f
4
United States
Environmental Protection
Agency
                       Office of Water
                       Office of Wastewater Enforcement and
                       Compliance (4204)
April 1994
Combined Sewer Overflows
Guidance for Permit Writers

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   -<£OSr<      UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
        *>.            WASHINGTON D.C. 20460
                                                              OFFICE OF
                                                               WATER

SUBJECT:   Combined  Sewer Over flows -Guidance  for Permit Writers
FROM:     Tony Smith/Civil Engineer/MC:4203

TO:       Interested Parties
                                               O*-N  c
     On April  11,  1994,  EPA issued  the  final  Combined Sewer
Overflow  (CSO)  Control  Policy.   The Policy establishes a
consistent national  approach for controlling  discharges from
combined  sewer systems  to  the Nation's  waters through the
National  Pollutant Discharge Elimination  System (NPDES)  permit
program.

     EPA's CSO Control  Policy encourages  municipalities,
permitting authorities,  water quality standards authorities,  and
the public to  engage in a  comprehensive and coordinated planning
effort to achieve  cost  effective CSO controls that  ultimately
complies  with  the  requirements  of the Clean Water Act (CWA).
The policy recognizes the  site  specific nature of CSO's and their
impacts and provides the necessary  flexibility to tailor controls
to local  situations.  The  Policy was, in  large part,  the product
of negotiations with key CSO stakeholders including
representatives from States,  environmental  groups,  municipal
organizations  and  others.

     EPA  is committed to aggressively implementing  the Policy by
providing the  required  tools for effective  implementation.   For
example,  EPA is currently  planning  and  developing a series  of
workshops to be held late  this  summer at  several  strategic
locations throughout the country.   These  workshops  will be
specifically designed to clarify and address  CSO  Policy and
guidance  issues.  Another  major tool to be  provided are guidance
manuals supporting the  Policy.

     The  enclosed  document,  Combined Sewer  Overflows-Guidance for
Permit Writers, is submitted for your review  and  comment. Please
note that this guidance is currently in draft form  and should not
be used as the Agency's final guidance.   It is intended as
guidance  only  and  does  not modify or supersede the  CWA or Agency
regulations.   It is  one of five draft guidance manuals that EPA
has recently released for  external  review.  These five documents
were released  simultaneously and were developed to  supplement the
1994 Combined Sewer  Overflow (CSO)  Control  Policy.


                      ITS r;v  • ••--..

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     We recognize that some reviewers may receive all five
documents and may want to comment on all of them.  Consequently,
we are asking that comments on all five be submitted no later
than July 6, 1994.  These five documents are:

     1. Combined Sewer Overflows-Guidance for Permit Writers
     2. Combined Sewer Overflows-Guidance for Screening and
        Ranking
     3. Combined Sewer Overflows-Guidance for Nine Minimum
        Control Measures
     4. Combined Sewer Overflows-Guidance for Long-Term Control
        Plan
     5. Combined Sewer Overflows-Guidance for Funding Options

     Any and all comments on this draft guidance document would
be appreciated.  Your expeditious response would greatly
facilitate the finalization of this guidance and the
implementation of the Policy.  Please send your comments on this
manual to:

          Tony Smith/MC:4203
          U.S. Environmental Protection Agency
          401 M Street, S.W.
          Washington, D.C. 20460

          Fax: (202) 260-1460

     We expect to issue these guidances in final form, based on
comments received and feedback from the workshops in September
1994.  If you have questions, you may call me on (202) 260-1017.
Please understand that I cannot take detailed comments by phone.

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                                DISCLAIMER
The policies set out in this document are not final Agency action, but are intended
solely as guidance.  They are not intended, nor can they be relied upon, to create
any rights enforceable by any party in litigation with the United States.  EPA
officials may decide to follow the guidance provided in this manual, or to act at
variance with the guidance, based on an analysis of specific site circumstances.
The Agency also reserves the right to change this guidance at any time without
public notice.

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                  ACKNOWLEDGEMENTS
                                                                               1
This guidance manual was prepared under the direction of Roberto
A. Smith, Civil Engineer, Pretreatment Branch, Permits Division,
Office  of  Wastewater  Enforcement  and Compliance,  U.S.
Environmental Protection Agency.  Assistance was provided  to
EPA by Science Applications International Corporation (SAIC),
under EPA  Contract 68-C8-0066, Work Assignment C-5-101(P).
Ms. Sara Gropen and Ms. Carol Winston were the SAIC Work
Assignment Managers. Principal authors were Mssrs. Roberto A.
Smith, Timothy Dwyer,  and Jeffrey Lape of EPA and Ms. Sara
Gropen, Ms. Carol Winston, Mr. Jim Parker, Ms. Mary Waldron,
and Mr. Mark Ernstmann of SAIC.

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                              TABLE OF CONTENTS

 CHAPTER 1.  INTRODUCTION  	1-1

       1.1   BACKGROUND  	1-1
       1.2   EVOLUTION/HISTORY OF THE CSO CONTROL POLICY  	1-1
       1.3   KEY ELEMENTS OF THE CSO CONTROL POLICY	1-3
       1.4   GUIDANCE TO SUPPORT IMPLEMENTATION OF THE CSO CONTROL
            POLICY	1-5
       1.5   PURPOSE OF MANUAL AND TARGET AUDIENCE	1-5
       1.6   ORGANIZATION OF MANUAL	1-6

 CHAPTER 2.  INTRODUCTION TO CSO PERMITTING	2-1

       2.1   INTRODUCTION	2-1
       2.2   OVERVIEW OF CSO PERMITTING APPROACH	2-1
       2.3   RESPONSIBILITY OF NPDES PERMITTING AUTHORITIES  	2-2
       2.4   CSO PERMITTING PRIORITIES AND WATERSHED CONSIDERATIONS	2-3
       2.5   CSO PERMITTING APPROACHES	2-4
       2.6   INTEGRATION OF CSO CONDITIONS INTO THE NPDES PERMIT	2-5
       2.7   COMPLEX COMBINED SEWER SYSTEMS  	2-6
       2.8   PREVIOUS OR ONGOING CSO CONTROL EFFORTS	2-7
       2.9   SMALL COMBINED SEWER SYSTEMS	2-7
       2.10  MEASURES OF SUCCESS	2-7
       2.11  COORDINATION WITH STATE WATER QUALITY STANDARDS	2-10

 CHAPTER 3.  PHASE I PERMITTING	3-1

       3.1   PHASE I PERMIT PROCESS	3-1
       3.2   INFORMATION REQUIREMENTS	3-1
       3.3   IDENTIFICATION OF CSO OUTFALLS IN THE PERMIT  	3-3
       3.4   NINE MINIMUM CONTROLS  	3-3

            3.4.1  Implementation Considerations	3-8
            3.4.2  Documentation and Reporting  	3-10

       3.5   LONG-TERM CONTROL PLAN  	3-12

            3.5.1  Components of the Long-Term Control Plan  	3-13
            3.5.2  Schedule for Development of the Long-Term Control Plan	3-27
            3.5.3  Considerations for Previous or Ongoing CSO Control Efforts
                  and Small Combined  Sewer Systems	3-29
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       3.6    EFFLUENT LIMITATIONS  	3-31

             3.6.1 Technology-Based Requirements  	3-31
             3.6.2 Water Quality-Based Requirements	3-32

       3.7    MONITORING	3-33
       3.8    REPORTING	3-35
       3.9    SPECIAL CONDITIONS	3-36

             3.9.1  CSO-Related Bypass	3-36
             3.9.2  Permit Reopener Clause	3-36

       3.10   ADDITIONAL ACTIVITIES DURING PHASE I PERMITTING  	3-37
       3.11   DEFINITIONS  	3-38

CHAPTER 4.  PHASE n PERMITTING	4-1

       4.1    PHASE n PERMIT PROCESS	4-1
       4.2    INFORMATION REQUIREMENTS	4-2
       4.3    IDENTIFICATION OF CSO OUTFALLS m THE PERMIT  	4-3
       4.4    NINE MINIMUM CONTROLS   	4-3

             4.4.1  Review of Permittee's Implementation of the Nine Minimum
                   Controls  	4-3
             4.4.2  Permit Conditions	4-9

       4.5    LONG-TERM CONTROL PLAN  	4-14

             4.5.1  Coordination of the Review and Evaluation	4-15
             4.5.2  Review of Long-Term Control Plan	4-15
             4.5.3  Implementation of the Long-Term Control Plan  	4-21

       4.6    EFFLUENT LIMITATIONS   	4-25

             4.6.1  Technology-Based Requirements	4-25
             4.6.2  Water Quality-Based Requirements	4-26

       4.7    MONITORING  	4-29
       4.8    REPORTING  	4-30
       4.9    SPECIAL CONDITIONS	4-33

             4.9.1  CSO-Related Bypass	4-33
             4.9.2  Reassessment of Sensitive Areas   	4-36
             4.9.3  Permit Reopener Clause	4-37
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       4.10  DEMOTIONS   	4-37

 CHAPTER 5. POST-PHASE n PERMITTING  	5-1

       5.1    CONTINUATION OF PHASE n	5-1
       5.2    SUBSEQUENT  CSO PERMITTING	5-1
 Appendix A.  Example CSO Permit Language  	A-l
 Appendix B.  Development and Review of Monitoring Plan	 B-l
 Appendix C.  Nine Minimum Controls Evaluation Checklist	C-l
 Appendix D.  Long-Term Control Plan Evaluation Checklist	D-l
                                 LIST OF EXHIBITS

Exhibit 1-1.  Time Sequence of Municipality and Permitting/Enforcement
             Authority Actions to Control CSOs  	1-4

Exhibit 1-2.  CSO-Related Guidance Documents	1-5

Exhibit 3-1.  Example Permit Language for Identifying CSO Outfalls
             in the Phase I Permit	3-3

Exhibit 3-2.  Examples of the Nine Minimum Controls	3-5

Exhibit 3-3.  Example Permit Language For Requiring Immediate Implementation
             of the Nine Minimum Controls	3-9

Exhibit 3-4.  Example Permit Language For Requiring Documentation and Reporting
             of the Nine Minimum Controls	3-11

Exhibit 3-5.  Example Permit Language For Requiring the Development
             of a Long-Term Control Plan	3-15

Exhibit 3-6.  Sensitive Areas Identified in the CSO Control Policy	3-20

Exhibit 3-7.  Example Permit Language For Requiring Compliance
             with Narrative Water Quality Standards	3-34

Exhibit 3-8.  Example Permit Language For a Phase I Reopener Clause	3-37
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 Exhibit 4-1.  Example Permit Language For Identifying CSO Outfalls
             in a Phase n Permit	
                                      .4-3
 Exhibit 4-2.  Example Permit Language For Continued Implementation
             of the Nine Minimum Controls	4-11

 Exhibit 4-3.  Example Permit Language For Implementing Selected CSO Controls  . . .  4-24

 Exhibit 4-4.  Example Permit Language For Performance Standards
             for the Presumption Approach   	4-28

 Exhibit 4-5.  Example Permit Language For Site-specific Monitoring Activities	4-31

 Exhibit 4-6.  Example Permit Language For Requiring Submission
             of Progress Reports	 4-32

 Exhibit 4-7.  Example Permit Language For a CSO-Related Bypass	4-35

 Exhibit 4-8.  Example Permit Language For a Sensitive Area Reassessment	4-36

 Exhibit 4-9.  Example Permit Language For a Phase n Reopener Clause	4-38
Working Draft
IV
                             April 6, 1994

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                          ABBREVIATIONS AND ACRONYMS


 BAT/BCT    best available technology economically available/best conventional pollutant
             control technology

 BMP        best management practice

 BOD        biochemical oxygen demand

 BPJ         best professional judgement

 CFR        Code of Federal Regulations

 CSO        combined sewer overflow

 CSS         combined sewer system

 CWA        Clean Water Act

 EPA        U.S. Environmental Protection Agency

 LTCP        Long-Term Control Plan

 MGD        million gallons  per day

 NMC        Nine Minimum Controls

 NPDES      National Pollutant Discharge Elimination System

 O&M        operation and maintenance

 POTW       publicly owned treatment works

 TMDL       total maximum  daily load

 TSS         total suspended solids

 WLA        wasteload allocation

 WQS        water quality standards
Working Draft
April 6, 1994

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                                     CHAPTER 1
                                   INTRODUCTION

1.1    BACKGROUND
    Combined sewer systems (CSSs) are wastewater collection systems designed to carry
sanitary sewage consisting of domestic, commercial, and industrial wastewater and surface
drainage from rainfall or snowmelt in a single pipe. During dry weather, CSSs convey
domestic, commercial, and industrial wastewater to a treatment facility. In periods of
rainfall or snowmelt, total wastewater flows can exceed the capacity of the CSS and/or
treatment facilities.  When this occurs, the CSS overflows directly to surface water bodies,
such as lakes, rivers, estuaries,  or coastal waters.  These overflows—called combined sewer
overflows (CSOs)—are a major source of water pollution in communities served by CSSs.
CSSs serve about 43 million people in approximately 1,100 communities nationwide.  Most
of these communities are located in the Northeast and  Great Lakes regions.

    Because CSOs comprise untreated domestic, commercial, industrial wastes and wet
weather flows, many different types of contaminants are present.  Contaminants include
pathogens, oxygen-demanding pollutants, suspended solids, nutrients, toxics, and floatable
matter.  Because of these contaminants, CSO discharges can cause a variety of adverse
impacts on the physical characteristics  of surface waters and the viability of aquatic habitats.
CSOs have been shown to be a  major contributor to use impairment in many receiving
waters and have contributed to shellfish harvesting restrictions, beach closures, and even
occasional fish kills.

1.2    EVOLUTION/HISTORY OF THE CSO CONTROL POLICY
    Historically, the control of CSOs has proven to be extremely complex.  This complexity
stems partly from the difficulty  in quantitatively determining CSO impacts on receiving water
quality and  the site-specific variability in the volume, frequency, and characteristics of CSO
discharges.  In addition, the financial considerations for communities with CSOs can be
significant.  The U.S. Environmental Protection Agency's (EPA) 1992 NEEDS survey
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 estimates the CSO abatement costs for the 1,100 communities served by CSSs to be
 approximately $41.2 billion.

    To address these challenges, EPA's Office of Water issued a National Combined Sewer
 Overflow Control Strategy on August 10, 1989.  The Strategy reaffirmed that CSOs are point
 source discharges subject to National Pollutant Discharge Elimination System (NPDES)
 permit requirements and to the Clean Water Act (CWA).  The Strategy recommended that all
 CSOs be identified and categorized according to their status of compliance with these
 requirements.  The Strategy set forth three objectives:

    •  Ensure that if CSOs occur, they are only as a result of wet weather
    •  Bring all wet weather CSO discharge points into compliance with  the technology-
       based and water quality-based requirements of the CWA
    •  Minimize the impacts on water  quality, aquatic biota, and human  health from CSOs.

In addition, the Strategy charged all  States with producing, by January 16, 1990, state-wide
permitting strategies designed to reduce pollutant discharges from CSOs.

    Although the Strategy was successful in focusing increased attention on CSOs, it fell
short in resolving  many fundamental issues.  In mid-1991, EPA initiated  a process to
accelerate implementation of the Strategy that included negotiations with  representatives for
the regulated communities, State regulatory agencies, and environmental groups.  These
negotiations  were  conducted through the Office of Water's Management Advisory Group.
The initiative resulted in the development of a CSO Control Policy, which was published in
the Federal Register on [insert date] The intent of the Policy is to:
   •   Provide guidance to permittees with CSOs, NPDES permitting and enforcement
       authorities, and State water quality standards (WQS) authorities
   •   Ensure coordination among the appropriate parties in planning, selecting, designing,
       and implementing CSO management practices and controls to meet the requirements
       of the CWA
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  1         •  Ensure public involvement during the decision-making process.
  2

  3         The Policy contains provisions for developing appropriate, site-specific NPDES permit
  4      requirements for all CSSs that overflow due to wet weather events. The Policy also

  5      announces an enforcement initiative that requires the immediate elimination of overflows that
  6      occur during dry weather and ensures that the remaining CWA requirements are complied

  7      with as soon as possible.

  8

  9      1.3   KEY ELEMENTS  OF THE CSO CONTROL POLICY

 10         The Policy delineates clear expectations for permittees, NPDES permitting and

 11      enforcement authorities, and State WQS authorities. Key elements of the Policy include:
 12

 13         •  Permittees should immediately implement the Nine Minimum Controls (NMC), which
 14            are technology-based actions or measures that can reduce CSOs and their effects on
 15            receiving water quality (no later than January 1, 1997).
 16
 1.7         •  Permittees should give priority attention to environmentally sensitive areas.
 18
 19         •  Permittees should develop Long-Term Control Plans (LTCPs) for controlling CSOs.
20            CSO plans address one of two approaches:  1) CSO controls that are demonstrated to
21            contribute to the achievement of WQS, or 2) CSO controls that include minimum
22            treatment (e.g., primary clarification of at least 85 percent of the collected combined
23            sewage flows) that are presumed to meet WQS.
24
25         »  States should review and revise, as appropriate, State WQS during the CSO long-term
26            planning process.
27
28         •  NPDES authorities should consider the financial capability of permittees  when
29            developing CSO control plans.
30

31         The Policy also addresses important issues such as ongoing or completed projects, public

32     participation, small communities, and watershed planning.

33
34         Exhibit 1-1 illustrates the CSO responsibilities of a permittee and permitting/enforcement

35     authority, how they interact to implement the Policy, and the approximate timeframe required
36     for implementing an LTCP for CSOs.


       Working Draft                           1-3                             April 6, 1994

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                              April 6, 1994

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1.4   GUIDANCE TO SUPPORT IMPLEMENTATION or THE CSO CONTROL POLICY
   To help CSO permittees and NPDES permitting and WQS authorities successfully
implement the provisions of the CSO Control Policy, several guidance documents have been
developed to support the Policy.  Exhibit 1-2 identifies each guidance document and its
purpose.
EXHIBIT 1-2. CSO-RELATED GUIDANCE DOCUMENTS
Title
Combined Sewer Overflows— Guidance for Permit
Writers
Combined Sewer Overflows— Guidance for Screening
and Ranking
Combined Sewer Overflows— Guidance for Nine
Minimum Control Measures
Combined Sewer Overflows— Guidance for
Monitoring and Modeling
Combined Sewer Overflows — Guidance for Long-
Term Control Plan
Combined Sewer Overflows — Guidance for Financial
Capability Assessment
Combined Sewer Overflows— Guidance for Funding
Options
Purpose
Provides guidance on writing NPDES permits for
CSO controls
Provides criteria for establishing priorities for CSO
control
Provides guidance on implementing the nine
minimum controls
Provides guidance on monitoring, modeling, and
system characterization
Provides guidance on developing a long-term CSO
control plan
Provides guidance on assessing the affordability of
CSO controls
Provides options for funding CSO controls
1.5   PURPOSE OF MANUAL AND TARGET AUDIENCE
   This manual provides guidance to NPDES permitting authorities and permit writers to
develop and issue NPDES permits to control CSOs in accordance with the expectations of the
CSO Control Policy. It translates the CSO Control Policy into instructions, procedures, and
example permit language that permit writers can use to develop defensible and enforceable
NPDES permit requirements. Emphasis is placed on the role of the permit writer as the
facilitator and coordinator of the CSO control program to achieve compliance with the CWA,
including attainment of WQS.  This guidance assumes the permit writer is responsible for
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 ensuring coordination and involvement with WQS authorities, enforcement authorities, the
 public, and the permittee.

    This manual is designed to be used by EPA and State NPDES permit writers who possess
 a working knowledge of the CWA and NPDES permit regulations and requirements to
 control point source discharges.  Therefore, it provides guidance for developing CSO-related
 permit conditions; it does not provide information available in other NPDES permit guidance
 manuals, such as the training manual for NPDES permit writers. In addition, this manual
 does not provide technical guidance on the operation of CSSs and the control of CSOs.
 Information on these topics is contained in other CSO guidance manuals.  It is recommended
 that the permit writer obtain all of the CSO guidance manuals and use them  in conjunction
 with this manual during the development and issuance of permits.

 1.6    ORGANIZATION OF MANUAL
    Chapter 2 presents an overview of the approach to CSO permitting as envisioned by the
 CSO Control Policy. The chapter explains the responsibilities of NPDES permitting
 authorities, the setting of permitting priorities, and the various strategies available to EPA
 Regions and States for ensuring that the CSO Control Policy objectives are met.  Chapter 3
 presents guidance on and example permit language for developing initial (Phase I) permit
 requirements for establishing minimum technology-based control measures and initiating the
 development of long-term plans for CSO controls. Chapter 4 provides the procedures,
 requirements, and example permit language for the second round (Phase n) of CSO permits,
 which implement the selected long-term CSO control measures.  The manual concludes with
 Chapter 5, which discusses the development of post-Phase n permit requirements, including
completion of the construction and implementation of the long-term CSO control  measures,
as well as post-construction monitoring.
       Working Draft
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                                     CHAPTER 2
                         INTRODUCTION TO CSO PERMITTING

2.1    INTRODUCTION
   The CSO Control Policy provides a national strategy for the control of CSOs. This Policy
presents a uniform, nationally consistent permitting approach that will, for the first time, result
in the establishment of both technology-based and water quality-based requirements for all CSOs.
Although the permitting approach envisioned for CSOs is similar to the permitting approach that
most NPDES permit writers are  familiar with and have routinely employed for other point
source discharges, it is unlike the conventional NPDES permitting approach in many ways. This
chapter, as well as the rest of the guidance manual, is designed to provide the permit writer with
a clear understanding of the approach for CSOs, as envisioned by the CSO Control Policy.  In
addition, this guidance manual will provide the permit writer with an understanding of how to
integrate CSO controls into the NPDES permitting process.

2.2    OVERVIEW OF CSO PERMnnNG APPROACH
   The CSO Control Policy envisions that CSO  control requirements will be implemented
through NPDES permits.  The CWA requires that NPDES permits include both technology-
based and water quality-based effluent limitations.  In the absence of national effluent guidelines
for CSOs, the CSO Control Policy envisions that technology-based controls will be established
on a case-by-case basis using the permit writer's best professional judgement (BPJ) and be
expressed in the form of best management practices (BMPs).  These NMC, in most cases, will
satisfy  the technology-based requirements of the  CWA.  In addition, the CSO Control Policy
envisions that water quality-based effluent limits will be expressed in the form of narrative
requirements, performance-based standards  for  the CSS  system,  and,  ultimately,  where
appropriate,  as numeric effluent limits.

   The CSO Control Policy expects that CSO controls  through NPDES permits will occur in
a two-phased process.  During the first permit phase or the Phase I permit, the permittee will
be required to implement and demonstrate the implementation of the NMC (technology-based
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  1     effluent limits on a BPJ basis) and to initiate development of an LTCP.  It is expected that
  2     immediate implementation of the NMC will achieve an interim level of CSO control during the
  3     time  period that  the permittee is developing an  LTCP.   Once the permittee and NPDES
  4     permitting authority have selected the CSO controls as part of the LTCP, the Phase n permit
  5     will  require their  implementation.   The  Phase n permit will  also  require  continued
  6     implementation of the NMC as part of the LTCP.  These actions will result in  additional site-
  7     specific technology-based controls, as well as water quality-based performance standards.  The
  8     second phase of CSO permitting may continue for several permit cycles until all of the selected
  9     CSO  controls identified in the LTCP have been constructed and implemented.
10
11        Although the two-phased approach may be appropriate if a permittee has not implemented
12     any CSO controls, in many instances, the separation between permit phases may  not be distinct.
13     In these cases, permits may contain both Phase I and  Phase n elements.  For example, a
14     permittee may have already evaluated and selected CSO controls for a portion of its CSS but not
15     evaluated and implemented the appropriate NMC.  Thus, the first permit subsequent to the CSO
16     Control Policy issuance may include the Phase  I requirement  to evaluate, implement, and
17     document the implementation of the NMC and may  also include a Phase n requirement to
18     implement the selected CSO  controls.  The CSO Control Policy is designed to accommodate
19     these variations in the development and implementation of CSO control programs consistent with
20     the Policy.
21
22     2.3    RESPONSIBILITY OF NPDES PERMITTING AUTHORITIES
23        The permit writer's role in the CSO permitting process is extremely critical and is expected
24     to differ greatly from the NPDES permit writer's traditional role.  The permit writer's role in
25      the CSO permitting process is particularly important because he/she is responsible for facilitating
26     the development of CSO permit requirements and the opportunity to develop a broad base of
27     support for the CSO planning process and proposed CSO controls.  Not only will the permit
28      writer be involved  in a  permit priority setting  process, the permit writer is expected  to
29      coordinate with State and local agencies and  interested citizens for all CSO-related permitting
30      issues. The permit writer's coordination role may be comparable to a team leader. The permit
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writer will serve as the focal point for coordination with other State authorities, including the
WQS authority, the permittee, environmental groups, and other interested or CSO-affected
public and is expected to coordinate many different aspects of the permitting process.   In
addition, because compliance  schedules must be incorporated into an enforceable mechanism
when a  permittee  cannot  immediately comply with technology- or water  quality-based
requirements, the permit writer must also coordinate with enforcement staff.

    The permit writer's role is also expected to differ from the traditional NPDES permitting role
in that it will be ongoing and continuous.   Even after the issuance of the Phase I permit, the
permit writer will be continuously reviewing interim LTCP deliverables and other submissions,
participating in  the ongoing consensus building process, and developing and preparing for the
issuance of subsequent Phase n permits.

    Significant opportunities may  also exist for the  permit writer to assist  communities in
coordinating aspects of their CSO control programs.  In particular, this may be the case for
adjacent small communities  discharging to the same receiving water.  These communities may
save  significant resources  by coordinating the characterization of the sewer system and
monitoring the  impacts on  the receiving water  quality rather than pursuing these activities
separately. The permit writer may encourage community coordination through several means.
For example, the permit writer can advise adjacent communities of their mutual interests and
opportunities for coordination.  This coordination opportunity may also be considered during the
permitting prioritization process.

2.4    CSO PERMrrnNG PRIORITIES  AND WATERSHED CONSIDERATIONS
    In response to the 1989 CSO Strategy, 30 States developed CSO permitting strategies. These
strategies usually provided a priority setting  plan for CSOs.  EPA expects States to evaluate the
need to revise their CSO strategies for consistency with  the new CSO Control Policy.  This
represents an opportunity for permitting authorities to reconsider their CSO permitting priorities
in light of current or suspected environmental impacts, watershed permitting initiatives, and
other factors. States and EPA should review these strategies and establish appropriate permitting
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  1     priorities  for implementation  of the CSO Control Policy.  In establishing CSO permitting
  2     priorities, the NPDES permitting authority should consider the environmental impacts of CSOs,
  3     such as beach closings, human health hazards, and the presence of endangered species.  The
  4     NPDES permitting authority should also consider requiring immediate action for CSOs that
  5     discharge  to "sensitive areas."  The Combined Sewer Overflows—Guidance for Screening and
  6     Ranking (EPA, 1994) can be used as a tool for establishing priorities consistent with the CSO
  7     Control Policy.
  8
  9        To the greatest extent possible,  NPDES permitting authorities are encouraged to evaluate
10     water pollution control needs  on a watershed management basis and coordinate CSO control
11     efforts with other point and nonpoint source control activities.  In certain cases, the permit writer
12     may want to approach CSO permitting on the basis of the overall protection of a watershed.
13     This would be particularly true in situations where non-CSO point  source discharges and
14     nonpoint source discharges contribute to the adverse impacts on the receiving water quality.
15     EPA encourages the use  of the watershed approach  to concurrently control both point and
16     nonpoint sources of pollution within the same geographic area to contribute to the achievement
17     of WQS.  A comprehensive watershed approach also allows the NPDES permitting authority to
18     make better use of limited resources in achieving WQS.
19
20     2.5    CSO PERMITTING APPROACHES
21         The CSO Control Policy envisions that, in most cases, CSO requirements and controls will
22     be incorporated into a municipality's existing NPDES permit for its discharge from the publicly
23     owned treatment works (POTW), much like the incorporation of pretreatment and  sludge
24     requirements.  CSO conditions may be incorporated into the NPDES permit in several ways:
25     1) by including the conditions in the permit during the next 5-year permit renewal cycle (permit
26     reissuance),  2) by modifying the permit for cause in accordance with the criteria in 40 CFR
27     Section 122.62(a) (incorporation   of CSO  conditions  would represent  a  major  permit
28     modification),  or 3) by revoking and reissuing  the permit  for cause in accordance with the
29      criteria in 40 CFR Section 122.62(b) (permit revocation).  Because it is unlikely the permit
30     writer  will immediately incorporate  CSO conditions into applicable NPDES permits,  the
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  1     permitting authority is encouraged to inform affected parties of the impending changes and
  2     encourage them to take steps to voluntarily implement the CSO Control Policy requirements,
  3     especially the NMC.  For illustrative purposes, this guidance  document assumes that CSO
  4     conditions will be incorporated into NPDES permits during the next 5-year permit renewal cycle
  5     (permit reissuance).  It is anticipated that most permit writers will choose permit reissuance as
  6     the means to incorporate CSO conditions into NPDES permits.
  7
  8     2.6    INTEGRATION OF CSO CONDITIONS  INTO THE NPDES PERMIT
  9         It is recommended that the permit writer integrate CSO conditions into an existing NPDES
 10     permit in one of two ways.  The CSO conditions can be grouped together and contained in a
 11     separate section of the NPDES permit the same way that sludge or pretreatment requirements
 12     are often  placed  in a separate section.  Alternatively, individual  CSO  conditions  can  be
 13     integrated into separate subsections of the NPDES permit. For example, CSO conditions can
 14     be integrated into the effluent limitations, monitoring requirements, and special conditions
 15     sections of the permit, as appropriate. Numerous examples of permit language for CSO-related
 16     requirements  are  given throughout this manual.   These examples have been compiled in
 17     Appendix A to illustrate how the CSO conditions can be grouped together in a separate section
 18     of an NPDES permit.
 19
 20        This guidance  document assumes that the CSO conditions will  be grouped together in a
 21     separate section of the permit (see Appendix A). If the NPDES permit is not the appropriate
 22     mechanism to initiate or require CSO control, other tools are available to the NPDES permitting
 23     authority.  For example, the permitting authority may request information under Section 308 of
 24     the CWA (or State equivalent) that includes information on a community's CSS. Much of the
 25     example NPDES permit language can be used in a Section 308 information request.  In addition,
26     the use of enforceable orders in conjunction with NPDES permits may be necessary  when a
27     permittee cannot immediately comply with the terms of the NPDES permit and compliance dates
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2.7    COMPLEX COMBINED SEWER SYSTEMS
   A single system-wide permit should be issued for all CSO outfalls from a single authority.
For example, a municipality or a small sanitary authority with one POTW treatment plant should
be issued one NPDES permit that addresses requirements for the POTW, as well as for CSOs,
stormwater, sludge, and pretreatment control programs, as appropriate. This is the simplest and
most common situation that the permit writer will encounter.

