r/EPA
            United States
            Environmental Protection
            Agency
                Office of Water
                (4305)
EPA-823-B-93-002
September 1993
Water  Quality Standards
Handbook
            Second Edition
                       "... to restore and maintain the chemical,
                       physical, and biological integrity of the Nation's
                       waters."

                               Section 101 (a) of the Clean Water Act
                                            Recycled/Recyclable
                                            Printed on paper that contains
                                            at least 50% recycled fiber

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WATER QUALITY STANDARDS

            HANDBOOK

        SECOND EDITION
        Water Quality Standards Branch
       Office of Science and Technology
     U.S. Environmental Protection Agency
           Washington, DC 20460
              September 1993
                     U.S. Environmental Protection Agency
                     ffcgton 5, Library (PL- 12J)
                     77 West Jackson Boulevard, 12th Floor
                     Chicago, IL  60604-3590

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                                          FOREWORD
       Dear Colleague:

       The following document entitled Water Quality Standards Handbook - Second Edition provides guidance
issued in support of the Water Quality Standards Regulation (40 CFR 131, as amended). This Handbook includes
the operative provisions of the first volume of the Handbook issued in 1983 and incorporates subsequent guidance
issued since 1983. The 1993 Handbook contains only final guidance previously issued by EPA—it contains no
new guidance.

       Since the 1983 Handbook has not been updated in ten years, we hope that this edition will prove valuable
by pulling together current program guidance and providing a coherent document as a foundation for State and
Tribal water quality standards programs.  The Handbook also presents some  of the evolving program concepts
designed to reduce human and ecological risks, such as endangered species protection; criteria to protect wildlife,
wetlands,  and sediment quality; biological criteria to better define  desired biological communities in aquatic
ecosystems; and nutrient criteria.

       This Handbook is intended to serve as a "living document," subject to future revisions as the water quality
standards program moves forward, and to reflect the needs and experiences of EPA and the States. To this end,
the Handbook is published in a loose leaf format designed to be placed in a three  ring binder.  EPA anticipates
publishing changes to the Handbook periodically and providing them to Handbook recipients. To ensure mat you
will receive these updates, please copy the update request form in Appendix W and mail it to the address below.

       The Handbook also contains a listing, by title and date, of the guidance issued since the Handbook was
first published in  1983 that is incorporated in the Second Edition. Copies of these documents are available upon
request.

       The Water Quality Standards Handbook - Second Edition provides guidance on the national water quality
standards program.  EPA regional offices and States may have additional guidance that provides more detail on
selected topics of regional  interest.   For information on regional or  State guidance, contact the appropriate
regional water quality standards coordinator listed in  Appendix U.

       EPA invites participation from interested parties  in the water quality standards program, and appreciates
questions on this guidance as well as suggestions and  comments for improvement.  Questions or comments may
be directed to the EPA regional water quality standards coordinators or to:

       David Sabock, Chief
       Water Quality Standards Branch
       Mail Code 4305
       U.S. Environmental  Protection Agency
       401  M Street, S.W.
       Washington, D.C. 20460
       Telephone (202)260-1315
                                                  William R. Diamond, Director
                                                  Standards and Applied Science Division
(9/15/93)                                                                                           iii

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Water Quality Standards Handbook - Second Edition
                                   Note to the Reader
       The Water Quality Standards Handbook, first issued in 1983, is a compilation of EPA's
guidance on the water quality standards program and provides direction for States in reviewing,
revising and implementing water quality standards.  The Water Quality Standards Handbook -
Second Edition retains all the guidance in the 1983 Handbook unless such guidance was specifically
revised in subsequent years.  An annotated list of the major guidance and policy documents on the
water quality standards program issued  since 1983 is included in the Introduction section.  Material
in the Handbook contains only guidance previously issued by EPA; it contains no new guidance.

       The guidance contained in each of the documents listed in the Introduction is either:
1) incorporated in its entirety, or summarized, in the text of the appropriate section of this
Handbook, or 2) attached as an appendix (see Table of Contents).  If there is uncertainty or
perceived inconsistency on any of the guidance incorporated into this Handbook, the reader is
directed to review the original guidance documents or call the Water Quality Standards Branch at
(202) 260-1315. Copies of all original  guidance documents not  attached as appendices may be
obtained from the source listed for each document in the Reference section of this Handbook.

       Copies of this Handbook may be obtained from:

       Office of Water Resource Center, RC-4100
       U. S. Environmental Protection  Agency
       401 M Street, S.W.
       Washington, DC 20460
       Telephone: (202) 260-7786 (voice mail publication request line)
                                              Robert S. Shippen
                                              Editor
                                 NEW POLICY SIGNED

         On October 1, 1993, the Acting Assistant Administrator for Water issued the Office of
   Water Policy and Technical Guidance on Interpretation and Implementation of Aquatic Life Metals
   Criteria.

