The TMDL Process Guidance for Water Quality-Based Decisions: the TMDL Process

United States Office of Water EPA 440/4-91-001 Environmental Protection (WH-553) April 1991 Agency Washington, D.C. 20460

EPA Guidancefor Water Quality-based Decisions: The TMDL Process Guidance for Water Quality-based Decisions: The TMDL Process

Assessment and Watershed Protection Division U.S. Environmental Protection Agency Washington, D.C. 20460 This document provides guidance only. It does not establish or affect legal rights or obligations. This guidance may be reviewed and revised periodically to reflect changes in EPA’s strategy for the implementation of water quality-based controls, to include new information, or to clarify and update the text. Decisions in any particular case will be made by applying the Clean Water Act and implementing regulations. Comments are invited and will be considered in future revisions. Comments or inquiries should be directed to : Watershed Branch Assessment and WatershedProtection Division (WH-553) U. S. Environmental Protection Agency Washington, D.C. 20460 FOREWORD

This document, “Guidance for the Implementation of Water Quality-based Decisions: The TMDL Process,” is intended to define and clarify the requirements under section 303(d) of the Clean Water Act. Its purpose is to help State water quality program managers understand the application of total maximum daily loads within the water quality-based approach to establish pollution control limits for waters not meeting water quality standards.

Water quality management has become increasingly more complicated. Problems such as toxic contaminants, sediments, nutrients, and habitat alteration result from a variety of point and nonpoint sources. The TMDL process is established under the Clean Water Act as the mechanism to address these problems in a comprehensive manner in situations where technology-based controls are not adequate.

Through this guidance we hope to reduce the uncertainties associated with TMDLs and to establish the TMDL process as an effective water quality management tool for both point and nonpoint source pollution control.

Martha G. Prothro, Director Office of Water Regulations and Standards US Environmental Protection Agency Washington, D.C. TABLE OF CONTENTS

Page

CHAPTER 1 - INTRODUCTION ...... 1 Purpose and Summary ...... 1 Policies and Principles ...... 2 Clean Water Act Section 303(d) ...... 4 Water Quality Planning and Management Regulation ...... 6 CHAPTER 2 - THE WATER QUALITY-BASED APPROACH ‘l-0 POLLUTION CONTROL ...... 9 Step One: Identification of Water Quality-Limited Waters ...... 11 Step Two: Priority Ranking and Targeting ...... l3 step Three: TMDL Development ...... 14 Step Four: Implementation of Control Actions ...... 16 Step Five: Assessmentof Water Quality-Based Control Actions ...... 16 CHAPTER 3 - DEVELOPMENT AND IMPLEMENTATION OF THE TMDL ...... 19 Development of the TMDL ...... 19 The TMDL objective ...... 19 The TMDL Process ...... 19 Selection of Approach ...... 20 The PhasedApproach ...... 22 Approval of TMDLs by EPA ...... 23 Implementation of the TMDL ...... 23 NPDES Process for Point Sources...... 23 State or Local Processfor Nonpoint Sources ...... 24 Assessment of the TMDL ...... 25 CHAPTER 4 - EPA AND STATE RESPONSIBILITIES ...... 27 EPA/State Agreements ...... 27 State Responsibilities ...... 27 Identification of Water Quality-Limited Waters Still Requiring TMDLs ...... 27 Identification and Scheduling of Targeted Waterbodies ...... 29 TMDL Development ...... 29 Continuing Planning Process ...... 29 Water Quality Management Plan...... 30 Public Notice and Participation ...... 30 Reporting ...... 31 Other Specific Responsibilities ...... 31 EPA Responsibilities ...... 32 Review of 303 (d) lists ...... 32 TMDL Review and Approval ...... 32 Program Audits ...... 33 Technical Assistanceand Training ...... 33 Guidance Documents and Reports ...... 33 EPA Headquarters Responsibilities ...... 33 EPA Regional Responsibilities ...... 33

ii Page APPENDIX A- RELATIONSHIP TO OTHER GUIDANCE...... 35 Monitoring Guidance...... 35 Cooperative Monitoring/Citizen Volunteer Monitoring Guidance...... 35 Waste and Allocation Technical Guidance...... 36 Technical Support Document for Water Quality-Based Toxics ...... Control 36 PermitWriters Guidance ...... 37 Nonpoint Source Guidance...... 37 APPENDIX B - SUPPORTING PROGRAMS...... 38 EPA Water Quality Criteria and Standards ...... 38 Section305(b) -- Water Quality Assessment ...... 39 Section304(l) - Impaired waters ...... 40 Section319 - Nonpoint SourceProgram ...... 40 Section 314 - Clean Lakes Program...... 41 Section 320 - National Estuary Program...... 41 Monitoring Program ...... 41 Effluent Limitation Guidelines and Standards...... 41 NPDES Permitsand Individual Control Strategies ...... 42 Marine and Estuarine Waters...... 42 Groundwater ...... 43 CERCLA ...... 43 SARA ...... 44 APPENDIX C - SCREENINGCATEGORIES ...... 45 APPENDIX D - SELECTEDTECHNICAL CONSIDERATIONS ...... 48 Design Conditions ...... 48 MathematicalModels ...... 48 Pollutant Allocation Schemes...... 51 Multiple Discharges...... 51 Allocation Tradeoffs ...... 52 Persistentand/or Highly BioaccumulativeToxic Pollutants ...... 52 Use of Two-Number Criteria...... 52 SedimentResults ...... 53 APPENDIX E- MATHEMATICAL MODEL SUPPORT...... 54 APPENDIX F - GENERAL EPA/STATEAGREEMENT OUTLINE FOR DEVELOPMENTOF TMDLS ...... 56 APPENDIX G - CAUSES AND SOURCES OF POLLUTION...... 57 LIST OF ACRONYMS ...... 58 CHAPTER 1 - INTRODUCTION AND EXECUTIVE SUMMARY

Purpose and Summary together may contribute to a waterbody’s impairment. The purpose of this guidance document is to explain the programmatic elements and Chapter Two of this guidance document requirements of the TMDL process as estab- provides a description of the TMDL process lished by section 303(d) of the Clean Water in the context of the water quality-based ap- Act and by EPA’s Water Quality Planning proach to pollution reductions. This ap- and Management Regulations (40 CFR Part proach includes the identification and 130). A TMDL, or total maximum daily load, priority ranking of water quality-limited wa- is a tool for implementing State water quality ters, the targeting and scheduling of high standards and is based on the relationship priority waters, the development of TMDLs, between pollution sources and in-stream and the implementation of control actions water quality conditions. The TMDL estab- that should result in the attainment of water lishes the allowable loadings or other quan- quality standards. Assessment for water tifiable parameters for a waterbody and quality standards attainment provides the in- thereby provides the basis for States to estab- formation needed to identify water quality- lish water quality-based controls. These limited waters and for the evaluation of the controls should provide the pollution reduc- TMDL and control actions. tion necessary for a waterbody to meet water quality standards. The development and implementation of the TMDL establishes the link between Section 303(d) of the Act establishes the water quality standards assessment and TMDL process to provide for more stringent water quality-based control actions. The water quality-based controls when technol- third chapter of this document describes how ogy-based controls are inadequate to a State should proceed with developing achieve State water quality standards. When TMDLS once waters are targeted for action implemented according to this guidance, the and then how to implement them. Special TMDL process can broaden the opportunity consideration is given to such issues as ade- for public participation, expedite water qual- quacy of data and information, how to con- ity-based National Pollutant Discharge sider nonpoint source contributions, and Elimination System (NPDES) permitting, when to use a modified approach, called the and lead to technically sound and legally phased approach, that results in a TMDL defensible decisions for attaining and main- with special requirements. Implementation taining water quality standards. In addition, of the TMDL is discussed in terms of the the TMDL process provides a mechanism mechanisms that are available to reduce for integrating the management of both the both point and nonpoint loads. point and nonpoint pollution sources that The final chapter of this guidance describes the specific roles and responsibilities

1 that the States and EPA have in implement- required pollution control mechanisms are ing CWA section 303(d). EPA review and not sufficient or stringent enough to imple- approval of lists of waters submitted by the ment the water quality standards applicable States, the priority rankings of these waters, to such waters. and the TMDLS are set forth in the Water Quality Planning and Management Regula- More intensive assessments of water tion. This guidance presents a detailed dis- quality and an evaluation of pollution cussion of the submission of lists and sources should be conducted where water TMDLs, and the review and approval pro- quality standard violations occur or where cesses. The States’ responsibility to involve indications of declining water quality or hab- the public in the TMDL processis also high- itat loss are observed A TMDL should be lighted in this chapter. The value and im- developed and appropriate control actions portance of public participation is also taken on all pollution sources and follow-up emphasized throughout the document. monitoring should be conducted to assure that water quality standards are met. If fol- This guidance focuses on the program- low-up monitoring indicates that water qual- matic aspectsrather than the technical issues ity standards are not or will not be met, a of the TMDL process. Numerous technical revised TMDL is required. guidance manuals have been developed by EPA to assistStates in calculating wasteload Lack of information about certain types allocations (WLA). A list of these manuals of pollution problems (for example, those can be found in Appendix A along with a associatedwith nonpoint sourcesor with cer- description of other relevant guidance docu- tain toxic pollutants) should not be used as a ments. A brief description of selected tech- reason to delay implementation of water nical considerations can be found in quality-based controls. When developed ac- Appendix D and information about EPA cording to a phased approach, the TMDL supported models can be found in Appendix can be used to establish load reductions E. The other appendices provide the reader where there is impairment due to nonpoint with useful and relevant information such as sources or where there is a lack of data or descriptions of related water quality pro- adequate modeling. EPA regulations programs (Appendix B) and a general outline of vide that load allocations for nonpoint an EPA/State agreement for TMDL devel- sources may be based on “gross allotments” opment (Appendix F). (40 CFR 130.2(g)) depending on the availability of data and appropriate techniques Policies and Principles for predicting loads. In addition, before approving a TMDL in which some of the load To achieve the water quality goals of the reductions are allocated to nonpoint sources Clean Water Act, EPA’s first objective is to in lieu of additional load reductions allo- ensure that technology-based controls on cated to point sources,there must be specific point sources are established and main- assurancesthat the nonpoint source reduc- tained. Where such controls are insufficient tions will in fact occur. Therefore, this guid- to attain and maintain water quality stan- ance provides that in specific situations, the dards, water quality-based controls are re- TMDL must include a schedule for the im- quired. Under the authority of section plementation of control mechanisms, moni- 303(d) of the Clean Water Act, EPA expects toring, and assessment of standards States to develop TMDLs for their water attainment. If standards are not attained, a quality-limited waters where technology- TMDL revision is required. Data collected based effluent limitations or other legally through monitoring would then be useful in revising the TMDL. While this phased ap-

2 PRINCIPLES

Biedd Sobmissioo of L&s. Every two years,States will submit their required 303(d) identification of water quality-limitedwaters still nccdingTMDL6including a priority ranking of waterbodies to EPA. These lists may be included with a State’sbier&l 305(b) report or as a separatereport submitted at the sametime as the 305(b) report. (*pageW Priority TMDI.8. Along with the biumial submission of 303(d) lists, States will identify high priority waters targeted for TMDL development over the next two years. (See page 29.) Approach far TMDL Development. When specific criteria are met, a TMDL with additional specifi~tions for monitoring and implementation under the phased approach should be developed to provide for immediate pollution reduction and for collection of additional information. (Seepage 14 and 22.) Impluncntath of Controls Based on TMDLS. States will continue to improve and maintain point soura controls through WLAs and NPDES permits while implementing and mahhing nonpoint source controls through LAS and State or local requirements (see page 23.) Nonpdot Source Controls. LAs for nonpoint sourceswill be accompaniedby a description of nonpoiut source load reduction goals and the procedure for reviewing and revising nonpoint source controls. Such descriptions will be referenced in reviewing TMJJLS for approval (See page 24.) lbe Schedolc. TMDLS will be developed on a schedulenegotiated with EPA Regional offices. Tie schedules for the review of TMDLs will also be negotiated with EPA Regional 05ce5, but will occur within the statutory requirement of 30 days. (See pages29 and 32.) Geography Targeting. States should develop TMDLs that account for both point and nonpoint sourceson a geographically targeted waterbody basis. Geographically targeted waterbodies could include segments,basins, and watershedsas defined by the States. (Seepage 14.) ‘Ikreatened Good Quality Waters. States are expected to include threatened good quality waters in their identifxation and prioritization of waters still needing TMDLs. (Seepage 12) Publk putid~thn. Statesare expectedto eusureappropriate public participation in the TMDL development and implementation process. (See page 30.) EO~~IIIWO~~ Indicators. States should measurethe effectivenessof control adions by monitoring changes in ambient water quality or biological conditions. Measuring environmental progressor showing environmental results is a critical need and has become a key element in EPA’s strategic planning process.

preach requires additional monitoring of the CPR 130.7(b). The identified waters should waterbody to evaluate the effectiveness of include those impaired due to point and non- nonpoint source management measures or point sources and may include threatened more stringent effluent limitations, it does good quality waters. EPA is establishing not delay the establishment of such control with this guidance that States should submit mechanismswhere there is a lack of informa- to EPA, in conjunction with the 305(b) water tion. quality assessmentreports, in April of 1992, the list of water quality-limited waters that As required by the Clean Water Act, still require TMDLs. Every two years there- States are to identify and report to EPA their after, a State should update its list of 303(d) water quality-limited waters. These waters waters and submit it with the 305(b) report. are to be identified according to the provis- This guidance describes in detail the identi- ions established in EPA’s Water Quality fication processand the specific information Management and Planning Regulation at 40 that should be submitted to EPA

3 As required by the Clean Water Act, and reaffirm the existing regulatory require- Statesare to rank by priority all waters need- ments. They are intended to help States ing TMDLS. Since each State has a unique managetheir surfacewater quality programs organizational arrangement for the protec- in a manner consistent with the intent and tion of water quality, this guidance does not requirements of section 303(d) of the CWA prescribe how a State should set its priorities. and the Water Quality Planning and Man- However, priority ranking should result in agement Regulations in 40 CFR 130. These the identification of targeted waterbodies principles are discussed throughout this for which immediate TMDL development guidance. should be undertaken. In the biennial sub mission of their updated list of 303(d) waters, t&an Wafer Act Sextin 303(d) EPA expects States to identify the waters targeted for TMDL development in the Section 303(d) of the Act (see next page) forthcoming two years. requires States to identify waters that do not or are not expected to meet applicable water Historically, the water quality-based pol- quality standards with technology-based lution control program has focused on re- controls alone. Waters impacted by thermal ducing the load of chemical contaminants discharges are also to be identified. States (e.g. nutrients, biochemical oxygen demand, are required to establish a priority ranking metals) to waterbodies. EPA has defined for these waters, taking into account the pol- the terms load, loading capacity, and load lution severity and designated uses of the allocation in regulations and technical guid- waters. ance documents so that wasteload allocations can be calculated. Chemical Once the identification and priority contaminant problems will continue to con- ranking of water quality-limited waters are stitute a major portion of pollution control completed, States are to develop TMDLS at efforts and the terms “load” and “load reduc- a level necessaryto achieve the applicable tion” are used throughout this document. State water quality standards. Completed However, it is becoming increasingly appar- TMDLS must allow for seasonal variations ent that in some situations water quality stan- and a margin of safety that accounts for any dards - particularly designated uses and lack of knowledge concerning the relation- biocriteria - can only be attained if non- ship between effluent limitations and water chemical factors such as hydrology, channel quality. morphology, and habitat are also addressed. EPA recognizes that it is appropriate to use States are required to submit to EPA the the TMDL processto establish control mea- titers identified and loads established” for sures for quantifiable non-chemical param- review and approval by EPA If disap eters that are preventing the attainment of proved, EPA will establish the TMDLs at water quality standards. Control measures, levels necessaryto implement the applicable in this case, would be developed and im- water quality standards. For waters that are plemented to meet a TMDL that addresses not identified under sections 303(d)(l)(A) these parameters in a manner similar to and (l)(B) as being water quality-limited, chemical loads. As methods are developed States are to estimate TMDLS for informa- to address these problems, EPA and the tion purposes. Stateswill incorporate them into the TMDL process. Subsections4(A) and (B) were added to CWA section 303(d) with the 1987 amend- The principles (see page 3) established ments in order to ensure consistencywith the by EPA in this guidance reflect thesepolicies water quality standards process for use clas-

4 FEDERAL WATER POLLUTION CONTROL ACT Section 303(d)

(l)(A)~Sratcshall~thoJcwataswithinitrbollndaricsforwhichrhc~limiroaionrnquindbyscction 3Ol(b)(l)(A)andsection3Ol(b)(l)(B)amnotstrtngentenoughwim@ementanywaterqualirys@ndatd applicable w such waters. Thc State shall establish apiarirV rankingforsuchwatm, taking info accounlthcsev~oftht pollu&andtheuseswbcmadeofsuchwaters.

