UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
WASHINGTON. D.C. 20460
DEC U 18S2
Dear Colleague:
Enclosed is a-Draft Combined Sewer Overflow. Control Policy.
A Notice of Availability, providing for a 60-day public comment
period, will be published in the Federal Register in the near
future.
The main purposes of the. Policy are to elaborate on the?
Environmental Protection Agency/s (EPA's) National Combined Sever
Overflow Control Strategy published on September 8, 1989, at
54 FR 37370, and to expedite compliance with the requirements of
the Clean Water Act (CWA). While implementation of the 1989
Strategy has resulted in progress toward controlling combined
sever overflows (CSOs), significant public health and water
quality risks remain.
The Policy is being developed to provide guidance to
permittees with CSOs, National Pollutant Discharge Elimination
iSystem (NPDES) authorities and State water quality standards
authorities, on coordinating the planning, selection/sizing and
construction of CSO controls that meet the requirements of the
CWA and allow for public involvement during the decision-making
process. •
Contained in the Policy are provisions for developing
appropriate, site-specific NPDES permit requirements for all
combined sewer systems that overflow as a result of wet weather
events and enforcement initiatives to require the immediate
elimination of overflows that occur during dry weather, and to
ensure that the remaining CWA requirements are complied with as
soon as practicable.
The permitting provisions of the Policy were developed as a
result of. extensive input received during a negotiated policy
dialogue. The negotiated dialogue was conducted by the Office of
Water and the Office of Water's Management Advisory Group.
Representatives from State, environmental and municipal
organizations participated in the negotiated dialogue.
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The enforcement initiatives, including one to be initiated
in 1993 on CSOs during dry weather, were developed by EPA's
Office of Water and Office of Enforcement.
The major provisions of the Policy are:
C80 permittees should immediately undertake a process to
accurately characterize their combined sewer system,
demonstrate implementation of nine minimum? controls, and
develop a long-term CSp control plan. Once the long-term
CSO control plants cbttpleted; the permittee will be
responsible to implement the plan's recommendations as soon
as practicable;
State water quality standard (WQ8) authorities should be
involved in the long-term CSO control planning effort to
coordinate the review and possible revision of WQS and
implementation procedures on CSO-impacted waters with the
development of the long-term CSO control plan; .
" * ' ' .'-";•-
NPDES authorities should issue/reissue permits to require
immediate compliance with the technology-based and water
quality-based requirements of the CWA, and after completion
°LS? long-term CSO control plan, incorporate the following
additional permit requirements ~ performance standards for
the selected controls based on average design conditions, a
post construction water quality assessment program,
monitoring for compliance with WQS, and a reopener clause
authorizing the NPDES authority to reopen and modify the
permit if it is determined that the CSO controls fail to
meet WQS or protect designated uses; and
NPDES authorities should also, as noted above, commence
enforcement actions in 1993, against all CSO permittees-
which have CWA violations due to CSO discharges during dry
weather. In addition, NPDES authorities should ensure the
implementation of the nine minimum controls, noted above,
and incorporate a schedule, with appropriate milestone
dates, to implement the required long-term CSO control plan
into a civil judicial action or administrative order.
Schedules for implementation of the long-term CSO control
plan may be phased based on the relative importance of
adverse impacts upon WQS and designated uses, and on a
permittee's financial capability.
4-K Notwithstanding the permitting and enforcement provisions of
the Policy, permittees are expected to comply with any CSO-
related requirements in NPDES permits, consent decrees or court
orders which predate the Policy. ww«*w
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Comments on the draft Policy should be submitted to:
Richard Kuhlman (WH-546)
Office of Hastevater Enforcement and Compliance
US EPA
401 N Street, S.W.
Washington, D.C. 20460
If additional information is necessary, please contact
Richard Kuhlman at (202) 260-5828.
LaJuana S. Wilcher
Assistant Administrator
for Water
Sincerely yours
Herbert H. Tate, Jr.
Assistant Administrator-
for Enforcement
Enclosure
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DRAFT COMBINED SEWER OVERFLOW CONTROL POLICY
12/18/92
3 I. INTRODUCTION
* A. Purpose
* The main purposes of this Policy are to elaborate on EPA's
6 National Combined Sewer Overflow Contrpl "strategy published on
7 September 8, 1989 at 54 PR 37370 (1989 Strategy) and to expedite
8 compliance with the requirements of the Clean Water Act (CWA).
9 While implementation of the 1989 Strategy has resulted in
10 progress toward controlling combined sewer overflows (CSOs),
11 significant water quality risks remain. CSOs consist of mixtures
12 of sanitary sewage, industrial wastewater, and storm water
13 runoff. CSO discharges often contain high levels of suspended
14 solids, bacteria, heavy metals, floatables, nutrients, oxygen-
15 demanding organic compounds, oil and grease, and other
16 pollutants. CSO discharges can cause exceedances of water
17 quality standards (WQS). Such exceedances may pose risks to
18 human health, threaten aquatic life and its habitat, and impair
19 the use and enjoyment of the Nation's waterways.
20 This Policy is intended to provide guidance to permittees
21 with CSOs, National Pollutant Discharge Elimination System
22 (NPDES) permitting authorities, state water quality standards
23 authorities and enforcement authorities, in order to coordinate
24 the planning, selection, sizing and construction of CSO controls
1
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1 to meet the requirements of the CWA and to involve the public
2 fully during the decision making process.
3 This Policy reiterates the objectives of the 1989 Strategy:
4 1. To ensure that if CSO discharges occur, they are only as
5 .a result of vet weather;
f
« 2; To bring all vet weather CSO discharge points into
7 compliance vith the requirements of the CWA; and
8 3. To minimize water quality, aquatic biota, and human
9 health impacts from vet weather overflows.
10 This Policy is being issued in support of EPA's regulations
ll and policy initiatives. This document is Agency guidance only.
12 it does not establish or affect legal rights or obligations. It
13 does not establish a binding norm and is not finally
14 determinative of the issues addressed. Agency decisions in any
15 particular case vill be made by applying the lav and regulations
16 on the basis of specific facts vhen permits are issued.
17 B. Application of Policy
1« The permitting provisions of this Policy apply to all
1* combined sever systems that overflov as a result of storm vater
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1 flow, including, snow melt runoff (40 CFR Section 122.26(b) (13)).
2 CSO discharges during dry weather are prohibited by the CWA.
3 Accordingly, the permitting provisions of this Policy do not
4 * apply to discharges during dry weather from combined sewer
5 systems. Dry weather flow is the flow in a combined sewer that
6 results solely from domestic sewage, groundwater infiltration and
7 industrial wastes. In addition to the permitting provisions, the
8 Enforcement and Compliance section of this Policy describes an
9 enforcement initiative being developed for overflows that occur
10 during dry weather.