   If a large municipality or authority has two or more POTW treatment plants served by CSSs
and each has its own NPDES permit, the  NPDES permits should require a comprehensive,
system-wide approach  to CSO control.  This is similar to requirements for a  system-wide
pretreatment program,  where one municipality owns several POTWs.  To incorporate CSO
conditions into each permit, the permits should be renewed, revoked, and reissued or modified
to include CSO conditions. For example, if a city  has three POTWs with individual permits that
will be renewed in different years (e.g., POTW A's permit will be renewed in 1994, POTW B's
permit will be renewed in 1995, and POTW C's permit will be renewed in 1996), conditions
addressing all CSOs can  be incorporated into each permit upon renewal.  To begin the LTCP
development process without having to wait for all of the permits to be reissued, POTW A's
permit should address  CSOs within the entire jurisdictional boundaries, including the areas
discharging to POTWs B and C, and should require development of an LTCP for the entire
system.

   In some cases, different parts of a CSS, as well as the POTW, may be owned or operated
by more than one authority.  In this case, the permit  writer may issue each authority its own
permit, including CSO conditions.   The permits  will  require coordinated preparation and
implementation of CSO controls. The individual authorities should be responsible for their own
discharges and should cooperate with the POTW  permittee receiving the flows from the CSS.
If a CSS is permitted separately from the POTW, both permits should be cross-referenced for
informational purposes.   Alternatively, the permit writer can issue a single permit to all users,
incorporating CSO conditions unique to each CSS.
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  1      2.8    PREVIOUS OR ONGOING CSO CONTROL EFFORTS
  2         Some permittees may have already completed portions of the CSO control planning and
  3      implementation process.  The CSO Control Policy recognizes these ongoing CSO control efforts
  4      and  does not expect duplication of effort. If the permittee has 1) completed or substantially
  5      completed construction of CSO control facilities that have been determined to contribute to the
  6      achievement of WQS, 2) already substantially developed or is implementing a CSO control
  7      program pursuant to an existing permit or enforcement order that is expected to be adequate to
  8      contribute to the achievement of WQS, or 3) has previously constructed CSO control facilities
  9      but has failed to comply with WQS, the permit writer should take these efforts into account in
 10      determining which of the LTCP elements are still appropriate and consistent with the goals of
 11      the CSO Control Policy.  Section 3.5.3 presents additional discussion of ongoing efforts.
 12
 13      2.9    SMALL COMBINED SEWER SYSTEMS
 14        The CSO Control Policy recognizes that the development and implementation of an LTCP
 IS      may be difficult or inappropriate for some small municipalities.  At the discretion of the permit
 16      writer, jurisdictions with total populations under 75,000 may not need to complete all of the
 17      formal steps involved in developing an LTCP. However, certain  requirements of the  CSO
 18      Control Policy may not be waived,  such as implementation of the NMC,  public participation
 19      during the  LTCP, and sensitive area considerations.  Although the CSO Control Policy is
20      intended to provide some relief for  small municipalities, the permit writer should discuss the
21      scope of the LTCP with the permittee and the WQS authority to ensure that the LTCP includes
22      sufficient information to select appropriate CSO controls. Section 3.5.3 discusses considerations
23      for small systems in greater detail.
24
25      2.10   MEASURES OF SUCCESS
26        As communities, NPDES  authorities, and  the public embark on a coordinated effort to
27      address CSOs, serious considerations should be given to "measures of success."  For purposes
28      of this discussion,  "measures of success"  are objective, measurable and quantifiable data and
29      information that over time is able to show trends and results. For example, an individual about
30      to commit to a routine of exercise might desire information on his health (e.g., weight, heart
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 rate, blood pressure, cholesterol levels) and endurance (miles jogged and elapsed time). Over
 time, the individual can show trends and specifically quantify the benefits and results of the
 investment.

    Measures of success for environmental programs generally fall into four broad categories:
 programmatic measures; environmental indicators;  environmental  measures;  and ancillary
 measures. Programmatic measures tend to measure programmatic and administrative activities
 or expenditure.  Environmental indicators are measures that suggest trends or improvements
 (e.g., pollutant  loadings reduced) but may fall short  in  demonstrating  achievement  of
 environmental objectives. Environmental measures are direct measures of public health and the
 environment. These measures are usually the best indicators of ultimate environmental success.
 However, the collection of data and information (environmental measures)  to demonstrate
progress are often the  most expensive and difficult to  obtain.  Ancillary measures refer to
 secondary benefits, results which are not directly intended, but nevertheless are of quantifiable
value or benefit to society. EPA's experience has shown that measures of success should include
a balanced  mix  of programmatic measures,  environmental indicators  and environmental
 measures.

   As communities begin to collect data and information on CSOs and CSO impacts, they have
an important opportunity to establish a solid understanding of the "baseline" conditions and
consider what information and data is necessary to evaluate and demonstrate the results of CSO
control.  Communities and NPDES authorities should agree early in the planning stages on the
data and information that will comprise the measures of success.

   Following are examples of potential measures of success for CSO control, organized by the
four categories discussed above:
   •  Programmatic or implementation measures—Information that demonstrates progress
      on implementation of CSO Controls.  For example:
      -  Number of NPDES permits issued requiring the nine minimum controls
      -  Number of NPDES permits issued requiring development of LTCPs
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       -  Number of communities meeting technology-based requirements
       -  Number of communities meeting long-term control requirements and meeting water
          quality-based requirements
       -  Compliance rates with CSO requirements
       -  Dollars spent/committed for CSO control measures
       -  Nature and extent of CSO controls constructed/implemented

    •  Environmental indicators—Information that suggests that environmental improvements
       may be attained.  These usually portray long-term trends. For example:

       -  Number of dry weather overflows eliminated
       -  Number of CSO discharge points eliminated
       -  Reduction in frequency of overflow events
       -  Volume of CSO untreated/treated discharges reduced
       -  Pollutant loadings (conventional and toxics) reduced/eliminated

    •  Environmental measures—Information that clearly demonstrates human and ecosystem
       health.  Examples may include:         *.

       -  Beach closures/shellfish closures/fish kills eliminated or reduced
       -  Protected drinking water supplies
       -  Biodiversity indices
       -  Waters meeting designated uses

    •  Ancillary benefits—Information that shows the nature and extent of secondary benefits
       which are also achieved from  the control of CSOs, such as:

       -  Improved access to water resources (e.g., environmental equity)
       -  Reduced flooding and drainage problems
       -  Reduced costs and treatment of drinking water
       -  Monetized benefits  (e.g.,  value of increased tourism, value of shellfish  harvested
          from beds previously closed, etc.)
       -  Improved quality of life (nonmonetary) as evidenced by restored habitat.


   When establishing CSO measures of success, communities and NPDES should consider a
number of important factors:
   •  Data quality and reproducibility—Can consistent and comparable data be collected that
      allows for comparison over time (e.g., trend analysis) and from different sources (e.g.,
      watershed analysis)?  Do standard data collection procedures exist?

   *  Costs—What is the cost of collecting and analyzing the information?
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       Comprehensibility to the public—Will the public understand and be able to relate to the
       measures?
       Availability—Is it reasonably feasible for the data to be collected?
       Objectivity—Would different individuals evaluate the data or information in the same
       way, free from bias or subjectivity?
    Careful selection, collection, analysis and presentation of data and information related to
measures  of success will ensure that communities, States and EPA will have the ability to
demonstrate the benefits and long-term successes of CSO control efforts.  EPA is beginning an
effort to evaluate and develop national measures of success for CSOs which will facilitate EPA's
ability to provide meaningful guidance to communities and States. Notwithstanding this effort,
communities should identify appropriate measures, document the baseline conditions, and collect
appropriate information that demonstrates the cause and effect of CSO impacts and the benefits
and success of CSO control. It is important to note that environmental measures will most likely
vary from community to community and will be determined by the site specific environmental
impacts of their respective CSOs.

2.11   COORDINATION WITH STATE WATER QUALITY STANDARDS
    A primary objective of the LTCP  is to develop and evaluate a range of CSO  control
options/strategies that will be sufficient to meet WQS by protecting designated uses of CSO
impacted receiving waters.  To ensure that the LTCP  will meet this  objective, the WQS
authorities, in conjunction with NPDES permitting authorities and the permittee, should be
involved early in the plant preparation process.  This will allow for everyone involved to have
an opportunity to assess the attainability of designated uses, and possibly determine other more
precise designated  use  classifications for the CSO impacted waters.  Therefore, the WQS
authorities should also be involved in the decision process regarding the nature and extent of data
and information to be collected for developing the LTCP. This information can also be used
to review and possibly revise the current WQS (designated uses and criteria) to reflect the site-
specific wet weather impacts for CSO impacted receiving waters. The Policy recognizes that
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the review and appropriate revision of WQS is an integral part for the development of the
LTCP.

    Data needs, monitoring protocols and models to be used for system characterization and
compliance monitoring should also be agreed on early in the process. The water quality impacts
of the existing CSOs can then be evaluated to establish a baseline against which the effectiveness
of the selected CSO controls can be measured. These models and protocols can also be used
to determine if WQS will be met after the LTCP has been implemented. If they are not met,
this information can then  be used to identify additional CSO control measures required to
achieve WQS.  This can include another review of WQS for possible revision.

    Opportunities exist  for both the municipalities and States to share and  coordinate this
information with other municipalities within the same watershed. This information, along with
stormwater and other point and non-point source data, will provide an opportunity for NPDES
authorities and permittees to implement a comprehensive watershed management approach. This
same information also provides an opportunity for municipalities to coordinate the development
and implementation of their individual LTCP with one another.
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                                     CHAPTER 3
                                PHASE I PERMITTING

    This chapter provides the permit writer with guidance related to developing and issuing initial
or Phase I NPDES permits for CSOs.  This guidance includes developing permit conditions for
implementation of the NMC and development of the LTCP to meet the technology- and water
quality-based requirements of the CWA.

3.1    PHASE I PERMIT PROCESS
    Consistent with the CSO Control Policy, the NPDES permitting authority and the individual
permit writer should approach the CSO permitting process as a two-phased process (i.e., Phase
I and Phase n). The Phase I permit should require the permittee to immediately implement the
NMC, document implementation of the NMC, and initiate and complete development of the
LTCP.  The permit should also require the permittee to gather data to establish the baseline
conditions against which CSO control actions will be measured.

3.2    INFORMATION REQUIREMENTS
   In general, the permit writer may draft and issue a Phase I permit with a minimal amount
of CSO information.  The data needed for developing the Phase I permit are not extensive
because the permit writer can require the implementation and documentation of the NMC and
development of the LTCP in a generic manner without site-specific data.   Much of the data
collection will occur during implementation of the NMC and development of the LTCP. Thus,
although the CSO information base  may not be extensive at the outset of the Phase I permitting
process, the information base will grow and evolve during  the term of the Phase I permit.

   The permit writer may use only a minimal amount of basic information to draft and issue
a Phase  I  permit;  however,  the  permit writer must  have a clear understanding  of  the
jurisdictional  boundaries and responsibility for the CSS.  This information is necessary to
determine to which NPDES permittee the CSO-related permit  conditions apply.  In many cases
where the CSS and POTW are operated by a single authority, the permit will  be issued to a
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 single municipality.  Frequently, however, the relationship may be more complicated; several
 municipalities may own part of the CSS but discharge to a single POTW treatment plant.  In this
 case, the CSO-related permit conditions may be imposed on several different permittees.

    In addition, the permit writer must have a thorough understanding of the permittee's past and
 current progress toward controlling CSOs. First, the permit writer must know which, if any,
 of the NMC have already been implemented because,  in  this case, the permit writer may
 determine that site-specific rather than generic  permit language is more appropriate.  (See
 Section 4.4.2 for a discussion of NMC site-specific permit language.) The permit writer must
 also know if the permittee has substantially developed a CSO control plan or is implementing
 a CSO control program, or if the permittee has substantially completed construction of CSO
 control measures.  Moreover, the permit writer should be aware that some municipalities may
 be  developing and implementing stormwater controls for  separate  municipal  storm sewer
 systems.  If the permittee has completed efforts to control CSOs, the permit writer should take
 this progress into account in drafting the Phase I permit.  The permit writer should also know
 the approximate population of the community served by the CSS.   If the CSS is a  "small
 system,"  the permit writer has the discretion to give special consideration to the permittee in
 developing the LTCP. (See Section 3.5.3 for further discussion regarding ongoing CSO control
 efforts and small system considerations.)

   In some instances, pertinent CSO information may be difficult to obtain.  In any event, the
permit writer should develop permit conditions requiring the permittee to implement the NMC,
 document implementation,  and develop the LTCP as soon as practical using  readily available
 information.

   Information may be available in the NPDES permit application or it may be obtained through
 informal request by letter, telephone, or in-person visits.  The permit writer may also use a more
 formal mechanism, such as a CWA Section  308 information request  or  State Section 308
equivalent. The Section 308 information request is likely to be the most effective approach to
obtain information efficiently because failure to comply with this  request can result in an
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enforcement action. The permit writer should follow the EPA Regional or State-specific policies
regarding such information requests.

3.3    IDENTIFICATION  OF CSO OUTFALLS IN THE  PERMIT
    The permittee may not have identified the locations of all CSO outfalls prior to the issuance
of the Phase I permit, although this is a desirable goal.  To the extent that the CSO outfalls are
known, the permit writer should list them in the permit.  However, if the exact location and
number of all outfalls are not known, the permit writer does not need to wait to issue the Phase
I permit until this information is  available but should include generic  permit language to
encompass all CSOs. All CSO outfalls should be identified as the municipality characterizes its
system during LTCP development.  Exhibit 3-1 provides example permit  language for a CSS
for which all CSO outfalls are  not known prior to issuance of the Phase I  permit.
     EXHIBIT 3-1.  EXAMPLE PERMIT LANGUAGE FOR IDENTIFYING CSO OUTFALLS
                               IN THE PHASE I PERMIT
 The permittee is authorized to discharge from the CSO outfalls listed below and additional CSO
 outfalls within the boundaries of the jurisdiction identified after the effective date of the permit.
 The permittee shall ensure that all CSOs from the CSS comply with the requirements of [insert
 appropriate permit section containing CSO requirements] and other pertinent portions of this
 permit.
     Overflow Number Overflow Outfall Location    Receiving Water Body
     [insert number]   [insert latitude/longitude
                     (street address optional)]
[insert receiving water body]
3.4    NINE MINIMUM CONTROLS
   The Phase I permit should require all permittees to immediately implement technology-based
requirements  (best available technology  economically achievable/best conventional pollutant
control technology [BAT/BCT]),  which, in  most  cases, are expected to be the NMC, as
determined on a BPJ basis by the NPDES permitting authority. NMC are control measures that
can reduce CSOs and their effect on receiving water quality.  They do not require significant
engineering studies or major  construction  and can be implemented in  a relatively short
timeframe. The CWA requires compliance with technology-based requirements as of March 31,
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 1989.   Thus,  if immediate compliance with the NMC cannot be achieved,  an enforceable

 mechanism should accompany the permit. As stated in the CSO Control Policy, the enforcement

 mechanism should  require compliance with NMC requirements as soon as practicable, but no

 later than January 1, 1997. (See Section 3.4.1 for more detail.) The Phase I permit should also

 require the permittee to document the implementation of the NMC as soon as  possible, but

 within 2 years of issuance or modification of the permit.


   The intent  of the NMC is to provide technology-based controls, applied on a site-specific

basis, that will immediately reduce CSO impacts on water quality and that can be implemented

early  in the control process without in-depth studies, such as those required for the LTCP.

Exhibit 3-2 briefly  describes examples of each control measure.  For further discussion on the

use of the NMC to satisfy the  BAT/BCT requirement on a BPJ basis, see Section 3.6.  The

Combined Sewer Overflows—Guidance for Nine Minimum Control Measures (EPA, 1994) serves

as a companion technical document to this manual and provides  a detailed description of the

NMC, example control measures for each of them, and the advantages and limitations associated

with various control measures.


   Implementation of the NMC involves the following distinct steps:


   •   Evaluating alternative control measures for implementing each  of  the  NMC.  The
       permittee should be required to evaluate and select alternative control measures to meet
       the NMC.

   •   Implementing the most appropriate control measures. The permittee should be required
       to implement the control  measures based on site-specific considerations. Immediate
       implementation will enable the permittee to achieve an intermediate level of CSO control
       while the LTCP  is being developed.  The control measures implemented during the
       period of the Phase I permit will be re-evaluated and refined as appropriate during the
       development of LTCP.

   •   Documenting implementation of the selected control  measures.  This  documentation of
       the selected  control measures must be adequate to confirm their implementation.  This
       documentation will also be used to help establish  the  existing baseline conditions,
       evaluate the efficacy of CSO controls, and determine the baseline conditions upon which
       the LTCP will be based.
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                 EXHIBIT 3-2.  EXAMPLES OF THE NINE MINIMUM CONTROLS
     Control Requirements/Purpose
                Examples of Control Measures
  Control Requirement:  Conduct proper
  operation and regular maintenance
  programs for the CSS and the CSO
  outfalls.

  Purpose: To reduce pollutant loading
  in CSOs and optimize the ability of the
  CSS to contain wet weather flows.  The
  Operation and Maintenance (O&M)
  program should address the CSS, CSO
  outfalls, and any treatment facilities
  installed for CSO control.
Schedule and conduct routine inspections and maintenance/cleaning
of sewer system and CSO controls; emphasize operations in areas
of heavy use, high pollutant loads, and sensitive components.

Flush or clean sewer during dry weather to eliminate solids
carrying a high pollutant load from being discharged with the  first
flush.  (This may not be practical for larger sewers.)  An
automatic flushing system is encouraged.

Conduct regular inspections of and maintain regulators, tidegates
and overflow devices, looking for damage, corrosion, and
clogging.

Budget for, schedule, and conduct repair activities to reduce or
eliminate infiltration or  maintain integrity of sewer structure.

Develop an operation and maintenance reporting and recordkeeping
system, which includes  maintenance procedures and inspection
reports.

Identify and eliminate unauthorized connections.

Train inspection and maintenance  personnel.
  Control Requirement:  Maximize use
  of the collection system for storage.

  Purpose:  To reduce the frequency and
  quantity of CSOs by storing wastewater
  in the existing conveyance system so it
  can be routed to the treatment plant for
  eventual treatment.
Store wet weather flow in the CSS or interceptors. (This measure
may increase the possibility of flooding.)

Clean out solids that have settled in the collection system to
increase storage capacity.

Construct detention basins, ditch drains, and street catch basins to
increase storage.

Disconnect roof leaders or reroute to splash pads with drainage to
dry wells, manmade pervious areas, or  street catch basins.

Construct "speed humps" to direct street flow (overland flow)
away from sensitive areas and into storage capture areas.
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                 EXHIBIT 3-2.  EXAMPLES or THE NINE MINIMUM CONTROLS (continued)
     Control Requirements/Purpose
                Examples of Control Measures
  Control Requirement:  Review and
  modify pretreatment programs to ensure
  that CSO impacts are minimized.

  Purpose:  To ensure CSO impacts from
  industrial discharges are minimized.
Identify and evaluate industrial user discharges to the same water
body as the CSO outfalls.

Review CSO monitoring results to identify and control industrial
pollutants in CSOs.

Restrict the addition of new or increased volumes of industrial
process or high-strength wastewaters into the sewer system under
circumstances where they could be discharged through a CSO
point.

Enact local sewer use ordinances or revise individual control
mechanisms to control industrial discharges during wet weather.
 Control Requirement: Maximize flow
 to the POTW for treatment.

 Purpose:  To reduce the CSO volume
 and pollutant load by maximizing the
 volume of wet weather flows delivered
 to and treated in the wastewater
 treatment plant.
Review POTW design criteria and operating data to establish the
maximum daily and monthly flow rates that can be treated without
exceeding permit limits.

Use regulators, such as gates, weirs, and siphons, to divert the
maximum flow to the interceptors during wet weather.

Conduct plant tests to demonstrate the ability to treat higher wet
weather flows.

Evaluate possible modifications to the POTW to increase treatment
capacity during wet weather.

Consider  using abandoned units during wet weather.

Regulate the amount of septage that can be accepted during wet
weather periods.
 Control Requirement: Prohibit CSOs
 during dry weather.

 Purpose:  To ensure CSOs are
 prevented during dry weather through
 the use of maintenance and repair
 procedures and revisions to the CSS.
Identify dry weather overflow locations and determine the cause.
Take immediate corrective action to eliminate overflows through
maintenance and repair or other non-major construction.

Develop and implement a plan to eliminate all dry weather
overflows (may  include relocation of outfalls or modification of
overflow appurtenances).

Promptly notify permitting authority of overflow.
 Control Requirement:  Control solid
 and floatable materials in CSOs.

 Purpose:  To control the discharge of
 solids and floatable materials.
Attach nets at the end of pipes.

Street sweeping.

Install bar screens and booms at CSO outfalls.

Recycling of materials.
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                         EXHIBIT 3-2.  EXAMPLES OF THE NINE MINIMUM CONTROLS (continued)
              Control Requirements/Purpose
                                                     Examples of Control Measures
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Control Requirement: Develop and
implement pollution prevention
programs that focus on contaminant
reduction activities.

Purpose:  To focus on source control
activities that reduce the amount of
contaminants in CSOs.
Develop a public education program detailing recycle/reuse, water
conservation practices, and ways to reduce the disposal of toxic
contaminants from household sources.

Develop used oil recycling program.

Institute best management practices,  such as increased or targeted
street sweeping/cleaning, catch basin cleaning, and construction
site erosion control.

Promote an anti-Utter campaign.

Encourage the community to ban the sale of certain products.
Control Requirement:  Notify the
public.

Purpose:  To ensure that the public
receives adequate notification of CSO
occurrences and CSO impacts on
receiving water bodies.
Install and maintain signs at CSO locations.

Announce use restrictions on television and radio and in
newspapers.
Control Requirement:  Monitor to
effectively characterize CSO impacts
and the efficacy of CSO controls.

Purpose:  To provide the permittee and
permit writer with data essential to
establishing the baseline conditions
needed to evaluate the efficacy (i.e.,
environmental effectiveness) of CSO
controls and to develop the LTCP.

(The permittee's monitoring program in
response to this requirement could be
integrated with the monitoring efforts to
characterize its CSS in the development
of the LTCP.)
Identify overflow locations, receiving water bodies, and use areas.

Maintain records of the volume and duration of overflow
occurrences, impacts, and characteristics, and the associated
amount of rainfall.

Monitor and report water quality impacts from CSOs on the
receiving waters.

Monitor and report beach and shellfish bed closures and swimming
restrictions due to CSOs.
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    •  Reporting on implementation.  Reporting will include the submission of appropriate
       documentation to illustrate implementation of the NMC.
3.4.1  Implementation Considerations
    Because the compliance date contained in the CWA for technology-based requirements has
passed, the permit writer should require the NMC to be implemented immediately. When the
permittee cannot  comply, the permit writer should coordinate with appropriate enforcement
authority staff to prepare an enforcement order,  including a fixed date compliance schedule. The
CSO Control Policy requires implementation of the NMC as soon as practicable, but no later
than January  1,   1997.    Exhibit  3-3  provides  example  permit language  for  requiring
implementation of the NMC. The permit writer should carefully evaluate this language to ensure
that it  is appropriate for the permittee.   The permit writer must also prepare a fact sheet or
statement of basis associated with the implementation of the NMC. The permit writer must
show that the permittee's NMC satisfy the BAT/BCT requirements based on BPJ of the permit
writer, in accordance with NPDES regulations.  For additional details on the use of BPJ, refer
to Section 4.4.2 of this manual and to the Training Manual for NPDES Permit Writers (EPA,
1993).

    When the permittee is already implementing some or all of the NMC, the permit writer may
want to customize the permit language to address site-specific conditions. For example, if the
permittee is already implementing an O&M program, the permit writer might craft language that
specifically addresses  inspection frequency. If the permittee is already controlling solid and
floatable materials, the permit writer may augment the example language to address the specific
controls being implemented. Section 4.4.2 addresses site-specific guidance in greater detail.
In any event, the permit writer should ensure that the permit language is consistent with the CSO
Control Policy and is enforceable.

    In the case where the permittee does not have an approved pretreatment program under 40
CFR Part 403, the permit writer should require the permittee  to minimize discharges  from
nondomestic users within the CSS prior to CSOs.  Alternative language for this option is
presented in Exhibit 3-3.
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                            EXHIBIT 3-3. EXAMPLE PERMIT LANGUAGE FOR
               REQUIRING IMMEDIATE IMPLEMENTATION OF THE NINE MINIMUM CONTROLS
  I. Effluent Limits

  A.  Technology-based requirements for CSOs.  The permittee shall comply with the following technology-
      based effluent limits in the form of narrative controls:

      1.  The permittee shall implement proper operation and maintenance programs for the sewer system and
         all CSO outfalls, with consideration given to regular sewer inspections; sewer, catch basin, and
         regulator cleaning; equipment and sewer collection system repair or replacement, where necessary;
         and disconnection of illegal  connections.

      2.  The permittee shall implement procedures that will maximize use of the collection system for
         wastewater storage.

      3.  The permittee shall review and modify, as appropriate, the existing Pretreatment Program to
         minimize the impact of nondomestic discharges from CSOs.

         [Alternative language for permittees without an approved Pretreatment Program] The permittee
         shall take steps to minimize the impact of nondomestic discharges from CSOs.

      4.  The permittee shall operate the POTW treatment plant at maximum treatable flow during all wet
         weather flow conditions.  The permittee shall deliver all flows to the treatment plant within the
         constraints of the treatment capacity of the POTW.

      5.  Dry weather overflows from CSO outfalls are prohibited.  All dry weather overflows must be
         reported to the permitting authority as soon  as the permittee becomes aware of the overflow. When
         the permittee detects a dry weather overflow, the permittee shall begin corrective action immediately.
         The permittee shall inspect the dry weather  overflow each subsequent day until the overflow has
         been eliminated.

      6.  The permittee shall implement controls to remove solid and floatable materials in its CSOs.

      7.  The permittee shall implement a pollution prevention program focused  on reducing the impact of
         CSOs on receiving waters.

