CFR part 136, Appendixes E, F, and
G.
    (iv) A decision to recommend proposal of a Tier 2 method
modification will be made by the Director of the Analytical Methods
Staff within 90 days of receipt of a complete application.
    (c) A person may apply to EPA for use of a new method for
determination of an analyte of concern, provided that the new method
meets the requirements for validation and format as specified in this
section and in 40 CFR part 136, Appendixes E, F, and G.
    (1) The new method must demonstrate an acceptable MDL for each
analyte as specified in Sec. 141.27(b).
    (i) A new method must:
    (A) Be documented in accordance with requirements in 40 CFR part
136, Appendixes E, F, and G.
    (B) Contain standardized QC as defined at Sec. 141.2.
    (C) Contain QC acceptance criteria that have been developed in
accordance

[[Page 15045]]

with the requirements detailed in 40 CFR part 136, Appendixes E, F, and
G.
    (D) Employ a determinative technique for an analyte of concern with
selectivity or sensitivity equal or superior to the selectivity or
sensitivity of the determinative technique in any approved method, and
that differs from the determinative techniques employed for that
analyte in all approved methods.
    (E) Be accompanied by the information specified at 40 CFR part 136,
Appendix G.
    (ii) A decision to recommend proposal of a new method will be made
by the Director of the Analytical Methods Staff within 90 days of
receipt of a complete application.
    (2) Tier 1: application of a new method by a single laboratory to
one or more PWSs.
    (i) A person may develop a new method for determination of an
analyte of concern by a single laboratory by validating the method and
developing QC acceptance criteria from an interlaboratory method
validation study or from a single-laboratory validation study on a
drinking water sample. Details of the single-laboratory method
validation study and development of QC acceptance criteria from a
single-laboratory or interlaboratory method validation study are
specified at paragraph (b)(1) of this section and at 40 CFR part 136,
Appendix E.
    (ii) A person who develops a new method under Tier 1 must submit
the method to EPA for a letter of approval. The information that must
be submitted and the format for submission are specified at 40 CFR part
136, Appendixes E, F, and G.
    (3) Tier 2: application of a new method by all laboratories to all
PWSs in the water supply and distribution industry (nationwide use).
    (i) A person may develop a new method for determination of an
analyte of concern in all PWSs in the water supply and distribution
industry by developing QC acceptance criteria from an interlaboratory
method validation study or from multiple, single-laboratory validation
studies as specified in the Streamlining Guide, and by validating the
new method in a minimum three (3) laboratories each of which test
samples from a minimum of three (3) different PWS for a minimum of nine
(9) tests. In the method validation study, each laboratory will test
all of the samples from the same set of PWS samples and this set will
contain samples from a minimum of three (3) different PWSs. To test the
modified method for potential matrix effects, the three (3) PWS samples
must be collected from PWSs with sufficiently different water quality
characteristics according to criteria specified at paragraph (b)(2) and
(b)(1)(iii) of this section.
    (ii) A person who develops a new method under Tier 2 must submit
the method to EPA for approval and inclusion in a table in this part
141. The information that must be submitted includes the results of the
performance tests required by paragraph (b)(2)(i) of this section. This
information and other detailed information that must be submitted and
the format for submission are specified at 40 CFR part 136, Appendixes
E, F, and G.
    (d) Standardized QC and QC acceptance criteria for modifications of
inorganic contaminant reference methods at Sec. 141.23(k)(1) of this
section are as follows:

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[[Page 15049]]

    (e) The number and type of required tests, testing laboratories,
matrices, and replicate QC tests for method validation depend on the
tier at which the new or modified wastewater or drinking water method
is validated. These requirements are specified at paragraphs (a), (b),
(c) of this section and in the table at Sec. 136.5(d).
    6. Section 141.40, paragraph (n)(11), is proposed to be amended by
revising the table to read as follows:

Sec. 141.40  Special monitoring for inorganic and organic contaminants.

* * * * *
    (n) * * *
    (11) * * *

                                               Table 141.40(n)(11)
----------------------------------------------------------------------------------------------------------------
                                                                                  Other approved methods
                                                                         ---------------------------------------
                   Parameter/methodology                      Reference                   Standard
                                                               method          EPA        methods       Other
                                                                                        18th ed.\1\
----------------------------------------------------------------------------------------------------------------
1. aldicarb
    HPLC/Fl                                                        531.1                       6610
2. aldicarb sulfone
    HPLC/Fl                                                        531.1                       6610
3. aldicarb sulfoxide
    HPLC/Fl                                                        531.1                       6610
4. aldrin
    GC/ECD                                                         508.1    505, 508
    GC/MS                                                          525.2
5. butachlor
    GC/MS                                                          525.2
    GC/NPD                                                         507
6. carbaryl
    HPLC/Fl                                                        531.1                       6610
7. dicamba
    GC/ECD                                                         515.2         515.1
    HPLC
12. metribuzin
    GC/ECD                                                         508.1
    GC/MS                                                          525.2
    GC/NPD                                                         507
13. propachlor
    GC/ECD                                                         508.1         508
    GC/MS                                                          525.2
----------------------------------------------------------------------------------------------------------------
Note: The following acronyms are used in this table:
    ECD--Electron Capture Detector.
    Fl--Fluorescence.
    GC--Gas Chromatography.
    GC/MS--Gas Chromatography/Mass Spectrometry.
    HPLC--High Performance Liquid Chromatography.
    NPD--Nitrogen Phosphorous Detector.
    UV--Ultraviolet Detector.

* * * * *
[FR Doc. 97-7221 Filed 3-27-97; 8:45 am]
BILLING CODE 6560-50-P

 
 

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