11 Consistent with the 1989 Strategy, all 30 States that need
12 CSO permitting strategies have received EPA approval or, in the
13 case of two states, conditional approval of their strategies.
14 States and EPA Regional Offices should review the State
15 strategies and negotiate appropriate revisions to them to
16 implement this Policy.
17 c. Effect on current cso control Efforts
18 Portions of this Policy may already have been addressed by
19 permittees' previous efforts to control CSOs. Therefore,
20 portions of this Policy may not apply, as determined on a case by
21 case basis, under the following circumstances:
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1 1. When this Policy is issued, any permittee which has
2 completed or substantially completed construction of CSO
3 control facilities that are -designed to meet HQS and protect
4 designated uses, and where it has been determined that water
5 quality standards are being or will be attained, is not
6 covered by the initial planning and construction provisions
7 in this Policy; however, the operation and maintenance and
'•£»''—.'• "~
8 monitoring provisions -continue to apply, if,' after
• monitoring, it is determined that WQS are not being
10 attained, the permittee should be required to submit a
11 revised CSO control plan that once implemented, will attain
12 WQS.
13 2... When this Policy is issued, any permittee which has
14 substantially developed or is implementing a CSO control
15 program pursuant to an existing permit or enforcement order,
1C and such program is considered by the NPDES permitting
17 authority to be adequate to meet WQS and protect designated
18 uses and is reasonably equivalent to the treatment
19 objectives of this Policy, should complete those facilities
20 without further planning activities otherwise expected by
21 this Policy. Such programs, however, should be reviewed and
22 modified to be consistent with the sensitive area and
23 financial capability provisions of this Policy; the
24 permittee should be subject to an enforceable, fixed-date
25 compliance schedule and should be required to develop and
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1 implement a post construction water quality monitoring
2 program; and its permit should contain reopener provisions
3 as discussed in this Policy.'
4 3. When this Policy is issued, any permittee which has
5 previously constructed CSO facilities in an effort to comply
6 with WQS but has failed to meet such applicable'standards or
" « C" " ' —• » "~
7 to protect designated uses due to remaining CSO discharges
8 may receive consideration for such efforts in future
9 enforceable orders -for long-term CSO control planning,
10 design and implementation.
11 D. small 8yst«m Considerations
12 The scope of the long-term CSO control plan, including the
13 characterization,-monitoring and modeling, and evaluation of
14 alternatives portions of this Policy may be difficult for small
15 combined sewer systems. Jurisdictions responsible for combined
16 sewer systems serving populations under 75,000 may not need to
17 complete each of the formal steps outlined in this Policy, but
18 should be required through their permits to comply with the nine
19 minimum controls, sensitive areas and public participation
20 portions of this Policy. In addition, they may propose to
21 implement any of the criteria contained in this Policy for
22 evaluation of alternative controls. Following approval of the
23 proposed project, such jurisdictions should construct the control
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1 projects and -propose a cost-effective monitoring program
2 sufficient to determine whether WQS are attained and designated
3 uses are protected. States should consider providing assistance
4 ' with monitoring in communities where the average per capita
5 income is 90 percent or less of the per capita income in the
6 State.
7 In developing long-term CSO control plans based on the above
8 small system considerations discussed in the preceding paragraph,
9 permittees are encouraged to discuss the scope of their long-term
10 CSO control plan with the WQS authority and the NPDES authority
11 to ensure that the plan includes sufficient information to enable
12 the permitting authority to identify the appropriate CSO
13 controls.
l* B. Implementation Responsibilities
15 NPDES authorities (authorized States or EPA Regional
l« Offices, as appropriate) are responsible for implementing this
17 Policy. It is .their responsibility to assure that CSO permittees
18 develop long-term CSO control plans and that NPDES permits meet
19 the requirements of the CWA. Further, they are responsible for
20 coordinating the review of the long-term CSO control plan and the
21 development of the permit with the WQS authority to determine if
22 revisions to the WQS are appropriate, In addition, they should
23 determine the appropriate vehicle (i.e., permit reissuance,
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1 information request under CWA section 308 or enforcement action)
2 to ensure that compliance with the CWA is achieved as soon as
3 practicable.
4 Permittees are responsible for documenting the
5 . implementation of the nine minimum controls and developing and
6 implementing a long-term CSp control plan, as described in this
7 "policy. EPA recognizes that financial considerations are a
8 major factor affecting the implementation of CSO controls. For
9 that reason, this Policy allows consideration of a permittee's
10 financial capability in connection with the long-term CSO control
11 planning effort, WQS review, and negotiation of enforceable
12 orders. However, each permittee is ultimately responsible for
13 aggressively pursuing financial arrangements for the
14 implementation of its long-term CSO control plan. As part of
15 this effort, communities should apply to their State Revolving
16 Fund program, as appropriate, for financial assistance.
17 EPA and the States will undertake to assure that all
18 permittees with combined sewer systems are subject to a
19 consistent review in the permit development process, have permit
20 requirements that will achieve compliance with the CWA, and have
21 compliance schedules that require the earliest practicable
22 compliance date considering physical and financial feasibility.
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1 F. Policy Development
2 This Policy devotes a separate section to each aspect
3 involved in developing or implementing CSO controls. This is not
4 to imply that each function occurs separately. Rather, the
5 entire process surrounding CSO controls, community planning, WQS
6 and permit development/revision, enforcement/compliance actions
7 and public, participation-must be coordinated to control csos
8 effectively.
9 m developing this Policy, EPA has included information on
10 what responsible parties are expected to accomplish. Subsequent
11 documents are under development that will provide additional
12 guidance on how the objectives of this Policy should be met.
13 These documents will provide guidance on: CSO permit writing;
14 definitions of the nine minimum controls; long-term CSO control
15 plans; financial capability; combined sewer system and receiving
r
16 water monitoring and modeling; and application of WQS to CSO
17 impacted waters. For most CSO control efforts however,
18 sufficient detail has been included in this Policy to begin
19 immediate implementation of its provisions.
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1 II- **» OBJICTlVn KB NMimns
2 A. Ovarvlmr
3 PMBltte.. with oort.inrt ..war ,y.t«, that have cso. rtould
« 1-wdi.t.ly
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1 5. prohibition of CSO discharges during dry weather;
2 6. control of solid and floatable materials in CSO
3 discharges;
4 7. pollution prevention programs that focus on contaminant
5 reduction activities;
6 8. public notification to ensure that the public receives
7 adequate notification of. CSO occurrences and CSO impacts;
8 and
* 9. monitoring to effectively characterize CSO impacts and
10 the efficacy of .CSO controls.