      8.  The permittee shall implement a public notification process to inform citizens  of when and where
         CSOs occur. The process must include (a) a mechanism to alert persons of the occurrence  of CSOs
         and (b) a system to determine the nature and duration of conditions that are potentially harmful for
         users of receiving waters due to CSOs.

      9.  The permittee shall monitor CSO outfalls to effectively characterize CSO impacts and the efficacy of
         CSO controls. This information will be used to establish the existing baseline  conditions, evaluate the
         efficacy of the CSO  technology-based controls, and determine the baseline conditions upon which the
         long-term control plan will be based. These data shall include:

         a.   All CSO outfalls in the  CSS
         b.   Total number of CSO events and the frequency, duration, volume, and pollutant loadings of
             CSOs during each event
         c.   Water quality data for receiving water bodies
         d.   Water quality impacts (e.g., beach closings, floatables wash-up episodes,  fish kills).

         Monitoring for duration, volume, and pollutant loadings during each overflow event shall occur at a
         representative number of CSOs.
Working Draft
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 3.4.2  Documentation and Reporting
    The Phase I permit should contain requirements for the permittee to submit documentation
 demonstrating the implementation of each NMC.  The CSO Control Policy recommends this
 documentation be submitted as soon as possible but no later than 2 years after the issuance of
 the NPDES permit.  The purpose of the documentation is to 1) verify that the permittee has
 evaluated,  selected, and implemented CSO controls for each NMC, 2) establish the existing
 baseline conditions, evaluate the efficacy of the CSO technology-based controls, and determine
 the baseline conditions upon which the LTCP will be based, and 3) evaluate the degree to which
 the NMC achieve compliance with WQS.

    The documentation of NMC implementation must  be adequate to verify that the permittee
 evaluated and selected the most appropriate control measure for each NMC.  To determine
 whether the permittee has properly conducted the evaluation and selection process, the permit
 writer should require the submittal of certain documents, including the ones listed in Exhibit 3-4.
 Exhibit  3-4  presents  example  permit  language requiring  documentation  for  each  NMC.
 Combined  Sewer Overflows—Guidance for Nine Minimum  Control Measures  (EPA,  1994)
 contains examples of the types of documentation for each NMC.  The permit writer should note
 that the documentation required in Exhibit 3-4 may come in a variety of forms.  For example,
 the permittee may submit reports and studies prepared  for other purposes, such as operating or
 facility plans, revised sewer use ordinances, sewer system inspection reports, technical studies,
 and pollution prevention program plans; public notification plans; and contracts and schedules
 for minor construction programs for improving the existing system's operation.

    Another option for the permit writer is to require periodic reports on implementation of the
NMC throughout the term of the permit. For example, the permit writer may require updates
 of any significant changes in NMC implementation by the permittee.  In addition, the permit
writer may require the submission of monitoring data  at a specified frequency throughout the
term of the Phase I permit.
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                       EXHIBIT 3-4.  EXAMPLE PERMIT LANGUAGE  FOR
     REQUIRING DOCUMENTATION AND REPORTING OF THE NINE MINIMUM CONTROLS
  n.  Reporting Requirements

  A.  Nine minimum CSQ control reporting.  The permittee shall submit documentation that demonstrates
      implementation of each of the nine minimum CSO controls that includes the elements contained in
      Sections II.A.I through II.A.9 below. The permittee shall submit this documentation to the permitting
      authority on or before [insert due date].

  1.   Proper operation and regular maintenance programs. The permittee shall submit:

      a.  Identification of CSS components requiring routine operation and maintenance
      b.  Evaluation of operation and maintenance procedures to include regular inspections; sewer, catch
         basin, and regulator cleaning; equipment and sewer collection system repair or replacement where
         necessary
      c.  Operation and maintenance manual and/or procedures for the CSS and CSO structures
      d.  Resources allocated (manpower, equipment, training) for maintenance of the CSS and CSO
         structures
      e.  Summary of inspections conducted and maintenance  performed.

  2.   Maximization of the sewer collection system storage. The permittee shall submit:

      a.  Analysis/study of procedures to maximize collection system storage
      b.  Description of procedures in place for maximizing collection system storage
      c.  Schedule for implementation of minor construction associated with maximization of collection system
         storage
      d.  Documentation of actions taken to maximize storage
      e.  Identification of any additional potential actions to increase storage in the existing collection system,
         but which  require further analysis.  Confirmation that they will be/were evaluated in hydraulic
         studies conducted as part of the long-term control plan.

  3-   Review and  modification of controls on nondomestic sources. The permittee shall submit:

      a.  Results of an inventory of nondomestic discharges and assessment of the impact of such discharges
         on CSOs
      b.  Identification and analysis of feasibility of modifications to nondomestic source controls to reduce
         the impact of such discharges on CSOs
      c.  Documentation of selected modifications.

  4.   Maximization of flow to the POTW treatment plant for treatment. The permittee shall submit:

      a.  Study/analysis of existing conditions and  a comparison with the design capacity of the overall facility
      b.  Results or status of any engineering studies to increase treatment of wet weather flows
      c.  Documentation of actions taken to maximize flow and the magnitude of increase obtained or
         projected.

  5.   Elimination of CSOs during dry weather flow conditions. The permittee  shall submit:

      a.  Summary of dry weather overflows that occurred
      b.  Description of procedures for notifying permitting authority of dry weather overflows
      c.  Summary of actions  taken to identify dry weather overflows and progress toward eliminating  dry
         weather overflows.
Working Draft
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                          EXHIBIT 3-4.  EXAMPLE PERMIT LANGUAGE FOR
       REQUIRING DOCUMENTATION AND REPORTING OF THE NINE MINIMUM CONTROLS (continued)
  6.  Control of solid and floatable materials in CSOs. The permittee shall submit:


     a.  Engineering evaluation of procedures or technologies for controlling solids and floatable materials
     b.  Description of CSO controls in place for solids and floatable materials
     c.  Schedule for minor construction
     d.  Documentation of any additional controls to be installed or implemented.


  7.  Pollution prevention programs to reduce contaminants in CSOs.  The permittee shall submit:

     a.  Evaluation of pollution prevention opportunities to include procedures to control solid and floatable
         materials
     b.  Description of selected pollution prevention opportunities to include resources allocated for
         implementation
     c.  Documentation of pollution prevention program or actions taken.

  8.  Public notification. The permittee shall submit:


     a.  Evaluation of public notification options to include description of proposed and/or existing public
         notification procedures
     b.  Description of selected public notification methods
     c.  Log of CSO occurrences and associated  public notification.

  9.  Monitoring to characterize CSQ impacts and efficacy of CSO controls . The permittee shall submit:


     a.  Identification of CSO outfalls in the CSS
     b.  Summary of CSO occurrences  (total number of CSO events and frequency, duration, volume, and
         pollutant loadings of CSOs during events).  Monitoring summary for duration, volume, and pollutant
         loadings during each overflow event  may portray a representative number of CSOs.
     c.  Summary of water quality data for receiving water bodies
     d.  Summary of receiving water impacts (e.g., beach closings, floatables wash-up episodes, fish kills,
         etc.).
3.5    LONG-TERM CONTROL PLAN

    The second major element of the Phase I permit is the requirement to develop an LTCP that

will ultimately result in compliance with CWA requirements. The LTCP development process

is a comprehensive planning effort designed to evaluate a range of CSO control alternatives and

result in the selection of CSO controls that will contribute to the attainment of WQS.


    The LTCP development process will be an incremental and, frequently, a sequential process.

For example, a permittee must assess the impacts of CSOs on water quality prior to identifying

a range of feasible CSO  control  alternatives.  In establishing the requirements to develop an
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LTCP, the permit writer should consider the particular situation for each permittee.  In a limited
number of cases, the NMC may be sufficient to achieve WQS and the development of an LTCP
may not  be necessary.   In other cases, the municipality may have already begun the  CSO
planning process and the requirement to develop an LTCP should be tailored to reflect ongoing
efforts.

    This section provides guidance for the permit writer on how to require development of the
LTCP in accordance with the CSO Control Policy.  Section 3.5.1 describes each element of the
LTCP; Section 3.5.2 presents schedules for development of the LTCP; and Section 3.5.3
discusses considerations for small systems and ongoing CSO control efforts.  Permit writers
should refer to the Combined Sewer Overflows—Guidance for Long-Term Control Plan (EPA,
1994) for technical guidance on the development of LTCPs.

3.5.1  Components of the Long-Term Control Plan
    The CSO Control Policy outlines the following LTCP components:

    *   Public participation
    •   Characterization, monitoring,  and modeling of the CSS and receiving waters (including
       consideration of  sensitive areas)
    •   Evaluation and selection of alternatives
    •   Cost/performance considerations
    •   Operational plan
    •   Maximization of treatment at the POTW treatment plant
    •   Implementation schedule
    •   Post-construction compliance monitoring program.

    In general, the permit conditions requiring LTCP development should guide the development
of the LTCP consistent with the CSO Control Policy, establish distinct incremental actions,
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  1     provide the permittee flexibility in conducting the planning process, and ensure enforceability
  2     of subsequent permit conditions.
  3
  4        Exhibit 3-5 provides example permit language requiring the development of an LTCP.  The
  5     permit conditions in this exhibit include all the  components of an LTCP outlined in the CSO
  6     Control Policy.  Specific LTCP components should be listed in the permit rather than simply
  7     requiring the permittee to develop an LTCP consistent with the CSO Control Policy. A simple
  8     permit condition  such as, "The permittee shall complete and submit to the permitting authority
  9     an LTCP by  [date  specified}" may result in a permittee meeting this  permit condition by
10     submitting an incomplete or poorly developed plan.  Listing the components of the plan in the
11      permit condition requires the permittee to consider all of the necessary components of an LTCP.
12
13     Public Participation
14        The CSO Control Policy states the permittee should employ a public participation process
15      that "actively involves the affected public in the decision-making to select the long-term CSO
16     control(s)."  According to the  CSO Control Policy, the affected public includes rate payers,
17     industrial users of the sewer system, persons located on water bodies affected by the CSOs, and
18      any other interested persons.  Public participation is considered critical to the ultimate success
19      of the CSO controls selected by the permittee given the potential financial impact to the affected
20      public. Early and constant public participation during the development, evaluation, and selection
21      of CSO controls should reduce the potential for delays in the development of the plan, evaluation
22      of control alternatives,  and  implementation of  selected CSO controls, as well as avoid  the
23      unnecessary expenditure of resources by the permittee.
24
25         The permittee is  responsible for preparing and implementing the public participation plan.
26      The permit writer has two options for requiring public participation as a part of LTCP
27      development:
28
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                       EXHIBIT 3-5.  EXAMPLE PERMIT  LANGUAGE  FOR
              REQUIRING THE DEVELOPMENT OF A LONG-TERM  CONTROL PLAN
  III.      Long-Term Control Plan

  The permittee shall develop the long-term control plan that will include the elements contained in Sections
  III.A through III.D below and  shall  submit the plan elements in accordance with the schedule contained in
  Section ni.E:
  A.  Public Participation

      The permittee shall prepare and implement a public participation plan that outlines how the permittee will
      ensure  participation  of the public throughout the long-term control  plan development process.   For
      purposes of this permit,  the public includes, but is not limited to, rate payers, industrial users of the sewer
      system,  persons who reside near water bodies affected by the  CSOs, people who use and enjoy  these
      affected waters, and any other interested persons.  In developing the plan, the permittee shall consider the
      use of mechanisms such as public meetings throughout the process of developing a long-term control plan,
      including the process of selecting the long-term CSO controls. The long-term control plan shall include a
      summary of each of the major public participation events.
  B.  CSS Characterization

      The permittee shall develop and implement a plan that will result in  a comprehensive characterization of
      the CSS developed through records review, monitoring,  modeling, and other means  as appropriate to
      establish the existing baseline conditions, evaluate the efficacy of the CSO technology-based controls, and
      determine  the  baseline  conditions upon which  the  long-term  control  plan  will  be based.   The
      characterization shall adequately address the response of the CSS to  various precipitation events; identify
      the number, location, frequency,  and  characteristics of all  CSOs; and identify water quality impacts that
      result from all CSOs.

      To complete the characterization, the permittee shall employ the  following methods:

          1.   Rabfall  Records Review. The  permittee shall examine the  complete  rainfall records for the
              geographic areas of the CSS and evaluate the flow variations in the receiving water body to
              correlate between the CSOs and receiving water conditions.

         2.   CSS Records Review.  The  permittee shall review and evaluate all available  CSS records and
              undertake field inspections and other necessary activities to identify the number, location, and
              frequency of CSOs and their location relative to sensitive areas (as identified in III.B.4) and to
              pollution sources, such as significant industrial  users, in the collection system.

         3.   CSO Monitoring.  The permittee shall develop and submit a monitoring program that measures
              the frequency,  duration,  flow rate, volume, and pollutant concentration of CSOs and assesses the
              impact of the  CSOs on receiving waters.   Monitoring shall  be performed at a representative
             number of CSOs for the  following parameters:  [insert pollutants or concern (e.g.,  biochemical
             oxygen demand, total suspended solids)].  The monitoring  program  shall include  CSOs and
             ambient receiving water body monitoring and, where appropriate, other monitoring protocols,
             such as biological assessments, toxicity testing, and sediment sampling.
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                             EXHIBIT 3-5. EXAMPLE PERMIT LANGUAGE FOR
               REQUIRING THE DEVELOPMENT OF A LONG-TERM CONTROL PLAN (continued)
          4.   Identification of Sensitive Areas.  The permittee shall  identify sensitive areas to which its CSOs
              discharge.  These  areas  shall include outstanding national resource  waters,  National Marine
              Sanctuaries,  waters with threatened or endangered species and their designated critical habitat,
              waters  designated for primary contact recreational  use, public drinking water intakes or their
              designated protection areas, shellfish beds, and any other areas  identified by the permittee or
              permitting authority, in coordination with appropriate State or Federal agencies.

          5.   Modeling. The permittee may [shall] employ models, which include appropriate calibration and
              verification with field measurements, to  aid in the characterization.  If models are used,  they
              shall be identified by  the permittee along  with an explanation of why the model was selected and
              used in the characterization.

  C.  CSO Control Alternatives
      1.   Development  of  CSO Control Alternatives.  The  permittee shall develop a range of CSO control
          alternatives that would be necessary to achieve [insert levels of control, such as zero  overflow
          events  per  year, an average  of  1 to 3, 4  to 7, and 8 to 12 overflow events per year].  The
          permittee shall also consider expansion of the POTW treatment plant secondary and primary capacity
          as an alternative.
          Alternatives presented must give the highest  priority to controlling CSOs to the following sensitive
          areas, identified in  ffl.B.4.  For such  areas,  the alternatives included in the plan must (1) prohibit
          new or significantly  increased CSOs,  (2) eliminate or relocate CSOs  from such areas wherever
          physically and economically achievable, except where elimination or relocation would provide less
          environmental  protection  than additional  treatment,  (3)  where elimination  or  relocation  is  not
          physically or economically achievable or would provide less environmental protection than additional
          treatment, provide the level of treatment for remaining CSOs deemed necessary to meet water quality
          standards for full  protection of existing and designated uses.
      2.   Evaluation  of  CSO Control  Alternatives.   The permittee shall evaluate  each  of the alternatives
          developed in accordance with III.C.I to select the CSO controls that will ensure  compliance with
          CWA requirements.

      3.   Cost/Performance Considerations.  The permittee shall develop and submit cost/performance curves
          that demonstrate the relationship among and the cost effectiveness of the CSO control alternatives.

  D.  Selected CSO Controls

  Once the permittee has selected the CSO controls in consultation with the permitting authority, the permittee
  shall submit the following:

      1.   Implementation Schedule.   The permittee shall submit a construction schedule and financing plan for
          the selected CSO controls as part  of the implementation schedule.   Such schedules may be phased
          based on the  relative importance  of the adverse  impacts on water quality standards and on  the
          permittee's financial capability.
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                            EXHIBIT 3-5.  EXAMPLE PERMIT LANGUAGE FOR
               REQUIRING THE DEVELOPMENT OF A LONG-TERM CONTROL PLAN (continued)
      2.   Operational Plan.  The permittee shall submit a revised operation and maintenance plan that addresses
          implementation of the selected CSO controls.  The revised operation and maintenance plan shall
          maximize the removal  of pollutants during and after each precipitation event using all available
          facilities within the collection and treatment system.
      3.   Post-Construction Compliance Monitoring Program.  The permittee shall develop and submit a post-
          construction monitoring program that (a) is adequate to ascertain the effectiveness of the CSO controls
          and (b) can be used to verify compliance with water quality standards.   The program shall include a
          plan that details the monitoring protocols to be followed, including effluent and ambient monitoring
          and, where appropriate, other monitoring protocols,  such as biological assessments, whole effluent
          toxicity testing, and sediment sampling.
  E.  Schedule and Interim Deliverables

  The following reports shall be  developed in accordance with the requirements specified in Sections ID.A
  through III.D and submitted to the permitting authority by the dates specified below:

      1.   Public Participation Plan, as required in Section  III.A, shall be submitted on or before  [insert due
          date].

      2.   CSS Characterization Monitoring and Modeling Plan,  as required in Section in.B, shall be submitted
          on or before [insert due date].

      3.   CSS Characterization Monitoring and Modeling Results, including identification of sensitive areas, as
          required in Section III.B, shall be submitted on or before [insert due date].

      4.   CSO Control Alternatives Identification, as required  in Section HI.C.I,  shall  be  submitted  on  or
          before [insert due date].

      5.   CSO Controls Evaluation and Cost Performance Curves for the selected CSO controls, as required in
          Sections IH.C.2 and 3, shall be submitted on or before [insert due  date],

      6.   Implementation Schedule, as required in Section III.D. 1, including  the affordability analysis,  shall be
          submitted on or before [insert due date].

      7.   Operational Plan revised to reflect selected CSO control alternatives, as required in Section ffl.D.2,
          shall be submitted on or before [insert due date].

      8.   Post-Construction Compliance Monitoring Program,  as required in Section III.D.3, shall be submitted
          on or before [insert due date].
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  1         •  Requiring the development of a public participation plan at the beginning of the planning
  2            process that describes how the  public will be involved throughout the  process of
  3            developing the LTCP.  In  this case, the permit writer should require the plan to be
  4            submitted to  the  permitting authority for  review.  This approach  is recommended;
  5            example permit language is provided in Exhibit 3-5.
  6
  7         •  Generally requiring public participation  and periodic  reporting  of  the  actual public
  8            involvement activities. Alternatively, the permit writer may require reporting at the end
  9            of the planning process when the permittee submits its final LTCP.
 10
 11
 12         Regardless  of the  option selected, the permit writer may want  to specify the type of
 13      documentation  that should be maintained  on public involvement.   For example, acceptable
 14      documentation  might cover public meetings (recording the date, time, location, approximate
 15      number of people attending, and key issues).  Acceptable documentation  may also include
 16      summaries of all public comments received, but not transcripts of all meetings.
 17
 18      Characterization, Monitoring, and Modeling of the CSS and Receiving Waters
 19         Characterization,  monitoring, and modeling activities provide the basis for the permittee to
20      choose and design effective CSO controls.  According to the CSO Control  Policy, the major
21      elements include:
22
23         •  Examination of rainfall records
24         •  Characterization of the CSS
25         *  Monitoring of CSOs and receiving water quality
26         •  Identification of sensitive areas
27         •  Modeling of the CSS and the receiving water.
28
29         As discussed  in Section  3.7, the permittee will be collecting initial characterization and
30      monitoring data as part of the requirement to implement the NMC (i.e., monitor to effectively
31      characterize CSO impacts and efficacy of CSO controls).   If the permittee has already
32      characterized its CSS, CSOs, and impacts on receiving waters, permit requirements for further
33      characterization may  not  be necessary.  If the permittee has not sufficiently characterized the
34      system, the permit writer should  determine  any  further efforts needed  and establish permit
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conditions that specify the monitoring activities the permittee should conduct to adequately
complete this component of the LTCP.  The permit writer should refer to the Combined Sewer
Overflow Modeling and Monitoring Guidance (EPA, 1994) and the Combined Sewer Overflows-
Guidance for Long-Term Control Plan (EPA, 1994) for technical guidance related to proper CSS
characterization.

    It is recommended that the permit writer require the permittee to develop a characterization
and monitoring plan that includes the monitoring protocols and procedures that will be used to
characterize the CSS. Submission  of the plan by  the permittee prior to implementation, and
subsequent review and concurrence by the permit writer, will assist in ensuring that adequate
characterization data are collected by the permittee.

Identification of Sensitive Areas
    The identification of sensitive areas should be commenced as part of the CSS characterization
as soon as the locations of all CSOs are known. The CSO Control Policy identifies the type of
sensitive areas that should  be given  priority during  LTCP development.  Exhibit 3-6 lists these
sensitive areas.

    The determination of sensitive areas should be  made by the permittee in consultation with
the NPDES permitting authority  and may require coordination with local,  State,  and Federal
agencies involved in the protection of such areas.  For example, the permittee and permit writer
should coordinate with the U.S. Fish and Wildlife Service to determine whether CSOs discharge
to waters with threatened or endangered species.  The permittee should also coordinate with the
local public water utility to ensure the designation of drinking water sources as sensitive areas.
The permittee should evaluate the designated uses of each  CSO receiving water  because the
designations indicate a receiving water is sensitive (e.g., when receiving waters are designated
for primary contact recreation protection).
         Working Draft
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April 6, 1994

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       EXHIBIT 3-6.  SENSITIVE AREAS IDENTIFIED IN THE CSO CONTROL POLICY
        Outstanding National Resource Waters
        National Marine Sanctuaries
        Waters with threatened or endangered species and their designated critical habitat
        Waters designated for primary contact recreational use (such as swimming)
        Public drinking water intakes or their designated protection areas
        Shellfish beds
Evaluation of Alternatives
   The intent of the LTCP is to evaluate CSO control alternatives that will enable the permittee,
in consultation with the NPDES permitting authority, WQS authority, and the public, to select
CSO controls that will meet CWA requirements.  To ensure that the most cost-effective and
protective CSO controls are selected, the permit writer should require the permittee to consider
a reasonable  range  of CSO control alternatives.   The  CSO Control  Policy encourages the
permittee to evaluate CSO control alternatives that provide varying levels of controls.  The CSO
Control Policy suggests the permittee evaluate CSO control alternatives that would be necessary
to achieve, for example, the following levels of control:

   •   Zero overflow events per year (e.g., total elimination of CSOs via storage and/or sewer
       separation)
   •   An average of  1 to 3 overflow events per year
   •   An average of 4 to 7 overflow events per year
   •   An average of 8 to 12 overflow events per year.

   The CSO control alternatives to be considered  should provide the required level of control
to achieve WQS.  For example, the CSO control alternatives could include total sewer separation
or retention of all combined sewer flows for  subsequent treatment during dry weather. Or, the
CSO control alternatives could include a combination of controls for an entire system  (e.g.,
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partial sewer separation and retention).  In addition, the permittee should consider, among its
CSO control alternatives, expanding POTW treatment plant secondary and primary capacity and
associated appurtenances to enable additional treatment of combined sewer flows.  Thus, the
Phase I permit  should require the permittee to evaluate the maximization of treatment at the
POTW treatment plant among its CSO control alternatives, including the feasibility of expanding
either primary treatment capacity or both primary and secondary treatment capacity.

    In accordance with the CSO Control Policy, the permittee should ultimately select CSO
controls, in consultation with the NPDES permitting authority, WQS authority, and the public,
that, when implemented, will comply with CWA requirements either through the "presumption
approach" or the "demonstration approach."  It is unlikely that a permittee or a permit writer
will be able to determine the level of control necessary to meet WQS  requirements prior to the
initiation of the LTCP planning process.  Likewise, a permittee will not be able to specifically
adopt either the "presumption"  or  "demonstration" approach until after the initial planning
process has begun and more is known about its CSS and CSOs. The two evaluation approaches
contained in  the CSO Control Policy (i.e., presumption and demonstration) are described in the
following discussion.   The  permit  writer should  also  refer  to the  Combined Sewer
Overflows—Guidance for Long-Term Control Plan (EPA, 1994) for additional technical guidance
on evaluating CSO control alternatives.

Presumption Approach
    The underlying assumption of the presumption approach is that if the planned CSO controls
meet certain performance criteria, there is a reasonable likelihood of achieving WQS. The
consideration of the presumption approach is acceptable where the level of control needed to
attain WQS is unknown and no data suggest the approach will not meet WQS.  This approach
is based on the  permittee  meeting one of the following criteria presented in the CSO Control
Policy:
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April 6, 1994

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    • No more than an average of four overflow events per year, provided that the permitting
      authority may allow up to two additional overflow events per year.  Thus, the permit
      writer may allow an average of four, five,  or six overflow events per year.   For the
      purpose of this criterion,  the CSO Control Policy defines an overflow event as "one or
      more overflows from a combined sewer system as the result of a precipitation event that
      does not receive the minimum treatment specified."

    • The elimination or capture  for treatment of no less than 85 percent  by volume of the
      combined sewage collected in the combined sewer system during precipitation events on
      a system-wide annual average basis. To properly implement this provision, the permittee
      must calculate the total volume entering the combined sewer during precipitation events
      on a system-wide annual average basis to determine the volume of combined sewage that
      must be captured or eliminated.

    • The elimination or reduction of no less than  the mass of pollutants  identified as causing
      WQS violations through the sewer system  characterization,  monitoring, and modeling
      effort for the  volume(s) that would be eliminated or captured for treatment, as described
      under the previous bullet.  Again, the permittee will be responsible for determining the
      appropriate volume of combined sewage that must be treated. In addition, the permittee,
      in consultation with the permit writer, must determine the specific pollutants and  their
      masses that will result in WQS violations.
   All combined sewer flows in the CSS remaining after implementation of the NMC and within

the first two criteria specified above should be required to receive the following treatment:


   •  Primary clarification for the removal of floatables and settleable solids

   *  Solids and floatables disposal

   •  Disinfection of effluent, if necessary, to meet WQS and protect human health, including
       removal of harmful disinfection chemical residuals, where necessary.


   For example,  if the permittee chooses to capture  85 percent by volume of the combined
sewage collected on a system-wide annual basis during precipitation events, these flows must
receive the above treatment.  The remaining 15 percent by volume should receive treatment to

the greatest extent practicable.
       Working Draft
                                         3-22
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In all cases, the selected CSO control program should be designed to allow for cost-effective

expansion or cost-effective retrofitting if additional controls are subsequently determined to be

necessary to meet WQS.


   The example permit language provided for the presumption approach in Exhibit 3-5 is based

on the language provided in the CSO Control Policy. However, the example permit language,

in addressing disinfection requirements,  specifically requires reduction of a pathogen indicator

(e.g., £. coli) to levels that will achieve WQS.  This example language assumes such a standard

exists. In addition, the example permit language assumes the control of harmful disinfection

products  (e.g., chlorine) is unnecessary. In both cases, the permit writer should customize the

disinfection requirements to appropriately comply  with State WQS.


Demonstration Approach

   As an alternative to the presumption approach, the permittee may choose to demonstrate that

the selected CSO controls,  when implemented, will be  adequate to achieve compliance with

CWA requirements. As presented in the CSO Control Policy,  an adequate demonstration must
include each of the following:


   •  The planned control program is adequate to meet WQS  unless WQS cannot be met as a
      result of natural background conditions or pollution sources other than CSOs.  The permit
      writer will need to coordinate with the  permittee  to determine the  natural background
      conditions and other pollution sources.

   •  The CSOs remaining  after  implementation of  the planned  control program  will  not
      preclude  the attainment  of WQS.  If WQS are  not  met in part  because of natural
      background conditions or pollution sources other than CSOs, a total maximum daily load
      (TMDL), including a wasteload allocation (WLA) and a load allocation, or other means,
      should be used by the permitting authority to apportion pollutant  loads to all source
      discharges.

   •  The planned control program will  provide the maximum pollution reduction benefits
      reasonably attainable including the cost/performance considerations below.

