[Federal Register Volume 70, Number 198 (Friday, October 14, 2005)]
[Rules and Regulations]
[Pages 60134-60198]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 05-20001]



[[Page 60133]]

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Part II





Environmental Protection Agency





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40 CFR Parts 9, 122, and 403



Streamlining the General Pretreatment Regulations for Existing and New 
Sources of Pollution; Final Rule



Availability of and Procedures for Removal Credits; Proposed Rule

Federal Register / Vol. 70, No. 198 / Friday, October 14, 2005 / 
Rules and Regulations

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 9, 122 and 403

[OW-2002-0007; FRL-7980-4]
RIN 2040-AC58


Streamlining the General Pretreatment Regulations for Existing 
and New Sources of Pollution

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: Today's final rule revises several provisions of the General 
Pretreatment Regulations that address requirements for, and oversight 
of, Industrial Users who introduce pollutants into Publicly Owned 
Treatment Works (POTWs). This final rule includes changes to certain 
program requirements to be consistent with National Pollutant Discharge 
Elimination System (NPDES) requirements for direct dischargers to 
surface waters. Today's action will reduce the regulatory burden on 
both Industrial Users and State and POTW Control Authorities without 
adversely affecting environmental protection and will allow Control 
Authorities to better focus oversight resources on Industrial Users 
with the greatest potential for affecting POTW operations or the 
environment.

DATES: This regulation is effective November 14, 2005. For judicial 
review purposes, this final rule is promulgated as of 1 p.m. (Eastern 
Time) on October 28, 2005, as provided at 40 CFR 23.2.

ADDRESSES: EPA has established a docket for this action under Docket ID 
No. OW-2002-0007. All documents in the docket are listed in the EDOCKET 
index at http://www.epa.gov/edocket. Although listed in the index, some 
information is not publicly available, i.e., CBI or other information 
whose disclosure is restricted by statute. Certain other material, such 
as copyrighted material, is not placed on the Internet and will be 
publicly available only in hard copy form. Publicly available docket 
materials are available either electronically in EDOCKET or in hard 
copy at the EPA Docket Center, EPA/DC, EPA West, Room B102, y1301 
Constitution Ave., NW, Washington, DC. The Public Reading Room is open 
from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding legal 
holidays. The telephone number for the Public Reading Room is (202) 
566-1744, and the telephone number for the Water Docket Office is (202) 
566-2426).

FOR FURTHER INFORMATION CONTACT: Jan Pickrel, Water Permits Division, 
Office of Wastewater Management, Office of Water, (4203), Environmental 
Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460; 
telephone number: 202-564-7904, e-mail address: <a href="/cdn-cgi/l/email-protection#85f5ece6eef7e0e9abefe4ebc5e0f5e4abe2eaf3"><span class="__cf_email__" data-cfemail="92e2fbf1f9e0f7febcf8f3fcd2f7e2f3bcf5fde4">[email protected]</span></a>. 
Greg Schaner, Water Permits Division, Office of Wastewater Management, 
Office of Water, (4203), Environmental Protection Agency, 1200 
Pennsylvania Ave., NW., Washington, DC 20460; telephone number: 202-
564-0721, e-mail address: <a href="/cdn-cgi/l/email-protection#20534348414e45520e47524547604550410e474f56"><span class="__cf_email__" data-cfemail="e794848f86898295c980958280a7829786c9808891">[email protected]</span></a>.

SUPPLEMENTARY INFORMATION: Information in this preamble is organized as 
follows:

    A. General Information
    1. Does This Final Rule Apply to Me?
    2. How Can I Get Copies of This Document and Other Related 
Information?
    3. What Process Governs Judicial Review of This Rule?
    B. Under What Legal Authority Is This Final Rule Issued?
    C. How Is This Preamble Organized?
    D. What Is The Comment Response Document?
    E. What Other Information Is Available To Support This Final 
Rule?
I. Background Information
II. How Was This Final Rule Developed?
III. Description of Final Rule Actions
    A. Sampling for Pollutants Not Present (40 CFR 403.8(f)(2)(v) 
and 403.12(e))
    B. General Control Mechanisms (40 CFR 403.8(f)(1)(iii))
    C. Best Management Practices (40 CFR 403.5, 403.8(f) and 
403.12(b), (e), and (h))
    D. Slug Control Plans (40 CFR 403.8(f)(1)(iii)(B)(6) and 
403.8(f)(2)(vi))
    E. Equivalent Concentration Limits for Flow-Based Standards (40 
CFR 403.6(c)(6))
    F. Use of Grab and Composite Samples (40 CFR 403.12(b), (d), 
(e), (g), and (h))
    G. Significant Noncompliance Criteria (40 CFR 403.8(f)(2)(viii))
    H. Removal Credits--Compensation for Overflows (40 CFR 403.7(h))
    I. Miscellaneous Changes (40 CFR 403.12(g), (j), (l), and (m))
    J. Equivalent Mass Limits for Concentration Limits (40 CFR 
403.6(c)(5))
    K. Oversight of Categorical Industrial Users (40 CFR 403.3(v), 
403.8(f)(2)(v), and 403.12(e), (g), (i), (q))
IV. Description of Areas Where EPA Is Not Taking Action on the 
Proposed Rule
    A. Specific Prohibition Regarding pH (40 CFR 403.5(b)(2))
V. Changes to part 122
VI. Considerations in Adopting Today's Rule Revisions
VII. Regulatory Requirements
    A. Executive Order 12866: Regulatory Planning and Review
    B. Paperwork Reduction Act
    C. Regulatory Flexibility Act
    D. Unfunded Mandates Reform Act
    E. Executive Order 13132: Federalism
    F. Executive Order 13175: Consultation and Coordination with 
Indian Tribal Governments
    G. Executive Order 13045: Protection of Children from 
Environmental Health Risks and Safety Risks
    H. Executive Order 13211: Actions That Significantly Affect 
Energy Supply, Distribution, or Use
    I. National Technology Transfer and Advancement Act
    J. Congressional Review Act

A. General Information

1. Does this final rule apply to me?

    Entities potentially affected by this action are governmental 
entities responsible for implementation of the National Pretreatment 
Program and industrial facilities subject to Pretreatment Standards and 
Requirements. These entities include:

------------------------------------------------------------------------
           Category                  Examples of regulated entities
------------------------------------------------------------------------
Local government.............  Publicly Owned Treatment Works.
State government.............  States and Tribes acting as Pretreatment
                                Program Control Authorities or as
                                Approval Authorities.
Industry.....................  Industrial Users of POTWs.
Federal Government...........  EPA Regional Offices acting as
                                Pretreatment Program Control Authorities
                                or as Approval Authorities.
------------------------------------------------------------------------

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 or facility is regulated by this action, you should 
carefully examine the applicability criteria in 40 CFR 403.3, 403.5, 
403.6, 403.7, 403.8, 403.12, and 403.15 of Part 403 of Title 40 of the 
Code of Federal Regulations.

[[Page 60135]]

If you have questions about the applicability of this action to a 
particular entity, consult the person listed in the preceding FOR 
FURTHER INFORMATION CONTACT section.

2. How can I get copies of this document and other related information?

    a. Docket. EPA has established an official public docket for this 
action under Docket ID No. W-00-27. The official public docket consists 
of the documents specifically referenced in this action, any public 
comments received, and other information related to this action. 
Although a part of the official docket, the public docket does not 
include Confidential Business Information (CBI) or other information 
whose disclosure is restricted by statute. The official public docket 
is the collection of materials that is available for public viewing at 
the Water Docket in the EPA Docket Center, (EPA/DC) EPA West, Room 
B102, 1301 Constitution Ave., NW., Washington, DC. The EPA Docket 
Center Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday 
through Friday, excluding legal holidays. The telephone number for the 
Reading Room is (202) 566-1744, and the telephone number for the Water 
Docket is (202) 566-2426.
    b. Electronic Access. You may access this Federal Register document 
electronically through the EPA Internet under the ``Federal Register'' 
listings at http://www.epa.gov/fedrgstr/ or at the ``Pretreatment'' 
page at http://cfpub.epa.gov/npdes/home.cfm?program_id=3.
    An electronic version of the public docket is available through 
EPA's electronic public docket and comment system, EPA Dockets. You may 
use EPA Dockets at http://www.epa.gov/edocket/ to view public comments, 
access the index listing of the contents of the official public docket, 
and to access those documents in the public docket that are available 
electronically. Although not all docket materials may be available 
electronically, you may still access any of the publicly available 
docket materials through the docket facility identified in section 
A.2.a. Once in the system, select ``search'', then key in the 
appropriate docket identification number (OW-2002-0007).

3. What process governs judicial review of this rule?

    Under Section 509(b)(1) of the Clean Water Act (CWA), judicial 
review of today's rule may be obtained by filing a petition for review 
in the United States Circuit Court of Appeals within 120 days from the 
date of promulgation of this rule. For judicial review purposes, this 
final rule is promulgated as of 1 p.m. (Eastern time) on October 28, 
2005 as provided at 40 CFR 23.2. Under section 509(b)(2) of the CWA, 
the requirements of this regulation may not be challenged later in 
civil or criminal proceedings brought by EPA to enforce these 
requirements.

B. Under What Legal Authority Is This Final Rule Issued?

    Today's final rule is issued under the authority of Sections 101, 
208(b)(2) (C)(iii), 301(b)(1)(A)(ii), 301(b)(2)(A)(ii), 301(h)(5) and 
301(i)(2), 304(e) and (g), 307, 308, 309, 402(b), 405, and 501(a) of 
the Federal Water Pollution Control Act as amended.

C. How is This Preamble Organized?

    There is an outline for the preamble to today's final rule in the 
opening of this SUPPLEMENTARY INFORMATION section. For each distinct 
issue of the final rule, the preamble is written in a question-and-
answer format that is designed to help the reader understand the 
information in the rule. Under each issue, there are subsections that 
provide the context for the final rule, including a discussion of the 
rules in place prior to today's rulemaking, the changes that were 
proposed, the changes that are being finalized (including significant 
differences from the proposal), and a summary of major comments and EPA 
response.

List of Acronyms

BAT--best available technology economically achievable
BCT--best conventional pollutant control technology
BOD--biochemical oxygen demand
BPJ--best professional judgment
BMP--Best Management Practice
BPT--best practicable control technology currently available
CIU--Categorical Industrial User
CFR--Code of Federal Regulations
CWA--Clean Water Act
ELG--effluent limitations guideline
EMS--environmental management system
EPA--Environmental Protection Agency
EQIP--Environmental Quality Incentives Program
FR--Federal Register
ICR--Information Collection Request
IU--Industrial User
NODA--Notice of Data Availability
NOI--notice of intent
NPDES--National Pollutant Discharge Elimination System
NSCIU--Non-Significant Categorical Industrial User
NTTAA--National Technology Transfer and Advancement Act
OMB--U.S. Office of Management and Budget
POTW--Publicly Owned Treatment Works
PSES--Pretreatment Standards for Existing Sources
RFA--Regulatory Flexibility Act
SBA--U.S. Small Business Administration
SBAR (panel)--Small Business Advocacy Review Panel
SBREFA--Small Business Regulatory Enforcement Fairness Act
SIU--Significant Industrial User
SNC--Significant Noncompliance
SRF--State Revolving Fund
UMRA--Unfunded Mandates Reform Act
WWTP--wastewater treatment plant

D. What Is the Comment Response Document?

    EPA received more than 220 comments on the proposed rule. EPA 
evaluated all the significant comments submitted and prepared a Comment 
Response Document containing the Agency's responses to those comments. 
The Comment Response Document complements and supplements this preamble 
by providing more detailed explanations of EPA's final actions. The 
Comment Response Document is available at the Water Docket. See Section 
E below for additional information.

E. What Other Information Is Available To Support This Final Rule?

    In addition to this preamble, today's final rule is supported by 
other information that is part of the administrative record, such as 
the Comment Response Document, and the key supporting documents listed 
below. These supporting documents and the administrative record are 
available at the Water Docket and via e-Docket:
    <bullet> Information Collection Request
    <bullet> Past EPA guidance manuals and policy documents
    <bullet> Stakeholder communications
    <bullet> EPA data collected in support of this rulemaking

I. Background Information

A. What Is the National Pretreatment Program?

    The National Pretreatment Program is part of the Clean Water Act 
(CWA)'s water pollution control program. The program is a joint 
regulatory effort by local, state, and Federal authorities that require 
the control of industrial and commercial sources of pollutants 
discharged to municipal wastewater plants (called ``Publicly Owned 
Treatment Works'' or ``POTWs''). Control of pollutants prior to 
discharge of wastewater to the sewer minimizes

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the possibility of pollutants interfering with the operation of the 
POTW and reduces the levels of toxic pollutants in wastewater 
Discharges from the POTW and in the sludge resulting from municipal 
wastewater treatment.
    The Pretreatment Program is a core part of the CWA's National 
Pollutant Discharge Elimination System (NPDES) program, and it has 
helped communities:
    <bullet> Maintain and restore watershed quality;
    <bullet> Encourage pollution prevention;
    <bullet> Increase beneficial uses of sewage sludge;
    <bullet> Prevent formation of poisonous gases in the sanitary sewer 
system;
    <bullet> Meet wastewater Discharge standards; and
    <bullet> Institute emergency-prevention measures.

B. What Regulation Is EPA Revising?

    EPA is today streamlining and clarifying various provisions of the 
General Pretreatment Regulations for Existing and New Sources of 
Pollution codified at 40 CFR Part 403. The CWA directs EPA to develop 
regulations in order to control pollutants which may pass through or 
interfere with POTW treatment processes or contaminate sewage sludge. 
On June 26, 1978, EPA promulgated the General Pretreatment Regulations, 
which established standards and procedures for controlling the 
introduction of wastes into POTWs (43 FR 27736). There have been a 
number of revisions to the General Pretreatment Regulations. The last 
major revisions were to implement improvements arising from the 
Domestic Sewage Study (Report to Congress on the Discharge of Hazardous 
Wastes to Publicly Owned Treatment Works) (55 FR 30082, July 24, 1990).
    The General Pretreatment Regulations require POTWs that meet 
certain criteria to develop Pretreatment programs to control industrial 
Discharges into their sewage collection systems. These programs must be 
approved by either EPA or states acting as the Pretreatment ``Approval 
Authority.'' More than 1,400 POTWs have developed Approved Pretreatment 
Programs pursuant to the regulations in 40 CFR 403.8. These POTWs act 
as the Pretreatment ``Control Authority'' with respect to the 
Industrial Users that discharge to their systems. In the absence of an 
approved POTW Pretreatment Program, the State or EPA Approval Authority 
serves as the Control Authority.
    Industrial Users of POTWs must comply with Pretreatment Standards 
prior to introducing pollutants into a POTW. POTWs are required to 
impose ``local limits'' to prevent Pass Through and Interference from 
the pollutants discharged into their systems. The General Pretreatment 
Regulations also include general prohibitions that forbid Industrial 
Users from causing Pass Through and Interference, and specific 
prohibitions against the discharge of pollutants that cause problems at 
the POTW such as corrosion, fire or explosion, and danger to worker 
health and safety. EPA has also developed National categorical 
Pretreatment Standards that apply numeric pollutant limits to 
Industrial Users in specific industrial categories. The General 
Pretreatment Regulations include reporting and other requirements 
necessary to implement these categorical Standards (40 CFR 403.12 (b)).
    Today's final rule modifies several provisions of the existing 
Pretreatment Regulations. The rule includes a variety of changes which 
will be described further in Section E.

C. Why Is EPA Revising the Existing General Pretreatment Regulations?

    By finalizing today's rule, EPA is working to improve the National 
Pretreatment Program to protect public health and the environment, 
while maintaining or improving the program's effectiveness. Although 
adoption of the General Pretreatment Regulations has resulted in more 
consistent implementation of the Pretreatment program on a national 
basis, many individual POTWs and Industrial Users have experienced 
problems implementing various requirements.
    EPA's objective in finalizing today's streamlining regulation is to 
achieve better environmental results at a lower cost by allowing 
Control Authorities to better focus oversight resources where they will 
do the most good. The revisions in today's final rule achieve this 
objective by reducing the burden of technical and administrative 
requirements that EPA has determined provide minimal environmental 
benefit but consume significant resources of Industrial Users, and POTW 
and state Control Authorities. In designing these revisions, EPA took 
care to ensure that the changes being finalized do not reduce the 
current environmental protections in place.
    The importance of finalizing today's streamlining rule was 
highlighted in two recent reports. The Office of Management and Budget 
(OMB) included the issuance of the final rule among a list of steps the 
Federal government would take to reduce the cost burden on the 
manufacturing sector. See Regulatory Reform of the U.S. Manufacturing 
Sector (OMB, 2005), which is posted at http://www.whitehouse.gov/omb/inforeg/reports/manufacturing_initiative.pdf. EPA's Office of 
Inspector General (OIG) also recommended that the Office of Water set 
milestones for finalizing this streamlining rule as part of a broader 
effort to improve the effectiveness of the National Pretreatment 
Program. See Recommendation <greek-i> 4.2 of EPA Needs to Reinforce Its 
National Pretreatment Program (OIG, Report 2004-P-00030, September 
2004), posted at http://www.epa.gov/oig/reports/2004/20040928-2004-P-00030.pdf.

D. What Are the Roles of Key Entities Involved in the Final Rule?

    EPA recognizes the role of many interested parties in the 
development of, and, ultimately, the successful implementation of this 
final rule. To the greatest extent possible, EPA has attempted to 
strike a reasonable balance among the many interests. A short summary 
of their roles is provided below.
    1. POTWs. Publicly Owned Treatment Works (POTWs) collect wastewater 
from homes, commercial buildings, and industrial facilities and 
transport it via a series of pipes, known as a collection system, to 
the treatment plant. Today, there are an estimated 14,800 POTWs. Most 
POTWs are not designed to treat the toxics in commercial and industrial 
wastes which can cause serious problems. The General Pretreatment 
Regulations require POTWs that meet certain criteria to develop 
Pretreatment programs to control industrial Discharges into their 
sewage collection systems. These POTWs act as the Pretreatment 
``Control Authority'' with respect to the Industrial Users that 
discharge to their systems. POTWs play a key role in the enforcement of 
the Pretreatment program through the development and implementation of 
Enforcement Response Plans.
    2. States. Thirty-four states are authorized to serve as Approval 
Authorities for implementation of the Pretreatment Program. In the 
absence of an Approved POTW Pretreatment Program, the state may serve 
as the Control Authority.
    3. EPA. EPA's statutory responsibility is to establish national 
regulations such as those covering the Pretreatment Program, which 
protect and restore the chemical, physical, and biological integrity of 
the Nation's waters. EPA also develops policy and guidance and provides 
training and oversight for program implementation. EPA's regional 
offices also serve as the Approval Authority for state

[[Page 60137]]

Pretreatment programs, where the state is not authorized to run the 
program, and as the Control Authority for POTWs without an approved 
Pretreatment Program in these states.
    4. Industrial Dischargers. Industrial Users of POTWs must comply 
with Pretreatment Standards prior to introducing pollutants into a 
POTW. The General Pretreatment Regulations include general prohibitions 
that forbid Industrial Users from causing Pass Through and 
Interference, and specific prohibitions against the discharge of 
pollutants that cause problems at the POTW such as corrosion, fire or 
explosion, and danger to worker health and safety.
    EPA has also developed National categorical Pretreatment Standards 
that apply numeric and narrative pollutant limits to Industrial Users 
in specific industrial categories. The General Pretreatment Regulations 
include reporting and other requirements necessary to implement these 
categorical Standards (40 CFR 403.12(b)).
    5. Other stakeholders. Trade associations, professional 
organizations, environmental interest groups, and the public have an 
interest in the Pretreatment of industrial and commercial waste and 
have been involved in this rulemaking through comments and 
participation in stakeholder meetings.

E. What Principles Guided EPA's Decisions in This Rule?

    EPA has considered the implementation of the current General 
Pretreatment Regulations, changes in industry, the comments on the 
proposed rule, and relevant studies, data, and reports in developing 
this final rule. The Agency has tried to ensure this final rule is 
based on sound science, protects existing water quality gains, and is 
consistent with current Pretreatment guidance and policy documents. EPA 
made this final rule as simple and easy to understand as possible, and 
has attempted to provide a clear understanding of who is affected and 
what they are expected to do. The hallmark of this rule is that it 
reduces the burden of compliance with the General Pretreatment 
Regulations, while at the same time protecting the environment.

F. What Are the Major Elements of This Final Rule? Where Do I Find 
Specific Requirements?

    This section provides a summary of the major elements of this final 
rule and a brief index on where each of the requirements is located in 
the final regulations. The rule makes the following changes:
    <bullet> Provides POTWs with the authority to grant monitoring 
waivers to industrial facilities where they document that pollutants 
are not present at the facility or anywhere in the wastestream. EPA 
notes that this authority is already available in the National 
Pollutant Discharge Elimination System (NPDES) regulations for point 
sources discharging directly to surface waters.
    <bullet> Authorizes POTWs to use general control mechanisms (e.g., 
permits) to regulate multiple industrial dischargers that share common 
characteristics.
    <bullet> Clarifies that POTWs can use Best Management Practices 
(BMPs) as an alternative to numeric limits that are developed to 
protect the POTW, water quality, and sewage sludge.
    <bullet> Clarifies certain requirements regarding the frequency of 
on-site industrial facility inspections to evaluate the adequacy of 
controls for ``Slug Discharges''.
    <bullet> Provides greater flexibility in the use of certain 
sampling techniques, and establishes greater consistency with the 
sampling protocols in other parts of EPA's regulations.
    <bullet> Provides the Control Authority with the discretion to 
authorize the use of equivalent concentration limits in lieu of mass 
limits for certain industrial categories, and allows the conditional 
use of equivalent mass limits in lieu of concentration-based limits 
where appropriate to facilitate adoption of new, water-conserving 
technologies.
    <bullet> Authorizes POTWs to establish alternative sampling, 
reporting, and inspection requirements for certain classes of 
categorical Industrial Users (CIUs).
    <bullet> Clarifies the definition of significant noncompliance 
(SNC) as it applies to violations of instantaneous and narrative 
requirements, and late reports, and provides additional options for 
publishing lists of industrial facilities in SNC annually in the 
newspaper. The rule also retains existing rules and policies regarding 
the application of Technical Review Criteria (TRC) and the use of the 
``rolling quarter'' approach in determining SNC status.
    <bullet> Provides updated references relating to requirements that 
POTWs must meet to adjust removal credits for combined sewer overflows 
(CSOs).
    <bullet> Makes other miscellaneous changes designed to maintain 
consistency with the NPDES regulations or to correct typographical 
errors.
    The following table indicates where these changes can be found in 
the General Pretreatment Regulations at 40 CFR part 403.

------------------------------------------------------------------------
                 Issue                     Section of 40 CFR 403 rules
------------------------------------------------------------------------
Sampling for pollutants not present....  403.8(f)(2)(v), 403.12(e)
General control mechanisms.............  403.8(f)(1)(iii)
Best Management Practices..............  403.5, 403.8(f), 403.12(b),
                                          (e), (h)
Slug control plans.....................  403.8(f)(1)(iii)(B)(6),
                                          403.8(f)(2)(vi))
Equivalent concentration limits for      403.6(c)(6)
 flow-based Standards.
Equivalent mass limits for               403.6(c)(5)
 concentration-based Standards.
Use of grab and composite samples......  403.12(b), (d), (e), (g), (h)
Significant noncompliance criteria.....  403.8(f)(2)(viii)
Removal credits........................  403.7(h)
Non-Significant CIU....................  403.3(v)(2), 403.8(f)(2)(v),
                                          (6), 403.12(e)(1), (g), (i),
                                          (q)
Middle Tier CIU........................  403.8(f)(2)(v)(C),
                                          403.12(e)(3), (i)
Miscellaneous changes..................  403.12(g), (j), (l), (m)
------------------------------------------------------------------------

II. How Was This Final Rule Developed?

    EPA initiated this effort in response to a Presidential Report on 
``Reinventing Environmental Regulations'' (March 1995). The Report 
pledged to provide ``more common sense and fairness in our 
regulations'' with an ultimate goal of providing greater flexibility, 
reducing burden, and achieving greater environmental results at less 
cost. In 1995, EPA's Office of Wastewater Management started an 
evaluation of all of the General Pretreatment Regulations in order to 
identify streamlining opportunities. Based on input from various 
stakeholders, EPA developed issue papers that summarized 11 areas

[[Page 60138]]

in which the Pretreatment Regulations might be streamlined.
    In May 1996, the issue papers were distributed to stakeholders 
(States, cities, trade associations, professional organizations, and 
environmental interest groups) for comment. The Agency also considered 
recommendations developed through a joint Association of Metropolitan 
Sewerage Agency (``AMSA'', now the ``National Association of Clean 
Water Agencies'') and Water Environment Federation workshop held in 
1996, which included Pretreatment experts from many stakeholder 
perspectives. In response to comments received on the issue papers and 
the joint workshop's recommendations, EPA prepared a draft proposal and 
preamble and distributed it for comment in May 1997. The proposed rule 
was published in the Federal Register on July 22, 1999 (64 FR 39564).
    EPA received 221 sets of comments on the proposed rule. Comments 
were received from individual POTWs and Industrial Users, trade groups 
representing those interests, states, and one environmental 
organization (the Natural Resources Defense Council). In finalizing 
this rule, EPA carefully reviewed the issues raised in the public 
comments. Due to the intervening time between the proposed and final 
rules, EPA also revisited the major assumptions underlying each rule 
change to verify that these assumptions were still valid. In a few 
areas, this process required research or additional data to support 
certain provisions, and discussions with stakeholders expressing 
continued interest in the rule regarding their comments on the proposed 
rule.

III. Description of Final Rule Actions

    Today's final rule addresses 12 specific issues and a few 
miscellaneous changes pertaining to the General Pretreatment 
Regulations. This section describes the context of these changes, 
records how the proposal and final rule differ, and summarizes EPA's 
rationale for specific actions and how the Agency responded to 
significant comments.
    EPA notes that capitalized terms in this and other sections (e.g., 
categorical Pretreatment Standards, Interference, Pass Through, etc.) 
should signal to the reader that these are terms defined in 40 CFR 
403.3.

A. Sampling for Pollutants Not Present (40 CFR 403.8(f)(2)(v) and 
403.12(e))

    Today's rule allows the Control Authority to authorize an 
Industrial User subject to categorical Pretreatment Standards to forgo 
sampling of a pollutant if the Industrial User demonstrates through 
sampling and a technical evaluation of its facility operations, that a 
given pollutant is neither present nor expected to be present in the 
Discharge, or is only present at background levels from intake water 
without any increase in the pollutant due to the activities of the 
Industrial User. There is similar language in EPA's NPDES permitting 
regulations for direct dischargers. See 40 CFR 122.44(a)(2). The POTW 
Control Authority to which the Industrial User discharges may also 
reduce its monitoring for the pollutant to once during the term of the 
Categorical Industrial User's control mechanism. Note that in the 
discussion of this issue, when EPA uses the phrase ``pollutants not 
present'' it is using this phrase as short-hand for ``pollutants 
neither present nor expected to be present above background levels''. 
In addition, because the requirements of 40 CFR 403.8(f)(2) apply to 
POTWs with approved Pretreatment programs rather than Control 
Authorities in general, the discussion here distinguishes between the 
authority granted to Control Authorities in 40 CFR 403.12(e) to waive 
monitoring for pollutants not present, and the reduction in monitoring 
requirements for POTWs for these pollutants in 40 CFR 403.8(f)(2)(v).
1. What Were the Rules in Place Prior to Today's Rulemaking?
    Section 403.12(e)(1) required Industrial Users subject to 
categorical Pretreatment Standards to submit reports to the Control 
Authority at least twice each year indicating the nature and 
concentration of all pollutants in their effluent that are limited by 
an applicable Standard. Prior to today's rulemaking, the Control 
Authority was not authorized to reduce monitoring of pollutants 
regulated by the applicable categorical Pretreatment Standard to less 
than twice per year. 40 CFR 403.8(f)(2)(v) also required POTWs to 
sample these Industrial Users at least annually to independently verify 
compliance with the Standard. Semiannual sampling by the Industrial 
User and annual sampling by the POTW was required for all pollutants 
limited by the categorical Pretreatment Standard even if certain 
pollutants regulated by the Standard were not reasonably expected to be 
present.
2. What changes did EPA propose?
    The proposal would amend the current regulation to authorize the 
Control Authority to waive the sampling requirements for an Industrial 
User subject to a categorical Pretreatment Standard for a pollutant if 
the pollutant was not expected to be present in the wastestream in a 
quantity greater than the background level present in its water supply, 
with no increase in the pollutant in the wastewater attributable to the 
industrial process. In lieu of monitoring for the pollutants determined 
not present, the Industrial User would submit a certification as part 
of its semiannual monitoring reports that there had been no increase in 
the pollutant in its wastewater due to its activities. This change 
would also reduce a POTW's sampling requirement once it had determined 
that a pollutant was not expected to be present. However, as proposed, 
the reduced sampling would not have been available to facilities 
subject to the Organic Chemicals, Plastics, and Synthetic Fibers 
(OCPSF) guidelines, 40 CFR part 414.
3. What changes is EPA finalizing in today's rule?
    Today, EPA is adopting the proposed changes which authorize a 
Control Authority to waive the monitoring requirements in semiannual 
reports required under 40 CFR 403.12(e) for individual pollutants, 
including indicator or surrogate pollutants, for an Industrial User 
subject to a categorical Pretreatment Standard. A Control Authority may 
waive this requirement if it determines that the pollutant is neither 
present nor expected to be present, at levels greater than that of the 
intake water, without any increase in the pollutant due to the 
activities of the Industrial User. The waiver will not be available for 
monitoring required for the baseline monitoring report required under 
40 CFR 403.12(b) or the 90-day compliance report required under 40 CFR 
403.12(d). The Industrial User must continue to conduct at least twice-
per-year monitoring until the waiver is both granted by the Control 
Authority and incorporated into the Industrial User's control 
mechanism. The POTW's annual monitoring requirements for the pollutant 
for which a monitoring waiver is granted may be reduced to a minimum of 
once during the effective period of the Industrial User's control 
mechanism.
    In finalizing the rule, EPA is making the following changes to the 
proposed rule:
    Coverage for OCPSF Facilities: EPA has determined that it is 
appropriate for the monitoring waiver to be available to Industrial 
Users subject to the OCPSF guidelines and is not limiting the 
availability in any way different from other Categorical Industrial 
Users.

[[Page 60139]]

    Industrial User Sampling Data: The final rule requires that to 
demonstrate that the pollutant is not present, the Industrial User must 
provide the results of one or more samples prior to treatment which are 
representative of all process wastewater.
    Notice to Control Authority if Pollutant Found to be Present: The 
final rule includes a provision which requires that in the event that a 
pollutant is subsequently found to be present or is expected to be 
present, the Industrial User must immediately resume monitoring and 
notify the Control Authority.
    Control Mechanism Issues: EPA clarifies that the Control Authority 
must include any waiver granted to an Industrial User in the User's 
control mechanism. The Control Authority must also document the reasons 
for authorizing the waiver and maintain any information submitted by 
the User in support of the waiver for at least three years after 
expiration of the waiver. The waiver is valid only for the duration of 
the control mechanism. In order to continue the waiver for the period 
of the next control mechanism, the Industrial User will need to reapply 
for the waiver, including the submission of appropriate monitoring 
data. The control mechanism must include the requirement for the 
Industrial User to immediately notify the Control Authority in the 
event that the pollutant is found or suspected to be present, and to 
resume monitoring at least semiannually. The control mechanism still 
must include all applicable categorical Standards, even those Standards 
for which monitoring has been waived.
    Waiver Does Not Supercede Other Certifications: EPA has included a 
provision which states that the waiver of monitoring requirements 
cannot replace any certification requirements that have been 
established in specific categorical Pretreatment Standards.
4. Summary of Major Comments and EPA Response
    How does EPA define ``not present?'' In the preamble to the 
proposed amendments, EPA specifically requested comment on how to 
define what is meant by ``not present.'' Several commenters suggested 
that a precise definition was not necessary based on the regulatory 
context. Other commenters suggested that it be defined in terms of a 
percentage of the applicable limit, while others suggested that the 
term be defined as at or below the levels found in the water supply. 
The final regulatory language clearly indicates that monitoring for a 
pollutant can be waived as long as the levels in the untreated 
wastewater do not exceed the levels in the intake water based on 
``sampling and other technical factors.'' EPA did not promulgate a 
definition of not present when the similar NPDES revision was 
finalized, and EPA continues to view the final regulatory language as 
sufficiently clear to avoid confusion.
    In response to commenters that suggested that ``not present'' be 
defined as a percentage of the applicable categorical Standard, EPA 
notes that today's waiver is not for pollutants that are not reasonably 
expected to violate the Standard, but rather for pollutants that are 
neither present nor expected to be present in the Discharge above 
background levels. Therefore, the level of pollutant in the Discharge 
in relation to the Standard is not the relevant benchmark for the 
Control Authority's determination whether the waiver request should be 
granted. Instead, what matters in the determination is whether the 
Industrial User's practices or industrial processes add the pollutant. 
The Control Authority already has the ability to reduce monitoring to 
as infrequently as twice per year for any pollutants that are in the 
Discharge but are not reasonably expected to violate the Standard. 
However, if the background level from the Industrial User's intake 
water already exceeds the applicable categorical Standard, a waiver of 
the monitoring requirements would not be available unless the Control 
Authority has adjusted the categorical Standard using the net/gross 
provision of 40 CFR 403.15, and the pollutant is not added to the 
wastewater by the discharger's practices or processes.
    Several commenters also suggested that if a pollutant is added in 
``negligible'' amounts or in amounts equal to ``typical'' domestic 
levels, the Control Authority should still be authorized to grant the 
monitoring waiver. EPA addressed this issue in the preamble to the 
final NPDES regulation dealing with a waiver of monitoring requirements 
for direct dischargers. There, EPA stated:

    ``EPA declines to allow monitoring waivers for pollutants that 
are added by dischargers in minute amounts (e.g., use of common 
cleaners or from research operations) because human activity might 
lead to substantial increases in those pollutant Discharges which 
may threaten the aquatic environment. Consequently, there is a 
continuing need to monitor those pollutants. EPA also notes that at 
least one national effluent guideline addresses the introduction of 
incidental amounts of pollutants from cleaning, maintenance, or 
research operations and EPA does not believe it is appropriate to 
apply the waiver to a pollutant that is added to the wastestream and 
subject to an effluent guideline. See 40 CFR 414.11(b) (applying the 
Organic Chemicals, Plastics, and Synthetic Fibers Effluent 
Guidelines to wastewater Discharges from research and development 
operations). Metals or other pollutants that can leach from pipes 
may also pose a threat to the environment and EPA believes 
monitoring should be retained for such Discharges. With respect to 
pollutants which occur in amounts below ``levels of concern'', the 
discharge of such pollutants can also increase from human activity 
and EPA believes that monitoring is necessary to ensure that an 
appropriate level of treatment continues to be provided.'' (65 FR 
30892, May 15, 2000).

Nothing submitted by commenters has changed the Agency's mind in the 
case of indirect dischargers with respect to its earlier conclusion.
    Some commenters also suggested that EPA clarify that the term 
``quantities'' as used in the proposal may mean mass loading in 
addition to concentration. EPA agrees that there may be instances where 
the use of mass may be more appropriate than concentration, and 
therefore will allow Control Authorities to use pollutant mass to 
compare the levels of pollutants in the wastewater to the levels of 
pollutants in the intake water. If the Industrial User can demonstrate 
through its technical evaluation that a specific pollutant is not 
added, and can demonstrate through a mass balance that any increases in 
the wastestream concentration are due only to evaporative losses or 
other similar reductions in the volume of wastewater discharged, then a 
monitoring waiver may be approved by the Control Authority. Note that 
accurate flow measurements will be necessary to perform the appropriate 
mass-balance calculations and demonstrate that small amounts of the 
pollutant are not added in the course of the facility activity. One 
example submitted by a commenter notes that cooling tower maintenance 
chemicals may add the pollutant of concern to the wastestream. If the 
pollutant of concern is added by the User in any way to the 
wastestream, then the Industrial User would not be eligible for the 
waiver. To the extent that the concentration is increased significantly 
such that it may impact the POTW, EPA would expect that a monitoring 
waiver would not be granted. In response to this comment, EPA is 
revising the language in the final regulation to refer to the 
``levels'' of pollutants in the intake water rather than the 
``concentration'' of pollutants in the intake water. This wording 
change is consistent with the similar NPDES permitting requirement for

[[Page 60140]]

direct dischargers (see 40 CFR 122.44(a)(2)(i)).
    One commenter noted that EPA's use of the phrase ``with no increase 
in the pollutant due to the regulated process'' could create confusion 
in how to handle pollutants that are added in other facility 
wastestreams that are not regulated by the applicable categorical 
Pretreatment Standard. EPA agrees that the phrase ``with no increase in 
the pollutant due to the regulated process'' is not appropriate. 
Although the phrase was used in the preamble to the proposal and not 
the proposed regulation, EPA is revising the final regulatory language 
to include the phrase ``without any increase in the pollutant due to 
the activities of the Industrial User''. This phrase better reflects 
EPA's intent that the waiver would not be available for a pollutant 
where the Industrial User may add the pollutant through means other 
than the regulated industrial process (except for sanitary wastewater--
see below).
    Should Industrial Users have the authority to waive sampling 
requirements rather than the Control Authority? Several commenters 
suggested that it would be appropriate for the Industrial User to have 
the authority to make the determination on whether a pollutant is 
present and monitoring requirements should be waived rather than the 
Control Authority. EPA disagrees that Industrial Users rather than the 
Control Authority should have the authority to waive monitoring for 
pollutants not present. The Control Authority is the regulatory agency 
responsible for ensuring compliance with applicable Standards, and is 
therefore the most appropriate agency for determining the monitoring 
requirements necessary for it to fulfill that responsibility. In 
addition, placing the authority with the Industrial User eliminates 
oversight that, in EPA's view, is necessary to ensure that this 
provision is implemented correctly.
    What information is necessary to determine if a pollutant is not 
present at a facility? EPA received many comments suggesting what type 
of data is needed in order to make an informed decision on whether a 
pollutant is neither present nor expected to be present. Commenters 
noted that information contained in control mechanism applications and 
baseline monitoring reports, as well as data obtained through a 
thorough facility inspection could all be used to support a 
determination that a pollutant is not present. The commenters noted 
that these are all mechanisms for obtaining data on the raw materials, 
products, and by-products used and generated at an Industrial User. EPA 
agrees that these are valid sources of information that can contribute 
to an Industrial User's demonstration that a pollutant is neither 
present nor expected to be present. EPA notes that the Industrial User 
monitoring waiver in today's rule applies to the semiannual monitoring 
required under 40 CFR 403.12(e), and does not apply to monitoring 
required for the baseline monitoring report or the 90-day compliance 
report. EPA has also concluded that if the Control Authority uses a 
control mechanism application form, such a form is an appropriate place 
for the Industrial User to request the monitoring waiver, although the 
mechanism for how the request is made is largely up to the discretion 
of the Control Authority.
    Commenters also suggested that material safety data sheets would be 
a valuable tool in determining whether specific pollutants are present 
in the raw materials or other chemicals used at the facility. EPA notes 
that material safety data sheets do not identify all of the pollutants 
present in a given material, and therefore cannot be relied upon to 
determine whether a pollutant is present in the raw materials or other 
chemicals at the Industrial User's facility. In order for the Control 
Authority to accurately determine the presence of a pollutant in a 
given raw material or other chemical, the Industrial User will need to 
analyze the material in question, or obtain a certificate of analysis 
from the manufacturer of the material demonstrating the absence of the 
pollutant. In addition, the evaluation needs to include materials not 
necessarily used for the product, such as chemicals used in equipment 
cleaning and wastewater treatment. Although wastewater treatment 
chemicals are used to reduce the levels of pollutants in the Discharge, 
analysis of the chemicals can show significant levels of contaminants 
that can be added to the wastewater stream. Additional information, 
such as intermediate products, final products, and byproducts generated 
in the process will need to be considered as well, and therefore a 
detailed knowledge and evaluation of the process chemistry involved in 
the manufacturing operations will be necessary.
    Some commenters suggested that the determination of whether a 
pollutant is present should be based exclusively on a review of 
available information. While available information should certainly be 
used in the determination, and EPA would expect that most Industrial 
Users requesting the waiver would have a fairly extensive knowledge of 
the pollutants present in their wastewater, because the pollutants are 
either directly added or generated as byproducts, an Industrial User 
cannot assume that a pollutant is not present in its Discharge simply 
because it has not generated any information to suggest otherwise. EPA 
notes that the Industrial User has the burden to demonstrate that the 
pollutant is not present, and if this demonstration cannot be made to 
the satisfaction of the Control Authority, the waiver may not be 
granted.
    EPA does agree that the determination of whether a pollutant is 
present should be based on whether or not that pollutant would have the 
potential to enter the wastestream to the POTW. Such an evaluation must 
include the potential for the pollutants to enter the wastestream 
through spills and other potentially infrequent events, in addition to 
whether the pollutant would be routinely expected to enter the 
wastestream. Therefore, in order for monitoring for the pollutant to be 
waived, there must be a high degree of certainty that the pollutant 
will not show up in the Discharge to the POTW.
    EPA also notes that for facilities that use the combined 
wastestream formula, ``unregulated'' wastestreams may be covered by the 
categorical Standard through the adjusted Standard. Therefore, EPA has 
concluded that it is not appropriate to allow a monitoring waiver where 
wastestreams other than those regulated by the categorical Standard 
contribute the pollutant of concern. However, since pollutants, 
especially metals, may be present in sanitary wastestreams at higher 
than background concentrations, and because sanitary wastestreams are 
not typically regulated through categorical Standards specifically or 
the Pretreatment program in general, the revised regulation provides 
that waivers may be granted where the only source of the increase in 
the pollutant from human activity is sanitary wastewater, provided that 
the sanitary wastewater is not regulated by an applicable categorical 
Standard and does not include the pollutant at levels that are 
significantly higher than typical domestic levels for the POTW's 
service area. See 40 CFR 403.12 (e)(2)(i).
    One commenter noted several industries that claimed that a 
pollutant was not present in their Discharge, only to have it show up 
in monitoring results. EPA is aware of similar instances and knows of 
circumstances where the pollutants are later detected in the sampling 
data at fairly high levels. This is one of the reasons why EPA is 
requiring that the technical evaluation of the facility to determine 
the presence of the pollutant be

[[Page 60141]]

supported by sampling data, including data prior to treatment. Even 
though EPA is generally not requiring a minimum amount of data (with 
the exception of the one sample required prior to treatment), Control 
Authorities are expected to have sufficient sampling data to support 
the technical evaluation. Where monitoring data shows that the 
pollutant is present at levels above the background intake water level, 
the Control Authority must deny the request for the monitoring waiver.
    How much sampling data is necessary to make a determination that a 
pollutant is not present? Comments on this issue varied from suggesting 
that no sampling is necessary to providing suggestions on specific 
sampling frequencies for the intake water as well as the effluent 
Discharge. One commenter suggested that no influent monitoring data was 
necessary if the effluent data shows no detectable levels of the 
pollutant. Although EPA has concluded that some sampling data is 
necessary to document the absence of a pollutant in the Discharge, the 
amount of sampling necessary for the determination is most 
appropriately determined on a site-specific basis, and will depend, in 
part, on how convincing are the arguments regarding the ``other 
technical factors''. Therefore, EPA is not establishing a minimum 
monitoring frequency. This is also consistent with the NPDES 
regulations, which do not establish a minimum sampling frequency. EPA 
is, however, establishing a minimum requirement that one sample be 
collected prior to treatment. Data prior to treatment is necessary to 
demonstrate that the measured levels reflect any pollutants that are 
added to the wastewater rather than the levels after they have been 
reduced by treatment, since effective treatment could become less 
effective over time. Other data that may be used in the evaluation 
include final effluent data and in many cases the facility intake 
water.
    It is important to note that the pollutant monitoring waiver is 
based on a facility-wide evaluation and, therefore, sampling data must 
be representative of all wastestreams, as well as any seasonal or other 
variability in the Discharge. In addition, note that the monitoring 
waiver is for pollutants that are neither present nor expected to be 
present, and not for pollutants which are added but for which no 
violation of the applicable Standard is expected. In some cases, the 
existing monitoring data will be sufficient to evaluate the presence of 
the pollutant in the Discharge. The data prior to treatment is less 
likely to have been collected in the past, although historic data, if 
still representative, can be used.
    EPA has concluded that a sequential approach to sampling is the 
most appropriate way to evaluate the request for a monitoring waiver 
based on sampling data. If monitoring of the Industrial User's 
wastewater prior to treatment (and after treatment where appropriate) 
shows no detectable levels of the pollutant based on the most sensitive 
EPA approved method, then no sampling of the intake water is necessary 
because the levels of the pollutant in the Discharge will already have 
been shown to be at or below the levels in the intake water. However, 
if a pollutant is present in the Industrial User's wastewater, data on 
the levels in the influent water are necessary to determine whether the 
presence of the pollutant is solely the result of levels in the 
influent water, or the result of the Industrial User adding the 
pollutant to some extent. Background levels of pollutants in an 
Industrial User's influent water will vary from POTW to POTW, and 
possibly from Industrial User to Industrial User based on many factors. 
If historical data is available, based on prior sampling by either the 
Industrial User or the POTW, or based on drinking water system data 
that is representative of the Industrial User's intake water, 
additional sampling may not be necessary.
    EPA notes that data for intake water must be representative of the 
water typically used at the facility, but prior to any water treatment 
or conditioning provided by the Industrial User. This generally means 
that the data, especially for lead and copper, should reflect pollutant 
levels of intake water that have been running continuously for at least 
several minutes, rather than pollutant levels of intake water that have 
been sitting in the pipes for several hours. Water system data for lead 
and copper will typically reflect the levels of pollutants in the water 
after it has been sitting in the pipes for at least six hours. Because 
this data is not generally representative of the levels of lead and 
copper in the typical facility intake water, drinking water data for 
lead and copper may not be representative of the Industrial User's 
actual intake water and should not be used unless the Industrial User 
can demonstrate to the satisfaction of the Control Authority that the 
lead and copper levels are actually representative.
    How should Control Authorities and Industrial Users address 
analytical variability when determining if a pollutant is present above 
background levels? One commenter requested clarification on how to 
handle a situation where the Industrial User and the Control Authority 
had determined that a pollutant was not present, but subsequently found 
slightly higher levels based on monitoring data. EPA acknowledges that 
there is some variability in sample results. Therefore, it is possible 
that slightly higher levels of pollutants may be measured in the 
Industrial User's wastewater than in the intake water. If the higher 
levels are within the method variability and the technical evaluation 
shows that the pollutant is neither present nor expected to be present, 
then the results should be considered equal. If the higher levels are 
above the method variability, then the pollutant should be considered 
to be present unless the Industrial User can demonstrate that the 
sample result was in error, or that the intake levels of the pollutant 
have risen to the same extent. EPA notes that the burden is on the 
Industrial User to demonstrate that an analytical error has occurred 
through re-analysis of the sample or other similar means. An unexpected 
result is not sufficient justification to consider a sample result to 
be in error since, as noted above, sampling data at times finds 
pollutants which were not expected to be present. Likewise, the 
Industrial User would need to provide sampling data demonstrating that 
the levels of the pollutant in question have risen in the intake water 
if it believes that this is the reason for the higher levels of the 
pollutant in its wastewater.
    Should any ongoing POTW monitoring be required to demonstrate that 
the waived pollutant continues to be absent from the Discharge? Not all 
commenters agreed with the EPA proposal requiring POTW's to monitor for 
any waived pollutants at least once during the effective period of the 
Industrial User's control mechanism. These commenters believed that the 
combination of the certification and the requirement to report changes 
in the Discharge were sufficient to ensure that the Control Authority 
would become aware of changes that would require a resumption of 
monitoring. Other commenters believed that the once per control 
mechanism term was appropriate and would not burden POTWs, while other 
commenters believed that monitoring once per year for the waived 
pollutants was appropriate. EPA disagrees that annual monitoring will 
be necessary to determine whether or not the pollutant is present. As 
stated in the preamble of the proposal, EPA asserts that if the Control 
Authority has determined, based on both sampling data and a

[[Page 60142]]

technical evaluation, that a pollutant is not present at levels above 
background, and if the Industrial User continues to certify that there 
is no increase in the pollutant in its wastewater due to the activities 
of the Industrial User, then it is appropriate to allow the Control 
Authority to determine whether to sample the facility more frequently 
than once during the term of the control mechanism. EPA received no 
data to suggest that more frequent monitoring is necessary. EPA notes 
that the Control Authority has the discretion to determine that the 
Industrial User must monitor for a pollutant despite the User having 
demonstrated that it is not present. Where the Control Authority elects 
to require monitoring in such circumstances, it may determine the 
appropriate frequency of monitoring, including frequencies that are 
less than twice per year. In addition, the Industrial User may also 
monitor on its own, even though the requirement to do so has been 
waived, but in this case the Industrial User must report the results of 
that monitoring to the Control Authority in accordance with 40 CFR 
403.12(g)(6).
    Although EPA is not requiring annual monitoring by the POTW, EPA 
has concluded that at least one effluent sample during the term of the 
Industrial User's control mechanism is necessary to confirm that no 
changes have occurred, and that the monitoring waiver is still 
appropriate. EPA is requiring that this monitoring be done by the POTW 
to ensure an independent assessment of the Industrial User. EPA has 
concluded that the most appropriate time for the monitoring to occur is 
during the renewal of the control mechanism. However, EPA also asserts 
that the timing is best left to the discretion of the POTW and, 
therefore, is not requiring that the monitoring occur at any specific 
time during the duration of the control mechanism.
    Should the waiver be available for pollutants that in the past have 
caused Pass Through or Interference, or otherwise caused problems at 
the POTW? One commenter suggested that the monitoring waiver for 
pollutants not present should not be available for pollutants which 
have been problematic for the POTW in the past. EPA agrees that POTWs 
must be more careful when waiving the monitoring requirements for 
pollutants for which the POTW has previously experienced problems. In 
these instances, more monitoring data and a more careful review of the 
technical evaluation is warranted. However, if the pollutant is truly 
not present at the facility or in the Discharge and there is no 
potential for spills or slug loads of the pollutant, EPA does not view 
it as necessary to require monitoring at that Industrial User's 
facility merely because the pollutant was associated with past POTW 
problems and, therefore, will not prohibit granting a waiver in these 
circumstances. Granting the waiver is at the discretion of the Control 
Authority, and where there has been a history of problems with a 
pollutant at the POTW, the Control Authority may deny a waiver, if it 
deems this necessary to prevent future problems.
    Is the waiver available for facilities subject to the Organic 
Chemicals, Plastics, and Synthetic Fibers category? Most comments 
supported allowing waiver of the monitoring requirements for pollutants 
not present for facilities subject to the OCPSF Standards. EPA agrees 
that Control Authorities should be able to grant the monitoring waiver 
to OCPSF dischargers if appropriate. Several commenters indicated that 
they know of OCPSF facilities that manufacture a limited number of 
products and have fairly consistent Discharges. A monitoring waiver for 
some regulated pollutants may be appropriate for such facilities and, 
therefore, a blanket exclusion for all OCPSF facilities from the waiver 
would not be appropriate. However, EPA notes that production and 
Discharges from OCPSF facilities can be highly variable. Control 
Authorities must ensure that sufficient information, including sampling 
data, is available to assess whether a particular pollutant is present 
at any time, taking into consideration all of the variability in 
production. When a particular pollutant may be present at some time 
based on the products that are manufactured at the facility, even if 
the pollutant is not currently present, a monitoring waiver for that 
pollutant would not be appropriate. If any facility's operations, 
regardless of whether they are subject to OCPSF Standards or not, are 
sufficiently variable that a reasonable determination cannot be made as 
to whether a pollutant will consistently be absent from the Discharge, 
the Control Authority may not grant a waiver.
    How does the waiver for pollutants neither present nor expected to 
be present affect other waivers specifically included in a categorical 
Pretreatment Standard, such as the option under the metal finishing 
Standards allowing for implementation of a toxic organics management 
plan in lieu of monitoring for total toxic organics? Several commenters 
compared the waiver of monitoring for pollutants not present being 
promulgated today to other monitoring waivers such as the management 
plan and certification option under the metal finishing Standards in 
lieu of total toxic organics monitoring. In order to avoid any 
potential confusion, EPA is adding specific language to today's 
regulations which states that the monitoring waiver and certification 
for a pollutant that is not present cannot be used in place of any 
certification process established in categorical Pretreatment 
Standards. Therefore, today's monitoring waiver would not be available, 
for example, for total toxic organics under the metal finishing 
regulations. Rather, in order to reduce its monitoring for total toxic 
organics, a metal finisher would need to use the management plan and 
certification process contained in 40 CFR 433.12. Since the metal 
finishing and other category-specific certifications were established 
for an identified set of facilities based on an evaluation of those 
facilities, while today's monitoring waiver is being established 
generally without a reevaluation of each categorical Pretreatment 
Standard, EPA has concluded that it is not appropriate for today's 
waiver to supercede these more specific certifications. EPA notes that 
the equivalent NPDES Permit requirement includes this same provision. 
See 40 CFR 122.44(a)(2)(v). However, while the general waiver for 
pollutants neither present nor expected to be present cannot substitute 
for a category-specific certification requirement, the data and 
analyses that would otherwise be used to support such a waiver may be 
relevant to, and if so form part of the basis for, the category-
specific certification.
    While today's rule provides that the monitoring waiver and 
certification for a pollutant that is not present cannot be used in 
place of any certification process already established in existing 
categorical Pretreatment Standards, the monitoring waiver is available 
for pollutants that are analyzed as surrogates for other pollutants.
    What happens if a facility's operations change so that a pollutant 
for which a monitoring waiver has been granted is now present at the 
facility? Several commenters correctly noted that 40 CFR 403.12(j) 
requires that Industrial Users provide notification of any substantial 
changes in the volume or character of pollutants in the Discharge. This 
notification requirement would apply in the event that a pollutant for 
which monitoring was waived became present at the Industrial User for 
any reason. However, the language in 40 CFR 403.12(j) refers to 
pollutants in the Industrial User's Discharge rather than any pollutant 
at the facility which is or may be added to the wastestream.