11 Attachment 1 provides examples of specific measures that may
12 be implemented by permittees to achieve each of the nine minimum
13 controls. Selection and implementation of actual control
14 measures should be based, however, on consideration of the
3.5 specific combined sewer system's characteristics discussed under
16 the sewer system characterization and monitoring portions of this
-17 Policy. Documentation of the nine minimum controls may include
18 operation and maintenance plans, revised sewer use ordinances for
1» industrial users, sewer system inspection reports,
20 infiltration/inflow studies, pollution prevention programs,
*l public notification plans, and facility plans for maximizing the
10
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1 capacities of the existing collection and treatment systems, as
2 well as contracts and schedules for minor construction programs
3 for improving the existing system's operation. The permittee
4 • should also submit any information or data on the degree to which
5 the nine minimum controls achieve compliance with water .quality
6 standards. These data and information should include results
7 made available through monitoring and modeling activities done in
a conjunction with the long-term CSO control plan described in this
9 Policy.
.10 This documentation should be submitted as soon as
11 practicable, but no later than two years after the requirement to
12 submit such documentation in an NPDES permit or enforceable
13 mechanism. Implementation of the .nine minimum controls should be
14 completed as soon as practicable but no later than the dates
15 established in the Enforcement and Compliance section of this
16 Policy. These dates should be included in an appropriate
17 enforceable mechanism.
18 Because the CWA requires immediate compliance with
19 technology-based controls (Section 301 (b)), which on a Best
20 Professional Judgement basis should include the nine minimum
21 controls, a compliance schedule for implementing the nine minimum
22 controls, if necessary, should be included in an enforceable
23 mechanism.
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1 C. . Long-Term cso control Plan
2 Permittees with CSOs are responsible for developing a long-
3 term CSO control plan that will ultimately result in compliance
4 with the requirements of the Clean Water Act. Permittees will be
5 expected to evaluate a range of control options/strategies and to
« coordinate the development of the long-term CSQ. control pl*n and
7 its subsequent implementation with the NPDES authority and the
8 state authority responsible for reviewing and revising the
9 State's WQS. The selected controls should be designed to allow
10 cost effective expansion or cost effective retrofitting if
11 additional controls are determined to be necessary to meet WQS or
12 to protect designated uses.
13 This policy identifies EPA's major objectives for the long-
14 term CSO control plan. Permittees should develop this long-term
15 CSO control plan as soon as practicable, but generally within two
16 years after the effective date of the permit provision, Section
17 308 information request, or enforcement action requiring the
18 permittee to develop the plan. NPDES authorities may establish a
19 longer timetable for completion of the long-term CSO control plan
20 on a. case-by-case basis to account for site specific factors
21 which may influence the complexity of the planning process. Once
22 agreed upon, these dates should be included in the community's
23 NPDES permit or in an appropriate enforcement mechanism.
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1 EPA expects each long-term CSO control plan to utilize
2 appropriate information to address the following minimum
3 elements. It should also include both fixed-date project
4 implementation schedules (which may be phased) and a finance plan
5 to design and construct the project as soon as practicable. The
minimum elements of the long-term CSO control plan are described
6
7 below.
• 1. Characterization, Monitoring, and Modeling of the
9 Combined Sewer System
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11
12
13
14
15
16
17
18
19
20
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In order to design a CSO control plan adequate to meet the
requirements of the CWA, a permittee should have a thorough
understanding of its combined sewer system, the response of
the system to various rain events, the characteristics of
the overflows, and the water quality impacts that result
from the CSO discharges. The permittee should adequately
characterize through monitoring, modeling, and other means
as appropriate, for a range of storm events, the response of
its combined sewer system to wet weather events including
the number, location and frequency of CSOs, and the impacts
of the CSOs and other pollution sources on the receiving
21 waters and their designated uses.
The purpose of the system characterization, monitoring and
modeling program initially is to assist the permittee in
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1 developing appropriate measures to implement the nine
2 minimum controls and, if necessary, to support development
3 of the long-term CSO control plan. The monitoring and
4 modeling data also will be used to evaluate the expected
5 effectiveness of both the nine minimum controls and, if
« necessary, the long-term CSO controls, to meet WQS.
7 The major elements of a sever system characterization are
• described below.
» a. Rainfall Records - The permittee should examine
10 **• complete rainfall record for the geographic area of
11 its existing combined «ewer system using sound
12 statistical procedures and best available data. The
13 permittee should evaluate flow variations in the
14 receiving water body to^correlate between CSOs and
15 receiving water conditions.
16 b- Combined Sewer System Characterization - The
17 permittee should evaluate the nature and extent of its
18 combined sewer system through evaluation of available
19 8ewer system records, field inspections and other
20 activities necessary to understand the number, location
21 and frequency of overflows and their location relative
22 to sensitive areas and up-stream pollution sources.
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1 c. CSO Monitoring - The permittee should develop a
2 comprehensive, representative monitoring program that
3 measures the frequency; duration, volume and pollutant
4 concentration of CSO discharges and assesses the impact
5 of the csos on the receiving waters. The monitoring
6 program should include necessary CSO effluent and
7 ambient in-stream monitoring and, where'appropriate,
" • £•• " •—• • ~~
8 other monitoring protocols such as biological
9 assessment, toxicity testing and sediment sampling.
10 Monitoring parameters should include, for example,
" oxygen demanding pollutants, nutrients, toxic
12 pollutants, sediment contaminants, bacteriological
13 indicators, and toxicity. A representative sample of
14 overflow points can be selected that is sufficient to
15 allow characterization of CSO discharges and their
16 water quality impacts and to facilitate evaluation of
17 control plan alternatives. Permittees should take
18 appropriate precautions to ensure the safety of staff
19 when monitoring CSOs during storm events including the
20 use of mechanized monitoring equipment.
21 d- Modeling - Modeling of a combined sewer system is
22 recognized as a valuable tool for predicting sewer
23 system response to various storm events and assessing
24 water quality impacts when evaluating different control
25 strategies and alternatives. EPA supports the proper
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l and effective use of models, where appropriate, in the
2 evaluation of the nine minimum controls and the
3 development of the long-term CSO control plan, it is
« also recognized that there are many models which may be
5 used to da this. These models range from the simple to
< the complex. Having decided to use a model, the
* permittee should base its choice of a, model on the
8 characteristics of its combined sewer system, the
9 number and location of overflow points, and the
10 sensitivity of the receiving water body to the CSO
11 discharges. The sophistication of the model should
12 relate to the complexity of the system to be modeled.