   •  The planned control  program is  designed  to allow cost-effective  expansion  or cost-
      effective retrofitting if additional controls are subsequently determined to be necessary to
      meet WQS.
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April 6, 1994

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  1        To help ensure that the demonstration by the permittee will be adequate, the permit writer
  2     should consider defining an adequate demonstration.  If the NPDES permitting authority has
  3     particular policies or procedures for evaluating water quality impacts,  then the permit writer
  4     should place these requirements in the permit.  For example, if State WQS include criteria for
  5     the protection of wildlife, aquatic life, and human health, then the permit writer should require
  6     an evaluation for compliance with all three criteria, assuming they all apply to the CSO receiving
  7     water. If natural background conditions or pollution sources other than CSOs are contributing
  8     to exceedances of WQS, then the permitting authority would be responsible for the development
  9     of a TMDL and the WLA for any CSOs. The permittee must then demonstrate compliance with
 10     the WLA established by the permitting authority.  In the absence of a TMDL for a pollutant or
 11      pollutants, the permit writer should coordinate with appropriate State water quality personnel to
 12      determine how a permittee  will demonstrate compliance with WQS in light of the other source
 13      of pollutants. The permit writer also should clearly specify what will constitute a reasonable
 14      effort  by the permittee to demonstrate the maximum pollution reduction benefits reasonably
 15      attainable.   The term  "reasonably attainable"  generally refers to the cost to implement the
 16      planned control program in relation to the pollution reduction benefit of the control program.
 17      For further guidance,  the permit writer should refer to the discussion on cost-performance
 18      considerations below and to the Combined Sewer Overflows—Guidance for Long-Term Control
 19      Plan (EPA, 1994).
20
21      Cost/Performance Considerations
22         For the CSO control alternatives being evaluated,  the permit writer  should require the
23      permittee to develop and submit  with the LTCP appropriate cost/performance curves for each
24      of the  alternatives. The purpose  of developing these curves is for the permittee to demonstrate
25      the relationship between the effectiveness of CSO control alternatives being considered and the
26      cost associated with  each.  Consistent with  the CSO Control Policy, the permittee should be
27      required to include an analysis discussing the point at which the increment of pollution reduction
28      achieved in  the receiving water diminishes compared to increased costs. These analyses will
29      ultimately help guide  the  selection of  CSO controls  by the permittee, NPDES permitting
30      authority, WQS authority, and the public. For detailed guidance related to the development and
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review  of cost/performance  curves, the permit  writer should  refer to  Combined  Sewer
Overflows—Guidance for Long-Term Control Plan (EPA, 1994).

Operational Plan
   The Phase I permit should include a requirement that, once the appropriate CSO controls are
selected, the permittee will revise the O&M plan developed as part of the NMC to include the
selected CSO controls.  As described in the CSO Control Policy, the operational plan should be
designed to maximize the removal of pollutants during and after each precipitation event using
all available facilities within the collection and treatment  system.  The operational plan should
also  specify methods to ensure that any flows in excess  of the volumes prescribed under the
presumption approach (i.e., flows in excess of 85 percent by volume of the combined sewage
collected in the CSS during precipitation events on a system-wide annual average basis) receive
treatment to the greatest extent practicable.  The permit writer should refer to Combined Sewer
Overflows—Guidance for Long-Term Control Plan (EPA, 1994) for further information on
technical considerations for permittees to use when revising their O&M program to account for
selected CSO controls.

Maximization  of Treatment at the POTW Treatment Plant
   As discussed in evaluation alternatives, the permittee should evaluate the maximization of
treatment at the  POTW treatment plant as part of the LTCP.  This  includes evaluating the
feasibility of expanding either  primary treatment capacity or both primary and secondary
treatment capacities. This component of the LTCP is distinguished from maximization of flow
to the POTW  for treatment,  one of the NMC.  The NMC control measure is focused on flow
to the treatment plant rather than flow at the treatment plant and is envisioned to include the use
of excess wet weather flow  capacity,  rather than the  construction  of additional treatment
capacity.

Implementation Schedule
   The permit  should require the permittee to  develop  and submit  a schedule  for the
implementation of the selected CSO controls. In particular, the permit writer should require the
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  1      permittee to  develop  construction  schedules and  financing plans that  will  ensure  timely

  2      implementation of the selected CSO controls.  These schedules may be phased depending on the

  3      permittee's financial capability and the relative importance of adverse impacts on WQS.

  4

  5         The proposed CSO implementation schedule, including construction schedules and financing

  6      plans, should  reflect:
  7
  8         •  Elimination of CSOs to sensitive areas as the highest priorities
  9
 10         •  Receiving water use impairment
 11
 12         •  Permittee's financial capability, including consideration of such factors as:
 13
 14            -  Median household income
 15            -  Total annual wastewater and CSO control costs per household as a percent of median
 16               household income
 17            -  Overall net debt as a percent of full market property value
 18            -  Property tax revenues as a percent of full market property value
 19            -  Property tax collection rate
 20            -  Unemployment
 21            -  Bond rating
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 23         •  Grant and loan availability
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 25         •  Previous and current residential,  commercial, and  industrial sewer user fees and rate
 26            structures
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 28         •  Other viable funding mechanisms and sources of financing.

 29

 30         For guidance related to scheduling and financial capability, the permit writer should refer

 31      to the Combined Sewer Overflow Long Term  Control Plan and Financial Capability Assessment
32      Guidances (EPA, 1994).

 33

34      Post-Construction Compliance Monitoring Program

35         The post-construction compliance monitoring plan should be submitted by the permittee as

36      part of the LTCP and  reviewed by the permit writer (see Section 4.5.2).  The permit writer
37      should require that this plan detail the  monitoring protocols to be followed, including the
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necessary effluent and ambient monitoring and, where appropriate, other monitoring protocols,
such as biological assessments, whole effluent toxicity testing, and sediment sampling.

    The monitoring plan should provide for ambient receiving water pollutant monitoring at
locations appropriate to determine receiving  water background concentrations and  CSO
contributions.  The types of pollutants and parameters to be analyzed, which will depend on the
WQS in the receiving water body,  may include chemical (e.g., biochemical oxygen demand,
total suspended solids, metals, oil and grease, herbicides, and pesticides), and biological (e.g.,
fish, benthic invertebrates, and zooplankton) parameters.

    It should be noted that construction of the selected CSO controls by some permittees may
extend over several permit terms.   It may be appropriate to defer all or some portions of the
post-construction monitoring plan development requirements to later permits when construction
of the CSO controls is complete.

3.5.2  Schedule for Development of the Long-Term Control Plan
    The permit writer should establish a deadline in the permit for completing and submitting
the LTCP.  According to the CSO Control Policy, this deadline should be within 2  years of the
effective date of the Phase I permit or other implementation mechanism. As stated in the Policy,
the permit writer may extend the deadline beyond 2 years for the submission of the plan on a
case-by-case basis to account for site-specific  factors that may complicate the planning  process
on the part of the permittee.  This deadline or a schedule should be included in an enforcement
mechanism  or in a permit enforceable under the CWA.

    The permit writer should also consider  establishing a periodic reporting  schedule  that
requires  the permittee to report on progress  related  to LTCP development.  These progress
reports should require a narrative description of progress made to date on each of  the primary
LTCP components, identification of problems that may  affect completion of the LTCP, and a
description  of  remedial  measures  to be taken when necessary.   Depending on  the specific
circumstances and complexity of the CSS, a permit writer may require submission of progress
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  1     reports on a regular basis (e.g., monthly, biannual), customize the schedule to track critical path
  2     components  (e.g.,  to  ensure public participation occurs early  in  the process  or that CSS
  3     characterization is  proceeding), and/or require the submission  of progress  reports at the
  4     completion of each component of the LTCP.
  5
  6        In addition, the permit writer should consider establishing interim deadlines and deliverables
  7     for various components of the LTCP to ensure adequate progress is being made by the permittee
  8     during the term of the permit.  Example permit language requiring the submission of interim
  9     deliverables is provided in Exhibit 3-5, presented earlier. The submission of interim deliverables
10     prior to completion  of the LTCP allows the permit writer an opportunity to  review critical
11      components of  the  LTCP early in the planning process and  avoids delay  in issuing the
12     subsequent Phase n permit due to the submission of inadequate information or  analyses.  It is
13     recommended that the permit writer require the submission of the following interim deliverables:
14
15        •  Public participation plan
16        *  CSS  characterization monitoring and modeling plan
17        •  CSS  characterization  monitoring and  modeling results  (including identification  of
18           sensitive areas)
19        •  Identification of CSO control alternatives
20        •  Evaluation of CSO control alternatives and cost/performance curves
21         •  Operational plan
22         •  Proposed implementation schedule,  including  affordability analyses
23         *  Post-construction compliance monitoring plan.
24
25         Upon receipt of an  interim deliverable, the permit writer will be responsible for its review
26      and for working closely with the  permittee to ensure that any inadequacies, problems, or issues
27      are addressed prior to submittal of the final LTCP and issuance of the Phase n permit.  Further
28      guidance related to the  responsibilities of the permit writer while reviewing interim deliverables
29      is provided in Section 3.10.
30
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   The specific deadlines specified in the permit will depend on the circumstances of the CSS
being permitted.   For example,  if a permit writer  requires the development of a  public
participation plan, a corresponding deadline should be included in the permit to complete the
plan, as well as to implement the plan, after review by the permitting authority.  In other cases,
the information, such as that needed to identify sensitive areas (i.e., CSS characterization data),
may not be available prior  to issuance  of the Phase I permit.  Due  to  the importance of
protecting sensitive areas, the permit writer should establish a deadline  for the submission of
information on sensitive areas early in the LTCP development process.

3.5.3  Considerations for Previous or Ongoing CSO Control Efforts and Small Combined
       Sewer Systems
   Generally, two special factors should  be considered by the permit writer when establishing
the requirements to develop the LTCP—the permittee's previous efforts to control CSOs and the
limited resources of small communities.

Recognition of Previous or Ongoing Efforts at Controlling CSOs
   There may be  instances when the permit writer will find that municipalities are at different
stages of CSO characterization and CSO control implementation.  Some municipalities have
already begun planning, monitoring, and implementing CSO controls in response to EPA's 1989
CSO Permitting Strategy and other initiatives.  For example, a municipality may have already
characterized its CSOs and evaluated water quality impacts and is in the process of constructing
CSO controls.

   The following types of efforts that  a permittee  may have undertaken  prior to  Phase I
permitting may require special consideration by the permit writer on a case-by-case basis:  1)
substantial completion of construction of CSO controls that appear to meet WQS, 2) CSO control
programs substantially developed or implemented pursuant to existing permits or enforcement
orders, and 3) completion of construction of CSO control facilities designed to comply with
WQS but that have failed to meet WQS.
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    If the  permit  writer has  determined that the permittee  has  "substantially  completed"
 construction of projects designed to meet WQS, the permit conditions for LTCP development
 may be modified to reflect these previous efforts.  The permit writer may not wish to require
 the initial planning and construction provisions of the LTCP.  The permittee, however, should
 be required to complete the components of the LTCP that may not have been addressed by the
 permittee's previous efforts, that are still relevant, including the O&M program development and
 the post-construction monitoring plan.  If subsequent monitoring shows that the WQS are not
 being met, then the permittee should be required to submit a revised CSO control plan in an
 enforceable order and the permit modified accordingly.

   If the permittee has substantially developed or is implementing a CSO control program but
 has not yet substantially completed construction of the selected CSO controls and the control
 program is expected to meet WQS and is consistent with the objectives of the CSO Control
 Policy, the permit condition for LTCP development should be modified.  In this case, the permit
 writer may not want to require the permittee to conduct further planning except for evaluation
 of sensitive areas and  financial capabilities and development of  a post-construction monitoring
 plan.

   If the permittee has previously constructed CSO facilities in  an effort to comply with WQS
 but has failed to meet the applicable standards because remaining CSOs were not addressed, the
permit writer may  consider these previous efforts when determining further CSO  control
planning activities. The previous construction of CSO control facilities, although not achieving
WQS, may mitigate the need to develop a complete LTCP.  In other cases, a permit writer may
 need to require the development of a complete, although abbreviated, LTCP (e.g., further CSS
characterization  may be needed or other alternative CSO controls identified and costs and
funding mechanisms developed).

Small System Considerations
   The CSO  Control Policy acknowledges that portions of the LTCP may prove to be difficult
to implement  for small municipalities.  Particularly, the CSO  Control Policy recommends that
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for CSSs in jurisdictions with populations under 75,000, the permit requirement to develop the
LTCP should reflect the capabilities of such "small" jurisdictions in preparing their plans.  With
limited resources, dollars spent on system  characterization,  modeling and monitoring, and
evaluation of alternatives may be better spent on financing the implementation of CSO controls.
The permit writer  will,  however, need to  ensure  that the permittee has gathered  enough
information to implement effective CSO controls. The permit requirements for developing a
plan should include consideration of sensitive areas, public participation in the  selection of the
CSO controls, and a post-construction compliance monitoring program sufficient to determine
whether WQS are attained.  However, the permit writer should be aware that smaller systems
may not be able to afford extensive monitoring requirements. In these cases, the permit writer
should be prepared to accept a less extensive monitoring program from a small municipality.

3.6    EFFLUENT LIMITATIONS
    The CWA requires that  both technology- and water quality-based effluent limitations be
established for all point source  discharges.  In general, the CSO Control Policy relies on the
implementation of various control practices as the means to regulate CSOs. At  least during the
early stages of Phase I permitting, therefore, the permit  writer will establish technology- and
water quality-based requirements in the form of narrative requirements.  This  recognizes that
the permit  writer will not have sufficient data or information to establish numeric effluent
limitations.  During subsequent CSO permitting phases as data and information related to the
CSOs  and  controls implemented by  permittees improve, the permit writer should consider
developing numeric effluent  limitations.

3.6.1 Technology-Based Requirements
    Section 301 of the CWA requires that technology-based effluent limitations be established
for all discharges  of pollutants.  For existing nonmunicipal dischargers, these technology-based
effluent limitations  must reflect the BAT/BCT for conventional, toxic, and nonconventional
pollutants.
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    NPDES permit provisions at 40  CFR Section 122.44(a)  require the establishment of
 technology-based effluent limitations for all pollutants discharged by nonmunicipal point sources
 that will be regulated under an NPDES permit. Because CSSs are not considered POTWs, they
 are not subject to secondary treatment standards.  According to 40 CFR Section 125.3(c), in the
 absence of national effluent guidelines  and standards for nonmunicipal discharges, technology-
 based effluent limitations are to be established on a case-by-case basis using the permit writer's
 BPJ.

    The CSO Control Policy recommends the use of a variety of controls (i.e., the NMC) in the
 form of BMPs to regulate CSOs. The use of BMPs in lieu of numeric technology-based effluent
 limitations is allowed under 40 CFR Section  122.44(k)(2)  where it is infeasible to calculate a
 numeric limit.   BMPs are considered particularly  applicable for CSOs due to the general
 unpredictability of a precipitation event's driven discharges in terms of the types, concentrations,
 and quantities of pollutants expected.

    As stated in the  CSO Control Policy, Phase I permits should at  least require that the
 permittee  "immediately implement BAT/BCT, which includes the nine  minimum controls, as
 determined on  a BPJ basis  by the permitting authority."  Thus, where the permit writer
 determines on a BPJ basis that the implementation of the NMC in Phase I and Phase n permits
 meets the technology-based requirements, he/she should not need to develop numeric technology-
based effluent limitations. Exhibit 3-3,  presented previously, provides example permit language
 requiring implementation of the NMC.

   If, at a later date, numeric technology-based effluent limitations are warranted for CSOs, it
is recommended that the permit writer refer to the EPA Training Manual for NPDES Permit
 Writers (EPA, 1993)  for guidance on developing limits on  a case-by-case basis using BPJ.

3.6.2 Water Quality-Based Requirements
   Section 301(b)(l)(C) of the CWA requires that water quality-based  effluent limitations be
established for  all point  source discharges  that will  affect  receiving water  quality after
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implementation of technology-based requirements.  Pursuant to the CWA, the NPDES permit
regulations at 40 CFR Section 122.44(d) require the establishment of water quality-based effluent
limitations in NPDES permits for all discharges that cause, contribute, or have the potential to
cause an exceedance of a numeric or narrative water quality standard.

    The proper characterization of CSOs to determine  whether numeric water quality-based
effluent limitations are necessary is expected to be extremely difficult for the permit writer in
the early stages of permitting CSOs. This difficulty stems from a variety of reasons, including
the  lack  of data (both  point source and  ambient)  for  all  pollutants of concern  (e.g.,
conventionals, toxics, and nonconventionals).

    As described  in the CSO Control Policy, Phase I permits should at least require that the
permittee "immediately comply with applicable WQS expressed in  the  form  of a  narrative
limitation." As previously described, a narrative requirement to comply with WQS is justified
for CSOs due to the general  lack of data and the dependence on the LTCP to provide the data
necessary to evaluate the  need for numeric water quality-based effluent limits.

    Exhibit 3-7 gives example permit language requiring  CSOs to comply with narrative WQS.
The specific narrative standards a permit writer should include as a permit condition will depend
on, and  should be consistent with, standards specified in  the State WQS.   Although State
narrative standards can be incorporated into the permit by reference, it is recommended that the
permit writer include the  specific narrative language in the permit to ensure that the permittee
understands exactly what  standards it must meet.

3.7 MONITORING
    The Phase I permit should require that monitoring activities be initiated so basic system
characterization information can be established. In addition, the permit writer should establish
standard  monitoring  conditions for determining the compliance of CSOs with WQS.   The
information collected during Phase I will ultimately be used as a foundation to develop the more
comprehensive monitoring program associated with the LTCP and the Phase n permit. During
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 the Phase I permit term, the permittee should monitor the following pollutants to facilitate the

 establishment of baseline conditions:  pH, total suspended solids, biochemical oxygen demand,

 fecal coliform, and oil and grease.  For detailed information on monitoring activities, the permit

 writer is  referred to the Combined Sewer Overflow Monitoring and Modeling Guidance (EPA,

 1994).
                     EXHIBIT 3-7. EXAMPLE PERMIT LANGUAGE FOR
        REQUIRING  COMPLIANCE WITH NARRATIVE WATER QUALITY STANDARDS
 I.  Effluent Limits


 B.  Water quality-based requirements for CSOs.  The permittee shall not discharge any pollutant at a level
     that could cause or contribute to a violation of [insert applicable State narrative standards] water
     quality standards.


     Site-Specific Language:


     All discharges covered by this permit shall be free from the following pollutants at levels that cause or
     contribute to a violation of water quality standards:


     I.  Floating debris, oil, grease, scum, foam, or other materials on the water surface that may create a
        nuisance condition, or that may in any way interfere with attainment and maintenance of designated
        uses of the water


     2.  Settleable solids, sediments, sludge deposits, or suspended particles that may coat or cover
        submerged surfaces and create a nuisance condition, or that may in any way interfere with
        attainment and maintenance of designated uses of the water

     3.  Any pollutants, including those of a thermal, toxic, corrosive,  bacteriological, radiological, or other
        nature, that may interfere with attainment and maintenance of designated uses of the water; may
        impart undesirable odors, tastes, or colors to the water or to aquatic life found therein; may
        endanger public health; or  may result in dominance of nuisance species.
    Phase I permit monitoring requirements are driven by several different objectives.  The CSO

Control Policy requires specific monitoring to characterize CSO impacts and to determine the

efficacy of CSO controls as part of the NMC. The CSO Control Policy also requires monitoring

as part of the LTCP development to comprehensively characterize the CSS.  In addition, the

permit writer should establish  monitoring requirements that  will aid in establishing baseline

conditions prior to and subsequent to implementation of the  NMC.  Where these monitoring

objectives overlap, the permit writer should coordinate the requirements into a comprehensive

permit condition.  Example permit language associated with the NMC monitoring requirements
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is presented in Exhibits 3-3 and 3-4 given previously. Example permit language associated with
the monitoring required to characterize the CSS was provided in Exhibit 3-5 also given earlier.

    In most cases, implementation of monitoring associated with the NMC and the LTCP is
sufficient for Phase I permits.  In  some cases, however, the permit writer may want to require
special characterization studies (e.g., if site-specific information implies that CSOs are causing
substantial  water quality impacts). These studies may include the following:

    •  Sediment studies
    •  Toxicity testing
    •  Biological assessment.

    This type of monitoring can be required as a short-term study special condition. Typically,
such a study is required in response to specific information indicating water quality is being
affected.  The permit writer may  want to develop permit conditions that require 1) a separate
monitoring plan to be developed for each special study, 2) the plan be submitted for review prior
to performing the monitoring, and 3) the submission of a final report to the permitting authority
within a specified time after the study's completion.

    The permit writer should review the monitoring plans carefully to ensure the design assures
that CSO information is correlated with water quality impacts;  otherwise, the results of the
studies may not provide conclusive evidence of the cause of impact. In addition, other studies
may be needed in conjunction with these special studies. For example, sediment studies may
not be  meaningful without a contaminant transport modeling study, and a bioassay performed
without toxicity data and CSO data may not provide meaningful results.

3.8    REPORTING
    The major categories of reporting  requirements related to  CSO controls that should  be
included  in  the  Phase I permit are  associated  with:   1) documentation  of the  NMC
implementation and 2) LTCP development. Section 3.4.2 provides example permit language and
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 a detailed discussion of the reporting requirements associated with the NMC.   Section 3.5
 discusses the recommended LTCP interim deliverables, the requirement to submit the completed
 LTCP, and associated example permit language.

    In  addition to  the CSO  control-related  reporting  discussed above, permittees should be
 required  to periodically report the results from any special monitoring studies  and/or from
 monitoring requirements established in the permit.

 3.9    SPECIAL CONDITIONS
    This section discusses two special conditions. The first, CSO-related bypass, should be used
 in certain limited circumstances to authorize bypasses under Section 122.41(m).   The second
 special condition, a reopener clause, should appear in every permit covering CSOs.

 3.9.1  CSO-Related Bypass
    Some POTW treatment plants may  have primary treatment capacity that significantly exceeds
 secondary treatment.  The CSO Control Policy recognizes that 40 CFR Section 122.41 (m) can
 be interpreted to allow an advance authorization of a CSO-related bypass in the NPDES permit
 to take advantage of the opportunity to provide at least primary treatment of wet weather flows.
 The CSO Control Policy envisions that the permittee would evaluate the feasibility of this as part
 of the LTCP.  As such, this  special condition is only likely to occur in the Phase n permit, if
 at all.  If the permit writer believes that a CSO-related bypass may be an effective CSO control
 available for use in the Phase I permit, however, he/she should require the permittee to submit
 the necessary information as  part of the permit application.  The permit writer should refer to
 Section 4.9.1 for a detailed discussion of the CSO-related bypass.

3.9.2  Permit Reopener Clause
   As with any NPDES permit, the permit writer should include an appropriate reopener clause.
The permit writer may  find that the generic reopener clause used in other NPDES permits is
 sufficiently broad to address CSOs.  Exhibit  3-8 provides a typical reopener clause appropriate
 for a Phase I permit.  The permit writer may  also consider including reopener language that
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allows the permit to be modified or revoked and  reissued to incorporate requirements to
implement selected CSO controls in the  LTCP (Phase II) in advance of the  normal permit
reissuance. This will assist the permit writer in accelerating the implementation of selected CSO
controls.
            EXHIBIT 3-8.  EXAMPLE PERMIT LANGUAGE FOR A PHASE I REOPENER CLAUSE
  This permit may be modified or revoked and reissued to comply with any State or Federal law or
  regulation that addresses CSOs and that is promulgated subsequent to the effective date of the
  permit, or if additional information indicates CSO controls fail to meet State water quality
  standards.
  Upon satisfactory completion of the long-term control plan, the permit may be modified or
  revoked and reissued to require implementation of the selected CSO controls.
  In addition, this permit may be modified or revoked and reissued for any other valid reason
  pursuant to 40 CFR §122.62.
3.10   ADDITIONAL AcrrvrnEs  DURING PHASE I PERMITTING
   The permit writer is responsible for ensuring the receipt and coordinating the review of the
NMC documentation and all interim CSO-related documents submitted as part of the LTCP
development.  The primary purpose of the review of NMC documentation and LTCP interim
deliverables is for the permit writer to begin evaluating the progress made by the permittee in
implementing the NMC and developing its LTCP. The early review during Phase I will assist
the permit writer in identifying and  resolving issues prior to the development of the Phase n
permit.  If the review of progress made by the permittee during the Phase I permit term is not
performed until just prior to the development of the Phase n permit, significant delays  may
occur,  particularly  if a  permit writer finds extensive deficiencies in the progress made by the
permittee.

   To  ensure  that  the  NMC documentation and all LTCP interim  deliverables are  properly
reviewed and to facilitate the expeditious  review of these submissions, the permit writer should
coordinate among appropriate  NPDES permitting authority  representatives.   As part of the
coordination process, the permit writer should decide who should review the NMC documenta-
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  1     tion and LTCP interim deliverables.  In most cases, the review team should include NPDES

  2     permitting and enforcement representatives  and WQS authority representatives (see  Section

  3     4.5.1).  The permit writer should also contact the appropriate individuals to be part of the

  4     review team, disseminate information, coordinate the review of materials and meetings, and

  5     receive and integrate comments.  The review team may also be useful in assisting the permit

  6     writer in developing permit conditions.
  7

  8

  9     3.11   DEFINITIONS

10
11      Note to Reader:   These definitions are currently under development.  EPA is especially
12     interested in soliciting comments on this section of the guidance document.
13

14        As CSO-related permit conditions are incorporated into the permit, it also may be appropriate

IS      to expand the definitions section of the permit.  A list of terms that may be appropriate to

16     include in either the Phase I or Phase n permit (depending on where they are used as part of the

17     permit language) and their suggested definitions are listed below:

18
19         *  Average Number of Overflow Events Per Year—The total number of combined sewer
20            overflow events that occurred during the term of the permit divided by the permit term
21            in years.
22
23         •   Combined  Sewer Overflow—The discharge from a designated  outfall location of a
24            combined sewer system to the receiving water prior to reaching the publicly  owned
25            treatment works treatment plant.
26
27         •   Combined  Sewer Overflow Event—One or more combined sewer overflow  from a
28            combined sewer system as the result of a precipitation event. A separate combined sewer
29            overflow event will  have occurred  where the discharge  is  interrupted for  [insert
30            appropriate duration] or more hours.
31
32         •   Combined  Sewer  System—A  wastewater  collection system owned  by a State or
33            municipality (as defined by Section 502(4) of the Clean Water Act) that conveys sanitary
34            wastewaters (domestic, commercial, and industrial wastewaters) and storm water through
35            a single-pipe system  to a publicly owned treatment works treatment plant (as defined in
36            40CFR403.3(p)).
37
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•  Dry Weather Flow Conditions—Hydraulic flow conditions within the combined sewer
   system  resulting  from  the  flows  of domestic  sewage,  groundwater  infiltration,
   commercial and industrial wastewaters, and any other non-precipitation event related
   flows (e.g., tidal infiltration).
•  Dry Weather Overflow-
   flow conditions.
-A combined sewer overflow that occurs during dry weather
•  Precipitation Event—An occurrence of rain,  snow, sleet, hail, or  other generally
   recognized form of precipitation.  Precipitation events are characterized by parameters
   of duration (time) and intensity (inches or millimeters of precipitation). For the purposes
   of this permit, a precipitation event is defined as [0.25] or [insert appropriate measure]
   inches or more of precipitation in the form of rain or [3] or [insert appropriate
   measure] inches or more of precipitation in the form of sleet or snow,  reported during
   the preceding 24-hour period  at the [insert location of official precipitation gaging
   station(s)].

•  Primary Clarification or Equivalent—The level of treatment that would typically be
   provided by a municipal wastewater treatment plant under peak wet weather flow
   conditions.  The equivalent to primary clarification includes systems that achieve the
   following:  35 percent removal of influent total suspended solids (TSS), and 15 percent
   removal of influent 5-day biochemical oxygen demand (BOD5).

•  Sensitive Areas—Areas of particular environmental  significance or sensitivity that could
   be adversely affected by a combined sewer  overflow including,  but  not  limited to,
   Outstanding  National  Resource Waters,  National  Marine  Sanctuaries,  water with
   threatened or endangered species and their critical habitat, waters designated for primary
   contact recreational use,  public drinking water intakes or their designated protection
   areas,  shellfish beds, and other areas identified by the permittee or permitting authority,
   in coordination with the appropriate State or Federal agencies.

•  Solid and Floatable Materials—Solid or semi-solid material suspended or present in the
   water column that will not pass freely through a screen or mesh with openings of [insert
   appropriate mesh size] inches.

•  Wet Weather Flow Conditions—Hydraulic flow conditions within  the combined sewer
   system resulting from a precipitation event.
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                                     CHAPTER 4
                                PHASE n PERMITTING

    This chapter provides the permit writer with guidance related to developing and issuing the
Phase n permit. It also discusses the review and evaluation of documentation required by the
Phase I permit associated with implementation of the NMC and development of the LTCP.