[[Page 60143]]

Therefore, in order to clarify the requirement for waived pollutants, 
EPA has added language to the final regulation that states that 
notification is necessary, and that the Industrial User must 
immediately resume monitoring, if the pollutant is found or suspected 
to be present. The requirement to resume monitoring would apply even 
before the Industrial User's control mechanism is revised to reflect 
the resumed monitoring. Control mechanisms that include the monitoring 
waiver must also include language requiring notification and the 
resumption of monitoring in the event that a pollutant is subsequently 
determined to be present at the facility. Failure to provide the 
required notification or to resume monitoring is a violation of the 
Industrial User's control mechanism and the General Pretreatment 
Regulations. EPA also recommends that any control mechanism issued 
incorporating a monitoring waiver includes a reopener clause which 
allows the Control Authority to revise or revoke the waiver if 
appropriate.
    Where a facility has been granted a waiver of monitoring for a 
pollutant that has been determined not to be present and it installs or 
constructs new production lines or processes, the Industrial User must 
evaluate the new production lines or processes and determine whether 
they may cause the pollutant to be present, in which case the facility 
must resume monitoring.
    How often will certification that the pollutant is not present in 
the Discharge be required? EPA proposed that certification that a 
pollutant is not present at the facility be submitted twice-per-year 
with the semiannual reports otherwise required under 40 CFR 403.12(e). 
Several commenters supported this approach, while others believed that 
a once-per-year certification would be sufficient, or that no 
certification should be required, especially since the Industrial User 
is required to report changes at the facility to the POTW. EPA has 
concluded that twice-per-year certification will not impose a 
significantly greater burden on Industrial Users than once-per-year 
certification since in most cases the reports would still be submitted 
at least twice-per-year even if monitoring for some pollutants is 
waived. In addition, it often may be easier for the Industrial User to 
include the certification with every report rather than determining 
which reports need the certification and which do not. Although 
required to report changes in the facility, an Industrial User's 
willingness to certify that the pollutant is not present in the 
Discharge provides an additional assurance that the pollutant is not 
present above background levels. Accordingly, EPA has decided to 
maintain the twice-per-year certification requirement.
    In addition, EPA has clarified the language of the certification 
requirement to state that once an Industrial User has received a 
monitoring waiver, the certification is required and is not optional. 
If the Industrial User is no longer certain that the pollutant is not 
present, it must notify the Control Authority and immediately begin 
monitoring. EPA intends that the monitoring waiver be used in instances 
where a pollutant is consistently not present at a facility, and is not 
to be used for short periods of time when the pollutant is not present.
    It should be noted that the certification provided in the 40 CFR 
403.12(e)(2)(v) includes two blank spaces which are to be filled in by 
the Industrial User. In the first blank space, the Industrial User is 
to specify the applicable Pretreatment Standard(s) that apply to the 
facility (e.g., 40 CFR 433.15). In the second blank space, the 
Industrial User is to list the pollutants for which the monitoring 
waiver has been granted. As noted above, the certification must include 
all of the pollutants for which a monitoring waiver has been granted. 
The Control Authority may also fill in the blank spaces before 
incorporating the certification language into the Industrial User's 
control mechanism for use by the Industrial User with the semiannual or 
more frequent reports.
    Should the waiver be available for new Industrial Users, or during 
an Industrial User's first control mechanism? EPA noted in the preamble 
to the proposed rule that the equivalent NPDES provision did not allow 
the monitoring waiver to be granted to New Sources/New Dischargers for 
the term of their first NPDES Permit. Comments on this issue were 
divided, with some commenters noting that the term of the first control 
mechanism is a good time to collect data on the presence of the 
pollutant at the facility, while other commenters believed that the 
Control Authority would generally be able to determine the presence of 
the pollutant, even for the first control mechanism. It is EPA's view 
that the Control Authority may need time to collect enough data to 
appropriately assess whether pollutants at a new Industrial User are 
consistently not present and, therefore, should be cautious in 
approving a waiver for new Industrial Users. Time may be necessary to 
determine whether there are seasonal or other variations in the 
operations that would result in the pollutants being present 
periodically. However, the length of time needed to collect the data 
and make the assessment will vary depending on site-specific factors. 
Therefore, EPA has not included language in the regulation restricting 
the eligibility of a new Industrial User for a monitoring waiver for 
pollutants that are not present.
    What documentation of the waiver is required? Several commenters 
noted the need to document the waiver when it is approved by the 
Control Authority. EPA agrees that this documentation is important for 
the Approval Authority and the general public to ensure that waivers 
are properly granted. Pursuant to 40 CFR 403.14, this information must 
be made publicly available. It has always been EPA's intent that any 
monitoring waivers would be documented in the Industrial User's control 
mechanism. Today's regulation also specifically requires that the 
Control Authority's rationale for granting the waiver and any 
information submitted by the Industrial User in its request for a 
monitoring waiver be maintained by the Control Authority for at least 
three years after the expiration of the waiver.

B. General Control Mechanisms (40 CFR 403.8(f)(1)(iii))

    Today's final rule clarifies that POTWs may use general control 
mechanisms, such as general permits, to regulate the activities of 
groups of Significant Industrial Users (SIUs). Provided that the 
necessary legal authority exists, the POTW may use a general control 
mechanism for any facilities that meet certain minimum criteria for 
being considered substantially similar.
    In the NPDES permitting context, the use of general permits (see 40 
CFR 122.28) allows the permitting authority to allocate resources in a 
more efficient manner and to provide timelier permit coverage. For 
example, direct dischargers with common characteristics may be covered 
under a general permit without the permitting authority expending time 
and money to issue individual permits to each of these facilities. The 
use of a general permit also ensures consistency of permit conditions 
for similar facilities. In the Pretreatment context, POTWs might 
benefit from the use of control mechanisms for Discharges from SIUs to 
POTWs which are similar to the general permits used in the NPDES 
program.
    This modification should help POTWs by providing a cost-effective 
method to cover large numbers of similar facilities under a single 
mechanism. This is expected to reduce

[[Page 60144]]

the administrative burden of issuing separate mechanisms to similar 
facilities.
1. What were the rules in place prior to today's rulemaking?
    Prior to today's rulemaking, the Pretreatment Regulations allowed 
POTWs to use general control mechanisms to control non-Significant 
Industrial Users, but required individual control mechanisms for SIUs. 
Section 403.8(f)(1)(iii) required POTWs to ``Control through, order, or 
similar means, the contribution to the POTW by each Industrial User to 
ensure compliance. * * * In the case of Industrial Users identified as 
significant * * *, this control shall be achieved through s or 
equivalent individual control mechanisms issued to each such User.'' 
The preamble to the regulation which originally required control 
mechanisms for SIUs emphasized the importance of POTWs evaluating SIUs 
on an individual basis to determine the need for individual 
requirements as necessary. See 55 FR 30082 (July 24, 1990).
2. What changes did EPA propose?
    EPA proposed to revise the regulation by authorizing POTWs to use 
``general permits'' to regulate SIUs in certain circumstances. Under 
the proposal, all of the facilities to be covered by a general permit 
must employ the same or substantially similar types of industrial 
processes; discharge the same types of wastes; require the same 
effluent limitations; and require the same or similar monitoring. These 
requirements reflect the existing criteria for using general permits 
for direct dischargers at 40 CFR 122.28(a)(2)(i). EPA also indicated 
that the use of a general permit does not relieve the SIU from any 
reporting or compliance obligations under Part 403.
3. What changes is EPA finalizing in today's rule?
    In today's rule, EPA is finalizing the proposed rule's change to 
allow the use of general control mechanisms for SIUs. Section 
403.8(f)(1)(iii) contains the revisions which authorize general control 
mechanisms.
    EPA notes that today's rule replaces the term ``general permit'' 
with ``general control mechanism''. This terminology is more consistent 
with the existing Pretreatment Regulations which require that SIUs be 
controlled through ``permits or equivalent individual control 
mechanisms.'' Just as EPA has not precluded the use of an ``order or 
similar means'' to regulate individual SIUs, it also is not ruling out 
the use of other mechanisms besides permits to address groupings of 
SIUs. This decision is based on the rationale EPA provided when the 
Agency first promulgated the requirement that POTWs regulate SIUs 
through individual control mechanisms to SIUs. See 55 FR 30107, July 
24, 1990. EPA is including the relevant passage from this final rule 
for reference:

    ``* * * the Agency will require issuance of ``individual 
Discharge permits or equivalent control mechanisms.'' An adequate 
equivalent control mechanism is one which ensures the same degree of 
specificity and control as a permit. To clarify that the conditions 
of the individual control mechanism must be enforceable against the 
Significant Industrial User through the usual remedies for 
noncompliance (set forth in 40 CFR 403.8(f)(1)(vi)(A), EPA has 
amended the language of 40 CFR 403.8(f)(1)(vi)(B) to provide that 
Pretreatment requirements enforced through the remedies of 40 CFR 
403.8(f)(1)(vi)(A) shall include the requirements set forth in 
individual control mechanisms. In addition, the Agency has added to 
proposed 40 CFR 403.8(f)(1)(iii) a statement that individual control 
mechanisms must be enforceable.

    What types of facilities may be subject to a general control 
mechanism? SIUs that are covered by concentration-based Standards and 
Best Management Practices may be subject to general control mechanisms. 
However, due to the requirement that all facilities covered under the 
same mechanism ``require the same effluent limitations'', facilities 
regulated by categorical Standards expressed as mass limits, which are 
inherently unique to each individual User, can not receive coverage 
under a general control mechanism. The one exception to this exclusion 
would be situations where the POTW has imposed the same mass-based 
local limit on a number of facilities, and any categorical Standards 
are expressed as concentration limits or BMPs. In addition, general 
control mechanisms are not available for Industrial Users whose limits 
are based on the Combined Wastestream Formula or Net/Gross 
calculations, or other calculated categorical Pretreatment Standard 
equivalents (40 CFR 403.6(e) and 40 CFR 403.15).
    How does an SIU apply for coverage under a general control 
mechanism? For an individual SIU to be covered by a general control 
mechanism, it must file a ``written request for coverage'' with the 
POTW. Through the request for coverage, the Industrial User should 
identify its production processes, the types of waste generated, and 
the monitoring location or locations at which all regulated wastewaters 
will be monitored. The request for coverage should also include a 
finding that the SIU properly falls within the category of facilities 
covered by the general control mechanism. In addition, the SIU's 
request for coverage should include an indication of whether the User 
is requesting a monitoring waiver for pollutants not present.
    The POTW does not necessarily need to establish an entirely new 
application process for SIUs seeking coverage under a general control 
mechanism. Existing procedures or forms may be used to provide 
coverage. The POTW may find that it is necessary to supplement existing 
procedures or forms to add the information EPA recommends for inclusion 
in the requests for coverage, as discussed in the preceding paragraph.
    How does the POTW adopt general control mechanisms? A POTW must 
have the necessary legal authority if it wants to issue general control 
mechanisms. Legal authority changes would include the adoption of 
ordinance language consistent with today's changes to 40 CFR 
403.8(f)(1)(iii) and the development of any policies or procedures that 
would support the issuance and implementation of general control 
mechanisms. Refer to Section VI for a more detailed discussion of 
Program modifications.
    In addition, general control mechanisms have to be enforceable to 
the same extent as an individual control mechanism. The POTW should 
also have enforcement authority to take action against Industrial Users 
that fail to file the required request for a general control mechanism, 
i.e., an IU that fails to file is subject to enforcement for 
discharging without authorization.
    The POTW should develop the general control mechanism and provide 
notice that it is available. The general control mechanism should, of 
course, specify exactly what characteristics or conditions make an 
Industrial User eligible for coverage. The general control mechanism 
must also impose all of the conditions of individual control mechanisms 
listed in 40 CFR 403.8(f)(1)(iii)(B)(1)-(6).
    A POTW may make coverage by the general control mechanism mandatory 
or optional. In either case, if an Industrial User is to be covered by 
the general control mechanism, it must file the written request for 
coverage to be covered by the general control mechanism. The POTW 
should consider how it will notify SIUs, subsequent to their filing a 
written request for coverage, that they are authorized to discharge 
under the general control mechanism, including how it will memorialize 
certain facility-specific factors such as sampling location. EPA

[[Page 60145]]

notes that the POTW's annual report should indicate which SIUs are 
covered by each general permit.
    Today's final rule does not preclude POTWs from requiring 
individual control mechanisms for specific Industrial Users, even if 
they might otherwise satisfy the conditions for a general control 
mechanism, where necessary or otherwise determined to be appropriate by 
the POTW. Today's final rule also does not restrict POTWs' existing 
authority to use general control mechanisms to regulate facilities that 
are not considered Significant Industrial Users.
    What significant changes were made to the proposed rule?
    Today's rule makes the following changes to the proposed rule:
    Criteria for Coverage: In proposing the criteria for coverage under 
a general control mechanism, EPA omitted one of the criterion used in 
the NPDES general permit requirements. In today's final rule, EPA is 
adding this criterion, which is similar to 40 CFR 122.28(a)(2)(i)(E), 
to the list of criteria for coverage. The following language is 
included in 40 CFR 403.8(f)(1)(A)(5): ``in the opinion of the POTW, 
[the SIUs] are more appropriately controlled under a general control 
mechanism than under individual control mechanisms.''
    Request for Coverage: EPA has deleted all references to the 
requirement to submit a ``Notice of Intent'' (NOI) to be covered under 
a general control mechanism. The NOI is an instrument that is 
applicable to the NPDES general permit program. Although the proposal 
indicated that an alternative instrument could be used by the POTW, EPA 
has concluded that the ``written request for coverage'' better reflects 
the Agency's intention not to restrict the POTW's decision about the 
type of application it chooses to use in covering SIUs with a general 
control mechanism.
    Coverage for SIUs with Monitoring Waivers for Pollutants Not 
Present: EPA makes coverage under a general control mechanism available 
for SIUs which are requesting monitoring waivers for pollutants neither 
present nor expected to be present. The proposal did not state whether 
such facilities could still meet the required criteria for being 
considered substantially similar. EPA also specifies that the 
monitoring waiver is effective in the general control mechanism only 
after the SIU obtains written approval from the POTW that the 
monitoring waiver request has been approved.
    Coverage for SIUs with Mass Limits: The proposed rule excluded all 
facilities subject to mass limits from coverage under a general control 
mechanism. Today's final rule provides one exception to that exclusion. 
EPA clarifies in 40 CFR 403.8(f)(1)(iii)(A) that general control 
mechanisms are unavailable for facilities subject to categorical 
Standards expressed as mass of pollutant discharged. This language does 
not prevent a POTW from using a general control mechanism for a group 
of SIUs that all have the same mass-based local limits (as 
distinguished from mass-based categorical Standards), as long as the 
SIUs are not subject to categorical Standards that are mass-based. In 
addition, the final rule also clarifies that the mass-based categorical 
Standards excluded from coverage under a general control mechanism 
includes those limits that are expressed as mass of pollutant 
discharged per day or that are production-based.
    Recordkeeping Requirements: EPA is adding a requirement for the 
POTW to maintain for three years after the expiration of the general 
control mechanism, a copy of the general control mechanism itself, 
documentation to support the POTW's determination that the group of 
SIUs to be covered meets the required criteria, and copies of all 
related requests for coverage. This documentation will serve as a 
record for the POTW to support its actions in establishing the facility 
category and for authorizing coverage under the general control 
mechanism for individual facilities.
4. Summary of Major Comments and EPA Response
    Is use of a general control mechanism in conflict with EPA's 
original intent in requiring individualized control mechanisms for 
SIUs? One commenter expressed concern that using general control 
mechanisms would not provide the specificity of control over SIUs that 
the Domestic Sewage Exclusion (DSE) study (Report to Congress on the 
Discharge of Hazardous Wastes to Publicly Owned Treatment Works--EPA 
530-SW-86-004) indicated was necessary. Today's rule provides an 
exception to the requirement that the POTW issue SIUs ``permits or 
equivalent individual control mechanisms''. The commenter is correct in 
observing that the adoption of the requirement to issue control 
mechanisms to SIUs after EPA's issuance of the DSE study in 1986, was 
intended to provide a mechanism for the POTW to impose individualized 
Pretreatment requirements on SIUs. See 55 FR 30105-30110 (July 24, 
1990). However, EPA has now concluded that general control mechanisms 
can provide an equivalent level of control for facilities that meet all 
of the requirements in 40 CFR 403.8(f)(1)(iii)(1-6), and will not 
lessen the POTW's enforcement capabilities.
    Use of a general control mechanism does not relieve the POTW of any 
of its oversight or implementation requirements under its Pretreatment 
program. The purpose of the general control mechanism is to streamline 
the administrative requirements associated with issuing control 
mechanisms to multiple Industrial Users that are substantially similar. 
The level of control over an SIU with a general control mechanism 
should not be any different than if that User were covered by an 
individual control mechanism. Both individual and general control 
mechanisms must be enforceable and must contain the minimum conditions 
provided in 40 CFR 403.8(f)(1)(iii)(B)(1-6). In addition, EPA notes 
that it is within the POTW's discretion to exclude particular 
Industrial Users from general control mechanisms in order to treat 
those dischargers with more individually tailored requirements. EPA's 
intent is to leave these case-by-case determinations to the POTW, which 
should be in the best position to determine whether it is appropriate 
to use a general control mechanism for a particular User.
    Is a Notice of Intent (NOI) required for an SIU requesting coverage 
under a general control mechanism? Several commenters found EPA's use 
of the term ``Notice of Intent'' (NOI) problematic because it suggested 
that POTWs would be required to use such an instrument. These 
commenters requested that EPA delete the reference to NOI or make it 
clear that the POTW can choose the appropriate mechanism for SIUs to 
use in seeking coverage under a general control mechanism. EPA 
acknowledges these concerns, and has removed the reference to ``notice 
of intent'' in today's final rule. The revised rule instead refers only 
to a ``written request for coverage.'' The decision regarding the type 
of application to use for general control mechanisms is entirely the 
POTW's. EPA emphasizes, however, that regardless of the type of 
instrument chosen, the request for coverage must identify, at a 
minimum, the information required under new 40 CFR 403.8(f)(1)(iii)(A). 
POTWs must also request basic contact information (e.g., contact name, 
address, phone number, etc.) and specification of the general control 
mechanism category for which the SIU is seeking coverage. See 40 CFR 
403.8(f)(1)(iii)(A). The POTW will need to obtain sufficient 
information to verify that the User is appropriately classified under 
the general control mechanism, such as

[[Page 60146]]

information to determine the applicability of categorical Standards.
    Should there be additional criteria for a User to be eligible for 
coverage under a general control mechanism? One commenter requested 
that EPA include additional criteria for determining whether a group of 
Users are substantially similar enough to merit use of a general 
control mechanism. The criteria included in the proposal (e.g., that 
facilities to be covered involve the same or substantially similar 
types of operations, discharge the same types of wastes, require the 
same effluent limitations, and require the same or similar monitoring) 
are taken from the criteria used for general permits for direct 
dischargers in 40 CFR 122.28(a)(2)(i). The direct Discharge criteria 
contain one additional limitation, not included in the proposal, 
requiring the NPDES permitting authority to document that, in his or 
her opinion, the dischargers ``are more appropriately controlled under 
a general permit than under individual permits.'' See 40 CFR 
122.28(a)(2)(i)(E). In consideration of the commenter's request, and to 
be consistent with the criteria used for grouping direct dischargers 
within general permits, EPA has modified the proposed list of criteria 
to include a similar requirement that the POTW document why it believes 
that its SIUs are more appropriately regulated by a general control 
mechanism. EPA does not expect that this added criterion will impose 
additional burden on the POTW. This criterion merely requires that the 
POTW provide some written record of why it believes a particular 
grouping of SIUs is substantially similar, using the criteria in 40 CFR 
403.8(f)(1)(iii)(A)(1-5).
    Another commenter suggested that an SIU's compliance record should 
be used as an additional criterion for determining whether to allow 
general control mechanism coverage for a facility. EPA agrees that 
there will be factors, outside of the criteria in 40 CFR 
403.8(f)(1)(iii)(A), which may support a POTW's decision to exclude a 
particular Industrial User from general control mechanism coverage. EPA 
also agrees that the need to impose a compliance schedule or 
enforcement order on a particular Industrial User is a good example of 
an additional criterion that the POTW may use to exclude an SIU from 
general control mechanism coverage. EPA notes that the criteria listed 
in 40 CFR 403.8(f)(1)(iii)(A) are minimum requirements. The POTW may 
include additional criteria if it chooses. However, EPA is reluctant to 
add additional criteria at this time, as the Agency has concluded that 
many of these factors will be site-specific and are best left to the 
POTW to judge whether they are appropriate for use in their program.
    One commenter suggested that general control mechanisms not be 
available for SIUs that have multiple sampling locations, are subject 
to more than one categorical Standard, or have both federal categorical 
and non-categorical wastestreams. EPA agrees that situations such as 
this make it difficult to use a general control mechanism in some 
cases. However, EPA declines to adopt the additional criteria suggested 
by the commenter. The minimum required criteria in 40 CFR 
403.8(f)(1)(iii)(A) provide some flexibility regarding the availability 
of coverage for any particular User. EPA prefers to leave to the POTW 
the site-specific judgments as to whether a class of dischargers meets 
the substantially similar criteria. The POTW may determine that a User 
which has multiple sampling points or which is subject to both 
categorical Standards and non-categorical requirements is sufficiently 
dissimilar from other Users to justify precluding that discharger from 
general control mechanism coverage. There may be some instances where 
these differences may still be accommodated under a general control 
mechanism, and therefore EPA has concluded that eliminating this 
flexibility is inappropriate.
    Additionally, a general control mechanism may still be used to 
cover a class of Users subject to more than one categorical Standard as 
long as they are covered by the same Standards, in addition to meeting 
all other criteria for coverage. This is consistent with the 
requirement that all Users share the same effluent limits. See 40 CFR 
403.8(f)(1)(iii)(A)(3). However, EPA expects that where there is one 
User in the class which is subject to at least one different 
categorical Standard than the others, even if it has one or more 
categorical Standards in common with the other Users, such a User would 
be unable to obtain coverage under a general control mechanism covering 
the other Users due to the differences in effluent limits.
    Must the SIUs be exactly the same to be covered under a general 
control mechanism? Several commenters questioned EPA's intentions 
behind requiring that facilities meet the ``substantially similar'' 
criteria in order to qualify for use of a general control mechanism. 
Some of these commenters were concerned that the criteria would be 
interpreted too restrictively, and that industries would essentially 
have to be identical to be included in a general control mechanism 
group. One commenter believed that industries which are similar in many 
respects, but which are different in terms of operations and wastewater 
Discharges, should not be excluded from coverage.
    EPA's view is that the criteria for inclusion in a general control 
mechanism category are appropriate as stated. The opportunity to 
develop and issue the same control mechanism for multiple SIUs comes 
with the tradeoff that these industries share certain minimum 
characteristics. In response to the commenter's observation that 
general control mechanisms should be available for industries which are 
similar in many respects, but different in terms of operations and 
wastes discharged, EPA agrees and notes that the criteria require that 
the operations be ``the same or substantially similar'' and the 
Discharge be of ``the same types of wastes.'' EPA does not intend for 
these criteria to be interpreted as requiring the operations and wastes 
discharged to be exactly the same; rather, the intent is that 
industries covered under the same control mechanism be substantially 
similar.
    EPA acknowledges that industries are rarely the same in every 
respect. In order for an SIU to be included in a general control 
mechanism category, it must meet the criteria in 40 CFR 
403.8(f)(1)(iii)(A). With the exception of the SIU's effluent limits, 
which must be the same as other SIUs in the general control mechanism 
category, EPA does not expect each SIU in a general control mechanism 
category to be identical.
    Can a general control mechanism be used for facilities which obtain 
a monitoring waiver for pollutants neither present nor expected to be 
present? One commenter recommended that general control mechanisms not 
be made available for SIUs which receive a monitoring waiver for 
pollutants neither present nor expected to be present at the facility. 
The commenter reasoned that such facilities require individual control 
mechanisms due to the variation in sampling requirements from other 
facilities. EPA disagrees with the commenter. Categorical Industrial 
Users (CIUs) that qualify for a sampling waiver for pollutants neither 
present nor expected to be present can still be accommodated under a 
general control mechanism even if other Users in the same general 
control mechanism category are still required to sample for all 
pollutants. There is flexibility inherent in the criterion requiring 
all industries covered by a general control mechanism to be subject to 
the ``same or similar monitoring''. If a particular CIU

[[Page 60147]]

is similar in every other respect to other CIUs, except for a sampling 
waiver for pollutants neither present nor expected to be present, it is 
EPA's view that a general control mechanism may still be used to cover 
this discharger. However, a POTW could choose as a matter of its own 
discretion to exclude CIUs with sampling waivers from coverage under 
the general control mechanism.
    To assist the POTW in coordinating the implementation of general 
control mechanisms and processing requests for monitoring waivers, EPA 
is requiring Users to include in their requests for general control 
mechanism coverage any sampling waiver requests. Such a requirement 
will ensure that the POTW is able to process both the sampling waiver 
request and the general control mechanism application simultaneously, 
and provide the POTW with sufficient opportunity to determine what type 
of control mechanism is most appropriate. Where the POTW chooses to 
still cover those CIUs which receive monitoring waivers under a general 
control mechanism, 40 CFR 403.8(f)(1)(iii)(A) specifies that the 
monitoring waiver is effective only after the POTW has specifically 
notified the affected CIUs. Also, because all control mechanisms must 
include SIU self-monitoring requirements, unless all of the monitoring 
requirements and waivers for all pollutants are the same, the POTW will 
need to establish a common set of monitoring requirements in a general 
control mechanism and determine what mechanism it will use to 
incorporate site-specific monitoring waivers into a general control 
mechanism. Some possible mechanisms for addressing facility-specific 
monitoring waivers include issuing a separate monitoring supplement to 
the general control mechanism for individual CIUs, using the waiver 
approval notice as a site-specific modification to the general control 
mechanism, or appending the general control mechanism with specific 
monitoring waivers. See Section III.A. for discussion of requirements 
associated with monitoring waivers.
    Can an SIU opt out of an existing general control mechanism? 
Several commenters expressed opinions on one side or the other in terms 
of whether general control mechanisms can be made mandatory or optional 
by the POTW. Industrial facilities generally commented that EPA should 
prevent POTWs from making general control mechanisms mandatory, while 
POTW commenters supported keeping this decision a matter of the local 
program's discretion. EPA is sensitive to the concerns regarding the 
need for flexibility on the type of control mechanism used for 
individual SIUs. The industry commenters argue that the SIU should be 
able to choose whether it wants to be covered by an individual or 
general control mechanism. EPA does not specify in today's rule whether 
the use of general control mechanisms should be optional or mandatory. 
However, provided that the SIUs in a category meet the required 
criteria, the POTW has the discretion to determine whether coverage 
under the general control mechanism is required or whether the 
Industrial User will have the option of being covered under an 
individual control mechanism. EPA emphasizes that there should be 
minimal if any difference between an individual and general control 
mechanism since the POTW is required to include in a general control 
mechanism all of the conditions of individual control mechanism listed 
in 40 CFR 403.8(f)(1)(iii)(B)(1)-(6). Even if the POTW chooses to make 
general control mechanism coverage mandatory, the SIU may be able to 
demonstrate to the POTW that it does not meet one of the criteria and 
therefore should be issued an individual control mechanism.

C. Best Management Practices (40 CFR 403.5, 403.8(f) and 403.12(b), 
(e), and (h))

    Today's final rule clarifies that Best Management Practices (BMPs) 
may be used in lieu of numeric local limits. EPA also clarifies the 
reporting requirements that apply when BMPs are used as Pretreatment 
Standards.
1. What are the existing rules?
What are Best Management Practices?
    Best Management Practices (BMPs) are management and operational 
procedures that are intended to prevent pollutants from entering a 
facility's wastestream or from reaching a Discharge point. BMPs are 
distinguished from numeric effluent limits that regulate the pollutants 
once they enter a wastestream. Although the General Pretreatment 
Regulations have not previously defined BMPs, the NPDES regulations at 
40 CFR 122.2 define BMPs as schedules of activities, prohibitions of 
practices, maintenance procedures, and other management practices to 
prevent or reduce pollution. BMPs also include treatment requirements, 
operating procedures, and practices to control plant site runoff, 
spillage or leaks, sludge or waste disposal, or drainage from raw 
material storage.
    There are two different circumstances in which BMPs may be 
Pretreatment Standards. The first is when a POTW establishes BMPs as 
local limits to implement the general and specific prohibitions. The 
second is when the BMPs are categorical Pretreatment Standards 
established by EPA.
What regulations address the use of BMPs as local limits?
    Prior to today's rule, the Pretreatment Regulations did not 
specifically address the use of BMPs as local limits. Thus, 40 CFR 
403.5(c) required POTWs to develop ``specific limits'' and ``specific 
effluent limits'', without defining the term ``limits.'' (emphasis 
added)
    The Local Limits Development Guidance (EPA 833-R-04-002A, July 
2004) includes a discussion in support of BMPs as local limits, and 
provides references and case studies to illustrate situations where 
BMPs have been utilized. EPA indicates also that the development and 
implementation of numeric local limits is not always the only 
appropriate or practical method for preventing pollutant Pass Through 
and Interference, or for protecting POTW worker health and safety. For 
instance, control of chemical spills and Slug Discharges to the POTW 
through formal chemical or waste management plans can go a long way 
toward preventing problems. A local requirement for an Industrial User 
to develop and submit such a plan can be considered as a type of 
narrative local limit and can be a useful supplement to numeric limits.
What regulations address the use of BMPs as categorical Standards?
    Certain categorical Pretreatment Standards allow the use of BMPs as 
an alternative means of complying with, or in place of the established 
numeric effluent limit. For example, facilities may develop toxic 
organic management plans in lieu of sampling to demonstrate compliance 
with the total toxic organic limit in 40 CFR Part 433 (Metal Finishing 
category). The Pesticides Formulating, Packaging, and Repackaging 
(PFPR) regulation provides a pollution prevention alternative as an 
option that may be chosen rather than complying with the ``zero 
discharge'' limitations. See 40 CFR Part 455 (61 FR 57518, November 6, 
1996).
    Although the PFPR and some other categorical Standard regulations 
have provided for reporting compliance data related to BMPs, the Part 
403 Pretreatment Regulations did not. See 40 CFR 403.12(b), (d), and 
(e). Those requirements focused on sampling data to demonstrate 
compliance with numeric limits rather than

[[Page 60148]]

documentation to determine compliance with a BMP.
2. What changes did EPA propose?
    EPA proposed to clarify the regulations to provide specifically 
that BMPs developed by POTWs may serve as local limits required by 40 
CFR 403.5(c)(3). The BMPs would be enforceable under 40 CFR 403.5(d). 
They would be included as local control mechanism requirements under 40 
CFR 403.8(f)(1)(iii)(C).
    EPA also proposed to modify 40 CFR 403.12(b), (e), and (h) to 
clarify the reporting requirements that apply when BMPs are used as 
Pretreatment Standards. This would include any documentation required 
by the Control Authority or the Standards themselves to demonstrate 
compliance with BMPs that are included in categorical Standards, as 
well as any documentation required by the Control Authority to 
demonstrate compliance with BMPs that serve as local limits. EPA also 
proposed a change to the definition of significant noncompliance (SNC) 
to facilitate POTW oversight of these practices. The proposal would 
broaden the SNC definition at 40 CFR 403.8(f)(2)(vii)(C) to include 
non-numeric violations such as BMPs. In addition, EPA proposed to 
revise the reference to ``pretreatment effluent limit'', and replace it 
with the more inclusive reference to ``Pretreatment Standard or 
Requirement''.
3. What changes is EPA adopting today?
    Today's rule adopts the proposed rule changes to the Pretreatment 
Regulations relating to the use of BMPs as local limits, and the 
reporting requirements when BMPs are used as national categorical 
Standards.
What significant changes were made to the proposed rule?
    The only significant change made to the proposed rule was the 
inclusion in 40 CFR 403.3(e) of a definition of BMPs consistent with 
the NPDES definition.
4. Summary of Major Comments and EPA Response
    Does the CWA authorize POTWs to require implementation of BMPs as 
local limits? A few commenters questioned the authority under the CWA 
for POTWs unilaterally to require Industrial Users to implement BMPs 
instead of or in addition to numeric local limits. POTW authority to 
establish limits and other controls on Discharge derives from state 
law, not the CWA. The Act, together with the Pretreatment Regulations, 
specifies authorities that POTWs must have, and establishes the 
conditions under which local requirements become federally enforceable. 
There is nothing under the Act that would preclude POTWs from setting 
BMP-based limits, or EPA from making such limits established by a POTW 
federally enforceable.
    How are BMPs defined? Several commenters felt that the use of the 
NPDES definition of BMPs would be appropriate in the Pretreatment 
context. EPA agrees that such a definition would be useful, and is 
adopting the NPDES definition, modified slightly to reference relevant 
Pretreatment Standards.
    Is a regulatory change needed for BMPs developed by POTWs to be 
considered enforceable local limits? Some commenters expressed the view 
that BMPs could already serve as enforceable local limits, and that a 
regulatory change was unnecessary. As discussed in the preamble to the 
proposal, the existing regulations do not specifically address this 
issue, although EPA has supported their use in its local limits 
guidance. EPA has concluded that revision of the regulations is 
necessary to clear up any questions on this issue. As will be discussed 
below, by providing this clarification EPA is ensuring that POTWs have 
additional means at their disposal as they seek to control pollutants 
and sources not amenable to more traditional numeric limits.
    Will POTWs be limited in their ability to develop BMPs as local 
limits? Some commenters recommended that the POTW's ability to use BMPs 
as local limits be limited to certain situations, such as where it is 
impracticable to obtain representative sampling data from a type of 
discharger, the Discharge flow is minimal or variable, or where 
operations or processes of a type of discharger are similar enough that 
effective BMPs can be established. In general, EPA anticipates that 
POTWs will choose to use BMPs instead of numeric local limits where 
determination of compliance with numeric limits is infeasible, or as a 
supplement to numeric limits as appropriate to meet the requirements of 
the CWA. As the commenters pointed out, BMPs may be appropriate for 
regulating releases when the types of pollutants vary greatly over 
time, when chemical analyses are impracticable, and when other 
Discharge control options are inappropriate. It may also be appropriate 
for IUs to be required to comply with both BMPs and numeric limits. 
While use of BMPs is not appropriate in all situations, their use, 
either in conjunction with or instead of numeric limits, will be at the 
discretion of the POTW, with oversight by EPA and the state Approval 
Authority.
    What are some specific situations where BMPs would be appropriate? 
Numerous commenters representing POTWs, Industrial Users and trade 
associations provided specific examples where BMPs would be well-suited 
to address certain types of industrial or commercial Discharges, either 
in lieu of or in addition to numeric local limits. Examples involving 
requirements for photoprocessors to use silver recovery systems and/or 
management practices were frequently cited to address silver Discharges 
from large numbers of commercial facilities. Also cited were 
requirements for dental facilities to follow BMPs to control mercury 
Discharges from dental amalgam where individual monitoring on a large 
scale is impractical and where Discharges are episodic in nature. 
Similarly, other commenters referred to use of shop towel management 
and other BMPs to address Discharges from printing facilities, or 
setting requirements for ``no Discharge'' of tetrachloroethene from dry 
cleaning facilities as an alternative to complying with a numeric 
limit. The Agency agrees that these are good examples of situations 
where BMPs may be appropriate.
    BMPs may also be used to supplement categorical Standards or 
numeric local limits at larger facilities. One commenter described the 
use of chemical management plans to address specific pollutants in 
individual IU Permits. These plans, which were required by the POTW, 
require IUs to identify within 60 days of Permit issuance all sources 
of a given pollutant within the plant site; specify actions to be taken 
to control these identified sources; provide a schedule for 
implementing the plan; and identify individuals responsible for 
implementation of the plan. Upon approval by the POTW, the chemical 
management plan is incorporated into the IU's Permit as an enforceable 
requirement.
    Who decides whether a POTW will require an IU to comply with a BMP 
or numeric limit? Some industries and trade associations asked EPA to 
ensure that IUs have the option of whether to meet BMPs or numeric 
limits. While POTWs are encouraged to work with affected Users in 
developing local limits, and must comply with applicable public 
participation requirements, the POTW is responsible for developing, 
implementing and enforcing local limits as it deems appropriate to meet 
its program requirements. As discussed above, whether BMPs are used in 
conjunction with or instead of numeric

[[Page 60149]]

limits will be at the discretion of the POTW, upon approval by the 
Approval Authority.
    How are BMPs factored into the technical evaluation of local 
limits? The preamble to the proposed rule stated that for BMPs to be 
considered local limits under 40 CFR 403.5(c), the practices must 
protect against Pass Through and/or Interference. This will require the 
POTW to evaluate the BMPs during the technical evaluation of its local 
limits. Some commenters raised questions regarding whether a POTW would 
need to quantify the effects of a BMP in its calculation of its maximum 
allowable industrial loading (MAIL), and if so, how that should be 
done.
    As discussed in the preamble to the proposal, BMPs are expected to 
be used where calculation of numeric effluent limitations is not 
feasible, such as when the types of pollutants vary over time or when 
chemical analyses are inappropriate. Nevertheless, a POTW needs to 
assign an allocation of pollutants to Users covered by the BMP either 
in its calculation of Maximum Allowable Industrial Loadings (MAIL), or 
in calculation of separate allowable loadings for commercial 
facilities. For instance, a POTW could estimate the loading of a 
pollutant from a given sector prior to imposition of BMPs by 
multiplying the average loading per User by the number of facilities. 
Expected loading reductions from required BMPs could then be estimated 
and incorporated into the MAIL. Thus, the POTW should be able to 
provide an evaluation that implementation of the numeric limit plus 
implementation of BMPs for specific sectors will result in the 
calculated Maximum Allowable Headworks Loading (MAHL) being met. Where 
it is expected to take a significant amount of time for BMP-based 
reductions to be realized, the Apre-BMP'' loading from the sector 
should be used in the MAIL calculations. Initial estimates of loading 
reductions could then be verified through sampling of selected Users 
that have implemented the BMPs or evaluating influent loadings for 
pollutants being addressed by BMPs to see if adjustments are needed for 
the allowable headworks loadings, the numeric limits or BMPs for any 
affected sectors.
    May States and EPA Regions establish BMPs as local limits? One 
commenter observed that the language in 40 CFR 403.5(c)(4), allowing 
POTWs to develop BMPs as local limits, would not pertain to states that 
administer authorized Pretreatment programs. The commenter supported 
broadening this language to allow authorized states and Regions, acting 
in their capacity as Control Authorities, to develop and enforce BMPs. 
Section 40 CFR 403.5(d), states that ``where specific prohibitions or 
limits on pollutants (i.e., local limits) are developed by a POTW in 
accordance with (40 CFR 403.5(c)), such limits shall be deemed 
Pretreatment Standards for the purposes of section 307(d) of the Act.''
    An authorized state which does not approve POTW programs but 
assumes local responsibility by acting as the Control Authority under 
40 CFR 403.10(e) is required to implement all elements of the 
Pretreatment program established for POTWs in 40 CFR 403.8(f), 
including the establishment of local limits (40 CFR 403.8(f)(4)). Local 
numeric limits or BMPs established in this situation would be federally 
enforceable Pretreatment Standards under 40 CFR 403.5(d) provided such 
limits are authorized by state law.
    An authorized state acting as the Approval Authority, and as 
Control Authority for Industrial Users which discharge to a POTW 
without an approved program, may develop and implement BMPs or other 
local limits applicable to those Industrial Users provided such limits 
are authorized by state law. In the case where EPA acts as the Approval 
Authority and Control Authority, for a local limit to be federally 
enforceable under 40 CFR 403.5(d), the limit would need to be 
incorporated into the local POTW's sewer use ordinance or other legal 
authority.
    What are some of the common elements of an enforceable BMP? Many 
commenters expressed the view that without additional guidance on the 
structure of BMPs, their use could be subjective and difficult to 
evaluate or enforce. Others felt that because of their subjective and 
potentially arbitrary nature, BMPs should not be allowed to serve as 
local limits. BMPs developed by a POTW to protect against Pass Through 
and Interference can be structured in such a manner that compliance 
with their terms can be verified by a POTW, and can provide a useful 
alternative to numeric limits in situations where such limits are 
infeasible or impractical. In addition, BMPs established by POTWs as 
local limits will be subject to oversight from the POTW's state and EPA 
Region. These BMPs will be evaluated by states and EPA based on factors 
such as legal authority, effectiveness, and enforceability.
    Based on EPA's experience and observations of situations where BMPs 
have been effective, enforceable BMPs should generally include the 
following elements. Depending on the sector being controlled, however, 
certain elements such as installation of treatment or prohibitions on 
practices may not be applicable.
    <bullet> Specific notice to IUs of requirements and enforceability. 
This notice, provided through POTW sewer use ordinances or individual 
or general control mechanisms, should make clear which Users are 
subject to the BMPs, and what affected Users must do to comply with 
their requirements.
    <bullet> Installation of treatment. POTWs should provide criteria 
or specifications that the equipment must satisfy. For example, a 
requirement for use of oil/water separators at auto repair facilities 
could include sizing or design criteria. EPA cautions POTWs to avoid 
endorsing the use of specific brands or vendors.
    <bullet> Requirements for or prohibitions on certain practices, 
activities or Discharges. POTWs should include specific requirements or 
prohibitions where necessary to ensure that the use of such BMPs is 
protective. An example would be a prohibition on Discharges of 
tetrachloroethene from dry cleaning facilities.
    <bullet> Requirements for operation and maintenance (O&M) of 
treatment units. POTWs should spell out their O&M expectations to 
ensure that treatment systems continue to perform as designed and 
installed. For example, restaurants could be required to have grease 
interceptors cleaned out at a specified frequency.
    <bullet> Timeframes associated with key activities. POTWs should 
provide timeframes for when management practices must be implemented, 
or when required treatment must be installed and fully operational. 
Other milestones should be added to the schedule where necessary to 
facilitate the oversight of BMP implementation.
    <bullet> Compliance certification, reporting and records retention. 
Establishing specific procedures for such requirements will enable 
POTWs to verify whether required equipment has been installed, or 
whether required maintenance has been performed at the specified 
frequency.
    <bullet> Provision for re-opening or revoking the BMP conditions. 
As with numeric limits, POTWs should include language in the sewer use 
ordinance and/or facility control mechanisms that enables them to 
revoke the control mechanism at any time to include modified numeric 
limits or BMPs. For example, the POTW may find it necessary to revoke 
an Industrial User's control mechanism where the POTW determines that 
the User has not complied with applicable BMPs, or where the POTW 
determines

[[Page 60150]]

that it is easier to determine compliance with a numeric limit.
    <bullet> Other requirements as determined by the POTW.
    What local legal authority changes will be necessary? POTWs wishing 
to establish BMPs instead of or in addition to numeric local limits 
will need to evaluate their sewer use ordinances to ensure they provide 
adequate authority to require compliance with BMPs by affected Users. 
Further, BMP requirements such as those discussed above, and which IUs 
they cover, should be specified in POTW sewer use ordinances and/or 
Industrial User control mechanisms.
    How will compliance and significant noncompliance be determined? 
Concerns were expressed regarding the ability of Control and Approval 
Authorities to determine whether a User is in compliance with BMPs. In 
EPA's view, BMPs that set specific requirements, incorporating as 
appropriate the common elements presented above, (i.e., requirements or 
prohibitions on practices, activities or Discharges; requirements for 
installation, operation and maintenance of treatment units; timeframes 
for key activities; reporting and records retention; certification and 
reporting of compliance, etc.) will aid POTWs and Approval Authorities 
in their compliance determinations. Once these requirements are 
established for one or more facilities in a sector, an IU's compliance 
status should be able to be verified through a combination of self-
reporting and verification inspections. Where a facility subject to 
BMPs has not satisfied the requirements in the sewer use ordinance or 
control mechanism, the POTW would need to use its enforcement response 
plan (ERP) to determine the appropriate response, and relevant 
significant noncompliance criteria to assess whether the facility is in 
significant noncompliance. For example, a facility that fails to 
install required treatment equipment within a specified timeframe would 
generally be viewed as being in significant noncompliance 90 days after 
the schedule date. See 40 CFR 403.8(f)(2)(vii)(E). Likewise, a facility 
would be in significant noncompliance if it failed to submit a 
compliance certification within 45 days from the due date. See 40 CFR 
403.8(f)(2)(vii)(F). POTWs adopting BMPs as local limits, or that have 
Categorical Industrial Users whose categorical Standards include BMPs, 
should evaluate their ERPs to ensure that they reflect the need to 
enforce non-numeric requirements.