(C)EochStcrtcshallcnablihforthcwotasidaujFdin~a~~(l)(A)ofrhirsubsccrioyandinaccadancrwith thepriodyr~gthetotalmmrimwn daily&ad,forthosepol&ntswhichtheAdministratoridemif%undersectum 304(a)(2) as mitabk fbr such calada~ Such &ad shall be establishedat a level necessaryto implement the applicablr waterqualitystanda& withswoMIv~~andammgnofs~which~okcrintooccbwuanyIack ofknow&dgeconcemingtherelationshipbetweencffluMlimita&nsand waterquality.

(2) Each State shall submit to theAdmini.stratorfnun tune to tinq with thefirst such submission not later than one hundred and eighty days ajier the date of publication of the )?rst identification of pollutants under section 304(a)(2)(D), fop his approval the waters iden@ed and the loads establishedunder paragraphs (l)(A), (I)(B), (I)(C), and (I)(D) of this subsection Ihe Administrator shall either opptove or d&p-e such identtfiation and loadnorlaurthan~daysafrarhcdau~~mirsionIfthcAdminimarovappwcrsuch~and1004 such State shall incorporate them into its aurotr p&n under subsection (e) of this section If the Administrator ~~~suchidauiForiovrandroacl,hcJhollnotlara~~dCIyfathCdCltCOfSllCh~ap~~~~ suchwaraJinswhStarcandcnablihJuch~fotsuchwarasarhc&~ nuessary w implement the water qualrjlsrandardtapplicab&wsudrwataJ~upovtsuch~~~andcstab~~cnrthcStatcshallincovporatc them into its cutrent plan under subsection (e) of this section (3) For the specificpurpose of developinginf~tion, eachState shah idcnrjfLall waterswithin its bour&&s which it has not identzw unda paragraph (l)(A) and (I)(B) of this subsectionand tstimauforsuchwattrsthetotd -dailyloadwithseasonalv- and matgim of safety,fat thosepol&mts which the Administrator ident@ unda section 304(a)(2) as suitable for such calculation and for thamal dischaqes, at a level that would assurepmtution andpqmgation ofa balancedindigenouspoyndation OfFh, shellftsh and wikilife (4) LLMIZATIONS ONREVISION OF CEBTMNEFFLUENTLIM7ZATIONS.--- (A) STANDABD NOT AlXAINED.-For waters iden@ed under paragraph (I)(A) whar the applicable water QualiryJrandardhasnoJyabun~any~~barcdonatosalmmimwndai?,locldorothawarrr loodallocaabvrurablirhcdunda~sccnbnmrrybrmtirc4~jf(i)rhcnunulative~~orfallsrrchnvircdcfflucnt Iimitations basedon such totalmaximum dailyloadorwasteloada&xatumwillassuretheattainment of such wata qualiy standard or (ii) the designateduse which it not being attained is ronoved in acco&nce with reguhuions establishedunda this section (B)STANDARDAlTAINED.--Forwatersidentt$uiunderparagraph (l)(A) wherethequalityofsuch watersequals or aceeds levels necessatyw ptxrtect the designatrd usefor such waters or othenvise q&d by applicable wata qua&y standard, any e@ent limitation based on a total maximum dOi&lOdtWoshaWtlSt~hldt.llhUh establishedunda this section, or any wata quality standard establishedunder this section, or any otherpemtimig ~zndard may be revisedor$v if such revision is subjectto and consistentwith the ant&gradation poliq estabtlishea unda this section

5 sification and with the NPDES antibackslid- Wasteload allocation (WLA) -The por- ing requirements. tion of a receiving water’s loading capacity that is allocated to one of its existing or future point sourcesof polhrtioa WLAs con- stitute a type of water quality-based effluent limitation. (40 CF’R 1302(h)) EPA’s Water Quality Planning and Man- agement Regulation at 40 CPR Part 130 es- Total maximum daily load (TMDL) - tablishes the program and policies that The sum of the individual WLAs for point implement CWA section 303(d) require- sources and LAs for nonpoint sources and ments. Section 130.7 describes the TMDL natural background. If a receiving water has process and the State’s responsibility for only one point source discharger, the TMDL identifying waters still requiring TMDLs, is the sum of that point source WLA plus the setting priorities and developing TMDLS, L&i for any nonpoint sources of pollution submitting the waters identified with priority and natural background sources,tributaries, rankings and the TMDLS to EPA for ap- or adjacent segments. TMDLS can be ex- proval, and the incorporation of the TMDLS pressed in terms of either mass per time, into the State’s Water Quality Management toxicity, or other appropriate measure that Plan. relate to a State’s water quality standard. If Best Management Practices (BMPs) or To implement the program, the regula- other nonpoint source pollution control action establishes the following definitions for tions make more stringent load allocations loading capacity, load allocation, wasteload practicable, then WLAs can be made less allocation, total maximum daily load, water stringent. Thus, the TMDLprocess provides quality-limited segments and water quality- for nonpoint source control tradeoffs. (40 limited segments still requiring TMDLs. A CFR 1302(i)) definition for margin of safety (MOS) is also In pactice, the terms lXfDL and U2.A provided. have at times been incorrectly used inter- Loading capacity (LC) - The greatest changeably instead of considering both LA amount of loading that a water can receive and WLA as components of a XUDL. A TiUDL, as tefeteced in thir guidance, in- without violating water quality standards. (40 CFR 1302(f)) cludes both WUs and LAS, estublirhea’ in accordance with EPA ‘s regularionr Load allocation (LA) - The portion of a receiving water’s loading capacity that is at- Water quality-limited segments--Those tributed either to one of its existing or future water segments that do not or are not ex- nonpoint sources of pollution or to natural pected to meet applicable water quality stan- background sources. Load allocations are dards even after the application of best estimates of the loading, which may technology-based effluent limitations re- range from reasonably accurate estimates to quired by sections 301(b) and 306 of the Act. gross allotments, depending on the availabil- (40 CPR 130.20’)) Technology-based con- ity of data and appropriate techniques for trols include, but are not limited to, best predicting the loading. Wherever possible, practicable control technology currently natural and nonpoint source loads should be available (BFT) and secondary treatment. distinguished. (40 CFR 130.2(g)) Water quality-limited segments still requiring TMDLs -- Segments identified through a process established by paragraph 130.7(b)(l) of EPA’s Water Quality Plan- dam5 afier the implementation of water quul- ning and Management Regulation. Waters ity-basedcontrol actions would retain its water need TMDLS when certain specified pollu- quality-limited status but would no longer be tion reduction requirements (identified in on a State’s303(d) list of waters still requiring the regulation under subparagraphs EUDLS. (b)(l)(i), (ii), and (iii)) are not stringent enough to implement water quality stan- Margin of Safety (MOS) - A required dards for such waters. The specified pollu- component of the TMDL that accounts for tion controls include technology-based the uncertainty about the relationship be- effluent limitations required by sections tween the pollutant loads and the quality of 301(b) and 306 of the Clean Water Act and the receiving waterbody. (CWA section other appropriate requirements that can 303(d)(l)(C)) The MOS is normally incor- provide a more stringent level of treatment porated into the conservative assumptions than federally-required technology-based used to develop TMDLs (generally within effluent limitations. (40 CFR 130.7(b)( 1)) the calculations or models) and approved by EPA either individually or in State/EPA ThFFabcumem contaim the terms 303(d) agreements. If the MOS needs to be larger waters and 303(d) kts. 7hese waters (and than that which is allowed through the con- waters on the 303(d) l&s) are those water servative assumptions, additional MOS can quality-limited segments that still require be added as a separate component of the 7MDLs as defined by the regulation l?tus, a TMDL (in this case,quantitatively, a TMDL watersegmentthat meetsits waterquulitystan- = LC = WLA + LA + MOS).

7 CHAPTER 2 - THE WATER QUALITY-BASED APPROACH TO POLLUTION CONTROL

The Water Quality Planning and Man- are identified through the development of a agement Regulation (40 CFR 130) links a TMDL under section 303(d). number of Clean Water Act sections,including section 303(d), to form the water quality- Previous practices for implementing based approach to protecting and cleaning 303(d) have focused primarily on point up the nation’s waters (diagrammed in Fig- sources and wasteload allocations (WLA). ure 1). This chapter describes the overall All water quality-based permit limits are approach for the development of TMDLs based on a WLA. The WLA is either re- and subsequent implementation of water viewed individually by EPA or where there quality-based point and nonpoint source exists a State/EPA technical agreement, is pollution control measures based on water developed consistent with that agreement.1 quality standards. Other related guidance In recent years nonpoint source contribu- on various aspectsof the water quality-based tions to water quality problems have become approach are described in Appendix A. better understood and it is now clear that EPA and State implementation of 303(d) The water quality-based approach em- must encompass nonpoint source pollution phasizes the overall quality of water within a problems and seek to address problems oc- waterbody and provides a mechanism curring over large geographic areas. As a through which the amount of pollution en- consequence, this document describes a tering a waterbody is controlled basedon the more rigorous process for implementing intrinsic conditions of that body of water and 303(d) and reinforces the need to develop the standardsset to protect it. This approach TMDLs that include load allocations (LA) begins with the determination of waters not as well as wasteload allocations. meeting (or not expected to meet) water quality standards after the implementation As shown in Figure 1, the water quality- of technology-based controls (such as BIT basedapproach contains the following steps: and secondary treatment). Waters identified through this process are considered 1. Identification of water quality- water quality-limited and must be priori- limited waters still requiring TMDLs. tized. An overall plan to manage the excess pollutants in each waterbody can then be 2. Priority ranking and targeting. developed. The necessarylimitations on the introduction of pollutants to the waterbody 3. TMDL development. 1 USEPA. 1985. Guidance for State Water Monitoring and Wasteload Allocation Program. OW/OWRS, EPA 440/4-85-031.Washington, D.C. Figure 1 General Elements of the Water Quality-Based Approach

10 4. Implementation of control actions. Identi@ing Waters Still Requiring TMDLs: 40 CFR 130.7(b) 5. Assessment of water quality-based control actions. (b)(l) Each State shall identify those :crrz segmentsstill requiring WLAsaAs within its boundaries for which: Steps 1, 2, and 3 are addressed by the CWA in section 303(d). Steps 4 and 5 are (i) Technology-based efhent hitations re- integral parts of the process and are briefly quir&byscctions301(b),306,307,0rother described in this document. sections of the au; States are to review and revise water (ii) More stringentcfZlucat limitations (ichd- quality standards, as necessary,every three ing prohibitions) required by either State years and NPDES permits are to be re-eval- or local authority prcscned by section 510 uated and issued every five years. The water of the AU, or Federal authority (e.g., law, quality-based approach links these two pro- regulation, or treaty); aad cessesand is, therefore, an ongoing process of evaluation and modification. In addition (iii) Other pollution control requiremeats (e.g., to standards and permits revisions, section bestmanagement practices) rquired by 319(b) nonpoint source (NPS) management lod, State, or Federal authority plans can and should be continually updated are not stringent enough to implement any water as well. quality standard applicable to such waters. stepone: Iih@c~hn of wuter Qtdity-limited Waters The most widely applied water pollution controls are the technology-based effluent The water uality-based approach to pol- limitations required by section 301(b) and lution control 1 egins with the identification 306 of the Clean Water Act. In some cases, of problem waterbodies. State water quality a State or local authority may establish en- standards form the basis and “yardstick” by which States can assessthe waterbody status forceable requirements beyond technology- and implement needed pollution controls. based controls. Examples of such State water quality standards include three requirements may be those that (1) provide elements: designated uses for the water- more stringent NPDES permit limitations to body, criteria (physical, chemical, and bio- protect a valuable water resource or (2) pro- logical) to protect the designated uses, and vide for the management of certain types of an antidegradation statement. States need nonpoint source pollution. to identify those waters not meeting any one of these components of water quality stan- To exempt a water quality-limited water dards. from the TMDL process,the pollution control requirements cited in the regulation EPA’s Water Quality Planning and Man- under 130.7(b)(i),(ii), and (iii) (see box) agement Regulation establishesthe process must be established and enforced by Fed- for identifying water quality-limited seg- eral, State, or local laws or regulations and ments still requiring TMDLS. Waters re- be stringent enough that, when applied, the quireTMDLswhen certainpollutioncontrol receiving waterbody will meet water quality requirements (see box) are not stringent standards. These requirements must also be enough to implement water quality stan- specifically applicable to the particular water dards for such waters. quality problem and, if not yet implemented, a schedule for the timely implementation of such requirements must be established. going monitoring programs to assess Chapter 4 contains more specific require- whether water quality standards are being ments pertain@ to identification of water met, and to detect trends. quality-limited waters still requiring TMDLs States assesstheir waters for a variety of (see p. 27). purposes, including the targe of cleanup activities, assessingthe extentY 0 contamina- Identification of threatened good quality tion at potential Superfund sites, and for waters is an important part of thrs approach. meeting federally mandated reporting re- Adequate control of new discharges from quirements. While the identification of either point or nonpoint sourcesshould be a water quality-limited waters may appear to high priority for States to maintain the exist- be a major task for the States, a significant ing use or uses of these waterbodies. In the amount of this work hasalready begun or has identification of threatened waters it is important that the 303(d) processconsider the been corn leted under sections 305(b), 304(1),314P a),and319(a)oftheCleanWater water quality standards program to ensure Act as amended in 1987. (Appendix B ro- that a State’s antidegradation policies as es- vides a summary of these supporting CL A tablished in State law are followed. Prw=.) By identifying threatened good quality Section 3!5(b) requires Statesto prepare waters, States take a more proactive, “pollu- a water quahty mventoxy every two years to tion prevention” a preach to water quality document the status of waterbodres that management (see & low). have been assessed. Under section 304(l), Statesidentified all surface waters adversely Pollution Prevention Advantages affected by toxic (65 classesof compounds), conventional (such asBOD, total suspended consistent with 40 CFR 130.7(c)(l)@) which re- solicls, fecal coliform, and oil and grease), quircsthatTMDLsbcestablishedforallpollutants and nonconventional (such as ammonia, thatprevcntorafcclqKxtedtoprcvcntwataqual- chlorine, and iron) pollutants from both ity standards from being achieved. point and nonpoint sources. Under section EncouragesStates to maintain and protect cxkting 314(a), States identified a list of publicly water quality. owned lakes for which uses are known to be impaired by point and nonpoint sources. Easier and less costly in the long term to prevent Section 319 State AssessmentReports iden- impairments rathcr than retrofit umtrols to clean tified waters adversely affected by nonpoint up pollution proMeM. sources of pollution. Lists prepared to sat- Meets EPA objectives to support the State’s ml- isfy re uirements under section 30S(b), lcuion of data on impaucd or thrcatcncd waters. 304(l), %4(a) and 319 should be very useful in preparing 303(d) lists. Other existing and readily available data Each State may have different methods and information sources should be utilized for identifying and compiling information on in preparing section 303(d) lists. See, for the status of its waterbodies depending on its example, Appendix C, which presents specific programmatic or cross-program- screening categories similar to those found matic needs and organizational arrange- in current regulatiqns. promulgating the ments. Typi ) states utilize both existmg 304(l) requirements. Figure C-l m the Ap- information =!?an new data collected from on- pendix depicts a sample processfor identify- 2 40 CFR DO.10 (d)(6)

12 ing 303(d) waters. Other data sources are Priority Setting Documents to NPnpnmtSPutrx; Control(OWRS, Jti 1987). Amended, March 1988. The Toxic Chemi- cal Release Inventory (TRI) developed under Title III, Superfund and Reauthonza- Betttr (OW and OPPE, August tion Act (SARA) is an important informa- 1989,EPA 506I2-89~). tion source as well as any relevant State-run database. First Edition (OWRS, EPA 440/S- e Section 303(d) requires Statesto identify those water quality-limited waters needing Second Edition (OWRS, EPA TMDLs. States should regularly update tiite!g their lists of waters (or the databaseswhich store the information to produce the lists) as assessmentsare made and report these lists to EPA once every two years. Statesshould include, in their biennial 303(d) lists, information on which waterbodies have been added or deleted from the list and which According to EPA’s State Clean Water waterbodies were assessedsince the last re- Strategy document: “Where all water quality porting period. (See page 27 for further de- problems cannot be addressedimmediately, tails on submission of lists to EPA) EPA and the States will, using multi-year approaches, set priorities and direct efforts and resources to maxim& environmental Step Two: Priority RanRing and benefits by dealing with the most serious Targeting water quality problems and the most valuable and threatened resources first.” Once waters needing additional controls have been identified, a State prioritizes its Targeting high priority waters for TMDL list of waters using established ranking pro- development should reflect an evaluation of cessesthat should consider all water pollu- the relative value and benefit of waterbodies tion control activities within the State. within the State and take into consideration Priority ranking has traditionally been a pro- the following: cess defined by the State and may vary in complexity and design. A priority ranking l Risk to human health and aquatic should enable the State to make efficient use life. of its available resourcesand meet the objectives of the Clean Water Act. l Degree of public interest and support. The Clean Water Act states that the priority ranking for such waters must take into account the severity of the pollution and the l Recreational, economic, and aes- uses to be made of such waters. Several thetic importance of a particular documents (see box) are available from EPA waterbody. to assist States in priority setting. l Vulnerability or fragility of a particular waterbody as an aquatic habitat.