4.1    PHASE n PERMIT PROCESS
    The primary objective of the Phase II permit is to require the permittee to implement the
selected CSO controls in the LTCP that will meet CWA requirements.  After the permittee has
completed the development of the LTCP and has discussed and coordinated the selection of the
necessary  CSO  controls with the permit writer, the  State WQS authority,  and the public, the
permit writer can proceed to embody the selected CSO controls into the Phase n permit.
   To be consistent with the CSO Control Policy, the Phase n permit should contain provisions
that:
    •   Require the permittee to continue implementing the NMC
    •   Direct the permittee to implement and properly operate and maintain the selected CSO
       controls from the LTCP
    •   Require the permittee to implement a post-construction water quality monitoring program
    •   Require the permittee to reassess  overflows to sensitive  areas where  elimination or
       relocation was not feasible
    •   Authorize the permitting authority to reopen and modify the permit when the CSO
       controls do not result  in attainment of WQS.
   The permit  writer should coordinate the development of the Phase n permit  with  the
permittee and the State WQS authority to ensure that statutory and regulatory requirements are
met. The permit writer should also ensure that the general public is involved in the  decision-
making process leading to finalization of the Phase n permit conditions through the public notice
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  I      provisions of the NPDES permit regulations or the equivalent provision in approved NPDES
  2      State permit issuance programs.
  3
  4         In drafting the Phase II permit, the permit writer should work closely with the permittee and
  5      the State WQS authority in reviewing the CSO control alternatives presented in the LTCP.  The
  6      permit writer  should ensure that the permittee has shown, using either the presumption or
  7      demonstration  approach, that the selected CSO controls will meet WQS in the receiving water
  8      body.
  9
10         For the technology-based requirements in  the Phase n permit, the permit writer should
11      require continued implementation of the NMC. The permittee's documentation may be used to
12      show that the  NMC continue to satisfy BAT/BCT requirements on the basis of the permit
13      writer's BPJ.  The permit writer may choose to modify any or all of the NMC from the Phase
14      I permit to be  more site-specific, based on the documentation submitted by the permittee.  For
15      the water quality-based requirements in the Phase n permit, the permit writer should require
16      implementation of the selected CSO controls the permittee has demonstrated or presumed will
17      achieve WQS.  The permit writer must document in the fact sheet or statement of basis that the
18      Phase n permit meets the technology-based and water quality-based requirements  of the CWA.
19
20      4.2    INFORMATION REQUIREMENTS
21         Existing NPDES application forms do not typically require the permittee to submit sufficient
22      information and data to enable the permit writer to develop a Phase II permit. The permit writer
23      must rely on information and data that the permittee has submitted in response to Phase I permit
24      requirements.  This includes 1) the documentation showing the permittee's implementation of
25      the NMC,  2)  the LTCP,  including  any interim  deliverables submitted during  the LTCP
26      development, and 3) any other information required by the Phase I permit. The permit writer
27      will need this  information,  at a minimum, to develop an  effective Phase n permit.  If this
28      information is  not adequate, the permit writer  should request additional information from the
29      permittee. The permit writer should refer to Section 3.2 for available mechanisms for obtaining
30      additional information and data.
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4.3    IDENTIFICATION OF CSO OUTFALLS IN THE PERMIT
    Prior to issuance of the Phase n permit, the locations of all CSO outfalls should be known.
Therefore, the permit writer should specifically identify CSO outfalls in the Phase n permit.
Exhibit 4-1 provides example permit language for authorization to discharge from CSO outfalls.
     EXHIBIT 4-1.  EXAMPLE PERMIT LANGUAGE FOR IDENTIFYING CSO OUTFALLS
                                IN A PHASE n PERMIT
  The permittee is authorized to discharge from the outfalls listed below in accordance with the
  requirements of [insert appropriate CSO section references] and other pertinent provisions of
  this permit.
     Overflow Number Overflow Outfall Location
     [insert number]   [insert latitude/longitude
                     (street address optional)]
Receiving Water Body
[insert receiving water body]
4.4    NINE MINIMUM CONTROLS
   The permit writer should determine whether the actions taken by the permittee to implement
the NMC during the Phase I permit are adequate.  This can be accomplished by reviewing the
information provided by the permittee during the Phase I permit term (i.e., NMC documentation
and the LTCP). Evaluation criteria are discussed in Section 4.4.1. The Phase n permit should
require continued implementation of the NMC.  When preparing the Phase n permit, therefore,
the permit writer should develop  site-specific  permit  language  requiring  the continued
implementation of the NMC and its associated documentation.  Section  4.4.2 provides site-
specific permit language.

4.4.1   Review of Permittee's Implementation of the Nine Minimum Controls
   As discussed in Section 3.10, the permit  writer,  in conjunction with other  appropriate
personnel, should have reviewed the NMC documentation for completeness and compliance with
Phase I permit requirements.  The documentation serves as the basis for the development of
technology-based requirements in the Phase II permit, on a BPJ basis  reflecting site-specific
considerations.
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  1         The permit writer should evaluate whether the actions already taken or being taken by the
  2      permittee are adequate to meet the NMC requirements.  This section provides general criteria
  3      for the permit writer to use to evaluate the adequacy of the permittee's NMC.  Because of the
  4      site-specific nature of the control measures, these criteria are not all inclusive but provide a basis
  5      for the evaluation that should be conducted by the permit writer. It should be noted that a single
  6      control measure can be used to comply with more than one of the NMC. For additional detail
  7      on the NMC control measures, see Combined Sewer Overflows—Guidance for Nine Minimum
  8      Control Measures (EPA,  1994).
  9
10         As discussed, upon receipt  of  the NMC  documentation, the permit writer must first
11      determine whether the documentation complies with the requirements set  forth in the permit.
12      After initial review of the documentation, if a permit writer determines that certain components
13      or subcomponents are incomplete or not properly addressed by the permittee, then the permit
14      writer should follow up with the permittee in one of two ways. If the permit writer believes that
15      missing or incomplete components are relatively significant and that the permittee has not acted
16      in good faith to submit the  documentation, then the permit writer may initiate an enforcement
17      action for noncompliance with  a  Phase I permit condition.  Any possible enforcement actions
18      should be coordinated with the appropriate enforcement personnel.  Alternatively,  if only minor
19      components are unclear or incomplete, the permit writer may simply want to request the missing
20      or incomplete data from the permittee in  accordance with the policies and procedures of the
21      NPDES permitting authority (e.g., informal telephone call request  or formal request letter).
22
23         Once the complete NMC documentation has been received, the permit writer should review
24      it using the criteria provided in the  following paragraphs.   These evaluation  criteria are also
25      provided in  checklist form in Appendix C.
26
27      Proper Operation and Regular  Maintenance Programs for the CSS and CSO Outfalls
28        When evaluating the permittee's O&M program, the permit writer should consider whether
29      the program:
30
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    •  Describes the system, identifying and addressing CSOs by including an inventory of all
       CSO structures, equipment, and treatment facilities.  Provides procedures for keeping
       this inventory current.

    •  Will be effective in reducing the number, frequency, and pollutant loading due to CSOs.

    •  Provides operating procedures and specifications for all equipment, structures,  facilities,
       CSO outfalls, and off-line storage structures.   Includes the hydraulic capacities of the
       collection and treatment systems, the storage capacities  of the collection and  treatment
       systems,  and off-line storage capacity.  Operating procedures should reflect the best use
       of the system's flow and routing controls to minimize CSOs.  Procedures should address
       the  identification and correction of CSS and CSO problems.

    •  Includes  routine inspection, maintenance,  and repair schedules for all CSO outfalls,
       interceptors, pumping stations,  and  equipment.  Schedules and inspection frequencies
       should be appropriate for the system.

    •  Involves  maintenance procedures, including routine inspections, schedules for collection
       system preventative maintenance, schedules for  cleaning and flushing of system and
       equipment, and response procedures for repairs.

    •  Requires logs or other documentation of completed activities.  Logs should also include
       documentation of  sewerage blockages.

    •  Addresses the location of overflows where O&M is hindered (i.e., devices are under
       major thoroughfares, railroad yards, or other difficult to reach or safety hazard areas).

    •  Allocates resources  for O&M program implementation,  including staffing level and
       funding, equipment, and training.
   The permit writer should note that in addition to the O&M program submitted as part of the

NMC documentation, the permittee will be submitting an operational plan as part of the LTCP.

(The operational plan will revise the O&M program to  include the permittee's selected CSO

controls.) Both of these submissions can be reviewed using the previously-listed factors. These

two submissions will be used to develop the Phase n permit requirement for an O&M program.


Maximum Use of the Collection System for Storage

   In evaluating the permittee's control measure, the permit writer should consider whether the

permittee has:
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  1         •  Identified portions  of the  CSS  usable for storage  and determined the CSS storage
  2            capacity, including configuration, size, and pump station capacity
  3
  4         •  Identified appropriate minor modifications to increase  storage (e.g., raised existing weirs)
  5
  6         •  Identified potential off-line storage at existing facilities
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  8         •  Implemented procedures for maximizing CSS  storage capacity.

  9

 10         The  permit writer should note that this control  measure may increase the possibility of

 11      flooding (e.g., basement) and that the potential for a permittee to increase collection system

 12      storage varies. Increased sedimentation in the collection system, more frequent cleaning, odor

 13      potential, and other factors should be considered in evaluating the potential for collection system

 14      storage.

 15

 16      Review and Modification of Pretreatment Programs

 17         Reviewing and modifying pretreatment programs applies primarily to permittees with

 18      approved pretreatment programs.   If the permittee does not have an approved pretreatment

 19      program, however, it should attempt to minimize CSO impacts from any nondomestic discharges

20      to the collection system.  In evaluating the permittee's control measure, the permit writer should

21      consider whether the permittee has:

22

23         •  Determined if the CSS receives nondomestic wastewater discharges.
24
25         •  Prepared an inventory  of nondomestic users who may discharge to  the same receiving
26            water body  as the CSOs.   Evaluated the discharge constituents and suspected impacts
27            from such users.
28
29         •  Evaluated the potential for regulating  either the volume  or pollutant  loadings from
30            nondomestic users to CSOs during wet weather flow  conditions.  The evaluation should
31            include a discussion of whether the modifications are feasible or of practical value for
32            CSO control.  For example, whether the permittee has considered requiring industrial
33            users  with  appropriate  storage  capacity  to temporarily  hold  wastewater during
34            precipitation events or when notified by the permittee, or has considered prohibiting new
35            users from discharging  stonnwater or uncontaminated water, such as non-contact cooling
36            water,  to the collection system.
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       Modified the pretreatment program  or, for permittees without approved pretreatment
       programs, taken actions to control nondomestic users.
Maximization of Flow to POTW Treatment Plant
   In evaluating the permittee's control measure, the permit writer should consider whether the

permittee has:
       Identified actions that could be taken to increase flows to the POTW treatment plant
       during wet weather flow conditions without significantly affecting treatment performance
       or contributing to performance problems

       Conducted plant tests to determine the plant capability to treat higher flows during wet
       weather flow conditions or determined  the maximum flow that can be treated,  using
       available historical data

       Developed, implemented, and documented implementation of a flow maximization plan
       during wet weather flow conditions.
Prohibition of CSOs During Dry Weather Flow Conditions
   In evaluating the permittee's control measure, the permit writer should consider whether the
permittee has:
      Developed adequate procedures to identify and document where and when dry weather
      overflows occur

      Developed and instituted procedures to eliminate dry weather overflows.
Control of Solid and Floatable Materials
   In evaluating the permittee's control measure, the permit writer should consider whether the
permittee has:
      Evaluated the following technologies for the removal of solids and floatables:  screening
      materials using baffles, screens, and netting; skimming from water body surface with
      booms at outfalls in confined areas; and source control, which may be addressed under
      the pollution prevention program for CSO outfalls (see Pollution Prevention Program
      below)
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       Identified and addressed problems that may be created by the installation of the control
       technology

       Implemented the appropriate control technology, considered and provided justification
       that the technology is appropriate for the site conditions, and is conducting associated
       inspections and regular maintenance.
Pollution Prevention Program
    In evaluating the permittee's control measure, the permit writer should consider whether the

permittee has:


    •  Evaluated both government agency (e.g., street cleaning, banning, or substitution of
       products, such as plastic food containers;  controlled use of pesticides, fertilizers, and
       other hazardous substances at public facilities) and public (e.g., used oil recycling,
       household hazardous waste collection) source control measures

    •  Addressed pollutants found in CSOs during the evaluation of the control measures

    •  Included a wide reaching public education program

    •  Evaluated mechanisms to encourage water conservation (e.g., public outreach, structuring
       of water/sewer service charges, local ordinance provisions)

    •  Allocated adequate resources to conduct pollution prevention program activities

    •  Implemented and maintained detailed records of pollution prevention activities

    •  Promoted the use of industrial/construction BMPs for stormwater.


Public Notification

    In evaluating the permittee's control measure, the permit writer should  consider whether the
permittee has:
   •   Evaluated options for public notification to ensure that the public receives adequate
       notification of CSO  occurrences and CSO impacts

   •   Implemented procedures that safeguard the public health through public notification of
       the presence of contaminants at critical levels in the receiving water bodies due to CSOs
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    •   Implemented procedures that notify persons reasonably expected to be affected by the
       CSO and reach the affected public
    •   Documented CSO occurrences and  associated notifications
    •   Installed identification signs at each CSO outfall.
Monitoring to Effectively Characterize CSO Impacts and Efficacy of CSO Controls
   The permittee is likely to have conducted monitoring required for this minimum control in
conjunction with CSS characterization associated with the LTCP development. Thus, the permit
writer should review the permittee's  monitoring efforts as a whole and assemble all applicable
monitoring data prior to the evaluation.  In  evaluating the permittee's monitoring data, the
permit writer should consider whether the  permittee has:

   *   Characterized the CSS to identify all CSO locations and receiving water bodies
   •   Collected data on the total number of overflow events and the frequency,  duration,
       volume, and pollutant loadings of CSOs
   *   Collected water quality data  and information on  water  quality  impacts  (e.g., beach
       closings, floatables, wash-up episodes, fish kills)
   •   Conducted monitoring to determine baseline data prior to  implementation of the NMC
   •   Conducted monitoring to determine baseline conditions subsequent to implementation of
       the NMC,  which may be used in LTCP development.

4.4,2   Permit Conditions
   Once  the  permit  writer  has  evaluated the permittee's  NMC  implementation  and
documentation efforts,  he/she  should  develop Phase n permit language that  requires  the
continued  implementation of the  NMC.   The permit  language  should  be tailored  to  the
permittee's specific circumstances and should incorporate both site-specific implementation and
recordkeeping requirements.  The permit writer may need to coordinate the development of this
permit language with the LTCP implementation language because it is possible that some of the
NMC control measures will be incorporated into the LTCP as selected CSO controls.
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  1         The permit writer  should establish  technology-based requirements in the Phase n permit
  2      based on  the permittee's documentation of the NMC and any alterations made in the LTCP.
  3      Example permit language is provided in Exhibit 4-2 for each NMC. A portion of this language
  4      is applicable to all permittees implementing the particular minimum CSO control.  Additional
  5      site-specific language,  which is tailored to the specific control measures implemented by the
  6      permittee, is given in italics.  Although  the site-specific language is  not applicable  to all
  7      permittees,  it is provided as an example  of the  type  of language and detail  appropriate for
  8      requiring  the NMC in the Phase n permit.  The permit writer may be able to select language
  9      directly from the permittee's NMC documentation or LTCP and incorporate it into the permit.
10
11         The permit writer should note that  no  site-specific permit language  was provided for the
12      monitoring  to effectively characterize  CSO impacts  and efficacy  of CSO controls.   This
13      monitoring must be integrated with the monitoring requirement to be placed  in the Phase H
14      permit associated with implementation of the LTCP.  For developing permit language for these
15      monitoring requirements, see Section 4.7.
16
17      Documentation for Fact Sheet/Statement of Basis
18         As required in 40  CFR Section 124.8, a fact sheet (or a statement of basis for  minor
19      discharges) must be prepared for every  NPDES permit. The purpose of the fact sheet is to set
20      forth the principal technical facts and the significant factual, legal, methodological, and policy
21      questions  considered  in  preparing  an  NPDES permit.  Although  40 CFR  Section  124.8
22      establishes the minimum requirements for a fact sheet, each permit  writer will probably prepare
23      a fact sheet in accordance with the format used by the permitting authority.
24
25         For Phase II permits that are requiring  the implementation of the NMC, the permit writer
26      must discuss in the fact sheet the basis  for the NMC requirements.  The permit writer should
27      use  the permittee's NMC documentation  to record in the  fact sheet the justification for
28      implementation of the specific minimum controls chosen by the permittee. Further, the permit
29      writer must  discuss the fact that the NMC  are being used, on a case-by-case basis, to comply
30      with the technology-based requirements  of the CWA in lieu of numeric effluent limitations (see


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                       EXHIBIT 4-2. EXAMPLE PERMIT LANGUAGE FOR
             CONTINUED IMPLEMENTATION OF THE NINE MINIMUM CONTROLS
  I.   Effluent Limits

  A.  Technology-based requirements for CSOs.  The permittee shall comply with the following technology-
      based effluent limits in the form of narrative controls:

      1.   Conduct proper operations and regular maintenance programs.  The permittee shall implement the
          Operation and Maintenance Plan for the combined sewer system that will include the elements listed
          below.  The permittee also shall update the plan to incorporate any changes to the system and shall
          operate and maintain the system according to the plan.  The permittee shall keep records to
          document the implementation of the plan.

          Site-Specific Language:

          Designation of a Manager for Combined Sewer  Overflows.  The permittee shall designate a person
          to be responsible for the wastewater collection system and serve as the contact person regarding
          combined sewer overflows.  The permittee shall notify the permitting authority within [specify
          number of days] of designation of a new contact person.

          Inspection and Maintenance of CSS.  The permittee shall inspect and maintain all CSO structures,
          regulators, pumping stations, and tidegates to ensure that they are in good working condition and
          adjusted to minimize  CSOs and prevent tidal inflow. The permittee shall inspect, or cause to be
          inspected, each CSO outfall at least [specify frequency for inspection].   The inspection shall
          include, but is not limited to, entering the regulator structure if accessible,  determining the extent of
          debris and grit build-up, and removing any debris that may constrict flow,  cause blockage, and
          result in a dry weather overflow.  The permittee shall record in a  maintenance log book the results
          of the inspections.  For CSO outfalls that are inaccessible, the permittee may perform a  visual check
          of the overflow pipe to determine whether or not the CSO is occurring during dry weather flow
          conditions.

          Provision for Trained Staff.  The permittee shall provide an adequate number of full-time equivalents
          to carry out the operation, maintenance, repair, and testing functions required to ensure compliance
          with the terms and conditions of this permit. Each member of the staff shall receive appropriate
          training.

          Prioritization Maintenance Needs.  The permittee shall develop a prioritized list of maintenance
          needs and a proposed implementation schedule.  The permittee shall submit this list to the permitting
          authority within [insert number] months of the effective date of the permit,

         Allocation of Funds for Operation and Maintenance. The permittee shall allocate adequate funds
         specifically for operation and maintenance activities. The permittee shall submit a certification of
         assurance from the affected local government entities that the necessary funds, equipment, and
         personnel have been or will be committed to carry out the  O&M plan.
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                            EXHIBIT 4-2. EXAMPLE PERMIT LANGUAGE FOR
              CONTINUED IMPLEMENTATION OF THE NINE MINIMUM CONTROLS  (continued)
      2.   Maximize use of the collection system for storage.  The permittee shall maximize the in-line storage
          capacity.  The permittee shall keep records to document implementation.

          Site-specific language:

          The permittee shall 1) maintain all dams at diversion structures at their current heights (as of the
          date of permit issuance) or greater, 2) minimize discharges from  the CSO outfall locations
          designated as [insert appropriate designation] until the entire available capacity of the [named]
          Combined Sewer Retention Basin is used to store the overflow for later treatment at the plant, and 3)
          keep records of the flow entering and leaving the [named] Combined Sewer Retention Basin,


      3.   Review and  modify pretreatment program. The permittee shall continue to implement selected CSO
          controls to minimize the impact of nondomestic discharges from CSOs.  The permittee shall re-
          evaluate [specify frequency] whether additional modifications to its pretreatment program are
          feasible or of practical value.  The permittee  shall keep records to document this evaluation and
          implementation of the selected CSO controls  to minimize nondomestic discharges from CSOs.

          Site-specific language:

          The permittee shall prohibit the addition of new or increased volumes of industrial process or high-
         strength wastewaters into the sewer system under circumstances where they could be discharged
         through a CSO outfall.

          [Alternative language for permittee without an approved Pretreatment  Program.]

          Actions to minimize impact  of nondomestic discharges from CSOs. The permittee shall continue to
          implement selected CSO controls to minimize the impact of nondomestic discharges from CSOs.


      4.   Maximize flow to POTW treatment plant.  The permittee shall operate the POTW treatment plant at
         maximum treatable flow of at least [insert appropriate number] MOD during wet weather flow
         conditions/events and deliver all  flows to the  treatment plant within the constraints of the capacity of
         the treatment plant.  The permittee shall keep records to document these actions.


      5.  Prohibit combined sewer overflows during drv weather.  Dry weather overflows from CSO outfalls
         are prohibited. All dry weather overflows must be reported to the permitting authority within
          [insert appropriate  number of days] of when  the permittee becomes aware of a dry weather
         overflow.  When the permittee detects a dry weather overflow, the permittee shall begin corrective
         action immediately.  The permittee shall inspect the dry weather overflow each subsequent day until
         the overflow has been eliminated. The  permittee shall record in the inspection log book dry weather
         overflows, as well as the cause, corrective measures taken, and the dates of beginning and cessation
         of overflow.
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                            EXHIBIT 4-2. EXAMPLE PERMIT LANGUAGE FOR
              CONTINUED IMPLEMENTATION OF THE NINE MINIMUM CONTROLS  (continued)
      6.   Control solid and floatable materials in CSOs.  The permittee shall implement measures to control
          solid and floatable materials in its CSOs.

          Site-specific language:

          These control measures shall include:

              (i)  Ensure that all overflows from the diversion structures are baffled or that other means are
                 used to reduce the volume  of floatables.
              (ii) Inspect and maintain the sewer system so that solids or floatable material greater than
                 [insert size] are not present in CSOs.
              (Hi)    Remove solid or floatable materials captured by a [insert appropriate numberj-inch
                     screen  and dispose of this material in an acceptable manner prior to discharge to the
                     receiving water.  Overflows containing solid or floatable materials that may be captured
                     by a [insert appropriate numberj-inch screen are prohibited.


      7.   Develop and implement pollution prevention program.  The permittee shall implement a pollution
          prevention program  focused on reducing the impact of CSOs on receiving waters. The permittee
          shall keep records to document pollution prevention implementation activities.

          Site-specific language:

          This program shall include:

              (i)      Conducting street s)veeping and catch basin modification or cleaning at a frequency that
                     will prevent large accumulations of pollutants and debris, but no less than [specify  a
                     minimum frequency]
              (ii)     Conducting a public education program that informs the public of the permittee's local
                     laws that prohibit littering and the use of phosphate-containing detergents and pesticides
              (Hi)    Instituting an oil recycling program.
      8.  Notify the public of CSOs. The permittee shall continue to implement a public notification plan to
         inform citizens of when and where CSOs occur.  The process must include:

         a.  A mechanism to alert persons using all receiving water bodies affected by CSOs

         b.  A system to determine the nature and duration of conditions that are potentially harmful to users
             of these receiving water bodies due to CSOs.

         The permittee shall keep records documenting public notification.
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                         EXHIBIT 4-2. EXAMPLE PERMIT LANGUAGE FOR
             CONTINUED IMPLEMENTATION OF THE NINE MINIMUM CONTROLS (continued)
        Site-specific language:
        Within 3 months of the effective date of this permit, the permittee shall install and maintain
        identification signs at all CSO outfalls owned and operated by the permittee.  The permittee must
        place the signs at or near the CSO outfalls and ensure that the signs are easily readable by the
        public.  The signs shall be a minimum of 12 by 18 inches in size, shall be metal, and shall contain
        the following information:  1) permittee name; 2) wet weather sewage discharge; 3) outfall
        (discharge serial number); and 4) telephone  number and contact.

     9.  Monitor to effectively characterize CSO impacts and the efficacy of CSO controls.  The permittee
        shall regularly monitor CSO outfalls to effectively characterize CSO impacts and efficacy of CSO
        controls.
        Site-specific language:
        [For example language, see page 4-31J
Section 3.6.1). For further guidance related to preparing a fact sheet or statement of basis, the
permit writer should refer to Training Manual for NPDES Permit Writers (EPA, 1993).

4.5    LONG-TERM CONTROL PLAN
   Upon receipt of interim deliverables (see Section 3.5), the permit writer will be responsible
for their review and for working  closely with the permittee to ensure that any inadequacies,
problems, or issues are addressed in a  timely fashion prior to  submission of the completed
LTCP and the development and issuance of the Phase II permit.

   In preparing for the development and issuance of a Phase H permit, the permit writer must
review the LTCP submitted by the  permittee.  Subsequent to the review  of the LTCP, the permit
writer must  require implementation of the selected CSO controls identified in  the LTCP.  The
primary responsibility of the permit  writer in developing Phase U permits is to ensure that the
CSO controls proposed by the permittee comply with the requirements of the CWA, achieve
State WQS,  and are consistent with the intent of the CSO Control Policy.  The requirement to
implement  these  controls  must be appropriately reflected as  enforceable  NPDES  permit
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conditions. This section provides guidance for the permit writer in reviewing the LTCP and
developing permit conditions to implement the LTCP.


4.5.1  Coordination of the Review  and Evaluation
    The permit writer will need to coordinate the input from a variety of agencies to ensure that
CSOs comply with the CWA, including attainment of WQS. Therefore, the permit writer should
form  and coordinate a review team that will be responsible for reviewing the LTCP.  An
appropriate review  team should include the following types of personnel:
    •   WQS personnel to assist in evaluating proposed CSO controls and to review and revise
       State WQS, as appropriate. WQS personnel can also assist in evaluating any ambient or
       special  monitoring conditions (e.g., toxicity  testing) that may be required during the
       Phase n permit to monitor the effectiveness of the selected CSO controls.

    •   Enforcement personnel to assist in ensuring  that  permit  language  is  enforceable.
       Enforcement personnel can also provide input on the use of enforcement mechanisms
       (e.g., administrative orders) to  require implementation of the selected CSO controls.
       This will be particularly important  if extensive time is required by the permittee to
       comply with Phase n permit requirements.

    •   Field personnel (e.g., EPA's Environmental Services Division personnel) to help review
       monitoring plans and the development of CSO monitoring requirements

    •   Storm water and nonpoint source pollution personnel for watershed issues.
4.5.2  Review of Long-Term Control Plan
   As discussed in Section 3.5.2, the permittee is likely to be submitting parts of the LTCP as
interim deliverables during the Phase I permit term.  The permit writer and other members of

the review team should be reviewing these deliverables, as well as the completed LTCP detailing
the permittee's selected CSO controls, as soon as they are submitted.


   Upon submission and receipt of the LTCP, the permit writer should first determine whether
the LTCP complies with the requirements set forth in the Phase I permit.  After initial  review
of the LTCP, if a permit  writer determines that certain components or  subcomponents are
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  1      incomplete or not properly addressed by the permittee, the permit writer should follow up with
  2      the permittee.  For information on followup procedures, see Section 4.4.1.
  3
  4         The permit writer, with support from  the review team, should review the LTCP to ensure
  5      consistency  with the  CSO Control Policy and to ensure  that the selected  CSO controls are
  6      reasonable and will result in compliance with CWA requirements.  Of the various CSO control
  7      alternatives  considered by the permittee during the Phase I permit term,  one or a combination
  8      of alternatives will be selected for implementation by the permittee.  The LTCP should discuss
  9      all of the alternatives and, more importantly, why the selected CSO controls were chosen.
10      There should also be a discussion related to the selected CSO controls, including maximization
11      of treatment at the POTW treatment plant; the operational plan;  integration of the NMC;
12      monitoring;  costs of the selected CSO controls and financing; and the implementation schedule,
13      possibly  including identification of milestones where re-evaluation and  modifications would
14      occur.  All  other parts of the  LTCP,  including the CSS  and  water quality  characterization
15      monitoring and modeling used during the development process, the other alternatives and costs,
16      and public participation, ultimately become "historical" material that will not  be addressed in
17      the Phase n permit, because they  are not part of the selected CSO controls.   However,  this
18      information  is critical for appropriate review of the LTCP.
19
20         The remainder of this section presents questions the permit writer should consider while
21      reviewing the LTCP.  These evaluation  criteria are also provided in a checklist in Appendix D.
22      These review  questions are based on the requirements of the CSO Control  Policy and the
23      guidance provided in  the Combined Sewer Overflows—Guidance for Long-Term Control Plan
24      (EPA, 1994).  Although the permit writer may use these questions as the basis for review, the
25      permit writer may need to  supplement them to reflect the site-specific Phase I permit conditions
26      established for a particular permittee. For example,  if a permit specifically required monitoring
27      and evaluation of certain  pollutants of concern, then a permit writer should ensure that the
28      permittee has addressed these pollutants in its monitoring plan.
29
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   In reviewing the LTCP using the following questions, the permit writer should remember
that the level of detail in the LTCP can vary significantly depending on the permittee and its
CSS.   The overall intent of the review is to ensure that the LTCP is a coherent, organized
document and that the permit writer can follow a logical step-by-step analysis justifies how the
selected CSO controls were chosen.