D. Slug Control Plans (40 CFR 403.8(f)(1)(iii)(B)(6) and 
403.8(f)(2)(vi))

    Today's final rule addresses the requirement that POTWs evaluate 
the need for a slug control plan for SIUs every two years. The rule 
will provide POTWs with the flexibility to determine how frequently to 
evaluate the need for such plans, based on local conditions. At the 
same time, the new rule specifies that an evaluation must be undertaken 
for each SIU once within a specified timeframe. Today's rule also 
clarifies that an actual slug control plan (e.g., the physical document 
itself) is not the POTW's only option for controlling facilities with a 
higher potential for Slug Discharges. The regulation states that the 
POTW may choose to require that the SIU take specific, preventative 
actions instead of requiring the development of a slug control plan. 
Regardless of the requirements imposed by the POTW, today's rule will 
require that where actions to control Slug Discharges are determined to 
be necessary, the SIU's control mechanism must include provisions 
addressing those requirements.
    These revisions do not alter current requirements regarding annual 
monitoring and inspections of SIUs. POTWs are still required to conduct 
their annual facility inspections and effluent monitoring for each of 
their SIUs. The revisions also do not change the POTW's requirement to 
prevent disruptions caused by Slug Discharges. EPA expects that, as an 
integral part of its ongoing oversight of all SIU facilities, the POTW 
will consider whether adequate measures are in place to avoid Slug 
Discharges. The POTW is authorized to use its own discretion in 
determining the timing, level of detail, and commitment of resources 
necessary to ensure the facility has adequate measures in place to 
protect against Slug Discharges. POTWs may still require the SIU to 
develop a slug control plan or take specified preventative measures to 
prevent Slug Discharges whenever the facility's slug control measures 
are judged to be inadequate.
    Today's rule does not impose any new requirements on Industrial 
Users. SIUs remain subject to current requirements to eliminate or 
mitigate the effects of a Slug Discharge. These actions may include 
constructing physical containment facilities as well as implementing 
sound management practices to prevent Slug Discharges.
1. What were the rules in place prior to today's rulemaking?
    A Slug Discharge is defined as ``* * * any Discharge of a non-
routine, episodic nature, including but not limited to an accidental 
spill or non-customary batch Discharge'' (40 CFR 403.8(f)(2)(v)). EPA 
notes that the subparagraph numbers have changed slightly in the final 
rule due to other, unrelated modifications. The appropriate rule 
reference is now 40 CFR 403.8(f)(2)(vi). The regulations require POTWs 
to ensure that Industrial Users have policies and procedures in place 
to prevent or mitigate the effects of Slug Discharges. Section 40 CFR 
403.8(f)(2)(v), prior to today's rulemaking, required POTWs to ``* * * 
evaluate, at least once every two years, whether each such Significant 
Industrial User needs a plan to control Slug Discharges.'' The function 
of such a plan is to ensure that an SIU has a planning and 
implementation tool to prevent Interference at a POTW treatment 
facility by a non-routine or accidental Discharge. The minimum elements 
required in a slug control plan are (1) a description of Discharge 
practices, (2) a description of all stored chemicals at the facility, 
(3) procedures for immediately notifying the POTW of the Slug Discharge 
and providing written follow-up notification, and (4) a variety of 
procedures (e.g., inspection and maintenance of chemical storage areas) 
for preventing adverse impacts from any accidental spills (40 CFR 
403.8(f)(2)(v)(A) to (D)).
    The requirement for a once every two years review of the need for a 
slug control plan was part of the Domestic Sewage Study rulemaking (55 
FR 30082, July 24, 1990). In the preamble discussion to that 
rulemaking, EPA explained the need for POTWs to implement slug control 
programs. As part of the discussion, EPA referenced the guidance 
manual, Control of Slug Loadings to POTWs (EPA 21W-4001, February 1991, 
see http://www.epa.gov/npdes/pubs/owm021.pdf), which was then under 
preparation. This manual provides detailed guidance for POTWs to 
evaluate whether SIUs need to develop slug control plans. It also 
provides guidance for SIUs in developing those slug control plans. In 
addition, the manual recognizes that POTWs need to determine whether 
existing on-site conditions may impact their treatment works, while 
industries are in the best position to solve problems relative to their 
physical plants or production processes. Part 403 requires that, where 
found to be necessary, a POTW must require an SIU to develop a plan or 
impose some specified control actions to prevent Slug Discharges.

[[Page 60151]]

2. What changes did EPA propose?
    The proposed rule suggested eliminating the requirement that POTWs 
evaluate the need for a slug control plan for each SIU every two years. 
Instead, EPA proposed giving POTWs the flexibility to review the need 
for slug control plans or other actions as part of their ongoing 
oversight of Industrial Users. The proposal would have added language 
to clarify that requiring an actual slug control plan is one of several 
options the POTW has at its disposal for controlling facilities with a 
higher potential for Slug Discharges. The proposed rule would have 
clarified that a POTW could choose to require that the SIU take certain 
specified preventative actions to control the Slug Discharge potential, 
instead of developing a slug control plan. In addition, to ensure that 
slug controls are enforceable to the same extent as other Standards and 
requirements, the proposal would have added language to require that, 
where a slug control plan or other action is found to be necessary, 
appropriate requirements would be placed in the Industrial User's 
control mechanism.
3. What changes is EPA finalizing in today's rule?
    In today's final rule, consistent with the proposal, EPA removes 
the required minimum frequency for conducting POTW evaluations for the 
need for slug control plans or other control actions. The final rule 
also formalizes the requirement for SIUs to address Slug Discharges by 
requiring that the POTW include language in the User's control 
mechanism to control Slug Discharges, if it determines that a slug 
control plan or other action is necessary. These rule revisions appear 
in 40 CFR 403.8(f)(1)(iii)(F) and 403.8(f)(2)(vi).
What significant changes were made to the proposed rule?
    Today's rule makes the following changes to the proposed rule:
    Minimum evaluation frequency: Today's rule specifies that POTWs 
must evaluate at least once the SIU's need for a slug control plan or 
other action to control Slug Discharges. See 40 CFR 403.8(f)(2)(vi). 
While the POTW may choose how frequently to assess slug-related 
concerns, it is EPA's view that it is important to impose a minimum 
frequency of one time per SIU to ensure that each SIU receives at least 
one thorough evaluation. The provision specifies that this evaluation 
must have occurred within one year of the effective date of today's 
rule for SIUs identified as significant (yet never evaluated for the 
need for a slug control plan) prior to the rule's effective date. Also, 
SIUs identified as significant after the effective date of the rule 
must be evaluated for the need for a slug control plan within one year 
of being identified as significant.
    Notification of significant facility change: EPA also adds a 
requirement that SIUs must notify the POTW immediately of any changes 
at their facilities, not already addressed in their slug control plan 
or other slug control requirements, which may affect the potential for 
a Slug Discharge. This requirement is especially relevant in the case 
of those Users for which the POTW has determined, from some prior 
assessment, that a slug control plan or other action is unnecessary. 
However, EPA emphasizes that this requirement affects all SIUs, even 
those that already have slug control plans or other measures in place. 
See 40 CFR 403.8(f)(2)(vi). This provision places an affirmative duty 
on such Users to provide the POTW with updated information on the 
potential slug risks that are posed by industrial process changes. This 
provision is consistent with, but differs from the existing 
notification of changed Discharge in 40 CFR 403.12(j), which focuses on 
advance notice of change in the volume or character of pollutants in 
the Discharge itself.
4. Summary of Major Comments and EPA Response
    The following summarizes the major comments received and EPA's 
response.
    Should POTWs be required to conduct annual inspections of SIUs to 
determine the adequacy of slug control plans? One commenter supported 
the proposed rule change, but recommended adding language to require 
the POTW to verify during an inspection that a slug control plan, if 
required, is adequate. EPA agrees with the commenter that the POTW 
should be assessing the adequacy of existing slug control plans during 
its annual inspection of SIUs. However, EPA has not included a specific 
requirement in the regulation to this effect since existing inspection 
and sampling guidance already recommend that POTWs assess the adequacy 
of slug control plans during the POTW's annual inspection.
    EPA emphasizes that this provision does not affect the POTW's 
requirements to conduct inspections of its SIUs, nor has EPA changed 
its recommendations about how to assess slug-related issues at each 
facility. According to EPA's Industrial User Inspection & Sampling 
Manual for POTWs (1994) (http://www.epa.gov/npdes/pubs/owm0025.pdf), 
POTW inspectors should ask SIU staff if they are familiar with slug 
control procedures, and request that a copy of the slug control plan be 
provided for an assessment of its adequacy. EPA's guidance document 
Control of Slug Loadings to POTWs (1991) (http://www.epa.gov/npdes/pubs/owm021.pdf) recommends that inspectors verify compliance with slug 
control requirements and plans (see p. 2-44). In addition, EPA's slug 
loading guidance indicates that ``the inspector should ascertain the 
Industrial User's status with regard to compliance with the Plan, 
report any deficiencies observed in the Industrial User's current Plan, 
and suggest alternatives or modifications'' (see p. 2-44).
    Can existing control measures or planning documents substitute for 
slug control plan requirements at SIU facilities? Several commenters, 
while supporting the proposal, requested that EPA clarify that existing 
spill containment procedures or plans may adequately fulfill the 
Pretreatment requirements concerning slug control plans. EPA agrees 
with the commenter that there will be situations where existing 
containment and spill planning documents at an Industrial User facility 
describe adequate means for protection against Slug Discharges. EPA 
recognizes that a number of existing requirements under other statutes 
and regulations could serve as components of slug control plans. For 
example, Spill Prevention, Control, and Countermeasures (SPCC) plans 
may address some components of a slug control plan. A POTW could also 
consult existing Emergency and Hazardous Chemical Inventory reports 
(EPCRA Section 312, 40 CFR 370) typically submitted to local fire 
marshals or other Local Emergency Planning Committee offices for the 
facility. If an SIU is covered by any of these pre-existing plans, the 
POTW may accept such plans in partial or complete fulfillment of the 
slug control requirements, as long as each element set forth in 40 CFR 
403.8(f)(2)(vi)(A)-(D) is addressed in an acceptable manner in some 
document or collection of documents, and a reference to the need to 
comply with these procedures is included in the User's control 
mechanism pursuant to 40 CFR 403.8(f)(1)(iii)(F). However, EPA notes 
that many of these pre-existing plans have been developed for purposes 
other than control of Slug Discharges to POTWs, and the POTW must 
carefully review the plans to ensure that they

[[Page 60152]]

meet the requirements of a slug control plan and the needs of the POTW.
    In summary, under today's rule, a POTW has the discretion to 
determine, based on an initial inspection or previous evaluations, that 
existing procedures and control measures at the facility make the 
development of a slug control plan unnecessary. The POTW should 
document this finding as part of its records, and, consistent with 
existing EPA guidance, should annually assess the adequacy of these 
existing procedures and control measures as part of its annual 
inspections. Also, implementation of these procedures or control 
measures should be included as requirements in the facility's control 
mechanism.
    How should the POTW determine how often to conduct evaluations at 
individual facilities concerning whether a slug control plan is needed? 
One commenter pointed out that how frequently a POTW should evaluate 
the need for a slug control plan may vary for different facilities. The 
commenter emphasized that at some facilities, conducting such an 
evaluation once every two years may not be sufficient. Regarding the 
commenter's concerns about the frequency of Slug Discharge evaluations, 
under today's rule, each POTW will need to determine what evaluation 
frequency is appropriate for its program and/or for individual 
facilities. EPA also recommends that POTWs consult with the Agency's 
guidance document, Control of Slug Loadings to POTWs (1991) (http://www.epa.gov/npdes/pubs/owm021.pdf), which suggests different ways to 
prioritize industrial facilities according to Slug Discharge potential 
and strategies for assessing the adequacy of existing plans and 
programs. To ensure that POTWs are provided with sufficient notice of a 
change in Slug Discharge potential, EPA has added an additional 
requirement for SIUs which are not required to develop a slug control 
plan to notify the POTW immediately of any changes at their facilities 
affecting the need for plans or other actions to address Slug 
Discharges. It is EPA's position that placing the affirmative duty on 
the SIUs to notify the POTW of such changes further reduces the 
potential for Slug Discharge in the time between on-site inspections.
    Although supporting the proposal, several commenters suggested that 
EPA adopt further criteria for determining when a slug control plan is 
necessary at an individual facility. Among the suggested criteria were 
the following: (1) Slugs from an industrial facility violated the 
Pretreatment requirements or otherwise harmed the POTW; or (2) the 
amount of stored materials, the absence of sufficient secondary 
containment, and the proximity of drains to the sewer create a 
significant risk of a harmful slug. EPA agrees with the commenter in 
general that criteria suggesting when a slug control plan should be 
developed would assist POTWs in making this decision. On the other 
hand, EPA decided that it should not develop rigid criteria in its 
regulation establishing when slug control plans should be required.
    EPA emphasizes that a POTW is in the best position to make such 
determinations and, since such requirements will help ensure continued 
compliance with its NPDES Permit, it is in the interest of the POTW to 
do so. However, in lieu of providing a list of strict criteria, EPA 
suggests that POTWs and SIUs consult the Agency's guidance document, 
Control of Slug Loadings to POTWs (1991) (http://www.epa.gov/npdes/pubs/owm021.pdf), for recommendations on significant factors and types 
of industries to consider in determining which facilities pose a 
greater risk of Slug Discharge, and, therefore, should be required to 
develop a slug control plan. For instance, the guidance document 
highlights the following as the most significant factors to consider: 
Quantity and types of materials used or stored at an IU and their 
potential for causing violation of local limits or the general or 
specific prohibitions; potential for such materials to enter the sewer 
system and cause damage (i.e., whether control measures are in place); 
and adequacy of existing controls to prevent any potential slug loading 
(see p. 2-19). EPA points out, though, that the guidance also clarifies 
that these evaluations should be conducted on a plant-by-plant basis 
and that the list of factors and target industries provides 
generalizations from which to start. (see p. 2-7).
    In response to the commenter's recommended criteria, EPA agrees 
that facilities which have had Slug Discharges, thus violating the 
Pretreatment Requirements or otherwise harming the POTW, will need a 
slug control plan. The slug control plan requirements were adopted to 
provide POTWs with a mechanism to prevent slug-related impacts. EPA is 
concerned that this criterion may suggest to POTWs that it is 
sufficient to wait for circumstances to arise (e.g., an instance of 
Interference at the treatment plant) before addressing the need for a 
slug control plan at a potentially higher risk facility. EPA does not 
agree that the only situations where an SIU should be required to 
develop a slug control plan are those where a violation of the POTW's 
Pretreatment program requirements has occurred. Part of what the POTW 
must evaluate at each SIU is whether there is the ``reasonable 
potential'' for Interference or Pass Through from a Slug Discharge, 
thereby necessitating a slug control plan or other preventative action. 
EPA suggests that waiting for a violation to occur before requiring a 
slug control plan conflicts with the proactive intent behind 40 CFR 
403.8(f)(2)(vi) and may result in unnecessary Interference or Pass 
Through occurrences.
    EPA does agree that the commenter's second suggested criterion, 
that the amount of stored materials, the absence of sufficient 
secondary containment, and the proximity of drains to the sewer create 
a significant risk of a harmful slug, would be appropriate POTW 
considerations for requiring the development of a slug control plan. 
These considerations are contemplated in the above referenced guidance.
    How does the rule affect the current practice of evaluating SIUs 
annually for the adequacy of slug controls? A few commenters were 
opposed to the proposal because they considered it to be unnecessary. 
These commenters emphasized the limited burden imposed by the current 
biannual review requirement and the current practice of conducting 
annual SIU inspections which focus on, among other things, the adequacy 
of controls or existing plans for addressing the potential for Slug 
Discharges. Another commenter objected to the proposal because of 
concern that POTWs would no longer dedicate the necessary attention to 
evaluating SIU facilities for the potential for Slug Discharges.
    The evaluation of slug control procedures and measures is already 
occurring at POTWs on an annual basis, typically during the inspection 
of the SIU. This practice is consistent with EPA's guidance document, 
Industrial User Inspection and Sampling Manual for POTWs (1994) (http://www.epa.gov/npdes/pubs/owm0025.pdf). EPA's modification of the 
frequency of the POTW's evaluation of the necessity of slug control 
plans should not affect the POTW's practice of conducting annual 
inspections of relevant slug control procedures and measures. The final 
rule changes do not absolve POTWs from the requirement to prevent 
disruptions caused by Slug Discharges. In many instances, operating 
conditions at an SIU will not have changed significantly since the 
issuance of its individual control mechanism and the facility will be 
in compliance with all of its Permit conditions. Under these 
circumstances,

[[Page 60153]]

the requirement to review and evaluate the need for a slug control plan 
or other preventative actions could be an unproductive use of resources 
by the POTW. In addition, today's revision to 40 CFR 403.8(f)(2)(vi) 
requires that each POTW evaluate the need for a slug control plan or 
other action at least one time at every SIU. Following this evaluation, 
the POTW may determine its own schedule for conducting further 
evaluations for the need for a plan.
    In practical terms, EPA expects POTWs to take the following actions 
with regard to Slug Discharges: Evaluate all of their SIUs at least 
once for the need for a slug control plan, conduct follow-up 
evaluations for facilities not required to develop a slug control plans 
or take other actions as necessary, and inspect each SIU annually to 
determine the adequacy of and compliance with existing procedures and 
control measures. While today's revision may reduce the administrative 
resources currently devoted to biannual reviews for the need for a slug 
control plan, the POTW's overall level of oversight over Slug 
Discharges will not be reduced.
    EPA also points out that Approval Authority audits and Pretreatment 
Compliance Inspections (PCIs) of POTW Pretreatment Programs will offer 
a valuable opportunity to evaluate how today's revisions are being 
implemented. During these audits or PCIs, the POTW will need to 
demonstrate that each SIU has been evaluated at least once (or that 
there is a plan to conduct such an evaluation within the coming year). 
EPA suggests that where a slug control plan or other action was not 
deemed necessary, a plan to re-evaluate the SIU for the need for a plan 
or other action as necessary exists. The POTW may choose a specified 
frequency level to re-evaluate the SIU, or it may choose to re-evaluate 
the facility following a notification of changed Discharge pursuant to 
40 CFR 403.12(j) or 40 CFR 403.8(f)(2)(vi). EPA notes that SIUs will 
now be required to notify the POTW of any changes at their facility 
that affect the need for a slug control plan or other actions to 
address Slug Discharges, although POTWs still have the responsibility 
during the facility inspections to ensure that these notifications have 
been made. In addition, during the audit or PCI, the Approval Authority 
should determine whether the POTW is conducting an assessment of the 
SIU's on-site procedures and measures to control for potential slug-
related Discharges.
    Does the slug control plan, if required, need to be included in the 
SIU's control mechanism? One commenter was opposed to what it 
interpreted as EPA's requirement in 40 CFR 403.8(f)(1)(iii)(B)(6) to 
include the entire slug control plan document in the SIU's control 
mechanism. The commenter further emphasized that the slug control plan 
should be retained as a separate document, and suggested that the plan 
be incorporated by reference into the control mechanism requiring 
compliance with the approved plan.
    EPA disagrees with the commenter as far as reading 40 CFR 
403.8(f)(1)(iii)(B)(6) to require the inclusion of the entire slug 
control plan in the SIU's control mechanism. Section 
403.8(f)(1)(iii)(B)(6) provides that the control mechanism must include 
``requirements to control Slug Discharges.'' EPA expects that POTWs 
will include language in the control mechanism that requires control of 
Slug Discharges, rather than the terms of a particular SIU's plan. 
Including the entire slug control plan may prove to be administratively 
burdensome since changes made to the plan during the term of the 
control mechanism would potentially require that the control mechanism 
be modified, or be reopened and reissued.

E. Equivalent Concentration Limits for Flow-Based Standards (40 CFR 
403.6(c)(6))

    Today's amendment to the Pretreatment Regulations authorizes the 
use of concentration-based limits in lieu of flow-based mass limits for 
the facilities in the Organic Chemicals, Plastics, and Synthetic Fibers 
(OCPSF) (40 CFR part 414), Petroleum Refining (40 CFR part 419), and 
Pesticide Chemicals (40 CFR part 455) categories. The Control Authority 
may use the concentration limits listed in the categorical Pretreatment 
Standards for these three categories as an alternative to the current 
requirement to convert those concentration limits to flow-based mass 
limits. Control Authorities establishing concentration-based 
Pretreatment Standards instead of mass-based limits must document that 
dilution is not being used as a substitute for treatment (see 
Sec. Sec.  403.6(d), 414.111(a), 419, and 455). Additionally, the 
Control Authority is required to adjust Permit limits using the 
combined wastestream formula in Sec.  403.6(e) when the wastestream 
used for demonstrating compliance with the Permit limits is mixed with 
non-process wastewater or wastewater from other processes.
1. What are the current rules?
What is a flow-based mass limit?
    National categorical Pretreatment Standards establish limits on 
pollutants discharged to POTWs by specific industrial sectors. The 
Standards establish limitations on the amount of pollutants to be 
discharged by individual dischargers in different ways for different 
categories. The regulations establishing Pretreatment Standards for new 
and existing indirect dischargers in the Organic Chemicals, Plastics, 
and Synthetic Fibers Category (OCPSF), for new indirect dischargers in 
the Petroleum Refining category, and for new and existing indirect 
dischargers in the Pesticide Chemicals category currently require 
limits of certain pollutants to be expressed in terms of mass, based on 
the promulgated concentrated-based Standards and the average daily flow 
rate of the Industrial User's regulated process wastewater (see 
Sec. Sec.  414.111(a), 419.17(b), 419.27(b), 419.37(b), 419.47(b), and 
419.57(b), 455.26, 455.27). For an OCPSF indirect discharger, a 
pesticide chemicals indirect discharger, or a new petroleum refining 
indirect discharger, the Control Authority develops a mass limit by 
multiplying the applicable pollutant concentration that EPA promulgated 
in the effluent guidelines (expressed in terms of mass of pollutant per 
volume of Discharge) by the average daily flow rate of the Industrial 
User's regulated process wastewater (expressed in terms of volume per 
day). The result is a Permit limit on the mass of pollutants per day 
(see 58 FR 36890, July 9, 1993).
    The average daily flow rate should be based upon a reasonable 
measure of the Industrial User's average daily flow for at least a 30-
day period (see 40 CFR 403.6(e)(1)). Additionally, EPA ``strongly urges 
the Control Authority to develop an appropriate process wastewater flow 
for use in computing the mass effluent or internal plant limitations 
based on water conservation practices,'' (see 58 FR 36890, July 9, 
1993). Finally, a Permit may be modified during its term, either at the 
request of the permittee (or another interested party) or on the 
Control Authority's initiative, to increase or decrease the flow basis 
in response to a significant change in production (40 CFR 124.5, 
122.62). A change in production could be an ``alteration'' of the 
permitted activity or ``new information'' that would provide the basis 
for a Permit modification (40 CFR 122.62(a)(1),(2)) (see 58 FR 36891, 
July 9, 1993).
Why was the mass limit approach developed?
    Effluent guidelines may be specified in a number of ways including 
production normalized (mass-pollutant/production unit) and 
concentration-

[[Page 60154]]

based limitations (mass-pollutant/volume of wastewater). These two 
types of effluent guidelines limits can be converted to a mass-based 
Standard by using a reasonable measure of the Industrial User's actual 
long-term daily production (for production normalized limitations) or 
the Industrial User's actual long-term average daily flow rate (for 
concentration-based limitations). EPA prefers setting production 
normalized limitations, where feasible, since production normalized 
limitations can require flow reduction and reduces any potential for 
the substitution of dilution for treatment. Specifically, production 
normalized limitations are calculated from production normalized flows 
(volume of wastewater/ production unit) and incorporate wastewater flow 
reductions representing Best Available Technology Economically 
Achievable (BAT) (technology basis for Pretreatment Standards for 
Existing Sources, or PSES) or New Source Performance Standards 
(technology basis for Pretreatment Standards for New Sources, or PSNS).
    EPA has established concentration-based Standards when production 
and achievable wastewater flow cannot be correlated nationally. EPA has 
explained how to calculate a mass limit in the Organic Chemicals, 
Plastics, and Synthetic Fibers (OCPSF) regulation. A mass limit is 
developed from the concentration-based Standard by multiplying the 
promulgated Pretreatment Standard (expressed as a concentration) by the 
Industrial User's actual long-term average daily flow rate. This 
approach re-enforces the requirements of the combined wastestream 
formula (see 40 CFR 403.6(e)) to minimize the potential for dilution of 
process wastewaters by non-process wastewater. The combined wastestream 
formula of Section 403.6(e) applies to indirect dischargers where 
process wastewater is mixed prior to treatment with wastewater other 
than that generated by the regulated process.
What are the problems with mass limits based on flow?
    Flow-based mass limits can, however, be difficult for the Control 
Authority to implement. To develop a flow-based mass limit, the Control 
Authority must determine the average daily flow rate of the Industrial 
User's regulated process wastewater and then multiply that value by the 
appropriate promulgated concentration Standard. This may be difficult 
in situations where the facility has highly variable production that 
leads to flows that often vary week-to-week or day-to-day. This is 
especially true for smaller facilities where: (1) The average daily 
flow rate of the Industrial User's regulated process wastewater may be 
infrequent or low and difficult to monitor; and (2) production tends to 
be more variable as the installation of equipment to provide flow 
equalization may not be practical.
    In addition, testing for compliance with the flow-based mass limit 
requires having accurate information on the flow from all regulated 
processes at the time the sample is taken. Testing for compliance with 
a concentration limit only requires taking the wastewater sample and 
comparing the sampled concentration to the limit. In particular, since 
promulgation of the OCPSF Pretreatment Standards, there have been 
difficulties in getting Control Authorities and OCPSF facilities to 
correctly calculate flow-based mass limits, and to provide necessary 
data to determine compliance with the Standards. Deficiencies in 
Permits and control mechanisms have in the past hindered enforcement 
actions against these facilities. Enforcing mass-based Standards also 
becomes more complicated because there is an additional factor in the 
formula to calculate mass-based limits. In order to measure compliance, 
both flow and concentration of the pollutant need to be accurate and 
verified in order to produce legally enforceable mass-based results.
May alternative limits be developed for flow-based categorical 
Standards?
    Currently, 40 CFR 403.6(c) allows Control Authorities to apply an 
equivalent concentration limit in addition to a current mass limit to 
implement a Pretreatment Standard. However, the regulations do not 
allow equivalent concentration limits in lieu of mass limits when the 
Pretreatment Standard requires a mass limit to be calculated from the 
promulgated concentration-based Standards and the average daily flow 
rate of the Industrial User's regulated process wastewater.
2. What changes did EPA propose?
    EPA proposed to allow Control Authorities to use promulgated 
concentration-based limits instead of flow-based mass limits in 
establishing limits for Industrial Users in the OCPSF, Petroleum 
Refining, and Pesticide Chemicals categories. EPA proposed that the 
Control Authority would be allowed to apply such equivalent 
concentration limits only if the flow from the facility is so variable 
that the development of mass limits is impractical. EPA stipulated that 
40 CFR 403.6(d) would continue to prohibit facilities from increasing 
flow in order to meet their concentration limits through dilution.
3. What changes is EPA finalizing in today's final rule?
    The final rule allows Control Authorities to use concentration-
based limits instead of flow-based mass limits for new and existing 
indirect dischargers in the OCPSF category, new indirect dischargers in 
the Petroleum Refining category, and new and existing indirect 
dischargers in the Pesticide Chemicals category. EPA is not limiting 
the Control Authority's authority to develop concentration limits to 
circumstances in which the Control Authority determines that the 
facility's flow is ``so variable as to make mass limits 
impracticable.'' EPA notes that Section 40 CFR 403.6(d) will continue 
to prohibit facilities from increasing flow in order to meet their 
concentration limits through dilution. As with other concentration 
limits, the Control Authority should be certain that dilution is not 
occurring and that the Discharge represents regulated process 
wastewater flows. The concentration may need to be adjusted using the 
combined wastestream formula in 40 CFR 403.6(e) if the wastestream is 
mixed with non-process wastewater or wastewater from other processes.
    New 40 CFR 403.6(c)(6), applicable only to facilities in the OCPSF, 
Petroleum Refining, and Pesticide Chemicals categories, requires 
Control Authorities to document that dilution is not being substituted 
for treatment. To verify that equivalent concentration limits are not 
subsequently being met through use of dilution flows, Control 
Authorities should note that 40 CFR 403.12(e)(1) requires Categorical 
Industrial Users to provide information regarding maximum and average 
daily flows in their periodic reports, and enables them to require more 
detailed flow data as necessary. Using this authority, EPA recommends 
that Control Authorities consider specifying appropriate flow 
monitoring requirements and including evaluation of flow data in the 
review of periodic reports for Industrial Users subject to equivalent 
concentration Standards. This will enable Control Authorities to 
determine if there have been changes in flows that may indicate 
dilution, such as increases in process, non-process or overall flows, 
especially those not accompanied by production increases.
When are the equivalent concentration limits effective?
    EPA notes that flow-based mass Standards, like all National 
categorical Pretreatment Standards, are self-

[[Page 60155]]

implementing for new and existing indirect dischargers in the OCPSF 
category and for new indirect dischargers in the Petroleum Refining 
category. Facilities to which these Standards are applicable must 
comply with the flow-based mass Standards unless a Permit or other 
control mechanism is issued by the Control Authority which establishes 
equivalent concentration limits under 40 CFR 403.6(c)(6). Where the 
Control Authority has not issued a control mechanism that establishes 
categorical concentration-based limits, the Industrial User must comply 
with the default flow-based mass limits as established in the 
applicable categorical Pretreatment Standard.
    EPA notes that, for the Pesticides Chemicals category, in certain 
circumstances, an Industrial User may already be subject to 
concentration based limits rather than the otherwise required mass 
limits. Where the Control Authority has not established flow-based mass 
limits as required, Sections 40 CFR 455.26 and 455.27 provide that 
Industrial User must comply with the default concentration-based limits 
as established in the categorical Pretreatment Standard.
    EPA emphasizes that for facilities in the OCPSF, Petroleum 
Refining, and Pesticide Chemicals categories, where the Control 
Authority has properly authorized the use of an equivalent 
concentration limit and has incorporated that limit into the Industrial 
User's control mechanism, the concentration limit replaces the mass 
limit. The final rule requires that an Industrial User must comply with 
the equivalent limit in lieu of the promulgated categorical 
Pretreatment Standard once the limit is incorporated into its control 
mechanism. The Control Authority may also determine that an Industrial 
User should be subject to both the flow-based mass limit as well as the 
concentration-based limit. When incorporated into the issued control 
mechanism, the Industrial User would have to comply with both limits. 
As with other equivalent concentration limits, as currently provided in 
40 CFR 403.6(c), the equivalent limits being authorized under today's 
final rule are Pretreatment Standards for the purposes of Sec. 307(d) 
of the Clean Water Act and are federally enforceable.
4. Summary of Major Comments and EPA Response
    A majority of the commenters supported the proposed rule as 
written, and most of the remaining commenters stated qualified support. 
Only one commenter opposed the proposal. The following section 
summarizes the most significant comments received and EPA's response.
    Is Approval Authority review required of an Industrial User's 
proposed concentration limit prior to Control Authority approval? A 
total of 22 commenters disagreed that it would be appropriate to 
require Approval Authority review of an Industrial User's proposed 
concentration limit prior to Control Authority approval. The primary 
reasoning stated was that such a requirement is not necessary and would 
create additional burden.
    EPA notes that this provision is intended to allow the permit limit 
to be expressed in alternate units. It is not anticipated that this 
revision will change the Control Authority's enabling legislation to 
issue and enforce a control mechanism. As such, EPA does not consider 
this provision to be a modification of a POTW Pretreatment Program 
under 40 CFR 403.18, and, therefore, finds that a POTW's use of this 
provision is not subject to the specified approval procedures in this 
section. The new equivalent limit is subject to review as part of 
routine Approval Authority oversight activities, such as a Pretreatment 
Compliance Inspection or a Control Authority audit. In accordance with 
current regulations, Industrial User control mechanisms and information 
necessary for determining permit limitations and compliance must be 
publicly available.
    Is this provision limited to highly variable flows? Numerous 
commenters addressed the question of whether this provision should only 
be applied to highly variable flows as well as how to define the term 
``highly variable flow.'' A total of 12 commenters stated that the rule 
should not be limited to only highly variable flows. Many mentioned the 
existence of factors in addition to highly variable flows that make 
implementation of flow-based mass limits impractical, such as the cost 
of obtaining accurate samples or the difficulty of sampling at 
facilities with very low flows. Ten commenters suggested that the 
Control Authority have the ability to define ``highly variable flows'' 
on a case-by-case basis since the basis for such a determination is 
highly site-specific and can vary from seasonal variations in flow to 
hourly variations in flow. Ten commenters thought that a 20 percent 
deviation from average flow is an adequate measure for ``highly 
variable flow,'' while five commenters requested that EPA not specify a 
definition for ``highly variable flow'' in the regulations.
    EPA acknowledges that the there are numerous factors, many of which 
are site-specific, involved in determining that a facility has ``highly 
variable flow(s)'', and agrees that it would be difficult to establish 
a clear-cut definition of ``highly variable flow'' that would apply to 
all facilities. To be consistent with the goals of providing 
flexibility in this rule, and to support the Control Authority's 
discretion on this site specific issue, EPA has decided to allow 
Control Authorities to determine when the acceptable circumstances 
exist to allow the use of concentration limits.
    Is this provision consistent with the Clean Water Act? The 
commenter that opposed this provision stated that EPA lacks the 
authority to create a variance or an alternative implementation 
mechanism and therefore will violate sections 307 and 402 of the Clean 
Water Act. The commenter also questioned the need for this proposed 
change, suggested that it will interfere with ongoing enforcement of 
the categorical Standards and the statutory deadlines for achieving 
them, and suggested that the record does not demonstrate that this 
proposed change will protect POTWs and the environment.
    EPA is promulgating the changes to its Pretreatment Regulations in 
part under section 307(b) of the Clean Water Act. Section 307(b) 
clearly authorizes EPA from time to time to revise Pretreatment 
Standards as ``control technology, processes, operating methods or 
other alternatives change.'' Therefore, today's action is not in 
violation of section 307(b) to the extent this provision amends the 
Pretreatment Standards for the OCPSF, the Petroleum Refining, and the 
Pesticide Chemicals Categories. As EPA has explained, the amendments to 
the regulations will facilitate both User's compliance and POTW 
oversight. EPA notes that compliance evaluation and enforcement will be 
more straightforward and less burdensome with new equivalent 
concentration limits.
    Moreover, the current regulations prohibit introduction of 
pollutants that will adversely affect POTW operations and receiving 
waters quality. Currently, 40 CFR 403.5 requires approved pretreatment 
programs and POTWs receiving pollutants from Industrial Users with 
potential to pass through or interfere with the POTWs' operations to 
develop and implement local limits to protect the POTW operations and 
prevent Pass Through and Interference. Consequently, the use of 
concentration limits in lieu of mass limits would not be authorized if 
it resulted in a violation of local limits approved under 40 CFR 403.5. 
Furthermore, this provision may be implemented only following

[[Page 60156]]

determination of its feasibility by Control Authorities, and not 
unilaterally by Industrial Users. Control Authorities' local limits 
will continue to ensure protection of the POTW operations and its 
receiving environment.

F. Use of Grab and Composite Samples (40 CFR 403.12(b), (d), (e), (g), 
and (h))

    This section discusses: (1) The application of minimum required 
grab samples for pH, cyanide, total phenols, oil and grease, sulfide, 
and volatile organics to the periodic compliance reports; (2) when a 
time-proportional sample may be used instead of a flow-proportional 
sample; (3) when multiple grab samples may be composited prior to 
analysis; (4) whether four grab samples are required whenever grab 
sampling is appropriate; and (5) the sampling of facilities that 
discharge less than 24-hours per day. Other issues raised by commenters 
are also discussed.
1. What are the existing rules?
What are ``grab samples''?
    A grab sample is ``* * * a sample which is taken from a wastestream 
without regard to the flow of the wastestream and over a period of time 
not to exceed 15 minutes'' (Industrial User Inspection and Sampling 
Manual for POTWs, EPA 831/B-94-001, April 1994, http://www.epa.gov/npdes/pubs/owm0025.pdf). Grab samples of volatile organic compounds 
(VOCs) must be collected almost instantaneously (i.e., less than 30 
seconds of elapsed time) and properly preserved (Comparison of Volatile 
Organic Analysis Compositing Procedures, EPA 821/R-95-035, September 
1995). An analysis of an individual grab sample provides a measurement 
of pollutant concentrations in the wastewater at a particular point in 
time. Grab samples are usually collected manually, but can be obtained 
with a mechanical sampler.
    Grab samples are required in order to accurately analyze those 
pollutant parameters that may be affected by biological, chemical, or 
physical interactions and/or exhibit marked physical and compositional 
changes within a short time after collection. Grab samples should be 
used when: (1) Wastewater characteristics are relatively constant; (2) 
parameters to be analyzed are likely to be affected by the compositing 
process, such as the procedures used for oil and grease; (3) composite 
sampling is infeasible or the compositing process is liable to 
introduce artifacts of sampling; and (4) the parameters to be analyzed 
are likely to change with storage. In particular, accurate 
determination of pH, temperature, total phenols, oil and grease, 
sulfide, volatile organic compounds, and cyanide requires properly 
collecting and carefully preserving grab samples.
What are composite samples?
    A composite sample is formed by mixing discrete samples or 
``aliquots.'' For a ``flow-proportional'' composite sample, each 
individual aliquot is collected after the passage of a defined volume 
of Discharge (e.g., every 2,000 gallons). For a ``time-proportional'' 
composite sample, the aliquots are collected after the passage of a 
defined period of time (e.g., once every two hours), regardless of the 
volume or variability of the rate of flow during that period. Flow-
proportional compositing is usually preferred when effluent flow volume 
varies appreciably over time. The number of discrete samples necessary 
for a composite sample to be representative of the Discharge depends 
upon the variability of the pollutant concentration and the flow.
    Automatically collected composite samples are usually preferred to 
collecting grab samples and then manually compositing the grabs into a 
single sample. Possible handling errors made during the compositing 
process could yield a sample that is not truly representative of the 
Discharge. However, composite samples can be prepared from manually 
collected grab samples if each grab contains a fixed volume that is 
retrieved at intervals that correspond to the periods of wastewater 
Discharge or time of the facility's operation.
When may the requirement for flow-proportional composite samples be 
waived?
    The regulations in effect prior to today's rule allowed Control 
Authorities to waive the requirement for flow-proportional compositing 
of samples for baseline monitoring reports and 90-day compliance 
reports in limited circumstances. These regulations allowed the Control 
Authority to accept sample data that are obtained from time-
proportional composite sampling or a minimum of four grab samples if 
flow-proportional sampling is infeasible (e.g., the facility cannot 
accurately measure flow) and the Industrial User demonstrated that 
these alternative sampling techniques will provide a representative 
sample of the effluent (40 CFR 403.12(b)(5)(iii)). The section on 
periodic compliance reports was silent on the subject of grab and flow-
proportional sampling.
2. What changes did EPA propose?
    EPA proposed to clarify the sampling requirements in 40 CFR 403.12 
in the following ways:
    Do the sampling requirements apply to periodic reports on continued 
compliance? EPA proposed to extend the requirements of 40 CFR 
403.12(b)(5)(iii), which were explicitly applicable to the baseline 
monitoring reports and 90-day reports required by 40 CFR 403.12(b) and 
(d), to the periodic reports required in 40 CFR 403.12(e) and (h). 
These changes would be accomplished by consolidating the new 
requirements for all of the reports in 40 CFR 403.12(g). Redundant 
sections would be removed.
    Is a minimum frequency required for grab samples? EPA proposed that 
for periodic monitoring reports, a minimum of four grab samples would 
not need to be taken in all instances to measure pH, cyanide, total 
phenols, oil and grease, sulfides, and volatile organic compounds. 
Instead, Control Authorities would have the flexibility to determine 
the appropriate number of grab samples required for periodic compliance 
reports. For new facilities, the Industrial User would still be 
required to take a minimum of four grab samples to measure pH, cyanide, 
total phenols, oil and grease, sulfide, and volatile organic compounds 
to meet baseline monitoring and 90-day compliance report requirements. 
For existing facilities, where historical sampling data are available, 
the Control Authority may authorize a lower minimum.
    When and what type of grab samples can be manually composited? EPA 
proposed to explicitly state that compositing of certain types of grab 
samples prior to their analysis would be permitted.
    When can time-proportional or grab samples be used in lieu of flow-
proportional composite samples? EPA proposed that Control Authorities 
may authorize time-proportional or grab sampling in lieu of flow-
proportional sampling as long as the samples are representative of the 
Discharge.
    What are the sampling requirements for those facilities that do not 
discharge continuously? EPA proposed language intended to clarify that, 
although a ``24-hour composite sample'' must be taken within a 24-hour 
period, the sample should only be collected during that portion of the 
24-hour period that the Industrial User is discharging from the 
regulated process and/or from the treatment unit.

[[Page 60157]]

3. What changes are being finalized by EPA in today's rule?
    EPA is finalizing language intended to clarify the sampling 
requirements in 40 CFR 403.12. Specific changes to the regulations, as 
well as pertinent details related to their implementation, are 
discussed below.
    Do the sampling requirements apply to periodic compliance reports? 
Today's rule finalizes the extension of sampling requirements, which 
previously were only explicitly applicable to the baseline monitoring 
reports and 90-day reports required by 40 CFR 403.12(b) and (d), to the 
periodic reports required in 40 CFR 403.12(e) and (h). These changes 
are accomplished by consolidating the new requirements for all of the 
reports in 40 CFR 403.12(g). Redundant sections are removed.
    Is a minimum frequency required for grab samples? The final 
regulatory changes eliminate the requirement that a minimum of four 
grab samples be taken in all instances to measure pH, cyanide, total 
phenols, oil and grease, sulfides, and volatile organic compounds. 
Control Authorities will have the flexibility to determine the 
appropriate minimum number of grab samples Industrial Users are 
required to take. The Control Authorities will be responsible for 
documenting the site-specific circumstances in the Industrial User's 
file. New facilities and facilities that make changes or install new 
treatment are still required to take a minimum of four grab samples to 
measure pH, cyanide, total phenols, oil and grease, sulfide and 
volatile organic compounds to meet baseline monitoring and 90-day 
compliance report requirements. For facilities where historical 
sampling data are available, the Control Authority may authorize a 
lower minimum number of grab samples.
    There are some cases where a single grab sample can be reasonably 
expected to be representative of a Discharge. Appendix V to the EPA 
guidance (Industrial User Inspection and Sampling Manual for POTWs, EPA 
831/B-94-001, April 1994, http://www.epa.gov/npdes/pubs/owm0025.pdf) 
lists cases where a single grab sample may appropriately be substituted 
for a single composite sample, including small batch Discharges. For 
example, a homogeneous batch Discharge is consistent with existing 
guidance on the appropriate use of a single grab sample.
    When and what type of grab samples can be manually composited? 
Today's final rule clarifies that multiple grab samples for cyanide, 
total phenols, sulfide, oil and grease, and volatile organic compounds 
collected during a 24-hour period may be composited prior to analysis. 
Control Authorities also will be allowed to authorize manually 
composited grab samples for other parameters that are unaffected by 
compositing procedures. Using protocols (including appropriate 
preservation) specified in 40 CFR Part 136 and appropriate EPA 
guidance, EPA clarifies in the rule that multiple grab samples 
collected during a 24-hour period may be composited prior to the 
analysis as follows: for cyanide, total phenols, and sulfides, the 
samples may be composited in the laboratory or in the field; for 
volatile organics and oil and grease, the samples may be composited in 
the laboratory.
    It is important that a composite sample provides an accurate 
representation of the pollutant in the wastewater. The composite sample 
should provide analytical results that are comparable to averaged 
results of the individual grab samples taken over a specific time 
interval. In all cases where a series of grab samples is manually 
composited, those parameters that have preservation requirements in 40 
CFR Part 136 must be properly preserved and/or stored at the time of 
collection as required by the specific analytical method employed prior 
to compositing. In addition, EPA wishes to reaffirm that some 
pollutants are not amenable to the compositing process. For example, 
total residual chlorine, pH, and temperature samples cannot be 
``composited'' under any circumstances because the results would be 
changed by the compositing process. Today's final rule does not allow 
Control Authorities to authorize composite samples for these 
parameters.
    Although analytical procedures for compositing oil and grease 
samples have been developed, the general consensus among laboratory 
experts is that current techniques do not provide consistently reliable 
results. However, continuing advances in analytical technology may 
provide methodologies that will make accurate compositing of oil and 
grease samples technically less cumbersome and more cost effective in 
the future. Under today's rule, the Control Authority has the 
flexibility to allow Industrial Users to submit data from composited 
oil and grease samples as long as the samples were composited in the 
laboratory and the sampling and analytical procedures used are 
sanctioned by EPA in 40 CFR Part 136.
    EPA guidance (Industrial User Inspection and Sampling Manual for 
POTWs, EPA 831/B-94-001, April 1994, http://www.epa.gov/npdes/pubs/owm0025.pdf) describes procedures for manually compositing individual 
grab samples that will provide accurate results. The reader should also 
consult the regulations in 40 CFR Part 136 to identify the accepted 
analytical protocols for specific classes of compounds or individual 
parameters. A separate guidance manual (Comparison of Volatile Organic 
Analysis Compositing Procedures, EPA 821/R-95-035, 1995, http://www.epa.gov/clariton/clhtml/pubtitleOW.html) discusses procedures for 
accurate compositing of volatile organic compounds.
When can time-proportional or grab samples be used in lieu of flow-
proportional composite samples?
    Today's final rule will allow Control Authorities to waive the 
requirement that Industrial Users collect flow-proportional samples. 
The regulation no longer requires Control Authorities to require the 
Industrial User to demonstrate that flow-proportional samples are 
``infeasible.''
    The Industrial User must demonstrate that the time-proportional or 
grab samples are representative of the Discharge before the Control 
Authority may allow the Industrial User to submit such samples. Where 
time-proportional composite sampling or grab sampling is authorized by 
the Control Authority, the samples must be representative of the 
Discharge and the decision to allow the alternative sampling must be 
documented in the individual Industrial User records for that facility. 
The use of statistical approaches to determine representativeness may 
be appropriate in certain circumstances. See for example, the March 2, 
1989, Office of Water Regulations and Standards (OWRS) Memorandum to 
Region 9 describing the results of a statistical analysis of sampling 
data from a single industrial facility. Refer to http://www.epa.gov/region09/water/pretreatment/program_impl.html. In addition to 
demonstrating that the samples are representative, the Control 
Authority must ensure that compliance samples are taken with sufficient 
care to produce evidence admissible in enforcement proceedings or in 
judicial actions as required by the section modified today at 40 CFR 
403.8(f)(2)(vii).
What are the sampling requirements for those facilities that do not 
discharge continuously?
    As will be discussed below in the response to comments section, the 
final rule does not include the sentence in the proposed rule that 
read, ``For those

[[Page 60158]]