13 Immediate programmatic needs such Advantages to Long-range Schedules as wasteload allocations needed for permits that are coming up for revi- 0 En~int~witllthcpermitting sions or for new or expanding dis- cyclq the water quality standards revision& charges, or load allocations for and other required water quality managc- needed BMPs. ment activith. 0 Allows for long-term monitoring which may Waters and pollution problems iden- be needed to assesscontrol action. tified during the development of the section 304(l) long list.” l Setsconsistency in developing lT4DI.s.

Court orders and decisions relating 0 Establishcsabasisforscttingovcm.llwater to water quality. quality-priorities 0 Supports a geographic approach for TMDL National policies and priorities such dcvclopmcaUfortargctcdwaferbodies. as those identified in EPA’s Annual Operating Guidance. States are required to submit their priority rankings to EPA for review. EPA expects uting point and nonpoint sources so that the all waters needing TMDLs to be ranked, water quality standards are attained for that with “high” priority waters - targeted for waterbody. The development of TMDLS TMDL development within two years fol- should be accomplished by setting priorities, lowing the listing process - identified. (See considering the geographic area impacted by page 29 for further details on submission of the pollution problem, and, in some cases, priorities to EPA) using a phased approach to establishing control measures based on the TMDL In order to effectively develop and implement TMDLs for all waters identified, The TMDL is developed using one or a States should establish multi-year schedules combination of three technical approaches that take into consideration the immediate to protect receiving water quality: the chem- TMDL development for targeted waterbod- ical specific approach, the whole effluent ies and the long-range planning for address- toxicity approach, and the biocrite- ing all water quality-limited waters still ria/bioassessment approach. The chemical requiring TMDLS. While it would be ex- specific approach is one where loadings are pected that these schedules would change evaluated in terms of the impact on physical- when a State’s priorities change in response chemical water quality conditions (e.g., dis- to “hot spots” or critical situations at any solved oxygen or toxicant concentrations). given time, a long-range schedule provides While an integrated approach that considers several advantagesto a State (see box). all three techniques is preferred for the protection of aquatic life, the chemical specific approach is usually the one used to address Step IVtme: TMDL Development loads that affect those water quality stan- For a water qualit@nited water that dards which protect human health. still requires a TMDL, a State must establish Many water pollution concerns are area- a TMDL that quantifies pollutant sources wide phenomena that are causedby multiple and allocates allowable loads to the contrib- dischargers,multiple pollutants (with poten-

14 tial synergistic and additive effects), or non- more data becomes available to develop sen- point sources. Atmospheric deposition and sitivity analyses and model comparisons. ground water discharge may also result in For TMDLS involving these non-traditional significant pollutant loadings to surface wa- problems, the margins of safety should be ters. As a result, EPA recommends that increased and additional monitoring re- States develop TMDLS on a geographical quired to verify attainment of water quality basis (e.g., by watershed) in order to effi- standardsand provide data needed to recal- ciently and effectively manage the quality of culate the TMDL, if necessary. surface waters. EPA regulations provide that load allo- The TMDL process is a rational method cations for nonpoint sources and/or natural for weighing the competing pollution con- background “are best estimates of the load- cernsand developing an integrated pollution ing which may range from reasonably sccu- reduction strategy for point and nonpoint rate estimates to gross allotments... A sources.The TMDL processallows States to phased approach to developing ‘IMDLS may take a holistic view of their water quality be appropriate where estimates are basedon problems from the perspective of instream limited information. The phased approach conditions. Although States may define a is aTMDL that includes monitoring require- waterbody to correspond with their current ments and a schedule for re-assessingTMDL programs, it is expected that States will con- allocations to ensure attainment of water sider the extent of pollution problems and quality standards. Uncertainties that cannot sources when defining the geographic area be quantified may also exist for certain pol- for developing TMDLs. In general, the geo- lutants discharged primarily by point graphical approach for TMDL development sources. In such situations a large margin of supports sound environmental management safety and follow-up monitoring is appropri- and efficient use of limited water quality ate. program resources. In caseswhere TMDLs are developed on watershed levels, States Where nonpoint source controls are in- should consider modi@@ permitting cycles volved, the phased approach is also neces- so that all permits in a given watershed ex- sary. Under the CWA, the only federally pire at the same time. enforceable controls are those for point sourcesthrough the NPDES permitting pro- For traditional water pollution prob- cess. In order to allocate loads among both lems, such as dissolved oxygen depletion and nonpoint and point sources, there must be nutrient enrichment, there are well validated reasonable assurancesthat nonpoint source models that can predict effects with known reduction will in fact be achieved. Where levels of uncertainty. This is not true for such there are not reasonable assurances,under non-traditional pollution problems as urban the CWA, the entire load reduction must be stormwater runoff and pollutants that in- assignedto point sources. With the phased volve sediment and bioaccumulative path- approach, the TMDL includes a description ways. Predictive modeling for these of the implementation mechanisms and the problems therefore uses conservative as- schedule for the implementation of non- sumptions, but in many casesthe degree of point source control measures. certainty cannot be well quantified until

3 4ocFR Em(g). By pursuing the phased approach where plementation of nonpoint source controls applicable, a State can move forward to im- such as the installation of Best Management plement water quality-based control mea- Practices (BMPs). Section 319 State man- sures and adopt an explicit schedule for agement programs can be a useful tool to implementation and assessment. States can implement nonpoint source control mea- also use the phased approach to address a sures and ensure improved water quality. greater number of waterbodies including Many BMPs, however, may be implemented threatened waters or watersheds which evenwhere regulatory programs do not exist. would otherwise not be managed. Specific In such cases,a State needs to document the requirements relating to the phased ap coordination which may be necessaryamong preach are discussedin Chapter 3. State and local agencies,landowners, opera- tors, and managers and then evaluate BMP Step Four: Imp~mentation ofConed implementation, maintenance, and overall effectivenessto ensure that load allocations Actins are achieved. Chapter 3 dkcusses some of Once a TMDL or a phased TMDL has the technical issues associated with im- been established for a waterbody (or water- plementation of nonpoint source control shed) and the appropriate source loads de- measures. veloped, implementation of control actions should proceed. The State or EPA is respon- Step Five: Assessmentof W&r sible for implementation, the first step being Qualify-Based Control to update the water quality management Actions plan. Next, point and nonpoint source controls should be implemented to meet Throughout the previous four steps, wasteload allocations and load allocations, monitoring is a crucial element of water respectively. Various pollution allocation quality-based decision making. In this step, schemes (i.e., determination of allowable monitoring provides data for an indepen- pollution among different pollution sources dent evaluation of whether the TMDL and in the same waterbody) can be employed by control actions that are based on the TMDL Statesto optimize alternative point and non- protect or improve the environment and are point source management strategies. sufficient to meet changing waterbody protection requirements such as revised water The NPDES permitting process is used quality standards or changing pollution to limit effluent from point sources. Chapter sources(e.g., urbanization). 3 provides a more complete description of the NPDES process and how it fits into the Monitoring programs often begin with water quality-based approach to permitting. baseline monitoring. Such monitoring Construction decisions regarding publicly should not be regarded as a prerequisite to owned treatment works (PUIWs) and ad- implementing control measuresfor a water- vanced treatment facilities must also be body. If monitoring has not yet begun, con- based on the most stringent of technology- trol measures and monitoring should be based or water quality-based limitations. implemented simultaneously to assure that These decisions should be coordinated so pollution abatement activities are not de- that the facility plan for the discharge is con- layed. sistent with the limitations in the permit. In the caseof point sources,assessments In the case of nonpoint sources, both are facilitated in that dischargers are re- State and local laws may authorize the im- quired to provide reports on compliance

16 with NPDES permit limits. In some in- States should also ensure that effective stances,dischargers may also be required in monitoring programs are in place for evalu- the permit to assessimpact of their discharge ating nonpoint source control measures. on the receiving water. A monitoring re- EPA recognizesmonitoring asa high priority quirement can be put into the permit as a activity in a State? nonpoint source manage- special condition as long as the information ment program. To facilitate the im- is collected for purposes of writing a permit plementation and evaluation of NPS limit. States are also encouraged to use in- States should consult current guid- novative monitoring programs (e.g., cooperative mo itoring and volunteer monito J* ) to provide for adequate point and nonpoint source monitoring coverage.

4 USEPA. 1984. PIarm& and Manag& Cooperative Monitoring Projects. OWiOWRS. EPA 440/4-84418. Washingto& DC. 5 USEPA. 1990. Vduntccr Water Monitoring A Guide for State Managers. OW, EPA 440/4-90410. Washington, D.C. 6 55 FR 35265 August 28,199O. 7 USEPA. February, 1988. Draft Nonpoint Source Monitoring and Evaluation Guide. OW/NPS Branch. Washington, D.C. 8 USEPA. September 19,l989. Nonpoint Source Monitoring and Reporting Requirements for Watershed Implementation Grants. OW/NPS Branch. Washington, D.C.

17 CHAPTER 3 - DEVELOPMENT AND IMPLEMENTATION OF THE TMDL

Development of the TMDL establishing or modifying controls on pollutant sources. The TMDL process is an important element of the water quality-based approach. It The TMDL Process links the development and implementation of control actions to the attainment of water The total pollutant load to a waterbody is quality standards. This chapter expands the derived from point, nonpoint, and back- discussion introduced in Chapter 2 on how ground sources. Pollutant loads may be to develop TMDLs and implement controls transported into waterbodies by direct dis- for water quality-limited waters. Appendix charge, overland flow, ground water, or at- D and E provide supporting information on mospheric deposition. The TMDL concept some important technical considerations has successfully been applied to develop and EPA supported models for TMDL de- wasteload allocations for point source dis- velopment. charges in low flow situations where nonpoint sources are not a concern. TMDLs can The TMDL Objective and should be used, however, to consider the effect of all activities or processes that cause As stated in 40 CFR 131.2, “[water qual- or contribute to the water quality-limited ity] standards serve the dual purposes of es- conditions of a waterbody. Activities may tablishing the water quality goals for a relate to thermal changes, flow changes, sed- specific waterbody and serve as the regula- imentation, and other impacts on the aquatic tory basis for the establishment of water- environment. Control measures to imple- quality-based treatment controls and ment TMDLs, therefore, are not limited to strategies beyond the technology-based lev- NPDES authorities but should also be based els of treatment required by section 301(b) on State and local authorities and actions to and 306 of the Act.” Standards also contain reduce nonpoint source pollution antidegradation provisions to prevent the degradation of existing water quality. An example of how to apply such a TMDL might be in the control of excess The objective of a TMDL is to allocate sediment which causes loss of a beneficial allowable loads among different pollutant use of a waterbody. If standards, established sources so that the appropriate control ac- to protect against the loss of a beneficial use tions can be taken and water quality stan- (e.g., fish spawning), are not met and, if the dards achieved. The TMDL provides an process causing the problem (i.e., excess sed- estimate of pollutant loadings from all imentation) can be quantified, then it may be sources and predicts the resulting pollutant appropriate to use the TMDL process to concentrations. The TMDL determines the assess the adverse impacts and potentially allowable loads and provides the basis for set controls on the problem activity. In this

19 example, the activity might be urban devel- quality-based limits than those contained in opment for which effective controls can be a previously issued permit. In a limited num- implemented to reduce sediment loading to ber of cases, however, it is conceivable that the impacted waterbody. less stringent water quality-based limits could result. In these cases, permit limits The TMDL process distributes portions must conform to the antibacksliding provis- of the waterbody's assimilative capacity to ions contained in section 402(o) of the CWA. various pollution sources - including natural background sources and a margin of safety - Selection of Approach so that the waterbody achieves its water quality standards. The analyst may use predictive Figure 2 illustrates the critical decisions modeling procedures to evaluate alternative and the appropriate steps in the TMDL pro- pollution allocation schemes in the same cess for developing load allocations and im- waterbody. By optimizing alternative point plementing and evaluating control actions. and nonpoint source control strategies, the In some cases, as illustrated by the left side cost effectiveness and pollution reduction of the diagram, TMDL development can be benefits of allocation tradeoffs may be eval- straight-forward and relatively simple. In uated (see Appendix D). The approach nor- other cases, as depicted by the right side of mally used to develop a TMDL for a the diagram, a phased approach may be particular waterbody or watershed consists more appropriate. Regardless of which path of five activities (see box). is followed, the allocation of loads and establishment of control actions should ensure that all water quality-limited waters will TMDL Development Activities meet their standards.