Public Participation
   When the permittee submits its proposed  public participation plan as an interim deliverable
of the LTCP development, the permit writer  should review it with other appropriate staff from
the review  team. When  evaluating the public participation  element of the LTCP, the permit
writer  should consider  the following evaluation questions to ensure the proposed plan,  once
implemented, results in an effective public participation program:
       Does the public participation process seek to actively involve rate payers, industrial users
       of the CSS, persons near the impacted waters, and persons who use the impacted waters?
       Does the public participation  plan  document how the  public was  notified of public
       participation events?
       Does the public participation plan include a record of the public participation events,
       including the number of people attending and a record or summary of comments?
       Does the  public participation plan contain a summary of comments and the changes or
       decisions  made in response to public comments?
CSS Characterization, Monitoring, and Modeling
   When the permittee submits a proposed  monitoring plan as an interim deliverable of the
LTCP development, the permit writer should review it with other appropriate staff from the
review team.  When evaluating this element of the LTCP, the permit writer should consider the
following questions to ensure the proposed plan,  once  implemented,  will be  an effective
monitoring program that provides the necessary data:

   •  Is there a general  description of  the CSS  that includes the geographical  area and
      population served?
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  1         •  Is there a map of the CSS depicting the location of all CSO outfalls and receiving water
  2            bodies?
  3
  4         •  Is there information on the volume, flow rate, and frequency of CSOs and the pollutants
  5            discharged?
  6
  7         •  Is the description  of how the CSS responds to rainfall events sufficient enough to
  8            determine which rainfall events trigger CSOs?
  9
 10         •  Have sensitive areas and all outfalls discharging to these areas been identified?
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 12         *  Is there information on the CSO pollutant loadings and their impact on receiving waters?
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 14         •  Is there information on designated water uses and whether designated uses are being met?
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 16         •  Does the CSS and CSO characterization provide information on the known effects of the
 17            CSOs on water quality during precipitation events, as well as provide the level of detail
 18            needed to model or project both the operation of the system and the impacts of various
 19            overflow scenarios on the receiving waters?
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 21         •  Is monitoring  sufficient to document baseline conditions to allow the permittee to
 22            demonstrate the long-term benefits of CSO  controls?
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24         •  If modeling was conducted, is the model identified and described,  and are the results
25            provided?

26
27         Appendix B contains additional information on  reviewing monitoring plans.

28

29      CSO Alternatives
30         When evaluating this element of the LTCP,  the permit writer should consider the following

31      questions:
32

 33         •  Did the permittee develop a comprehensive list of CSO control alternatives? Did this list
34            include alternatives from each of the four general  categories—source controls, collection
 35            system controls, storage,  and treatment technologies (described in Combined  Sewer
36            Overflows—Guidance for Long-Term Control Plan [EPA, 1994])?
37
 38         •  Are the CSO control alternatives that were  considered described?
39
40         •  Do CSO control  alternatives achieve WQS?
41
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   •   Did the plan describe the approach used to screen the list of CSO control alternatives,
       including the screening criteria? Did the screening criteria include performance factors,
       implementation and operation factors, and environmental factors (described in Combined
       Sewer Overflows—Guidance for Long-Term Control Plan [EPA,  1994])?

   •   Did the plan describe the process by which the CSO control alternatives were developed?

   •   Is  cost/performance information  (including curves) for  each  of the  CSO control
       alternatives provided?  Did the cost/performance analyses evaluate the alternatives for
       the capability to achieve zero overflow events per year,  and averages of 1 to 3, 4 to 7,
       and 8 to 12 overflow events per year?
Selected CSO Controls

   When evaluating this element of the LTCP, the permit writer should consider the following

questions:


   •   Which CSO control approach is selected?

   •   Is the selected CSO control approach a presumption or demonstration approach?

   •   Does the plan identify  the CSO controls that will  be implemented and  reasons for
       rejecting others?

   •   Have the NMC been integrated into  the permittee's description  of its selected CSO
       controls?

   •   Will the selected CSO controls eliminate all CSO points to sensitive areas? If not, do
       the data  support  the permittee's conclusion  that elimination is  not  physically or
       economically feasible?

   •   If CSO outfalls to sensitive areas will remain:

          -  Will these CSOs receive treatment?
          -  Will the CSO controls be sufficient to protect WQS?

   •   Will the CSO controls provide treatment or removal of floatables and settleable solids
       equivalent to that achieved by primary clarification?  Is the mechanism  for solids and
       floatables disposal described?
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  1         •  Will the disinfection of effluent be necessary?  Is disinfection proposed as part of the
  2            CSO controls? If not, does the information support the conclusion that disinfection is not
  3            necessary?  If disinfection is proposed, will  removal of harmful disinfection chemical
  4            residuals be necessary?

  5         •  Based  on the cost/performance information,  do the selected CSO controls provide the
  6            maximum pollution reduction benefits reasonably attainable?
  7
  8         •  Based  on the information, will the selected CSO controls protect WQS?  If WQS cannot
  9            be met because of sources other than CSOs, has the permittee provided information on
 10            the other sources and natural background  conditions?
 11
 12         •  Are the selected CSO controls designed to allow cost-effective expansion or cost-effective
 13            retrofitting if additional controls are determined necessary  to meet WQS?
 14

 15      Implementation  Schedule
 16         In reviewing the implementation schedule, the permit writer should use both the data and

 17      information supporting the prioritization of the CSO projects on the basis of their environmental

 18      impacts, as well as the  analysis of financial capability.   The permit writer  should refer to the

 19      Combined  Sewer Overflow—Long-Term  Control Plan  (EPA, 1994)  and Combined Sewer

20      Overflow—Financial Capability Assessment (EPA, 1994) guidance documents for criteria to

21      evaluate the reasonableness of the implementation  plan, including any construction schedules and
22      financing plans.  He/she should refer to the following questions when reviewing this component:
23
24
25         •  Do  any phased construction  schedules include an analysis  of financial capability?  Did
26            the  permittee evaluate the following factors:
27
28            -   Median household income
29            -   Total annual wastewater and CSO control costs per household as a percent of median
30                household income
31            -   Overall net debt as a percent of full market property value
32            -   Property tax  revenues as a percent of  full market property value
33            -   Property tax  collection rate
34            -   Unemployment
35            -   Bond rating
36            -   Grant and loan availability
37            -   Previous and current residential, commercial, and industrial sewer user fees and rate
38                structures
39            -   Other viable  funding mechanisms and  sources of financing
40            -   Debt indicators (e.g., overall net debt  as a percent of full market property value)?
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  1         •  Does the schedule include milestones for all major implementation activities,  including
  2            environmental reviews, siting of facilities, site acquisition, Army Corps of Engineers
  3            permitting, etc.?
  4
  5         The permit writer should review the financing plan to see if it provides the funds necessary
  6      to construct CSO controls and assess whether water quality considerations demand  a shorter
  7      timeframe than the proposed implementation schedule.  If so,  the permit writer may consider
  8      requiring specific CSO controls to be implemented on a shorter but still reasonable timeframe.
  9
10      Operational Plan
11         In  evaluating this  element of the LTCP, the permit writer  should  consider whether the
12      permittee's O&M program  addresses the selected CSO controls and other evaluation criteria
13      proposed in Section 4.4.1.
14
15      Post-Construction Compliance Monitoring
16         The permit writer  should review the monitoring  plan with appropriate staff (i.e.,  staff
17      knowledgeable in monitoring program design and implementation) from the review team. When
18      evaluating this element of the LTCP, the permit writer should consider the following questions:
19
20         •  Does the monitoring program include monitoring of representative CSOs?
21
22         •  Does the monitoring program  include ambient receiving water body monitoring at
23            representative CSOs, as well as monitoring prior to CSO impacts?
24
25         •  Does the monitoring program include any biological parameters (e.g., fish, zooplankton)?
26
27         •  Does the monitoring program address all applicable WQS?
28
29         Appendix B contains additional information on the review of a monitoring plan.
30
31      4.5.3  Implementation of the Long-Tenn Control Plan
32         As described in the  CSO Control Policy, Phase  n permits should  contain "narrative
33      requirements that ensure the selected CSO controls are implemented, operated, and maintained
34      as described in the long-term CSO control plan." Because the selection  of the CSO controls will

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be  made on  a site-specific  basis, the conditions  in  the  Phase n permit requiring  the
implementation of the selected CSO controls should be tailored to the site-specific conditions.

    The permit writer should not simply develop a generic permit condition that requires the
permittee to implement the LTCP as developed, incorporating the LTCP into the NPDES permit
by reference.   It is recommended that the permit writer develop specific permit conditions that
directly address the selected CSO controls.  Permit conditions should be developed that require
implementation of the selected CSO controls, the proposed O&M program requirements, and
the proposed post-construction compliance monitoring program. A brief discussion for each of
these portions of the LTCP is provided below.

Selected CSO Controls
    To ensure that a permittee will implement its selected CSO controls, the permit writer must
develop permit requirements that specifically require the implementation of the  selected CSO
controls. As discussed above, due to the differences among CSSs, it is expected that selected
CSO controls  identified in  LTCPs will vary from  system to system.  In many  cases,  the
permittee's selected CSO controls will require major construction and implementation activities;
these activities may require many years to complete over several NPDES 5-year permit cycles.
The CSO Control Policy recommends that the permittee include in the LTCP the information
and data necessary to develop the fixed-date schedules for funding and implementing the CSO
control program. In the LTCP, the permittee should prioritize the individual projects within the
overall control  program on the  basis of environmental  impacts and available funding.  See
Section 3.5.1  for additional discussions on the permittee's  development of implementation
schedules.

   When the implementation schedules for the selected CSO controls are established, the permit
writer should determine the appropriate mechanism for imposing the schedule on the permittee.
The permit writer will require in  the Phase n permit  that the permittee,  immediately upon
issuance of the permit, comply with applicable WQS, as well as BAT/BCT requirements.  In
nearly  all cases, the permittee will  be unable to do  so.  Therefore, the permit writer should
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include a fixed-date implementation schedule either in the Phase n permit or in an enforcement
mechanism issued with the Phase II permit. Where lawful under the CWA and allowed by State
WQS, the permit writer may use the Phase n permit as the enforceable mechanism.

    A permit writer in a State that does not allow fixed-date implementation schedules in NPDES
permits and an EPA permit writer must use an appropriate enforcement mechanism issued in
conjunction with the Phase H  permit.   Appropriate enforcement  mechanisms may include
administrative orders or judicial orders.  The permit writer should discuss with the appropriate
enforcement authority the choice of the mechanism to use in each individual situation.

    Exhibit 4-3 provides example language requiring  compliance with a LTCP implementation
schedule for the selected CSO controls. The example provided in this exhibit assumes that the
permittee has successfully implemented the NMC, and the schedule is to implement the selected
CSO controls identified in the LTCP.  In this permit  requirement, the permit writer should list
specific activities for the permittee's selected controls. For example, if one of the selected CSO
controls is construction of a retention basin,  the permit writer should include specific language
for the various activities necessary to complete the construction, as shown in the italicized site-
specific language in Exhibit 4-3. These activities and the corresponding completion dates should
be taken directly from the LTCP whenever possible. In many instances, the permittee may have
a combination of selected CSO controls in its  LTCP, such as building additional retention basins,
separating portions of the CSS, and maximizing flow  receiving primary treatment at the POTW
treatment plant.  In these cases, the permit writer should  include activities with corresponding
completion dates for implementing each of the selected CSO controls.  It should be noted that
in addition to identifying compliance dates within the implementation schedule, the permit writer
should also require periodic reporting (i.e.,  progress reports) to demonstrate compliance with
the various compliance dates.   Section 4.8  provides additional guidance related to reporting
requirements for the Phase n permit.
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1 Operational Plan
2 As described in Section 4.4.2, permittees will be required to develop an O&M program

as
3 part of the NMC. Once the selected CSO controls have been chosen by the permittee as part
4 of its LTCP, the permittee should revise the O&M plan developed and implemented as part
of
5 the NMC to include the selected CSO controls. The permit requirements for the implementation
6 of the O&M program are contained in Section 4.4.2.
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EXHIBIT 4-3. EXAMPLE PERMIT LANGUAGE FOR
IMPLEMENTING SELECTED CSO CONTROLS
II. Long-Term Control Plan

The permittee shall implement and effectively operate and maintain the selected CSO controls
in the long-term control plan. The implementation schedule for this program shall be as
follows:

Activity Completion Date .

[insert name of activity] [insert date]

Site-specific language:

I. Retention basin

a. Complete design of [named] retention basin.
b. Submit construction drawings for [named] retention basin.
c. Initiate construction of [named] retention basin.
d. Complete construction of [named] retention basin.

2. Main street sewer separation

a. Complete design.
b. Solicit bids.
c. Award contracts.


NOTE: A compliance schedule exceeding the term of the permit may only be included in the
permit if allowed by State WQS.
































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Post-Construction Compliance Monitoring
   Requiring implementation of the post-construction compliance monitoring program proposed
by the permittee as part of its LTCP is important for determining the overall effectiveness of the
selected CSO control(s)  in achieving compliance with  CWA.  It may not be appropriate to
require the implementation of a post-construction  monitoring program until construction is well
underway or completed.  The permit writer should refer to Section 4.7  for further guidance
regarding Phase n permit monitoring requirements.

Documentation for Fact Sheet/Statement of Basis
   As discussed previously,  the permit writer must prepare a  fact sheet or statement of basis
that justifies any NPDES permit conditions established for a  permittee.   For Phase n CSO
permits  that  require the implementation of an  LTCP,  the  permit writer  should  use  the
information from the LTCP to record in the fact sheet or statement of basis the justification for
implementation of the specific CSO controls chosen by the permittee.

4.6   EFFLUENT LIMITATIONS
   Similar to the Phase I permit, 40  CFR Section 122.44  (NPDES requirements) requires that
both technology- and water quality-based effluent  limitations be included in the Phase n permit.
However, these two permit phases differ from each other with respect to effluent limitations in
the type of effluent limitation each permit phase requires.  Phase I allows for the establishment
of narrative effluent water quality limitations; Phase II allows  water quality limitations  in the
form  of numeric performance  standards  (i.e., number  of overflow  events per year) for the
selected CSO controls. When sufficient CSO-related information and data are available for the
permit writer to develop numeric water  quality-based effluent limitations, the permit writer
should do so. However,  this information  is  not likely to be available for inclusion in the Phase
II permit.

4.6.1  Technology-Based Requirements
   Phase II permits should require that CSO permittees continue to implement technology-based
controls.   These technology-based controls include the NMC  on a BPJ  basis, but may also
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  1      include components of the selected CSO controls from the LTCP. The permit writer should re-
  2      evaluate and incorporate appropriate NMC requirements in the Phase n permit, as discussed in
  3      Section 4.4.  The discussion of the technology-based requirements of CSOs with respect to the
  4      CWA and NPDES permitting  requirements that appears in Section 3.6.1  is also applicable to
  5      Phase n permits.
  6
  7      4.6.2  Water Quality-Based Requirements
  8         Based on the review of NMC documentation submitted by the permittee, a permit writer may
  9      also decide that implementation of certain components of the LTCP may  also be necessary to
10      achieve the BAT/BCT requirements of the CWA.  This situation would occur, for example, if
11      a permit writer determines that the NMC for one permittee are  not resulting in the same level
12      of pollutant reductions being achieved by the NMC implemented by another permittee. As a
13      result, the permit writer  should consider whether BAT/BCT levels would be better achieved
14      through the implementation of a combination of the NMC and LTCP components.
15
16         As described in Section IV.B.2 of the CSO Control Policy, Phase II permits should contain
17      "water quality-based effluent limits required under 40 CFR Sections 122.44(d)(l) and 122.44(k),
18      requiring compliance with, no later than the date allowed under the State's WQS, numeric
19      performance standards for the  selected  CSO controls,...."  The CSO Control Policy assumes
20      that adequate data will not be available at the beginning of the Phase  n permitting process for
21      the permit writer to fully and accurately assess the need for numeric water quality-based effluent
22      limits. Consequently, the  CSO Control  Policy depends on compliance with the  performance
23      standards of the selected CSO controls for water quality protection. The performance standards
24      to be applied to a permittee will depend on the CSO control approach selected by the permittee.
25      The CSO Control Policy specifies the performance  standards for the presumption  approach.
26      Conversely, to satisfy the demonstration approach, the permit writer must establish performance
27      standards for the selected CSO controls  that will contribute to  the attainment of WQS.  The
28      water quality-related considerations for each approach are discussed in greater detail below.
29
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   In addition to performance standards designed to meet WQS, the permit writer should include
narrative permit language requiring compliance with WQS. In certain circumstances, sufficient
data may exist (e.g., the permittee has substantially  completed construction of selected CSO
controls) for the permit writer to develop numeric water quality-based effluent limits.  In these
cases, the permit writer should refer to the Technical Support Document for Water Quality-based
Toxics Control (EPA, 1991) for guidance on determining the need for water quality-based
effluent limitations.

Presumption Approach
   Under the presumption approach, permittees  are  required to  meet numeric performance
standards (e.g., certain number of overflow events per year). These criteria were established
in the CSO Control Policy because "data and modeling of wet weather events often do not give
a clear  picture of the level of CSO controls necessary  to protect  WQS."  Therefore, it is
presumed that compliance with these numeric performance standards will be sufficient to meet
WQS.  The permit writer will  be  responsible, however, for  ensuring that this presumption is
reasonable  for the CSOs to be permitted.  To  determine  if the  presumption  approach is
reasonable, the permit writer must  review the  data generated  and  analysis conducted to
characterize, monitor, and model the CSS and review the consideration of sensitive areas by the
permittee.

   As stated in the CSO  Control Policy and discussed previously,  the permit writer must also
reflect the selected evaluation approach in  the form of performance standards in  the Phase n
permit to fulfill the water quality-based effluent limitation requirements of the CWA and NPDES
program  requirements.  Exhibit 4-4 provides example permit language for a  permittee that used
the presumption approach.

   The permit writer will be responsible for eventually reviewing the permittee's evaluation of
CSO controls and determining whether water quality will  be  adequately protected.  It is likely
that an adequate demonstration  and review for compliance with WQS will not be possible until
the permittee has implemented its selected CSO controls.  Therefore, a  complete evaluation by
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the permit writer, including considering the development of numeric water quality-based effluent

limitations, may not occur until the post-Phase n CSO permitting.
                      EXHIBIT 4-4.  EXAMPLE PERMIT LANGUAGE FOR
                PERFORMANCE STANDARDS FOR THE PRESUMPTION APPROACH
 I.   Effluent Limitations

 B.  Water quality-based requirements for CSOs

     The permittee shall not discharge any pollutant at a level that would cause or contribute to a
     violation of [insert name of State] water quality standards.

     The permittee shall comply with the following performance standards. These standards shall
     apply during [insert average design conditions under which controls are based upon].

     1.  [The permit writer should select the appropriate standard below.]

        The permittee shall discharge no more than an average of [insert appropriate number: 4,
        5, or 6] overflow events per year not receiving the equivalent of primary clarification.

                                            or

        The permittee shall capture for treatment, or storage and subsequent treatment, at least 85
        percent of the system-wide combined sewage volume collected in the combined sewage
        system during precipitation events under design conditions.  Captured combined sewage
        shall be directed either to the [insert name of treatment plant(s)] or to the CSO storage
        tanks located at [insert location of storage tanks].

                                            or

        The permittee shall reduce the mass of the following pollutants [insert pollutants] that
        have been identified as causing water quality standard violations for at least 85 percent of
        the system-wide combined  sewage volume collected in the combined  sewage system during
        precipitation events under design conditions.

     [Insert the following language only if the first or second alternative is chosen above.]

     Any combined  sewage captured shall receive a minimum of the following treatment:

        (i)  Primary clarification or equivalent.
        (ii) Disinfection.  Fecal coliform counts  shall be maintained below [insert applicable
            level].  [Insert appropriate dechlorination requirements if applicable based on
            State water quality standards.]
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  1      Demonstration Approach
  2         Under the demonstration approach, permittees are required to show that the selected CSO
  3      controls  will not cause or contribute to  the exceedance  of  WQS.  Permit writers will be
  4      responsible for ensuring that the permittee adequately proves that the selected CSO controls are
  5      adequate to meet WQS. The specific performance standards that should be included in a permit
  6      will depend on the selected CSO controls.  Example permit language has  not been provided
  7      because it will be site-specific and based on the permittee's demonstration.  However, the permit
  8      writer should attempt to draft permit language in terms of performance standards or other clear
  9      specific standards.   It should be noted that not all selected CSO controls  will lend themselves
10      to specific numeric performance standards  (e.g., extensive use of BMPs).  However, the permit
11      writer should still attempt to develop permit conditions that will hold the permittee accountable
12      for implementing CSO controls as planned (e.g., specifying frequency and/or constant evaluation
13      of BMPs).
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15      4.7    MONITORING
16         During Phase n, monitoring is necessary to 1) evaluate the water quality impacts from CSOs
17      on  receiving  waters and the effectiveness  of CSO controls and 2) determine compliance with
18      permit conditions and ultimately WQS. The first type of monitoring should be conducted during
19      the Phase n permit term and should be sufficient to evaluate water quality impacts of CSOs on
20      the receiving water bodies and to  evaluate the effectiveness of CSO controls (i.e., trends,
21      improvements, elimination of CSOs) during the construction/implementation period. The latter
22      type of monitoring should be conducted after construction  of  selected CSO controls has been
23      completed (i.e., post-construction compliance monitoring).
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25         The proposed post-construction compliance monitoring plan should be submitted as part of
26      the LTCP. The  requirements for conducting the post-construction monitoring program should
27      be included in either the last Phase II or the first post-Phase H permit (see Chapter 5).   This
28      program  will  include ambient receiving water body pollutant monitoring both at the CSO outfall
29      and prior to the CSO impact. The types of pollutants and  parameters to  be included in  either
30      of these monitoring programs will depend on the WQS in  the receiving  water body and may
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  1      include chemical (e.g., BOD, TSS, metals, oil and grease, herbicides, pesticides), and biological
  2      (e.g., fish, benthic invertebrates, zooplankton) parameters.
  3
  4         Monitoring condition permit language should be both clear and concise, while maintaining
  5      flexibility to account for site-specific factors.  The permit writer is strongly encouraged to
  6      develop permit conditions that incorporate specific elements of the submitted plan with specific
  7      rather than general requirements so the conditions are enforceable. The permit writer may copy
  8      specific portions of the proposed plans into the permit.   An example of site- specific permit
  9      language is shown in Exhibit 4-5.  This exhibit is merely an example of site-specific language
10      and is not applicable to all CSOs.
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15      language.
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17         If CSOs are causing substantial water quality impacts, the permit writer may want to require
18      special characterization studies, including the following:
19
20         •  Sediment studies
21         •  Whole effluent toxicity testing
22         •  Biological assessments.
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24         For additional  information on these types of testing,  the permit writer is referred to the
25      Combined Sewer Overflow—Modeling and Monitoring Guidance (EPA, 1994).
26
27      4.8  REPORTING
28         Four types of reporting requirements relating  to CSO controls should be included in the
29      Phase n permit:  1) re-evaluations associated with and reports/recordkeeping to document
30
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ana is not applicable to all Cfcus.

   Alternatively, the permit writer can require implementation of the monitoring plan submitted
by the permittee.  The permit writer is cautioned against the use of this approach  because
conditions that only refer to the monitoring plan may not be enforceable because of ambiguous
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EXHIBIT 4-5. EXAMPLE PERMIT LANGUAGE
FOR SITE-SPECIFIC MONITORING ACTIVITIES
^
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lite-specific- language;
Tie permittee shall monitor CSOs and report results to the permitting authority in accordance with the
allowing:
Characteristic
Reporting
Code








Units








Parameter
Ammonia
Ammonia
BOD5
BOD5
Phosphorus
Total Suspended
Solids
Total Suspended
Solids
Fecal Coliform
Bacteria
Monitoring Requirements
Measurement
Frequency








Sample Type
Grab
Composite
Grab
Composite
Composite
Grab
Composite
Grab

. The grab sample shall be collected within the first 30 minutes of the CSO event at the following CSO
outfalls {insert appropriate identification]. The grab sample shall be collected six times per year, three
times each during May - October and November - April.
. The composite sample shall be collected from the start of the CSO until the overflow stops, with the
sample period not to exceed 24 hours at the following CSO outfalls [insert appropriate identification].
Tlte composite sample shall be collected twice per year, once during the period from May - October
and once during the period from November - April. The permittee shall submit the results in November
and May, respectively.
continued implementation of the NMC, 2) progress reports associated with implementation of
CSO controls included in the LTCP, 3) monitoring data, and 4) other pertinent information
(e.g., sensitive area reassessment).
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    The recordkeeping requirements associated with the ongoing implementation of the NMC
have been incoiporated into the example permit language associated with minimum control
implementation (see Section 4.3.2).  The permit writer may choose to require reporting of any
of this information.   In addition, if the permit writer chooses to require any re-evaluations
associated  with  any  of the minimum controls, such  as a reassessment of the pretreatment
program  or additional revisions to the municipal ordinance, these reports may be required. In
addition, any reassessments required by the CSO Control Policy, such as the reassessment of
CSOs to  sensitive areas, should also be submitted to the permitting authority.  Permit language
associated with the submission  of this re-evaluation is included as a special condition in Section
4.9.2.

    Because the  implementation of the LTCP may  be  phased, the permit writer may require
progress  reports associated with the implementation of CSO control.  Exhibit 4-6 presents
example  permit language for requiring the submission of progress reports.
                      EXHIBIT 4-6. EXAMPLE PERMIT LANGUAGE FOR
                      REQUIRING SUBMISSION OF PROGRESS REPORTS
 Within 14 days of each completion date specified in [insert appropriate section] of this permit,
 the permittee shall submit a written progress report to the permitting authority stating whether or
 not the particular activity was completed. If the activity was not completed, the report shall also
 include (1) an explanation of the failure to accomplish the activity, (2) actions taken by the
 permittee to correct the situation, and (3) an estimate of when the activity will be completed.
   The permit writer should also require the permittee to submit monitoring data that focus on
protecting the public while CSO controls are being implemented.  Section 4.7 provides permit
language that includes reporting requirements for Phase II monitoring. The permit writer should
consider whether all applicable reporting requirements have been included in the Phase n permit.
Depending on  whether  the  permittee has chosen  to implement the  presumption or the
demonstration approach, for example, it may be appropriate to require the permittee to report
the number of overflow events or document other performance standards.  The permit writer
may also require that the permittee provide other environmental effectiveness data not otherwise
reported as part of the monitoring data, such as a reduction in the number of overflow events,
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reduction in number of CSO outfalls,  volume of CSO untreated/treated discharges, or other
improvements in receiving water quality.

4.9    SPECIAL CONDITIONS
   This section discusses three special conditions:  1) CSO-related bypasses, 2) sensitive area
reassessment, and 3) reopener clauses.  The sensitive area reassessment special condition should
appear in any CSO permit where a CSO discharges to a sensitive area and the permittee is not
planning to eliminate or relocate the CSO outfalls from that area.  The reopener clause should
appear in all Phase n permits.

4.9J  CSO-Related Bypass
   Some POTW treatment plants may have significant primary treatment capacity in excess of
their secondary treatment capacity.  During development of the LTCP, a community  may
consider, as a CSO control alternative,  using this excess primary treatment capacity rather than
constructing satellite primary clarification or its equivalent in the upper reaches of the CSS.  The
CSO Policy outlines a process whereby, under certain circumstances, the permit writer can allow
wet weather flows to receive primary clarification at the POTW treatment plant without these
flows being subject to secondary treatment requirements.