Industrial User Discharges subject to categorical Pretreatment 
Standards that do not operate on a 24-hour per day schedule, the 
samples must be collected at equally spaced intervals during the period 
that process wastewater is being discharged.'' EPA interprets a ``day'' 
to be a 24-hour period which does not have to occur within a calendar 
day. This interpretation is consistent with the definition of ``daily 
discharge'' in the NPDES regulations at 40 CFR 122.2. Daily discharge 
means the ``discharge of a pollutant'' measured during a calendar day 
or any 24-hour period that reasonably represents the calendar day for 
purposes of sampling. During parts of the day when there is no 
discharge of process wastewater, standing water should not be 
disproportionately sampled and analyzed as it would not be 
representative of the Discharge from the facility. As always, the 
Control Authority must prescribe a sampling protocol that produces 
representative results. The selected protocol should take into 
consideration all of the operation conditions and the physical 
configuration of the Industrial User facility.
What significant changes were made to the proposed rule?
    EPA did not make significant changes to the proposed rule. The 
changes made from the proposal to the final rule include minor wording 
changes, a clarification to compositing methods, the reinstatement of a 
sentence that was removed in the proposal, and the removal of a 
sentence from the proposal.
    The changes (other than minor wording changes intended to provide 
clarification) are as follows:
    The following sentence, which had been deleted in the proposal, is 
returned to the regulations: ``The Control Authority shall require that 
frequency of monitoring necessary to assess and assure compliance by 
Industrial Users with applicable Pretreatment Standards and 
Requirements.'' (EPA notes that non-significant CIUs (NSCIUs) may 
satisfy this requirement through certification.) This sentence had been 
taken out in the proposed rule. However, because the sentence adds 
clarity, EPA has decided to retain it. The rationale is discussed in 
the response to comments section below.
    The following sentences at 40 CFR 403.12(g)(3) were removed from 
the regulations: ``For those Industrial User Discharges subject to 
categorical Pretreatment Standards that do not operate on a 24-hour per 
day schedule, the samples must be collected at equally spaced intervals 
during the period that process wastewater is being discharged. Multiple 
grab samples for cyanide and volatile organic compounds that are 
collected during a 24-hour period may be composited in the laboratory 
prior to analysis using protocols specified in 40 CFR Part 136 and 
appropriate EPA guidance.'' The rationale is discussed in the response 
to comments section below.
    For parameters that require grab sampling, EPA explicitly states 
which parameters may be composited in the field and the laboratory and 
which parameters may only be composited in the laboratory. This 
addition further clarifies the issue of compositing for samples that 
require collection by grab methods in order to preserve sample 
integrity.
4. Summary of Major Comments and EPA Response
    Commenters were generally supportive of the sampling changes that 
EPA proposed. Some of the comments requested further clarification of 
issues. The following section summarizes EPA's response to these 
comments.
    Will the final rule on compositing increase workload for sampling 
personnel? A commenter stated that manually compositing cyanide and 
volatile organics samples should be avoided for sample integrity and 
workload increase.
    Regardless of whether multiple grab samples are individually 
analyzed or composited, samples must be properly preserved. Therefore, 
any workload change will likely occur at the laboratory, and increased 
workload for compositing the sample would be offset by decreased 
workload for analysis. EPA further clarifies in the final rule which 
parameters currently may be composited in the laboratory and which ones 
may be composited in the field. Under the current EPA-approved methods, 
oil and grease, and volatile organics may only be composited in the 
laboratory. Whether samples are composited in the lab or the field, 
sample integrity must be preserved, including preserving each grab 
sample in accordance with 40 CFR Part 136.
    May Industrial Users determine the appropriate sampling flexibility 
without Control Authority approval? Industrial Users commented that EPA 
should give more flexibility to Industrial Users to determine what 
sampling schemes are appropriate for their facility. EPA disagrees. 
Control Authorities are responsible for ensuring that compliance 
samples are taken with sufficient care to produce evidence admissible 
in enforcement proceedings or in judicial actions as required by 40 CFR 
403.8(f)(2)(vii) and for ensuring compliance by IUs with Pretreatment 
Standards and Requirements. To the extent that sampling is 
representative of the Discharge, the Control Authorities will be able 
to determine the appropriate sampling flexibility. The Control 
Authorities retain the responsibility for documenting site-specific 
circumstances and allowing alternate sampling by including the 
alternate sampling in the Industrial User control mechanisms.
    May Control Authorities determine the appropriate number of grab 
samples for baseline monitoring and 90-day compliance reports? EPA 
requested comment on whether Control Authorities should be allowed the 
flexibility to determine the appropriate number of grab samples 
required to meet baseline monitoring and 90-day compliance report 
requirements for facilities without historical sampling data. 
Commenters supported the proposal to eliminate the requirement that a 
minimum of four grab samples be taken to measure pH, cyanide, total 
phenols, oil and grease, sulfides, and volatile organic compounds. 
Commenters stated that Control Authorities should be given flexibility 
to determine the appropriate number of grab samples required to meet 
reporting requirements, but did not provide concrete reasons as to how 
this would ensure that the sampling was representative of the 
Discharge.
    EPA stresses that the flexibility should only be provided to the 
extent that the sampling is representative. The Control Authority will 
be responsible for documenting site-specific circumstances and allowing 
alternate sampling in the Industrial User control mechanisms. Baseline 
Monitoring Reports (BMRs) will likely provide the first samples for a 
parameter, and 90-day compliance reports will provide samples after any 
treatment has been added. Therefore, it is likely that at a minimum 
this data will be needed in order to document that alternative sampling 
is representative. Because it is unlikely that a Control Authority 
could properly document that sampling is representative without data 
from BMRs and 90-day compliance reports, EPA retains the requirement 
for a minimum of four grab samples for BMRs and 90-day compliance 
reports in order to document potential future sampling decisions for 
new facilities. For existing facilities where there is historic data 
representative of the current Discharge, Control Authorities may 
authorize a lower minimum number of grab samples for pH, cyanide, total 
phenols, oil and grease, sulfides, and volatile organic compounds. Of 
course, where there has

[[Page 60159]]

been a change to existing facilities, for example, the addition of 
treatment, historic data that does not represent the current Discharge 
would not be able to be used to justify a lower minimum of grab 
samples.
    As stated previously, Control Authorities must ensure that 
compliance samples are taken with sufficient care to produce evidence 
admissible in enforcement proceedings or in judicial actions as 
required by 40 CFR 403.8(f)(2)(vii). To further strengthen this point, 
the following sentence, which the proposed rule would have deleted, is 
retained in 40 CFR 403.12(g)(3): ``The Control Authority shall require 
that frequency of monitoring necessary to assess and assure compliance 
by Industrial Users with applicable Pretreatment Standards and 
Requirements.'' Sampling and analysis techniques must yield analytical 
data that is representative of the Discharge. The Control Authority 
will still need to document how alternate sampling techniques are 
representative of the Discharge, and may require that more than four 
grab samples be taken and separately analyzed to ensure that sampling 
is representative. Where the Control Authority cannot verify that 
previous techniques were representative, such data will not support the 
use of this alternative practice. EPA notes that ``non-significant 
CIUs'' (discussed in Section III.K of the final rule) may be authorized 
to substitute annual certification for sampling and analysis. See 40 
CFR 403.12(q).
    Will EPA define ``representative'' sampling in the rule? Commenters 
noted that the rules repetitively use the concept of ``representative'' 
samples, but do not precisely define what the samples are supposed to 
represent. In the proposed rule preamble (64 FR 39582, July 22, 1999), 
EPA indicated that it would not offer a comprehensive definition of 
what constitutes a ``representative sample'' or specific guidance. EPA 
is not defining ``representative sample'' in the final rule. Guidance 
on the subject may be found in Industrial User Inspection and Sampling 
Manual for POTWs (EPA, 1994, http://www.epa.gov/npdes/pubs/owm0025.pdf).
    Sampling methods to yield a representative sample may vary 
depending on the site-specific situations of an individual discharger 
and the parameter that must be analyzed. Issues for the Control 
Authority to consider and document in prescribing sampling protocols 
include: (1) The appropriate sampling period (e.g., 24 hours or during 
the period of discharge); (2) use of flow proportional versus time-
proportional methods; (3) use of grab samples versus composite samples; 
(4) use of grab samples for pH monitoring; (5) use of grab samples for 
degradable and volatile parameters; (6) allowing manual compositing of 
samples when the methodology is approved by EPA; and (7) applying the 
criteria to instantaneous, daily maximum, and monthly average limits.
    Is EPA providing further clarifying language for collection of 
samples during process wastewater Discharges in the final rule? A 
commenter asked EPA to clarify whether a sample taken during a 24-hour 
period must be taken during a calendar day, or whether a sample may be 
taken over the course of two days. For example, if a facility 
discharges 24 hours per day, must the sample be taken from midnight to 
midnight, or may it be taken for other twenty-four hour periods (e.g., 
noon to noon)?
    EPA interprets a ``day'' to be a 24-hour period and does not 
require that it occur within a calendar day. This is consistent with 
the definition for ``daily discharge'' in the NPDES regulations at 40 
CFR 122.2. Daily discharge means the ``discharge of a pollutant'' 
measured during a calendar day or any 24-hour period that reasonably 
represents the calendar day for purposes of sampling. For pollutants 
with limitations expressed in units of mass, the ``daily discharge'' is 
calculated as the total mass of the pollutant discharged over the day. 
For pollutants with limitations expressed in other units of 
measurement, the ``daily discharge'' is calculated as the average 
measurement of the pollutant over the day. This is existing policy and 
was not proposed to be modified in the rule, and therefore has not been 
added to the final rule. EPA recognizes that Control Authorities may 
define a more specific sampling period.
    Another commenter asked for EPA to clarify whether a sample may be 
taken over the course of two calendar days in other circumstances. For 
example, if a facility discharges from 7 a.m. to 7 p.m., must a sample 
be taken from 7 a.m. to 7 p.m., or may a sample be taken from noon on 
one day to noon on the next day so long as only regulated wastewater is 
sampled? In the example provided, the sampling for compliance would 
need to be representative of the categorical process Discharge, and 
would need to account for other factors such as ensuring that stagnant 
water is not sampled if the facility is not discharging, and that 
process wastewater is not being discharged during the 7 p.m. to 7 a.m. 
period (for instance in an overtime situation). Where a sampler is 
placed from noon to noon, and wastewater samples (with volume 
proportionate to Discharge) are only collected during the discharge 
period (e.g., there is not a process wastewater Discharge, and no 
samples are collected from 7 p.m. to 7 a.m.), and the samples are 
properly preserved, then it is likely that the sample would be 
appropriate for use to determine compliance during a 24-hour period. 
Since this example addresses a site-specific situation, EPA is not 
inclined to revise the rule to address one particular set of 
circumstances. While other industries may have similar situations, the 
Control Authorities will need to consider all of the site-specific 
circumstances in detailing the sampling requirements for the facility 
in the individual Industrial User's control mechanism.
    A commenter expressed concern with the proposed language pertaining 
to required sampling periods. The section originally clearly pertained 
only to sampling required for reporting under subsections 40 CFR 
403.12(b), (d) and (e), of all categorical streams. As revised in the 
proposal, the requirements also apply to reports required under 
subsection (h) as well as to all other non-categorical waste streams. 
The commenter stated that the discussion in the preamble to the 
proposed rule seemed to indicate these very specific requirements only 
apply to categorically regulated wastestreams. However, the commenter 
indicated that this intent was not adequately stated in the regulation 
itself.
    The commenter went on to state, ``Local limits are developed based 
on total daily average influent loadings and total daily flows from all 
sources tributary to the receiving treatment plant. Many IUs, 
particularly larger ones, will have wastewater flows, from sources such 
as cooling systems, boilers, etc. that continue throughout the 24-hour 
day, as well as flows from maintenance and clean-up activities that 
often occur during non-process periods. In some cases, continuing 
composite sampling during these `off-process' periods may, in fact, 
reduce the daily average concentration of a pollutant. In other cases, 
pollutant Discharges during maintenance or clean-up activities, may 
contribute higher levels of pollutants than during normal processing 
periods. In either case, to determine compliance with local limits, it 
seems sampling should be conducted throughout the period of discharge, 
regardless of whether or not `process' operations are occurring the 
entire time.''

[[Page 60160]]

    In response, EPA removed the sentence from the proposed rule that 
read, ``For those Industrial User Discharges subject to categorical 
Pretreatment Standards that do not operate on a 24-hour per day 
schedule, the samples must be collected at equally spaced intervals 
during the period that process wastewater is being discharged.'' It 
would be too complicated to try to address all local limits variations 
in this section of the regulation, and as indicated by the commenter, 
the proposed language did not clarify the issue.

G. Significant Noncompliance Criteria (40 CFR 403.8(f)(2)(viii))

1. What were the rules in effect prior to today's rule?
How is ``Significant Noncompliance'' (SNC) currently defined?
    The previous 40 CFR 403.8(f)(2)(vii) defined ``Significant 
noncompliance'' (SNC), as it applies to Industrial Users to include 
violations that meet one or more of eight criteria. The criteria are: 
(1) Chronic violations of Discharge limits (where 66 percent or more of 
all measurements taken for the same pollutant parameter during a six-
month period exceed the daily maximum limit or the average limit); (2) 
Technical Review Criteria (TRC) violations (where 33 percent or more of 
all measurements taken for the same pollutant parameter during a six-
month period equal or exceed the product of the daily maximum limit or 
the average limit multiplied by the applicable TRC (TRC equals 1.4 for 
BOD, TSS, fats, oil and grease and 1.2 for all other pollutants except 
pH)); (3) any other violation of a Pretreatment effluent limit that the 
Control Authority determines has caused, alone or in combination with 
other Discharges, Interference or Pass Through; (4) any discharge of a 
pollutant that has caused imminent endangerment to human health, 
welfare or to the environment or has resulted in the POTW's exercise of 
its emergency authority to halt or prevent such a discharge; (5) 
failure to meet, within 90 days after the schedule date, a compliance 
schedule milestone contained in a local control mechanism or 
enforcement order for certain activities; (6) failure to provide 
required reports within 30 days after the due date; (7) failure to 
accurately report noncompliance; and (8) any other violation or group 
of violations which the Control Authority determines will adversely 
affect the operation or implementation of the local Pretreatment 
Program.
What are the background and purpose of the SNC criteria?
    On July 24, 1990, EPA modified 40 CFR 403.8(f)(2)(vii) to include 
the existing definition of SNC (55 FR 30082). The purpose of this 
modification was to provide some certainty and consistency among POTWs 
for publishing their lists of Industrial Users in significant 
noncompliance. EPA modeled the modification after the criteria under 
the NPDES program used to determine SNC violations for direct 
dischargers. By making the modifications, EPA also established more 
parity in tracking violations by direct and indirect dischargers.
What happens when an Industrial User facility is in SNC?
    POTWs are required to publish annually a list of Industrial Users 
in SNC at any time during the previous twelve months. In the previous 
rules, the POTW was required to publish this list in the largest daily 
newspaper published in the municipality in which the POTW is located.
    The Agency has emphasized that Industrial Users are liable for any 
violation of applicable Pretreatment Standards and Requirements, and 
has strongly encouraged Control Authorities to take some type of 
enforcement response for each such instance of noncompliance. 
Supporting this approach, EPA notes that the very underlying premise of 
the Enforcement Response Plan (40 CFR 403.8(f)(5)) is that there be 
some type of POTW response for each instance of noncompliance. 
Appropriate types of enforcement responses are addressed in the POTW's 
Enforcement Response Plan, although EPA guidance recommends that 
violations rising to the level of SNC be met with some type of formal 
enforcement action like an enforceable order (Guidance For Developing 
Control Authority Enforcement Response Plans, EPA 832-B-89-102, 
September 1989, (see http://www.epa.gov/npdes/pubs/owm0015.pdf.)
2. What changes did EPA propose?
    EPA proposed the following modifications to the SNC provision in 
1999:
a. Publication
    EPA proposed to amend the previous 40 CFR 403.8(f)(2)(vii) to allow 
publication of the SNC list in any paper of general circulation within 
the jurisdiction served by the POTW that provides meaningful public 
notice rather than in the largest daily newspaper published in the 
municipality as is currently required.
b. Applicability
    EPA proposed to amend the SNC criteria to apply only to Significant 
Industrial Users (SIUs). Under the existing regulations, SNC can apply 
to any Industrial User.
c. Daily Maximum or Average Limit Violations
    EPA proposed to amend the previous 40 CFR 403.8(f)(2)(vii)(A), (B), 
and (C) to include a broader set of violations than just daily maximum 
and average limits.
d. Other Issues
    EPA also took comment on several other issues, but did not propose 
specific changes. These issues include Technical Review Criteria (TRC), 
late reports, and rolling quarters.
3. What changes is EPA finalizing in today's rule?
    EPA is finalizing four changes to amend 40 CFR 403.8(f)(2)(vii).
a. Publication
    EPA is amending 40 CFR 403.8(f)(2)(vii) (now 40 CFR 
403.8(f)(2)(viii)) to allow publication of the SNC list in any paper of 
general circulation that provides meaningful public notice within the 
jurisdiction served by the POTW. EPA's intent in modifying this 
requirement is to be consistent with the July 17, 1997 amendments to 
Part 403 regarding modifying POTW Pretreatment Programs (62 FR 38406). 
Under the amended 40 CFR 403.11(b)(1)(i)(B), publication can be in any 
paper of general circulation within the jurisdiction served by the POTW 
that provides public notice. It is EPA's view that this new performance 
standard for publishing SNC violations properly balances the need to 
give the POTW the flexibility to choose an appropriate newspaper within 
its community, with the need to ensure effective public notice and 
deterrence of ``bad actors.''
b. Applicability
    EPA is amending the SNC criteria so that SNC will apply only to 
SIUs and to those Industrial Users that have caused Pass Through or 
Interference, have a Discharge that resulted in the POTW's exercise of 
its emergency authority to halt or prevent such a Discharge, have 
caused imminent endangerment to human health, welfare, or the 
environment, or have otherwise adversely affected the POTW's ability to 
operate its Pretreatment program. This approach is consistent with the 
NPDES

[[Page 60161]]

SNC policy which only applies to major dischargers. See ``Revision of 
NPDES Significant Noncompliance (SNC) Criteria to Address Violations of 
Non-Monthly Average Limits,'' memorandum from Steven A. Herman, 
Assistant Administrator for the Office of Enforcement and Compliance 
Assurance, September 21, 1995. Additionally, EPA emphasizes that the 
SNC criteria apply not only to SIUs, but also to IUs that cause 
significant adverse impacts to the POTW, human health or the 
environment. These modifications should cut down on administrative 
burdens and allow better resource targeting. These modifications ensure 
the POTW's ability to address all potentially problematic Users 
adequately. The Agency wants to make it clear that this change is 
focused only on the POTW's publication and reporting requirements. EPA 
fully expects POTWs to take appropriate enforcement actions against any 
Industrial User that violates a Pretreatment Standard or requirement. 
POTWs still have the option of publishing non-significant Industrial 
Users with violations that do not fall within one of the above-
mentioned categories.
c. Daily Maximum or Average Limitations
    EPA is amending 40 CFR 403.8(f)(2)(vii)(A) and (B) (now 40 CFR 
403.8(f)(2)(viii)(A) and (B)) to apply to a broader range of violations 
such as other numeric limits, instantaneous limits, narrative limits, 
or operational standards, and amending 40 CFR 403.8(f)(2)(vii)(C) (now 
40 CFR 403.8(f)(2)(viii)(C)) to address other Pretreatment Standards 
and requirements. This change is important since some local limits may 
be expressed as instantaneous limits or narrative limits. The revised 
language addresses other types of requirements like operational 
standards. The amendment is generally consistent with EPA's revision to 
its NPDES SNC policy where EPA broadened the criteria to address non-
monthly average limitations. See ``Revision of NPDES Significant 
Noncompliance (SNC) Criteria to Address Violations of Non-Monthly 
Average Limits,'' memorandum from Steven A. Herman, Assistant 
Administrator for the Office of Enforcement and Compliance Assurance, 
September 21, 1995.
d. Late Reports
    EPA is amending 40 CFR 403.8(f)(2)(vii)(F) (now 40 CFR 
403.8(f)(2)(viii)(F)) so that SNC applies to reports that are provided 
more than 45 days after the due date, instead of to reports that are 30 
days late. The change applies to required reports such as baseline 
monitoring reports, 90-day compliance reports, periodic self-monitoring 
reports, and reports on compliance with compliance schedules. EPA is 
making this change because many Control Authorities and Industrial 
Users that commented on the late report issue argued that the 30-day 
timeframe was too restrictive. EPA notes that Industrial Users that 
submit reports even one day late are in violation.
4. What significant changes were made to the proposed rule?
a. Applicability
    EPA modified the proposal by adding to the scope of SNC those non-
significant IUs that cause Pass Through or Interference, have a 
Discharge that resulted in the POTW's exercise of its emergency 
authority to halt or prevent such a Discharge, cause imminent 
endangerment to human health, welfare, or the environment, or otherwise 
adversely affect the POTW's ability to operate its Pretreatment 
program.
b. Daily Maximum or Average Limit Violations
    In the proposal, EPA proposed to modify the provisions of the then 
current 40 CFR 403.8(f)(2)(vii)(A), (B) and (C) (now 40 CFR 
403.8(f)(2)(viii)(A), (B) and (C)) to address not only violations of 
daily maximum or longer-term average limits, but also a broader range 
of violations such as other numeric limits, instantaneous limits, 
narrative limits, or operational Standards. EPA has modified the 
proposal in the following ways:
    Chronic violations (40 CFR 403.8(f)(2)(viii)(A): EPA has clarified 
the revised language to more accurately describe the target violations. 
The term ``numeric'' was added to clarify that only Standards or 
Requirements that can be numerically quantified can be examined for 
possible chronic violations. Also, EPA specifies that chronic 
violations include violations of both ``Standards and Requirements'; 
the term ``Requirements'' was not included in the proposal. The 
inclusion of this term provides the intended broader scope that EPA 
sought in the proposal. EPA also clarifies that violations of 
instantaneous limits are also to be considered for chronic violations.
    During the process of revising the chronic and TRC violations 
provision, EPA found the difference between the use of the phrase ``for 
the same pollutant parameter'' for chronic violations, and the phrase 
``for each pollutant parameter'' for TRC violations, may have led to 
some unintended misinterpretation. It is EPA's intention that the 
chronic and TRC criteria be applied to the ``same pollutant 
parameter.'' To avoid potential confusion, EPA modified both the 
chronic and TRC provisions to use the same phrase (i.e., for the same 
pollutant parameter), and to place the phrase in the most appropriate 
place in the provision to improve its clarity.
    TRC (40 CFR 403.8(f)(2)(viii)(B): EPA adopted the same changes for 
TRC violations that were made for chronic violations.
    Any other violations: EPA has modified the proposed rule by 
including clarifying language on what is meant by a ``Pretreatment 
Standard or Requirement.'' EPA provides parenthetical examples, 
including daily maximum, long-term average, instantaneous, or narrative 
Standards.
c. Late Reports
    EPA did not propose any changes to the then current 40 CFR 
403.8(f)(2)(vii)(F) (now 40 CFR 403.8(f)(2)(viii)(F)), which contains 
the SNC criterion for late reports. Instead, EPA sought comments on 
several options for the late report criterion. The options included 
tying SNC to a pattern of late reporting; applying the SNC criterion to 
a late report only if the report indicated that a violation of 
monitoring requirements or numeric limitations had occurred; allowing 
POTWs to extend ``waivers'' in some circumstances to Industrial Users 
that offered a satisfactory reason why reports were late; limiting the 
types of reports to which the SNC criterion applies; retaining the 30-
day late report criterion, but changing the publication requirement as 
it pertains to late reports; extending the time after which a late 
report puts an Industrial User in SNC (e.g., to 45 days or 60 days); or 
providing the POTW with complete authority for determining when late 
reports trigger SNC. EPA is amending the criterion so that Industrial 
Users are in SNC if reports are not provided within 45 days after their 
due date.
5. Summary of Major Comments and EPA Response
a. Publication
    Most commenters were in favor of making the change that EPA is 
adopting in today's rule. EPA is amending the regulation to allow 
publication of the SNC list in any paper of general circulation that 
provides meaningful public notice within the jurisdiction served by the 
POTW. One reason given

[[Page 60162]]

for supporting this change included possible lower costs to the 
municipality. Other commenters pointed out that the previous use of the 
largest daily newspaper requirement did not make sense in certain 
situations. Such examples included that the largest daily newspaper may 
not always have provided the most effective notice, and the fact that 
some municipalities may only have a weekly publication and no daily 
publication.
    EPA also sought comment on an appropriate definition for 
``meaningful public notice'' to ensure some level of consistency across 
the Pretreatment programs. Some commenters provided suggestions for 
defining ``meaningful public notice'' such as linking it to the service 
area population, the circulation rate of the newspaper, or the official 
daily newspaper as determined by the Control Authority. Other 
commenters stated that the definition of ``meaningful public notice'' 
should be determined by the Control Authority because defining it by 
service population or circulation rate could be overly burdensome and 
not necessarily meet the intent of the Standard. EPA agrees with the 
commenters who suggested that defining ``meaningful public notice'' 
could be overly burdensome. Therefore, at this time, EPA has decided 
not to define ``meaningful public notice.''
b. Applicability
    The majority of commenters supported either modifying the 
application of SNC to SIUs only, or to SIUs and those Industrial Users 
which caused Pass Through or Interference, had a Discharge that 
resulted in the POTW's exercise of its emergency authority to halt or 
prevent such a Discharge, caused imminent endangerment to human health, 
welfare, or the environment, or otherwise adversely affected the POTW's 
ability to operate its Pretreatment program. Some commenters did not 
want to limit SNC to apply only to SIUs because not all Industrial 
Users which should be are properly identified as SIUs. The commenters 
also noted that all Industrial Users are required to comply with 
Pretreatment Standards and Requirements, regardless of whether they are 
designated as SIUs. (Several commenters also indicated that changing 
the SNC definition to apply only to SIUs would be unfair, because, with 
such a change, this definition would no longer apply to other 
Industrial Users that could cause the same types of impacts as SIUs.) 
EPA agrees that certain non-Significant Industrial Users should 
continue to be covered under the SNC provisions. By including the 
application of SNC to SIUs and those Industrial Users which cause the 
specific problems referenced above, the rule should address the 
commenters' concerns.
    The distinction EPA is making today is not focused on the size of 
the facility; rather, EPA focuses on those dischargers with the largest 
potential to impact the system. EPA continues to strongly encourage 
POTWs to use their existing authority under what will now be codified 
as 40 CFR 403.3(v) to designate any Industrial Users as significant if 
they have the reasonable potential to adversely affect the POTW's 
operation or to violate any Pretreatment Standard or Requirement. This 
includes considering smaller facilities that have the potential (either 
individually or collectively) to impact the system. Furthermore, all 
Industrial Users are required to comply with Pretreatment Standards and 
Requirements, regardless of whether they are designated as SIUs, and 
EPA expects appropriate enforcement to be taken for each violation by 
any Industrial User.
c. Daily Maximum or Average Limit Violations
    Commenters were divided on this proposed rule language. One 
commenter mentioned that the revision would be much more consistent 
nationally if it were to apply only to numeric categorical Pretreatment 
Standards. Another commenter indicated that the Control Authorities 
often are required to make ``subjective judgments regarding compliance 
with narrative Standards, instantaneous limits and some general 
prohibitions,'' and that such a subjective judgment would be an 
inappropriate basis for an SNC determination. Another commenter 
indicated that all applicable Pretreatment Standards are enforced now, 
and that there would be no discernible benefit to expanding the types 
of violations that could trigger a SNC determination. Some commenters 
cited the possible increased burden on the Control Authorities if such 
additional Standards were used to make SNC determinations.
    On the other hand, several commenters were supportive of the 
proposed rule change. Some commenters indicated that the revision would 
better reflect the fact that Industrial Users must be in compliance 
with all applicable Pretreatment Standards and requirements in order to 
meet the goals of the national Pretreatment program. Other commenters 
focused on the fact that Interference or pass-through could be caused 
by violations of Standards other than categorical Pretreatment 
Standards, and therefore they saw a need to expand the SNC criteria.
    EPA agrees with those commenters who supported an expansion of the 
range of SNC criteria consistent with the proposed rule, and has added 
other numeric limits, instantaneous limits, narrative Standards, or 
operational Standards as part of the SNC criteria. This approach will 
give more equal weight to categorical Standards, local limits, and 
other Standards as applicable Pretreatment Standards and Requirements. 
This expansion of SNC criteria would also potentially enhance the 
Control Authority's ability to address such violations (i.e., other 
numeric limits, instantaneous limits, narrative Standards, or 
operational Standards) by placing a higher priority on these 
violations. EPA has concluded that such a change would still provide 
national consistency and be more protective by better ensuring 
compliance with all applicable Pretreatment Standards and Requirements. 
Control Authorities are currently expected to address violations of all 
applicable Pretreatment Standards and Requirements, so that this 
proposal should not necessarily impose any increased enforcement 
responsibilities on the Control Authorities. In addition, as the 
preamble to the proposed rule states (64 FR 39593), this approach would 
be consistent with ``EPA's recent revision to its NPDES SNC policy 
where EPA broadened the criteria to address non-monthly average limit 
violations.'' See ``Revision of NPDES Significant Noncompliance (SNC) 
Criteria to Address Violations of Non-Monthly Average Limits,'' 
memorandum from Steven A. Herman, Assistant Administrator for the 
Office of Enforcement and Compliance Assurance, September 21, 1995.
    Under the NPDES SNC policy, when a parameter has both a monthly 
average and a non-monthly average limit, a facility is only considered 
in SNC for the non-monthly average if the monthly average is also 
violated to some degree (but less than SNC). EPA sought comment on 
whether such a caveat is also appropriate for the Pretreatment 
Regulations. Very few commenters focused on this particular topic. A 
few commenters indicated that a determination that a particular 
violation or set of violations constituted SNC should only occur if 
there was a meaningful violation of the POTW's NPDES Permit limit for 
that particular parameter. In the absence of significant comment and in 
recognition that effluent violations other than monthly average 
violations could have significant impacts on the POTWs, EPA

[[Page 60163]]

has decided not to modify the regulations to restrict SNC for 
violations of non-monthly averages.
d. Technical Review Criteria (TRC)
    In the existing regulations, the Technical Review Criteria (TRC) 
may be found at 40 CFR 403.8(f)(2)(vii)(B) (now found at 40 CFR 
403.8(f)(2)(viii)(B)). As described in the preamble to the proposed 
rule (64 FR 39593), these TRC ``* * * are numeric thresholds used to 
define a subcategory of SNC * * * based on the magnitude of an effluent 
violation. A TRC violation occurs where 33 percent or more of all of 
the measurements for each pollutant parameter taken during a six-month 
period equal or exceed the product of the daily maximum limit or the 
average limit multiplied by the applicable TRC.'' TRC is equal to 1.4 
times the applicable Standard for BOD, TSS, fats, oils and grease; TRC 
is also equal to 1.2 times the applicable Standard for all other 
pollutants except pH.
    As further stated in the preamble to the proposed rule (64 FR 
39593), EPA was not proposing to amend the TRC. However, EPA did seek 
comment on this topic, particularly regarding local limits. EPA stated 
that it was ``* * * interested in suggestions for workable alternatives 
* * * that would ensure that the magnitude of a violation * * *'' 
continues to be part of the definition of SNC, with the condition that 
such alternatives ``* * * would not unduly increase the workload on 
either the Control Authority or the Approval Authority.'' Based on its 
review of the comments, EPA is not considering any further changes to 
TRC.
    Several commenters expressed a clear preference that TRC not be 
modified. Several commenters also provided alternative numeric 
thresholds for TRC. However, there was no consensus among the comments 
for an alternate threshold and a sufficient justification for the use 
of such alternative thresholds was not provided. As explained in the 
preamble to the proposed rule (64 FR 39593), the existing regulations 
are ``consistent with the NPDES approach which has generally been 
accepted over the years as an indicator of a `significant' level of 
exceedance which should be reviewed for enforcement purposes.'' 
Furthermore, as that same preamble stated, ``(T)he same considerations 
apply to the TRC as it is applied to categorical Standards in the 
Pretreatment program and may be relevant for local limits.'' In a 
sense, by keeping the TRC the same for both direct dischargers to 
surface waters and indirect dischargers to POTWs, the criteria help 
maintain a ``level playing field'' by ensuring that this subcategory of 
SNC is linked to some nationally-consistent designated magnitude above 
the applicable Standard, whether that Standard is an NPDES Permit 
effluent limit, a categorical Pretreatment Standard, or a local limit.
    Several commenters, using similar language, stated that ``it is 
incumbent on EPA to develop TRC that are germane to the objectives of 
the Pretreatment program, developed in a manner that lends credence to 
application of effluent guidelines and local limits, and are 
technically sound and defensible.'' Just as best achievable technology 
Standards (BAT) and stream use are factors considered in the 
development of effluent limits, BAT and protection of the POTW's 
operations are factors considered in the establishment of categorical 
Pretreatment Standards and local limits respectively. Therefore, if 
these Pretreatment limits are properly derived for their intended 
purpose, the TRC are simply intended to represent numeric thresholds at 
magnitudes above these applicable Standards such that, above this 
level, such significant non-compliance should make the authority 
sufficiently concerned and warrant appropriate action. As such, EPA 
concludes that there is not sufficient reason to try to account only 
for instances of potential Pass Through or Interference, or to make 
allowances for the range of treatment plant performance, or to have 
different TRC for individual pollutant parameters for different POTWs. 
Such revisions would be contrary to EPA's intent to keep the 
regulations simple to understand and implement, and to not unduly 
increase the workload on the Control Authority or Approval Authority.
    Some of the commenters advocated the elimination of the TRC 
entirely. EPA disagrees with these commenters. As indicated above, EPA 
asserts that a measure of the magnitude of the violation is an 
appropriate consideration in determining SNC. The preamble to the 
proposed rule (64 FR 39593) stated that EPA was not proposing to amend 
the TRC, and EPA believes that radical revisions to the TRC are not 
warranted.
    One commenter indicated that TRC should only apply if the levels 
are at least five times the applicable Standard. EPA concludes that 
this level is far too high a threshold to serve as a proper deterrent 
to dischargers and as an adequate indicator of potential compliance 
problems. EPA emphasizes that POTWs should be concerned about reported 
results, the adequacy of industrial treatment, and potential impacts on 
the plant operations or receiving waters at levels which are much less 
than five times the applicable Standard.
    Some commenters sought to adjust the TRC by having them only apply 
to daily maximum limitations. Other commenters suggested that for the 
violations to rise to the level of SNC EPA modify the percentages for 
TRC and chronic criteria from 33 to 34% and from 66 to 67% of all 
measurements taken, respectively. EPA disagrees with these commenters, 
because it is not clear how these changes will improve the application 
of TRC or provide equal if not added environmental protection when 
compared to the existing TRC criteria.
    As stated above and in the preamble to the proposed rule (64 FR 
39593), EPA did seek comment on the TRC, particularly regarding local 
limits. No commenters focused on whether TRC may be inappropriate for 
local limits, based upon a distinction in the derivation, site-specific 
variability and intent of local limits as compared to categorical 
Pretreatment Standards. Therefore, EPA did not adopt changes to reflect 
the use of TRC for local limits.
e. Late Reports
    The existing regulations require that Industrial Users that 
submitted reports more than 30 days late be considered in SNC. This is 
consistent with the NPDES SNC approach for late reports. EPA did not 
propose any specific changes to this part of the SNC definition, but 
did solicit comment on possible options or combinations of options to 
modify this portion of the definition. The options included tying SNC 
to a pattern of late reporting; applying the SNC criterion to a late 
report only if the report indicated that a violation of monitoring 
requirements or numeric limitations had occurred; allowing POTWs to 
extend ``waivers'' in some circumstances to Industrial Users that 
offered a satisfactory reason why reports were late; limiting the types 
of reports to which the SNC criterion applies; retaining the 30-day 
late report criterion, but changing the publication requirement as it 
pertains to late reports; extending the time after which a late report 
puts an Industrial User in SNC (e.g., to 45 days or 60 days); or 
providing POTWs with complete flexibility for determining when late 
reports trigger SNC.
    Comments on this issue were mixed. Many commenters noted that 
reporting is important in and of itself and it serves a vital role in 
ensuring adequate implementation and oversight of the Pretreatment 
program. Commenters

[[Page 60164]]

noted that failure to submit or late submittal of reports impede POTWs 
from meeting goals of their approved programs. Because of the 
importance of reporting, a few commenters (POTWs) argued that EPA 
should retain the existing SNC criterion for late reports.
    However, a majority of commenters asked EPA to modify the SNC 
criterion for late reports in some way. They noted that reports are 
sometimes late because of circumstances that are beyond the control of 
the Industrial Users. Commenters also stated that publication should be 
reserved to Industrial Users that violate numeric Pretreatment 
Standards or fail to monitor, rather than for violations that some 
commenters characterized as ``administrative'' violations. One 
commenter also noted that a 30-day criterion may be appropriate for 
NPDES permittees, but not for the Pretreatment Program because NPDES 
permittees generally submit reports more frequently than Industrial 
Users regulated by the Pretreatment Program and because the 
Pretreatment Program also relies on surveillance by the POTWs. Based on 
these comments, EPA agrees that modifications to the SNC criterion for 
late reports are appropriate.
    Although most commenters favored modifications to the SNC criterion 
for late reports, commenters disagreed on how the provision should be 
modified. Some commenters stated that POTWs should be given complete 
flexibility in determining whether late reports constitute SNC. Others 
argued that POTWs should be provided some amount of flexibility, but 
not total flexibility. It is EPA's position that the definition of SNC 
should be consistent throughout the Pretreatment Program. Therefore, 
the Agency has chosen to establish a consistent SNC criterion for late 
reports that would avoid the use of different SNC criterion by various 
POTWs for the same type of reporting violations.
    Some commenters suggested that the SNC criterion for late reports 
should recognize a pattern of late reporting, or should consider the 
Industrial User's compliance history. For example, some commenters 
suggested that a late reporter be considered in SNC if 33 percent or 
more of required reports in a specified reporting period are provided 
more than 30 days late. Another commenter suggested that three 
monitoring reports submitted more than thirty days late could 
constitute a history of chronic late reports, and another commenter 
suggested that failure to submit a completed discharge monitoring 
report in any two months of any consecutive six month period should 
trigger SNC. EPA agrees that POTWs should take steps to address 
Industrial Users that demonstrate a pattern of late reporting. In 
addition, EPA strongly asserts that the SNC criterion for late reports 
must address reports that are submitted extremely late or that are 
never submitted, even if the extremely late submittal or failure to 
submit is a one-time occurrence.
    Some commenters argued that SNC for late reports should apply only 
if the report, once submitted, indicates that the Industrial User has 
violated a numeric Pretreatment Standard or failed to monitor. Others 
supported a provision in which reports provided more than 30 days late, 
but less than 45 days, should trigger SNC only if they indicated 
another violation. EPA views this suggested change as potentially 
minimizing the importance of reporting as a tool for POTWs to implement 
local Pretreatment Programs. Also, EPA asserts that the SNC criterion 
for late reports must address reports that are submitted extremely late 
or that are never submitted, even if the extremely late submittal or 
failure to submit is a one-time occurrence and even if the report does 
not indicate monitoring or effluent violations.
    A number of commenters supported extending the number of days until 
which late reports trigger SNC from 30 days to 45 days. EPA agrees that 
this change is appropriate and easy to implement. A few commenters 
suggested the option of extending the period from 30 days to 60 days. 
EPA has concluded that this change is not appropriate because most 
cases of late laboratory reports or other miscommunications can be 
addressed quickly. EPA also concludes that receiving data 60 days late 
would be more likely to jeopardize POTWs' management of their 
Pretreatment Programs and have the potential to adversely impact the 
POTW and its receiving water.
    A few commenters suggested that the SNC criterion for late reports 
should only apply to periodic self-monitoring reports and 90-day self 
compliance reports. EPA asserts that, in order to avoid confusion and 
ease tracking of late reports, the same criterion should be applied to 
all reports. One commenter asked that EPA amend the regulations so that 
SNC for late reports applies to ``baseline monitoring reports, 90-day 
compliance reports, periodic self-monitoring reports, or reports on 
compliance with compliance schedules'' (rather than ``baseline 
monitoring reports, 90-day compliance reports, periodic self-monitoring 
reports, and reports on compliance with compliance schedules''). The 
commenter was concerned that the provision could be interpreted to 
imply that Industrial Users must submit both the 90-day compliance 
reports and the periodic self-monitoring reports to avoid being in SNC. 
The list of reports comprises a list of examples of ``compliance 
reports.'' EPA does not agree that changes are needed to this language, 
nor does the Agency find the commenter's arguments to be valid.
    In considering revisions to the late reporting criterion for SNC, 
EPA notes that implementation of the Pretreatment Program relies 
heavily on a self-policing and self-reporting system. This self-
reporting is important to enforcement. If a failure to report becomes 
routine, the entire program can be weakened. EPA expects POTWs to take 
some level of enforcement action against any Industrial User that 
provides late reports. EPA would also like to emphasize that there is 
current flexibility in the existing rule to address some of the 
concerns related to one late report putting an Industrial User in SNC. 
For example, the Control Authority has some flexibility in setting the 
due date and can set it to coincide with some other established 
reporting or billing cycle. Also, in the enforcement response policy 
the POTW can have an escalation policy, whereby, for example, the 
Industrial User would receive a warning letter that the report is 5-10 
days late past the due date and/or fines associated with the report 
before it rises to the level of being in SNC.
f. Rolling Quarters
    EPA memoranda circa 1991 and 1992 form the basis of EPA's policy 
that SNC for IUs should be calculated on a rolling quarter basis. 
(September 9, 1991 memorandum from Michael B. Cook, Director of EPA's 
Office of Wastewater Enforcement and Compliance to Water Management 
Division Directors, Regions I-X and approved Pretreatment State 
coordinators, ``Application and Use of the Regulatory Definition of 
Significant Noncompliance for Industrial Users,'' http://www.epa.gov/npdes/pubs/application_use_regulatory.pdf, and January 17, 1992 
memorandum from Mark B. Charles, Chief of RCRA and Pretreatment 
Enforcement Section, to the Regional Pretreatment Coordinators, Regions 
I-X, ``Determining Industrial User Significant Noncompliance--One Page 
Summary,'' http://www.epa.gov/npdes/pubs/industrial_user.pdf). The 
term ``rolling quarters,'' under EPA's national policy, refers to an 
approach which requires the Control Authority to evaluate an Industrial 
User's compliance status at the end of each

[[Page 60165]]

quarter by using data from the previous six-month period. In the 
regulations, determinations of significant noncompliance are based upon 
six-month periods (40 CFR 403.8(f)(2)(viii)(A) and (B)).
    Many commenters expressed concern regarding the concept of rolling 
quarters and instead endorsed the adoption of static six-month periods 
that do not overlap. Many commenters were concerned that the use of 
rolling quarters could result in the need to publish the name of the 
Industrial User in two separate years for SNC for the same violation.
    Many commenters who supported the static six-month approach voiced 
concerns that the use of rolling quarters unnecessarily complicated the 
calculations of SNC and the annual publication of those IUs in SNC, 
without apparent benefits over the use of static six-month periods. 
They indicated that the concept was complex, difficult to implement and 
would only result in confusion for the Industrial Users and increased 
burden for the control authorities.
    Some commenters preferred to begin to ``roll'' time periods after a 
violation occurs, thus giving, as one commenter stated, the possibility 
to ``* * * allow Industrial Users to achieve compliance and obtain 
additional samples'' to verify compliance, all within the given time 
period. The commenters explained that this could give Industrial Users 
an opportunity to demonstrate compliance rather than being listed as 
being in SNC for violations that were corrected months ago. EPA noted 
in the preamble to the proposed rule (64 FR 39594, July 22, 1999) that 
while the Agency provided some discussion of the various opinions 
regarding the use of rolling quarters, EPA did not ultimately propose a 
specific change regarding rolling quarters national policy, did not 
seek comment on whether to discontinue EPA's national policy regarding 
the use of rolling quarters, and did not propose an alternative 
approach. It remains EPA's intention to continue the existing national 
policy that SNC for Industrial Users be evaluated on a rolling quarter 
basis. This approach, which is the same as the one used in the NPDES 
program for the determination of SNC by direct dischargers, will remain 
the same.
    EPA did seek comment on whether the concept of rolling quarters 
should be codified in the Pretreatment Regulations. Some commenters 
expressed their opposition to such codification, based largely upon 
their preference to use an alternative to rolling quarters. A few 
commenters supported codification, indicating that by making the use of 
the rolling quarters approach mandatory, EPA would help ensure national 
consistency in its use by Control Authorities. One commenter 
recommended codification of the due date for the annual publication of 
Industrial Users in SNC. After considerable internal discussion and 
careful deliberation, EPA has decided not to codify rolling quarters in 
the Pretreatment Regulations.
    In the preamble to the proposed rule (64 FR 39594, July 22, 1999), 
EPA specifically sought comment on whether the regulations should be 
revised to allow Control Authorities to waive the second publication 
(as described above) ``where that second publication is based solely on 
the violations occurring in the last quarter of the previous 
Pretreatment year.'' Many commenters sought the elimination of this 
double publication issue through a specific rule change to the 
publication requirements, particularly if the final rule implements the 
concept of rolling quarters. Those commenters indicated that such 
duplicate publications in the newspaper would be unfair to the 
Industrial User which had corrected its compliance problems and would 
mislead the public regarding the status of such an Industrial User.
    EPA's 1991 memorandum, cited previously, addressed the issue of 
possible publication in two different years of an Industrial User that 
is in SNC for the same violation. EPA was clear on the point that 
double publication is not intended by the use of rolling quarters. It 
stated that ``(I)f a facility has been determined to be in SNC based 
solely on violations which occurred in the first quarter of the 15-
month evaluation period (i.e., the last quarter of the previous 
Pretreatment year) and the facility has demonstrated consistent 
compliance in the subsequent four quarters, then the POTW is not 
required to republish the Industrial User (IU) in the newspaper if the 
IU was published in the previous year for the same violations.'' It is 
EPA's position that no revisions are needed on this point. However, EPA 
wishes to clarify that a facility does not need to have full compliance 
to avoid double publication. Rather, if a facility was already 
determined to be in SNC during the previous pretreatment year, and the 
facility would not be in SNC in the current year but for violations 
occurring during the last three months of the previous year, then the 
facility is not considered in SNC for the current year.

H. Removal Credits--Compensation for Overflows (40 CFR 403.7(h))

1. General Background
    Section 307(b) of the CWA which requires EPA to establish 
pretreatment standards also authorizes a discretionary program for 
POTWs to grant ``removal credits'' to their industrial users. The 
credit in the form of a less stringent categorical Pretreatment 
Standard would allow an Industrial User to discharge a greater quantity 
of a pollutant than would otherwise be authorized because the POTW's 
treatment processes sufficiently reduce the concentrations of the 
pollutant.
    Section 307(b)(1) establishes a three-part test that a POTW must 
meet in order to obtain removal credit authority for a given pollutant. 
Removal credits may be authorized only if (1) the POTW ``removes all or 
any part of such toxic pollutant,'' (2) the POTW's ultimate discharge 
would ``not violate that effluent limitation or standard which would be 
applicable to that toxic pollutant if it were discharged'' directly 
rather than through a POTW, and (3) the POTW's discharge would ``not 
prevent sludge use and disposal by such [POTW] in accordance with 
section [405] * * *'' (Sec. 307(b)). EPA promulgated removal credit 
regulations that are codified at 40 CFR 403.7 (See 43 FR 27736, 46 FR 
9404, 49 FR 31212, and 52 FR 42434).
    In this rulemaking, EPA proposed only one limited change to the 
removal credits provision of the General Pretreatment Regulations. A 
number of commenters, however, asked EPA to consider changes to the 
regulations to allow greater availability of removal credits for a 
broader range of pollutants. The Agency's current plans with respect to 
sewage sludge regulations and removal credits are discussed in detail 
in a Notice published today with this rule.
2. What are the existing rules governing how removal credit authority 
is affected by the occurrence of overflows in the POTW sewer system?
    Section 403.7 of the General Pretreatment Regulations describes the 
conditions under which removal credits may be available to an 
Industrial User. Among other things, the regulation provides that, 
given certain conditions are met, a POTW may grant a removal credit to 
an Industrial User equal to or less than its consistent removal rate 
for that pollutant. The regulation defines ``consistent removal rate.'' 
In circumstances where a POTW ``annually Overflows'' untreated 
wastewater to

[[Page 60166]]

receiving water, the POTW may claim consistent removal of the pollutant 
only under the conditions specified either in 40 CFR 403.7(h)(1) or 
(2). ``Overflow'' means the intentional or unintentional diversion of 
flow from the POTW before the POTW treatment plant.
    Under subsection (h)(1), a POTW may claim consistent removal only 
if, for example, the POTW has established plans for notifying 
Industrial Users in the event of a potential overflow and the 
Industrial User has, among other things, taken certain actions to 
provide containment of, or ceases or reduces, its discharges of the 
pollutant for which the removal credit is sought. Alternatively, in 
subsection (h)(2), the current rule provides that consistent removal 
may be claimed under a mathematical formula that reduces consistent 
removal to take account of the Overflows so long as the POTW has taken 
steps required by an EPA guidance document on combined sewer overflows 
(CSOs) published on December 16, 1975 (i.e., PRM 75-34). This latter 
requirement was intended to ensure that POTWs granting removal credits 
were taking appropriate steps to address CSOs as outlined in EPA's 
then-current guidance. Since then, EPA has adopted the CSO Control 
Policy with updated requirements for addressing CSOs. Section 402(q) of 
the CWA provides that all NPDES permits must be consistent with the CSO 
Control Policy.
3. What changes did EPA propose?
    EPA proposed to make Industrial Users that are upstream of 
Overflows ineligible for removal credits unless they could establish 
that their discharges would be consistently treated. Consistent with 
that approach, the proposal would have deleted the existing provision 
in 40 CFR 403.7(h)(2) which allows removal credits for discharges that 
are subject to Overflows, but reduces the credit by a percentage equal 
to the percentage of time in a year that the POTW is subject to 
Overflows. In addition, references in the regulation to the now 
obsolete guidance on construction grants review procedures for 
developing CSO control were to be removed by deleting Appendix A as 
well as discussion of that guidance in 40 CFR 403.7(h)(2).
4. What changes is EPA finalizing in today's rule?
    Today, EPA is limiting its action to updating the references to 
obsolete guidance published in 1975, for the construction grants 
program. Existing 40 CFR 403.7(h)(2)(ii) and (iii) and Appendix A are 
deleted and replaced with a requirement for the POTW to be in 
compliance with all NPDES permit requirements and other requirements in 
any orders or decrees issued pursuant to the 1994 CSO Control Policy. 
As noted above, CWA 40 CFR402(q) requires all NPDES permits to conform 
to this policy. The existing formula in 40 CFR 403.7(h)(2)(i) for 
adjusting removal credits based on the number of hours of Overflow 
discharges occurring in a year is retained.
    EPA decided not to adopt the proposed revision which would have 
required that removal credits be limited to the percentage of the 
pollutant that was removed during the Overflow event. EPA does not have 
sufficient information to determine the impacts of such a change on 
existing programs using removal credits and is concerned that the 
adoption of this change may have disrupted these programs with little 
environmental benefit.
    Today's rule also makes one technical correction in response to 
comments received. EPA corrects footnote 1 in Appendix G, Table I 
(Regulated Pollutants in Part 503 Eligible for a Removal Credit) by 
including a reference to the use of carbon monoxide. The Part 503 
regulations now allow the use of either total hydrocarbon (THC) or 
carbon monoxide concentrations to represent organic compounds in exit 
gas from incinerators. EPA amended Part 503 subpart E (59 FR 9095, 
February 25, 1994) to authorize the demonstration of compliance with 
the 100 ppm THC operational standard by meeting a 100 ppm CO limit. 
Therefore, EPA is modifying footnote 1 to reflect the fact that either 
total hydrocarbon or carbon monoxide, as a surrogate monitoring 
parameter, may be used.