13 EPA c*P«cts that continuous simulation models, using
14 historical rainfall data,, may be the best way to model
15 cs? systems and their impacts. Because of the
16 iterative nature of modeling CSO systems and their
17 impacts, monitoring and modeling efforts are
18 complementary and should be coordinated.
19 2- Consideration of Sensitive Areas
« EPA expects a permittee's long-term CSO control plan to give
21 the highest priority to controlling overflows to sensitive
22 areas, including designated Outstanding National Resource
23 Haters, National Marine Sanctuaries, waters with threatened
24 and endangered species and their habitat, waters with
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1 contact recreation, public drinking water intakes or their
2 designated protection areas, and shellfish beds. For such
3 areas, the long-term CSO control plan should:
4 a. prohibit new or significantly increased overflows;
5 b. i. eliminate or relocate overflows that discharge
'€ to sensitive areas wherever physically and
7 economically achievable, except where elimination
8 or relocation would provide less environmental
9 protection than additional treatment; or
10 ii. where elimination or relocation is not
11 physically and economically achievable, or would
12 provide less environmental protection than
13 additional treatment, provide the level of
14 treatment for remaining overflows deemed necessary
IS to meet WQS for full protection of existing and
l< designated uses. In any event the control shall
17 not be less than those described in Evaluation of
18 Alternatives below; and
19 c. Where elimination or relocation has been proven
20 not to be physically possible or economically
21 achievable, permitting authorities should require, for
22 each subsequent permit term, a reassessment based on
17
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1 new or improved technologies to eliminate or relocate,
2 or on changed circumstances that influence economic
3 achievability.
4 3. Evaluation of Alternatives
5 EPA expects the long-term CSO control plan to consider a
6 reasonable range of alternatives. The plan should, for
7 example, evaluate controls that would be necessary to
8 achieve an average of zero overflows per year, one to three,
9 four to seven, and eight to twelve overflows per year.
10 Because the final long-term CSO control plan will become the
11 basis for NPDES permit limits and requirements, the selected
12 controls should be sufficient to meet CWA requirements.
13 In addition to considering sensitive areas, the long-term
** cso control plan should adopt one of the following
15 approaches:
1C a. "Presumption" Approach
17 A program that meets any of the criteria listed below
18 would be presumed to provide an adequate level of control to
l» meet CWA requirements, provided the permitting authority
20 determines that such presumption is reasonable in light of
21 the data and analysis conducted in the characterization,
18
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1 monitoring, and modeling of the system and the consideration
2 of sensitive areas described above. However, this
3 presumption will not apply if the permitting authority
4 determines that the long-term CSO control plan will not
5 result in attainment of CWA. requirements.
'. i. no more than an average of four overflow events per
7 year for urban areas, provided that the permitting
8 authority may allow up to two additional overflow
9 events per year; and no more than an average of five
10 overflow events per year for rural areas, provided that
11 the permitting authority may allow up to two additional
12 overflow events per year. For the purpose of this
13 criterion, an overflow is the discharge of combined
14 sewage that does not receive the minimum treatment
15 specified below and an overflow event is one or more
16 overflows from a combined sewer system as the result of
17 a single rain event; or
18 ii- the elimination or the capture for treatment of no
19 less than 85% by volume of the combined sewage
20 collected in the combined sewer system during rainfall
21 events on a system-wide annual average basis; or
22 iii* the elimination or reduction of no less than the
23 mass of the pollutants identified as causing water
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1
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3
4
5
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7
8
9
10
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12
17
18
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quality impairment through the sever system
characterization, monitoring, and modeling effort for
the volumes which would be eliminated or captured for
treatment under paragraph ii. above.
These criteria are provided because data and modeling
of wet weather events often do not give a clear picture of
the level, of cs* controls,necessary to protect WQS. m the
absence of such certainty, that permittees should develop
programs to meet at least one of these criteria because
aggregate national data suggest that the incremental
pollution control benefits at this level of control are
substantial compared to incremental costs for most cso
13 systems.
flows resulting from
15 events, except those in excess of the
16 ahrt_ 8hould receivc a nininuiB of.
rr-atMnt for r««,v.l o, tto.tM.1..
•olid. ^uiv.l«,t to that aohi.v^ by prila(lry
claritioation a. d-crib* !„ «,. .^^ ot
Municipal w..t.w.t.r Tr.ata.nt Plant., pr.^^,
— publi*«, ^ «,. w.t«: Environs Fed«r.tion,
22
^^^* •^••S' -^mmm^* ^ ^&^^K L_«V n • ^M^f fm V tfMO^^at^ ^ ^ — ^»
> i ana
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1
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4
6
7
8
9
10
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12
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disinfection of effluent, if necessary to meet
WQS, protect designated uses and protect human
health, including removal of harmful disinfection
chemical residuals where necessary.
b. "Demonstration** Approach
A permittee may demonstrate that a selected control
program, though not meeting the criteria specified in
H.C.a.a. above is adequate to meet CWA requirements.
To be a successful demonstration, the permittee should
demonstrate each of the following:
i. the controls are clearly adequate to meet WQS
and protect designated uses, unless WQS or uses
cannot be met as a result of natural background
conditions or pollution sources other than cso
15 discharges;
ii. the cso discharges remaining after
implementation of the proposed control program
will not cause or contribute to the contravention
of WQS or the receiving waters' designated uses,
where WQS or designated uses are not met in part
because of natural background conditions or
pollution sources other than CSO discharges, using
21
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l a wasteload allocation or other means of
2 apportioning pollutant loads; and
3 iii. the selected controls will provide the
4 maximum pollution reduction benefits reasonably
5 attainable; and
* iv. the selected control program is designed to
7 allow cost effective expansion or cost effective
• retrofitting if additional controls are determined
9 to be necessary to meet WQS or designated uses.
10 4. Cost/Performance Considerations
11 T*1® permittee should develop appropriate cost/performance
12 curves to demonstrate the relationships among a
13 comprehensive set of reasonable control alternatives that
14 correspond to the different overflow ranges specified in
15 Section II. C. 3. This should include an analysis to
16 determine where the increment of pollution reduction
17 achieved in the receiving water diminishes compared to the
18 increased costs. These analyses, often known as knee of
1» the curve, should be used to help guide selection of
20 controls.