• Selectionof the pollutant to consider. Once a waterbody is selected for action, an analyst must decide if the available data • Estimation of the waterbody assimilativeca- and information about the sources, fate, and pacity. transport of the pollutant to be controlled is adequate. The level of effort and scientific • Estimationof the pollution from all sources knowledge needed to acquire adequate data to the waterbody. and perform meaningful predictive analyses is often a function of the pollutant source, • Predictive analysisof pollution in the water- pollutant characteristics, and the geographi- body and determination of total allowable cal scale of the pollution problem. As de- pollution load. scribed in Chapter 2, modeling the fate and • Allocation (with a margin of safety) of the transport of conventional pollutants (e.g. allowing pollution amongthe different pol- biochemical oxygen demand) and point lution sourcesin a manner that water quality source contributions is better developed standardsare achieved. than modeling for non-traditional pollution problems. For certain non-traditional problems, if there are not adequate data and predictive tools to characterize and analyze In developing a TMDL it is important to the pollution problem with a known level of keep in mind certain constraints on the WLA uncertainty, a phased approach may be nec- portion that are imposed by antibacksliding essary- regulatory provisions. The WLA will normally result in new or more stringent water The phased approach is required when the TMDL involves both point and nonpoint

20 Rgura 2 D8vvt of TMWS for Tug8t8d W*tubodo8

IdontJfy 303(d) Tar@etod Watorbody

lord roductbm?

oovolop TMDL lndudh~ R8~OmOnt8 o*vdop TMDL hclu&g: . WLA8 for PS which - mt8h l titbfj tilllit Or l WLA8 for PS .8t8bi&h l3.W mt8 l LA8 for NPS 8nd B8tkglourd l ~8for~SWhkh SOurC88 - M8hbh or l M8rfJifl Of 88f l ty NPS control8 TiliEEPW . . hrf#fb Of uf8ty form l h8t8ll8tlon 8nd l v8k8tbn of NPS control8 .D8t8 CdkctiOfl . wQ8 888.8-t l Addltloml modolhg If naodad n of Schq&& I I Approval by EPA

Lngkmmt Control. 8nd Comgkt. RoqUrod D8t8 colkction 0 m p8rl’dt8 fOr #bOht 8-C. COntrOh 0 8t8tO ot iOCti vOCO88.8 fOr mt 8-C. COntrdr l Addltb~Imonltuhg l Fhd C8l&dONl Of mOdd8

WQS8 not rchioved of W&or QuaMy-

W088 8chkv.d t

R8mOVO W8terbOdy from 303(d) Ll8t sources and the point source WLA is based similative capacities and pollution alloca- on a IA for which nonpoint source controls tiOIlS. need to be implemented. There must be assurances that nonpoint source control In addition to the allocations for point measureswill achieve expected load reduc- and nonpoint sources, a TMDL under the tions in order to allocate a wasteload to a phased approach will establish the schedule point sourcewith a TMDL that also allocates or timetable for the installation and evalua- expected nonpoint source load reductions. tion of point and nonpoint source control In this case, a phased approach is required measures,data collection, the assessmentfor because the TMDL that is developed has water quality standards attainment, and, if additional requirements that provide these needed, additional predictive modeling. assurances. The scheduling with this approach should be developed to coordinate all the various ac- Despite the additional requirements of tivities (permitting, monitoring modeling the phased approach, States may actually etc.) and involve all appropriate local au- prefer it because the additional data col- thorities and State and Federal agencies. lected can be used to verify expected load The schedule for the installation and im- reductions, evaluate effectiveness of control plementation of control measuresand their measures,and ultimately determine whether subsequentevaluations will include descrip- a Th4DL needs to be revised. tions of the types of controls, the expected pollutant reductions, and the time frame The PhasedApproach within which water quality standardswill be met and controls re-evaluated. Under the phased approach, the TMDL has LAs and WLAs calculated with margins Where no monitoring program exists, or of safety to meet water quality standards. where additional assessmentsare needed, it The allocations are based onestimateswhich is necessaryfor States to design and imple- use available data and information, but mon- ment a monitoring plan The objectives of itoring for collection of new data is required. the monitoring program should include as- The phased approach provides for further sessment of water quality standards attain- pollution reduction without waiting for new ment, verification of pollution source data collection and analysis. The margin of allocations, calibration or modification of se- safety developed for the TMDL under the lected models, calculation of dilutions and phased approach should reflect the ade- pollutant mass balances, and evaluation of quacy of data and the degree of uncertainty point and nonpoint source control effective- about the relationship between load alloca- ness. In their monitoring programs, States tions and receiving water quality. should include a description of data collection methodologies and quality assur- The Th4DL under the phased approach, ance/quality control procedures, a review of includes (1) WLAs that confirm existing lim- current discharger monitoring reports, and its or would lead to new limits for point be integrated with volunteer and coopera- sources and (2) IAs that confirm existing tive monitoring programs where possible. If controls or include implementing new con- properly designed and implemented, the trols for nonpoint sources. This TMDL re- monitoring program will result in a sufficient quires additional data to be collected to data base for assessment of water quality determine if the load reductions required by standard attainment and additional predic- the TMDL lead to attainment of water qual- tive modeling if necessary. ity standards. Data collection may also be required to more accurately determine as-

22 Approval of TMDLs by EPA ents or bioaccumulative pollutants could be expressed as the required average effluent TMDLS developed for all water quality- quality because the total loading of these limited waters are submitted to EPA for re- pollutants is of concern. On the other hand, view and approval. States are encouraged to an allocation for toxic pollutants should be coordinate with EPAprior to formal submis- expressedas a shorter-term requirement be- sion of their Th4DLs. Chapter 4 explains cause the concentration of these pollutants EPA and State responsibilities for the review is typi y of more concern than the total and approval process. loading.9 Implementation ofthe TMDL As a result of the 1987 Amendments to the Act, Individual Control Strategies(ICSs) After identifying the necessarypollutant were established under section 304(1)(1) for load reductions through the development of certain point source discharges of priority TMDLs and after approval by EPA, State toxic pollutants. ICSs consist of NPDES per- water quality management plans should be mit limits and schedules for achieving such updated and control measures im- limits, along with documentation showing plemented. 7’his section provides a brief re- that the control measures selected are ap- view of point and nonpoint source control propriate and adequate (i.e., fact sheets in- implementation. Additional guidance is cluding information on how water available and is referenced throughout the quality-based limits were developed, such as remainder of this chapter. total maximum daily loads and wasteload allocations). Point sources with approved NPDES Pnxessfor Point Somes ICSs are to be in compliance with those ICSs as soon as possible or in no case later than Both technology-based and water qual- three years from the establishment of the ity-based controls are implemented through ICS (typically by 1992 or 1993). the National Pollutant Discharge Elimina- tion System (NPDES) permitting process. The Clean Water Act (and correspond- Permit limits based on TMDLs are called ing State statutes) authorizes imposition of water quality-based limits. monitoring and data collection requirements on the owner or operator of a point Wasteload allocations establish the level source discharge. Requirements may in- of effluent quality necessaryto protect water clude ambient and biological assessments, quality in the receiving water and ensure toxicity reduction evaluations, in-plant mon- attainment of water quality standards. Once itoring, etc. Needed data collection may be allowable loadings have been developed initiated through a direct request under Sec- through WLAs for specific pollution tion 308 if there is a reasonable need for the sources,limits are incorporated into NPDES information for EPA to carry out the objec- permits. It is important to consider how the tives of the Clean Water Act The request WLA addressesvariability in effluent qual- must also meet the Paperwork Reduction ity. On the one hand, allocations for nutri- Act requirements. Information may also be

9 The reader is referred to the Permit Writer’s Guide to Water QuaIity-based Permitting for Toxic Pollutants (July, 1987) and the Technical Support Document for Water Quality-based Toxks Control (1985) for additional information oo deriving actual permit limits

23 Examples of Best Management Practices

AGRICULTURE SILVICULTURE Animal waste management Ground cover maintenance corlscrvation tillage Limiting disturbed areas contourfiuming Log removal techniques coIltour strip cropping Pesticide/herbicide management Cover crops Proper handling of haul roads Crop rotation Removal of debris Fertilizer management Riparian zone management Integrated pest management Road and skid trial management Livestock exclusion R e and pasture management MINING Sod-?I ased rotations Block-cut or haul-back Terraces Underdrains Water diversion CON!3TRUCl’ION Disturbed area limits MULTICATEGORY Nonve etative soil stabilization Buffer strips Runo f! detention/retention Detention/sedimentation basins Surface roughening Devices to encourage infiltration Grassedwatenvay URBAN Interception/diversion Flood storage Material ground cover Porous pavements Sediment traps Runoff detention/retention Streamside management zones Street cleaning Vegetative stabilization/mulching collected through permit reporting require- tices (BMPs) so that surf& water quality ments, or an administrative order. These objectives are met. These controls should be authorities can be used to collect data from based on LAs developed using the TMDL point sources when developing or assessing process. When establishing permits for the effectiveness of a TMDL point sources in the watershed, the record should show that in the caseof any credit for Permit requirements for data collection future nonpoint source reductions, (1) there should be established when longer term data is reasonableassurance that nonpoint source (e.g., for several seasons)are needed. The controls will be implemented and main- permit should include a statement that the tained or (2) that nonpoint source reductions permit can be modified or revoked and reis- are demonstrated through an effective mon- sued if the data indicate an exceedance of itoring program. Assurances may include State water quality standards. the application or utilization of local ordi- nances, grant conditions, or other enforce- State or Local Bvcess for Nonpoht Sources ment authorities. For example, it may be appropriate to provide that a permit may be In addition to permits for point sources, reopened for a WIA which requires more nonpoint source controls may be established stringent limits because attainment of non- by implementing Best Management Prac-

24 point source load allocation was not demon- appropriaff fs onitoring and evaluation ap strated. proaches. In order to fully addresswaterbodies that Assessmentofthe TMDL are impaired or threatened by nonpoint source pollution, States should implement Once control measures have been im- their nonpoint source management pro- plemented, the impaired waters should be grams and ensure adoption of control mea- assessedto determine if water quality stan- sures (best management practices) by all dards have been attained or are no longer contributors of nonpoint source pollution in threatened. The monitoring program used those watersheds. Example BMPs are listed to gather the data for this assessmentshould on the following page. State nonpoint be designed based on the specific pollution source management programs may include, problems or sources. For example, past ex- as appropriate, nonregulatory or regulatory perience has shown that severalyears of data programs for enforcement, technical assis- are necessary from agricultural nonpoint tance, financial assistance,education, train- source watershed projects to detect trends ing, technology transfer, and demonstration (i.e., improvements) in water quality. As a projects. result, long term monitoring efforts must be consistent over time in order to develop a It is difficult to ensure, a prioi that im- data base adequate for analysis of control plementing nonpoint source controls will actions. achieveexpected load reductions. Nonpoint source control measures may fail to achieve As shown in Figure 2, a TMDL that allo- projected pollution or chemical load reduc- cates loads and wasteloads to meet water tions due to inadequate selection of BMPs, quality standards must be established. If the inadequate design or implementation, or waterbody does achieve the applicable State lack of full participation by all co~tibuting water quality standards, the waterbody may sources of nonpoint pollution. States be removed from the 303(d) list of waters should describe nonpoint source load reduc- still needing TMDLS. If the water quality tions and establish a procedure for reviewing standards are not met, the TMDL and allo- and revising BMPs in TMDL documenta- cations of load and wasteloads must be mod- tion. The key objective for documenting ified. This modification should be based on load reduction goals and review procedures the additional data and information gath- is to establish a rational procedure for site- ered as required by the phased approach for specific evaluation of waterbodies with sig- developing a TMDL, where appropriate, as nificant nonpoint source pollution loads. part of routine monitoring activities, and States should consult additional nonpoint when assessing the waterbody for water source guidance for assistancein developing quality standards attainment.

10 USEPA. July, 1987. Setting Priorities The Key to Nonpoint Source Control. OW/OWRS, EPA. Washington, D.C. 11 USEPA. February, 1988. Draft Nonpoint Source Monitoring and Evaluation Guide. OW/NP!5Branch, Washington, D.C. 12 USEPA. September 19.1989. Nonpoint Source Monitoring and Reporting Requirements for Watershed Implementation Grants. OW/NPS Branch, Washington, DC.

25 CHAPTER4 - EPA AND STATERESPONSIBILITIES

Effective implementation of water qual- allocated, etc.). (See Appendix F for a gen- ity-based controls requires an integrated and eral EPA/State Agreement outline.) This cooperative partnership between EPA and agreement reduces the administrative bur- the States. The main responsibility for water den of the EPA review and approval process quality management resides with the States (see "TMDL Review and Approval,” p. 30). in the implementation of water quality standards, the administration of the NPDES pro- State Responsibilities gram (where the State has received EPA approval to do so), and the management of Identification of Water Quality-Limited Wa- nonpoint sources of pollution. When the ters Still Requiring TMDLs authority to implement nonpoint source control measures.is at the local level, inter- According to section 303(d) of the Clean agency and intergovernmental coordination Water Act and EPA water quality planning is especially important. The State should and management regulations, States are re- take the lead in facilitating and encouraging quired to identify waters that do not meet or the cooperation of local authorities. EPA is are not expected to meet water quality stan- responsible for ensuring that the Clean dards even after technology-based or other Water Act requirements are met through the required controls are in place. The enactment and enforcement of regulations, waterbodies are considered water quality- issuing program guidance, and providing limited and require TMDLs. technical assistance.The partnership developed between States and EPA should be When a State reports its list of 303(d) tailored to meet individual State needswhile waters, it is important that this list contain also meeting the requirements of the Clean only those water quality-limited waters that Water Act. This chapter describes specific still require TMDLs. Some water quality- State and EPA responsibilities in the part- limited waters may already have had suffi- nership. cient controls established for them and currently meet water quality standards. EPA/State Agreements These should not be on the list. In addition, the EPA regulations (40 CFR 130.7(b)) rec- EPA and the State should agree on the ognize the applicability of other appropriate process to develop TMDLs and this process pollution control requirements that can pro- should be consistent with EPA technical vide a more stringent level of control than guidance documents unless deviation from technology-based effluent limitations. the guidance is technically justified. An agreement should be written which de- When not listing a water quality-limited scribes technical and administrative proce- water a State must show that the controls dures (i.e., how background data are applied, specified by 40 CFR 130.7(b) (see p. 11) are how and which models are to be used, how enforceable, specific to the pollution prob- TMDLs are developed, how loads should be lems, and stringent enough to meet water

27 quality standards. If the controls are not yet develop their own user-defined codes by implemented, a State must provide a sched- specifyingadditional codes under each stan- ule for timely implementation. dard cause. The waters identified should be reported Similarly, a field exists in the Waterbody to EPA in the 305(b) water quality assess- Systemfor identifying the sourcesof the pol- ment reports due April 1 every even year. If lutants or conditions that are listed under a State prefers, the 303(d) list of waters can causesfor the nonattainment of uses in the be submitted separately at the same time. waterbody. Twelve general source catego- While initially it may be convenient to build ries are identified (see Appendix G) and uponthe reporting processesdescribed in include such things as industrial point Chapter2, the 303(d) list should be updated sources,municipal point sources, combined to reflect the latest monitoring and assess- sewer overflow, agriculture, and silviculture. ment data available. The User’s Guide also identifies 45 subcategories. Again the States may develop To facilitate the reporting of 303(d) wa- their own subcategoriesto describe causesof ters, the current section 305(b) Waterbody impairment of each water segment identi- System (WBS), a tool used for reporting fied with this system States should consult 305(b) information, contains fields already with the Guidelines for the Preparation of designated for this identification. The WBS the 305(b) Report (to be issued every odd providesa geographically based framework numbered year) and the Waterbody System for entering, documenting, and reporting in- User’s Guide for guidance in developing and formation on the quality of individual formatting their information waterbodies as they are defined by each State. The primary function of the WBS is to Documentation and Rationale for List- document water quality assessmentsand the ing - Along with the list of 303(d) waters water quality status of waterbodies, includ- submitted to EPA, adequate documentation ing causes and sources of use impairment. to support the listing of waters should be As a convenience to the States,the WBS has submitted. States have a number of readily been modified and will continue to be up- available sourcesof data and information to dated to include data fields on whether use when compiling their lists (see pages 12 TMDLs are still needed or are in place. The and 13). These sources, listed in Appendix WBS will also provide information to EPA C, should be used by States to develop their to assist in tracing the development of lists of 303(d) waters. However, additional TMDLs and overall program implementa- information may be required under certain tion. circumstances. Identification of Causes and Sourcesof Documentation for listing should also Pollution - When identifying the 303(d) wa- provide a description of the methodologies ters, the causes of the impairment also used to develop the list, a description of the should be identified for each segment listed. data and information used to identify water The Waterbody System has two separate quality-limited waters, and a rationale for fields that provide further information on a any decision to not use any one of the cate- particular water segment: “nonattainment gories listed in Appendix C. It is not ex- causes”and “nonattainment sources.” The pectedthat each and every waterbody listed “cause”field consistsof a list of constituents byState a be accompanied by the detailed or conditions that are causing nonattainment documentation as described. of water quality standards by a waterbody. The Waterbody System’sUsers Guide (third Adequate public participation should be edition, version 20) contains 23 standard a part of the listing process to make sure all causes(see Appendix G) and includes such water quality-limited waters are identified. parameters or categories aspesticides, met- This will support the State in defending its als, ammonia, and pathogens. States may list of such waters should the need to do so

28 arise, since, in its oversight responsibilities, used if they are technically defensible and EPA reservesthe right to ask for additional approved by EPA information re arding the State’sdecision to not list parti cuf ar waterbodies. For their TMDL submissions, States should include the proposed TMDLs, WLAs, LA, and the supporting information Identijication and Scheduling of Targeted that the Region will need to evaluate the Waterbodies State’s water quality analysis and determine Targeted waterbodies scheduled for whether to a prove or disapprove the sub- TMDL development over the next two years mitted TMD E . Regions and States should are to be identified and reported along with reach an agreement on the specific informa- the 303(d) list of waters that are submitted tion needed prior to their submission. For a during the 305(b) reporting process. These T’MDL developed under the phased ap- high priority TMDLs are to be based on proach, States should also submit to EPA a State develo ed priorities that consider the description of the controls to be established, severity of tli e impact and the uses of the the schedule for data collection, establish- water along with the other considerations ment of the control measures,assessment for described in Chapter 2. State submissions water uality standards attainment, and ad- which include the identification of 303(d) ditio n3 modeling if needed. targeted waters are subject to review and Quality assurance(QA) and uality con- approval or disapproval by EPA EPA will trol (QC) requirements should 3s 0 be met. expect the States to include ublic participa- Specific technical QA/QC is necessaxyin the tion in the development oP the list of h@ use of environmental data and models. priority targeted waterbodies. Tar eting However, when using models, such as waterbodies for control action should be a wasteload allocation models which involve key component of a State’s water quality “real” environmental data aswell asparamet- management and plannin programs. Wa- ric and mathematical relationships, model ters that are identified in i! tate annual work sensitivity studies can help establish the lev- plans will be compared to the targeted els of QA/QC required for specific data. For waterbodies and will be considered by EPA example, the allowable range of uncertainty during its review and approval of the annual in the data can be established through model work plans. sensitivity studies. This allowable range of uncertainty may indicate, for example, the 7MDL Development need for tight limits on precision for a particular pollutant ammeter. Ju#e~discus- Each State developsTMDLS for its water sion 1sprovide B elsewhere. uali -limited waters. The procedure for %4& roval by EPA is depicted in Fig- ure 3. T tates should use EPA’s technical cotltinuhg Plannakgmces support document and WLA technical guid- Each State is required to establish and ance series (see Appendix A) when develop- maintain a continuing planning recess ing TMDLS. Alternative approachescan be (CPP) as described in section 303(e7 of the 13 USEPA. September, 1980. Guidelines and Specifications for Preparing Quality Assurance Project Plans. QAMSM. Washington, D.C. 14 USEPA. December, 1980. Interim Guidelines and Specifications for Preparing Quality Assurance Plans. QAMS-O05/80.Wzshington, D.C. 15 USEPA. May, 1984. Guidance for Preparation of Combined WorWQuality Assurance Project Plans for l3wimnmed Monitoring. OWRS QA-1. Washington, D.C.