   According to the CSO Control Policy, the bypass requirements at 40 CFR Section 122.41(m)
may  be interpreted to authorize a generic bypass of the secondary treatment portion of the
POTW treatment plant for CSOs in certain limited circumstances.   For permittees with excess
primary capacity at the POTW treatment plant, the permit writer may consider including a CSO-
related bypass provision in the permit.  It should be noted, however, that the burden of proof
rests with the permittee (i.e.,  the permittee should provide the information and justification for
the bypass as part of their LTCP).  The CSO Control Policy recommends that the permittee"
.  . . provide justification for the cut-off point  at which  the flow will be diverted from the
secondary portion of the treatment plant, and provide an economic benefit analysis demonstrating
that conveyance of wet weather flow to the POTW for primary treatment is more beneficial than
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  1      other CSO abatement alternatives such as storage and pump back for secondary treatment, sewer
  2      separation, or satellite treatment."
  3
  4         Based on the technical justification developed and submitted by the permittee, the permit
  5      writer may include in the permit the  conditions under which a CSOrelated bypass would be
  6      approved,  as  well  as  specify any appropriate treatment,  monitoring, or effluent limitations
  7      requirements related to the bypass event.  All wet weather  flows passing the headworks of the
  8      POTW should receive at least primary clarification, solids and floatables removal and disposal,
  9      disinfection, where necessary, and any other treatment that can reasonably be provided.  The
10      permit writer should specify monitoring requirements to determine whether a substantial increase
11      in the volume or character of pollutants introduced to the POTW occurs. The permit writer may
12      also consider applying effluent limitations to flows that bypass the secondary treatment portion
13      of the treatment.  If the POTW is required to disinfect bypassed flows, then, assuming chlorine
14      is used to disinfect, the permit writer  may apply effluent limitations for total residual chlorine
15      to ensure protection of receiving water quality and compliance with water quality standards.
16
17         Due to the potential impact of bypasses, the permit writer should compile sufficient data and
18      information in the  administrative record and in the permit  fact sheet  or statement of basis
19      supporting all  the requirements in 40 CFR Section 122.41(m)(4) for approval of an anticipated
20      bypass.  Under the regulation, the permittee must  show that the  bypass  was unavoidable to
21      prevent loss of life, personal injury,  or severe property damage; that there was no  feasible
22      alternative to the bypass; and that the permittee submitted the required notices.  In addition,
23      according to the regulation, a bypass can only be approved after consideration of adverse effects.
24
25         For purposes of applying  the 40 CFR Section 122.41(m) requirements to CSO discharges,
26      "severe property damage" could include situations where flows above a certain level could wash
27      out the POTW's secondary treatment system.  The feasible alternative requirements of the
28      regulation can be met if the records demonstrate that the secondary treatment system is properly
29      operated and maintained, that the system has been designed to meet secondary  limits for flows
30      greater than the peak dry weather flow plus an appropriate quantity of wet weather flow, and


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that it is either technically or financially infeasible to provide secondary treatment for greater
amounts of wet weather flow.  The feasible alternative analysis should include, for example,
consideration of enhanced primary treatment and nonbiological secondary treatment. Other bases
supporting a  finding of no feasible alternative may also be available on a case-by-case basis.
As part of its consideration  of possible adverse effects resulting from the bypass, the permit
writer should also ensure that the bypass will not cause exceedances of WQS.

   The permittee must provide adequate justification for the CSO-related bypass and should
clearly define the wet weather flow conditions and flow rate at which  secondary  treatment
capacity  is exceeded.  In  addition, the permittee must demonstrate that bypassing secondary
treatment is  the  most beneficial  option,  in  light  of the  relative  cost to implement.   This
information should then be used by the permit writer to clearly define a site-specific CSO-related
bypass provision that includes the flow rate at which the CSO-related bypass will be allowed and
any treatment,  monitoring, or effluent  limitations or other  CSO-related bypass requirements.
The permit language should  indicate that CSO-related bypasses that occur under the flow upon
which the CSO-related bypass was authorized are subject to  the NPDES bypass provision at 40
CFR 122.41 (m).  The permit writer should also include supporting information in the permit fact
sheet or statement of basis.  Exhibit 4-7 presents an example of permit language for the CSO-
related bypass requirement.
       EXHIBIT 4-7.  EXAMPLE PERMIT LANGUAGE FOR A CSO-RELATED BYPASS
 A CSO-related bypass of the secondary treatment portion of the POTW treatment plant is
 authorized when the flow rate to the POTW treatment plant as a result of a precipitation event
 exceeds [insert flow rate in MGD]. The permittee must minimize pollutants discharged to the
 environment and all CSO-related bypass flows must receive primary clarification, solids and
 floatable removal, and disinfection. The permittee shall report any substantial changes in the
 volume or character of pollutants being introduced  into the POTW. This provision may be
 modified or terminated when there is a substantial change in the volume or character of pollutants
 being introduced to the POTW.
       Working Draft
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4,9.2  Reassessment of Sensitive Areas
    The CSO Control Policy states the permittee's LTCP should give the highest priority to
controlling CSOs to sensitive areas, as defined by the NPDES permitting authority in conjunction
with other Federal and State agencies.  The goal  for controlling CSOs to these areas  is to
eliminate the CSOs or relocate them whenever it is physically and economically possible.  If it
is not possible, then the permittee must treat the overflows that are not eliminated or relocated
to the degree necessary  to meet WQS.

    For overflows  to sensitive areas that were not  eliminated or relocated, the permit writer
should include in  the initial Phase n permit, and in subsequent permits, a special  condition
requiring the permittee to reassess the feasibility of doing so.  The permit writer should require
the  permittee to develop and submit a  report on this reassessment.  The permit writer should
require the permittee to evaluate the availability of new technologies that may  be  useful in
eliminating or relocating these CSOs and any changes in the permittee's economic situation that
would enable the permittee to fund the  required projects for eliminating or relocating the CSOs
from sensitive areas.

    Exhibit 4-8 provides example permit language for reassessment of sensitive areas for use in
Phase II and subsequent permits.
                    EXHIBIT 4-8. EXAMPLE PERMIT LANGUAGE FOR
                            SENSITIVE AREA REASSESSMENT
 For CSSs with CSOs to sensitive areas that were not eliminated or relocated:
 The permittee shall reassess the feasibility of eliminating or relocating CSO outfall numbers [insert
 outfall identification numbers for CSOs to sensitive areas] discharging to [insert name of
 receiving water body or bodies corresponding to each outfall identified].  The permittee shall
 address the economic and technical feasibility of eliminating or relocating these CSO outfalls. The
 permittee shall prepare and submit to the NPDES permitting authority a report that presents the
 results of this reassessment, including the permittee's recommendations regarding the elimination
 or relocation of these outfalls. The permittee shall submit such report no later than [insert date].
        Working Draft
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4.9.3  Permit Reopener Clause
    As with any NPDES permit, the Phase n NPDES permit should include a reopener clause
that authorizes the NPDES permitting authority to modify or revoke and re-issue the Phase n
permit for cause.  Potential CSO-related causes for exercising the reopener authority during the
Phase II permit term include a determination that the selected CSO controls fail to meet WQS
or the State  WQS  authority revises WQS  or  develops new WQS to address wet weather
conditions on the basis of a use attainability analysis.

    The permit  writer should coordinate  with the appropriate NPDES enforcement authority
when a Phase n permit is reopened.  Modifying the Phase n permit will require the modification
of any  enforcement mechanism issued with the Phase n permit for consistency with the modified
or re-issued Phase II permit.

    Before exercising any reopener provision, the permit writer should consider the timing of
the scheduled permit re-issuance.  If it is late in  the 5-year permit cycle (i.e., the last 2 years),
the permit writer may address the changes in the context of normal permit re-issuance process.
The NPDES permitting authority may have standard procedures that govern the use of reopener
clauses. The permit writer should follow these procedures when it is appropriate.

   It is possible that the generic reopener clause used  in other NPDES permits is  sufficiently
broad to address CSOs.  Alternatively, the permit writer may revise the generic reopener clause
to specifically include the CSO-related causes for which the Phase n permit may be reopened,
or the permit  writer may include a separate reopener clause that only identifies the CSO-related
causes  for which the Phase H permit may be reopened. Example language for the latter case
is presented in Exhibit 4-9.  For additional information  on the use of standard reopener clauses
in NPDES permits,  the permit writer should refer to the Training Manual for NPDES Permit
Writers (EPA, 1993).

4.10   DEFINITIONS
   See Section 3.11 for a list of terms  that may be appropriate to include in the permit.
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                EXHIBIT 4-9. EXAMPLE PERMIT LANGUAGE FOR REOPENER CLAUSES
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This permit may be modified or revoked and re-issued (1) to comply with any State or Federal law
or regulation that addresses CSOs that is promulgated subsequent to the effective date of the
permit, (2) when additional information indicates the CSO controls fail to meet State water quality
standards, (3) when the facility or CSO controls are substantially modified, or (4) for any other
valid reason pursuant to 40 CFR §122.62.


      Working Draft
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                                     CHAPTER 5
                             POST-PHASE n PERMITTING

5.1    CONTINUATION OF PHASE n
   The permit writer's responsibilities continue even after issuance of the first Phase n permit
requiring implementation of the selected CSO controls from the LTCP. Phase n, in many cases,
may extend through numerous 5-year NPDES permit cycles.  The number of additional cycles
will  depend on the length  of  time the permit writer, in conjunction  with  the permittee,
determines is necessary to complete construction of the selected CSO controls.  In cases where
construction will take more than 5 years, the permit writer must coordinate with the enforcement
authority to determine the appropriate enforcement  mechanism.

   The permit writer should continue to  include in  subsequent Phase n permits any conditions
that require the permittee to implement the selected CSO controls, continue implementation of
NMC, and require reassessment  of overflows to sensitive areas.  The requirement to implement
the post-construction compliance monitoring program should be included  in a Phase n permit
(because some CSO controls have been completed) or in the first post-Phase U permit). Chapter
4 provides specific  information on these Phase n permit conditions.

   The permit writer should continue to work closely with the permittee during these subsequent
permit cycles.  The permit writer should continue to require the permittee to periodically report
the status of implementation of the selected CSO controls (see Section 4.8).  Continued
involvement by the permit writer is critical to the development of the NPDES permit following
implementation of the selected CSO controls.

5.2    SUBSEQUENT CSO PERMITTING
   Prior to issuing the NPDES permit for the period in which the permittee's implementation
of selected CSO controls is  expected to be completed, the permit writer  should reach an
agreement with the permittee  on  the  implementation of  a  post-construction compliance
monitoring program (prepared during development of the LTCP) that will generate information
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  1      and data necessary to determine whether the selected CSO controls are achieving compliance
  2      with applicable State WQS. The permit writer will incorporate the requirement to conduct this
  3      post-construction monitoring program into the first NPDES permit issued following completed
  4      construction of the selected CSO controls.  Additionally, when enough water quality data have
  5      been generated, the  permit writer will use the data to develop numeric  water  quality-based
  6      effluent limits for inclusion in subsequent NPDES permits.
  7
  8         When using the data and information generated by the permittee under the Phase n permit(s)
  9      to develop numeric water quality-based effluent limits, the permit writer  should consider the
10      following questions:
11
12         •  Were CSO frequency and volumes estimated or  measured?
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14         •  Were all pollutants of concern  identified, including  toxics, and were  overflow
15            concentrations/loadings for each pollutant estimated or measured?
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17         •  Did the permittee  consider  the applicable State WQS?
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19         •  Were ambient background concentrations of pollutants of concern considered?
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21         •  Were appropriate receiving water flow values used? Many State WQS specify the flows
22            under which water quality criteria must be achieved.
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24         •  If applicable, were mixing zones calculated in accordance with State  standards or
25            policies?
26
27         •  Was the cumulative impact of multiple CSOs to the same receiving water body
28            considered?
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30         The permit writer may have additional information and data needs depending on the policies
31      and procedures used  by the NPDES permitting authority to evaluate water quality impacts and
32      develop  numeric  water  quality-based  effluent  limits.    It  should be  noted  that  the
33      scientific/technical issues  related to determining the need for water quality-based effluent limits
34      for CSOs  may  be  different  than  those commonly  used  by permit writers for continuous
35      wastewater discharges from other point source categories.  For example,  use of chronic criteria
36      designed for a particular low flow  scenario may not apply during wet  weather flow conditions

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when CSOs are likely to occur.  In addition, State WQS may have been revised to better reflect
receiving water body uses during  wet weather conditions.

    Therefore, it  is strongly  recommended that the permit writer involve appropriate WQS
authorities in evaluating whether CSOs will achieve WQS and developing numeric water quality-
based effluent limits.  The permit writer should also refer to the Technical Support Document
for Water Quality-based Toxics Control (EPA, 1991) for guidance in developing water quality-
based effluent limitations.

    Due  to the possible combined effect of pollutant sources (e.g., other point and nonpoint
sources)  or the existing receiving  water body condition, chemical-specific water quality-based
effluent limits established specifically for CSOs may not result in compliance with WQS for a
particular receiving water body.  In these cases, the permitting authority should include in the
permit a  total maximum daily  load (TMDL) for the receiving water body for pollutants in CSOs
exceeding WQS.  If a TMDL is established for a receiving water body to control all pollutant
sources,  the permit writer should base the numeric water quality-based effluent limits for a CSO
on the wasteload allocation established for each pollutant of concern.

    After the permittee has completed construction of the  selected CSO controls, the permit
writer can consider for use in  the last Phase n permit or in the first post-Phase n permit the use
of biocriteria,  sediment criteria, and whole effluent toxicity testing to evaluate the overall effect
of CSOs on receiving water bodies. Use  of these requirements will depend on the need to 1)
assess toxicity in the receiving water body, (2) prevent future impacts, or (3) remediate existing
receiving water body degradation.  Again, the permit writer should consult with the appropriate
State WQS authorities and enforcement staff to determine whether such requirements  in the
permit are warranted and to establish the specific requirements for the CSOs of concern.
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                                     APPENDIX  A
                               EXAMPLE CSO PERMIT
PHASE I PERMIT
The permittee is authorized to discharge from the CSO outfalls listed below and additional CSO
outfalls within the boundaries of the jurisdiction identified after the effective date of the permit.
The permittee shall ensure that all CSOs from the CSS comply with the requirements of [insert
appropriate permit section containing CSO requirements] and other pertinent portions of this
permit.
    Overflow Number   Overflow Outfall Location
    [insert number]
I. Effluent Limits
[insert latitude/longitude
(street address optional)]
                             Receiving Water Body
[insert receiving water body]
A. Technology-based requirements for CSQs

The permittee shall comply with the following technology-based effluent limits in the form of
narrative controls:

   1.  The permittee shall implement proper operation and maintenance programs for the sewer
       system and all CSO outfalls,  with consideration given to regular sewer inspections;
       sewer, catch basin, and regulator cleaning; equipment and sewer collection system repair
       or replacement, where  necessary; and disconnection of illegal connections.

   2.  The permittee shall implement procedures that will maximize use of the collection system
       for wastewater storage.

   3.  The permittee shall review and modify, as appropriate, the existing Pretreatment Program
       to minimize the impact of nondomestic discharges from CSOs.

       [Alternative language  for permittees without an approved Pretreatment Program.]

       The permittee shall take steps to  minimize the impact  of nondomestic discharges from
       CSOs.

   4.  The permittee shall operate the POTW treatment plant at maximum treatable flow during
       all wet weather flow conditions.  The permittee shall deliver all flows to  the treatment
       plant within the constraints of the treatment capacity of the POTW.
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    5.  Dry weather overflows from CSO outfalls are prohibited.  All dry weather overflows
       must be reported to the permitting authority as soon as the permittee becomes aware of
       the overflow.  When the permittee detects a dry weather overflow, the permittee shall
       begin corrective action immediately.   The permittee shall inspect the  dry  weather
       overflow each  subsequent day until the overflow has been eliminated.

    6.  The permittee  shall implement controls to remove solid and floatable materials in its
       CSOs.

    7.  The permittee shall implement a pollution prevention program focused on reducing the
       impact  of CSOs on receiving waters.

    8.  The permittee shall implement a public notification process to inform citizens  of when
       and where CSOs occur.  The process must include (a) a mechanism to alert persons of
       the occurrence of  CSOs  and (b) a  system  to determine the nature and duration of
       conditions that are potentially harmful for users of receiving waters due to CSOs.

    9.  The permittee shall  monitor CSO outfalls to effectively characterize CSO impacts and the
       efficacy of CSO controls. This information will be used to establish the existing baseline
       conditions, evaluate the efficacy of the CSO technology-based controls, and determine
       the baseline conditions upon which the long-term control plan will be based. These data
       shall  include:

       a.  All  CSO outfalls in the CSS
       b.  Total number of CSO events and the frequency, duration,  volume, and pollutant
          loadings of CSOs during each event
       c.  Water quality data for receiving water bodies
       d.  Water quality impacts (e.g., beach closings, floatables wash-up episodes, fish kills).

       Monitoring for duration, volume, and pollutant loadings during each overflow event shall
       occur at a representative number of CSOs.

B.  Water quality-based requirements for CSQs

The permittee  shall not discharge any pollutant at a level that could cause or contribute  to a
violation of [insert applicable State narrative standards] water quality standards.

    Site-Specific Language:

   All discharges covered by this permit shall be free from the following pollutants at levels that
    cause or contribute to a violation of water quality standards:

    1.  Floating debris, oil, grease, scum, foam, or other materials on  the water surface  that
       may create a nuisance condition,  or that may in any way interfere with attainment and
       maintenance of designated uses of the water
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    2.  Senleable solids, sediments,  sludge deposits, or suspended particles that may coat or
       cover submerged surfaces and create a nuisance condition, or that may in any way
       interfere with attainment and maintenance of designated uses of the water

    3.  Any  pollutants,  including  those of a thermal,  toxic, corrosive,  bacteriological,
       radiological,  or other nature, that may interfere with attainment and maintenance of
       designated uses of the water; may impart undesirable odors, tastes, or colors to the water
       or to aquatic life found therein; may endanger public health; or may result in dominance
       of nuisance species.

II. Reporting Requirements

A. Nine minimum CSO control reporting

The permittee shall submit documentation that demonstrates implementation of each of the nine
minimum CSO controls that includes the elements contained in Sections n.A.l through n.A.9
below.  The permittee shall submit this documentation to the permitting authority on or before
[insert due date].

    1.  Proper operation and regular maintenance programs. The permittee shall submit:

       a.  Identification of CSS components  requiring routine operation and maintenance
       b.  Evaluation of operation and maintenance procedures to include regular inspections;
          sewer, catch basin, and regulator  cleaning; equipment and sewer collection  system
          repair or replacement where necessary
       c.  Operation and maintenance manual and/or procedures for the CSS and CSO structures
       d.  Resources allocated (manpower, equipment, training) for maintenance of the CSS and
       e.
CSO structures
Summary of inspections conducted and maintenance performed.
    2.  Maximization of the sewer collection system storage. The permittee shall submit:

       a.  Analysis/study of procedures to maximize collection system storage
       b.  Description of procedures in place for maximizing collection system storage
       c.  Schedule for  implementation of minor construction associated with maximization of
          collection system  storage
       d.  Documentation of actions taken to maximize storage
       e.  Identification of any additional potential actions to increase storage in  the  existing
          collection system, but which require further analysis.  Confirmation that they will
          be/were evaluated in hydraulic studies conducted  as part of the long-term control
          plan.
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    3-  Review and modification of controls on nondomestic sources. The permittee shall submit:

       a.  Results of an inventory of nondomestic discharges and assessment of the impact of
          such discharges on CSOs
       b.  Identification and analysis  of feasibility  of  modifications  to  nondomestic source
          controls to reduce the impact of such discharges on CSOs
       c.  Documentation of selected modifications.

    4.  Maximization of flow to the POTW treatment plant for treatment. The permittee shall
       submit:

       a.  Study/analysis of existing conditions and a comparison with the design capacity of the
          overall facility
       b.  Results or  status of any  engineering studies  to increase treatment of wet weather
          flows
       c.  Documentation of actions taken to maximize flow and the  magnitude  of increase
          obtained or projected.

    5.  Elimination of CSOs during dry weather flow conditions.  The permittee shall submit:

       a.  Summary of dry weather overflows that occurred
       b.  Description of procedures for notifying permitting authority of dry weather overflows
       c.  Summary of actions  taken to  identify dry weather overflows and progress toward
          eliminating dry weather overflows.

    6.  Control of solid and floatable materials in CSOs.  The permittee shall submit:

       a.  Engineering evaluation of procedures or technologies  for  controlling solids  and
          floatable materials
       b.  Description of CSO controls in place for solids and floatable materials
       c.  Schedule for minor construction
       d.  Documentation of any additional controls to be installed or implemented.

    7.  Pollution prevention programs to reduce contaminants in CSOs.  The permittee shall
       submit:

       a.  Evaluation of pollution prevention opportunities to include procedures to control solid
          and floatable materials
       b.  Description of selected  pollution prevention opportunities to include resources
          allocated for implementation
       c.  Documentation of pollution prevention program or actions taken.
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    8.  Public notification.  The permittee shall submit:

       a.  Evaluation of public notification options to include description of proposed and/or
          existing public notification procedures
       b.  Description of selected public notification methods
       c.  Log of CSO occurrences and associated public notification.

    9.  Monitoring to characterize CSO impacts and efficacy of CSO controls .  The permittee
       shall submit:

       a.  Identification of CSO outfalls in the CSS
       b.  Summary of CSO occurrences (total number of CSO events and frequency, duration,
          volume, and pollutant loadings of CSOs during events).   Monitoring summary for
          duration,  volume, and pollutant loadings during each overflow event may portray a
          representative number of CSOs.
       c.  Summary of water quality data for receiving water bodies
       d.  Summary of receiving  water  impacts (e.g., beach  closings,  floatables  wash-up
          episodes,  fish kills,  etc.).

in.   Special  Conditions

The permittee  shall  develop the long-term CSO control plan that  will include the elements
contained in Sections m. A through ffl.D below and shall submit the plan elements in accordance
with the schedule contained in  Section m.E:

A.  Public Participation

The permittee shall prepare and implement a public  participation plan that outlines  how  the
permittee will ensure participation of the public throughout the long-term CSO control plan
development process. For purposes of this permit, the public includes, but is not limited to, rate
payers, industrial users of the sewer system, persons who reside near water bodies affected by
the CSOs, people who use and enjoy these affected waters, and any other interested persons.
In developing the plan, the permittee  shall consider the use  of mechanisms such as  public
meetings throughout the process of developing  a long-term CSO control  plan, including  the
process of selecting the  long-term CSO controls.  The long-term control plan shall include a
summary of each of the major  public participation events.

B.  CSS Characterization

The permittee  shall develop  and implement a plan that will  result in a  comprehensive
characterization of the CSS developed through  records review, monitoring, modeling, and other
means  as appropriate to establish the existing  baseline conditions, evaluate the efficacy of the
CSO technology-based controls, and determine the baseline conditions upon which the long-term
control plan will be based.  The characterization shall adequately address  the response of the
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 CSS to various precipitation events; identify the number, location, frequency, and characteristics
 of all CSOs; and identify water quality impacts that result from all CSOs.

 To complete the characterization, the permittee shall employ the following methods:

    1.  Rainfall Records Review.  The permittee shall examine the complete rainfall records for
       the geographic areas of the CSS and evaluate the flow variations in the receiving water
       body to correlate between the CSOs and receiving water conditions.

    2.  CSS Records Review.  The permittee shall review and evaluate all available CSS records
       and undertake Field inspections and other necessary activities to  identify the number,
       location, and frequency  of  CSOs and their  location  relative to sensitive  areas  (as
       identified in ffl.B.4) and to pollution sources, such as significant industrial users, in the
       collection system.

    3.  CSO Monitoring.  The permittee shall develop and submit a monitoring program that
       measures the frequency,  duration,  flow rate,  volume, and pollutant  concentration of
       CSOs and assesses the impact of the CSOs on receiving waters.  Monitoring shall be
       performed at a representative number of CSOs for the following parameters:  [insert
       pollutants of concern (e.g., biochemical oxygen demand, total suspended solids)].
       The  monitoring  program shall include  CSOs  and  ambient  receiving water  body
       monitoring and,  where appropriate, other monitoring  protocols, such  as  biological
       assessments, toxicity testing, and sediment sampling.

    4.  Identification of Sensitive Areas. The permittee shall identify sensitive areas to which
       its CSOs discharge.   These  areas shall include outstanding national  resource waters,
       National Marine Sanctuaries, waters with  threatened or  endangered species and their
       designated critical habitat, waters designated for primary contact recreational use, public
       drinking water intakes or their designated protection areas, shellfish beds, and any other
       areas identified by the permittee or the permitting authority.

    5.  Modeling.   The permittee may [shall] employ models, which include appropriate
       calibration and verification with field measurements, to aid in the characterization.  If
       models are used, they shall be identified by the permittee along with an  explanation of
       why the model was selected and used in the characterization.
C. CSO Control Alternatives

   1.  Development of CSO Control Alternatives.  The permittee shall develop a range of CSO
       control alternatives that would be necessary to achieve [insert levels of control, such as
       zero overflow events per year, an average of 1 to 3, 4  to 7, and 8 to 12 overflow
       events per year].  The permittee shall also consider expansion of the POTW treatment
       plant secondary and primary capacity  as an alternative.
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       Alternatives presented must give the highest priority to controlling CSOs to the following
       sensitive areas, identified in m.B.4.  For such areas, the alternatives included in the plan
       must (1) prohibit new or significantly increased CSOs, (2) eliminate or relocate CSOs
       from  such areas wherever  physically  and economically  achievable, except where
       elimination or relocation would provide less environmental protection than additional
       treatment,  (3)  where  elimination or relocation  is  not  physically or  economically
       achievable or would provide less environmental protection than  additional treatment,
       provide the level of treatment for remaining CSOs deemed necessary to  meet water
       quality standards for full protection of existing and designated uses.

    2.  Evaluation of CSO Control Alternatives.   The permittee shall evaluate each of the
       alternatives developed in accordance with IE.C.I  to select the CSO controls that will
       ensure compliance with  CWA requirements.

    3.  Cost/Performance   Considerations.    The  permittee  shall  develop  and   submit
       cost/performance curves  that  demonstrate the  relationship among  and the  cost
       effectiveness of the  CSO control alternatives.

D.  Selected CSQ Controls

Once the permittee has selected the CSO controls in consultation with the permitting authority,
the permittee shall submit the following:

    1.  Implementation Schedule.  The permittee  shall  submit  a construction schedule and
       financing plan for the selected CSO controls as part of  the  implementation schedule.
       Such schedules may be phased based on  the relative importance of the adverse impacts
       on water quality standards and on the permittee's financial capability.

    2.  Operation  andJMaintenance Plan.  The permittee shall submit a revised operation and
       maintenance plan that addresses implementation of the  selected  CSO controls.  The
       revised operation and maintenance plan shall maximize the removal of pollutants during
       and after each precipitation event using all available facilities within the collection and
       treatment system.

    3.  Post-Construction Compliance Monitoring Program.   The permittee shall develop and
       submit a post-construction monitoring program that (a) is adequate to ascertain the
       effectiveness of the  CSO controls and (b) can be used to  verify compliance with water
       quality standards.  The program shall  include a plan that details the monitoring protocols
       to be followed, including effluent and ambient monitoring and, where appropriate, other
       monitoring protocols, such as biological assessments, whole effluent toxicity testing, and
       sediment sampling.
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 E.  Schedule and Interim Deliverables

 The following reports shall be developed in accordance with the requirements specified in
 Sections ffl.A through IH.D and  submitted to the permitting authority by the dates specified
 below:

    1.  Public Participation Plan, as required in Section III.A, shall be submitted on or before
       [insert due date}.

    2.  CSS Characterization Monitoring and Modeling Plan, as required in Section ffl.B, shall
       be submitted on or before  [insert due date].

    3.  CSS Characterization Monitoring and  Modeling  Results,  including identification of
       sensitive areas, as required in Section m.B, shall be submitted on or before [insert due
       date].

    4.  CSO  Control  Alternatives Identification,  as required  in  Section  m.C.l,  shall be
       submitted on or before [insert due date].

    5.  CSQ Controls Evaluation and Cost Performance Curves for the selected CSO controls,
       as required in Sections ffl.C.2 and 3,  shall be submitted on or before [insert due date].

    6.  Implementation Schedule,  as required in Section HI.D.I,  including the affordability
       analysis, shall be submitted on or before [insert due date].

    7.  Operational Plan revised to reflect selected  CSO control alternatives, as required in
       Section III.D.2, shall be submitted on or before [insert due date].

    8.  Post-Construction Compliance Monitoring Program, as required in Section IQ.D.3, shall
       be submitted on or before [insert due date].