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1 5. . Operational Plan
2 After agreement between the-permittee and NPDES authority on
3 the necessary CSO controls to be implemented under the long-
4 term cso control plan, the permittee should revise the
5 operation and maintenance program developed as part of the
6 nine minimum controls to include the agreed upon long-term
7 CSO controls. The revised operation and maintenance program
8 should maximize the removal of pollutants during and after
» each rain event using aU available facilities within the
10 collection and treatment system.
11 6. Maximizing Treatment at the POTW Treatment Plant
12 In some communities, POTW treatment plants may have primary
13 treatment capacity in excess of its secondary treatment
14 capacity. One effective strategy to abate pollution
15 resulting from CSOs is to maximize the delivery of flows to
16 the POTW treatment plant for treatment. Delivering these
17 flows can have two significant water quality benefits:
18 first, increased flows to the POTW treatment plant may
19 enable the permittee to eliminate or minimize overflows to
20 sensitive areas; second, by reaching the POTW treatment
21 plant, combined sewer flows will receive at least primary
22 treatment prior to discharge.
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1 If there is support in «« permit record
2 Fecnil vaniAM^a j— •«<%
3 below, the permitting authority may grant the
* generic bypass
« ^» ^»^»^»
(
would define in the permit the
6
7 granted, the
«- ~" -«*w»»x« axso provide that it
A ' ^* ^^
A
character of pollutants being introduced to the POTW. The
10 «o 4- bypass
,, — •—-.-M.I. snouxa also make it
clear that all wet weather flows passina
*«WB passing
*• frliA Tl/vnu A. ^
plant
__ -- ———- primary
« cl^ifioatio,,, solid. ^ 0..^,^
« ^
• •
Section Il.c.a.a. and any other
16 ^, .,_ ^ provlded<
• O fir fAAIH^ -f-mm •
«*wOCUiiB trOni AltV w^v^^ 4 «%«& ' ^
i* ° * treatnent facility, includino
• V fi A/.;
*Aow8 or portions
" from portions of the treatment system
22
23 with non-divey*A4 fiowf. _„. . ^,
riows prior to discharge,
24
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1 EPA interprets its bypass regulation, at 40 CFR Section
2 122.41(m)(4), to allow a permit to authorize a generic
3 bypass of the secondary treatment portion of the POTW
4 treatment plant for combined sever flows in certain limited
5 circumstances. .This provision would apply only to those
6 situations where the POTW would ordinarily qualify for
7 bypass approval on a case-by-case basis. Therefore, there
8 must be sufficient data in the administrative- record -
* (reflected in the permit fact sheet or statement of basis)
10 supporting all the requirements in Section 122.41 (m) (4) for
\ • ,\. -
11 approval of an anticipated bypass. Under the regulation,
12 data must show that the bypass was unavoidable to prevent
13 loss o* life, personal injury or severe property damage;
14 that there was no feasible alternative to the bypass; and
IS that the permittee submitted the required notices. In
16 addition, the regulation provides that a bypass may be
17 approved only after consideration of adverse effects.
18 For the purposes of applying this regulation to CSO
l» permittees, "severe property damage" could include
20 situations where flows above a certain level wash out the
21 POTW's secondary treatment system. EPA further believes
22 that the feasible alternatives requirement of the regulation
23 can be met if the record shows that the secondary treatment
24 system is properly operated and maintained, that the system
25 has been designed to meet secondary limits for flows greater
25
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1 than the average dry weather flow, and that it would not be
2 feasible to operate the secondary treatment system to
3 accommodate the higher wet weather flows. The feasible
4 alternative analysis should include, for example,
5 consideration of advanced chemical primary treatment and
6 non-biological secondary treatment. Other bases supporting
7 a finding of no feasible alternative may also be available
8 on a )case-by-case basis. As part of its consideration of
» possible adverse* effects resulting from the bypass, the
10 permitting authority should also'ensure that the bypass will
11 not cause exceedances of WQS.
12 7. Implementation Schedule
13 The permittee should include all pertinent information
14 necessary to develop the construction and finance schedule
15 for implementation of CSO controls. Schedules for
16 implementation of the CSO controls may be phased based on
17 the relative importance of adverse impacts upon WQS and
18 designated uses and on a permittee's financial capability.
19 Construction phasing should consider:
20 *• Eliminating overflows that discharge to sensitive
21 areas as the highest priority;
26
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1 b. Use impairment;
2 c. Permittees financial capability including
3 consideration of such factors as:
4 i. .Median household income/total project cost per
5 household;
« ii. Per capita debt as a percent of full market
7 property value;
• iii. Property tax revenues as a percent of full
• market property value;
10 iv. Property tax collection rate;
11 v. Unemployment;
12 vi. Bond rating;
13 vii. Grant and loan availability;
14 viii. Residential, commercial and industrial user
15 fees; and
27
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1 ix. Other viable funding mechanisms and sources
2 of financing.
3 8. Post-Construction Compliance Monitoring Program
4 The selected CSO controls should include a post-
5 construction water quality monitoring program adequate to
6 verify compliance with water quality standards and
• i
7 protection of designated uses. This water quality
8 compliance monitoring program should include a plan to be
» approved by the NPDES authority that details the monitoring
•
10 protocols to be followed/ including the necessary effluent
11 and ambient monitoring and, where appropriate, other
12 monitoring protocols such as biological assessments, whole
13 effluent toxicity testing, and sediment sampling.
14 9. Public Participation
15 EPA expects that the permittee, in developing its long-term
16 CSO control plan, will employ a public participation process
17 that actively involves the affected public in the decision-
18 making to select the long-term CSO controls. The affected
l* public, includes rate payers, industrial users of the sewer
20 system, persons down-stream from the CSO discharges, and any
21 other interested persons.
28
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1 ZZZ. COORDINATION WITH STATE WATER QUALITY STANDARDS
2 A. Overview
3 Water quality standards are State adopted, or Federally
4 promulgated rules which serve as the goals for the water body and
5 the legal basis for the water quality-based NPDES permit
« requirements under the CWA.j^ Long-tern CSO control plans «ire
" " i
7 developed to reduce risk to human health and the environment by
8 restoring and protecting the designated uses and quality of the
• affected waters.