29 Clean Water Act. A State’s CPP contains, amo other items, a description of the pro- d& t the State uses to identify waters The State incorporates EPA approved nefding uI8fer quality-based controls; a pri- and EPAestablished TMDti into its Water o,~.y?gfgg~~~~~;~~~~ Quality Management Plan (WQMP). The Water Quality Management and Planning processused to receive public review of each TMDL Descri tionsmaybeasdetailedas regulation provides that when EPA ap the Regional o& ce and the State determine proves or establishesa TMDL under section 303(d), the TMDL is automati incorpo- is necessary to descrik each step of the P TMDL development process. ‘This process rated into the State’s WQMP.’ may be in&ded as art of the EPA/State Agreement for TMJJE development. Public NoticeandPardciphn In accordance with the Water Quality Management and Planning regulation and as

16 50FR1777,Janury11,1!385and40CFRI3O.

30 described in a State’s CPP, the TMDLs Reporring should be made available for public comment. States and involved local communi- State submission of a list of waters still ties should participate in determining which needing TMDLs and loads established is re- pollution sourcesshould bear the treatment quired by the Clean Water Act and the or control burden needed to reach allowable Water Quality Planning and Management loadings. By involving the local communi- regulations (40 CFR 130.7). These lists ties in decision making, EPA expects that a should complement EPA/State Agreements higher probability of successfulTMDL im- and the CPP, and be incorporated into the plementation will result. WQMP. States should submit the 303(d) lists either as part of or at the same time as In the identification of water quality-lim- the biennial section 305(b) reports. As part ited waterbodies, States need to involve the of this reporting requirement, States are ex- public as part of their review of all existing pected to identify those waters targeted for and readily available data and information. TMDL development in the next two years. This is especially true in such caseswhere a Targeted waterbodies are then scheduled for waterbody may be perceived as being at risk TMDL development through the annual due to new dischargers and changesin land work plan In addition, the pollutants or use. In such casesa waterbody’s water qual- conditions causingviolations of water quality ity may be “threatened” and therefore should standards and the point and nonpoint be given consideration for listing as a 303(d) sourcesof the pollution causing those condi- water. EPA expectsStates to include public tions should be identified for each water- participation in its development of high pri- body on the 303(d) list (see page 28). States ority targeted waterbodies that will proceed should consult the Section 305(b) Water- with TMDL development within two years body System’s Users Guide (August, 1989) following the listing process. to appropriately categorize sources and causesof pollutants. In the development of a TMDL, a State should issue a public notice offering an op- Other S’c@c Respnsibiliries portunity for a public hearing pertinent to the TMDL under review. It is recom- Other State responsibilities are to mended that this be done in conjunctionwith public notices and hearings on NPDBS per- l Ensure that needed environmental mits, construction of municipal wastewater data are provided to EPA, including treatment works, water quality standards re- appropriate assessmentdata; appro- visions, and Water Quality Management priate screening data; and all regula- Plan updates. Each notice should identify TMDLs as part of the subject matter.The tory data including data needed for State may wish to proceed to issuance of a approvals of the 303(d) lists and final TMDLwithout a hearing once notice is TMDLS, and given and there hasbeen little or no response by the public. o Ensure that appropriate quality assurance/quality control procedures Also, if a State determines that the water are used for all data used in State quality-based controls may be controversial, decision making and for all data re- the State should involve the EPA Regional ported to EPA including data re- office, as well as the public, early in the pro- ported by dischargers. cessand continue to involve them throughout the process.

31 EPA Resp~~ibilities 7iUDL ReviewandAppval

Review of 303(d) L&s Section 303(d) and the Water Quality Planning and Management regulation (40 Section 303(d) and the Water Quality CFR X+0.7(d)) requires EPA to review all Planning and Management Regulation (40 TMDLS for approval or disapproval. EPA CFR 130.7(d)) requires EPA to review and may tailor its review to what is reasonable approve or disapprove States’ lists of water and appropriate. For example, where a State quality-limited waters and the established hasclearlydescribeditsTMDLprocess inits pollutant loads. The lists are expected to be approved CPP (and EPA/State Agreement), submitted biennially and will be approved or EPA may conduct an indepth review of a disapproved based in part on the State’sdoc- sample of the State’s TMDLs to determine umentation and rationale for developing how well the State is implementing its ap- such lists as descriid under the State Re- proved process and conduct a less detailed sponribilifi6 section of this chapter. review of the remaining Th6DLs. This in- depth review of samplesof the State submis- K after reviewing the State lists and doc- sions, in conjunction with a less detailed umentation, EPA is satisfied that the State review of all other TMDLs submitted to has identified and appropriately listed all EPA by the State, will provide a reasonable impaired waters and those targeted for ac- basis for EPA approval or disapproval of tion, EPA will then approve the lists and individual TMDLS. The in-depth sample re- send a letter approving the submittal to the view may include TMDLS supporting major State. During this approval process, EPA construction projects and other major con- may request a State to provide additional trol measures. For those States that do not information if there is “good cause”to do so. have an approved process, Regions are ex- “Good cause”may include, but is not limited pected to conduct in-depth reviews of all to, more recent or accurate data; more accu- TMDIs. The Region’s review should also rate water quality modeling; flaws in the consider how well the States are following original analysis that led to the water being applicable technical guidance for establish- identified pursuant to 40 CFR 130.7; or ing TMDLS, WL&, and LAS. changes in conditions (e.g., elimination of discharges). EPA must, at a minimum, determine whether the State’sTMDLS are “established If the EPA disapproves (via a letter of at a level necessaryto implement the appli- disapproval to the State) a State’s list of wa- cable water quality standards with seasonal ters needing new or revised TMDLs and variations and a margin of safety that takes those targeted for action, the Region (work- into account any lack of knowledge concem- ing closely with the State) then identifies ing the relationship be?fen effluent limita- those waters where new or revised, and tar- tions and water quality. NoTMDLwillbe geted TMDLS are necessary. approved if it will result in a violation of water quality standards. If the State chooses not to develop the needed TMDLS for appropriate pollutants

17 CWA scuba 303(d)(l)

32 on a timely basis or, if the TMDLS are unac- TechnkulA.ktance and Thining ceptable to EPA, EPA has a role under the Act to develo48the TMDLs in cooperation EPA Headquarters and Regional offices with the State. This wU be done by focus- are available to provide technical assistance ing available EPA resources on the most and advice to tbe States in developing critical water quality problems. TMDLS. EPA Headquarters in coordination with the EPA Center for Exposure As- EPA must either approve or disapprove sessment Modeling (CEAM) provides for the State’s TMDL within 30 days after sub- training and assistanceon modeling. EPA mission by the State. Where a Th4DL is Headquarters also provides training and approved, EPA transmits a letter of such technical assistanceto users of the Water- approval. If EPA disapproves a State’s sub- body System (WBS). mission and the State does not agree to cor- rect the problems, then EPA shall, within 30 Guidance Documenrs and Repm days of the disapproval date, establish such TMDLS asnecessary to implement the water EPA Headquarters is responsible for de- quality standards. EPA solicits public com- veloping associatedprogram guidance, tecb- ment and after considering public comment nical support with assistance from EPA and malting appropriate revisions, EPA research laboratories, and producing the bi- transmits the revised TMDL to the State for ennial National Water Quality Inventory incorporation in the State’s Water Quality Report to Congress developed from the Management Plan19 EPA prefers to dis- State section 305(b) assessmentreports. charge this duty through a cooperative effort with the States.

ProgmmAUdi2.S EPA Headquarters is responsible for making sure the CWA mandates regarding EPA expectsto measureperformance on TMDLs are carried out, providing oversight the basis of environmental results and ad- of the Regional offices and the States,devel- ministrative goals by means of program au- oping program policy and guidance, support- dits. To achieve this performance ing the development of computer software measurement, EPA will periodically con- for calculating TMDLS, developing techni- duct audits of State water quality programs cal guidance documents, and providing tech- primarily through Regional visits to the nical training and assistance. Other States, review of State toxics control pro- responsibilities of EPA Headquarters are grams, and State action plan summaries of summarked on the next page. EPA’~Surface Water Toxics Control Pro- &ram* These program audits will serve to EPA &@bMl Respnstiiliries determine where additional training or other assistancemay be needed and to deter- The EPA Regional offices are responsi- mine implementation of program objectives. ble for assistingHeadquarters in developing policy and guidance, distributing policy and

18 SeeScott Decision: m 741 F.2d 992(7th Cir. 1984) 19 40 CFR l30.7(d) 2B 40 CFR 122,123, EQ Surface Water Toxk Control Program.

33 guidance totheStates,awardinggrantstothe wbere TMDLS are needed, the list of tar- States for developing and implementing geted waters, and specific TMDLS, WI& water quality-based controh and providing and LAS. The EPA Regional offices are also technical assistmce to the Sta& In addi- responsible for reporting on State im- tion, the Regional offices are responsible for plementation to Headquarters. Other re- revicwingandapprovingor disapprovingthe sponsibilities of EPA Regional offices are following: each State’s TMDL process, the summarized below. annual work program, the list of waters

Other EPA Headquarters Responsibiites

l Prepare pi&ace and ensure that approphte technical training and technical assistanceis available for monitoring, water quality a&y& and data reporting.

l Performnathalasx%nwU and wahmte the national water quality effects of CWA programs.

l Make nathal data systemsmore usdid for national, regional, and State mecs by upgrading and mxdhkhg the uidng systemsand dcvek+g interactive data retrieval and analy& mtchhnisms for line- QatinucsupportdthRiverRcachandIndustrialFaciiityDishrgcfh. l Ensurethat rppropriattq~~murct/qualitycontrolproccduFcsueusedioall;naticMaldata odlactioae&rcsandp~~~orysnpportforDItioiralscudicsofpolllurrnurequiringspecial

l Prepare Headquarters budget rqucsts, and in axwhation with the Regions, prepare requests for Regional and State water quality moniaoring and analy& programs.

l Peer review major agwxy program acdvities invohing water monitoring and consult with other program offices on water monitoring activities.

Other EPA Regional Responsibiities

l Easurc that the appropriate regulatory monitoring is performed by the Statesand discharges needed for developing and implcxnca~ water quality-based controls and identifying needed nonpoint source controls. This includes data rquircd to identify watersneedingwater quality-based contrds, data needed to dcvclop contrds, and data Ix&cd to assessthe eff~c5s of controls. 0 Provide technical assistanceand training to the Stateson watu quality monitoring and analyses. For work invdvirq toxic+ provide asdance in both the pollutant sp66c and the biomonitoring approaches and w&ok effluent toxicity. 0 Ensure that appropriate quality assurauccYqualitycontrol procedures are used for all Regional and State wattrqualitydataandforalldatausedinRegionaldedsion~includingdatareportedbypumitttes.

l Perform Regio~I water quahy assessmentsphmariiy basedon State data as needed to prepare Environ- mental Mauagcmcnt Reports. l Ensure that Regional data systemsare cotnpatible with and do not unnecessarily duplicate national data

34 APPENDIX A- RELATIONSHIP TO OTHER GUIDANCE

Monitoring Guidance controls. Current guidance 2324 describes the factors to be considered in designing and The Clean Water Act specifies that implementing cooperative and volunteer States and Interstate Agencies, in coopera- monitoring projects so that specific provis- tion with EPA, establish water quality mon- ions are made for the collection and analysis itoring systems necessary to review and of scientifically valid water quality data, and revise water quality standards, calculate so that the State water pollution control TMDLs, assesscompliance with permits, agencieshave the necessaryinformation for and report on conditions and trends in ambi- final review and approval of all projects. ent waters. EPA’s current program guid- ance21 discusses the programmatic Cooperative monitoring projects can relationships of monitoring as an informa- serve the same usefulnessas other monitor- tion collection tool for many program needs. ing studies; however, they also provide a NPS pollution concerns are discussed in mechanism to maximize limited resources. draft guidance along with some means to In addition to “tapping” additional resources monitor and evaluate NPSs.22 Revised for monitoring, there are other incentives for Monitoring Program Guidance is planned Statesand the regulated community to coop- for FY 1991. erate, such as having more site-specific data from which to develop site-specific, scientif- Cooperative Monitoring/Citizen ically-based water quality criteria. Volunteer Monitoring Guidance Citizen volunteer monitoring involves identifying sourcesof pollution, tracking the Cooperative monitoring involves shared progress of protection and restoration pro- efforts by individuals or groups in assessing jects, and/or reporting special events such as water quality conditions. Cooperative ar- fish kills and storm damage. For more infor- rangements are encouraged by the Clean mation on citizen monitoring programs, con- Water Act as referenced in section 104. Co- tact the EPA Office of Water Regulations operative monitoring projects require care- ful planning and strong management 21 USEPA. 1985. Guidance for State Water Monitoring and WasteloadAllocation Programs. OW/OWRS, EPA 440/4-85-031.Washington, D. C. 22 USEPA. 1987. Draft Nonpoint Source Monitoring and Evaluation Guide. OW/OWRS, EPA. Washington, D. C. 23 USEPA. 1984. Planning and Managing Cooperative Monitoring Projects. OW/OWRS, EPA 440/4-84-018.Washington, D. C. 24 USEPA. 1990. Volunteer Water Monitoring: A Guide for State Managers. OW, EPA 440/4-90-010. Washington, D. C.