I. Miscellaneous Changes (40 CFR 403.12(g), (j), (l), and (m))

Signatory Requirements for Industrial User Reports and POTW Reports (40 
CFR 403.12(l) and (m))
    Today's rule revises the signatory requirements for Industrial 
Users at 40 CFR 403.12(l)(1)(ii) to adopt more flexible standards for 
determining who must sign reports on behalf of a corporation. EPA's 
NPDES regulations include similar requirements for NPDES Permits. See 
40 CFR 122.22(a)(1)(ii). Today's amendments make similar changes to the 
signatory requirements for ``duly authorized employees'' of POTWs. See 
40 CFR 403.12(m) and 122.22(a).
1. What were the rules in place prior to today's rulemaking?
    Sections 403.12(l)(1)(ii) previously limited the circumstances in 
which a plant manager could sign a Pretreatment report as a responsible 
corporate officer. Prior to today's rule, in order to sign a report on 
behalf of a company, the manager was required to manage a facility with 
more than 250 employees or $25 million in sales or expenditures.
    Section 403.12(i) addresses annual reporting requirements for 
POTWs. Prior to today's rule, 40 CFR 403.12(m) required these reports 
to be signed by ``a principal executive officer, ranking elected 
official or other duly authorized employee if such employee is 
responsible for overall operation of the POTW.' ''
2. What changes did EPA propose?
    EPA proposed to revise the signatory requirements for Industrial 
Users at 40 CFR 403.12(l)(1)(ii) to adopt the same language that EPA 
proposed in 1996 (61 FR 65268) and now uses for direct dischargers at 
40 CFR 122.22(a)(1)(ii). On May 15, 2000, EPA finalized revisions to 40 
CFR 122.22(a)(1)(ii) to replace the numeric criteria for designating an 
appropriate signer with more flexible narrative criteria (64 FR 39595). 
Rather than conditioning signature authority on resource management 
size, the revised criteria describe the necessary signer in terms of 
general management authority and responsibilities. The revised criteria 
require the manager to have the authority to make capital investment 
decisions and assure long term environmental compliance.
    In addition, EPA also proposed to revise the signatory requirements 
for POTW reports at 40 CFR 403.12(m) so the requirement would be more 
consistent with signatory requirements in the current 40 CFR 122.22(a). 
EPA proposed to allow signature by a duly authorized employee having 
responsibility for the overall operation of the facility or activity 
such as the position of POTW Director, Plant Manager, or Pretreatment 
Program Manager. This authorization could be made in writing by the 
principal executive officer or ranking elected official, and submitted 
to the Approval Authority prior to the report being submitted.
3. What changes is EPA finalizing in today's rule?
    In today's final rule, EPA adopts the proposed rule's changes. The 
following modifications to the proposed rule were made:
    Duly Authorized Employee: The proposed rule provided examples of 
which POTW personnel could sign as a ``duly authorized employee.'' EPA 
was concerned that the specific examples

[[Page 60167]]

given (e.g., POTW Director, Plant Manager, or Pretreatment Program 
Manager) might have unintentionally limited the designation of ``duly 
authorized employee'' at a POTW in the case of an employee that did not 
have the same exact position title as any of the ones listed in the 
proposal. To avoid any confusion and provide intended flexibility, 
today's rule adopts the proposal's requirement that the duly authorized 
employee be ``an individual or position having responsibility for the 
overall operation of the facility'', yet simplifies the language by 
deleting the examples of specific POTW positions from the proposal.
    Authorization for Duly Authorized Employee: EPA clarifies in 
today's rule that the POTW's authorization of a duly authorized 
employee to sign POTW reports can be submitted to the Approval 
Authority ``together with'' the next annual report. The proposal only 
provided the option of submitting such authorization ``prior to'' the 
annual POTW report.
4. Summary of Major Comments and EPA Response
    The following is a summary of major comments received and EPA's 
response:
    Do individuals previously authorized to sign POTW reports need to 
comply with the new ``duly authorized representative'' requirements? 
Several commenters observed that individuals currently signing POTW 
reports for their program, who may have been signing such reports for 
numerous years, would now need to receive Approval Authority approval 
prior to signing the next report after today's rule becomes effective. 
The commenter suggested that EPA add a grandfather provision which 
enables such individuals to continue signing POTW reports without 
having to comply with the ``duly authorized representative'' 
requirements at 40 CFR 403.12(m).
    EPA has not adopted the commenter's suggestion. In EPA's view, the 
new language provides greater flexibility to POTWs than is currently 
provided by the Pretreatment Regulations and clarifies any uncertainty 
about which employees may be ``duly authorized'' to sign and submit 
Pretreatment reports. If the commenter chooses to continue its practice 
of delegating a duly authorized representative to sign relevant 
reports, this authorization, consistent with 40 CFR 403.12(m) ``must be 
made in writing and submitted to the Approval Authority prior to or 
together with the report being submitted.''
    EPA notes that the proposed rule made it seem as if the Approval 
Authority's approval of duly authorized representatives needed to occur 
prior to the submission of the next report. Because this is inefficient 
for the POTW, EPA modified the proposed language in 40 CFR 403.12(m), 
to indicate that the POTW can request such approval either ``prior to 
or together with'' the POTW report being submitted. It is EPA's opinion 
that this change addresses the commenters' concerns about the 
inefficiency of waiting for approval from the Approval Authority before 
submitting a report. EPA sees no reason why the POTW's request to use a 
duly authorized employee signatory not be considered by the Approval 
Authority at the same time that it receives the POTW's report.
    For Industrial User reports, why is EPA no longer requiring the 
signatory to be a high level person of authority ultimately responsible 
for the overall management of the business? One commenter disagreed 
with the change to 40 CFR 403.12(l) observing that the signatory should 
continue to be a high level person of authority who is ultimately 
responsible for the overall management of the business. EPA clarifies 
that today's rule merely provides greater flexibility in the type of 
``responsible corporate officer'' who may sign reports on behalf of an 
Industrial User. The revised requirements do not significantly alter 
the type of official designated as signatory. The Industrial User is 
still given the same level of flexibility as existed prior to today's 
rule to choose between a responsible corporate officer, a general 
partner or proprietor, or a duly authorized representative.
Net/Gross Calculations (40 CFR 403.15)
    Today's rule corrects an unintended error in the net/gross 
procedures for adjusting categorical Pretreatment Standards to reflect 
the presence of pollutants in the Industrial User's intake water. The 
error appeared to make the test for using these procedures 
unintentionally difficult to meet.
1. What were the rules in place prior to today's rulemaking?
    Net/gross calculations allow pollutants in intake water to be 
considered when developing technology-based limitations. EPA modified 
40 CFR 403.15, the section of the Pretreatment Regulations addressing 
net/gross calculations, in 1988 so that this provision would be 
consistent with the NPDES provision for net/gross which had been 
revised earlier. See discussion at 53 FR 40602-40605, October 17, 1988. 
The NPDES provision (40 CFR 122.45(g)) is an ``or'' test which allows 
net/gross adjustments either where effluent Standards are specified on 
a net basis or where control systems meet Standards in the absence of 
pollutants in the intake water. That is, meeting either condition 
allows consideration of adjustment. However, the actual language EPA 
used to modify 40 CFR 403.15 in 1988 erroneously used the term ``and'' 
instead of ``or'', thus inadvertently establishing a test in which both 
conditions would have to be met. As there are no categorical Standards 
which specify application on a net basis, this resulted in an 
unintended prohibition on the use of the net/gross provision in the 
Pretreatment Program.
2. What changes did EPA propose?
    EPA proposed to revise the language in section 40 CFR 403.15 to be 
consistent with the NPDES regulations and with the intent of the 1988 
modification. According to the proposal, categorical Pretreatment 
Standards could be adjusted on a ``net'' basis if either the applicable 
Pretreatment Standards allow for this calculation or the Industrial 
User demonstrates its control system meets those Pretreatment 
Standards.
3. What changes is EPA finalizing in today's rule?
    EPA has adopted the proposed rule change. No modifications were 
made to the proposal in the final rule.
4. Summary of Major Comments and EPA Response
    There were no significant comments on this proposed change.
Requirement To Report All Monitoring Data (40 CFR 403.12(g))
    Today's rule updates a requirement for Categorical Industrial Users 
(CIUs) to report all monitoring data to reflect the fact that this 
provision should similarly apply to non-categorical SIUs, since both 
types of Users are required to submit monitoring reports to the Control 
Authority.
1. What were the rules in place prior to today's rule?
    EPA changed 40 CFR 403.12(g) in 1988 (see 53 FR 40614, October 17, 
1988) to require all monitoring by Industrial Users to be reported. 
This was done to avoid the situation in which an Industrial User that 
performs extra sampling might select the most favorable monitoring 
result to report to the Control Authority. At the time of this change, 
only CIUs were required by the regulations to report on a regular 
basis, and therefore, this requirement was limited to CIUs. In 1990, 40 
CFR

[[Page 60168]]

403.12(h) was added to the regulations (see 55 FR 30131, July 24, 
1990), requiring all non-categorical Significant Industrial Users to 
also sample and report. However, at the time this change was made, the 
regulations at 40 CFR 403.12(g) were not updated to require all SIUs, 
categorical and non-categorical, to report all monitoring results to 
the Control Authority.
2. What changes did EPA propose?
    EPA proposed to change the Pretreatment Regulations to require all 
SIUs, both categorical and non-categorical SIUs, to report all 
monitoring results for regulated parameters at the point of compliance, 
obtained using procedures specified in Part 136, to the Control 
Authority.
3. What changes is EPA finalizing in today's rule?
    EPA adopted the proposed rule change to 40 CFR 403.12(g)(6). No 
modifications were made to the proposal in the final rule.
4. Summary of Major Comments and EPA Response
    Should non-SIUs be required to report all monitoring results? Two 
commenters suggested that EPA revise the scope of its provision to 
include all Industrial Users. While there are likely important reasons 
to apply this provision to non-SIUs on a case-by-case basis, EPA 
declines to do so in a requirement affecting all Pretreatment programs. 
First, EPA did not consider such a revision in the proposal, and it 
would be inappropriate to do so in this action. Second, while it may 
make sense to require reporting of all monitoring results for SIUs 
since they are already required to monitor and report to the POTW, non-
SIUs are not currently required by the Pretreatment Regulations to 
monitor or report. Of course, POTWs may require non-SIUs to report all 
monitoring data to POTWs on a case-by-case basis if local laws allow. 
Such a decision is a matter of local discretion.
Notification by Industrial Users of Changed Discharge (40 CFR 
403.12(j))
    Today's rule clarifies that when the Industrial User provides 
notification of a changed Discharge it should go to the ``Control 
Authority'', or the Control Authority and the POTW, where the POTW does 
not have an approved Pretreatment program.
1. What were the rules in place prior to today's rule?
    In 1988, the regulations were changed to add 40 CFR 403.12(j) (53 
FR 40614, October 17, 1988) requiring all Industrial Users to promptly 
notify the POTW of any substantial change in volume or character of 
pollutants in the User's Discharge to the POTW. This notification 
requirement did not include the Control Authority, which, in some 
cases, is not the POTW.
2. What changes did EPA propose?
    EPA proposed to expand the notification requirement in 40 CFR 
403.12(j) so that the Industrial User must notify the ``Control 
Authority'', as opposed to the ``POTW'', and in cases where the Control 
Authority and the POTW are different organizations, the Industrial User 
would notify both the Control Authority and the POTW of any substantial 
change in volume or character of pollutants in the User's Discharge to 
the POTW.
3. What changes is EPA finalizing in today's rule?
    EPA has adopted the proposed rule's revision of 40 CFR 403.12(j). 
No modifications were made to the proposal in the final rule.
4. Summary of Major Comments and EPA Response
    There were no significant comments on this proposed change.

J. Equivalent Mass Limits for Concentration Limits (40 CFR 403.6(c)(5))

    This section of today's final rule addresses the establishment of 
equivalent mass limits for concentration-based categorical Standards. 
EPA is finalizing provisions that allow Industrial Users to request 
(and, at their discretion, Control Authorities to approve) the 
conversion of concentration-based categorical limits to equivalent 
mass-based limits. The current rule requires that the Control Authority 
must control contributions to a POTW by all Significant Industrial 
Users (which include Categorical Industrial Users) through a Permit or 
equivalent individual control mechanism. See 40 CFR 403.3(t) (now found 
at 40 CFR 403.3(v)) and 40 CFR 403.8(f)(1)(iii). Today's change 
authorizes the Control Authority to calculate an equivalent mass limit 
for the Industrial User's Permit (or control mechanism) for those 
categorical Pretreatment Standards that are expressed in terms of 
concentration. Once inserted into the Industrial User's control 
mechanism, the equivalent limit replaces the promulgated concentration-
based Pretreatment Standard. See 40 CFR 403.6(c)(7). The final rule 
includes requirements that an Industrial User must satisfy in order to 
qualify for this conversion. These include a requirement for the 
Industrial User to use water conservation methods and technologies 
during the term of the Industrial User's control mechanism. The rule 
also specifies the procedures which the Control Authority must follow 
in calculating the equivalent mass limit. After the equivalent mass 
limits are in effect, the rule conditions the continued use of the 
limits on the Industrial User's compliance with several requirements, 
including, at a minimum, the maintenance and effective operation of 
treatment technologies adequate to achieve compliance with the 
equivalent mass limits, the continuous recording of flow rates, the 
notification of the Control Authority where production is expected to 
be substantially changed, and the retention of water conservation 
measures.
1. What were the rules in place prior to today's rulemaking?
    National categorical Pretreatment Standards establish different 
types of pollutant limitations for different categories. EPA has 
established categorical Pretreatment Standards that include the 
following types: (1) Concentration-based Standards that are implemented 
directly as concentration limits; (2) mass limits based on production 
rates; (3) both concentration-based and production-based limits; and 
(4) mass limits based on a concentration Standard multiplied by a 
facility's process wastewater flow. Currently, 40 CFR 403.6(c)(2) 
authorizes the Control Authority to convert production-based mass 
limits to equivalent daily mass limits or concentration limits. In 
addition, 40 CFR 403.6(d) allows the Control Authority to impose 
equivalent mass limits in addition to concentration-based Standards 
where the Industrial User is using dilution to meet applicable 
Pretreatment Standards or where the imposition of mass limits is 
appropriate. Under 40 CFR 403.6(d), both the mass limit and 
concentration limit are then enforceable, so the mass limit would not 
be an equivalent, ``in-lieu-of'' limit. The regulations do not 
currently, however, authorize establishment of alternative mass 
limitations in the case of concentration-based Standards except in the 
limited circumstances described in 40 CFR 403.6.
2. What changes did EPA propose?
    EPA proposed to revise the Pretreatment Regulations to authorize 
the Control Authority to establish equivalent mass limits in lieu of

[[Page 60169]]

promulgated concentration-based limits for Industrial Users. The 
equivalent mass limit would only be available to Industrial Users that 
had installed control measures at least as effective as the model 
treatment technologies that serve as the basis for a particular 
categorical Pretreatment Standard and that are employing water 
conservation methods and technologies that substantially reduce water 
use. The Control Authority would be required to document how the 
equivalent mass limits were derived and make this information publicly 
available.
3. What changes is EPA finalizing in today's rule?
    EPA is finalizing changes to enable Control Authorities in limited 
circumstances to express a concentration-based categorical Standard as 
an equivalent mass limit in a control mechanism issued to an Industrial 
User. The equivalent mass limit replaces the promulgated categorical 
Pretreatment Standard once it is incorporated into the Industrial 
User's control mechanism. To qualify for an equivalent mass limit, the 
CIU must meet certain eligibility conditions. These conditions require 
the CIU to: (1) Implement water conservation measures that 
substantially reduce water use; (2) use control and treatment 
technologies adequate to achieve compliance with categorical 
Pretreatment Standards, and demonstrate that it has not used dilution 
as a substitute for treatment; (3) provide monitoring data to establish 
its actual average daily flow rate and its baseline long-term average 
production rate; (4) demonstrate that it does not have daily flow 
rates, production rates, or pollutant levels that fluctuate so 
significantly that establishing equivalent mass limits would not be 
appropriate; and (5) have consistently complied with the applicable 
categorical Pretreatment Standards.
    Under the final rule, while a CIU may request an equivalent limit, 
the Control Authority has the discretion to decide whether an 
equivalent mass limit is appropriate. If the Control Authority approves 
the request, it then calculates the equivalent mass limit by 
multiplying the promulgated Pretreatment Standard (expressed as 
concentration) by the Industrial User's actual average daily flow rate 
and the appropriate unit conversion factor. For example, the unit 
conversion factor is 8.34 when multiplying a concentration limit 
(expressed as milligrams/liter) by flow (expressed as millions of 
gallons per day). The CIU is subject to the equivalent mass limit when 
its control mechanism containing the mass limit is effective. During 
the term of the control mechanism, or in a subsequent control mechanism 
term, the Control Authority may determine that it is necessary to 
revise the mass limit to reflect a significant change in the rate of 
production. The Control Authority is not required to recalculate the 
equivalent mass limits in subsequent control mechanism terms if the 
actual average daily flow rates were reduced solely as a result of 
implementing water conservation methods and technologies, and the flow 
rates used in the original calculation of the equivalent mass limits 
were not based on the use of dilution as a substitute for treatment 
pursuant to 40 CFR 403.6(d), and the Industrial User is not bypassing 
its treatment technologies pursuant to 40 CFR 403.17.
    After the Control Authority develops an equivalent mass limit and 
issues a control mechanism with the mass limits, the continued 
applicability of the equivalent mass limit depends on the Industrial 
User's continued compliance with certain requirements. To comply with 
these requirements, the Industrial User must: (1) Maintain and 
effectively operate control and treatment technologies adequate to 
achieve compliance with the equivalent mass limits; (2) record the 
facility's flow rates through the use of a continuous effluent flow 
monitoring device; (3) continue to record the facility's production 
rates and notify the Control Authority if the rates vary by more than 
20 percent from the production rates used as the basis for the 
equivalent mass limits; and (4) continue to employ the same or 
comparable water conservation measures which made the facility eligible 
for receiving the equivalent mass limits. The Control Authority should 
consider including the four conditions listed above in the CIU's 
control mechanism to make it clear to all such Industrial Users that 
continued use of the equivalent mass limits is subject to ongoing 
compliance with these minimum requirements. Failure to comply with 
these conditions will disqualify the CIU from coverage by the 
equivalent mass limit. The pre-existing concentration-based 
Pretreatment Standards will be automatically enforceable at the time of 
disqualification.
    Section 403.8(f)(1) requires that POTW Pretreatment Programs must 
have the legal authority to control the contribution to POTWs from each 
Industrial User to ensure compliance with Pretreatment Standards and 
other requirements. In the case of Significant Industrial Users, this 
control must be achieved through a Permit or other equivalent control 
mechanism. The Permit or control mechanism must contain, among other 
things ``* * * [e]ffluent limits based on applicable general 
Pretreatment Standards in part 403 of this chapter, categorical 
Pretreatment Standards, local limits, and State and applicable local 
law.'' 40 CFR 403.8(f)(1)(iii)(C). When a Control Authority develops 
equivalent mass limits under today's provision, these limits will meet 
the requirement that the Permit or control mechanism include ``effluent 
limits based on categorical Pretreatment Standards.'' As is the case 
with any equivalent Standard established under 40 CFR 403.6(c), in 
order for the Approval Authority and the public to be able to verify 
compliance by the CIUs with these equivalent Standards, the Control 
Authority will need to document how the mass limit calculations were 
derived and make the documents publicly available (i.e., to the 
Approval Authority, EPA, the general public or any third party 
requesting this information).
    Establishing mass limits that are equivalent to promulgated 
concentration-based categorical Pretreatment Standards does not 
improperly transfer Standard-setting authority to the Control 
Authority. As noted above, EPA's current regulations already require 
the inclusion in Industrial User Permits (or other control mechanisms) 
of effluent limits based on the categorical Standard. Moreover, current 
40 CFR 403.6(c)(6) provides that equivalent limits calculated in 
accordance with the regulation are deemed Pretreatment Standards for 
purposes of section 307(d) of the CWA. If a Control Authority develops 
an equivalent mass limit, in lieu of the concentration-based 
categorical Standard, the equivalent limit is a Pretreatment Standard. 
Where it is determined that the equivalent mass limit is not properly 
calculated, the Control Authority must modify the Industrial User's 
control mechanism to require immediate compliance with the correctly 
calculated limits.
    Which categorical industries are potentially affected by this 
provision? Section 403.6(c)(5) applies to qualifying indirect 
dischargers that are currently subject to Pretreatment Standards 
expressed as concentration limits. Currently, there are 14 categorical 
Pretreatment Standards that are expressed as concentration limits alone 
and are therefore eligible for equivalent mass limits under new 40 CFR 
403.6(c)(5). The following categories are included in this list:
    <bullet> Inorganic Chemicals (40 CFR part 415)

[[Page 60170]]

    <bullet> Fertilizer Manufacturing (40 CFR part 418)
    <bullet> Petroleum Refining (40 CFR part 419)
    <bullet> Steam Electric Power Generating (40 CFR part 423)
    <bullet> Leather Tanning (40 CFR part 425)
    <bullet> Glass Manufacturing (40 CFR part 426)
    <bullet> Rubber Manufacturing (40 CFR part 428)
    <bullet> Metal Finishing (40 CFR part 433)
    <bullet> Pharmaceutical Manufacturing (40 CFR part 439)
    <bullet> Transportation Equipment Cleaning (40 CFR part 442)
    <bullet> Paving and Roofing Materials (40 CFR part 443)
    <bullet> Commercial Hazardous Waste Combustors Subcategory of the 
Waste Combustors Point Source Category (40 CFR part 444)
    <bullet> Carbon Black Manufacturing (40 CFR part 458)
    <bullet> Electrical and Electronic Components (40 CFR part 469)
    In finalizing the rule, EPA is making the following changes to the 
proposed rule:
    Discretionary Use of Equivalent Mass Limits: The final rule 
emphasizes that the decision on whether to convert the CIU's 
concentration-based categorical Pretreatment Standard to an equivalent 
mass limit rests with the Control Authority. Though EPA intended that 
the Control Authority's decision would be discretionary, there was 
considerable uncertainty and concern among the commenters that the 
proposed language was not clear on this issue (e.g., ``* * * the 
Control Authority may convert the limits * * * ''). Several Industrial 
Users expressed concern that they might be compelled to accept 
equivalent mass limits. EPA has clarified the language of the final 
rule. The rule now states that Industrial Users initiate the process by 
requesting that their concentration-based limits be converted to 
equivalent mass limits. The final rule states it this way: ``* * * the 
Industrial User may request that the Control Authority convert the 
limits to equivalent mass limits. The determination to convert 
concentration limits to equivalent mass limits is within the discretion 
of the Control Authority.''
    Industrial User Eligibility Conditions: EPA has included 
requirements that the Industrial User must first meet before the 
Control Authority may establish an equivalent mass limit. Several of 
these eligibility requirements are also conditions that must be met in 
order to continue use of equivalent mass limits after becoming 
effective. The final rule includes the following requirements:
    (1) Implementation of Water Conservation: EPA has revised the 
proposed language requiring the Industrial User to be ``employing water 
conservation methods and technologies that substantially reduce water 
use'' to make it clear that current as well as future water 
conservation efforts can both qualify for the use of equivalent mass 
limits. The final rule also requires water conservation during the 
initial term of the Industrial User's control mechanism which includes 
equivalent mass limits. The revised rule language is as follows: ``the 
Industrial User must employ, or demonstrate that it will employ, water 
conservation methods and technologies that substantially reduce water 
use during the term of its control mechanism.'' See 40 CFR 
403.6(c)(5)(i)(A). The final rule also requires that the Industrial 
User ``continue to employ the same or comparable water conservation 
methods and technologies as those implemented pursuant to paragraph 
(5)(i)(A) so long as it discharges under an equivalent mass limit.'' 
See 40 CFR 403.6(c)(5)(ii)(D).
    (2) Use of Effective Control and Treatment Technologies: The 
proposed rule required ``control measures at least as effective as the 
model treatment technologies that serve as the basis for that 
particular Standard.'' The final rule revises this language, while 
retaining the principle of requiring the installation and use of 
effective control measures to meet the applicable Pretreatment 
Standards for Existing Sources (PSES) or Pretreatment Standards for New 
Sources (PSNS). The revised language is as follows: ``The Industrial 
User must * * * currently use control and treatment technologies 
adequate to achieve compliance with the applicable categorical 
Pretreatment Standard, and not have used dilution as a substitute for 
treatment.''
    The proposal discussed the fact that the Pretreatment Regulations 
in 40 CFR 403.6(d) contain a strict prohibition against the use of 
dilution as a substitute for treatment, and that requirement remains. 
This provision states that no Industrial User introducing wastewater 
pollutants into a POTW may increase the use of process wastewater or 
otherwise dilute the wastewater as a partial or total substitute for 
adequate treatment to achieve compliance with a Pretreatment Standard. 
EPA has concluded that it is appropriate to require CIUs seeking to use 
an equivalent mass limit to demonstrate their past compliance with the 
dilution prohibition in 40 CFR 403.6(d). See 40 CFR 403.6(c)(5)(i)(B). 
For example, the Industrial User can compare its current flows to the 
flows that are assumed as part of the model technology for the 
categorical Pretreatment Standard. Consistent with the dilution 
requirement, this requirement is intended to provide the Control 
Authority with a means of identifying facilities that may have used 
dilution in the past. Such CIUs would be precluded from obtaining less 
stringent equivalent mass limits by taking advantage of historically 
high flows based on dilution. The Control Authority may review 
historical monitoring and inspection reports, and process descriptions 
from the appropriate categorical Standard Technical Development 
Document published with each categorical Standard, when evaluating the 
Industrial User's demonstration of no dilution. See 40 CFR 
403.6(c)(5)(i)(B). The final rule also requires, as a condition of 
using equivalent mass limits, that Industrial Users ``maintain and 
effectively operate control and treatment technologies adequate to 
comply with the equivalent mass limits.'' See 40 CFR 
403.6(c)(5)(iii)(A). EPA revised the proposed rule language because of 
a concern that Industrial Users not be locked into a particular control 
technology or be required to make a complex technical showing that one 
treatment system is ``no less effective'' than another. By requiring 
that existing treatment be ``adequate to achieve compliance with 
applicable categorical Pretreatment Standards'' and that Industrial 
Users ``maintain and effectively operate control and treatment 
technologies adequate to comply with the equivalent mass limits'', EPA 
has concluded that the final rule language ensures that CIUs with 
equivalent mass limits continue to provide appropriate treatment. See 
40 CFR 403.6(c)(5)(ii)(A).
    (3) Establishment of Actual Average Daily Flow Rate and Baseline 
Long-Term Average Production Rate: The proposal had indicated that it 
would be sufficient to provide a ``reasonable estimate of the flow 
required to achieve the facility's production goals using BAT and in 
the absence of the water saving technology.'' See 64 FR 39570, July 22, 
1999. The final rule changes this approach to require, consistent with 
current regulations and guidance, that equivalent mass limits be based 
on the CIU's actual average daily flow rate and that flows be measured, 
as opposed to estimated, using a continuous effluent flow monitor. The 
final rule requires that the flow rate used be representative of 
current operating conditions; the actual period of flow used to develop 
the equivalent limits should reflect actual current production and 
water usage. See 40 CFR 403.6(c)(5)(i)(C). EPA

[[Page 60171]]

also conditions the use of equivalent mass limits on the continued use 
of an effluent flow monitoring device to record the facility's flow 
rates. See 40 CFR 403.6(c)(5)(iii)(B).
    In addition, the preamble of the proposed rule suggested that the 
flow component of the equivalent mass limit be based on estimated flows 
``required to achieve the facility's production goals.'' See 64 FR 
39570, July 22, 1999. EPA did not discuss in the preamble how the mass 
limit may need to change if the Industrial User changed its production 
goals, resulting in potentially substantial changes in process 
wastewater flow. In adopting a later amendment to its regulations that 
authorized the establishment in limited circumstances of equivalent 
mass limits for certain Industrial Users in the City of Owatonna, 
Minnesota, however, EPA did require Industrial Users subject to 
equivalent mass limits to notify the Control Authority where 
``production rates are expected to vary by more than 20 percent from a 
baseline production rate'' determined when the mass limit was first 
established. See 65 FR 59741 (October 6, 2000); see 40 CFR 403.19(b). 
Accordingly, EPA has modified the final rule to include a similar 
requirement for the Industrial User to provide the Control Authority 
with sufficient information to establish an average daily production 
rate. See 40 CFR 403.6(c)(5)(i)(C). The Industrial User must also 
notify the Control Authority of substantial changes in the rate so that 
the Control Authority is given an opportunity to alter the equivalent 
mass limit in the event of such changes (e.g., greater than 20 percent 
from the baseline rate). See 40 CFR 403.6(c)(5)(ii)(C) and (iii)(B).
    (4) Use of Equivalent Mass Limits for Relatively Uniform Operating 
Conditions: The final rule includes an additional requirement that the 
Industrial User demonstrate that it must ``not have daily flow rates, 
production levels, or pollutant levels that vary so significantly that 
an equivalent mass limit is not appropriate to control the Discharge.'' 
See 40 CFR 403.6(c)(5)(i)(D).
    (5) Consistent Compliance with Standards: The availability of 
equivalent mass limits is also conditioned on consistent compliance 
with applicable categorical Pretreatment Standards. The final rule does 
not specify the period during which the CIU must have demonstrated full 
compliance, but allows the Control Authority to assess the available 
compliance records to the extent that they are representative of 
current operating conditions and reflect the Industrial User's 
understanding of the regulatory obligations that must be achieved for 
compliance with these and related regulations. See 40 CFR 
403.6(c)(5)(i)(E).
    (6) Calculation of Equivalent Mass Limit: The final rule specifies 
how Control Authorities are to calculate the equivalent mass limit. The 
following language is used to describe the calculation: In the first 
term of the control mechanism, ``A Control Authority which chooses to 
establish equivalent mass limits must * * * calculate the equivalent 
mass limit by multiplying the actual average daily flow rate of the 
regulated process(es) of the Industrial User by the concentration-based 
daily maximum and monthly average Standard for the applicable 
categorical Pretreatment Standard and the appropriate unit conversion 
factor.'' See 40 CFR 403.6(c)(5)(iii)(A). The rule further provides 
that the Control Authority ``may retain the same equivalent mass limit 
in subsequent control mechanism terms if the Industrial User's actual 
average daily flow rate was reduced solely as a result of the 
implementation of water conservation methods and technologies, and the 
actual average daily flow rates used in the original calculation of the 
equivalent mass limit were not based on the use of dilution as a 
substitute for treatment pursuant to 40 CFR 403.6(d). The Industrial 
User must also be in compliance with 40 CFR 403.17 (regarding the 
prohibition of bypass).'' See 40 CFR 403.6(c)(5)(iii)(C).
    (7) Pollutants Excluded from Equivalent Mass Limits: EPA has 
adopted specific language from 40 CFR 122.45(f)(1)(i) which identifies 
the following pollutants as being inappropriate for the use of 
equivalent mass limits: pH, temperature, and radiation. See 40 CFR 
403.6(c)(5)(iv).
4. Summary of Major Comments and EPA Response
    Discretionary Use of Equivalent Mass Limits: Several commenters 
raised concerns regarding who would initiate the use of equivalent 
limits and how much discretion the Control Authority has in imposing 
these limits. A consistent theme raised among commenters representing 
Industrial Users was the concern that the proposed rule would enable 
the Control Authority to impose equivalent mass limits over the 
objection of the Industrial User. Where POTW and state commenters 
provided comments on this issue, they expressed concern that equivalent 
mass limits would create additional burden and generally emphasized 
that the decision to use equivalent mass limits to regulate a 
particular indirect discharger should be left to the POTW's discretion. 
EPA notes that these positions appear consistent with one another. The 
final rule allows for an Industrial User to request equivalent mass 
limits and emphasizes that the decision to convert concentration-based 
limits to equivalent mass limits lies within the Control Authority's 
discretion. EPA does not anticipate that an Industrial User would 
request the implementation of equivalent mass limits if it would create 
an unacceptable amount of additional burden for the facility, nor would 
the Control Authority accept an undue burden upon itself if a benefit 
would not be foreseen.
    What level of treatment must be in place prior to being eligible 
for equivalent mass limits? A few commenters objected to the proposal's 
requirement that in order to be eligible to use equivalent mass limits 
the Industrial User be utilizing control measures at least as effective 
as the model treatment technologies that serve as the basis for the 
particular categorical Standard. These commenters instead supported the 
availability of equivalent mass limits where the Industrial User could 
demonstrate that the concentration limits can be met without treatment. 
One POTW and an environmental organization took the opposite position, 
indicating that treatment must be in place prior to the use of 
equivalent mass limits. Today's final rule requires that the Industrial 
User be using control and treatment technologies adequate to achieve 
compliance with the applicable categorical Pretreatment Standard. The 
final rule also requires that the Industrial User maintain and 
effectively operate control and treatment technologies adequate to 
achieve compliance with the equivalent mass limits.
    EPA is imposing this requirement for a number of reasons. First, 
the use of technologies adequate to achieve compliance with applicable 
Standards provides the Control Authority with a level of assurance that 
qualifying Industrial Users have not been meeting their concentration-
based Standards through dilution, which is prohibited in 40 CFR 
403.6(d). Second, although water conservation typically increases the 
concentrations of pollutants in the process wastewater prior to 
treatment, facilities with on-site treatment typically show a reduction 
of pollutant loadings in the final effluent prior to its discharge to 
the POTW sewer system even where the facility has instituted water 
conservation. This reduction can be attributed to the fact that many 
wastewater treatment technologies are

[[Page 60172]]

limited more by physical/chemical properties of the pollutants in the 
wastewater, than by influent concentrations. Therefore, reducing the 
wastewater Discharge flow will generally reduce the overall pollutant 
load from the facility. This is based on the assumption that the 
reduced wastewater flow to the treatment system will allow the system 
to more successfully treat the increased pollutant concentrations in 
the wastewater treatment influent stream. This is a key reason EPA has 
concluded it is appropriate to provide this incentive for water 
conservation. More information on water conservation techniques and 
methods can be found in the rule docket (see OW-2002-0007-0091).
    In assessing whether the Industrial User has installed adequate 
control and treatment technologies, the Control Authority may review 
the corresponding categorical Standard Development Document for 
potential control options. For instance, the Development Document for 
Effluent Limitations Guidelines and Standards for the Metal Finishing 
Point Source Category (EPA 440/1-83/091, June 1983) identifies that 
PSES for the waste streams containing complexed metals is based on the 
segregation of the complexed metals waste stream with separate 
treatment for the precipitation of metals and the removal of suspended 
solids. A figure depicting the different model treatment technologies 
for the complexed metals and other wastestreams can be found in Figure 
10-1 (page X-2) of the Development Document. (pages X-1-4, and XII-1) 
The Control Authority might also review current trade association 
literature for other control options that have become available since 
the Development Document was produced, as well as sources available 
through EPA's ``Sector Strategies'' programs and EPA's Office of 
Compliance Assistance: http://www.epa.gov/sectors/program.html, http://www.epa.gov/compliance/resources/publications/assistance/sectors/notebooks/index.html.
    Prohibition Against Dilution: A few commenters indicated their 
concern that implementation of equivalent mass limits might allow 
Industrial Users to secure lenient standards through the calculation of 
equivalent mass limits based on flows that reflect diluted 
wastestreams. The proposal discussed the fact that the Pretreatment 
Regulations have a strict prohibition against the use of dilution as a 
substitute for treatment (see 40 CFR 403.6(d)). This provision 
indicates that no User introducing wastewater pollutants into a POTW 
may increase the use of process wastewater or otherwise dilute the 
wastewater as a partial or total substitute for adequate treatment to 
achieve compliance with a Pretreatment Standard. EPA has concluded that 
it should require CIUs seeking to obtain an equivalent mass limit to 
demonstrate their past compliance with the dilution prohibition in 40 
CFR 403.6(d). This requirement is intended to provide the Control 
Authority with a means of screening out those facilities that may have 
used dilution in the past in order to prevent their benefiting from 
higher than necessary flow rates when calculating a mass limit. (There 
are a number of ways the Control Authority may evaluate whether the CIU 
was diluting its flows. This evaluation can be made by comparing the 
CIU's product to flow ratio relative to that of other facilities within 
its industry or requesting an explanation of why it uses the level of 
process water that it uses.)
    How should compliance status affect an Industrial User's 
eligibility for equivalent mass limits? Several POTWs and one 
environmental organization recommended that the proposed rule be 
revised to require the Industrial User to demonstrate that it is able 
to maintain compliance with applicable Pretreatment Standards prior to 
water conservation and to restrict eligibility based on such 
compliance. EPA agrees with the commenters' suggestions. The final rule 
adopts the requirement that interested Industrial Users must have 
consistently complied with all applicable categorical Standards prior 
to the request to be subject to mass-based limits. Compliance with the 
underlying categorical Standards is an appropriate benchmark for the 
Control Authority to use in determining the eligibility of an 
individual discharger. Where the Industrial User has demonstrated 
consistent compliance, the Control Authority will be given some level 
of confidence that the User will be able to adjust to the use of a 
limit that is considered equivalent to the concentration-based 
Standard. It is EPA's view that the reverse is also true in that the 
lack of compliance may indicate a User's inability to comply with an 
equivalent limit. EPA is not specifying a minimum time period over 
which an Industrial User must be in consistent compliance. EPA notes 
that regulations in 40 CFR 403.12(o) require that Industrial Users 
maintain records of all information from any monitoring activities for 
a minimum of three years. These records should be reviewed and 
considered to the extent that they reflect compliance with current 
conditions. At a minimum, EPA expects that no Industrial User found to 
have been in significant noncompliance (SNC) at any time during the 
previous two years would be considered to have achieved consistent 
historical compliance.
    Incompatibility of equivalent mass limits with particular 
industries: One trade association commented that the use of mass limits 
is incompatible with their industry due in large part to the 
fluctuating conditions in their operations. It is EPA's view that 
certain facilities do not have operations that are compatible with the 
use of equivalent mass limits. For example, a high degree of 
variability in a CIU's flows, production, or pollutant Discharge levels 
will likely make it an inappropriate candidate to use mass limits to 
control its Discharge. For this reason, the final rule now requires 
Industrial Users to ``not have daily flow rates, production levels, or 
pollutant levels that vary so significantly that an equivalent mass 
limit is not appropriate to control the Discharge.'' See 40 CFR 
403.6(c)(5)(i)(D).
    Water Conservation as a Qualifier for Eligibility: Several 
commenters stated that the implementation of equivalent mass limits 
should not be restricted to Industrial Users that have already 
implemented water conservation measures. EPA agrees that this 
provision's intent is to encourage innovative water conservation 
methods and should not include the pre-condition that Industrial Users 
have already employed water conservation measures. This will allow 
ongoing as well as future water conservation efforts by enabling both 
to use equivalent mass limits. Regardless of whether a facility's water 
conservation methods are ongoing or have yet to be implemented, this 
final rule does require that the Industrial User demonstrate that it 
will employ water conservation methods and technologies that will 
substantially reduce water use during the term of its control 
mechanism. The Industrial User is also required to employ water 
conservation to remain eligible for equivalent mass limits.
    This final rule does not specify the amount of water conservation 
that should be achieved or that constitutes a substantial reduction in 
water use. EPA notes that several existing programs define thresholds 
that the Control Authority may consider for use in this context. For 
example:
    <bullet> The final rule for the Pretreatment Community XL (XLC) 
Site-Specific Rulemaking for Steele County, MN (65 FR 59743) of 40 CFR 
403.19(b),

[[Page 60173]]

indicates that the participating Industrial Users committed as a group 
to reduce water usage by 10% over the initial 5 year project period.
    <bullet> National Metal Finishing Strategic Goals Program promotes 
a 50% water reduction from each particular participating industry's 
baseline 1992 water usage. http://www.strategicgoals.org/coregoals.cfm.
    <bullet> EPA considers a <plus-minus> 20% change in flow rate to be 
a significant change in a flow rate. See page 2-14 of the EPA Guidance 
Manual for the Use of Production Based Pretreatment Standards and the 
Combined Wastestream Formula (Sept. 1985).
    How do facilities employ water conservation? Currently there are 
many water reduction technologies in use in manufacturing facilities 
across the United States. Many of the technologies that EPA evaluated 
when establishing the categorical Standards included water conservation 
techniques and technologies. The Technical Development Document for a 
particular categorical Standard is a valuable tool for information on 
these technologies. Technologies that reduce wastewater Discharge rates 
usually increase the concentrations of pollutants in the wastewater 
leaving the industrial operation. However, for facilities with 
wastewater treatment systems on site, these technologies may still 
reduce the final effluent pollutant loading, because many of the 
wastewater treatment technologies are limited more by physical/chemical 
properties of the pollutants in the wastewater, than by influent 
concentrations. Therefore, reducing the wastewater Discharge flow will 
generally reduce the overall pollutant load from the facility.
    In the Metal Finishing (MF) industry, facilities apply flow 
reduction practices to process baths or rinses to reduce the volume of 
wastewater discharged. One method that conserves water is cascade 
rinsing: When water is reused from one rinsing operation to another, 
less critical rinsing operation, before being discharged to treatment. 
Facilities can also reduce water use by coordinating and closely 
monitoring rinse water requirements. Matching water use to rinse water 
requirements optimizes the quantity of rinse water used for a given 
work load and tank arrangement. More information on water conservation 
techniques and methods can be found in rule record (see OW-2002-0007-
0091).
    Assessing how reduced Discharges will affect POTWs: One commenter 
asserted that EPA would be violating Section 307 if the Agency 
finalizes the proposal by failing to address the issue of whether the 
more highly concentrated wastestreams that would result from reduced 
water consumption ``would cause environmental harm at either the POTW 
or in the receiving stream or result in long-term sediment 
contamination.'' EPA disagrees that the wastestreams resulting from 
water conservation present a potential problem for the environment or 
POTWs for a number of reasons. First, in order to qualify for an 
equivalent mass limit, the Industrial User must have been in consistent 
compliance with its categorical Pretreatment Standards prior to the 
Industrial User's request to be subject to equivalent mass limits. 
Second, the Control Authority must properly convert the concentration-
based Pretreatment Standard to an equivalent mass limit using the CIU's 
actual long-term average daily flow rate. This will ensure that there 
will be no adverse impacts to human health or the environment as the 
pollutant concentrations discharged under the equivalent mass limits 
will be no greater than the concentration-based Pretreatment Standard. 
Third, EPA's existing regulations ensure continued protection of 
receiving waters and POTW operations.
    EPA emphasizes that the use of equivalent limits to regulate 
individual Industrial Users does not relieve the Control Authority of 
the need to establish and enforce local limits in accordance with 40 
CFR 403.5(d) and require compliance with the General and Specific 
Prohibitions of 40 CFR 403.5(a) and (b) which are protective of the 
POTW operations, and prevent Pass Through and Interference. 
Consequently, the use of equivalent mass limits would not be authorized 
if it resulted in a violation of any of the General and Specific 
Prohibitions or local limits established under 40 CFR 403.5(d). 
Furthermore, this provision may be implemented only following 
determination of its feasibility by Control Authorities, and not 
unilaterally by Industrial Users. Control Authorities' local limits 
will continue to ensure protection of the individual POTW operations 
and its receiving environment. Finally, the requirements of today's 
rule ensure that there will be no increase in the quantity of 
pollutants reaching the POTW as a result of adopting equivalent mass 
limits.
    How should the equivalent mass limit be calculated? One POTW 
commenter suggested that EPA clarify how to calculate the Industrial 
User's equivalent mass limit in order to specify which flow to use. EPA 
agrees that it is important to provide specific instructions on how the 
equivalent limit is to be calculated, especially with regard to which 
flow rate is the correct one to use. Today's final rule at 40 CFR 
403.6(c)(5)(iii)(A) includes the following formula to be used to 
calculate the equivalent mass limits:
    <bullet> For converting daily maximum concentration Standards to 
equivalent daily maximum mass limits: The product of the facility's 
actual average daily flow rate and the applicable concentration-based 
categorical daily maximum Standard, and the appropriate unit conversion 
factor. The unit conversion factor is 8.34 when multiplying a 
concentration limit (expressed as milligrams/liter) by flow (expressed 
as millions of gallons per day).
    <bullet> For converting monthly average concentration Standards to 
equivalent monthly average mass limits: The product of the facility's 
actual average daily flow rate and the applicable concentration-based 
categorical monthly average Standard, and the appropriate unit 
conversion factor. The unit conversion factor is 8.34 when multiplying 
a concentration limit (expressed as milligrams/liter) by flow 
(expressed as millions of gallons per day).
    It is important to note that the same flow value, the CIU's actual 
long-term average daily flow rate, is used in the calculation of both 
the daily maximum and monthly average equivalent mass limits.
    Why are equivalent mass limits calculated using the actual average 
daily flow rate? EPA specifies in 40 CFR 403.6(c)(5)(iii)(A) that the 
equivalent mass limits are calculated by multiplying the actual average 
daily flow rate by the applicable concentration-based categorical 
Pretreatment Standard and the appropriate conversion factor. The use of 
the actual average daily flow rate as the flow basis for the limits is 
consistent with existing EPA regulations and guidance. The current 
Pretreatment Regulations already require the Control Authority to 
calculate ``equivalent concentration limits'' by using the ``average 
daily flow rate of the Industrial User's regulated process 
wastewater.'' See 40 CFR 403.6(c)(4). The provision further states that 
``this average daily flow rate shall be based upon a reasonable measure 
of the Industrial User's actual long-term average flow rate, such as 
the average daily flow rate during a representative year.'' CIUs are 
elsewhere required to report in the baseline monitoring report (BMR) 
flow measurements showing the ``measured average daily and maximum 
daily flow, in gallons per day, to the POTW'' (see 40 CFR 403.12(b)(4)) 
and to include in

[[Page 60174]]

the periodic report ``a record of measured or estimated average and 
maximum daily flows'' (see 40 CFR 403.12(e)(1)).
    Perhaps most importantly, use of the long-term average daily and 
monthly flow is the only way to ensure that mass-based limits are truly 
equivalent; that is, that they do not result in any increased discharge 
of pollutants to the POTW or the environment. If a higher than average 
flow rate were used, it would be possible for the total Discharge of 
pollutants to increase, which would violate the fundamental basis of 
this streamlining change.
    EPA notes that its decision to use long-term average daily flows 
has been discussed in numerous categorical Pretreatment Standard 
rulemakings, including the final Pesticides Manufacturing Standard. See 
58 FR 50679 (September 28, 1993). In addition, Chapter 2.8 of EPA's 
Guidance Manual for the Use of Production-Based Pretreatment Standards 
and the Combined Wastestream Formula (September 1985) describes 
important considerations when determining the appropriate flow rate for 
use in developing equivalent limits including that the same average 
rate is to be used to calculate both daily maximum and maximum monthly 
average alternative limits, to avoid the use of data for too short a 
time period (particularly, ``estimating the average rate based on data 
for a few high days, weeks, or months is not appropriate'') (page 2-
14). Likewise, it is important here to use a long-term average that 
reflects current operating conditions (``actual long-term average 
flow''). Use of flow data from a period that does not represent current 
production and water use would result in mass limits that are not 
equivalent. Thus, the period of time used to compute the actual long-
term average must reflect recent production changes as well as 
reductions in water use.
    Why are continuous effluent flow monitoring devices required? The 
final rule requires that an Industrial User subject to equivalent mass 
limits must continuously monitor its flow.
    (1) Flow monitoring is required to ensure the equivalency to 
Federal categorical Pretreatment Standards: When calculating the 
equivalent limits and determining compliance, the Control Authority 
must accurately characterize the existing conditions. EPA is therefore 
requiring that the flow value used in the translation of the 
concentration limit to the equivalent mass limit and the flows utilized 
during compliance assessment be based upon a measured value using a 
continuous flow measuring device.
    Several industry commenters and one trade association representing 
municipalities indicated that they would support the use of estimation 
methods to derive facility flow rates for establishing the mass limit 
and for determining compliance. These commenters emphasized that 
estimation methods have been proven to be accurate and cost-effective. 
Some commenters supported the proposal's allowance for ``a reasonable 
estimate of the flow * * *'', but did not indicate whether they would 
support a requirement to use only measured flows. Several commenters, 
including three states, two POTWs, and one environmental interest group 
agreed that the level of accuracy obtained from flow measurements, in 
contrast to flow estimation, is required in order to ensure equivalency 
with the categorical Standards in calculating the mass limits. These 
commenters stressed that flow measurement was also necessary in order 
to adequately assess compliance with the equivalent Standard. One state 
went so far as to declare that the proposal was flawed in that it had 
not required flow measuring devices. These factors as well support 
EPA's decision to require continuous effluent flow monitors.
    (2) The relative costs and benefits of using flow monitoring 
devices should be considered: In terms of the relative cost of 
implementing flow monitoring devices, the CIU and Control Authority may 
wish to evaluate the expense of the installation of the continuous flow 
measuring device with the benefits that may be achieved by institution 
of water conservation methods and technologies. Cost effective flow 
measurement devices are estimated to cost $400-$1500. See Utility 
Supply of America, 2004-05. USA BlueBook: Everything for Water & 
Wastewater Operations, Vol. 115. In contrast, commercial/industrial 
facilities using municipal water and sewer systems incur an average 
$28,000 monthly charge for their water and sewer use (survey of 194 
U.S. cities, conducted by Raftelis Financial Consulting), consisting of 
over $12,000 per month for water charges and over $16,000 per month for 
wastewater charges (2000 Water and Wastewater Rate Survey, Exhibit 2, 
page 19, and Exhibit 5, page 44). Based on these figures, it is EPA's 
view that it is likely that benefits of water conservation will 
outweigh the cost of the meter in many situations. However, if this is 
not the case, the Industrial User does not have to request equivalent 
mass limits.
    Furthermore, measurement of water usage may bring water 
conservation benefits over and above those resulting from other 
technology changes. Accurate measurement of the water use is beneficial 
to identifying the amounts and usage of water so that behavioral 
practices can be modified and tracked. ``Monitoring the amount of water 
used by an industrial/commercial facility can provide information on 
quantities of overall company water use, the seasonal and hourly 
patterns of water use, and the quantities and quality of water use in 
individual processes. Baseline information on water use can be used to 
set company goals and to develop specific water use efficiency 
measures. Monitoring can make employees more aware of water use rates 
and makes it easier to measure the results of conservation efforts. The 
use of meters on individual pieces of water-using equipment can provide 
direct information on the efficiency of water use'' (Cleaner Water 
Through Conservation, EPA 841-B-95-002, April 1995, page 7).
    (3) Flow monitoring is required to determine compliance with 
equivalent mass limits: Accurate flow measurement is required to 
determine compliance with a mass limit based on a concentration sample 
result received from the laboratory. To such end, ``Relying on water 
consumption records when determining compliance with mass-based limits 
is not an acceptable practice'' (Industrial User Inspection and 
Sampling Manual for POTW's (EPA 831-B-91-001, April 1994, page 88). A 
permanent device that continuously records the flow allows the POTW to 
ensure compliance with mass-based limits.
    On the day(s) that the Control Authority conducts its mandatory 
one-per-year monitoring of the Industrial User, the relevant actual 
flow from the facility is required to assess whether the User is in 
compliance with its mass limits. Requiring the use of an effluent flow 
monitoring device, therefore, will also facilitate the accurate 
assessment of compliance.
    For compliance assessment purposes, EPA advises Control Authorities 
to use the following approach:
    <bullet> For a daily maximum equivalent mass limit, EPA recommends 
determining compliance by comparing the limit with the total mass of 
the pollutant discharged over the day, calculated as the product of the 
actual pollutant concentrations in the Industrial User's Discharge 
sampled pursuant to 40 CFR 403.12(g) and the actual flow from the 
Industrial User on the day the sample is taken based on measurements 
from the continuous effluent flow monitoring device and an appropriate 
conversion factor.