10 State WQS authorities, NPDES authorities, EPA regional
11 offices and permittees should meet early and frequently
12 throughout the long-term CSO control planning process to
13 coordinate the development of the long-term plan with the review
14 and possible revision of WQS and implementation procedures on
15 CSO-impacted waters. As part of these meetings, participants
16 should agree on the data, information and analyses needed to
17 support the development of the long-term CSO control plan and the
18 review of applicable WQS, if appropriate. Agreements should be
19 reached on the monitoring protocols and models that will be used
20 to evaluate the water quality impacts of the overflows, to
21 analyze the attainability of the WQS and to determine the water
22 quality-based requirements for the permit. Many opportunities
23 exist for permittees and States to share information as control
24 programs are developed and as WQS are reviewed. Such information
-------
1 should assist States in determining the need for revisions to WQS
2 and implementation procedures to better reflect wet weather
3 events. Coordinating the development of the long-term CSO
4 control plan and the review of the WQS enables the NPDES
5 authority to develop a permit that complies with WQS consistent
« with Sections 301(b)(l)(C) and 402(a)(2) of the CWA.
7 EPA encourages States and permittees to sponsor workshops to
* i
8 involve the affected public in the development of the long-term
» CSO control plan and in the review and potential revision of the
10 WQS on CSO-impacted waters. Workshops provide a forum for
11 including the public in discussions of tihe implications of the
12 proposed long-term CSO control plan on the water quality and uses
13 for the receiving water.
1* B. WQS Reviews
15 Agency regulations and guidance provide States with the
1« flexibility to adapt their WQS and implementation procedures to
17 reflect wet weather events. For example, a State may adopt site-
18 specific criteria for a particular pollutant if the State
19 determines that the site-specific criteria still protects the
20 designated use (40 CPR Section 131.11). in addition, the
21 regulations at 40 CFR Section 131.lO(g), (h), and (j) specify
22 when and how a designated use may be modified. For example; a
23 State may remove a designated use from their water quality
24 standards if the designated use is not an existing use. An
30
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1 existing use is a use actually attained in the water body on or
2 after November 28, 1975. A State also nay not remove a
3 designated use that will be attained by implementing the
1 4 technology-based effluent limits required under Sections 301(b)
5 and 306 of the CWA and by implementing cost-effective and
€ reasonable best management practices for nonpoint source
7 controls. Thus, if a State had reason to believe that the
a current designated use could be protected after implementation of
9 the technology-based controls of the CWA, then the use could not
10 be removed.
11 In reviewing the applicability of their WQS and
12 implementation procedures to CSO-impacted waters, States could
13 define more explicitly their recreational and aquatic life uses
14 and then revise the criteria accordingly to protect the revised
15 uses. For example, a State may be able to designate boating
16 rather than swimming as a use, if swimming is not an existing
17 use; thereby justifying a less stringent bacteriological
18 criterion. Another option is for States to adopt partial uses by
19 defining when swimming does not exist, such as during certain
20 seasons of the year or during a particular type of storm event.
21 In making such adjustments to their uses, States must ensure that
22 downstream uses are protected, and that during other seasons or
23 after the storm event has passed the use is fully protected.
24 In addition to defining recreational uses with greater
25 specificity, States can also define more precisely the aquatic
31
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1 uses to be
2 be protected nay assist
3 ". citiz«» for . ^^ plan. Por .xa^.1., „«« than^
* defining the use as aouatie
^ ^«* «**£«MB W A W
S - input from the permittee and
€ as »
21
22
23
* *»Aue gill, crappy
and large mouth bass or a limited warm water
carp. «„ st.t.-»y
8.
10 levels to reflect the
11
12
13 wra ™ ^ por ^p^ states
14
.„ ^
15 h^.. — ^ ^, - . • . * spawning
CSOs
or if
1« or the toxicity of the
» the acute or chronic physiological stress on orMoaM^tl
18 potential of aquatic organisms.
» XV. EXPECTATIONS FOR PBRIHTTIHO AUTHORITIES
20 A. overview
CSO. ar. point .ourc.. subj^t to
both fchnolooy-b.^ and v.t«
of the CWA. CSOs are not subject to secondary
24 treats* regulations
32
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1 works (Montgomery Environmental Coalition vs. goati«>. 646 F.2d
2 568 (D.C. Cir. 1980)).
3 All permits for CSO discharges should require the nine
•
4 minimum controls as a minimum best available technology
5 economically achievable and best conventional technology
6 (BAT/BCT) established on a best professional judgment (BPJ) basis
7 .(40 CFR Section 125.3). Water quality-based requirements are to
8 be established based on applicable water quality standards.
• This policy establishes a uniform, nationally consistent
10 approach to developing and issuing NPDES permits .to permittees
11 with CSOs. Permits for CSOs should be developed expeditiously to
12 minimize, if not eliminate water quality impacts. A single,
13 system-wide permit generally should be issued for all discharges,
14 including CSOs, from a combined sewer system operated by a single
15 authority. When different parts of a single combined sewer
16 system are operated by more than one authority, permits issued to
17 each authority should generally require joint preparation and
18 implementation of the elements of this Policy and should
19 specifically define the responsibilities and duties of each
20 authority. Permittees should be required to coordinate system-
21 wide implementation of the nine minimum controls and the
22 development and implementation of the long-term CSO control plan.
23 The individual authorities are responsible for their own
24 discharges and should cooperate with the permittee for the POTW
25 receiving the flows from the combined sewer system. When a CSO
33
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1 is permitted separately from the POTW, both permits should be
2 cross-referenced for informational purposes.
3 Regions and States should review the CSO permitting
4 priorities established in the State CSO Permitting.strategies
5 developed in response to the 1989 Strategy. Regions and States
6 may elect to revise these previous priorities, in setting
7. permitting priorities, Regions and^States should not just focus
8 on those permittees that have initiated monitoring'programs.
9 When setting priorities, Regions and States should consider, for
10 example, the known or potential impact of CSO discharges on
11 sensitive areas, and the extent of upstream industrial user
12 dischargers to the combined sewer system.
13 During the permittee's development of the long-term CSO
14 control plan, the permit writer should promote coordination
15 between the permittee and state HQS authority in connection with
16 possible WQS revisions. Once the permittee has completed
17 development of the long-term CSO control plan and has coordinated
18 with the permitting authority the selection of the controls
19 necessary to meet the requirements of the CWA, the permit writer
20 should reissue/modify the permit to include enforceable
21 requirements for implementation of the long-term CSO control
22 plan, including conditions for water quality monitoring and
23 operation and maintenance.
34
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1 B. NFDBfl Permit Requirements
2 Following are the major elements of NPDES permits to
.3 implement this Policy and ensure protection of water quality.