35 and Standards (OWRS), Monitoring Branch Technical Guidance Manuals for at 202/382-7056. Performing Wasteload Allocations

Wasteload Allocation Technical Guid- Book Title I. General Guidance ance II. Streams and Rivers - Biochemical Oxygen Demand/Dissolved Technical guidance manuals prepared by oxygen EPA explain how to prepare wasteload allo- - Nutrient/Eutrophication cations (WLAs). These manuals are listed at - Toxic Substances the right. Those available can be obtained - Simplified Analytical Method for Deter- from the OWRS Monitoring Branch at mining NPDES Effluent Limitations for 202/382-7056. POTWs Discharging into Low-Flow Streams III. Estuaries Technical Support Document for - Estuaries and Wasteload Allocation Water Quality-based Toxics Control Models - Application of Estuaries Waste Load Al- location Models The Technical Support Document - Use of Mixing Zone Models in Estuarine (TSD) for Water Quality-based Toxics Con- Waste Load Allocations* trol 25 presents recommendations to regula- - Critical Review of Estuarine Waste Load tory authorities when they are faced with the Allocation Modeling task of controlling the discharge of toxic pol- IV. Lakes and Impoundments lutants to the nation’s waters. Included in - Biochemical Oxygen Demand/Dissolved Oxygen this document are detailed discussions on - Nutrient/Eutrophication EPA’s recommended criteria for whole ef- - Toxic Substances fluent toxicity, a screening analysis method- V. Technical Support Document for ology for effluent characterization, human Water Quality-Based Toxics Control health risk assessment, the use of exposure VI. Design Locations assessments for wasteload allocations, and - Design Flow the development of permit requirements - Design Temperature, pH, Hardness, and and compliance monitoring. The TSD provides guidance for assessing and regulating VII. Permit Averaging the discharge of toxic substances. It supports VIII. Screening Manual EPA’s initiative to control toxic pollution by - Biochemical Oxygen Demand/Dissolved involving the application of biological and Oxygen chemical assessment techniques and pro- - Toxic Organics - Toxic Metals poses solutions to complex and site-specific - Nutrient/Eutrophication pollution problems. Information on this IX. Innovative Wasteload Allocations* document can be obtained from EPA’s Water Quality and Industrial Permits * not yet available Branch at 202/475-9537.

25 USEPA. 1985. Technical Support Document for Water Quality-based Toxics Control. OW/OWRS and OWEP, EPA 440/4-85 Washington, D.C. A revised draft (April 23,1990) is available and will replace the 1985 Guidance once it is finalized.

36 Permit W&KS Guidance toxicity-based assessment procedures and pollutant-specific assessment procedures. The Permit Writer’s Guide to Water Roth procedures are needed to enforce State Qual&-based Permitting For Toxic Pollu- water quality standards. tants provides State and Federal NPDES permit writers and water quality manage- Nonpoint Source Guidance ment staff with a reference on water quality- based permit issuance procedures. This Section 319 of the Clean Water Act es- guidance presents fundamental concepts tablishes direction and financial assistance and procedures in detail and refers to more for the implementatip of State NPS pro- advanced toxics control procedures, such as grams. NPS guidance encouragesStates to dynamic modeling of complex discharge sit- develop State Clean Water Strategies for uations, which may not yet be incorporated integrating and unifying the States’ approach into many State programs. The guidance to water quality protection and clean-up. explains aspects of water quality-based tox- Three steps are identified for this process: its control in terms of what a permit writer comprehensive assessment of impaired or currently needs to know to issue a water threatened waters, targeted protection of quality-based toxics control NPDES permit. waters, and development of strategic management plans. States are to develop NPS The NPDES permits program is now fo- programs which build upon related pro- cused on control of toxic pollutants and the grams (e.g., Clean Lakes, National Estuar- guidance document is directed at supporting ies, Stormwater Permits, Ground Water, these control efforts. Water quality prob- Toxics Controls, State Revolving Funds, and lems related to conventional pohutants, such Wetlands) and to coordinate their efforts as those associatedwith point source contri- with other federal agencies. butions to oxygen depletion, are addressed in other guidance documents. The 1987 amendments to the CWA include provisions to encourage States to ac- The Permit Writer’s guide addresses celerate efforts to control nonpoint source three areas of toxic effects: aquatic life, pollution. The amendments require States human health, and the bioaccumulation of to prepare a Nonpoint Source Assessment specific chemicals. Each effect must be dealt Report and a 4-year Management Program. with on an individual basis using available Funds are provided to assist the States in data and tools. This guidance also cata- implementing these programs. Information logues the principal procedures and tools on this guidance can be obtained from EPA’s available. Nonpoint Source Control Branch at 202082-7085. The guidance supports an integrated tox- its control strategy using both whole effluent

26 USEPA. 1987. Permit Writer’s Guide to Water @ml@-based Permitting for Toxic Pollutants. OW/OWEP, EPA 440&8%005. Washington, D.C. 27 USEPA. 1987. Nonpoint Source Guidance. OW/OWRS, EPA. Washington, D.C.

37 APPENDIX B - SUPPORTING PROGRAMS

EPA Water Quality Criteria and sider the use and value of State waters for Standards public water supplies, propagation of fish and wildlife, recreation, agriculture and in- The water quality standards program, as dustrial purposes, and navigation. envisioned in Section 303(c) of the Clean Water Act, is a joint effort between the In the current Water Quality Standards States and EPA The States have primary regulation, section 131.11encourages States responsibility for setting reviewing revising to adopt both numeric and narrative criteria. and enforcing water quality standards. EPA Criteria protect both short-term (acute ) and develops regulations, policies, and guidance long-term (chronic) effects. Numeric cri- to help States implement the program and teria are important where the causeof toxic- overseesStates activities to ensure that State ity is known or for protection against adopted standards are consistent with the pollutants with potential human health im- requirements of the Act and the implement- pacts or bioaccumulation potential. Nu- ing Water Quality Standards regulation (40 meric water quality criteria may also be the CFR Part 131). EPA has authority to review best way to address nonpoint source pollu- and approve or disapprove State standards tion problems. Narrative criteria can be the and, where necessary,to promulgate Federal basisfor limiting toxicity in waste discharges water quality standards. where a specific pollutant can be identified as causing or contributing to the toxicity but A water quality standard defines the there are no numeric criteria in the State water quality goals of a waterbody, or portion standards,or where toxicity cannot be traced thereof, by designating the use or usesto be to a particular pollutant. Whole effluent tox- made of the water, by setting criteria neces- icity (WET) testing is also appropriate for sary to protect the uses, and by preventing discharges containing multiple pollutants degradation of water quality through anti- becauseWET testing provides a method for degradation provisions. States adopt water evaluating synergistic and antagonistic ef- quality standards to protect public health or fects on aquatic life. Biological criteria pro- welfare, enhance the quality of water, and vide a means to measure aquatic community serve the purposes of the Clean Water Act. structure and function. EPA considers a “Serve the purposes of the Act” (as defined combination approach of narrative, nu- in Sections 101(a), 101(a)(2), and 303(c) of meric, and biological criteria necessary to the Act) means that water quality standards protect beneficial uses fully from the broad should: 1) include provisions for restoring range of point and nonpoint sources of pol- and maintaining chemical, physical, and bio- lution. logical integrity of State waters, 2) provide, wherever attainable, water quality for the In addition, the Clean Water Act in Sec- protection and propagation of fish, shellfish, tion 303(c)(2)(B) requires States to adopt and wildlife and recreation in and on the numeric criteria for priority toxic pollutants water (“fishable/swimmable”), and 3) con- for which EPA has published criteria guid-

38 ancewhen the discharge or presenceof these Section 305(b) -- Water Quality pollutants could reasonably be expected to Assessment interfere with the designated usesin affected waters. States may adopt criteria with State- Section 305(b)28establishes a processfor wide application or site-specific criteria. reporting information about the quality of the nation’s water resources to EPA and EPA’s regulation requires each State to Congress. Each State, Territory, and Inter- adopt, as part of its water quality standards, state Commission develops a program to an antidegradation policy consistent with 30 monitor the quality of its surface and ground CFR 131.12. The regulation also requires waters and report the current status of water each State to have implementation methods quality biennially to EPA This information for its antidegradation policies, i.e., decision is compiled into a biennial report to Con- criteria for assessingactivities that may im- gress. The 305(b) report allows EPA to: pact the integrity of a waterbody. Activities covered by the antidegradation policy and • Determine the status of water qual- implementation methods include both point and nonpoint sources of pollution. Section ity. 131.12effectively sets out a three-tiered approach for the protection of water quality. • Identity water quality problems and “Tier 1” (40 CFR 131.12 (a)(1)) of anti- trends. degradation maintains and protects existing uses and the water quality necessaryto pro- • Evaluate the causes of poor water tect these uses. “Tier II” (section quality and the relative contributions 131.12(a)(2)) protects the water quality in of pollution sources. waters whose quality is better than that necessary to protect “fishable/swimmable” uses • Report on the activities underway to of the waterbody. Outstanding national assessand restore water quality. resource waters (ONRWs) are provided the highest level of protection under the anti- • Determine the effectiveness of con- degradation policy (‘Tier III”). trol programs. States may, at their discretion, adopt policies in their standards affecting the applica- • Ensure that pollution control pro- tion and implementation of standards. EPA grams are focused on achieving envi- specifically recognizes mixing zones, vari- ronmental results in an efficient ances,low flow exemptions, and schedulesof manner. compliance for water quality-based permit limits. Guidance on these subjects is avail- • Determine the workload remaining able from EPA’s Office of Water Regula- in restoring waters with poor quality tions and Standards, Criteria and Standards and protecting threatened waters. Division. • Use information from the lists of waters developed under sections 304(l)

28 USEPA. 1989. Guidelines for the Preparation of the 1990State Water Quality Assessment(section 305(b) Report). OW/OWRS. Washington, D. C.

39 and 319 and continue to maintain and ters that still do not meet applicable water update the statutorily-required lists quality standards. The short list (section of waters identified under sections 304(l)(l)(B)) is a list of State waters that are 303(d) and 314. not expxted to meet applicable standards after technology-based controls have been For each assessedwaterbody, informa- met, due entirely or substantially to dis- tion is provided on the water quality-limited chargeof toxic pollutants from point sources. status, use nonattainment causes and A fourth list is the list of point source dis- sources, cause magnitude, and source mag- chargersof priority toxic pollutants to waters nitude. Much of the information from the listed under section 304(l). 305(b) assessmentsprovide useful information for developing lists of water quality-lim- Se&n 319 - Nonpoint Source ited segments asked for in section 303(d). p%Pm Section 304fl) -Impaired Waters One key initiative of the 1987 Water Quality Act Amendments to the Clean Section 304(UB required lists of im- Water Act was the addition of section 319 paired waters and sourcesto be submitted to which establisheda national program to con- EPA as a “one time” effort. These lists of trol nonpoint source pollution. Under this waters (known as the short, long, and mini program, Statesare askedto assesstheir NPS lists) provide three types of designations for pollution problems and submit that assess- impaired waters and source impacts. The ment to EPA These assessmentsinclude a mini list (section 304(l)(l)(A)(i)) is a list of list of “navigable waters within the State waters that the State does not expect to which, without additional action to control achieve numeric water quality standards for nonpoint sources of pollution, cannot rea- priority pollutants (section 307(a)) after sonably be expected to attain or maintain technology-based requirements have been applicable water quality standards or the met, due to point or nonpoint source pollu- goals and requirements of this Act.” Other tion. The long list (section 304(1)(l)(A)(ii)) paragraphsof section 3 19require the identi- is a comprehensive list of waters that are not fication of categories and subcategories of meeting the fishable and swimmable goals of NPS pollution which contribute to the iden- the Act whether due to toxicity or other im- tification of impaired waters; descriptions of pairments; point or nonpoint sources; or the procedures for identifying and im- toxic, conventional. or nonconventional pol- plementing BMPs; control measuresfor re- lutants. A waterbody which meets its desig- ducing NPS pollution; and descriptions of nated use criteria and does not meet State and local programs used to abate NPS fishable/swimmable criteria would be listed pollution. Based upon the assessments, on the section 304(l) long list but not neces- State nonpoint source management pro- sarily on the section 303(d) list of waters grams are prepared and presented to EPA needing TMDLs. It would be appropriate for approval. Once these programs are ap- for a State to use the information on all proved, grant funds are made available for waters from its long lists and apply these data the implementation of the program. in developing the section 303(d) list of wa- 29 USEPA. March, 1988. Final Guidance for Implementation of Requirements under section 304(l) of the Clean Water Act as Amended. OWRS and OWEP. Washington, D.C.

40 Section 319 assessmentsidentify waters communicate its lessons to the more than with impairments due primarily to NPSs for 150 estuaries located along our coasts. which TMDLs (including LAS) may need to be developed to establish protection of For approved estuaries, the Administra- water quality. States are encouraged to use tor convenes management conferences, a these tools where appropriate to achieve or grouping of interested Federal, Regional, protect beneficial uses of the water. State, and local governments, affected indus- tries, scientific and academic institutions, Section 314 -- C&fan Lakes Progrrrm and citizen organizations. Management conferences strive for an open, consensus- Historically, the Clean Lakes Program building approach to defining program goals has been active in awarding grants for the and objectives, identijing problems to ad- study and restoration of publicly-owned dress, and designing pollution preven- lakes. Under this program, states are en- tion/control and resource management couraged to develop integrated water quality strategies to meet each objective. Manage- strategies that include lake and reservoir ment conferencesare required to create and management, restoration, and protection ac- begin implementation of a Comprehensive tivities. EPA provides financial assistanceas Conservation and Management Plan available; however, greater emphasis is now (CCMP) designed to protect and restore the on developing technical support material estuary. (e.g., a Lake and Reservoir Restoration Guidance Manual). Monitoring Program

Section 320 -- Ndional Estuary Ambient water quality monitoring is a data gathering tool used for almost all water Progmm quality assessment. Monitoring programs serve to identify waters needing TMDLS, Authorized by Congressin 1985,and for- quantify loads, verify models, and evaluate mally established in 1987 by amendments to effectiveness of water quality controls (in- the Clean Water Act, the National Estuary cluding BMP effectiveness). Once TMDLs Program (NEP) builds upon the lessons of havebeen established for a given waterbody, the ChesapeakeBay, Great Lakes, and other follow-up monitoring is recommended to earlier programs in a geographic, basin-wide document improvement or lack of improve- approach to environmental management. ment. Since the TMDL process is iterative, The EPA Administrator selectsestuaries for monitoring data can provide the information NEP participation through State governors’ for updating and revising current TMDLs. nominations. To be selected estuaries must Ambient monitoring is used for setting per- demonstrate a likelihood of successand evi- mit conditions, compliance, and enforce- dence of institutional, &xmcial, and political ment, and detecting new problems and commitment to solve their problems. trends. Among the environmental problems addressed in the NEP estuaries are the loss of Emnt Limitation Guidelines and aquatic habitats, toxic contamination of es- StUndatdr tuarine sediments, increases in nutrient levels, bacterial contamination, and hypoxia. As EPA develops effluent limitation guide- methods for assessingand successfullyman- lines and new source performance standards aging these estuaries are developed, this na- for industrial dischargers. These are uni- tional demonstration program aims to form technology-basedlimitations for indus-

41 trial facilities discharging directly into the ters and on the sources of such pollutants. nation’s waters. EPA also developspretreat- Authority for issuing NPDES permits is g- ment standardsfor those facilities which dis- tablished under section 402 of the CWA charge into Publicly Owned Treatment Works (POTWs). Point sourcesare generally divided into two types: “industrial” and “municipal.” Na- During the effluent guidelines promul- tionwide, there are approximately 50,000in- gation process,EPA develops a profile of the dustrial sources which include commercial industry to determine pollutant loadings of and manufacturing facilities. Municipal untreated wastewater for which effluent lim- sources, also known as POTWs, number itation guidelines are being developed. Pol- about 15,700nationwide. Wastewater from lutants of concern and technologies for municipal sources results from domestic treating them are then identified. EPA then wastewater discharged to POT% as well as prepares estimates of total investment, oper- the “indirect” discharge of industrial wastes ation and maintenance costs of complying to sewers. with each technology option, and evaluates the regulatory options, both technically and Section 304(1)(1)(D) required, at a min- economically, to select a technology as the imum, the development of individual control basis for the guidelines. strategies (ICSs) for point source discharges of priority toxic pollutants to waters identi- Effluent limitations, guidelines, and fied on the short list. (The short list is com- standards are established for three types of posed of State waters for which applicable industrial pollutants: conventional, toxic, section 307(a) priority pollutant standards and nonconventional. Effluent guidelines are not expected to be achieved after tech- generally limit the amount of pollutant that nology-based controls have been met, due can be discharged at an individual facility. entirely or substantially to point sources.) The numerical limits in the guidelines are An ICS consists of NPDES permit limita- determined using industry-specific produc- tions and schedulesfor achieving established tion data and the treatability data for the limitations, along with other documentation selected technology. to demonstrate that the con ls selected are appropriate and adequate. ‘Ip NPVES Permits and Individual Control Stmtegies Marine and Estuarine W&em All discrete sources of wastewater must In January 1990, EPA published its Na- obtain a National Pollutant Discharge Elim- tional Coastal and Marine Policy, which es- ination System (NPDES) permit that regu- tablishes EPA’s goals for coastal and marine lates the facility’s discharge of pollutants. protection. They include: The approach to controling and eliminating water pollution is focused on the pollutants l Recover full use of the nation’s determined to be harmful to receiving wa- shores,beaches, and water.