[[Page 60175]]

    <bullet> For an average monthly equivalent mass limit, EPA 
recommends determining compliance by comparing the limit with the sum 
of all daily mass Discharges measured during a calendar month divided 
by the number of days measured during that month. The monthly limit 
must still be met when only one discharge day is sampled.
    This approach mirrors the approach of EPA's NPDES regulations based 
on the definition of `daily discharge' in 40 CFR 122.2 defined as the 
``discharge of a pollutant measured during a calendar day or any 24-
hour period that reasonably represents the calendar day for purposes of 
sampling. For pollutants with limitations expressed in units of mass, 
the `daily discharge' is calculated as the total mass of the pollutant 
discharged over the day. For pollutants with limitations expressed in 
other units of measurement, the `daily discharge' is calculated as the 
average measurement of the pollutant over the day.''
    How are limits established for new Industrial Users? Several POTW 
commenters noted that the proposed rule was silent regarding whether 
equivalent mass limits would be available to new Industrial Users. The 
commenters observed that flow rate information is available for many 
existing Users, but a baseline of information will not exist for new 
dischargers. Today's final rule is silent regarding specific procedures 
to follow in establishing limits for new Discharges. The rule does not 
prohibit Control Authorities from calculating equivalent mass limits 
for such Dischargers. However, EPA notes that in general it will not be 
possible for new dischargers to satisfy the requirements in today's 
rule unless some historical information about them is available.
    First, recognizing that 40 CFR 403.6(c)(5)(i)(E) requires the 
Industrial User to ``have consistently complied'' with Pretreatment 
Standards'', before considering the use of equivalent mass limits, the 
Control Authority will need to allow for a sufficient period of time to 
pass in order to properly assess the User's compliance record.
    Second, the new discharger will need some time to collect an 
adequate amount of flow rate data from its continuous effluent flow 
monitor to establish its actual average daily flow rate and, in turn, 
to provide the Control Authority with sufficient information to 
calculate the equivalent mass limit. Although 40 CFR 403.6(c)(5)(i)(C) 
does not specify a minimum amount of time over which the long-term flow 
rate is developed, the rule does specify that the flow rate must be 
``representative of current operating conditions.'' Therefore, EPA 
recommends that the Control Authority establish some minimum period of 
time during which it will require the new discharger to have monitored 
its flow before considering equivalent mass limits.
    Third, new dischargers will be subject to Pretreatment Standards 
for New Sources (PSNS), and as such will be expected to begin 
discharging in conformance with Standards that represent the most 
stringent controls attainable through the application of the best 
available demonstrated control technology for pollutants that pass 
through, interfere with, or are otherwise incompatible with the 
operation of POTWs. 67 FR 64219 (October 17, 2002). EPA does not 
anticipate that new dischargers will immediately need to reduce water 
use. Presumably, these dischargers will have had the opportunity prior 
to commencing their discharge to implement optimal water consumption 
practices that meet their own production demands and cost efficiency 
standards. Over time, and after considering such factors as the cost of 
water and production needs, the facility may become interested in 
pursuing further water conservation measures.
    Recalculation of equivalent mass limits to adjust for production 
changes during the term of the control mechanism: A few commenters were 
concerned that once set, the equivalent mass limits would be locked in 
place permanently and Industrial Users would be forced to comply with 
one mass limit forever. They specified that this would potentially 
restrict a facility from increasing production. The final rule requires 
that the Industrial User notify the Control Authority whenever 
production rates are expected to vary by more than 20 percent from 
baseline production rate. Upon notification of a change in production 
rate, the Control Authority would then reassess the appropriateness of 
the equivalent mass limit. The Control Authority may determine that it 
is necessary to change the equivalent mass limit to reflect flow 
changes that may result from substantial changes in production. As such 
production-based flow changes may occur, the approach EPA is adopting 
for alternative mass limits is consistent with regulations at 40 CFR 
403.6(e) that discuss alternative limits based on the combined 
wastestream formula:
    ``The Industrial User shall comply with the alternative daily 
maximum limit and monthly limits fixed by the Control Authority until 
the Control Authority modifies the limits or approves an Industrial 
User modification request. Modification is authorized whenever there is 
a material or significant change in the values used in the calculation 
to fix alternative limits for the regulated pollutant.''
    Recalculation of equivalent mass limits in subsequent terms of the 
Industrial User's control mechanism: A few commenters asked whether and 
to what extent equivalent mass limits would need to be recalculated to 
reflect changed circumstances at the facility prior to reissuance of 
the control mechanism. When a Control Authority reissues an Industrial 
User's control mechanism, the Control Authority may determine that 
changed conditions suggest the need to revisit the equivalency of the 
mass limits to the categorical Pretreatment Standards that were 
included in the prior control mechanism. For example, EPA anticipates 
that the Control Authority may choose not to recalculate equivalent 
mass limits if effluent flow was reduced as the result solely of the 
implementation of water conservation techniques and methods. See 40 CFR 
403.6(c)(5)(iii)(C). However, the Control Authority may determine that, 
in cases where a reduction in discharged effluent flow was accompanied 
by a decrease in production, a reevaluation is warranted. This 
reevaluation is consistent with EPA's long-standing approach under 
existing section 403.6(c) with respect to equivalent mass or 
concentration limits. See 53 FR 40563-67 (October 17, 1988).
    Today's rule conditions an Industrial User's eligibility for the 
establishment of equivalent mass limitations on the requirement that 
the Industrial User is providing adequate treatment to achieve 
compliance with the Pretreatment Standards and is not using dilution to 
achieve compliance in lieu of treatment (in accordance with 40 CFR 
403.6(d)). Industrial Users must continue to operate and maintain their 
treatment systems as a requirement to continue to benefit from the 
flexibility granted by equivalent mass limitations. This approach, in 
addition, is consistent with 40 CFR 403.17, which prohibits the 
intentional diversion of wastestreams, including categorical process 
wastewater, from any portion of an Industrial User's treatment facility 
unless such is ``unavoidable to prevent loss of life, personal injury, 
or severe property damage [and] there were no feasible alternatives to 
the bypass, such as the use of auxiliary treatment facilities, 
retention of untreated wastes, or maintenance during normal periods of 
equipment downtime,'' and proper notice has been submitted to the 
Control Authority. Where a bypassing of treatment may still result in 
discharged

[[Page 60176]]

effluent that complies with the applicable Pretreatment Standards or 
Requirements, an Industrial User may only allow the bypass of its 
treatment facility if it ``is for essential maintenance to assure 
efficient operation.'' Therefore, Industrial Users, in order to 
continue to qualify for equivalent mass limit conversions from 
categorical Pretreatment Standards, must continue to effectively 
operate and maintain their control and treatment technologies.
    Is this provision consistent with the Clean Water Act? One 
commenter objected to the proposed rule stating that EPA lacks the 
authority to delegate its standard-setting authority to Control 
Authorities, an authority which Congress gave to EPA alone under 
Section 307 of the Clean Water Act. The commenter reasoned that the 
provision would require that local authorities make ``significantly 
more complicated decisions than mere arithmetic'', and that the 
proposal would require them to become ``expert in both pollution 
control and water conservation in each regulated industry.''
    EPA is promulgating the changes to its Pretreatment Regulations in 
part under section 307(b) of the Clean Water Act. Section 307(b) 
clearly authorizes EPA from time to time to revise Pretreatment 
Standards as ``control technology, processes, operating methods or 
other alternatives change.'' Therefore, today's action is not in 
violation of section 307(b) to the extent this provision authorizes 
Control Authorities to establish equivalent mass limits for the 
Pretreatment Standards for certain categories of industry subject to 
concentration-based Standards. See list of affected industries in 
Section III.J.3 above. As EPA has explained, the amendments to the 
regulations will facilitate both User's compliance and POTW oversight 
for industries engaging in water conservation, a practice EPA wants to 
encourage.
    EPA's decision to authorize the establishment of equivalent mass 
limits for Industrial Users in limited circumstances is not 
inconsistent with its decision in some circumstances to adopt 
categorical Pretreatment Standards for specific industry categories 
whose Standards are expressed in 40 CFR Subchapter N as concentration 
limits. A number of reasons support this conclusion. First, EPA's 
general preference in most cases is to express wherever possible 
effluent limitations and Pretreatment Standards in terms of mass 
limitations. EPA's decision to establish concentration-based 
Pretreatment Standards, however, for certain industrial categories, is 
the result, in part, of the wide variation in process water use within 
a particular industrial category. These variations prevented EPA from 
developing water allowances associated with particular achievable 
treatment technologies. Due to the complexity and variation among 
facilities covered by categorical Standards, EPA did not have enough 
data, could not adequately measure production or could not find a 
consistent production normalizing relationship in order to establish 
mass limits on a nationwide basis. The effect of concentration limits 
also is, over time, to reduce mass Discharges of pollutants as water 
use is reduced in some circumstances. But concentration limits may in 
some circumstances serve as a disincentive to water conservation.
    Second, the establishment of an equivalent mass limit would not 
result in any increase in the mass of pollutants discharged. 
Eligibility for an equivalent limit is dependent on a number of 
conditions including implementation of water conservation measures and 
demonstration of a history of compliance with the concentration-based 
Pretreatment Standard. As noted above, the implementation of water 
conservation efforts may have already resulted in some reduction of 
total mass Discharges. Further, because the mass limit is based on 
water use during the period of compliance with the concentration limit, 
in no event, could mass Discharges under the new equivalent limit 
exceed these mass Discharge levels. Another condition for the 
establishment of mass limits is that the facility report to the 
Permitting Authority in the event of substantial changes in production 
rates. This provides the Permitting Authority with an opportunity to 
monitor the equivalent limits and determine whether some modification 
to the limit may be required.
    There will be no adverse consequences either to POTWs or to 
receiving waters from the adoption of the provision authorizing the 
expression of concentration-based Pretreatment Standards as mass 
limits. Industrial Users must continue to comply with the General and 
Specific Prohibition in 40 CFR 403.5(a) and (b). Thus, Discharges under 
an equivalent limit may not result in Discharges that result in Pass 
Through or Interference, create hazards to the POTW, or threaten the 
health and safety of POTW workers. Section 403.5(c) would prohibit the 
establishment of an equivalent mass limit if the equivalent limit would 
result in a violation of these General and Specific Prohibitions.
    Finally, EPA disagrees that the final rule would illegally transfer 
the Agency's Standard-setting authority to Control Authorities. As 
noted previously, a Control Authority is already required to translate 
categorical Pretreatment Standards into Permit (or control mechanism) 
effluent limits. EPA also disagrees with the commenter's observation 
that this provision would be too complicated for Control Authorities to 
use and oversee. EPA notes that the use of this provision is solely at 
the discretion of the Control Authority. If a particular Control 
Authority is concerned that it does not have the expertise to develop 
and oversee equivalent mass limits, today's final rule does not in any 
way allow the Industrial User to demand that the Control Authority 
convert existing concentration-based Standards to equivalent mass 
limits or require that the Control Authority implement mass-based 
limits if requested by the Industrial User. As a matter of daily 
implementation of approved Pretreatment Programs, states and POTW 
Control Authorities conduct complex activities: Review Baseline 
Monitoring Reports (40 CFR 403.12(b)) and other data to issue control 
mechanisms to Industrial Users, calculate production-based standards 
and alternative limits using the Combined wastestream formula when 
necessary, and evaluate and assess the POTW plant processes to 
determine technically based local limits that are protective of Pass 
Through and Interference.
    Public Review and prior Approval Authority approval: Many 
commenters (21) did not support requiring public and/or Approval 
Authority review of an Industrial User's proposed mass limit prior to 
Control Authority approval. Most were concerned that such a requirement 
would create additional administrative burden. EPA notes that this 
provision is intended to allow the Permit limitation to be expressed in 
an equivalent manner and is not anticipated to require a change in a 
Control Authority's enabling legislation to issue and enforce control 
mechanisms. Changes affecting individual Industrial Users are not 
substantial modifications within the principles of 40 CFR 403.18(b)(6). 
`` `Changes to the POTW's control mechanism' refers to a change in the 
type of mechanism used (e.g., permit versus orders) and not to 
change[s] in one facility's permit or to changes in the boilerplate or 
other details of the permit.'' (62 FR 38408) However, the new 
equivalent limit is subject to review

[[Page 60177]]

as part of routine Approval Authority oversight activities, such as a 
Pretreatment Compliance Inspection or a Control Authority Audit, as are 
other control mechanisms that implement categorical Standards, local 
limits, and any other equivalent limits. Also, in accordance with 
current regulations, Industrial User Permit files and information 
necessary for determining Permit limitations and compliance, must be 
publicly available. Therefore, EPA has decided not to require 
additional review or approval mechanisms for implementation of 
equivalent mass limits.

K. Oversight of Categorical Industrial Users (40 CFR 403.3(v)(2), 
403.8(f)(2)(v), 403.12(e), (g), (i), (q)

    Today's rule authorizes a Control Authority to reduce certain of 
its oversight responsibilities and sampling and inspection requirements 
for a newly established class of indirect discharger, the ``non-
significant categorical Industrial User'' (NSCIU). A NSCIU is a 
discharger that discharges no more than 100 gallons per day of total 
categorical wastewater to the POTW. Today's final rule also allows 
Control Authorities to reduce the reporting requirements for certain 
Categorical Industrial Users with a record of consistent compliance 
with applicable Pretreatment Standards and Requirements in the 
following circumstances. Reduced reporting may be approved when the 
Industrial User's categorical wastewater flow does not exceed (1) the 
smaller of 5,000 gallons per day or 0.01 percent of the POTW's design 
dry weather hydraulic capacity; (2) 0.01 percent of the POTW's design 
organic treatment capacity; and (3) 0.01 percent of the maximum 
allowable headworks loading (MAHL). The POTW may also now be authorized 
to reduce its own required annual inspections and monitoring of those 
Categorical Industrial Users eligible for reduced reporting.
1. What are the existing rules?
    The current regulations require certain minimum oversight of SIUs 
by POTWs with Approved Pretreatment Programs (and States acting as 
Pretreatment Control Authorities). The required minimum oversight 
includes inspection and sampling of each SIU annually, reviewing the 
need for a slug control plan, and issuing a Permit or equivalent 
control mechanism with a duration not to exceed five years (40 CFR 
403.8(f)(1)(iii) and (2)(v) and 403.10(f)(2)(i)). Industrial Users that 
are not SIUs are not specifically subject to this oversight.
    The definition of ``Significant Industrial User,'' previously at 40 
CFR 403.3(t) (now found at 40 CFR 403.3(v)), includes two types of 
facilities. The first includes all Industrial Users that are subject to 
categorical Pretreatment Standards under 40 CFR 403.6 and 40 CFR 
chapter I, subchapter N. The facilities subject to these Standards are 
now described as Categorical Industrial Users (CIUs). There are no 
current exceptions to the classification of all CIUs as SIUs. The 
second category of facilities included in the definition of SIU are 
certain facilities that are not CIUs, that Discharge 25,000 gallons per 
day or more of process wastewater, facilities that contribute a process 
wastestream constituting 5 percent or more of the POTW's capacity, and 
any Industrial User that the Control Authority designates on the basis 
that it has a reasonable potential for adversely affecting the POTW's 
operation or for violating any Pretreatment Standard or requirement. 
The Control Authority may exclude facilities meeting any of the second 
category's criteria from the SIU definition based upon a finding that 
it does not have a reasonable potential to adversely affect the 
operation of the plant or violate any Pretreatment Standard or 
requirement. However, a Control Authority may not similarly exclude 
CIUs from the classification as an SIU.
    The regulations require that all CIUs submit to their Control 
Authority twice per year, unless required more frequently, a report 
indicating the flow, nature, and concentration of pollutants in their 
effluent which are limited by the applicable categorical Pretreatment 
Standards (40 CFR 403.12(e)(1)). The report must be based on data 
obtained through sampling and analysis of the effluent which is 
representative of conditions occurring during the reporting period at a 
frequency necessary to assess and assure compliance with applicable 
Standards (40 CFR 403.12(g)). The regulations make clear that these are 
minimum requirements and Control Authorities have the flexibility to 
increase sampling and reporting requirements.
2. What changes did EPA propose?
    EPA proposed to allow Control Authorities to exempt certain CIUs 
from the definition of SIU. The proposal would have defined NSCIUs as 
(1) facilities that never discharge untreated concentrated wastes that 
are subject to the categorical Pretreatment Standard as identified in 
the development document for the Standard, and never discharge more 
than 100 gallons per day (gpd) of other process wastewater, and (2) 
Industrial Users subject only to certification requirements after 
having met baseline monitoring report requirements (e.g., pesticide 
formulators and packagers). In addition to proposing to set the NSCIU 
definitional threshold at 100 gpd, EPA also requested comment on 
alternative criteria for determining ``non-significant'' status, such 
as a percentage of a POTW's total flow discharged by a particular 
Categorical Industrial User (64 FR 39574, July 22, 1999).
    In conjunction with the establishment of a NSCIU category, EPA also 
proposed that such Users not be subject to minimum inspection and 
sampling requirements. Instead, the new requirements would have allowed 
the Control Authority to establish the appropriate level of inspection 
and sampling for these facilities. In addition, EPA would have 
established new minimum reporting requirements for NSCIUs. EPA proposed 
that at a minimum, a non-significant facility would be required to 
annually report and certify its status as a non-significant facility, 
and certify that it is in compliance with the applicable Pretreatment 
Standards. A Control Authority could have required more frequent 
sampling, inspections, or reporting as it finds necessary to ensure 
compliance with the categorical Standards.
3. What changes is EPA finalizing in today's rule?
    EPA is establishing an NSCIU category based on the 100 gpd 
threshold. If a POTW chooses to treat a qualifying Categorical 
Industrial User as an NSCIU, the oversight requirements for the NSCIU 
(and POTW with respect to the NSCIU) will be significantly reduced. In 
response to support among commenters for establishing alternative 
criteria for oversight reduction, EPA is also creating a ``Middle 
Tier'' category of Categorical Industrial Users which will still be 
considered SIUs, but will be eligible for reductions in reporting and 
Control Authority monitoring and inspections. These changes will be 
discussed in detail below.
    In the period before the Agency proposed regulatory changes to 
streamline elements of its Pretreatment Regulations, EPA engaged in an 
extensive effort to solicit the views of the interested public. In 
1995, EPA's Office of Wastewater Management initiated an evaluation of 
all of the General Pretreatment Regulations in 40 CFR Part 403 in order 
to identify streamlining opportunities. Based on input from various 
stakeholders, EPA developed issue papers that

[[Page 60178]]

summarized 11 areas in which the Pretreatment Regulations might be 
streamlined. In May 1996, the issue papers were distributed to a broad 
base of external stakeholders (States, cities, trade associations, 
professional organizations, and environmental interest groups). As EPA 
explained in the preamble to the proposal (64 FR 39573-74, July 22, 
1999), in 1997, EPA solicited comment on revising the definition of 
Significant Industrial User to reduce the reporting and permitting 
requirements for certain non-significant facilities that are subject to 
National categorical Pretreatment Standards. An earlier Water 
Environment Federation (WEF)/Association of Metropolitan Sewerage 
Agencies (AMSA) Pretreatment Streamlining Workshop had recommended 
excluding facilities under 100 gpd from the definition of Significant 
Industrial User, exempting from the definition of SIU any CIU that has 
no reasonable potential to adversely affect the POTW's operation and 
allowing Control Authorities more flexibility in the oversight of 
facilities that would continue to be defined as SIUs. EPA's 1997 letter 
sought comment on these recommendations and also on whether to allow 
POTWs more flexibility in sampling SIUs that had been in consistent 
compliance.
    Most commenters on the earlier options supported allowing POTWs to 
reduce oversight of non-significant CIUs, recommending NSCIU be defined 
as below thresholds of from 100 gpd to 4,000 gpd. Some commenters 
opposed any definition based on flow and preferred one based on total 
mass or impact on the POTW. The record to the proposed rule included 
all of the material submitted by commenters as well as the information 
developed by the WEF/AMSA workshop.
    While EPA based its 1999 proposed streamlining revision of the 
definition of SIU on a 100 gpd threshold, the Agency did seek comments 
on a number of alternative thresholds that reflected the earlier 
suggestions from the public. As EPA stated:
    ``In today's proposal EPA is again requesting comment on 
alternative criteria for determining non-significant status. Such 
alternative criteria might include a higher flow cutoff or a numeric 
cutoff based on some alternative criteria such as the estimated mass of 
pollutant loadings or the percentage of a POTW's total flow discharged 
by a particular CIU. Alternatively, the criteria might be narrative and 
include a qualitative description of what constitutes a Significant 
Industrial User. Commenters are encouraged to provide data on the 
likely effects of alternate criteria, including the number of CIUs that 
would be eligible for non-significant status and any adverse impacts on 
POTWs or the environment that might result.'' 64 FR 39574, July 22, 
1999.
    Today's final rule provides reduced oversight responsibilities for 
POTWs and reporting requirements for CIUs that represent an 
accommodation between the alternatives considered by EPA in the 
proposal (including the recommendations earlier submitted to the Agency 
and discussed in detail in the proposal) and those suggested by 
commenters in response to the proposal's solicitation of views. Thus, 
the final rule combines EPA's proposed approach to non-significant CIUs 
and reduced POTW oversight requirements, with the suggestions of many 
commenters provided both in comments before and after proposal that EPA 
consider thresholds based on POTW treatment capacity. Consequently, the 
final rule adopts a fixed threshold requirement for NSCIUs, while 
establishing threshold expressed in terms of percentage of POTW flows 
for the ``Middle Tier'' CIUs. EPA views this approach as balancing the 
need for required minimum oversight of larger dischargers with the 
appropriate flexibility to POTWs to target oversight resources where 
they will provide the greatest benefit in terms of reducing the risk to 
the POTW and the environment.
    For the reader's assistance, the following chart distinguishes 
between NSCIUs, ``Middle Tier'' Significant Categorical Industrial 
Users, and all other Significant Categorical Industrial Users:

----------------------------------------------------------------------------------------------------------------
                                          Control mechanism      Minimum CIU reporting   Minimum POTW inspection/
                                              required?               requirements        sampling requirements
----------------------------------------------------------------------------------------------------------------
NSCIUs...............................  No*....................  Certification only (no   Not required.
                                                                 reporting), one time
                                                                 per year.
``Middle Tier'' Significant CIU......  Yes....................  One time per year (if    One time every other
                                                                 representative of        year.
                                                                 Discharge conditions
                                                                 during reporting
                                                                 period).
All Other Significant CIUs...........  Yes....................  Two times per year (at   One time per year.
                                                                 a minimum).
----------------------------------------------------------------------------------------------------------------
* If the Control Authority determines that an existing NSCIU no longer meets a required criterion for being
  categorized as non-significant, such as the requirement to be in consistent compliance with Pretreatment
  Standards and Requirements, the User becomes an SIU and must be issued a control mechanism.

    EPA emphasizes that a Control Authority's decision to categorize 
certain CIU facilities as ``non-significant'' or ``Middle Tier'' does 
not in any way relieve the affected CIUs of the duty to comply with the 
applicable categorical Pretreatment Standards. The provisions in this 
final rule merely affect the reporting and inspection frequency imposed 
on these Users.
a. Non-Significant CIU--Definition and Oversight Requirements
    Today's final rule adopts the proposed definition of ``non-
significant categorical Industrial User'' (NSCIU) with minor 
modifications and the proposal's approach of, if the Control Authority 
chooses to do so, reducing required oversight for such Users. A few 
modifications, which will be detailed further below, were made to the 
proposed provisions in response to concerns raised by commenters. The 
final rule retains the 100 gpd threshold for defining a NSCIU, as well 
as the condition that the User never discharges ``untreated 
concentrated wastes''. However as pointed out by one commenter, the 
proposed rule would have applied the 100 gpd threshold to ``other 
process wastewater'' rather than ``categorically regulated process 
wastewater,'' which the commenter thought was a more appropriate basis 
for the threshold. Because facilities are deemed to be CIUs by virtue 
of their discharges of categorical process wastewater, rather than 
process

[[Page 60179]]

wastewater generally, EPA agrees that it is appropriate to base the 
threshold for non-significant CIUs on their discharge of categorically-
regulated process wastewater and has revised the definition of NSCIU 
accordingly in the final rule. As was the case with the proposed rule, 
in order to be considered an NSCIU, the User must fulfill its annual 
certification requirement. The final rule also retains the Control 
Authority's discretion to reduce the NSCIU's sampling and reporting 
requirements as long as the User annually reports and certifies that it 
still meets the definition of a NSCIU. In addition, because the User is 
no longer an SIU, there is no requirement to control the User through a 
permit or other control mechanism. POTWs will be required to provide a 
list of the facilities that are being regulated as non-significant CIUs 
in the POTWs annual Pretreatment report. After an initial list is 
provided, deletions and additions should be keyed to the previously 
submitted list.
    Regardless of whether an Industrial User is determined to be a 
NSCIU, it is still a categorical discharger and, as such, is still 
required to comply with applicable categorical Pretreatment Standards 
and related reporting and notice requirements in 40 CFR 403.12(b), (c), 
(d), (f), (j), and (p). Control Authorities will still be required to 
perform the same minimum oversight of a NSCIU that is required for 
other facilities that are not SIUs, including notifying the CIU of its 
status and requirements (403.8(f)(2)(iii)); receiving and reviewing 
required reports (403.8(f)(2)(iv) and 403.12(b), (d), & (e)); random 
sampling and inspection (403.8(f)(2)(v)); and investigating 
noncompliance as necessary (403.8(f)(2)(vi)).
    Why did EPA choose the 100 gpd threshold for NSCIUs? EPA recognizes 
that any numeric flow cutoff will have both advantages and 
disadvantages. The 100 gpd criterion was supported by commenters, 
although many suggested alternative, higher volume cutoffs. The 100 gpd 
flow cutoff is a conservative number. EPA estimates 15 percent of 
current CIUs might be eligible for NSCIU status, based on an 
extrapolation of data from a range of POTWs across the country.
    Does EPA expect the annual NSCIU certification to be supported by 
sampling data? Today's final rule does not require that each 
certification statement be supported by sampling data. NSCIU 
facilities, however, must have a reasonable basis for their compliance 
certifications. When sampling is not performed, the non-significant CIU 
must describe the basis for its compliance certification, such as, for 
example, the absence of changes in processes that generate categorical 
wastewaters or in raw materials used since the last sampling data was 
analyzed.
    Does EPA expect the Industrial User or Control Authority to perform 
annual monitoring for NSCIUs? Today's final rule does not establish any 
minimum sampling requirements for the Industrial User or Control 
Authority. However, EPA recommends that sampling by the Industrial User 
or Control Authority be performed from time to time to confirm 
compliance with the categorical Standards.
Significant Changes to the Proposed Rule
    EPA made the following significant changes to the provisions 
affecting NSCIUs:
    Discharge Volume Cutoff: The definition of NSCIU now specifies that 
the 100 gpd cutoff is to be measured as the ``total categorical 
wastewater (excluding sanitary, non-contact cooling and boiler blowdown 
wastewater, unless specifically included in the Pretreatment 
Standard)'' discharged. The term ``total'' clarifies that the volume 
discharged is a maximum limit. Averaging the Discharge volume for 
purposes of meeting the 100 gpd cutoff is not authorized (e.g., 
enabling a discharger to exceed the limit on some days as long as the 
average is 100 gpd or less). EPA had requested comments in the proposal 
on whether to allow the non-significant definition to include 
facilities that discharge up to 500 gallons of process wastewater once-
per-week. EPA has concluded that requiring a definitive, total daily 
cutoff is the easiest and most efficient way to oversee and implement 
the NSCIU provisions.
    EPA also notes that the definition of NSCIU specifically enables 
Users to exclude non-categorical wastewater Discharges such as 
sanitary, non-contact cooling and boiler blowdown wastewater in the 
determination of the Discharge volume, unless specifically included in 
the Pretreatment Standard. See 40 CFR 403.3(v)(2).
    Additional Definitional Conditions: The final rule includes a few 
modifications to the conditions that a User must meet to be considered 
``non-significant''. These modifications include:
    (1) Consistent Compliance with Pretreatment Standards: In order to 
be considered an NSCIU, the User, prior to the Control Authority's 
findings, must have consistently complied with all applicable 
categorical Pretreatment Standards and Requirements. See 40 CFR 
403.3(v)(2)(i) and discussion above regarding the consistent compliance 
criteria for equivalent mass limits.
    (2) Documentation and Certification of Compliance: The final rule 
also requires that the NSCIU certify that its Discharge is in 
compliance with all applicable categorical Pretreatment Standards and 
requirements and annually submit the certification using the statement 
in 40 CFR 403.12(q). See 40 CFR 403.3(v)(2)(ii).
    Signatory Requirements: Today's final rule clarifies that the 
annual certification statement must be signed in accordance with 
requirements in 40 CFR 403.12(l). See 40 CFR 403.12(q).
    Annual List of NSCIUs: The final rule makes explicit what was 
discussed in the preamble to the proposed rule that a Control Authority 
is required to include a list of Users considered to be NSCIUs in its 
annual report to the Approval Authority. See 40 CFR 403.12(i).
    Annual Evaluation of NSCIU Status: The proposed rule is modified to 
require that a Control Authority evaluate, at least once per year, 
whether an Industrial User previously determined to be an NSCIU still 
meets the ``non-significant'' criteria in 40 CFR 403.3(v)(2). See 40 
CFR 403.8(f)(2)(v). EPA anticipates that this evaluation will primarily 
involve the Control Authority's verification that certification forms 
have been submitted by the NSCIUs documenting continued eligibility for 
NSCIU status and compliance with applicable Pretreatment Standards and 
Requirements.
b. Middle Tier Categorical Industrial Users--Definition and Oversight 
Requirements
    EPA is today establishing a new category of Categorical Industrial 
Users (CIUs), the ``Middle Tier'' CIUs. The term ``Middle Tier'' is 
used because the applicable requirements for these CIUs are more 
stringent than for NSCIUs, but authorize less reporting than for other 
(larger) Significant CIUs. Note that both ``middle tier'' and other 
CIUs (except NSCIUs) are still considered SIUs. Refer to above table 
comparing applicable requirements of all types of CIUs in Section 
III.K.3. An Industrial User may be considered a Middle Tier CIU if its 
Discharge of categorical wastewater does not exceed any of the 
following:
    <bullet> 0.01 percent of the design dry weather hydraulic capacity 
of the POTW, or 5,000 gpd, whichever is smaller, as measured by a 
continuous effluent flow monitoring device unless

[[Page 60180]]

the Industrial User discharges in batches;
    <bullet> 0.01 percent of the design dry weather organic treatment 
capacity of the POTW; and
    <bullet> 0.01 percent of the maximum allowable headworks loading 
for any pollutant for which approved local limits were developed by a 
POTW.
    The Control Authority must also demonstrate that the CIU has not 
been in significant noncompliance for any time in the past two years, 
and that the CIU does not have daily flow rates, production levels, or 
pollutant levels that vary so significantly that decreasing the 
reporting requirement for this Industrial User would result in data 
that are not representative of conditions occurring during the 
reporting period. See 40 CFR 403.12(e)(3)(i-iii).
    What are the reporting and monitoring requirements for Middle Tier 
CIUs? Once eligible for Middle Tier CIU status, the Control Authority 
may reduce the required periodic monitoring report for such Users from 
a minimum of twice per year to a minimum of once per year. EPA notes 
that any reduction in reporting must satisfy the requirements of 40 CFR 
403.12(g)(3) which states that reports such as Industrial User periodic 
monitoring reports must be based upon ``data obtained through 
appropriate sampling and analysis performed during the period covered 
by the report, which data are representative of conditions occurring 
during the reporting period.'' (emphasis added) Therefore, it is 
important that facilities authorized to use the new minimum sampling 
frequency conduct their sampling on representative wastewater flows. 
For example, while certain batch dischargers will have sufficiently 
uniform processes, such that reduced sampling will be representative 
and able to meet the Middle Tier criterion concerning variable flow 
rates, production levels, or pollutant levels (40 CFR 
403.12(e)(3)(iii)), other batch dischargers may vary their processes 
seasonally or unpredictably, hence making it difficult for the Control 
Authority to demonstrate both that a minimum of one sample per year 
will be representative, and that the discharger complies with 40 CFR 
403.12(e)(3)(iii). In addition, POTWs may also reduce their own 
obligations to inspect and sample these Middle Tier CIUs from once per 
year to once every two years. See 40 CFR 403.8(f)(2)(v)(C).
    Why is EPA proposing the Middle Tier CIU category? In the preamble 
to the proposed rule, EPA solicited comment on ``alternative criteria 
for determining non-significant status * * * [such as] the percentage 
of a POTW's total flow discharged by a particular CIU.'' See 64 FR 
39574 (July 22, 1999). Eighteen (18) POTW commenters responded by 
suggesting that EPA adopt the following three tier system. The first 
tier would encompass CIUs discharging less than 100 gpd. Referred to as 
``de minimis'' CIUs, this tier is similar to today's promulgation of 
the NSCIU category. The second tier (referred to by the commenters as 
``non-significant CIUs'') would have included CIUs that meet all of the 
following conditions:
    <bullet> The CIU's discharge of categorical wastewater does not 
exceed 0.01 percent of the design dry weather hydraulic capacity of the 
receiving POTW, nor does it exceed 10,000 gpd;
    <bullet> The CIU's discharge of categorical wastewater does not 
exceed 0.01 percent of the design dry weather organic treatment 
capacity of the receiving POTW;
    <bullet> The CIU's discharge of categorical wastewater does not 
exceed 0.01 percent of the maximum allowable headworks loading (MAHL) 
for the receiving POTW of any pollutant detected at the POTW headworks 
for which the CIU is subject to a categorical Pretreatment Standard; 
and
    <bullet> The CIU has not been in significant noncompliance (SNC) 
for the most recent four consecutive six-month periods.
    Where a CIU met the criteria of the second tier, the Control 
Authority would have the option of reducing the Industrial User's 
monitoring to once per year (as compared to the current minimum of 
twice per year) and the Control Authority's inspection and monitoring 
requirements to once every two years (as compared to the current 
minimum requirement of once every year). It is important to note that 
the commenters' second tier would not have enabled the Control 
Authority to reduce oversight requirements to the degree that the first 
tier would. The third tier of the commenters' system would have 
included all other CIUs subject to the full array of oversight 
requirements.
    In August 2000, EPA approved a project under the Agency's Project 
XL program for the Metropolitan Water Reclamation District of Greater 
Chicago (MWRDGC) to pilot the use of the ``non-significant CIU'' 
criteria supported by the POTW commenters on the proposed rule. In 
exchange for agreeing to a variety of measures to improve the level of 
environmental performance by the POTW, MWRDGC was given authority to 
apply the ``non-significant CIU'' criteria (similar to the criteria 
referred to in this final rule as the ``Middle Tier'' CIU criteria) to 
its CIUs. For more information, refer to EPA's website for the pilot 
project http://www.epa.gov/projectxl/mwrd/page1.htm. EPA notes that 
this project is no longer active due to intergovernmental issues.
    EPA has concluded that the basic approach suggested by the 
commenters in their second tier (referred to now as ``Middle Tier'' 
CIUs), and approved for use by the Metropolitan Water Reclamation 
District of Greater Chicago's Project XL initiative, has merit in its 
focus on reducing reporting, inspection, and monitoring requirements 
for CIUs contributing a very small fraction of the POTW's design flow 
and pollutant loading. However, while adopting the basic criteria for 
the second tier (now referred to as the ``Middle Tier''), EPA has 
decided to adopt a ceiling of 5,000 gpd as compared to the recommended 
10,000 gpd. EPA has concluded that the 5,000 gpd ceiling will provide 
significant streamlining while providing additional assurance that 
larger dischargers which may have significant potential to cause Pass 
Through or Interference will continue to receive full SIU oversight.
    In addition, EPA has added additional safeguards designed to ensure 
the selection of appropriate CIUs and the proper documentation of data 
supporting the inclusion of individual CIUs in the Middle Tier. For 
instance, new 40 CFR 403.12(e)(3)(iii) binds the Control Authority's 
discretion by requiring eligible CIUs to ``not have daily flow rates, 
production levels, or pollutant levels that vary so significantly that 
decreasing the reporting requirement for this Industrial User would 
result in data that are not representative of conditions occurring 
during the reporting period pursuant to paragraph (g)(3) of this 
section.'' In addition, EPA specifies that any documentation supporting 
the Control Authority's finding that a specific CIU fits the Middle 
Tier criteria must be retained for a period of three years after the 
expiration of the term of the affected CIU's control mechanism. See 40 
CFR 403.12(e)(3)(v).
    How should the Control Authority develop its site-specific Middle 
Tier criteria? The criteria in 40 CFR 403.12(e)(3)(i) must first be 
translated into thresholds that are meaningful for the specific POTW. 
Each site-specific threshold will then be used to determine whether 
individual CIUs qualify for Middle Tier status. To complete the 
necessary calculations, the Control Authority will need to have the 
following information:
    <bullet> The POTW's design dry weather hydraulic treatment 
capacity: These

[[Page 60181]]

values, typically expressed in units of millions of gallons per day, 
are generally found in the POTW's design and specifications documents, 
and in many cases are identified in its NPDES Permit or Fact Sheet.
    <bullet> The POTW's design dry weather organic treatment capacity: 
These values, typically expressed as pounds per day, are also generally 
found in the POTW's design and specifications documents, and Operations 
and Maintenance manuals. Biochemical Oxygen Demand (BOD) measurements 
are used as a measure of the organic strength of wastes in wastewater. 
The Control Authority must use the design organic treatment capacity 
value that has been documented in their records for use in translating 
to useable thresholds for the Middle Tier CIUs.
    <bullet> The MAHL (Maximum Allowable Headworks Loading) for any 
pollutant for which approved local limits were developed by the POTW: 
The MAHL for each pollutant will be found in the POTW's approved 
technically based local limits supporting document and may also be 
identified in the POTW's local sewer use ordinance. EPA notes that a 
MAHL for a pollutant is not the same thing as the local limit for that 
pollutant. An MAHL is an estimate of the upper limit of pollutant 
loading to a POTW, intended to prevent Pass Through or Interference. 
MAHLs are the building blocks for local limits, as distinct from a 
local limit which is an allocation of the industrial portion of the 
headworks loading (MAHL) specific to one or more Industrial Users. 
Therefore, the Middle Tier criterion relating to MAHL is calculated as 
a percentage of the MAHL, not a percentage of a local limit. For 
additional information regarding the development of MAHLs and local 
limits, refer to Local Limits Development Guidance (EPA 833-R-04-002A, 
July 2004).
    Once the Control Authority has located this information, it will 
then need to multiply each value by 0.01% to translate those numbers 
into the criteria to be used to determine whether individual CIUs are 
eligible for Middle Tier status. Where the design hydraulic treatment 
capacity is concerned, if the product of 0.01 percent and the hydraulic 
capacity exceeds 5,000 gpd, then the regulations require the Control 
Authority to use the smaller number, or in this case 5,000 gpd.
    In addition, EPA recommends that the Control Authority list out the 
applicable Middle Tier eligibility criteria in the Industrial User's 
control mechanism. This will ensure that the CIU is specifically aware 
that its Middle Tier status only applies as long as it meets the 
eligibility criteria.
    How will Control Authorities determine if a specific Industrial 
User is eligible for Middle Tier status? EPA recommends that the 
initial determination of whether or not an Industrial User is eligible 
be made by comparing the User's actual Discharge (in units of flow or 
mass loading depending on the specific criterion) for the previous two 
years to each of the criterion to verify that the industry meets all of 
the criteria on a consistent basis. EPA notes that CIUs are required to 
establish eligibility by measuring their flow through the use of a 
continuous effluent flow monitor. See 40 CFR 403.12(e)(3)(i)(A). 
However, recognizing that continuous flow monitors are not appropriate 
for use in batch Discharges, the final rule provides an exception for 
those CIUs that discharge by batch. In such circumstances, EPA 
recommends that the batch discharger provide some other similarly 
accurate measure of flow, such as by providing a reasonable estimate of 
actual volume discharged from process wastewater containers.
    What documentation is required to designate Middle Tier CIUs? The 
Control Authority is required to document the specific criteria used in 
determining whether specific Industrial Users are considered Middle 
Tier CIUs. This documentation should show: (1) The translation of the 
40 CFR 403.12(e)(3)(i)(A)-(C) criteria into values that are specific to 
each Control Authority, and (2) the basis for including specific CIUs 
in the Middle Tier category. This information must be retained for a 
period of three years after the expiration of the term of the control 
mechanism. See 40 CFR 403.12(e)(3)(iv).
    Industrial Users will also need to retain sufficient information to 
verify that they continue to be eligible for Middle Tier CIU status, 
such as records showing their daily flows of categorical wastewater. 
The Control Authority (and Approval Authority in some instances) will 
use this information to validate the inclusion of Industrial Users in 
the Middle Tier CIU category. Industrial Users will find it necessary 
to have records of daily flows to be able to provide notification to 
the Control Authority if they exceed the flow criteria in 40 CFR 
403.12(e)(3)(i)(A).
    How often would an individual POTW's Middle Tier criteria be 
expected to change? It is not anticipated that the values upon which an 
individual POTW assigns Middle Tier status would change during the term 
of the POTW's NPDES control mechanism. Some scenarios which may 
necessitate a change to the POTW's Middle Tier criteria are:
    <bullet> Operations and maintenance work to correct excessive 
inflow and infiltration in the collection system: Where such changes 
affect actual wastewater flow, the POTW's local limits may need to be 
adjusted to account for this capacity change, thereby affecting the 
calculation of the plant's maximum allowable headworks loading (MAHL). 
Such adjustments to the MAHL may necessitate a recalculation of the 
POTW's Middle Tier criteria, which in turn may affect which CIUs are 
eligible for inclusion.
    <bullet> Collection System Expansions or Extensions/Treatment Plant 
Upgrades: Such modifications typically are conducted over a period of 
time and the effect on the treatment capability or efficiency of the 
POTW may not be instantaneously realized. When such improvements are 
completed, the Middle Tier criteria may need to be modified accordingly 
to reflect the new hydraulic and organic treatment capacities, as well 
as the MAHL. EPA notes that these situations are each identified in the 
Agency's local limits guidance as reasons to re-evaluate a POTW's local 
limits. See Chapter 7 of Local Limits Development Guidance (EPA 833-R-
04-002A, July 2004). EPA's guidance (page 7-5) indicates ``usually, a 
POTW will undertake a detailed reevaluation of its local limits in 
response to one of more significant changes at the treatment works or 
in the Discharges it receives. Recalculating existing MAHLs or 
determining MAHLs for new [pollutants of concern] is generally an 
appropriate response to changes in: Removal efficiencies; Total POTW or 
[Industrial User] loading; Limiting criteria (NPDES Permits, water 
quality standards, sludge criteria); Sludge characteristics or method 
of disposal (e.g., percent solids, disposal site life); Background 
concentrations of pollutants in receiving water.'' In addition, 
treatment efficiencies are verified annually, when the POTW submits its 
annual report, to the Approval Authority, which summarizes the changes 
within the Control Authority's Pretreatment program over the past year.
    <bullet> Local Limits Reevaluations: Formal reevaluations of a 
POTW's technically based local limits must be conducted with each 
renewal of the POTW's NPDES Permit. See 40 CFR 122.21(j)(2)(ii) EPA 
recommends, therefore, that recalculation of the Middles Tier criteria 
be performed and coordinated for submittal to the Approval Authority at 
the same time as the periodic local limits reevaluation,

[[Page 60182]]

easing the burden of separate reviews for both the Approval and Control 
Authorities.
    EPA notes that in situations where the Middle Tier criteria are 
modified, the Control Authority must submit the revised criteria to the 
Approval Authority as a modification to the POTW Pretreatment Program. 
Depending on the specific situation, Approval Authorities will 
determine whether a modification is a substantial or non-substantial 
modification of the approved Pretreatment Program. In either case, at a 
minimum, such modifications must be submitted to the Approval Authority 
by the Control Authority at least 45 days prior to implementation 
pursuant to 40 CFR 403.18.
    What criteria should a Control Authority apply if the Approved POTW 
Pretreatment Program involves more than one treatment plant? Similar to 
guidance provided in page 9-2 of the Local Limits Development Guidance 
(EPA 833-R-04-002A, July 2004), the Control Authority has options for 
how it applies or allocates its MAHLs. The Control Authority could 
decide to provide local limits to the Industrial Users based on the 
evaluation for the individual treatment works which serve those Users. 
Alternatively, the Control Authority could select the lowest (most 
stringent) local limit for each pollutant across all of the treatment 
plants. When establishing the Middle Tier criteria, the Control 
Authority can either apply the MAHL on a per POTW Treatment plant basis 
to only those IUs serviced by the individual treatment works, or it 
could identify and use the most stringent MAHL across all of its 
treatment plants.
    What happens if the CIU, after becoming eligible for Middle Tier 
status, exceeds the Middle Tier criteria? As stated previously, the 
CIU's eligibility for Middle Tier status depends on its ability to meet 
all of the criteria in 40 CFR 403.12(e)(3). If for any reason, a Middle 
Tier CIU finds that it no longer meets the conditions in 40 CFR 
403.12(e)(3)(i), (ii), or (iii), the CIU must notify the Control 
Authority and must immediately begin complying with the full SIU 
reporting requirements in 40 CFR 403.12(e)(1). For example, if a CIU 
exceeds its eligibility criterion for flow on any day as determined by 
its continuous effluent flow monitor, that User no longer meets the 
conditions for Middle Tier status, and must immediately notify the 
Control Authority and begin complying with the non-reduced frequency of 
SIU reporting requirements. Although not specified in the Middle Tier 
provisions, EPA recommends that Control Authorities consider whether 
they should preclude those CIUs which lose their Middle Tier status 
from regaining that status for at least the remainder of the term of 
the control mechanism. Where the Industrial User can demonstrate its 
ability to once again meet the eligibility conditions after sufficient 
passage of time (e.g., the remainder of the term of the control 
mechanism), the Control Authority may then consider renewing the User's 
status as a Middle Tier CIU.
    What type of oversight will EPA provide over the implementation of 
the Middle Tier CIU provisions? As with any new regulatory provision, 
given the number of conditions involved in the Middle Tier CIU 
category, EPA expects that the Agency will need to ensure that these 
provisions are implemented as intended. EPA will pay close attention to 
the Control Authority's adherence to these eligibility conditions and 
the overall implementation of these provisions. POTW Pretreatment 
Program audits and Pretreatment Compliance Inspections (PCIs) will 
provide EPA, as well as state Approval Authorities, with important 
opportunities to assess how the Control Authorities' are implementing 
this measure. Like any implementation issue in the Pretreatment 
Program, if a Control Authority has incorrectly applied the eligibility 
conditions such that one or several Industrial Users are erroneously 
considered Middle Tier CIUs, EPA will recommend in its audit or PCI 
findings that the Middle Tier status be revoked for those Users.
4. Summary of Major Comments and EPA Response
    Should EPA establish an NSCIU category? The overwhelming majority 
of commenters supported the proposed establishment of the NSCIU 
category, although many differed on what flow threshold would be the 
most appropriate for identifying such Industrial Users. One commenter 
expressed strong opposition to the creating the NSCIU category. This 
commenter indicated that EPA had not shown a basis in the record for 
this regulatory change, any evidence that the facilities and Control 
Authorities to be given streamlined oversight actually comply with 
applicable requirements, any evidence that Control Authorities will be 
able to detect noncompliance in a timely fashion without these 
oversight requirements, and any evidence that the change adequately 
protects POTWs and the environment. As outlined above, EPA is today 
finalizing provisions which enable Control Authorities to designate 
certain Categorical Industrial Users as NSCIUs, at their discretion, if 
the facilities meet all of the eligibility conditions, including 
discharging fewer than 100 gpd of total categorical wastewater.
    EPA disagrees with the commenter's rationale for opposing the 
establishment of the NSCIU category and the opportunity to reduce 
oversight for such Users. First, there is a basis in the record for 
this regulatory change. In the preamble to the proposed rule, EPA 
discussed the concerns of Control Authorities which supported the need 
for the proposal. Such concerns included the widely held perception 
that SIU oversight requirements are rigid, ``especially with respect to 
smaller facilities that are subject to categorical Pretreatment 
Standards and facilities that they believe have no potential to cause 
Pass Through or Interference.'' See 64 FR 39572 (July 22, 1999). EPA 
sought comment on the concept of allowing the Control Authority to 
identify Users as NSCIUs where they discharged fewer than 100 gpd, and 
to reduce the oversight required for such non-significant facilities. 
EPA provided an estimate of the percentage of CIUs that might be 
affected (1-2 percent), and has since projected that this number may be 
as high as 15 percent. Because these facilities will need to be good 
actors to be eligible (e.g., the regulations require a record of 
consistent compliance and annual certification of compliance with 
applicable Standards and Requirements), and because they individually 
contribute an insignificant amount of flow to the POTW, the Agency has 
concluded that it has an adequate basis for allowing Control 
Authorities to reduce oversight requirements for such facilities.
    Second, although EPA agrees that an Industrial User's compliance is 
a critical factor in whether the Control Authority may treat the User 
as an NSCIU, the Agency has concluded that it is unnecessary to 
evaluate overall compliance among these small CIUs prior to finalizing 
these provisions. What EPA is establishing in the final rule is the 
discretionary ability for Control Authorities to reduce oversight for 
select small Users. EPA is not requiring that this optional authority 
be used for any specific Industrial Users or that it be used in all 
cases. In fact, EPA would expect that the Control Authority will be 
reluctant to designate any particular CIU as an NSCIU if it has any 
concerns about the potential for any particular CIU to affect adversely 
the POTW or receiving water. Thus, the final rule requires, as a 
condition of eligibility for designation, that an Industrial User has a 
record of consistent compliance with applicable