4 1. Phase I permits - Requirements for Demonstration of
5 Implementation of the Mine Minimum Controls and Development
« of the Long-Term CSO Gontrol^Plan
7 In the Phase I permit issued/modified to reflect this
8 Policy, the NPDES authority should at least require
-9 permittees to:
10 &• immediately implement BAT/BCT, which at a minimum
11 includes the nine minimum controls on a BPJ basis;
12 *>• develop and submit a report documenting the
13 implementation of the nine minimum controls within two
14 years of permit issuance/modification;
15 c- immediately comply with applicable WQS expressed in
16 the form of a narrative limitation; and
17 d- develop and submit, consistent with this Policy and
18 based on a schedule in the permit, a long-term CSO
19 control plan as soon as practicable, but generally
20 within two years after the effective date of the permit
35
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1 issuance/modification. However, permitting authorities
2 may establish a longer timetable for completion of the
3 long-term CSO control plan on a case-by-case basis to
4 account for site specific factors that may influence
5 the complexity of the planning process.
6 The NPDES authority should include separate compliance dates
7 on.the fastest, practicable.schedule for each of the nine
8 minimum controls in an enforceable order issued in
9 conjunction with the Phase I permit. The use of enforceable
10 orders is necessary unless Congress amends the CWA to extend
11 the compliance dates for meeting technology-based and water
12 quality-based requirements. All orders should require
13 compliance with the nine minimum controls no later than
14 January 1, 1997.
15 2. Phase II permit - Requirements for Implementation of a
16 Long-Term CSO Control Plan
17 Once the permittee has completed development of the long-
18 term CSO control plan and the selection of the controls
l» necessary to meet CWA requirements has been coordinated with
20 the permitting and WQS setting authorities, the NPDES
21 authority should modify/reissue the Phase II permit to
22 include enforceable requirements for implementation of the
3 long-term CSO control plan. Proper implementation of the
approved long-term CSO control plan will be deemed to be
36
f:
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l compliance with the Phase II permit. The Phase II permit
2 should contain:
3 a. Requirements to implement the technology-based
4 controls determined on a BPJ basis (e.g., the nine
5 minimum controls);
C b* Narrative requirements which insure that the
- '' \ • ' • < ' - •
7 selected controls are implemented, operated and
• maintained as described in the long-term CSO control
• plan;
10 c- Water quality-based effluent limits under 40 CFR
11 Sections 122.44(d)(l) and 122.44(Jc), requiring at a
12 minimum immediate compliance with the numeric
13 performance standards for the selected controls, based
14 on average design conditions specifying at least one of
15 the following:
16 i. A maximum number of discharges per year for
17 specified design conditions; or
18 ii. A minimum percentage capture of discharges by
19 volume for specified design conditions; or
37
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1 ill. A minimum percentage reduction of the mass
2 of pollutants discharged for specified design
3 conditions;
4 d. A requirement to implement, with an established
5 schedule, the approved post construction water quality
* assessment program;
1 e. A requirement to re-assess overflows to sensitive
• areas in those cases where elimination or relocation of
9 the overflows were proven not to be physically possible
10 or economically achievable. The reassessment should be
11 based on consideration of new or improved technologies
12 to eliminate or .relocate overflows or changed
13 circumstances that influence economic achievability.
14 f• Provisions establishing generic bypass
15 requirements, as appropriate, consistent with Section
16 II.C.6. of this Policy;
17 g- A requirement to monitor to collect sufficient
18 information to evaluate compliance with WQS; and
19 h. A reopener clause authorizing the NPDES authority
20 to "open and modify the permit upon determination that
21 **• cso controls fail to meet WQS or protect designated
22 uses. Upon such determination, the NPDES authority
38
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19
20
23
24
1 should promptly notify the permit holder and proceed to
2 modify or reissue the permit to require the submittal
3 of a revised CSO control plan as soon as practicable.
4 If tfce initial CSO control plan was approved under the
5 demonstration provision of Section II.C.3.b., the
« revised plan, at a minimum, should provide for controls
1 that satisfy one of the criteria in Section II.C.3.a.
8 Unless the permittee can comply with all of the requirements
» of the Phase II permit, within the term of the Phase II
10 permit, the NPDES authority should include in an enforceable
11 order compliance dates on the fastest practicable schedule
12 for those activities directly related to meeting the
13 requirements of the CWA. For major permittees, the
14 compliance schedule should be placed in a judicial order.
15 Proper compliance with the schedule for implementing the
1« controls contained in the long-term CSO control plan
17 constitutes compliance with the Phase II permit.
18 3. Phasing Considerations
Implementation of CSO controls may be phased based on the
relative importance of and adverse impacts upon WQS and
21 designated uses, as well as the permittee's financial
22 capability and its previous efforts to control CSOs. The
NPDES authority should evaluate the proposed implementation
schedule and construction phasing discussed in Section
39
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1 II.C.7. of this Policy. The permit should require immediate
2 compliance with the controls proposed in the long-term CSO
3 control plan. If immediate compliance with the Phase II
4 permit is not possible, an enforcement order, consistent
5 with the Enforcement and Compliance Section of this Policy,
6 should be issued in conjunction with the Phase II permit
7 which specifies the schedule and milestones for
8 implementation of the long-term CSO control plan.
ENFORCEMENT AND COMPLIANCE
10 A. Overview
11 Jt is important that permittees act immediately to take the
12 necessary steps to comply with the CWA. The CSO enforcement
13 effort will commence with an initiative to address CSOs that
14 discharge during dry weather, followed by an enforcement effort
15 in conjunction with permitting CSOs discussed earlier in this
16 Policy.
17 Success of the enforcement effort will depend in large part
18 upon expeditious action by MPDES authorities in issuing
19 enforceable permits that include requirements both for the nine
20 minimum controls and compliance with all other requirements of
21 the CWA.
40
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1 As a further inducement for permittees to cooperate with .
2 this process, EPA is prepared to exercise its enforcement
3 discretion in determining whether to seek civil penalties for
4 past CSO violations if permittees meet the objectives and
5 schedules of this Policy and do not have any discharges during
€ dry weather.
1 B... Enforcement of CSO Dry Weather Discharge Prohibition
8 EPA intends to commence (during the second half of 1993) an
9 enforcement initiative against all CSO permittees which have CWA
10 violations due to CSO discharges during dry weather. Discharges
11 during dry weather have always been prohibited by the NPDES
12 program. Such discharges create serious public health and water
13 quality problems. EPA will use its CWA Section 308 monitoring,
14 reporting, and inspection authorities, together with NPDES State
15 authorities, to locate these violations, and to determine their
16 causes. Appropriate remedies and penalties will be sought for
17 CSO discharges during dry weather. EPA will provide NPDES
18 authorities more specific guidance on this enforcement initiative
19 separately.