Reopener Provision

This permit may be modified or revoked and reissued to comply with any State or Federal law
or regulation that addresses CSOs and that is promulgated subsequent to the effective date of the
permit,  or if additional information indicates CSO controls fail  to contribute to the attainment
of State water quality standards.  In addition, upon  satisfactory completion of the LTCP, the
permit may be modified or revoked and reissued to require implementation of the selected CSO
controls.
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 PHASE II PERMIT

 The permittee is authorized to discharge from the CSO outfalls listed below in accordance with
 the requirements of [insert appropriate CSO section references] and other pertinent provisions
 of this permit.
    Overflow Number    Overflow Outfall Location
    [insert number]
 I.  Effluent Limits
[insert latitude/longitude
(street address optional)]
                              Receivine Water Body
[insert receiving water body]
 A.  Technology-based requirements for CSOs

 The permittee shall comply with the following technology-based effluent limits in the form of
 narrative controls:

    1.  Conduct  proper operations and regular maintenance programs.   The permittee shall
       implement the Operation and Maintenance Plan for the combined sewer system that will
       include the elements listed below.  The permittee also shall update the plan to incorporate
       any changes to the system and shall operate and maintain the system according to the
       plan.  The permittee shall keep records to document the implementation of the plan.

       Site-Specific Language:

       Designation of a Manager for Combined Sewer Overflows. The permittee shall designate
       a person to be responsible for the wastewater collection  system and serve as the contact
       person regarding combined sewer overflows.  The permittee shall notify the permitting
       authority within [specify number of days] of designation of a new contact person.

       Inspection and Maintenance of CSS. The permittee shall inspect and maintain all CSO
       structures, regulators, pumping stations, and tidegates  to ensure  that they are in good
       working condition  and adjusted to minimize  CSOs and prevent  tidal  inflow.   The
       permittee sliall inspect, or cause to be inspected,  each CSO outfall at least [specify
       frequency for inspection].   The inspection shall include, but is not  limited to, entering
       the regulator structure if accessible, determining the extent of debris and grit build-up,
       and removing any debris that may  constrict flow, cause blockage,  and result in a dry
       weather overflow.   The permittee shall record in a maintenance log book the results of
       the inspections.  For CSO outfalls  that are inaccessible, the permittee may perform a
       visual check of the overflow pipe to determine whether or not the CSO  is occurring
       during dry weather flow conditions.
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       Provision for Trained Staff.  Tiie permittee shall provide an adequate number of full-time
       equivalents to carry out the operation, maintenance,  repair, and testing Junctions
       required to ensure compliance with the terms and conditions of this permit.  Each
       member of the staff shall receive appropriate training.

       Prioritization Maintenance  Needs.   The permittee shall develop a prioritized  list of
       maintenance needs and a proposed implementation schedule.  The permittee shall submit
       this list to the permitting authority within [insert number] months of the effective date of
       the permit.

       Allocation of Funds for Operation  and Maintenance.   The permittee shall allocate
       adequate funds specifically for operation and maintenance activities. The permittee shall
       submit a certification of assurance from the affected local government entities that the
       necessary funds, equipment, and personnel have been or will be committed to carry out
       the O&M plan.

    2.  Maximize use of the collection system for storage. The permittee shall maximize the in-
       line storage capacity.  The permittee shall keep records to document implementation.

       Site-specific language:

       The permittee shall 1) maintain all dams at diversion structures at their current heights
       (as of the date of permit issuance) or greater, 2) minimize discharges from the CSO
       outfall locations designated as [insert appropriate designation] until the entire available
       capacity of the [named] Combined Sewer Retention Basin is used to store the overflow
      for later treatment at the plant, and 3) keep  records of the flow entering and leaving the
       [named] Combined Sewer Retention Basin.

    3.  Review and modify pretreatment program.  The permittee shall continue to implement
       selected  CSO controls to minimize the  impact of nondomestic discharges from CSOs.
       The permittee shall re-evaluate [specify  frequency] whether additional modifications to
       its pretreatment program are feasible or of practical  value.  The permittee shall keep
       records to document this evaluation and implementation of the selected CSO controls to
       minimize nondomestic discharges from CSOs.

       Site-specific language:

       The permittee  shall prohibit the  addition of new or  increased volumes  of industrial
       process or high-strength wastewaters into the sewer system  under  circumstances  where
       they could be discharged through a CSO outfall.
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       Alternative language for permittee without an approved pretreatment program.

       Actions to minimize impact of nondomestic discharges from CSOs.  The permittee shall
       continue to implement selected CSO controls to minimize the impact of nondomestic
       discharges from CSOs.

    4.  Maximize flow to  POTW treatment plant.  The permittee shall operate the POTW
       treatment plant at maximum treatable flow of at least [insert appropriate number] MOD
       during wet weather flow conditions/events and deliver all flows to the treatment plant
       within the constraints of the capacity of the treatment plant. The permittee shall keep
       records to document these actions.

    5.  Prohibit combined  sewer overflows during dry weather.  Dry weather overflows from
       CSO  outfalls are prohibited.   All dry weather overflows must be reported to the
       permitting authority within [insert appropriate number of days] of when the permittee
       becomes aware of a dry weather overflow.  When the permittee detects  a dry weather
       overflow, the permittee shall begin corrective action immediately.  The permittee shall
       inspect the dry weather overflow each subsequent day  until  the overflow  has been
       eliminated. The permittee shall record in the inspection log book dry weather overflows,
       as well as the cause, corrective measures taken,  and the dates of beginning and cessation
       of overflow.

    6.  Control solid and floatable materials in CSQs.  The permittee shall implement measures
       to control solid and floatable materials in its CSOs.

       Site-specific language:

       These measures shall include:

       (i)     Ensure that  all overflows from the diversion structures are baffled or that other
              means are used to reduce the volume offloatables.
       (ii)     Inspect and maintain the sewer system so that solids or floatable material greater
              ituin [insert  size] are not present in CSOs.
       (Hi)    Remove solid or floatable materials captured by a  [insert appropriate number]-
              inch screen  and dispose of this material in an  acceptable  manner prior to
              discharge to the  receiving water.   Overflows containing solid or floatable
              materials that may be captured by a [insert appropriate numberj-inch screen are
              prohibited.

    1.  Develop and implement pollution prevention program. The permittee shall implement
       a pollution prevention program focused on reducing the impact of CSOs on  receiving
       waters.    The  permittee  shall  keep  records  to  document pollution  prevention
       implementation activities.
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       Site-specific language:

       This program shall include:

       ft)     Conducting street sweeping  and catch basin modification  or cleaning  at  a
             frequency that will prevent large accumulations of pollutants and debris, but no
              less than [specify a minimum frequency]
       (ii)    Conducting a public education program that informs the public of the permittee's
              local laws that prohibit littering and the use of phosphate-containing detergents
              and pesticides
       (in)    Instituting an oil recycling program.

    8.  Notify the public of CSQs. The permittee shall continue to implement a public
       notification plan to inform citizens of when and where CSOs occur.  The process must
       include:

       a.  A  mechanism to alert persons using all receiving water bodies affected by CSOs
       b.  A  system to  determine the nature and duration of conditions that are  potentially
          harmful to users of these receiving water bodies due to CSOs.

       The permittee shall keep records documenting public notification.

       Site-specific language:

       Within 3 months of the  effective date of this permit, the permittee shall install and
       maintain identification signs at all CSO outfalls owned and operated by the permittee.
       The permittee must place the signs at or near the CSO outfalls and ensure that the  signs
       are easily readable by the public.  The signs sfiall be a minimum of 12 by 18 inches  in
       size, shall be metal, and shall contain the following information:  1) permittee name;  2)
       wet weather sewage discharge; 3) outfall (discharge serial number); and 4) telephone
       number and contact,

    9.  Monitor to effectively characterize CSO impacts and the efficacy of CSO controls.  The
       permittee shall regularly  monitor CSO outfalls to effectively  characterize CSO impacts
       and efficacy of CSO controls.

       Site-specific language:

       [For example language,  see Section II

B.  Water quality-based requirements for CSOs

The permittee shall comply with the  following performance standards.   These standards shall
apply during  [insert average design conditions under which controls are based upon].
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    1.  [The permit writer should select the appropriate standard below.]

       The permittee shall discharge no more than an average of [insert appropriate number:
       4, 5, or 6] overflow events per year not receiving the equivalent of primary clarification.

                                          or

       The permittee shall capture for treatment, or storage and subsequent treatment, at least
       85 percent of the  system-wide combined sewage  volume collected in the combined
       sewage system during precipitation events under design conditions.  Captured combined
       sewage shall be directed either to the [insert name of treatment plant(s)] or to the CSO
       storage tanks located at [insert  location of storage  tanks].

                                          or

       The permittee shall reduce the mass of the following pollutants  [insert pollutants] that
       have been identified as causing water quality standard violations for at least 85 percent
       of the system-wide combined sewage volume collected in the combined sewage system
       during precipitation events under design conditions.

 [Insert the following language only if the first or second alternative is chosen above.]

 Any combined sewage captured shall receive  a minimum of the following treatment:

    (i)     Primary clarification or equivalent.
    (ii)    Disinfection.  Fecal coliform counts shall be maintained  below  [insert applicable
          level]. [Insert appropriate dechlorination requirements if applicable based on
          State water quality standards.]

 II. Monitoring and Reporting

    Site-specific language:

    The permittee shall  monitor  CSOs and report  results to the permitting authority in
    accordance with the following:
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Characteristic
Reporting
Code








Units








Parameter
Ammonia
Ammonia
BOD5
BOD5
Phosphorus
Total Suspended
Solids
Total Suspended
Solids
Fecal Coliform
Bacteria
Monitoring Requirements
Measurement
Frequency








Sample Type
Grab
Composite
Grab
Composite
Composite
Grab
Composite
Grab
   /.  The grab sample shall be collected within the first 30 minutes of the CSO event at the
      following CSO outfalls [insert appropriate identification].  The grab sample shall be
       collected six times per year, three times each during May - October and November -
       April.

   2.  The composite sample shall be collected from the start of the CSO until the overflow
       stops, with the sample period not to exceed 24 hours at the following CSO outfalls
       [insert appropriate identification].  The composite sample shall be collected twice per
       year, once during the period from May - October and once during the period from
       November - April.   The permittee  shall submit the results in November and May,
       respectively.

in.    Special Conditions

A. Long-Term Control Plan

The permittee shall implement and effectively operate and maintain the selected CSO controls
in the long-term control plan. The implementation schedule for this program shall be as follows:
          Activity
          [insert name of activity]
 Completion Date
 [insert date]
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    Site-specific language:

    1,  Retention basin

       a.  Complete design of [named] retention basin.
       b.  Submit construction drawings for [named] retention basin.
       c.  Initiate construction of [named] retention basin.
       d.  Complete construction of [named] retention basin.

    2.  Main street sewer separation

       a.  Complete design.
       b.  Solicit bids.
       c.  Award contracts.
NOTE:  A compliance schedule exceeding the term of the permit may only be included in
the permit if allowed by State WQS.
Within 14 days of each completion date specified in [insert appropriate section] of this permit,
the permittee shall submit a written progress report to the permitting authority stating whether
or not the particular activity was completed. If the activity was not completed, the report shall
also include (1) an explanation of the failure to accomplish the activity, (2) actions taken by the
permittee to correct the situation, and (3) an estimate of when the activity will be completed.

B.  CSO-Related Bypass

A CSO-related bypass of the secondary treatment portion of the POTW treatment plant is
authorized when the flow rate to the POTW treatment plant as a result of a precipitation event
exceeds [insert flow rate in MGD]. The permittee must minimize pollutants discharged to the
environment and all CSO-related bypass flows must receive primary clarification, solids and
floatable removal,  and disinfection.  The permittee shall report any substantial  changes  in the
volume or character of pollutants being introduced into the POTW.  This provision may be
modified or terminated  when there is a substantial  change in  the  volume or  character of
pollutants being introduced to the POTW.

C.  Reassessment of CSQs to Sensitive Areas

For CSSs with CSOs to sensitive areas that were not eliminated or relocated:

    The permittee shall reassess the feasibility of eliminating or relocating CSO outfall numbers
    [insert outfall identification numbers for  CSOs to sensitive areas] discharging to [insert
    name of receiving water body or bodies corresponding to each  outfall identified]. The
    permittee shall address the economic and technical feasibility of eliminating or relocating
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    these CSO outfalls.   The permittee  shall  prepare and  submit to the NPDES permitting
    authority a report that presents the results of this reassessment,  including the permittee's
    recommendations regarding the elimination or relocation of these outfalls. The permittee
    shall submit such report no later than [insert date].

Reopener Provision

This permit may be modified or revoked and re-issued (1) to comply  with any State or Federal
law or regulation that addresses CSOs that is promulgated subsequent to the effective date of the
permit, (2)  when additional information  indicates the CSO controls fail to meet State water
quality standards, (3) when the facility or CSO controls are substantially modified, or (4) for any
other valid reason pursuant to 40 CFR §122.62.
Working Draft                          A-16                           April 6, 1994

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                 WORKING DRAFT:  Do NOT CITE OR QUOTE
                                     APPENDIX B
                  DEVELOPMENT AND REVIEW OF MONITORING PLAN

    The permit writer may require the permittee to develop a monitoring plan.  This may be
required during the application process prior to the development of the permit or as a permit
condition.  If, during the review of the plan, the permit writer determines the plan is lacking
information or  the scope of the  plan  is inappropriate,  the permit writer  should note the
deficiencies and require the plan to be modified and resubmitted.  Modification may require an
iterative approach to match data and informational needs with available resources.

    Exhibit B-l  outlines the major elements the monitoring plan should contain.  The permit
writer should consider  requesting that the permittee  submit  the monitoring plan in  a specific
format so  that critical information can be taken from  the plan and incorporated into the permit
as requirements.  Extensive information  on the development of a monitoring plan is contained
in the Combined Sewer Overflows—Monitoring and Modeling Manual (EPA,  1994).

    The monitoring plan should balance the costs of monitoring against the information needed
to develop, implement,  and verify the effectiveness of CSO control.  The size and type of the
monitoring program should be indicative of the size of the CSS in conjunction with the impacts
caused by the CSOs. The permit writer should remember this when reviewing any proposed
monitoring program.   Flexibility  should  be  provided to allow for scheduling and budget
constraints.  The permit writer should not  accept an inadequate monitoring plan,  however. A
review team that has members knowledgeable in developing and implementing monitoring
programs should be convened to review a proposed monitoring plan. If the proposed monitoring
plan does  not meet the established  goals, the permit writer should raise these issues and work
with the permittee to develop a more reasonable  monitoring plan that meets the established
objectives. In addition, in some instances, the permit writer and/or the permittee may need to
establish priorities  to perform  the most critical data collection first  and schedule  additional
monitoring requirements within a reasonable timeframe.
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April 6, 1994

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                   WORKING  DRAFT:  Do NOT CITE OR QUOTE
            EXHIBIT B-l.  OUTLINE or MAJOR MONITORING PLAN ELEMENTS
  A. Identification of Monitoring Goals and Objectives

     1.  Data and information collection goals and objectives (e.g., water quality impacts,
         characterization, modeling)
     2.  System components or parameters for which monitoring data are needed
     3.  Kinds of data needed to meet goals and objectives
     4,  Quality of data needed to meet goals and objectives
     5.  Limits of variability in system conditions to be characterized

  B. Existing Characterization Data and Information

     1.  Summary of existing data  and information
     2.  Determination of how existing data address goals and objectives
     3.  Identification of data gaps

  C. Sampling Program

     1.  Sampling locations
     2.  Sampling period
     3.  Frequency of sampling and/or number of precipitation events to be sampled
     4.  Flow measurement protocols  (estimated or measured)
     5.  Criteria for when the samples will be taken (e.g., greater than x days between precipitation
         events)
     6.  Sampling protocols (e.g., type of samples, chain of custody)
     7.  Pollutants or parameters to be analyzed and/or recorded
     8.  Analytical methodologies and detection limits

  D. Analytical Tools

     1.  Statistical methods for data analyses
     2.  Models used, input, calibration and validation

  E.  Implementation of Monitoring Plan

     1.  Scheduling
     2.  Funding resources
   When reviewing a monitoring plan and developing permit monitoring requirements, the
permit writer should  consider  sampling locations,  pollutants to be monitored,  frequencies,
periods of rainfall or other seasonal issues, sample types, and analytical methods, among other
factors.  These factors are described in the following discussion using examples.  The specific
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B-2
April 6, 1994

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                  WORKING DRAFT:  Do NOT CITE OR QUOTE
 sampling details are important because the permit writer may want to incorporate them into the

 permit:
    •  Sampling Location.  When monitoring CSOs or receiving waters, a defined percentage
       of the total outfalls in the system should be sampled.  The specific number of outfalls to
       be monitored should be based on the size of the collection system, the total number of
       overflow locations, the number of different receiving water bodies, and potential and
       known impacts.  In  large systems, a percentage of overflow points may be monitored
       (e.g., approximately  10 to 25  percent).   If only selected locations are  sampled, they
       should represent the system as a whole or represent the worst-case scenario.   For
       example, if all CSOs are not monitored, selected locations could be chosen that represent
       overflows that occur most frequently, are the largest in pollutant loading or flow/volume,
       or discharge to sensitive areas.

    •  Pollutants.  The five pollutants or class  of pollutants recommended for  monitoring  in
       most cases include BOD,  TSS, nutrients, toxic pollutants reasonably expected to be
       present, and bacteriological indicators.   In some cases,  specific pollutants should be
       measured; in other cases, surrogates of a pollutant class may be used.  For example,
       heavy metals may be addressed by only monitoring copper, lead, and zinc because these
       are the metals most commonly found in CSOs.  If WQS for mercury and arsenic are
       being exceeded, however, then  they should be monitored.  The selection of pollutants  to
       be monitored should also be based on the characteristics of the nondomestic discharges
       to the collection system or watershed.

    •  Frequency of Monitoring.  Frequency of monitoring should reflect the type and amount
       of data needed to achieve the goals.  Monitoring programs may include:

       -  Sampling a certain size precipitation event (e.g., 24-hour, 2-year storm)
       -  Sampling all precipitation events that result in overflows
       -  Sampling a certain number of precipitation events per period of time
       -  Sampling on a periodic basis.

       The precipitation events to be sampled should be separated by an adequate duration so
       that a sample of worst-case conditions is collected.  The NPDES Storm Water Program
       uses the criterion that the duration between the precipitation event sampled and the end
       of the previous measurable precipitation event be at least 72 hours.

       An assessment of the monitoring frequency should include consideration of the following
       criteria:

          Frequency of rainfall/discharge.   Facilities located in areas where rainfall is more
          frequent will have more frequent CSOs.
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April 6, 1994

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       -  Relative risk of CSO impacts.  If facilities discharge to sensitive areas or high quality
          waters, more frequent monitoring may be necessary. For example, in an area where
          human contact occurs through swimming, boating,  and other recreational activities,
          the monitoring frequency should be increased.
       -  Compliangg history.  If facilities have a history of noncompliance with NPDES
          permit conditions,  more frequent monitoring may  be necessary.   If the  facility is
          always in compliance, monitoring frequency can be reduced.
       -  Variability  of discharge.  CSOs with variable characteristics should be monitored
          more frequently than CSOs with relatively consistent characteristics.

    •  Duration of Monitoring Program.  The sampling period should be based on the amount
       of information  needed and time it takes to collect the information. The sampling period
       for flow and occurrence monitoring may extend  for  the duration of the permit;  the
       sampling period for instream monitoring or other special studies may be relatively short.
       When feasible, permit writers should coordinate monitoring requirements if the data will
       be used for the same purpose (e.g., compliance with WQS or calculation of a wasteload
       allocation).

    *  Sample Type.  The sample type may be composite or grab,  depending on the intended
       use of the data.  To determine the average loadings of pollutants to the receiving stream,
       it may be most appropriate to collect flow-weighted composites.  Because CSOs may be
       intermittent and the volume dependent upon precipitation events, however, it may not be
       appropriate to  collect  24-hour composite  samples,  which are  used  for continuous
       nondomestic and municipal wastewater discharges.  Instead it may be more appropriate
       to collect a composite over the duration of the entire discharge.   The permit writer must
       require sample  types that will adequately characterize CSOs.  However, the permit writer
       should be aware that  the composite samples are  more  resource intensive  than grab
       samples. Grab samples may be appropriate if only approximate levels of pollutants are
       needed or if the most important concern is the impact of worst-case conditions (i.e., first
       15 or 30 minutes of overflow).

    •  Analytical Methods.   Analytical  methods should be selected pursuant to 40  CFR Part
       136,  which references one or more of the following:

       -   Test methods in Appendix A to 40 CFR Part 136
       -   Standard Methods for the Analysis of Water and Wastewater (Edition Referenced)
       -   Methods for the Chemical Analysis of Water and Wastes
          Test Methods: Methods for Organic Chemical Analysis of Municipal and Industrial
          Wastewater.

       The analytical methods contained in 40 CFR Part 136 are test methods designed only for
       chemical-specific pollutants.  For other parameters, it may  be necessary to specify  the
       analytical  methods required.   For  example,  40 CFR Part  136 does  not  contain
       biomonitoring test procedures; therefore, the permit writer will need to specify  the
       methods.  EPA has published recommended toxicity test protocols in three manuals:
Working Draft                           B-4                            April 6, 1994

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                  WORKING DRAFT:  Do NOT CITE OR QUOTE
       Methods for Measuring  the  Acute Toxicity  of Effluents and  Receiving  Waters to
       Freshwater and Marine Organisms, Short-Term Methods for Estimating the Chronic
       Toxicity of Effluents, and Receiving Waters to Marine and Estuarine Organisms. EPA is
       revising methods for chronic toxicity testing and amending the regulations at 40 CFR
       Part 136 to add the whole effluent toxicity  procedures  to the already promulgated
       analytical test methods.
    The permit writer should also determine whether models or data analysis methodologies
specified in the monitoring are appropriate for the CSS and the type of data being collected.  If
the monitoring objectives include informational needs; modeling; or statistical, graphical, or
other data  analyses,  techniques should be specified so reliable and consistent information  is
obtained.  This will ensure that data collection efforts meet the needs of the analyses methods.
Review by the appropriate members of the review  team  (i.e., statisticians or other experts in
monitoring program development  and implementation)  will ensure that the  proposed data
collection and analytical methodologies  will meet the  stated  objectives of the monitoring
program.

    Each plan  will need to be evaluated on a case-by-case basis. The permit writer may enlist
the EPA Regional Environmental Sciences Division  staff in reviewing the monitoring plans
submitted by the perittee. If the review team determines that the proposed monitoring program
is inadequate,  then the permit writer should work with the permittee to revise the program to
address its deficiencies.
Working Draft                           B-5                             April 6, 1994

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              WORKING DRAFT: Do NOT CITE OR QUOTE
                             APPENDIX C
              NINE MINIMUM CONTROLS EVALUATION CHECKLIST
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Proper Operation and Regular Maintenance
Programs for the CSS and CSO Outfalls









Does the O&M program describe the system, identifying
and addressing CSOs by including an inventory of all
CSO structures, equipment, and treatment facilities and
provide procedures for keeping this inventory current?









Will the program be effective in reducing the number,
frequency, and pollutant loading due to CSOs?









Does the program provide operating procedures and
specifications for all equipment, structures, facilities,
CSO outfalls, and off-line storage structures, including
the hydraulic capacities of the collection and treatment
systems, the storage capacities of the collection and
treatment systems, and off-line storage capacity?









Does the program include routine inspection,
maintenance, and repair schedules for all CSO outfalls,
interceptors, pumping stations, and equipment and are
they appropriate for the system?









Does the program involve maintenance procedures,
including routine inspections, schedules for collection
system preventative maintenance, schedules for cleaning
and flushing of system and equipment, and response
procedures for repairs?









Does the program require logs or other documentation
of completed activities?









Does the program address the location of overflows
where O&M is hindered (i.e., devices are under major
thoroughfares, railroad yards, or other difficult to reach
or safety hazard areas)?
Working Draft
C-l
April 6, 1994

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Evaluation Criteria








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Does the program allocate resources for
implementation, including staffing level
equipment, and training?


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Has Ihe permittee identify portions of th
storage and determined the CSS storage
including configuration, size, and pump









to increase
Identify appropriate minor modifications
storage (e.g., raised existing weirs)?









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| Identify potential off-line storage at extsl









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capacity?


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Has the permittee determined if the CSS
nondomestic wastewater discharges?








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discharge to the same receiving water be
and evaluated the discharge constituents
impacts from such users?








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Evaluated the potential for regulating eit
or pollutant loadings from nondomestic i
during wet weather flow conditions?
Working Draft
C-2
April 6, 1994

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             WORKING DRAFT: Do NOT CITE OR QUOTE

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Evaluation Criteria








Has the permittee evaluated (he following technologies
for the removal of solid and floatable material:
Screening materials using baffles, screens, and
netting?








Skimming from water body surface with booms
at outfalls in confined areas?








Source control, which may be addressed under
the pollution prevention program for CSO
outfalls?








Identified and addressed problems that may be created
by the installation of the control technology?








Implemented the appropriate control technology,
considered and provided justification that the technology
is appropriate for the site conditions, and is conducting
associated inspections and regular maintenance?


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Pollution Prevention Program








Has the permittee evaluated both government agency
(e.g., street cleaning, banning, or substitution of
products, such as plastic food containers; controlled use
of pesticides, fertilizers, and other hazardous substances
at public facilities) and public (e.g., used oil recycling,
household hazardous waste collection) source control
measures?








Addressed pollutants found in CSOs during the
evaluation of the control measures?








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Working Draft
C-3
April 6, 1994

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             WORKING DRAFT: Do NOT CITE OR QUOTE




valuation Checklist
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Evaluated mechanisms to encourage water conserv
(e.g., public outreach, structuring of water/sewer
service charges, local ordinance provisions)?













Allocated adequate resources to conduct pollution
prevention program activities?













Implemented and maintained detailed records of
pollution prevention activities?











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Promoted the use of industrial/construction BMPs
stormwater?




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1 Public Notification





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Has the permittee evaluated options for public
notification to ensure that the public receives adeqi
notification of CSO occurrences and CSO impacts'










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Implemented procedures that safeguard the public
through public notification of the presence of
contaminants at critical levels in the receiving waU
bodies due to CSOs?











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Documented CSO occurrences and associated
notifications?













| Installed identification signs at each CSO outfall?




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Evaluation Result (circle one)
Working Draft
C-4
April 6, 1994

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             WORKING DRAFT: Do NOT CITE OR QUOTE




uation Checklist
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Monitoring to Effectively Characterize CSO Impac
and Efficacy of CSO Controls










Has the permittee characterized the CSS to identify al
CSO locations and receiving water bodies?










Collected data on the total number of overflow events
and the frequency, duration, volume, and pollutant
loadings of CSOs?










Collected water quality data and information on water
quality impacts (e.g., beach closings, floatables, wash
up episodes, fish kills)?










Conducted monitoring to determine baseline data prio
to implementation of the NMC?









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Conducted monitoring to determine baseline condition
subsequent to implementation of the NMC, which ma;
be used in LTCP development?




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Working Draft
C-5
April 6, 1994

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              WORKING DRAFT:  Do NOT CITE OR QUOTE
                             APPENDIX D
             LONG-TERM CONTROL FLAN EVALUATION CHECKLIST

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Evaluation Criteria




Public Participation




Does the public participation process seek to
actively involve rate payers, industrial users of
the CSS, persons near the impacted waters, and
persons who use the impacted waters?




Does the public participation plan document how
the public was notified of public participation
events?
•



Does the public participation plan include a
record of the public participation events, -
including the number of people attending and a
record or summary of comments?




Does the public participation plan contain a
summary of comments and the changes or
decisions nude in response to public comments?

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Adequate
Evaluation Result (circle one)




CSS Characterization, Monitoring, andi
Modeling




Is there a general description of the CSS that
includes the geographical area and population
served?




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Is there information on the volume, flow rate,
and frequency of CSOs and the pollutants
discharged?


Working Draft
D-l
April 6, 1994

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             WORKING DRAFT:  Do NOT CITE OR QUOTE
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Working Draft
                    D-2
                                         April 6, 1994

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            WORKING DRAFT: Do NOT CITE OR QUOTE
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Working Draft
D-4
              April 6, 1994

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           WORKING DRAFT: Do NOT CITE OR QUOTE
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D-5
                        April 6, 1994

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            WORKING DRAFT: Do NOT CITE OR QUOTE

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Working Draft
D-6
                                    April fj, 1994

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            WORKING DRAFT:  Do NOT CITE OR QUOTE
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Working Draft
D-7
April 6, 1994

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