30 USEPA. 1989. Overview of selectedEPA Regulations and Guidance Affecting POTW Management. OW/OMPC, EPA 440/69-89AN8.Washington, D.C. (Hotline: 800-424-9346) 31 USEPA. 1987. Permit Writer’s Guide to Water Quality-based Permining for Toxic Pollutants. OW/OWEP, EPA 440/4-87-005.Washington, D.C.

42 Restore the nation’s shell fisheries charge accounted for as much as 90% or and salt-water fisheries. more of stream flow in humid regions. Therefore, the potential pollutant contribu- . . . Mmmze the use of coastal and ma- tions from ground water to surface waters rine water for waste disposal. should be investigated when developing TMDLS. Additional information is avail- Improve and expand coastal science. able from the EPA Office of Ground Water Protection. Support international efforts to protect coastal and marine resources. CERCLA

EPA’s programs to protect ocean and The Comprehensive Environmental Re- coastal waters and the Great Lalres from sponse, Compensation, and Liability Act nutrient and toxic pollutants emanating from (CERCLA) or “Superfund” provides broad point and nonpoint sources are im- federal authority to respond directly to re- plemented under the Clean Water Act and leases or threatened releases of hazardous the Marine Protection, Research, and Sanc- substances. This law also provides for the tuaries Act (Ocean Dumping Act). cleanup of inactive or abandoned hazardous waste sites. Under CERCLA, EPA assesses Marine and estuarine waters are, in many the nature and extent of contamination at a cases,the ultimate sink for pohtants which site, determines the public health and envi- emanate from upland sources. Estuarine ronmental threats posed by a site, analyzes and marine waters are particularly complex the potential cleanup alternatives, and takes and it is often d.i&ult to predict Pollutant action to clean up the site. In instances fate and transport. To addressthe increased where a CERCLA site has impact on a complexity and effect on aquatic life, water nearby waterbody, the level of cleanup quality management efforts must increase needed to maintain water quality standards accordingly. TMDLS can be a useful tool for of surface waters should have a direct rela- management of marine and estuarine wa- tionship to the TMDL for the affected sur- ters. Technical guidance is currently &ing face waters. As part of the CERCLA revised to support estuarine modeling. process, all “applicable or relevant and appropriate requirements” of statutes such as the CWA must be followed. Load alloca- Groundwuter tions developed pursuant to section 303(d) may, in appropriate circumstances, be “ap- Contaminated ground water dischargeto plicable or relevant and appropriate.” surface water may be a source of contaminants in water quality-limited surfacewaters. PO’TWs that discharge CERCLA haz- While ground water and surface water are ardous substancesin effluent at levels that often treated asseparate systems,they are in equal or exceed NPDES permit limitations, reality highly interdependent components of or for which no specific limitations exist, or the hydrologic cycle. Subsurface interac- in spills or other releases,may be subject to tions with surface waters occur in a variety of the notification requirements and liability ways. In several studies, ground water dis- provisions under CERCLA. In addition, 32 USEPA. Technical Guidance Manual for Performing WasteloadAIbcations, Book III - Estuaries.

43 POTWs that disposed of sludge in im- 535-0202), which amended CERCLA, also poundments or ladills that are Superfund established in Title III a new program to sites may be required to pay for cleanup of increase the public’s knowledge of and ac- those sites. At times, POTWs may be re- cessto information on the presence of hax- quested to accept wastewaters from Super- ardous chemicals in their communities and fund cleanup activities. If discharge of releasesof these chemicals into the environ- CERCLA wastewaters to a POTW is ment. Title III (Community Right to Know deemed appropriate, the discharger must Program) requires facilities to notify State ensure compliance with substantive and pro- and local officials if they have extremely haz- cedural requirements of the national pre- ardous substancespresent at their facilities treatment program and all local in amounts exceeding certain “threshold pretreatment regulations before discharging planning quantities.” If appropriate, the fa- wastewater to the POTW. cility must also provide material safety data sheets on hazardous chemicals stored at The provisions of CERCLA extend well their facilities, or lists of chemicals for which beyond the regulation of POTW discharges. these data sheetsare maintained, and report The most common types of Superfund sites annually on the inventory of these chemicals governed by CERCLA include abandoned used at their facility. The law may also re- hazardous waste sites and inactive mines, quire facilities to submit information each many of which do not discharge to POTWs. year on the amount of toxic chemicals re- leased by the facilities to all media (air, water, and land), if they fall within Standards Industrial Classification Codes 20 to 39 and The Superfund Amendments and meet certain threshold limits. Reauthorization Act (SARA Hotline 80@

44 APPENDIX C - SCREENINGCATEGORIES

This list of screening categories is based on categories promulgated as the minimum data set a State should consider when developing their list of impaired waters pursuant to section 304(l) of the Clean Water Act. When developing lists pursuant to this guidance and to meet the requirements of section 303(d), a State should, at a minimum, use these categories to identify their water quality-limited waters. Statesshould also consider additional information, such asTRI data, streamflow information collected by USGS, locally available data, and public comments on proposed 303(d) lists. 1. Waters where fishing or shellfish bans industry in Appendix A of 40 CFR Part and/or advisories are currently in effect 122. or are anticipated. 8. Waters for which effluent toxicity test 2. Waters where there have been repeated results indicate possible or actual ex- fishkills or where abnormalities (cancers, ceedances of State water quality stan- lesions, tumors, etc.) havebeen observed dards, including narrative “free from” in fish or other aquatic life during the last water quality criteria or EPA water qual- ten years. ity criteria where State criteria are not available. 3. Waters where there are restrictions on water sports or recreational contact. 9. Waters with primary industrial major dis- chargerswhere dilution analysesindicate 4. Waters identified by the State in its most exceedances of State narrative or nu- recent State section 305(b) report as ei- meric water quality criteria (or EPA ther “partially achieving” or “not achieving” designated uses. water quality criteria where state standards are not available) for toxic pollu- 5. Waters listed under sections 304(l) and tants, ammonia, or chlorine. These 319 of the CWA. dilution analysesmust be based on estimates of discharge levels derived from Waters identified by the State as priority 6. effluent guidelines development docu- waterbodies. (State Water Quality Man- ments, NPDES permits or permit appli- agement plans often include priority cation data (e.g., Form 2C), Discharge waterbody lists which are those waters that most need water pollution control Monitoring Reports (DMRs), or other available information. decisions to achieve water quality standards or goals.) 10. Waters with POTW dischargers requiring local pretreatment programs where 7. Waters where ambient data indicate po- dilution analysesindicate exceedancesof tential or actual exceedances of water State water quality criteria (or EPA quality criteria due to toxic pollutants water quality criteria where State water from an industry classified as a primary quality criteria are not available) for

45 toxic pollutants, ammonia, or chlorine. lic interest groups, or universities. These These dilution analyses must be based organizations and groups should be ac- upon data from NPDES permits or per- tively solicited for research they may be mit applications (e.g., Form 2C), Dis- conducting or reporting. For example, charge Monitoring Reports (DMRs), or university researchers,the United States other available information. Department of Agriculture, the National Oceanic and Atmospheric Administra- 11. Waters with facilities not included in the tion, the United States Geological Sur- previous two categories such as major vey, and the United States Fish and POTWs, and industrial minor discharg- Wildlife Serviceare good sourcesof field ers where dilution analyses indicate ex- data and research. ceedancesof numeric or narrative State water quality criteria (or EPA water 14. Waters identified by the State as im- quality criteria where State water quality paired in its most recent Clean Lake As- criteria are not available) for toxic pollu- sessmentsconducted under section 314 tants, ammonia, or chlorine. These dilu- of the Clean Water Act. tion analyses must be based upon 15. Waters identified as impaired by non- estimates of discharge levels derived . point sourcesin America’s. Clean Water: from effluent guideline development The States' Nonpoint Source Assess- documents, NPDES permits or permit ments 1985 (Associationof State and In- application data, Discharge Monitoring terstate Water Pollution Control Reports (DMRs), or other available in- Administrators (ASIWPCA)) or waters formation. identified as impaired or threatened in a 12. Waters classified for uses that will not nonpoint source assessment submitted support the “fishable/swimmable” goals by the State to EPA under section 319 of of the Clean Water Act. the Clean Water Act. 13. Waters where ambient toxicity or ad- 16. Surface waters impaired by pollutants verse water quality conditions have been from hazardous waste sites on the Na- reported by local, State, EPA, or other tional Priority List prepared under sec- Federal agencies,the private sector, pub- tion 105(8)(A) of CERCLA, APPENDIX D- SELECTED TECHNICAL CONSIDERATIONS

Design Conditions Often conditions of best management practices may be specified for factors other When developing a TMDL, design con- than physical conditions. For example, as- ditions are those critical conditions that must sumptions about cropping patterns, logging be specified in order to determine attain- rates, or grazing practices may be necessary ment of water quality standards. In specify- to determine the pollution loading estimates ing conditions in the waterbody, an attempt of a waterbody. Design conditions are less is made to use a reasonable “worst case” standardized for these factors and a reason- condition. For example, stream analysis able worst casecondition often must be de- often uses a low flow (e.g., 7-day low flow, veloped on a case-by-casebasis. once in 10-yearscommonly known as7Q10 or biologically-based 4-day 3-year flows) high In general for point sources,continuous temperature design condition. discharges present the greatest stressunder low flow, dry weather conditions. For pollu- In situations where nonpoint source tants transported in runoff, critical condi- loadings at wet weather flow conditions are tions will be rainfall-related, but may occur more significant than the point source load- under a variety of flow conditions. For NPSs ings, the use of low flow-related design con- or intermittent point sources,generally, high ditions is inappropriate. Wet weather flow flow, wet weather conditions need to be eval- conditions may be appropriate for analysisof uated. For carcinogenic pollutants, har- nonpoint and intermittent point source dis- monic mean flows may be appropriate. chargessuch as storm sewers. Other factors Additional details for selecting design con- such as rainfall intensity and duration, time ditions are provided in technical guidance. since previous rainfall, pollutant accumula- tion rates, and stream flow previous to rain- Mathematical Models fall should be considered in selecting design conditions for nonpoint source analysis. In When the analyst is calculating a numer- some instances (e.g., carcinogenic pollu- ical TMDL, several mathematical models tants), it is appropriate to use the harmonic can be used to evaluate alternative pollutant mean flow to estimate loading capacity. loading scenarios. Models supported by the EPA Center for Exposure and Assessment Modeling (CEAM) are summarized in Ap-

33 USEPA. 1985.Technical Support Document for Water Quality-based Toxics Control OW/OWEP and OWRS, EPA 440/4-85-032.Washington, D.C. A revised draft (April 23, 1990)is available and will replace the 1985Guidance when finalized.

47 pendix E. While it is beyond the scopeof this lumped single-catchment models are guidance to provide a detailed rationale for more appropriate for homogeneous model selection, the following briefly pres- or less complex situations. ents a discussion on model characteristics and selection. • Specific constituents and processes simulated-Models vary in the types Model characteristics of constituents and processes simulated and in the complexity of the Models can be characterized in numerous ways such as by their data requirements, formulations used to represent each ease of application, etc. This section sum- process. For example, simple DO marizes models based on four categories: models include only reaeration and temporal characteristics, spatial characteris- BOD decay while more complex tics, specific constituents and process simu- models include other processessuch lated, and transport processes. as nitrification, photosynthesis, and algal respiration. • Temporal characteristics - This includes whether the model is steady- • Transport processes- These include state (inputs and outputs constant advection, dispersion, runoff, inter- over time), time-averaged (for exam- flow, ground water interactions, and ple, tidally-averaged), or dynamic. If the effects of stratification on these the model is dynamic, an appropriate processes. Most river models are time step needs to be selected. For concerned only with downstream ad- example, streams may require short vection and dispersion. Lake and es- time steps (hourly or less) while tuary models may include advection lakes, which typically have residence and dispersion in one or more dimen- times in excessof weeks, can gener- sions, as well as the effects of density ally be modeled with longer time stratification. For toxic modeling, it steps (e.g., daily or more). Similarly, may be important to use models loads from NPS models are often which account for near-field mixing lumped together into event or annual since many of these pollutants may loadings. exert maximum toxicity close to the point of discharge. To incorporate • Spatial characteristics- This includes both point and nonpoint sourcesinto the number of dimensions simulated TMDLs, it will be important to con- and the degree of spatial resolution. sider integrated watershed models: In most stream models, one-dimensional models are used since typically Model selection vertical and horizontal gradients are small. For large lakes and estuaries, A model should be selected based on its two- or three-dimensional models adequacy for the intended use, for the specific waterbody, and for the critical condi- may be more appropriate because tions occurring at that waterbody. While the both vertical and horizontal concen- selection of an appropriate model should be tration gradients commonly occur. made by a water quality analyst, it is useful Segmented or multiple catchment for program managersto be familiar with the models may be more appropriate for decisions which must be made. Four basic heterogeneous watersheds, whereas,

48 steps have been identified that an analyst ditions, stream flow rates, meteoro- would go through to select an appropriate logical conditions, etc. model: . l m - These mod- l Identify models applicable to the sit- els are a compromise between uation. steady-state models and dynamic models. Quasi-dynamic models as- l Define the appropriate level of anal- sume most of the above factors re- ysis. main constant, but allow one or more of them to vary with time, for example 0 Incorporate practical constraints into waste loading rates or stream flow the selection criteria. rates. Some of the models hold the waste loading and flow rates constant, 0 Select a specific model. but predict effects such as the diurnal . . variations in dissolved oxygen due to to the sltuatlon . algal photosynthesis and respiration. An obvious choice for narrowing the selec- . tion of an appropriate model is based on the 0 s - These models pre- waterbody type (river, estuary, or lake) and dict temporal and spatial variations in the type of analysis (BOD/DO, toxics, etc.) water quality due to varied loadings, A preliminary list of models may also be flow conditions, meteorological con- screenedby selecting models which consider ditions, and internal processeswithin the appropriate constituents and processes the watershed or waterbody. Dy- that are important for the pollutant being namicmodels are useful for analyzing studied. transient events(e.g., storms and long . term seasonal cycles) such .as those e of e . important in lake eutrophication Four types of models are: analyses. m - These in- The above model types are listed in order clude dilution and massbalance cal- of increasing complexity, data requirements, culations, Streeter-Phelps equations and cost of application. In addition, lognor- and modifications thereof, analytical mal probabilistic models and Monte Carlo solutions to transport equations, simulation techniques have been used to steady-statenutrient loading models, modify some of the above approaches. regression models, and other simpli- Probabilistic models use lognormal proba- fied modeling procedures that can be bility distributions of model inputs to calcu- performed on desk top calculators. late probability distributions of model output. Since this method does not incorpo- ter & rate fate and transport processes,it can only be used to predict the concentration of a These models compute average spa- substanceafter complete mixing and before tial profiles of constituents along a decay or transformation significantly alters river or estuary assuming everything the concentration Monte Carlo simulations remains constant with time, including combine probabilistic inputs with determin- loadings, upstream water quality con- istic models. A fate and transport model is run a large number of times based on ran-

49 domly selected input values. The output overall removal efficiencies of the sources from these models are then rank ordered to are set so they are all equal. In the latter, the produce a frequency distribution. These fre- incremental removal efficiencies beyond the quency distributions may then be compared current discharge are equal. This method is to instream criteria (e.g., criteria maximum appropriate when the incremental removal concentration (CMC) and criteria continu- efficiencies are relatively smal& so that the ous concentration (CCC)) to determine if necessaryimprovement in water quality can water quality standards are met. be obtained by minor improvement in treatment at each point source, at little cost. . . 1 . In general, the analyst should consider the data The second common allocation method requirements for each level of analysis, the specifies equal effluent concentrations. This availability of historical data, the modeling is similar to equal percent removal if influent effort required for each level of analysis,and concentrations at all sources are approxi- available resources. Availability of histori- mately the same. However, if one source has substantially higher influent levels, then cal data for calibration and verification is one equal effluent concentrations will require of the key cost savingsconsiderations. higher overall treatment levels than the . equal percent removal approach. ctasDeclfic . The analyst should consider model familiarity, technical sup The third commonly used method of al- port and model availability, documentation locating loads can be termed a hybrid quality, application ease, and professional method. With this method, the criteria for recognition and acceptance of a model. waste reduction may not be the same from one source to the next. One source may be PoWantAlLocahn Schemes allowed to operate unchangedwhile another may be required to provide the entire load Individual States use various load alloca- reduction. More generay, a proportional- tion schemesappropriate to their needs and ity rule may be assigned that requires the may specify that a particular method be used. percent removal to be proportional to the Methods of allocating loads have been his- input source loading or flow rate. torically applied to point sources. Applica- tion of these methodologies to nonpoint MultipleDisduuges sources has not been well studied to date. Three common methods for allocating loads TMDLs are particularly critical for (equal percent removal, equal effluent con- waterbodies when the effect from multiple centrations, and a hybrid method) are dis- pollution sources overlap. The key concern cussedbelow. Other methods are detailed associatedwith multiple point or nonpoint in another EPA document3 pollution sources is the potential for combined impacts. To perform this analysis, it The first method is equal percent re- may be necessaryto apply near-field mixing moval and exists in two forms. In one, the models (mixing zone analysis) in addition to

34 USEPA. 1985. Technical Support Document for Water Quality-based Toxics ControL OWlOWEP and OWRS, EPA 440/4-85-032. Washington, D.C. A revised draft (April 23.1990) is available and will replace the 1985Guidance when final&d.