[[Page 60183]]

Pretreatment Standards and Requirements prior to being defined as an 
NSCIU. See 40 CFR 403.3(v)(2)(i). After becoming an NSCIU, the User is 
then required to annually certify that it meets the definition of 
``non-Significant Categorical Industrial User'' and that it has 
complied with all applicable Pretreatment Standards and Requirements. 
See 40 CFR 403.12(q). With these safeguards in place, EPA concludes 
that the final rule addresses the commenter's concern about the lack of 
evidence on overall compliance.
    Third, EPA does not agree with the commenter's argument that 
Control Authorities will not have sufficient information to detect 
noncompliance in a timely fashion. It should be noted that the NSCIU 
provisions do not compel the Control Authority to reduce or eliminate 
applicable reporting, monitoring, and inspection requirements for every 
CIU with non-significant status. In fact, EPA expects that the Control 
Authority should assess each NSCIU to determine the extent to which 
oversight should be reduced. In addition, the combination of the NSCIU 
provisions and other existing regulatory requirements provide 
mechanisms for timely detection of noncompliance. Each Industrial User 
qualifying for NSCIU status must first demonstrate that it has 
consistently complied with applicable Pretreatment Standards and 
Requirements. After becoming an NSCIU, the User must annually certify 
that it still meets the requirements for non-significant status, and 
that it has complied with applicable Standards and Requirements. 
Lastly, as with all Industrial Users, the NSCIU is affected by the 
notification requirement in 40 CFR 403.12(j), which requires facilities 
to ``promptly notify the Control Authority (and the POTW if the POTW is 
not the Control Authority) in advance of any substantial change in the 
volume or character of pollutants in their Discharge * * *.'' And, each 
NSCIU must also comply with 40 CFR 403.12(f), which provides that ``all 
categorical * * * Industrial Users shall notify the POTW immediately of 
all Discharges that could cause problems to the POTW * * *.''
    Fourth, EPA has concluded that the NSCIU provisions will not affect 
protection of the POTW and the environment, contrary to the commenter's 
position. While the discretionary decision to treat an Industrial User 
as an NSCIU does relieve the Control Authority of certain oversight 
requirements with respect to the affected Industrial User, the 
facility's requirement to meet all applicable categorical Pretreatment 
Standards and its status as a CIU are not changed. Just because the CIU 
has been categorized as an NSCIU does not relieve it of its obligation 
to comply with categorical Pretreatment Standards and other applicable 
Pretreatment requirements, such as the notification provisions of 40 
CFR 403.12(f) and (j). Also, the NSCIU is required to annually certify 
that it has met applicable Pretreatment Standards and Requirements. 
Therefore, with these safeguards in place, EPA finds that the NSCIU 
provisions are fully protective of the POTW and the environment.
    How should the 100 gpd and Middle Tier criteria be applied to CIUs 
that commingle categorical and non-categorical wastestreams? Several 
commenters asserted that EPA should change the terms of the NSCIU 
language to indicate that only categorical wastestreams should be 
included when assessing whether an individual CIU meets the threshold 
for being designated as non-significant. EPA agrees, and has changed 
the definition of NSCIU to indicate that the CIU never discharges more 
than 100 gpd of ``total categorical wastewater.'' EPA finds it 
important to note that in many instances, all or most process 
wastewater discharged by NSCIUs will be categorical wastewater. And 
where facilities co-mingle different types of categorical wastewater, 
the threshold for determining whether or not a facility may be 
considered a non-significant CIU would be based on the total amount of 
categorical wastewater discharged. That is, the breakdown of 
categorical wastewater flows by industrial category would not affect 
the threshold determination. However, EPA recognizes that there may be 
cases where facilities discharge both categorical wastewater and non-
categorical process wastewater. This would occur where some of a 
facility's process wastewater Discharges were regulated under a 
National categorical Standard, while others were not, either because 
they were generated by operations from a different (non-regulated) 
industrial category, or because they were specifically excluded from 
coverage at the time the categorical Standards were promulgated. In 
cases where categorical and non-categorical process wastewater flow 
volumes cannot be reliably distinguished, the threshold determination 
should be based on total process wastewater flow volume.
    Middle Tier CIUs (discussed further below) also apply flow 
thresholds that are measured against an Industrial User's ``total 
categorical wastewater'' flow. EPA notes that the same approach for co-
mingled wastewater that applies to NSCIUs also applies to the Middle 
Tier CIUs.
    Do POTW's need to conduct annual inspections or sampling of NSCIUs? 
Several commenters recommended that EPA specifically reduce oversight 
of NSCIUs by limiting Control Authority inspections and/or sampling. 
The recommended frequencies ranged between every other year to as often 
as once-per-year. Other commenters supported completely eliminating 
inspection and sampling requirements. With the adoption of today's 
rule, EPA is not establishing any minimum inspection and sampling 
requirements for NSCIUs. Today's rule instead requires the Control 
Authority to perform an evaluation, at least once per year, on whether 
the NSCIU meets the criteria of 40 CFR 403.3(v)(2). As part of the 
annual evaluation, EPA recommends that the Control Authority conduct an 
on-site inspection of the facility in order to maintain awareness of 
the facility's process and to determine to the extent possible whether 
the discharger is complying with its Pretreatment Program requirements. 
As part of the evaluation, the Control Authority should verify the 
NSCIU's certification under 40 CFR 403.12(q) and review any other 
documentation provided by the facility. The level of effort devoted to 
an evaluation can be tailored to the facility. EPA again notes that it 
anticipates that this evaluation will primarily involve the Control 
Authority's verification that certification forms have been submitted 
by all NSCIUs documenting eligibility for NSCIU status and compliance 
with applicable Pretreatment Standards and Requirements. The Control 
Authority is not required to control the NSCIU through a Permit or 
other control mechanism. However, the Control Authority could, on a 
case by case basis, determine whether individual control mechanisms are 
necessary for NSCIUs and develop adequate sampling and inspection 
frequencies.
    One commenter suggested that some type of annual correspondence, at 
minimum, be incorporated into the Pretreatment Regulations to remind 
the NSCIU and Control Authority of their responsibilities and 
obligations under the Pretreatment Program. EPA agrees with the comment 
and has modified the rule language to include requirements that NSCIUs 
annually certify they are in compliance with all applicable 
Pretreatment Standards using the certification statement at 40 CFR 
403.12(q). Further, the Control Authority must perform an NSCIU 
evaluation, at least once per year, and provide an updated list of 
NSCIUs to the

[[Page 60184]]

Approval Authority as part of its annual POTW Pretreatment report.
    Can EPA provide some clarification of the NSCIU definition? 
Commenters expressed the need for clarification in the proposed 
definition of NSCIU. Several commenters were concerned that the 
language, as proposed, would allow Control Authorities to exempt a 
greater number of Industrial Users from Pretreatment Program 
requirements than what was intended under the proposal. These 
commenters interpreted the proposed definition to potentially allow an 
unlimited amount of treated concentrated wastewater (the proposal 
prohibited ``untreated concentrated wastes'') to be discharged to the 
POTW while still falling under the NSCIU threshold since it only 
required that Discharges of ``other process wastewater'' not be more 
than 100 gpd. Many commenters stated that a CIU could be deemed ``non-
significant'', under the proposed definition, if it could merely 
demonstrate that it did not discharge ``untreated concentrated wastes'' 
subject to the categorical Pretreatment Standards and not more than 100 
gpd of other process wastewater. Upon further consideration, EPA agrees 
that the proposed criteria for becoming a NSCIU was open to more than 
one interpretation and has revised the language in the final rule to 
further clarify the definition. Therefore, with the adoption of today's 
rule, EPA is clarifying the NSCIU definition to include ``100 gpd of 
total categorical wastewater'' in order to emphasize the fact that it 
is the ``total'' Discharge of 100 gpd or less of categorical process 
wastewater which qualifies a User for NSCIU status (as long as the 
other required conditions of 40 CFR 403.3(v)(2) are met), not some 
smaller subset of treated concentrated wastewaters.
    Why didn't EPA promulgate a higher flow threshold? Many commenters 
supported the concept of creating a flow cut-off threshold, but 
suggested that the 100 gpd ceiling was too low to provide any 
significant relief in burden. Commenters suggested alternative flow 
thresholds ranging from 300 gpd to 25,000 gpd, and also suggested that 
facilities that have little or no potential to impact the operation of 
the receiving POTW be included in this classification. Other POTW 
commenters supported the Association of Metropolitan Sewerage Agencies 
(AMSA, now renamed as the National Association of Clean Water Agencies) 
proposal of an alternative cutoff which would be specific to the POTW.
    EPA's intent in establishing the NSCIU category was to reduce the 
burden on Control Authorities of regulating Industrial Users which 
could truly be considered to present minimal impact to the treatment 
plant and the Pretreatment Program in general. It was not EPA's 
intention to remove a large segment of contributing CIUs from 
Pretreatment Program oversight, and the Agency has a limited amount of 
flow or other Discharge data from which to establish with any certainty 
the impact on the Pretreatment Program of allowing the NSCIU category 
to include a greater number of Users. EPA generally views the 100 gpd 
threshold as corresponding to the de minimis dischargers.
    In the proposal, EPA estimated that about 2 percent of the current 
CIUs might be eligible for non-significant status. A recent evaluation 
of 75 POTW Pretreatment Programs indicated that an average of 15 
percent of all CIUs in these municipalities would meet the 100 gpd 
threshold for NSCIU. EPA anticipates that the 100 gpd threshold will 
result in NSCIU eligibility for higher numbers of CIUs in select cities 
or regions.
    One commenter was opposed to any higher flow or narrative threshold 
for batch dischargers based on the fact that the proposal would have 
eliminated minimal, but critical, requirements for annual inspection 
and sampling, biennial slug control plan reviews, and permit reviews 
once every 5 years, while ignoring the compliance history and the 
discharger's potential to harm the POTW. EPA wishes to clarify that a 
Control Authority will have discretion to designate certain CIUs as 
NSCIUs if they meet specific criteria, and to exercise that discretion 
in the case of any individual CIUs, but will not be obligated to 
exercise this discretion in any particular case. Although certain 
facilities may be considered NSCIUs, EPA does not specify what types of 
reporting requirements are necessary. Although the Control Authority 
may choose a lesser amount of currently required sampling and 
reporting, the final rule does not mandate this decision. [As stated 
above, EPA does require that the Control Authority conduct at a minimum 
an annual evaluation.] EPA expects that this evaluation will primarily 
involve the Control Authority's verification that certification forms 
have been submitted by all NSCIUs documenting eligibility and 
compliance with Pretreatment Standards and Requirements. EPA has also 
created conditions that address the commenter's concern about facility 
compliance. For example, to be eligible for NSCIU status, a facility 
must have consistently complied with all applicable categorical 
Pretreatment Standards and Requirements prior to the Control 
Authority's findings. Further, the NSCIU must certify on an annual 
basis (per the certification requirement in 40 CFR 403.12(q)) that its 
Discharge is in compliance with all applicable categorical Standards 
and Requirements.
    May averaging be allowed in the NSCIU determination? EPA solicited 
comment on whether averaging should be allowed in determining whether a 
CIU fell under the 100 gpd threshold. Several commenters indicated that 
they concurred with the 100 gpd flow threshold, but suggested that the 
Agency include facilities that discharge up to 500 gallons per week. 
Today's final rule does not authorize the use of averaging to meet the 
100 gpd threshold. EPA is concerned that allowing such an approach 
could be difficult to oversee from the Control Authority's perspective, 
and could be burdensome to implement from the CIU's perspective. A 
greater degree of precision and a higher frequency of reporting would 
be needed to support a threshold that allows for an averaging of flow 
values. For instance, the CIU would need to record precise flow 
measurements every day to be able to determine whether its average 
discharge volume falls below the threshold, requiring the Industrial 
User to establish a more sophisticated approach for tracking the 
facility's Discharge. Also, the use of an averaging approach will make 
it harder for the Control Authority to be able to determine compliance 
on the days it conducts its inspections. Because the 100 gpd approach 
is applied as a threshold which cannot be exceeded, it can be 
implemented in a more straightforward manner which is expected to 
minimize the opportunity for misinterpretation. If a facility is a 
batch discharger and currently discharges more than 100 gpd, EPA 
recommends that the Industrial User install some form of flow 
restrictor that will ensure that its discharge of categorical process 
wastewater will never exceed 100 gallons on any single day.
    Does a facility have to treat its wastewater to be considered non-
significant? Several commenters expressed concern that it appeared from 
the proposal that a facility would need to install and provide 
treatment for all its wastewater prior to discharge. EPA clarifies that 
a facility does not need to have treatment in place in order to be 
considered non-significant, consistent with the fact that the 
categorical Standards do not dictate what types of treatment 
technologies the CIU must use so long as the facility's Discharge, with

[[Page 60185]]

or without treatment, remains in compliance with the categorical 
Standard. The Standards only provide the limits with which any 
Industrial User's Discharge must comply. On the other hand, the final 
NSCIU criteria require that the facility not discharge any ``untreated 
concentrated wastewater'' since it may be assumed that untreated 
concentrated wastewater (i.e., plating baths and rinses, solvents, 
sludges, etc.) would not be in compliance with the categorical 
Standard. Regardless of whether treatment exists at the CIU, the final 
rule requires that the facility must have consistently complied with 
all applicable categorical Pretreatment Standards and Requirements in 
order to be considered an NSCIU. Furthermore, the facility must, at 
minimum, annually certify that its Discharge is in compliance with all 
applicable categorical Pretreatment Standards and requirements.
    EPA should adopt a third tier of CIUs which provide further 
oversight flexibility based on the impact of the Industrial User on the 
specific POTW: As stated previously, eighteen (18) POTW commenters 
recommended that EPA adopt the following category of CIU in addition to 
the NSCIU and SIU categories:
    <bullet> The CIU's categorical wastewater Discharge does not exceed 
0.01 percent of the design dry weather hydraulic capacity of the 
receiving POTW, nor does it exceed 10,000 gpd;
    <bullet> The CIU's categorical wastewater Discharge does not exceed 
0.01 percent of the design dry weather organic treatment capacity of 
the receiving POTW;
    <bullet> The CIU's categorical wastewater Discharge does not exceed 
0.01 percent of the maximum allowable headworks loading (MAHL) for the 
receiving POTW of any pollutant detected at the POTW headworks for 
which the CIU is subject to a categorical Pretreatment Standard; and
    <bullet> The CIU has not been in significant noncompliance (SNC) 
for the most recent four consecutive six-month periods.
    As explained in Section III.K.3.b, EPA has included this basic 
approach in the final rule, with the exception of changing the volume 
ceiling from 10,000 gpd to 5,000 gpd.

IV. Description of Areas Where EPA Is Not Taking Action on the Proposed 
Rule

A. Specific Prohibition Regarding pH (40 CFR 403.5(b)(2))

    This section discusses EPA's proposal to amend 40 CFR 403.5(b)(2) 
to authorize the introduction of Discharges with pH less than 5.0 in 
certain circumstances. EPA has decided not to adopt the proposed 
changes to 40 CFR 403.5(b). EPA concluded that inadequate scientific 
information was available to determine the effects of short-term, low 
pH Discharges on the integrity of the POTW collection systems to 
support a change to the current prohibition on the introduction of 
Discharges with a pH lower than 5.0 into POTWs.
1. What is the existing rule?
    Acidic wastes can corrode sewer pipes with a resulting release of 
pollutants into the environment. To address this concern, the current 
regulations include a limit on the acidity of wastes, a minimum pH 
limit, in the specific prohibitions at 40 CFR 403.5(b). This 
prohibition applies to all nondomestic dischargers to POTWs. Section 
403.5(b)(2) prohibits the discharge of ``pollutants which will cause 
corrosive structural damage to the POTW, but in no case discharges with 
pH lower than 5.0, unless the works is specifically designed to 
accommodate such Discharges.''
2. What changes did EPA propose?
    EPA proposed to allow POTWs with Approved Pretreatment Programs to 
authorize temporary excursions below pH 5.0 provided that the POTW 
maintain a written technical evaluation supporting the finding that the 
alternative pH requirements did not have the potential to cause 
corrosive structural damage to the POTW or otherwise violate 40 CFR 
403.5(a) and (b). This change would have allowed POTWs to accept 
Discharges below pH 5.0 from Industrial Users that continuously 
monitored the pH of their Discharges, or to accept such temporary 
excursions by a limited group of Industrial Users. EPA proposed that 
any alternative pH requirement developed by a POTW would be enforceable 
as a Pretreatment Standard under the Clean Water Act. (The general 
narrative prohibition against pollutants that cause corrosive 
structural damage at 40 CFR 403.5(b)(2) would still have applied.)
3. What action is EPA taking today?
    EPA has decided not to adopt any changes to 40 CFR 403.5(b)(2). The 
existing specific prohibition against Discharges with pH lower than 5.0 
will remain in effect.
    In arriving at this decision, EPA has found that most of the 
current literature on the relationship between low pH and corrosion of 
sewer pipes is general and qualitative. References rarely address 
short-term Discharges of low pH and tend to only discuss effects of 
continuous exposure. Furthermore, predicting the effects of corrosion 
on POTW sewer pipes is complicated by a variety of factors, including 
wastewater characteristics such as pH, temperature, volume, velocity, 
turbulence, alkalinity, dissolved oxygen, as well as sewer pipe 
characteristics such as size, age, material of construction, pipe 
configuration, and time since last cleaning. EPA has concluded that 
insufficient research is available that investigates the synergistic 
effects of these factors as well as data on the effects of short-term 
Discharges of low pH and therefore modifications to the current 
regulations are not appropriate at this time.
What significant changes were made to the proposed rule?
    EPA has decided not to change the current rule regarding Discharges 
less than pH 5.0. EPA lacks sufficient information on the effects of 
short-term or long-term Discharges with pH lower than 5.0 on the 
structural integrity of POTWs. The current regulations at 40 CFR 
403.5(b) remain in effect.
4. Summary of Major Comments and EPA Response
    Many commenters gave qualified support for the proposed 
modifications with suggestions for implementation. EPA also received 
comments on the proposed rule stating that the proposal did not 
adequately protect POTWs. One commenter cautioned that systems 
constructed of acid-resistant materials often include manhole inverts 
constructed of concrete and similar materials that are susceptible to 
corrosion, and are thus rarely entirely resistant to such effects. Some 
requested that EPA make the current pH limit more stringent (i.e., 
above pH 5.0) because there are systems that are currently experiencing 
corrosion damage. A few commenters questioned whether the proposed 
modifications would actually provide a significant burden relief for 
POTWs, on the basis that adequate evidence does not exist that shows 
POTWs devote a substantial amount of resources to dealing with short-
term violations. Several commenters requested guidance on various 
implementation topics,

[[Page 60186]]

including how POTWs should assess and maintain the integrity of their 
systems with respect to corrosion. These outstanding issues influenced 
EPA's decision not to finalize the proposed modifications at this time.
    Even though EPA has decided not to finalize this proposed 
provision, all comments that were submitted on the proposal will be 
carefully considered as EPA further explores the issue of short-term pH 
Discharges. Please see the Response to Public Comment Document for 
responses to specific comments.
    Application of 40 CFR 401.17 Criteria: Some commenters suggested 
that the pH provisions at 40 CFR 401.17 could serve as a basis for 
alternative pH requirements. The effluent guideline regulations list 
certain conditions under which excursions from pH limits are allowed 
for direct dischargers. EPA developed 40 CFR 401.17 based on the 
Agency's determination that direct dischargers could continuously meet 
a pH limit between 6.0 and 9.0. In comparison, Pretreatment 
requirements are based on preventing corrosion in POTWs and are much 
less restrictive. It is EPA's view that it would be inappropriate to 
attempt to use 40 CFR 401.17 as a basis for alternative pH requirements 
because the reason behind establishing the pH requirement is different. 
However, POTWs may implement and enforce local pH limits in a manner 
that is more stringent than the federal regulations. EPA refers 
commenters to EPA's May 13, 1993 letter to Mary Jo M. Aiello of the New 
Jersey Department of Environmental Protection and Energy, for a 
discussion of an acceptable analogous application to the Pretreatment 
program. See http://www.epa.gov/npdes/pubs/owm0113.pdf.
    Use of Enforcement Response Plans to Address pH Violations: Several 
POTW commenters expressed concern over the level of burden imposed on 
them by the existing pH limit since they are obligated to treat all 
exceedances as violations. In EPA's view, it is relevant to clarify the 
inherent flexibility present in a POTW's Enforcement Response Plan 
provisions to define varying levels of response to temporary pH 
violations. EPA advises POTWs to incorporate a preferred method of 
dealing with violations of local limits into their Enforcement Response 
Plans and refers commenters to the Guidance for Developing Control 
Authority Enforcement Response Plans (EPA, 1989). See http://www.epa.gov/npdes/pubs/owm0015.pdf. EPA notes that POTWs make their own 
decisions regarding the utilization of resources in response to low pH 
Discharges when developing an Enforcement Response Plan. Excursions 
under pH 5.0 are Pretreatment Standard violations (40 CFR 403.5(b)(2)), 
and, in determining the appropriate response, EPA recommends that the 
Control Authority consider the following criteria: frequency, duration, 
magnitude, effect, and/or compliance. A record should be made of the 
response, and the person responsible for screening the data should 
alert enforcement personnel to the noncompliance. EPA recognizes that 
the Control Authority's appropriate response (including no further 
action, a phone call, or a notification letter) may vary. This 
flexibility may help reduce the burdens on the commenters' programs.

V. Changes to Part 122

    EPA is also making the following changes to the part 122 
regulations:
    <bullet> 40 CFR 122.21(j)(6)(ii): Change reference to definition of 
``Significant Industrial User'' to 40 CFR 403.3(v), instead of 40 CFR 
403.3(t). This reference change is a direct result of renumbering 
associated with today's rule.
    <bullet> 40 CFR 122.44(j)(1): Correct typographical error referring 
to ``significant indirect dischargers'' instead of the correct term, 
``Significant Industrial Users discharging''.
    <bullet> 40 CFR122.62(a)(7): Correct typographical error 
referencing an incorrect provision relating to modifications. The 
correct reference should be 40 CFR 403.18(e).

VI. Considerations in Adopting Today's Rule Revisions

How does a POTW adopt today's rule provisions?

    Section 40 CFR 403.18(a) generally requires review and approval by 
the Approval Authority of modifications to the POTW Pretreatment 
Program when there is a ``significant change in the operation of a POTW 
Pretreatment Program that differs from the information in the POTW's 
[program] submission * * * .'' Consistent with this rule, before many 
of today's streamlining provisions may be implemented by local 
Pretreatment authorities, POTWs will need to modify their Pretreatment 
Program procedures and authorities. Once the POTW has determined what 
program revisions it will make in response to today's streamlining 
provisions, the modifications must then be submitted to the Approval 
Authority (either the State, if it has Pretreatment Program authority, 
or the EPA Regional Administrator) for approval. The regulations also 
require that the program modification be accompanied by a statement of 
basis for the changes, a description of the modifications and other 
information the Approval Authority may request as appropriate. See 40 
CFR 403.18(c)(1).
    Although not required as part of today's final rule, EPA encourages 
a POTW to submit its Pretreatment Program modifications to its Approval 
Authority as a package, rather than sending changes piecemeal. This 
will help make the review process more efficient and less burdensome.

Is the POTW required to make any of today's streamlining changes?

    EPA notes that many of today's streamlining provisions are changes 
that the POTW may adopt at its discretion. Many of these changes (e.g., 
the authority to use general control mechanisms, monitoring waivers for 
pollutants neither present nor expected to be present, BMPs in lieu of 
numeric local limits, application of equivalent concentration limits in 
place of flow-based mass limits for OCPSF, petroleum refining, or 
pesticide chemicals facilities, creation of a category of non-
significant CIUs, and application of equivalent mass limits for 
concentration based categorical Standards) involve features that 
provide program flexibility and are not required to be incorporated 
into the POTW's Pretreatment Program.
    However, a few of today's rule provisions are changes that the POTW 
is required to make because they clarify certain minimum requirements, 
and to the extent that the POTW's approved program is inconsistent with 
these requirements, it would need to be modified. These required 
changes include:
    (1) 40 CFR 403.8(f)(1)(iii)(B)(6): Clarification that slug control 
requirements must be referenced in SIU control mechanisms. The POTW is 
required to adopt this change because it specifies new minimum 
requirements for all SIU control mechanisms.
    (2) 40 CFR 403.8(f)(2)(viii)(A)(B)(C): Revisions to the significant 
noncompliance (SNC) definition. These revisions are required because 
they expand the definition of SNC to include additional types of 
Pretreatment Standards and Requirements which were not clearly covered 
in previous definitions.
    (3) 40 CFR 403.12(g): Modifications to the sampling requirements 
and a clarification to the requirement to report all monitoring 
results. SIUs are now required to follow sampling requirements in 40 
CFR 403.12 for periodic compliance reports (40 CFR 403.12(e)), whereas 
they were

[[Page 60187]]

previously only explicitly applicable to baseline monitoring reports 
and 90-day compliance reports. Also, the final rule now requires that 
non-categorical SIUs report all monitoring results, whereas the 
previous regulations only made this requirement explicit for 
categorical SIUs. The POTW is required to adopt these revisions because 
they set new minimum requirements for sampling and notification.

What is the difference between a ``substantial modification'' and a 
``non-substantial'' modification?

    Different review procedures apply to program modifications 
depending on whether the modification is substantial or non-
substantial.
    The Approval Authority's review of a substantial modification, 
unlike a non-substantial modification, must follow the same procedures 
used for approving the initial POTW Pretreatment Program, including the 
issuance of a public notice to inform the public of the POTW's 
modification Submission. By contrast, where the Submission is reviewed 
as a non-substantial modification, the Approval Authority has 45 days 
to either approve or disapprove the modification. Where the Approval 
Authority does not notify the POTW within 45 days of its decision to 
approve or disapprove the modification, or to treat the modification as 
substantial, the POTW may implement the modification as if it were 
approved by the Approval Authority.

How will the POTW's adoption of today's streamlining provisions be 
reviewed by the Approval Authority?

    EPA has concluded that all of the changes related to today's rule 
may be treated as non-substantial if the changes to a POTW's local 
ordinance to incorporate the changes directly reflect the federal 
requirements. The current regulations provide that modifications that 
relax a POTW's legal authorities are substantial modifications ``except 
for modifications that directly reflect a revision to this Part 403 or 
to 40 CFR Chapter I, subchapter N, and are reported pursuant to 
paragraph (d) of this section.'' EPA has explained its reasons for 
adopting this provision as follows:
    <bullet> ``Today's regulation excludes from the definition of 
`substantial modification' those changes in POTW legal authority that 
results in less prescriptive programs, but which directly reflect a 
revision to Federal Pretreatment Regulations (for example, if the 
federal regulations are streamlined). 40 CFR 403.18(b)(1). Such 
modifications would have already undergone public notice and comment 
when promulgated by EPA. As long as the POTW's local ordinance is 
revised to directly reflect the new federal requirements, further 
public notice would be unnecessary * * *.'' 62 FR 38406, 38409 (July 
17, 1997).
    The Approval Authority, however, may treat such modifications as 
substantial when appropriate. 40 CFR 403.18(b)(7) authorizes the 
Approval Authority to designate modifications as substantial if the 
Approval Authority concludes that the modification could have a 
significant effect on POTW operation, could result in an increase in 
POTW pollutant loadings or could result in less stringent requirements 
being imposed on Industrial Users. For example, a POTW may wish to make 
adjustments to the wording of some of the streamlining provisions so 
that they fit better with the way the specific Pretreatment program is 
operated. Such adjustments may or may not trigger the need to review 
individual modifications as substantial, which would not otherwise need 
to be treated as substantial if today's provisions are adopted 
directly.
    Will the POTW's NPDES Permit need to be modified? In general, the 
Pretreatment provisions of the POTW's NPDES Permit will need to be 
modified. This regulatory action does not modify individual state 
regulations or authorities, POTW legal authorities, nor modify NPDES 
Permits issued to POTWs. Consequently, today's rule does not relieve a 
POTW from operating in accordance with existing state laws, 
regulations, Permits, and similar actions. If a POTW's Pretreatment 
program ``modification relates to an enforceable element of the POTW's 
NPDES Permit'', then the program ``modification requires a permit 
modification,'' in accordance with 40 CFR 403.8(c). 62 FR 38408 (July 
17, 1997). After a POTW's Pretreatment program modification has been 
approved in accordance with the procedures in 40 CFR 403.18, those 
conditions may be incorporated into the POTW's NPDES Permit as a minor 
NPDES modification under 40 CFR 122.63(g).

VII. Regulatory Requirements

A. Executive Order 12866: Regulatory Planning and Review

    Under Executive Order 12866, [58 Federal Register 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 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.
    Pursuant to the terms of Executive Order 12866, it has been 
determined that this rule is a ``significant regulatory action.'' As 
such, this action was submitted to OMB for review. Changes made in 
response to OMB suggestions or recommendations will be documented in 
the public record.

B. Paperwork Reduction Act

    The Office of Management and Budget (OMB) has approved the 
information collection requirements contained in this rule under the 
provisions of the Paperwork Reduction Act, 44 U.S.C. 3501 et seq. and 
has assigned OMB control number 2040-0009.
    The regulatory changes in today's rulemaking are designed to reduce 
the overall burden from technical and administrative requirements that 
affect Industrial Users, local Control Authorities and Approval 
Authorities. The estimated savings in annual burden hours and costs to 
the affected respondents (i.e., Industrial Users, POTWs, and States) is 
about 240,000 hours or $10.1 million.
    Burden means the total time, effort, or financial resources 
expended by persons to generate, maintain, retain, or disclose or 
provide information to or for a Federal agency. This includes the time 
needed to review instructions; develop, acquire, install, and utilize 
technology and systems for the purposes of collecting, validating, and 
verifying information, processing and maintaining information, and 
disclosing and providing information; adjust the existing ways to 
comply with any previously applicable instructions and requirements; 
train personnel to be able to respond to a collection of information; 
search data sources; complete and review the collection of information; 
and transmit or otherwise disclose the information.

[[Page 60188]]

    Although the regulatory changes in today's final rule provide 
greater flexibility to regulated entities, it is necessary to collect 
certain types of information to assure that Pretreatment Program 
requirements continue to be met and that the final benefit meets EPA's 
stated goal of providing better environmental results at less cost.
    Today's final rule includes regulatory changes that cover a variety 
of technical and administrative changes. Most of the regulatory changes 
result in either reduced annual cost and burdens on a continuing basis 
or have no measurable effect on cost or burden. There are a few 
regulatory changes (equivalent concentration limits for flow based 
Standards, monitoring waivers for pollutants not present, and general 
control mechanisms) that will impose additional short-term increases in 
burden on those POTWs or Industrial Users that elect to exercise this 
flexibility. However, when considered over a longer time period, these 
costs are outweighed by the expected benefits of the provisions.
    The table below (Table 1) shows an estimate of burden hours and 
cost savings for each rule provision.

                                                     Table 1.--Estimated Changes in Burden and Cost
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                             Total respondents
            Provision             ---------------------------------------    Change in total    Hours per  response    Annual responses      Change in
                                      States       POTWs         IUs      number of  responses                         per  respondent        burden
--------------------------------------------------------------------------------------------------------------------------------------------------------
Mass Limits......................  ...........           24           40  80 over 3 yrs.......  8..................  Varies.............             512
Equivalent Concentration Limits..  ...........        1,464  ...........  15..................  8.0................  0.01...............          122.67
NSCIUs/Middle-Tier CIUs..........           34        1,464        2,374  NA..................  See Note 1.........  Varies.............        -113,381
Slug Control Plans...............           34        1,464  ...........  -13,394.............  0.5................  1..................          -6,697
Pollutants Not Present--CIUs.....           34        1,464       12,362  NA..................  See Note 2.........  2..................        -117,703
General Control Mech's, Savings             34           20  ...........  1,500...............  -20.0..............  0.2................          -6,000
 for CAs.
General Control Mech's, Requests   ...........  ...........        1,500  1,500 over 3 yrs....  0.5................  One-Time...........             250
 for Coverage.
General Control Mech's, CA Use of           34           20  ...........  1,500 over 3 yrs....  0.5................  One-Time...........             250
 Data.
                                  --------------
    Total........................           34        1,464       12,362  ....................  ...................  ...................       -242,645
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note 1: For 34 states, the annual number of responses for permit issuance (20 hrs) drops by 0.6 per state. For 34 states, the number of inspections per
  year (8 hours) drops by 4.6 per state. For 34 states, the number of CIUs sampled per year (15.2 hours) drops by 4.6 per state. For 34 states, the
  number of NSCIU evaluations (2 hours) increases by 3.0 per state. For 34 states, total hours for review of CIU monitoring reports drops by 424 hours
  per year. For 1,464 POTWs, the annual number of responses for permit issuance (20 hrs) drops by 0.15 per POTW. For 1,464 POTWs, the number of
  inspections per year (8 hours) drops by 1.1 per POTW. For 1,464 POTWs, the number of CIUs sampled per year (16.2 hours) drops by 1.1 per POTW. For
  1,464 POTWs, the number of NSCIU evaluations (2 hours) rises from 0 to 0.73 per POTW. POTW burden for review of CIU monitoring reports drops a total
  of 8,664 hours. In addition, 796 CIUs reduce sampling and analysis (15.6 hours) from twice per year to never, 372 CIUs reduce sampling and analysis
  from twice per year to once every 5 years, and 1,206 CIUs reduce monitoring from twice to once per year. Also, 2,374 CIUs reduce reporting (1 hour)
  from twice to once per year. IU recordkeeping is eliminated for 1,168 IUs, saving 2337 hours (2 hrs per IU) per year; state recordkeeping decreases by
  513 hours per year. POTW recordkeeping is assumed to be unchanged.
Note 2: Hours per response drops from 18.8 to 15.2 for states, 10.0 to 8.1 for POTWs, and 14.3 to 11.6 for CIUs.

    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 in 40 CFR are listed in 40 CFR part 9. In addition, EPA is 
amending the table in 40 CFR part 9 of currently approved OMB control 
numbers for various regulations to list the regulatory citations for 
the information requirements contained in this final rule.

C. Regulatory Flexibility Act

    The Regulatory Flexibility Act (RFA) generally requires an agency 
to prepare a regulatory flexibility analysis of any rule subject to 
notice and comment rulemaking requirements under the Administrative 
Procedure Act or any other statute unless the agency certifies that the 
rule will not have a significant economic impact on a substantial 
number of small entities. Small entities include small businesses, 
small organizations, and small governmental jurisdictions.
    For purposes of assessing the impacts of today's rule on small 
entities, small entity is defined as: (1) A small business according to 
RFA default definitions for small business (based on SBA size standard; 
(2) a small governmental jurisdiction that is a government of a city, 
county, town, school district or special district with a population of 
less than 50,000; and (3) a small organization that is any not-for-
profit enterprise which is independently owned and operated and is not 
dominant in its field.
    After considering the economic impacts of today's final rule on 
small entities, I certify that this action will not have a significant 
economic impact on a substantial number of small entities. In 
determining whether a rule has a significant economic impact on a 
substantial number of small entities, the impact of concern is any 
significant adverse economic impact on small entities, since the 
primary purpose of the regulatory flexibility analyses is to identify 
and address regulatory alternatives ``which minimize any significant 
economic impact of the rule on small entities.'' 5 U.S.C. 603 and 604. 
Thus, an agency may certify that a rule will not have a significant 
economic impact on a substantial number of small entities if the rule 
relieves regulatory burden, or otherwise has a positive economic effect 
on all of the small entities subject to the rule.
    As previously explained, the modifications to the Pretreatment 
requirements in this final rule will reduce the regulatory costs to 
POTWs and Industrial Users of complying with Pretreatment requirements. 
The regulatory changes will provide certain POTWs and Industrial Users 
with less costly alternatives to the current requirements. For example, 
this rule includes a modification that would allow a POTW, in specified

[[Page 60189]]

circumstances, to control contributions from Industrial Users through 
general permits or control mechanisms rather than more costly 
individual permits or control mechanisms. This rule also authorizes a 
POTW to relieve an Industrial User of its sampling and analyzing 
requirements if the User demonstrates and certifies that the pollutant 
is neither present nor expected to be present in its process waste 
stream or is present only in background levels in the intake water.
    The final rule includes provisions that provide flexibility for 
POTWs and Industrial Users. For instance, POTWs will be allowed to use 
Best Management Practices (BMPs) as local limits in lieu of numeric 
effluent limits. This option will give POTWs a feasible alternative 
when numeric local limits are not the appropriate or practical method 
to prevent pollutant Pass Through or Interference. EPA does not expect 
that any POTW or Industrial User will choose the voluntary regulatory 
requirements over current requirements if the cost of the alternative 
were greater than the cost of complying with current regulations. We 
have therefore concluded that today's final rule will either relieve 
regulatory burden or have no significant impact for all small entities.

D. Unfunded Mandates Reform Act

    Title II of the Unfunded Mandates Reform Act of 1995 (UMRA), P.L. 
104-4, establishes requirements for Federal agencies to assess the 
effects of their regulatory actions on State, local, and tribal 
governments and the private sector. Under section 202 of the UMRA, EPA 
generally must prepare a written statement, including a cost-benefit 
analysis, for proposed and final rules with ``Federal mandates'' that 
may result in expenditures to State, local, and tribal governments, in 
the aggregate, or to the private sector, of $100 million or more in any 
one year. Before promulgating an EPA rule for which a written statement 
is needed, section 205 of the UMRA generally requires EPA to identify 
and consider a reasonable number of regulatory alternatives and adopt 
the least costly, most cost-effective or least burdensome alternative 
that achieves the objectives of the rule. The provisions of section 205 
do not apply when they are inconsistent with applicable law. Moreover, 
section 205 allows EPA to adopt an alternative other than the least 
costly, most cost-effective or least burdensome alternative if the 
Administrator publishes with the final rule an explanation why that 
alternative was not adopted.
    Before EPA establishes any regulatory requirements that may 
significantly or uniquely affect small governments, including tribal 
governments, it must have developed under section 203 of the UMRA a 
small government agency plan. The plan must provide for notifying 
potentially affected small governments, enabling officials of affected 
small governments to have meaningful and timely input in the 
development of EPA regulatory proposals with significant Federal 
intergovernmental mandates, and informing, educating, and advising 
small governments on compliance with the regulatory requirements.
    EPA has determined that this rule does not contain 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. Today's final rule is ``deregulatory'' in 
nature and reduces burden on the affected State, local, and tribal 
governments and the private sector. Thus, today's rule is not subject 
to the requirements of sections 202 and 205 of the UMRA.
    EPA has determined that this rule contains no regulatory 
requirements that might significantly or uniquely affect small 
governments. Additional flexibility is granted to all POTWs, which will 
provide opportunities for reducing the burden of administering their 
Pretreatment programs.

E. Executive Order 13132: Federalism

    Executive Order 13132, entitled ``Federalism'' (64 FR 43255, August 
10, 1999), requires EPA to develop an accountable process to ensure 
``meaningful and timely input by State and local officials in the 
development of regulatory policies that have federalism implications.'' 
``Policies that have federalism implications'' is defined in the 
Executive Order to include regulations that have ``substantial direct 
effects on the States, on the relationship between the national 
government and the States, or on the distribution of power and 
responsibilities among the various levels of government.''
    This final rule does not have federalism implications. It will not 
have substantial direct effects on the States, on the relationship 
between the national government and the States, or on the distribution 
of power and responsibilities among the various levels of government, 
as specified in Executive Order 13132. Today's rule is basically 
deregulatory in nature and is expected to reduce administrative and 
resource burdens on affected State, local, and tribal governments and 
the private sector. Thus, Executive Order 13132 does not apply to this 
rule.
    Although section 6 of Executive Order 13132 does not apply to this 
rule, EPA did consult with representatives of State and local officials 
in developing this rule. Annual EPA/State National Pretreatment 
Workshops have provided the opportunity for EPA and States to discuss 
current technical and policy issues as well as the future direction of 
the National Pretreatment Program. Representatives of EPA, States, and 
local Pretreatment programs have also convened annually at the 
Association of Metropolitan Sewerage Agencies' (AMSA's) Pretreatment 
Workshop. In the spirit of Executive Order 13132, and consistent with 
EPA policy to promote communication between EPA and State and local 
governments, EPA solicited comment on the proposed rule from all 
stakeholders. A summary of EPA's response to concerns raised is 
provided in Sections III and IV of the preamble (see specifically 
subsections entitled ``Summary of Major Comments and EPA Response'' for 
each separate streamlining issue) and in the response to comment 
document in the record.

F. Executive Order 13175: Consultation and Coordination With Indian 
Tribal Governments

    Executive Order 13175, entitled ``Consultation and Coordination 
with Indian Tribal Governments'' (65 FR 67249, November 6, 2000), 
requires EPA to develop an accountable process to ensure ``meaningful 
and timely input by tribal officials in the development of regulatory 
policies that have tribal implications.'' ``Policies that have tribal 
implications'' is defined in the Executive Order to include regulations 
that have ``substantial direct effects on one or more Indian tribes, on 
the relationship between the Federal government and the Indian tribes, 
or on the distribution of power and responsibilities between the 
Federal government and Indian tribes.''
    This final rule does not have tribal implications. It will not have 
substantial direct effects on tribal governments, on the relationship 
between the Federal government and Indian tribes, or on the 
distribution of power and responsibilities between the Federal 
government and Indian tribes, as specified in Executive Order 13175. 
There are no Pretreatment programs administered by Indian tribal 
governments. This final rule will neither ``significantly nor 
uniquely'' affect the communities of Indian tribal governments. Thus, 
Executive Order 13175 does not apply to this rule.

[[Page 60190]]

    Moreover, in the spirit of Executive Order 13175, and consistent 
with EPA policy to promote communications between EPA and tribal 
governments, EPA specifically solicited comment on the proposed rule 
from all stakeholders. EPA did not receive any comments from tribal 
governments.

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

    Executive Order 13045, ``Protection of Children from Environmental 
Health Risks and Safety Risks'' (62 FR 19885, April 23, 1997) applies 
to any rule that: (1) Is determined to be ``economically significant'' 
as defined under Executive Order 12866, and (2) concerns an 
environmental health or safety risk that EPA has reason to believe may 
have a disproportionate effect on children. If the regulatory action 
meets both criteria, the Agency must evaluate the environmental health 
or safety effects of the planned rule on children, and explain why the 
planned regulation is preferable to other potentially effective and 
reasonably feasible alternatives considered by the Agency.
    This final rule is not subject to the Executive Order because it is 
not economically significant as defined in Executive Order 12866, and 
because the Agency does not have reason to believe the environmental 
health or safety risks addressed by this action present a 
disproportionate risk to children. This final rule does not impose any 
new or amended Standards for discharged wastewater or the sludge 
resulting from treatment of a POTW. (EPA notes that the final rule does 
enable POTWs to use alternative, equivalent concentration limits for an 
industry's current flow-based mass Standards and equivalent mass limits 
where conditions warrant. However, EPA considers these new limits to be 
equivalent to the Standards previously used, and therefore does not 
involve the establishment of new or amended Standards.) Treatment and 
disposal of wastewater occurs in a restricted system (e.g., buried 
sewer lines and fenced wastewater treatment facilities) that children 
are unlikely to come in contact with on a routine basis. This rule has 
no identifiable direct impact upon the health and/or safety risks to 
children and the regulatory changes will not disproportionately affect 
children.

H. Executive Order 13211: Actions That Significantly Affect Energy 
Supply, Distribution, or Use

    This rule is not a ``significant energy action'' as defined in 
Executive Order 13211, ``Actions Concerning Regulations That 
Significantly Affect Energy Supply, Distribution, or Use'' (66 FR 28355 
(May 22, 2001)) because it is not likely to have a significant adverse 
effect on the supply, distribution, or use of energy. The final rule 
does not contain any compliance requirements that will:
    1. Reduce crude oil supply in excess of 10,000 barrels per day;
    2. Reduce fuel production in excess of 4,000 barrels per day;
    3. Reduce coal production in excess of 5 million tons per year;
    4. Reduce electricity production in excess of 1 billion kilowatt-
hours per year or in excess of 500 megawatts of installed capacity;
    5. Increase energy prices in excess of 10 percent;
    6. Increase the cost of energy distribution in excess of 10 
percent;
    7. Significantly increase dependence on foreign supplies of energy; 
or
    8. Other similar adverse outcomes, particularly unintended ones.
    Thus, EPA has concluded that this rule is not likely to have any 
adverse energy effects.

I. National Technology Transfer and Advancement Act

    As noted in the proposed rule, Section 12(d) of the National 
Technology Transfer and Advancement Act of 1995 (``NTTAA''), Public Law 
No. 104-113, 12(d) (15 U.S.C. 272 note) directs EPA to use voluntary 
consensus standards in its regulatory activities unless to do so would 
be inconsistent with applicable law or otherwise impractical. Voluntary 
consensus standards are technical standards (e.g., materials 
specifications, test methods, sampling procedures, and business 
practices) that are developed or adopted by voluntary consensus 
standards bodies. The NTTAA directs EPA to provide Congress, through 
OMB, explanations when the Agency decides not to use available and 
applicable voluntary consensus standards.
    This rule does not involve technical standards, except to the 
extent that various sampling procedures in the Pretreatment Regulations 
are being updated to reflect current EPA methods. Therefore, EPA did 
not consider the use of any voluntary consensus standards.

J. Congressional Review Act

    The Congressional Review Act, 5 U.S.C. 801 et seq., as added by the 
Small Business Regulatory Enforcement Fairness Act of 1996, generally 
provides that before a rule may take effect, the agency promulgating 
the rule must submit a rule report, which includes a copy of the rule, 
to each House of the Congress and to the Comptroller General of the 
United States. EPA will submit a report containing this rule and other 
required information to the U.S. Senate, the U.S. House of 
Representatives, and the Comptroller General of the United States prior 
to publication of the rule in the Federal Register. A Major rule cannot 
take effect until 60 days after it is published in the Federal 
Register. This action is not a ``major rule'' as defined by 5 U.S.C. 
804(2). This rule will be effective on November 14, 2005.

List of Subjects

40 CFR Part 9

    Environmental protection, Reporting and recordkeeping requirements.

40 CFR Part 122

    Environmental protection, Administrative practice and procedure, 
Confidential business information, Hazardous substances, Reporting and 
recordkeeping requirements, Water pollution control.

40 CFR Part 403

    Environmental protection, Confidential business information, 
Reporting and recordkeeping requirements, Waste treatment and disposal, 
Water pollution control.

    Dated: September 27, 2005.
Stephen L. Johnson,
Administrator.