20 C. Enforcement of Wet Weather CSO Requirements
21 Under the CWA, EPA can use several enforcement options to
22 address permittees with wet weather discharges. Those options
23 directly applicable to this Policy are Section 308 Information
41
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1 Requests, Section 309 (a) Administrative Orders, Section 309 (g)
2 Administrative Penalty Orders, Section 309 (b) and (d) Civil
3 Judicial Actions/ and Section 504 Emergency Powers. NPDES states
4 should use comparable means.
5 NPDES authorities should set priorities for enforcement
6 based on environmental impacts or sensitive areas affected by CSO
7 discharges. Permittees thatthave voluntarily initiated
8 monitoring and are progressing expeditiously toward appropriate
9 CSO controls should be given due consideration for their efforts.
10
1. Enforcement for Compliance with Phase I Permits
11 Enforcement for compliance with Phase I permits will focus
12 on requirements to implement at least the nine minimum
13 controls, and develop the long-term CSO control plan leading
14 to compliance with the requirements of the CWA. Where
15 immediate compliance with the Phase I permit is infeasible,
l« the NPDES authority should issue enforceable orders, in
17 concert with the Phase I permit, requiring compliance with
18 the CWA and imposing compliance schedules with dates for
19 each of the nine minimum controls as soon as practicable.
20 All enforcement authorities should require compliance with
21 the nine minimum controls no later than January l, 1997.
22 Where the NPDES authority is issuing an order with a
^
23 compliance schedule for the nine minimum controls, this
24 order should also include a schedule for development of the
42
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1 long-tern CSO control plan.
2 If a CSO permittee fails to meet the final compliance date
*
3 of the enforceable order, the NPDES authority should
4 initiate appropriate judicial action.
5 2. Enforcement for Compliance with Phase XI Permits
6 The main focus for enforcing compliance with Phase II
7 permits will be to incorporate the long-term CSO control
8 plan through a civil judicial action or an administrative
• order requiring compliance with the CWA and imposing a
10 compliance schedule with appropriate milestone dates
11 necessary to implement the plan. Priority for enforcement
12 actions should be set based on environmental impacts or
13 sensitive areas affected by CSO discharges.
14
15 In general, a judicial order is the appropriate mechanism
16 for incorporating the above provisions. Administrative
17 orders, however, may be appropriate for permittees whose
IB long-term control plans will take less than five years to
19 complete, and for minors that have complied with the final
20 date of the enforceable order for compliance with their
21 Phase I permit. If necessary, any of the nine minimum
22 controls that have not been implemented by this time should
23 be included in the terms of the judicial order.
43
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1 D. Penalties
2 EPA is prepared not to seek civil penalties for past CSO
3 violations, if permittees have no discharges during dry weather
4 and meet the objectives and schedules of this Policy.
5 Notwithstanding this, where a permittee has other significant CWA
6 violations for which EPA or the State is talcing judicial action,
7 penalties may be considered as part of that action for the
8 following:
9 1. cso discharges during dry weather;
10 2- Violations of CSO-related requirements in NPDES permits,
11 consent decrees or court orders which predate this policy;
12 or
13 3. Other CWA violations.
14 EPA will not seek penalties for past CSO violations from
15 permittees that fully comply with the enforceable order requiring
16 compliance with the Phase I permit. For permittees that fail to
17 comply with the above enforceable order, EPA will exercise its
18 enforcement discretion in determining whether to seek penalties
l» for the time period for which the compliance schedule was
20 violated. if the milestone dates of the enforceable schedule
21 are not achieved and penalties are sought, penalties should be
22 calculated from the last milestone date that was met.
44
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1 At the tine of the judicial settlement imposing a-compliance
2 schedule implementing the Phase II permit requirements, EPA will
3 not seek penalties for past CSO violations from permittees that
4 fully comply with the enforceable order requiring compliance with
5 the Phase I permit and if the terms of the judicial order are
6 expeditiously agreed to on consent. However, stipulated
7 penalties for violation of the judicial order generally should be
8 included in the order, consistent with existing X^enby policies.
9 Additional guidance on stipulated penalties concerning long-term
10 CSO controls and attainment of WQS will be issued.
45
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Attachment 1
2
3
4
COMBINED SEWER OVERFLOWS
EXAMPLES OF ACTIVITIES TO MEET THE NINE
MINIMUM CONTROLS
5
6.
7
8
9
10
11
12
i. Proper O&M
o Develop procedures to ensure routine
inspection and maintenance of the
collection system and CSO structures
o Allocate earmarked funds for O&M
o Provide training programs for the
inspection and maintenance staff
o Develop a documentation program for O&M
activities
13
14
15
16
17
18
19
20
2. Maximize
Collection
System
Storage
o
o
Develop a program to limit industrial
and commercial discharges during vet
weather periods
Initiate a program to disconnect roof
leaders
Install inflatable dams
Install a computer controlled flow
routing system
21
22
23
24
3. Pretreatment
Program
Review
Identify and evaluate industrial user
discharges up-stream of all CSOs
Enact local sewer use ordinances or
revise individual control mechanisms to
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1
2
3
4
5
6
7
a
9
10
11
12
13
14
15
1C
17
18
19
20
21
22
23
24
O
4 . Maximize o
Flow to POTW
o
5. Dry Weather o
Overflow
Prohibition
0
6 . Floatables o
Control
o
7 . Pollution o
Prevention o
0
control industrial discharges during
vet weather as appropriate
Review CSO monitoring results to
identify and eliminate industrial
pollutants discharged from CSOs
Evaluate possible modifications to
existing POTW to increase treatment
capacity during wet weather
Evaluate use of abandoned units during
wet weather periods
Develop an inspection program to
identify dry weather overflow locations
and causes
Develop and implement a plan to
immediately eliminate all DWOs
o Install bar screens and booms at CSO
outfalls
o Use skimmer boats to collect floatables
in the receiving water
Institute a public education program
Promote water conservation
Institute contaminant control programs
such as regular street cleaning, anti-
litter campaign, recycle program, and
47
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product bans
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
8. Public o
Notification
9. Monitoring
Announce use restrictions on TV and
radio.
Initiate a public information system
where all major CSO issues are
identified, possible solutions and
associated costs are explained.
Post notices at affected areas.
Maintain records of overflow
occurrences and impacts
Monitor and report overflow
characteristics
Monitor and report water quality impacts
from CSOs to the receiving waters
Monitor and report beach and shellfish
bed closures and swimming restrictions
due to CSOs
48
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