50 a far-field model which considers pollutants larly, tradeoffs between nonpoint sources from numerous point or nonpoint sources are also acceptable. (after the mixing zone). A recommended procedure for evaluating toxicity from mul- The Dillon Reservoir (west of Denver, tiple ’ charges is summarizd in EPA guid- Colorado) is an example of point and non- ance.!P point source phosphorus load tradeoffs. In this example, the cost associatedwith point AkYkatbn Tmzdkofls source reduction was $1.5 million per year, whereas the cost associated with NPS con- Where appropriate and technically feasi- trols was $0.2 to $1.0 million per year. Be- ble, certain cost-effective benefits may be cause of this cost differential, tradeoffs gained by making tradeoffs among allowed publicly-owned treatment works to wasteload allocations. Such a practice is sim- achieve reductions in phosphorus loads to ilar to what would be done during the initial the Dillon Reservoir by controlling NPSs considerations of tradeoffs of loads between rather than expanding the sewagetreatment point and nonpoint sources. In the case of system. watershed or estuary management, this may be particularly useful to achieve pollution Persistent and/or Highly reduction in the most cost-effective manner BioaccumuCative Toxic Polhmts possible. Persistent and/or bioaccumulative toxic The incentive for trading load allocations pollutants require special attention during is to achieve the required level of control by analysisof toxicity and TMDL development. choosing to control one pollutant source The primary concern is that toxic pollutants over another. Technological feasibility, eco- that enter a waterbody at levels that are non- nomic issues,and regulatory authority are all toxic in the water column may accumulate in factors to consider when trading allocations. sediment or aquatic life. These pollutants For example, to reduce nutrient loads to a may then adversely affect aquatic&ildlife or receiving water, nonpoint source controls pose a risk to humans by exposure to hazard- that can be adequately maintained and en- ous chemicals through consumption of con- forced, may be much more cost effective taminated fish or shellfish. Chemicals that than increasing the level of control on a point bioaccumulate at high rates include some source discharger. metals, organic compounds, and or- ganometallic compounds. Current technical Pollutant trades are most likely to occur guidance for wasteload allocation (see Ap- between point and nonpoint sources. How- pendix A) summarize a number of models ever, where effluents from different point which are appropriate for modeling the fate source dischargers are comparable, trades and transport of toxics in streams/rivers, may be acceptable so long as water quality lakes, and estuaries. Additional details for standards(including antidegradation regula- assessingand controlling risk have been ad- tions and policies) and minimum applicable dressedin technical support documentation. technology-based controls are met. Sirni-

35 USEPA. 1985. Tcchical Support Document for Water Quality-based Toxiu Control. OW/OWEP and OWRS, EPA 440/4-85-032.Washington, DC. A revised draft (April 23.1590) is available and will replace the 1985Guidance when final&d.

51 Useof Two-nun&w Crircrio is very important, the frequency should be decreased.) Becauseof inherent variation in effluent and receiving water flows and pollutant con- Although these criteria are mostly used centrations, specifying a concentration that for application to low flow conditions, the must not be exceeded at any time or place toxicological basis for the criteria is equally may not be appropriate for the protection of valid for high flow conditions. It is important aquatic life. The format usually selected for for States to protect designated water uses expressing water quality criteria to protect during all flow conditions; therefore, the aquatic life consists of recommendations two-number criteria should be used for all concerning concentration magnitudes, dura- flow conditions unless separate guidance for tion of averaging periods, and average fre- adopting wet weather criteria is available. quencies of allowed excursions. Use of this However, States should apply duration and magnitudeduration-frequency format al- frequency parameters to account for the high lows water quality criteria for aquatic life to flow, intermittent nature of nonpoint source be adequately protective without being as loadings. overprotective as if criteria were expressed using a simpler format. In many cases,these sediment Issues considerations are evaluated during the standards setting process and TMDLS are The problems associatedwith clean and used to develop controls that result in attain- contaminated sediment are not the same. ment of applicable water quality standards. Clean sediment can impair fish reproduction by silting-up spawning areas, and can in- Duration of exposure considers the creaseturbidity. Draft (clean) sediment cri- amount of time organisms will be exposedto teria have been developed in Idaho that toxicants. It is expressed as that period of include turbidity, inter-gravel dissolved oxy- time over which the instream concentration gen, and cobble embeddedness.The criteria is averagedfor comparison with criteria con- developed may be most appropriate for sal- centrations. Frequency is defined as how monid streams,but the framework may have often exposures that exceed the criteria can wide application. The major concerns re- occur during a given period of time (e.g., garding contaminated sediment are pollu- once every three years) without unaccept- tant releases to the water column, ably affecting the community. To account bioaccumulation, and biomagnification. for acute toxic effects, States may adopt Sediment criteria being developed by EPA acute criteria expressedas the criteria maxi- have centered on evaluating and developing mum concentration (CMC) occurring in a an understanding of the principal factors that one-hour averaging period. Similarly, influence the sediment/contaminant interac- chronic criteria expressedas the criteria con- tions with the water column (Equilibrium tinuous concentration (CCC) should be de- Partitioning Approach). (The ScienceAdvi- veloped as toxicant concentrations which sory Board will be reviewing methods for should not be exceeded over longer periods establishing sediment criteria for metal con- of time. For the purposes of modeling, the taminants and procedures for establishing ambient concentration should not exceed standardized bioassays in 1991.) Through the CMC more than once every three years. such an understanding, exposure estimates (If the biological community is under stress of benthic and other organisms can be made. becauseof spills, multiple dischargers,or has Chronic water quality criteria, or possibly a low recovery potential, or if a local species other toxicological endpoints, can then be used to predict potential biological effects.

52 In some cases, sediment criteria alone sions can be made. Additionally, ground would be sufficient to identify and to estab- water inputs through sediments should be lish clean up levels for contaminated sedi- distinguished from inputs from the sediment merits. In other cases,the sediment criteria alone, so that proper control measures are should be supplemented with biological or implemented. other types of analysis before clean-up deci-

53 APPENDIX E - MATHEMATICAL MODEL SUPPORT

The Center for Exposure Assessment (HSPF9, WASP4, EXAMS2, DYNTOX), Modeling (CEAM) was established in July, toxic pollution of lakes and estuaries 1987to meet the water quality and exposure (WASP4, EXAMS2), conventional pollu- modeling needs of States and EPA program tion of lakes and estuaries (WASP4), near- and Regional offices. CEAM provides ex- field mixing and dilution in rivers, lakes, posure assessmenttechnology, training, and estuaries, and oceans (CORMIX1), cohe- consultation for analysts and decisions-mak- sive sediment transport (SED2D-V), river ers operating under various legislative man- and tidal hydrodynamics (DYNHYD5, dates, including the Clean Water Act. RIVMOD, HYDRO2D-V, HYDRO3D), geochemical equilibrium (MINTEQA3), With support and resources from the and aquatic food chain bioaccumulation Monitoring Branch in the Assessment and (FGETS). Software and databasesdistrib- Watershed Protection Division, Office of uted to aid in data analysisinclude ANNIE- Water Regulations and Standards, CEAM IDE, DBAPE, and the CLC Database. maintains a distribution center for water Currently available models are summarized quality models and databases for the user below. Those with no version number are community. Users are kept up to date available as test code, and will be routinely through user group meetings, a newsletter, distributed when fully tested. and an electronic bulletin board. For the major wasteload allocations models, CEAM Table E-1 CEAM Supported Models offers 2- to 5-day training courses at EPA Headquarters, Regional sites, and the Ath- DYNTOX 1.0 ens Environmental Research Laboratory fa- EXAMSII 2.94 cility. Longer-term “on-the-job” training at HSPF 9.01 CEAM for individuals is also available. MINTEQA3/PRODEFA3 3.00 Technical assistance and review are pro- PRZM 1.00 vided by CEAM scientists and engineers, as QUAL2E-UNCAS 3.11 well as by affiliated academics and consul- SWMM 3.3 tants. Exposure calculations and assess- WASP4/TOXI/EUTRO 4.22 ments for especially difficult or unusual DYNHYD5 5.02 discharge situations can be arranged as re- GCSOLAR 1.10 sources allow. FGETS 1.00 CORMIX1 1.00 The center currently distributes 21 simu- ANNIE-IDE 1.11 DBAPE 1.05 lation models and databases. These can be CLC Database 2.00 applied to urban runoff (SWMM4, HSPF9), RUSTIC - leaching and runoff from soils (PRZM, MULTIMED - HSPF9), transport through soil and ground HYDRO2D-V - water (MULTIMED, RUSTIC), conven- SED2D-V - tional pollution of streams (QUAL2E, HYDRO3D - HSPF9, WASP4), toxic pollution of streams RIVMOD -

54 CEAM operates an Electronic Bulletin model documentation, and 4) a message Board System (BBS) to meet the increasing area for discussion of computer modeling demand for supported exposure assessment problems and enhancements. To accessthe models. It allows efficient communication CEAM BBS, a user must call 404/546-3403 between users with modem-equipped com- or FTS 250-3402 and follow the interactive puters and CEAM support staff as well as prompts. The communications parameters immediate acquisition of models by those are 9600/2400/1200baud, no parity, 8 data under extreme time pressure. The services bits, and 1 stop bit. presently offered are: 1) downloading of CEAM supported models, 2) uploading of Information about obtaining the models user input data setsfor staff review and prob- may be obtained by writing the Center for lem solving, 3) a bulletin area listing current Exposure Assessment Modeling. U.S. EPA, CEAM activities and events,such astraining College Station Road, Athens, GA 30613, or courses,helpful hints about the models, and by calling 404-546-3549.

55 APPENDIX F - GENERAL EPA/STATE AGREEMENT OUTLINE FOR DEVELOPMENT OF TMDLs

Since conditions, procedures, and methodologies may vary between EPA Regions and their States, a general outline of an example agreement is provided. This outline can be used in conjunction with the referenced technical guidance documents to prepare EPA/State Agree- ments. I. General A. Purpose, Scope, and Authority B. Statement of Policy II. Water Quality Standards Considerations A. General B. Type of Stream Classifications III. Allocation Procedures and Policies A. Basic Approach for Establishing Boundaries for TMDL Development B. Determination of TMDL, WLA, and LA Using Water Quality Models C. Determination of TMDL, WLA, and LA Using Other Analytical Tools D. Special Case Policies IV. Public Participation Process V. Approval of TMDL, WLA, and LA VI. Incorporation of Allocations into NPDES Permits A. General B. Priority Considerations Appendix. State Continuing Planning Process(CPP) APPENDIX G - CAUSES ANDSOURCES OF POLLUTION

Causes and Sources: Section 305(b) Waterbody System User’s Guide, Third Edition (Version 2.0), August 1989,USEPA, Office of Water, Assessmentand Watershed Protection Division, pagesA-27 through A-31.

Causes Sources Causes are the pollutants or conditions Sources are the point and nonpoint that are causing or expected to a ex- sources of the pollution categories that are ceedancesof water quality standards. One listed as causes identified above. One or or more of the following categories should more of the following categories should be be used to identify causesof impairment: used to identify sourcesof impairment:

- unknown toxicity - organic enrichment/ DO - source unknown - pesticides - salinity/TDS/chlorides - industrial point - municipal point - priority organics - thermal modifications sources sources - nonpriority organics - flow alterations - combined sewer - agriculture overflow - metals - other habitat alterations - silviculture - construction - ammonia - pathogens - urban runoff/storm - resource extraction sewers - chlorine - radiation - land disposal - hydromodification - other organics - oil and grease - habitat modification - nutrients - taste and odor - suspended solids - pH Other categories: - siltation - noxious aquatic plants - atmospheric deposition - storage tank leaks - filling and draining - cause unknown - highway maintenance/ - spills runoff - in-place contaminants - natural - recreational activities - upstream impoundments - salt storage sites

57 LIST OF ACRONYMS

ARAR Applicable or Relevantand Appropriate Requirements AT AdvancedTreatment BAT Best Available Technology BCT Best ConventionalTechnology BMP Best ManagementPractice BOD5 5-dayBiochemical Oxygen Demand BPJ Best ProfessionalJudgement BPT Best PracticableControl Technology CCC Criteria ContinuousConcentration CEAM/BBS Center for ExposureAssessment Modeling/Electronic Bulletin Board System CERCLA ComprehensiveEnvironmental Response, Compensation, and Liability Act CFR Code of Federal Regulations CLP Clean Lakes Program CMC Criteria MaximumConcentration CPP Continuing PlanningProcess CSO CombinedSewer Overflow CWA Clean Water Act DO DissolvedOxygen EPA EnvironmentalProtection Agency FR Federal Register ICS Individual Control Strategy LA Load Allocation LC Loading Capacity MOS Margin of Safety NCMP National Coastaland Marine Policy NEP National EstuaryProgram NPDES National Pollutant DischargeElimination System NPS Nonpoint Source POTW Publicly OwnedTreatment Works QA/QC Quality Assurance/QualityControl SARA SuperfundAmendments and ReauthorizationAct TMDL Total Maximum Daily Load TRE Toxic Reduction Evaluation TRI Toxic ReleaseInventory TSD TechnicalSupport Document WBS WaterbodySystem WLA WasteloadAllocation WQMP Water Quality ManagementPlan WWTP WastewaterTreatment Plant

58 SELECTED OFFICES, DIVISIONS, BRANCHES, AND SECTIONS WITHIN EPA

General Contact Phone Number GW Office of Water 382-5700 OWRS Office of Water Regulations and Standards 382-5400 AED Analysis and Evaluation Division 382-5389 ITD Industrial Technology Division 382-7120 FE Criteria and Standards Division 382-7301 AWPD Assessmentand Watershed Protection Division 382-7040 Monitoring Branch 382-7056 Monitoring Management Section (TMDLs/WLAs) Monitoring Analysis Section Water Quality Analysis Branch 382-7046 Information ServicesSection Special Studies Section Exposure AssessmentSection Nonpoint Source Control Branch 382-7085 CleanLakes Section Nonpoint Source Control Section (BMPs/LAs) OMEP Office of Marine and Estuarine Protection 382-7166 OWEP Office of Water Enforcement and Permits 475-8488 OMPC Office of Municipal Pollution Control 382-5850 ODW Office of Drinking Water 382-5543 OGWP Office of Ground Water Protection 382-7077 OWP Office of Wetlands Protection 475-7791

All area cods are 202.