0
For the reasons set out in the preamble, title 40, chapter I of the 
Code of Federal Regulations is amended as follows:

PART 9--OMB APPROVALS UNDER THE PAPERWORK REDUCTION ACT

0
1. The authority citation for part 9 continues to read as follows:

    Authority: 7 U.S.C. 135 et seq., 136-136y; 15 U.S.C. 2001, 2003, 
2005, 2006, 2601-2671, 21 U.S.C 331j, 356a, 348; 31 U.S.C. 9701; 33 
U.S.C. 1251 et seq., 1311, 1313d, 1314, 1318, 1321, 1326, 1330, 
1342, 1344, 1345 (d) and (e), 1361; E.O. 11735, 38 FR 21243, 3 CFR, 
1971-1975 Comp. p. 973; 42 U.S.C. 241, 242b, 243, 246, 300f, 300g, 
300g-1, 300g-2, 300g-3, 300g-4, 300g-5, 300g-6, 300j-1, 300j-2, 
300j-3, 300j-4, 300j-9, 1857 et seq., 6901-6992k, 7401-7671q, 7542, 
9601-9657, 11023, 11048.

    2. In Sec.  9.1 the table is amended by adding an entry in 
numerical order under the indicated heading to read as follows:


Sec.  9.1  OMB approvals under the Paper Work Reduction Act.

* * * * *

[[Page 60191]]



------------------------------------------------------------------------
                                                             OMB control
                      40 CFR citation                            No.
------------------------------------------------------------------------
    General Pretreatment Regulations for Existing and New Sources of
                                Pollution
------------------------------------------------------------------------
 
                             * *; * * * * *
403.12(q)..................................................    2040-0009
 
                               * * * * * *
------------------------------------------------------------------------

PART 122--EPA ADMINISTERED PERMIT PROGRAMS: THE NATIONAL POLLUTANT 
DISCHARGE ELIMINATION SYSTEM

0
3. The authority citation for Part 122 continues to read as follows:

    Authority: The Clean Water Act, 33 U.S.C. 1251 et seq.


0
4. Section 122.21 is amended by revising paragraph (j)(6)(ii) 
introductory text to read as follows:


Sec.  122.21  Application for a permit (applicable to State programs, 
see Sec.  123.25).

* * * * *
    (j) * * *
    (6) * * *
    (ii) POTWs with one or more SIUs shall provide the following 
information for each SIU, as defined at 40 CFR 403.3(v), that 
discharges to the POTW:
* * * * *


0
5. Section 122.44 is amended by revising the first sentence of 
paragraph (j)(1) to read as follows:


Sec.  122.44  Establishing limitations, standards, and other permit 
conditions (applicable to State NPDES programs, see Sec.  123.25).

* * * * *
    (j) * * *
    (1) Identify, in terms of character and volume of pollutants, any 
Significant Industrial Users discharging into the POTW subject to 
Pretreatment Standards under section 307(b) of CWA and 40 CFR part 403.
* * * * *


0
6. Section 122.62 is amended by revising paragraph (a)(7) to read as 
follows:


Sec.  122.62  Modification or revocation and reissuance of permits 
(applicable to State programs, see Sec.  123.25).

* * * * *
    (a) * * *
    (7) Reopener. When required by the ``reopener'' conditions in a 
permit, which are established in the permit under Sec.  122.44(b) (for 
CWA toxic effluent limitations and Standards for sewage sludge use or 
disposal, see also Sec.  122.44(c)) or 40 CFR 403.18(e) (Pretreatment 
program).
* * * * *

PART 403--GENERAL PRETREATMENT REGULATIONS FOR EXISTING AND NEW 
SOURCES OF POLLUTION

0
7. The authority for Part 403 continues to read as follows:

    Authority: 33 U.S.C. 1251 et seq.


0
8. Section 403.3 is amended by redesignating paragraphs (e) through (u) 
as paragraphs (g) through (w); by revising newly designated paragraphs 
(m)(2) and (v); and by adding new paragraphs (e) and (f) to read as 
follows:


Sec.  403.3.  Definitions.

* * * * *
    (e) The term Best Management Practices or BMPs means schedules of 
activities, prohibitions of practices, maintenance procedures, and 
other management practices to implement the prohibitions listed in 
Sec.  403.5(a)(1) and (b). BMPs also include treatment requirements, 
operating procedures, and practices to control plant site runoff, 
spillage or leaks, sludge or waste disposal, or drainage from raw 
materials storage.
    (f) The term Control Authority refers to:
    (1) The POTW if the POTW's Pretreatment Program Submission has been 
approved in accordance with the requirements of Sec.  403.11; or
    (2) The Approval Authority if the Submission has not been approved.
* * * * *
    (m) * * *
    (2) Construction on a site at which an existing source is located 
results in a modification rather than a New Source if the construction 
does not create a new building, structure, facility or installation 
meeting the criteria of paragraphs (m)(1)(ii) or (m)(1)(iii) of this 
section, but otherwise alters, replaces, or adds to existing process or 
production equipment.
* * * * *
    (v) Significant Industrial User. (1) Except as provided in 
paragraphs (v)(2) and (v)(3) of this section, the term Significant 
Industrial User means:
    (i) All Industrial Users subject to Categorical Pretreatment 
Standards under 40 CFR 403.6 and 40 CFR chapter I, subchapter N; and
    (ii) Any other Industrial User that: discharges an average of 
25,000 gallons per day or more of process wastewater to the POTW 
(excluding sanitary, noncontact cooling and boiler blowdown 
wastewater); contributes a process wastestream which makes up 5 percent 
or more of the average dry weather hydraulic or organic capacity of the 
POTW Treatment plant; or is designated as such by the Control Authority 
on the basis that the Industrial User has a reasonable potential for 
adversely affecting the POTW's operation or for violating any 
Pretreatment Standard or requirement (in accordance with 40 CFR 
403.8(f)(6)).
    (2) The Control Authority may determine that an Industrial User 
subject to categorical Pretreatment Standards under Sec.  403.6 and 40 
CFR chapter I, subchapter N is a Non-Significant Categorical Industrial 
User rather than a Significant Industrial User on a finding that the 
Industrial User never discharges more than 100 gallons per day (gpd) of 
total categorical wastewater (excluding sanitary, non-contact cooling 
and boiler blowdown wastewater, unless specifically included in the 
Pretreatment Standard) and the following conditions are met:
    (i) The Industrial User, prior to the Control Authority's finding, 
has consistently complied with all applicable categorical Pretreatment 
Standards and Requirements;
    (ii) The Industrial User annually submits the certification 
statement required in Sec.  403.12(q) together with any additional 
information necessary to support the certification statement; and
    (iii) The Industrial User never discharges any untreated 
concentrated wastewater.
    (3) Upon a finding that an Industrial User meeting the criteria in 
paragraph (v)(1)(ii) of this section has no reasonable potential for 
adversely affecting the POTW's operation or for violating any 
Pretreatment Standards or

[[Page 60192]]

requirement, the Control Authority may at any time, on its own 
initiative or in response to a petition received from an Industrial 
User or POTW, and in accordance with 40 CFR 403.8(f)(6), determine that 
such Industrial User is not a Significant Industrial User.
* * * * *

0
9. Section 403.5 is amended by revising paragraph (b)(1) and adding a 
new paragraph (c)(4) to read as follows:


Sec.  403.5  National pretreatment standards: Prohibited discharges.

* * * * *
    (b) * * *
    (1) Pollutants which create a fire or explosion hazard in the POTW, 
including, but not limited to, wastestreams with a closed cup 
flashpoint of less than 140 degrees Fahrenheit or 60 degrees Centigrade 
using the test methods specified in 40 CFR 261.21;
* * * * *
    (c) * * *
    (4) POTWs may develop Best Management Practices (BMPs) to implement 
paragraphs (c)(1) and (c)(2) of this section. Such BMPs shall be 
considered local limits and Pretreatment Standards for the purposes of 
this part and section 307(d) of the Act.
* * * * *


0
10. Section 403.6 is amended as follows:
0
a. By revising paragraph (b).
0
b. By revising paragraph (c)(2).
0
c. By redesignating paragraphs (c)(5) through (c)(7) as paragraphs 
(c)(7) through (c)(9).
0
d. By adding new paragraphs (c)(5) and (c)(6).
0
e. By revising newly designated paragraphs (c)(7) and (c)(8).
0
f. By revising paragraph (d), and the first sentence of paragraph (e) 
introductory text.


Sec.  403.6  National pretreatment standards: Categorical standards.

* * * * *
    (b) Deadline for compliance with categorical standards. Compliance 
by existing sources with categorical Pretreatment Standards shall be 
within 3 years of the date the Standard is effective unless a shorter 
compliance time is specified in the appropriate subpart of 40 CFR 
chapter I, subchapter N. Direct dischargers with NPDES Permits modified 
or reissued to provide a variance pursuant to section 301(i)(2) of the 
Act shall be required to meet compliance dates set in any applicable 
categorical Pretreatment Standard. Existing sources which become 
Industrial Users subsequent to promulgation of an applicable 
categorical Pretreatment Standard shall be considered existing 
Industrial Users except where such sources meet the definition of a New 
Source as defined in Sec.  403.3(m). New Sources shall install and have 
in operating condition, and shall ``start-up'' all pollution control 
equipment required to meet applicable Pretreatment Standards before 
beginning to Discharge. Within the shortest feasible time (not to 
exceed 90 days), New Sources must meet all applicable Pretreatment 
Standards.
    (c) * * *
    (2) When the limits in a categorical Pretreatment Standard are 
expressed only in terms of mass of pollutant per unit of production, 
the Control Authority may convert the limits to equivalent limitations 
expressed either as mass of pollutant discharged per day or effluent 
concentration for purposes of calculating effluent limitations 
applicable to individual Industrial Users.
* * * * *
    (5) When the limits in a categorical Pretreatment Standard are 
expressed only in terms of pollutant concentrations, an Industrial User 
may request that the Control Authority convert the limits to equivalent 
mass limits. The determination to convert concentration limits to mass 
limits is within the discretion of the Control Authority. The Control 
Authority may establish equivalent mass limits only if the Industrial 
User meets all the following conditions in paragraph (c)(5)(i)(A) 
through (c)(5)(i)(E) of this section.
    (i) To be eligible for equivalent mass limits, the Industrial User 
must:
    (A) Employ, or demonstrate that it will employ, water conservation 
methods and technologies that substantially reduce water use during the 
term of its control mechanism;
    (B) Currently use control and treatment technologies adequate to 
achieve compliance with the applicable categorical Pretreatment 
Standard, and not have used dilution as a substitute for treatment;
    (C) Provide sufficient information to establish the facility's 
actual average daily flow rate for all wastestreams, based on data from 
a continuous effluent flow monitoring device, as well as the facility's 
long-term average production rate. Both the actual average daily flow 
rate and long-term average production rate must be representative of 
current operating conditions;
    (D) Not have daily flow rates, production levels, or pollutant 
levels that vary so significantly that equivalent mass limits are not 
appropriate to control the Discharge; and
    (E) Have consistently complied with all applicable categorical 
Pretreatment Standards during the period prior to the Industrial User's 
request for equivalent mass limits.
    (ii) An Industrial User subject to equivalent mass limits must:
    (A) Maintain and effectively operate control and treatment 
technologies adequate to achieve compliance with the equivalent mass 
limits;
    (B) Continue to record the facility's flow rates through the use of 
a continuous effluent flow monitoring device;
    (C) Continue to record the facility's production rates and notify 
the Control Authority whenever production rates are expected to vary by 
more than 20 percent from its baseline production rates determined in 
paragraph (c)(5)(i)(C) of this section. Upon notification of a revised 
production rate, the Control Authority must reassess the equivalent 
mass limit and revise the limit as necessary to reflect changed 
conditions at the facility; and
    (D) Continue to employ the same or comparable water conservation 
methods and technologies as those implemented pursuant to paragraph 
(c)(5)(i)(A) of this section so long as it discharges under an 
equivalent mass limit.
    (iii) A Control Authority which chooses to establish equivalent 
mass limits:
    (A) Must calculate the equivalent mass limit by multiplying the 
actual average daily flow rate of the regulated process(es) of the 
Industrial User by the concentration-based daily maximum and monthly 
average Standard for the applicable categorical Pretreatment Standard 
and the appropriate unit conversion factor;
    (B) Upon notification of a revised production rate, must reassess 
the equivalent mass limit and recalculate the limit as necessary to 
reflect changed conditions at the facility; and
    (C) May retain the same equivalent mass limit in subsequent control 
mechanism terms if the Industrial User's actual average daily flow rate 
was reduced solely as a result of the implementation of water 
conservation methods and technologies, and the actual average daily 
flow rates used in the original calculation of the equivalent mass 
limit were not based on the use of dilution as a substitute for 
treatment pursuant to paragraph (d) of this section. The Industrial 
User must also be in compliance with Sec.  403.17 (regarding the 
prohibition of bypass).
    (iv) The Control Authority may not express limits in terms of mass 
for

[[Page 60193]]

pollutants such as pH, temperature, radiation, or other pollutants 
which cannot appropriately be expressed as mass.
    (6) The Control Authority may convert the mass limits of the 
categorical Pretreatment Standards at 40 CFR parts 414, 419, and 455 to 
concentration limits for purposes of calculating limitations applicable 
to individual Industrial Users under the following conditions. When 
converting such limits to concentration limits, the Control Authority 
must use the concentrations listed in the applicable subparts of 40 CFR 
parts 414, 419, and 455 and document that dilution is not being 
substituted for treatment as prohibited by paragraph (d) of this 
section.
    (7) Equivalent limitations calculated in accordance with paragraphs 
(c)(3), (c)(4), (c)(5) and (c)(6) of this section are deemed 
Pretreatment Standards for the purposes of section 307(d) of the Act 
and this part. The Control Authority must document how the equivalent 
limits were derived and make this information publicly available. Once 
incorporated into its control mechanism, the Industrial User must 
comply with the equivalent limitations in lieu of the promulgated 
categorical standards from which the equivalent limitations were 
derived.
    (8) Many categorical Pretreatment Standards specify one limit for 
calculating maximum daily discharge limitations and a second limit for 
calculating maximum monthly average, or 4-day average, limitations. 
Where such Standards are being applied, the same production or flow 
figure shall be used in calculating both the average and the maximum 
equivalent limitation.
* * * * *
    (d) Dilution prohibited as substitute for treatment. Except where 
expressly authorized to do so by an applicable Pretreatment Standard or 
Requirement, no Industrial User shall ever increase the use of process 
water, or in any other way attempt to dilute a Discharge as a partial 
or complete substitute for adequate treatment to achieve compliance 
with a Pretreatment Standard or Requirement. The Control Authority may 
impose mass limitations on Industrial Users which are using dilution to 
meet applicable Pretreatment Standards or Requirements, or in other 
cases where the imposition of mass limitations is appropriate.
    (e) Combined wastestream formula. Where process effluent is mixed 
prior to treatment with wastewaters other than those generated by the 
regulated process, fixed alternative discharge limits may be derived by 
the Control Authority or by the Industrial User with the written 
concurrence of the Control Authority. * * *
* * * * *

0
11. Section 403.7 is amended by revising paragraphs (h) introductory 
text and (h)(2) to read as follows:


Sec.  403.7  Removal credits.

* * * * *
    (h) Compensation for Overflow. ``Overflow'' means the intentional 
or unintentional diversion of flow from the POTW before the POTW 
Treatment Plant. POTWs which at least once annually Overflow untreated 
wastewater to receiving waters may claim Consistent Removal of a 
pollutant only by complying with either paragraphs (h)(1) or (h)(2) of 
this section. However, paragraph (h) of this section shall not apply 
where Industrial User(s) can demonstrate that Overflow does not occur 
between the Industrial User(s) and the POTW Treatment Plant;
* * * * *
    (2)(i) The Consistent Removal claimed is reduced pursuant to the 
following equation:
[GRAPHIC] [TIFF OMITTED] TR14OC05.000


Where:
r<INF>m</INF> = POTW's Consistent Removal rate for that pollutant as 
established under paragraphs (a)(1) and (b)(2) of this section
r<INF>c</INF> = removal corrected by the Overflow factor
Z = hours per year that Overflows occurred between the Industrial 
User(s) and the POTW Treatment Plant, the hours either to be shown in 
the POTW's current NPDES permit application or the hours, as 
demonstrated by verifiable techniques, that a particular Industrial 
User's Discharge Overflows between the Industrial User and the POTW 
Treatment Plant; and

    (ii) The POTW is complying with all NPDES permit requirements and 
any additional requirements in any order or decree, issued pursuant to 
the Clean Water Act affecting combined sewer overflows. These 
requirements include, but are not limited to, any combined sewer 
overflow requirements that conform to the Combined Sewer Overflow 
Control Policy.

0
12. Section 403.8 is amended as follows:
0
a. By revising paragraphs (f)(1)(iii), (f)(1)(v), and the first 
sentence of paragraph (f)(1)(vi)(B).
0
b. By revising paragraph (f)(2)(v).
0
c. By redesignating paragraphs (f)(2)(vi) and (f)(2)(vii) as paragraphs 
(f)(2)(vii) and (f)(2)(viii);
0
d. By adding a new paragraph (f)(2)(vi).
0
e. By revising newly designated paragraphs (f)(2)(viii) introductory 
text, (f)(2)(viii)(A), (f)(2)(viii)(B), (f)(2)(viii)(C), 
(f)(2)(viii)(F), and (f)(2)(viii)(H).
0
f. Revising paragraph (f)(6).


Sec.  403.8  Pretreatment Program Requirements: Development and 
implementation by POTW.

* * * * *
    (f) * * *
    (1) * * *
    (iii) Control through Permit, order, or similar means, the 
contribution to the POTW by each Industrial User to ensure compliance 
with applicable Pretreatment Standards and Requirements. In the case of 
Industrial Users identified as significant under Sec.  403.3(v), this 
control shall be achieved through individual permits or equivalent 
individual control mechanisms issued to each such User except as 
follows.
    (A)(1) At the discretion of the POTW, this control may include use 
of general control mechanisms if the following conditions are met. All 
of the facilities to be covered must:
    (i) Involve the same or substantially similar types of operations;
    (ii) Discharge the same types of wastes;
    (iii) Require the same effluent limitations;
    (iv) Require the same or similar monitoring; and
    (v) In the opinion of the POTW, are more appropriately controlled 
under a general control mechanism than under individual control 
mechanisms.
    (2) To be covered by the general control mechanism, the Significant 
Industrial User must file a written request for coverage that 
identifies its contact information, production processes, the types of 
wastes generated, the location for monitoring all wastes covered by the 
general control mechanism, any requests in accordance with Sec.  
403.12(e)(2) for a monitoring waiver for a pollutant neither present 
nor expected to be present in the Discharge, and any other information 
the POTW deems appropriate. A monitoring waiver for a pollutant neither 
present nor expected to be present in the Discharge is not effective in 
the general control mechanism until after the POTW has provided written 
notice to the Significant Industrial User that such a waiver request 
has been

[[Page 60194]]

granted in accordance with Sec.  403.12(e)(2). The POTW must retain a 
copy of the general control mechanism, documentation to support the 
POTW's determination that a specific Significant Industrial User meets 
the criteria in paragraphs (f)(1)(iii)(A)(1) through (5) of this 
section, and a copy of the User's written request for coverage for 3 
years after the expiration of the general control mechanism. A POTW may 
not control a Significant Industrial User through a general control 
mechanism where the facility is subject to production-based categorical 
Pretreatment Standards or categorical Pretreatment Standards expressed 
as mass of pollutant discharged per day or for Industrial Users whose 
limits are based on the Combined Wastestream Formula or Net/Gross 
calculations (Sec. Sec.  403.6(e) and 403.15).
    (B) Both individual and general control mechanisms must be 
enforceable and contain, at a minimum, the following conditions:
    (1) Statement of duration (in no case more than five years);
    (2) Statement of non-transferability without, at a minimum, prior 
notification to the POTW and provision of a copy of the existing 
control mechanism to the new owner or operator;
    (3) Effluent limits, including Best Management Practices, based on 
applicable general Pretreatment Standards in part 403 of this chapter, 
categorical Pretreatment Standards, local limits, and State and local 
law;
    (4) Self-monitoring, sampling, reporting, notification and 
recordkeeping requirements, including an identification of the 
pollutants to be monitored (including the process for seeking a waiver 
for a pollutant neither present nor expected to be present in the 
Discharge in accordance with Sec.  403.12(e)(2), or a specific waived 
pollutant in the case of an individual control mechanism), sampling 
location, sampling frequency, and sample type, based on the applicable 
general Pretreatment Standards in part 403 of this chapter, categorical 
Pretreatment Standards, local limits, and State and local law;
    (5) Statement of applicable civil and criminal penalties for 
violation of Pretreatment Standards and requirements, and any 
applicable compliance schedule. Such schedules may not extend the 
compliance date beyond applicable federal deadlines;
    (6) Requirements to control Slug Discharges, if determined by the 
POTW to be necessary.
* * * * *
    (v) Carry out all inspection, surveillance and monitoring 
procedures necessary to determine, independent of information supplied 
by Industrial Users, compliance or noncompliance with applicable 
Pretreatment Standards and Requirements by Industrial Users. 
Representatives of the POTW shall be authorized to enter any premises 
of any Industrial User in which a Discharge source or treatment system 
is located or in which records are required to be kept under Sec.  
403.12(o) to assure compliance with Pretreatment Standards. Such 
authority shall be at least as extensive as the authority provided 
under section 308 of the Act;
    (vi) * * *
    (B) Pretreatment requirements which will be enforced through the 
remedies set forth in paragraph (f)(1)(vi)(A) of this section, will 
include but not be limited to, the duty to allow or carry out 
inspections, entry, or monitoring activities; any rules, regulations, 
or orders issued by the POTW; any requirements set forth in control 
mechanisms issued by the POTW; or any reporting requirements imposed by 
the POTW or these regulations in this part. * * *
* * * * *
    (2) * * *
    (v) Randomly sample and analyze the effluent from Industrial Users 
and conduct surveillance activities in order to identify, independent 
of information supplied by Industrial Users, occasional and continuing 
noncompliance with Pretreatment Standards. Inspect and sample the 
effluent from each Significant Industrial User at least once a year, 
except as otherwise specified below:
    (A) Where the POTW has authorized the Industrial User subject to a 
categorical Pretreatment Standard to forego sampling of a pollutant 
regulated by a categorical Pretreatment Standard in accordance with 
Sec.  403.12(e)(3), the POTW must sample for the waived pollutant(s) at 
least once during the term of the Categorical Industrial User's control 
mechanism. In the event that the POTW subsequently determines that a 
waived pollutant is present or is expected to be present in the 
Industrial User's wastewater based on changes that occur in the User's 
operations, the POTW must immediately begin at least annual effluent 
monitoring of the User's Discharge and inspection.
    (B) Where the POTW has determined that an Industrial User meets the 
criteria for classification as a Non-Significant Categorical Industrial 
User, the POTW must evaluate, at least once per year, whether an 
Industrial User continues to meet the criteria in Sec.  403.3(v)(2).
    (C) In the case of Industrial Users subject to reduced reporting 
requirements under Sec.  403.12(e)(3), the POTW must randomly sample 
and analyze the effluent from Industrial Users and conduct inspections 
at least once every two years. If the Industrial User no longer meets 
the conditions for reduced reporting in Sec.  403.12(e)(3), the POTW 
must immediately begin sampling and inspecting the Industrial User at 
least once a year.
    (vi) Evaluate whether each such Significant Industrial User needs a 
plan or other action to control Slug Discharges. For Industrial Users 
identified as significant prior to November 14, 2005, this evaluation 
must have been conducted at least once by October 14, 2006; additional 
Significant Industrial Users must be evaluated within 1 year of being 
designated a Significant Industrial User. For purposes of this 
subsection, a Slug Discharge is any Discharge of a non-routine, 
episodic nature, including but not limited to an accidental spill or a 
non-customary batch Discharge, which has a reasonable potential to 
cause Interference or Pass Through, or in any other way violate the 
POTW's regulations, local limits or Permit conditions. The results of 
such activities shall be available to the Approval Authority upon 
request. Significant Industrial Users are required to notify the POTW 
immediately of any changes at its facility affecting potential for a 
Slug Discharge. If the POTW decides that a slug control plan is needed, 
the plan shall contain, at a minimum, the following elements:
    (A) Description of discharge practices, including non-routine batch 
Discharges;
    (B) Description of stored chemicals;
    (C) Procedures for immediately notifying the POTW of Slug 
Discharges, including any Discharge that would violate a prohibition 
under Sec.  403.5(b) with procedures for follow-up written notification 
within five days;
    (D) If necessary, procedures to prevent adverse impact from 
accidental spills, including inspection and maintenance of storage 
areas, handling and transfer of materials, loading and unloading 
operations, control of plant site run-off, worker training, building of 
containment structures or equipment, measures for containing toxic 
organic pollutants (including solvents), and/or measures and equipment 
for emergency response;
* * * * *
    (viii) Comply with the public participation requirements of 40 CFR 
part 25 in the enforcement of National Pretreatment Standards. These

[[Page 60195]]

procedures shall include provision for at least annual public 
notification in a newspaper(s) of general circulation that provides 
meaningful public notice within the jurisdiction(s) served by the POTW 
of Industrial Users which, at any time during the previous 12 months, 
were in significant noncompliance with applicable Pretreatment 
requirements. For the purposes of this provision, a Significant 
Industrial User (or any Industrial User which violates paragraphs 
(f)(2)(viii)(C), (D), or (H) of this section) is in significant 
noncompliance if its violation meets one or more of the following 
criteria:
    (A) Chronic violations of wastewater Discharge limits, defined here 
as those in which 66 percent or more of all of the measurements taken 
for the same pollutant parameter during a 6-month period exceed (by any 
magnitude) a numeric Pretreatment Standard or Requirement, including 
instantaneous limits, as defined by 40 CFR 403.3(l);
    (B) Technical Review Criteria (TRC) violations, defined here as 
those in which 33 percent or more of all of the measurements taken for 
the same pollutant parameter during a 6-month period equal or exceed 
the product of the numeric Pretreatment Standard or Requirement 
including instantaneous limits, as defined by 40 CFR 403.3(l) 
multiplied by the applicable TRC (TRC=1.4 for BOD, TSS, fats, oil, and 
grease, and 1.2 for all other pollutants except pH);
    (C) Any other violation of a Pretreatment Standard or Requirement 
as defined by 40 CFR 403.3(l) (daily maximum, long-term average, 
instantaneous limit, or narrative Standard) that the POTW determines 
has caused, alone or in combination with other Discharges, Interference 
or Pass Through (including endangering the health of POTW personnel or 
the general public);
* * * * *
    (F) Failure to provide, within 45 days after the due date, required 
reports such as baseline monitoring reports, 90-day compliance reports, 
periodic self-monitoring reports, and reports on compliance with 
compliance schedules;
* * * * *
    (H) Any other violation or group of violations, which may include a 
violation of Best Management Practices, which the POTW determines will 
adversely affect the operation or implementation of the local 
Pretreatment program.
* * * * *
    (6) The POTW shall prepare and maintain a list of its Industrial 
Users meeting the criteria in Sec.  403.3(v)(1). The list shall 
identify the criteria in Sec.  403.3(v)(1) applicable to each 
Industrial User and, where applicable, shall also indicate whether the 
POTW has made a determination pursuant to Sec.  403.3(v)(2) that such 
Industrial User should not be considered a Significant Industrial User. 
The initial list shall be submitted to the Approval Authority pursuant 
to Sec.  403.9 or as a non-substantial modification pursuant to Sec.  
403.18(d). Modifications to the list shall be submitted to the Approval 
Authority pursuant to Sec.  403.12(i)(1).

0
13. Section 403.12 is amended as follows:
0
a. By removing and reserving paragraph (a).
0
b. By revising paragraphs (b)(4)(ii) and (b)(5)(ii).
0
c. By removing paragraph (b)(5)(iii).
0
d. By redesignating paragraphs (b)(5)(iv) through (b)(5)(viii) as 
paragraphs (b)(5)(iii) through (b)(5)(vii).
0
e. By revising paragraph (b)(6).
0
f. By revising paragraph (e)(1).
0
g. By redesignating paragraphs (e)(2) and (e)(3) as paragraphs (e)(3) 
and (e)(4).
0
h. By adding a new paragraph (e)(2).
0
i. Revising newly designated paragraph (e)(3).
0
j. Revising paragraphs (g)(1), (g)(2) and (g)(3).
0
k. By redesignating paragraphs (g)(4) and (g)(5) as paragraphs (g)(5) 
and (g)(6).
0
l. By revising newly designated paragraph (g)(6).
0
m. By adding paragraph (g)(4).
0
n. By revising paragraph (h).
0
o. By revising paragraph (i)(1).
0
p. By revising paragraph (j).
0
q. By revising paragraph (k)(2).
0
r. By revising paragraphs (l) introductory text, (1)(1) introductory 
text, (l)(1)(ii), (l)(2), (m), (o)(1) introductory text, and the first 
sentence of paragraph (o)(2).
0
s. By adding paragraph (q).


Sec.  403.12  Reporting requirements for POTWs and Industrial Users.

* * * * *
    (b) * * *
    (4) * * *
    (ii) Other streams as necessary to allow use of the combined 
wastestream formula of Sec.  403.6(e). (See paragraph (b)(5)(iv) of 
this section.)
* * * * *
    (5) * * *
    (ii) In addition, the User shall submit the results of sampling and 
analysis identifying the nature and concentration (or mass, where 
required by the Standard or Control Authority) of regulated pollutants 
in the Discharge from each regulated process. Both daily maximum and 
average concentration (or mass, where required) shall be reported. The 
sample shall be representative of daily operations. In cases where the 
Standard requires compliance with a Best Management Practice or 
pollution prevention alternative, the User shall submit documentation 
as required by the Control Authority or the applicable Standards to 
determine compliance with the Standard;
* * * * *
    (6) Certification. A statement, reviewed by an authorized 
representative of the Industrial User (as defined in paragraph (l) of 
this section) and certified to by a qualified professional, indicating 
whether Pretreatment Standards are being met on a consistent basis, 
and, if not, whether additional operation and maintenance (O and M) 
and/or additional Pretreatment is required for the Industrial User to 
meet the Pretreatment Standards and Requirements; and
    (e) * * *
    (1) Any Industrial User subject to a categorical Pretreatment 
Standard (except a Non-Significant Categorical User as defined in Sec.  
403.3(v)(2)), after the compliance date of such Pretreatment Standard, 
or, in the case of a New Source, after commencement of the discharge 
into the POTW, shall submit to the Control Authority during the months 
of June and December, unless required more frequently in the 
Pretreatment Standard or by the Control Authority or the Approval 
Authority, a report indicating the nature and concentration of 
pollutants in the effluent which are limited by such categorical 
Pretreatment Standards. In addition, this report shall include a record 
of measured or estimated average and maximum daily flows for the 
reporting period for the Discharge reported in paragraph (b)(4) of this 
section except that the Control Authority may require more detailed 
reporting of flows. In cases where the Pretreatment Standard requires 
compliance with a Best Management Practice (or pollution prevention 
alternative), the User shall submit documentation required by the 
Control Authority or the Pretreatment Standard necessary to determine 
the compliance status of the User. At the discretion of the Control 
Authority and in consideration of such factors as local high or low 
flow rates, holidays, budget cycles, etc., the Control Authority may 
modify the months during which the above reports are to be submitted.
    (2) The Control Authority may authorize the Industrial User subject 
to a categorical Pretreatment Standard to forego sampling of a 
pollutant regulated by a categorical Pretreatment Standard if

[[Page 60196]]

the Industrial User has demonstrated through sampling and other 
technical factors that the pollutant is neither present nor expected to 
be present in the Discharge, or is present only at background levels 
from intake water and without any increase in the pollutant due to 
activities of the Industrial User. This authorization is subject to the 
following conditions:
    (i) The Control Authority may authorize a waiver where a pollutant 
is determined to be present solely due to sanitary wastewater 
discharged from the facility provided that the sanitary wastewater is 
not regulated by an applicable categorical Standard and otherwise 
includes no process wastewater.
    (ii) The monitoring waiver is valid only for the duration of the 
effective period of the Permit or other equivalent individual control 
mechanism, but in no case longer than 5 years. The User must submit a 
new request for the waiver before the waiver can be granted for each 
subsequent control mechanism.
    (iii) In making a demonstration that a pollutant is not present, 
the Industrial User must provide data from at least one sampling of the 
facility's process wastewater prior to any treatment present at the 
facility that is representative of all wastewater from all processes.
    The request for a monitoring waiver must be signed in accordance 
with paragraph (l) of this section and include the certification 
statement in Sec.  403.6(a)(2)(ii). Non-detectable sample results may 
only be used as a demonstration that a pollutant is not present if the 
EPA approved method from 40 CFR part 136 with the lowest minimum 
detection level for that pollutant was used in the analysis.
    (iv) Any grant of the monitoring waiver by the Control Authority 
must be included as a condition in the User's control mechanism. The 
reasons supporting the waiver and any information submitted by the User 
in its request for the waiver must be maintained by the Control 
Authority for 3 years after expiration of the waiver.
    (v) Upon approval of the monitoring waiver and revision of the 
User's control mechanism by the Control Authority, the Industrial User 
must certify on each report with the statement below, that there has 
been no increase in the pollutant in its wastestream due to activities 
of the Industrial User:

    Based on my inquiry of the person or persons directly 
responsible for managing compliance with the Pretreatment Standard 
for 40 CFR -------------- [specify applicable National Pretreatment 
Standard part(s)], I certify that, to the best of my knowledge and 
belief, there has been no increase in the level of ------------ 
[list pollutant(s)] in the wastewaters due to the activities at the 
facility since filing of the last periodic report under 40 CFR 
403.12(e)(1).

    (vi) In the event that a waived pollutant is found to be present or 
is expected to be present based on changes that occur in the User's 
operations, the User must immediately: Comply with the monitoring 
requirements of paragraph (e)(1) of this section or other more frequent 
monitoring requirements imposed by the Control Authority; and notify 
the Control Authority.
    (vii) This provision does not supersede certification processes and 
requirements established in categorical Pretreatment Standards, except 
as otherwise specified in the categorical Pretreatment Standard.
    (3) The Control Authority may reduce the requirement in paragraph 
(e)(1) of this section to a requirement to report no less frequently 
than once a year, unless required more frequently in the Pretreatment 
Standard or by the Approval Authority, where the Industrial User meets 
all of the following conditions:
    (i) The Industrial User's total categorical wastewater flow does 
not exceed any of the following:
    (A) 0.01 percent of the design dry weather hydraulic capacity of 
the POTW, or 5,000 gallons per day, whichever is smaller, as measured 
by a continuous effluent flow monitoring device unless the Industrial 
User discharges in batches;
    (B) 0.01 percent of the design dry weather organic treatment 
capacity of the POTW; and
    (C) 0.01 percent of the maximum allowable headworks loading for any 
pollutant regulated by the applicable categorical Pretreatment Standard 
for which approved local limits were developed by a POTW in accordance 
with Sec.  403.5(c) and paragraph (d) of this section;
    (ii) The Industrial User has not been in significant noncompliance, 
as defined in Sec.  403.8(f)(2)(viii), for any time in the past two 
years;
    (iii) The Industrial User does not have daily flow rates, 
production levels, or pollutant levels that vary so significantly that 
decreasing the reporting requirement for this Industrial User would 
result in data that are not representative of conditions occurring 
during the reporting period pursuant to paragraph (g)(3) of this 
section;
    (iv) The Industrial User must notify the Control Authority 
immediately of any changes at its facility causing it to no longer meet 
conditions of paragraphs (e)(3)(i) or (ii) of this section. Upon 
notification, the Industrial User must immediately begin complying with 
the minimum reporting in paragraph (e)(1) of this section; and
    (v) The Control Authority must retain documentation to support the 
Control Authority's determination that a specific Industrial User 
qualifies for reduced reporting requirements under paragraph (e)(3) of 
this section for a period of 3 years after the expiration of the term 
of the control mechanism.
* * * * *
    (g) * * *
    (1) Except in the case of Non-Significant Categorical Users, the 
reports required in paragraphs (b), (d), (e), and (h) of this section 
shall contain the results of sampling and analysis of the Discharge, 
including the flow and the nature and concentration, or production and 
mass where requested by the Control Authority, of pollutants contained 
therein which are limited by the applicable Pretreatment Standards. 
This sampling and analysis may be performed by the Control Authority in 
lieu of the Industrial User. Where the POTW performs the required 
sampling and analysis in lieu of the Industrial User, the User will not 
be required to submit the compliance certification required under 
paragraphs (b)(6) and (d) of this section. In addition, where the POTW 
itself collects all the information required for the report, including 
flow data, the Industrial User will not be required to submit the 
report.
    (2) If sampling performed by an Industrial User indicates a 
violation, the User shall notify the Control Authority within 24 hours 
of becoming aware of the violation. The User shall also repeat the 
sampling and analysis and submit the results of the repeat analysis to 
the Control Authority within 30 days after becoming aware of the 
violation. Where the Control Authority has performed the sampling and 
analysis in lieu of the Industrial User, the Control Authority must 
perform the repeat sampling and analysis unless it notifies the User of 
the violation and requires the User to perform the repeat analysis. 
Resampling is not required if:
    (i) The Control Authority performs sampling at the Industrial User 
at a frequency of at least once per month; or
    (ii) The Control Authority performs sampling at the User between 
the time when the initial sampling was conducted and the time when the 
User or the Control Authority receives the results of this sampling.
    (3) The reports required in paragraphs (b), (d), (e) and (h) of 
this section must be based upon data obtained through appropriate 
sampling and analysis

[[Page 60197]]

performed during the period covered by the report, which data are 
representative of conditions occurring during the reporting period. The 
Control Authority shall require that frequency of monitoring necessary 
to assess and assure compliance by Industrial Users with applicable 
Pretreatment Standards and Requirements. Grab samples must be used for 
pH, cyanide, total phenols, oil and grease, sulfide, and volatile 
organic compounds. For all other pollutants, 24-hour composite samples 
must be obtained through flow-proportional composite sampling 
techniques, unless time-proportional composite sampling or grab 
sampling is authorized by the Control Authority. Where time-
proportional composite sampling or grab sampling is authorized by the 
Control Authority, the samples must be representative of the Discharge 
and the decision to allow the alternative sampling must be documented 
in the Industrial User file for that facility or facilities. Using 
protocols (including appropriate preservation) specified in 40 CFR part 
136 and appropriate EPA guidance, multiple grab samples collected 
during a 24-hour period may be composited prior to the analysis as 
follows: For cyanide, total phenols, and sulfides the samples may be 
composited in the laboratory or in the field; for volatile organics and 
oil & grease the samples may be composited in the laboratory. Composite 
samples for other parameters unaffected by the compositing procedures 
as documented in approved EPA methodologies may be authorized by the 
Control Authority, as appropriate.
    (4) For sampling required in support of baseline monitoring and 90-
day compliance reports required in paragraphs (b) and (d) of this 
section, a minimum of four (4) grab samples must be used for pH, 
cyanide, total phenols, oil and grease, sulfide and volatile organic 
compounds for facilities for which historical sampling data do not 
exist; for facilities for which historical sampling data are available, 
the Control Authority may authorize a lower minimum. For the reports 
required by paragraphs (e) and (h) of this section, the Control 
Authority shall require the number of grab samples necessary to assess 
and assure compliance by Industrial Users with Applicable Pretreatment 
Standards and Requirements.
* * * * *
    (6) If an Industrial User subject to the reporting requirement in 
paragraph (e) or (h) of this section monitors any regulated pollutant 
at the appropriate sampling location more frequently than required by 
the Control Authority, using the procedures prescribed in paragraph 
(g)(5) of this section, the results of this monitoring shall be 
included in the report.
    (h) Reporting requirements for Industrial Users not subject to 
categorical Pretreatment Standards. The Control Authority must require 
appropriate reporting from those Industrial Users with Discharges that 
are not subject to categorical Pretreatment Standards. Significant Non-
categorical Industrial Users must submit to the Control Authority at 
least once every six months (on dates specified by the Control 
Authority) a description of the nature, concentration, and flow of the 
pollutants required to be reported by the Control Authority. In cases 
where a local limit requires compliance with a Best Management Practice 
or pollution prevention alternative, the User must submit documentation 
required by the Control Authority to determine the compliance status of 
the User. These reports must be based on sampling and analysis 
performed in the period covered by the report, and in accordance with 
the techniques described in part 136 and amendments thereto. This 
sampling and analysis may be performed by the Control Authority in lieu 
of the significant non-categorical Industrial User.
    (i) * * *
    (1) An updated list of the POTW's Industrial Users, including their 
names and addresses, or a list of deletions and additions keyed to a 
previously submitted list. The POTW shall provide a brief explanation 
of each deletion. This list shall identify which Industrial Users are 
subject to categorical Pretreatment Standards and specify which 
Standards are applicable to each Industrial User. The list shall 
indicate which Industrial Users are subject to local standards that are 
more stringent than the categorical Pretreatment Standards. The POTW 
shall also list the Industrial Users that are subject only to local 
Requirements. The list must also identify Industrial Users subject to 
categorical Pretreatment Standards that are subject to reduced 
reporting requirements under paragraph (e)(3), and identify which 
Industrial Users are Non-Significant Categorical Industrial Users.
* * * * *
    (j) Notification of changed Discharge. All Industrial Users shall 
promptly notify the Control Authority (and the POTW if the POTW is not 
the Control Authority) in advance of any substantial change in the 
volume or character of pollutants in their Discharge, including the 
listed or characteristic hazardous wastes for which the Industrial User 
has submitted initial notification under paragraph (p) of this section.
    (k) * * *
    (2) No increment referred to in paragraph (k)(1) of this section 
shall exceed nine months;
* * * * *
    (l) Signatory requirements for Industrial User reports. The reports 
required by paragraphs (b), (d), and (e) of this section shall include 
the certification statement as set forth in Sec.  403.6(a)(2)(ii), and 
shall be signed as follows:
    (1) By a responsible corporate officer, if the Industrial User 
submitting the reports required by paragraphs (b), (d), and (e) of this 
section is a corporation. For the purpose of this paragraph, a 
responsible corporate officer means:
* * * * *
    (ii) The manager of one or more manufacturing, production, or 
operating facilities, provided, the manager is authorized to make 
management decisions which govern the operation of the regulated 
facility including having the explicit or implicit duty of making major 
capital investment recommendations, and initiate and direct other 
comprehensive measures to assure long-term environmental compliance 
with environmental laws and regulations; can ensure that the necessary 
systems are established or actions taken to gather complete and 
accurate information for control mechanism requirements; and where 
authority to sign documents has been assigned or delegated to the 
manager in accordance with corporate procedures.
    (2) By a general partner or proprietor if the Industrial User 
submitting the reports required by paragraphs (b), (d), and (e) of this 
section is a partnership, or sole proprietorship respectively.
* * * * *
    (m) Signatory requirements for POTW reports. Reports submitted to 
the Approval Authority by the POTW in accordance with paragraph (i) of 
this section must be signed by a principal executive officer, ranking 
elected official or other duly authorized employee. The duly authorized 
employee must be an individual or position having responsibility for 
the overall operation of the facility or the Pretreatment Program. This 
authorization must be made in writing by the principal executive 
officer or ranking elected official, and submitted to the Approval 
Authority prior to or together with the report being submitted.
* * * * *

[[Page 60198]]

    (o) * * *
    (1) Any Industrial User and POTW subject to the reporting 
requirements established in this section shall maintain records of all 
information resulting from any monitoring activities required by this 
section, including documentation associated with Best Management 
Practices. Such records shall include for all samples:
* * * * *
    (2) Any Industrial User or POTW subject to the reporting 
requirements established in this section (including documentation 
associated with Best Management Practices) shall be required to retain 
for a minimum of 3 years any records of monitoring activities and 
results (whether or not such monitoring activities are required by this 
section) and shall make such records available for inspection and 
copying by the Director and the Regional Administrator (and POTW in the 
case of an Industrial User). * * *
* * * * *
    (q) Annual certification by Non-Significant Categorical Industrial 
Users. A facility determined to be a Non-Significant Categorical 
Industrial User pursuant to Sec.  403.3(v)(2) must annually submit the 
following certification statement, signed in accordance with the 
signatory requirements in paragraph (l) of this section. This 
certification must accompany any alternative report required by the 
Control Authority:

    Based on my inquiry of the person or persons directly 
responsible for managing compliance with the categorical 
Pretreatment Standards under 40 CFR --------, I certify that, to the 
best of my knowledge and belief that during the period from --------
-------- --------, to ----------------, -------- [month, days, 
year]:
    (a) The facility described as ---------------- [facility name] 
met the definition of a non-significant categorical Industrial User 
as described in Sec.  403.3(v)(2); (b) the facility complied with 
all applicable Pretreatment Standards and requirements during this 
reporting period; and (c) the facility never discharged more than 
100 gallons of total categorical wastewater on any given day during 
this reporting period. This compliance certification is based upon 
the following information:
-----------------------------------------------------------------------
-----------------------------------------------------------------------

0
14. Section 403.13 is amended by revising the first sentence of 
paragraph (g)(3) to read as follows:


Sec.  403.13  Variances from categorical pretreatment standards for 
fundamentally different factors.

* * * * *
    (g) * * *
    (3) Where the User has requested a categorical determination 
pursuant to Sec.  403.6(a), the User may elect to await the results of 
the category determination before submitting a variance request under 
this section. * * *
* * * * *

0
15. Section 403.15 is revised to read as follows:


Sec.  403.15  Net/gross calculation.

    (a) Application. Categorical Pretreatment Standards may be adjusted 
to reflect the presence of pollutants in the Industrial User's intake 
water in accordance with this section. Any Industrial User wishing to 
obtain credit for intake pollutants must make application to the 
Control Authority. Upon request of the Industrial User, the applicable 
Standard will be calculated on a ``net'' basis (i.e., adjusted to 
reflect credit for pollutants in the intake water) if the requirements 
of paragraph (b) of this section are met.
    (b) Criteria. (1) Either:
    (i) The applicable categorical Pretreatment Standards contained in 
40 CFR subchapter N specifically provide that they shall be applied on 
a net basis; or
    (ii) The Industrial User demonstrates that the control system it 
proposes or uses to meet applicable categorical Pretreatment Standards 
would, if properly installed and operated, meet the Standards in the 
absence of pollutants in the intake waters.
    (2) Credit for generic pollutants such as biochemical oxygen demand 
(BOD), total suspended solids (TSS), and oil and grease should not be 
granted unless the Industrial User demonstrates that the constituents 
of the generic measure in the User's effluent are substantially similar 
to the constituents of the generic measure in the intake water or 
unless appropriate additional limits are placed on process water 
pollutants either at the outfall or elsewhere.
    (3) Credit shall be granted only to the extent necessary to meet 
the applicable categorical Pretreatment Standard(s), up to a maximum 
value equal to the influent value. Additional monitoring may be 
necessary to determine eligibility for credits and compliance with 
Standard(s) adjusted under this section.
    (4) Credit shall be granted only if the User demonstrates that the 
intake water is drawn from the same body of water as that into which 
the POTW discharges. The Control Authority may waive this requirement 
if it finds that no environmental degradation will result.

Appendix A to Part 403 [Removed and Reserved]

0
16. Appendix A to part 403 is removed and reserved.
0
17. Appendix G to part 403 is amended as by revising Footnote 1 to 
Table I to read as follows:

Appendix G to Part 403--Pollutants Eligible for a Removal Credit

I. Regulated Pollutants in Part 503 Eligible for a Removal Credit

* * * * *
1 The following organic pollutants are eligible for a removal credit 
if the requirements for total hydrocarbons (or carbon monoxide) in 
subpart E in 40 CFR Part 503 are met when sewage sludge is fired in 
a sewage sludge incinerator: Acrylonitrile, ldrin/Dieldrin(total), 
Benzene, Benzidine, Benzo(a)pyrene, Bis(2-chloroethyl)ether, Bis(2-
ethylhexyl)phthalate, Bromodichloromethane, Bromoethane, Bromoform, 
Carbon tetrachloride, Chlordane, Chloroform, Chloromethane, DDD, 
DDE, DDT, Dibromochloromethane, Dibutyl phthalate, 1,2-
dichloroethane, 1,1-dichloroethylene, 2,4-dichlorophenol, 1,3-
dichloropropene, Diethyl phthalate, 2,4-dinitrophenol, 1,2-
diphenylhydrazine, Din-butyl phthalate, Endosulfan, Endrin, 
Ethylbenzene, Heptachlor, Heptachlor epoxide, Hexachlorobutadiene, 
Alphahexachlorocyclohexane, Beta-hexachlorocyclohexane, 
Hexachlorocyclopentadiene, Hexachloroethane, Hydrogen cyanide, 
Isophorone, Lindane, Methylene chloride, Nitrobenzene, N-
Nitrosodimethylamine, N-Nitrosodi-n-propylamine, Pentachlorophenol, 
Phenol, Polychlorinated biphenyls, 2,3,7,8-tetrachlorodibenzo-p-
dioxin, 1,1,2,2,-tetrachloroethane, Tetrachloroethylene, Toluene, 
Toxaphene, Trichloroethylene, 1,2,4-Trichlorobenzene, 1,1,1-
Trichloroethane, 1,1,2-Trichloroethane, and 2,4,6-Trichlorophenol.
* * * * *
[FR Doc. 05-20001 Filed 10-13-05; 8:45 am]
BILLING CODE 6560-50-P


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