         Since the policy document was signed to late for inclusion in the Handbook, the complete
   policy document is being sent to the recipients of this Handbook under separate cover. Later this
   fiscal year, you will receive an update, for insertion into the Handbook, reflecting this policy
   document and other new policy and guidance that may be produced in the interim.
IV                                                                                    (9/15/93)

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                                                                            Table of Contents
                               TABLE OF COOTEOTS
Foreword      	iii

Note to the Reader  	iv

Table of Contents	v

Glossary       	GLOSS-1

Introduction    	INT-1

       History of the Water Quality Standards Program	INT-1
       Handbook Changes Since 1983  	INT-5
       Overview of the Water Quality Standards Program  	INT-8
       The Role of WQS  in the Water Quality Management Program  	INT-13
       Future Program Directions	INT-14

Chapter 1 - General Provisions (40 CFR 131 - Subpart A)

       1.1    Scope - 40  CFR 131.1  	1-1
       1.2    Purpose - 40 CFR 131.2	1-1
       1.3    Definitions  - 40 CFR 131.3	1-1
       1.4    State Authority - 40 CFR 131.4  	1-2
       1.5    EPA Authority - 40 CFR 131.5	1-3
       1.6    Requirements for Water Quality Standards Submission - 40 CFR 131.6	1-4
       1.7    Dispute Resolution Mechanism - 40 CFR 131.7	1-4
       1.8    Requirements for Indian Tribes To Qualify for the WQS Program - 40 CFR
             131.8	1-9
       1.9    Adoption of Standards for Indian Reservation Waters  	  1-18
       Endnotes	1-21

Chapter 2 - Designation of Uses  (40 CFR  131.10)

       2.1    Use Classification - 40 CFR  131.10(a)   	2-1
       2.2    Consider Downstream Uses - 40 CFR 131.10(b)	2-4
       2.3    Use Subcategories - 40 CFR  131.10(c)	2-5
       2.4    Attainability of Uses  - 40 CFR 131.10(d)	2-5
       2.5    Public Hearing for Changing Uses - 40 CFR 131.10(e)	2-6
       2.6    Seasonal Uses - 40 CFR 131.10(f)	2-6
       2.7    Removal of Designated Uses  -  CFR 40  	2-6
       2.8    Revising Uses to Reflect Actual Attainment - 40 CFR 131.10(i)	2-8
       2.9    Use Attainability Analyses - 40 CFR 131.10Q) and (k)   	2-9
(9/15/93)

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Water Quality Standards Handbook - Second Edition
Chapter 3 - Water Quality Criteria  (40 CFR 131.11)

       3.1    EPA Section 304(a) Guidance	3-1
       3.2    Relationship of Section 304(a) Criteria to State Designated Uses	  3-10
       3.3    State Criteria Requirements	3-12
       3.4    Criteria for Toxicants	3-13
       3.5    Forms of Criteria  	3-24
       Endnotes	3-34

Chapter 4 - Antidegradation  (40 CFR 131.12)

       4.1    History of Antidegradation	4-1
       4.2    Summary of the Antidegradation Policy	4-1
       4.3    State Antidegradation Requirements	4-2
       4.4    Protection of Existing Uses - 40 CFR 131.12(a)(l)	4-3
       4.5    Protection of Water Quality in High-Quality Waters - 40 CFR 131.12(a)(2) .... 4-6
       4.6    Outstanding National Resource Waters (ONRW) - 40 CFR 131.12(a)(3)	4-8
       4.7    Antidegradation Application and Implementation   	4-10

Chapter 5 - General Policies (40 CFR 131.13)

       5.1    Mixing Zones   	5-1
       5.2    Critical Low-Flows	5-9
       5.3    Variances From Water Quality Standards	5-11

Chapter 6 - Procedures for Review and Revision of Water Quality Standards
             (40 CFR 131 -  Subpart C)

       6.1    State Review and Revision	6-1
       6.2    EPA Review and Approval  	6-8
       6.3    EPA Promulgation	6-13

Chapter 7 - The Water Quality-based Approach to Pollution Control

       7.1    Determine Protection Level	7-2
       7.2    Conduct Water Quality Assessment  	7-3
       7.3    Establish Priorities	7-5
       7.4    Evaluate Water Quality Standards for Targeted Waters  	7-6
       7.5    Define and Allocate Control Responsibilities	7-7
       7.6    Establish Source Controls  	7-8
       7.7    Monitor and Enforce Compliance  	7-12
       7.8    Measure Progress	7-13

References      	REF-1

Summary of Updates	SUM-1
vi                                                                                  (9/15/93)

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                                                                               Table of Contents
Appendices:

       A -    Water Quality Standards Regulation - 40 CFR 131.

       B -    Chronological Summary of Federal Water Quality Standards Promulgation Actions.

       C -    Biological Criteria: National Program Guidance for Surface Waters, April 1990.

       D -    National Guidance: Water Quality Standards for Wetlands, July 1990.

       E -    An Approach for Evaluating Numeric Water Quality Criteria for Wetlands Protection,
              July 1991.

       F -    Coordination Between the Environmental Protection Agency, Fish and Wildlife Service
              and National Marine Fisheries Service Regarding Development of Water Quality
              Criteria and Water Quality Standards Under the Clean Water Act, July 1992.

       G -    Questions and Answers on: Antidegradation, August 1985.

       H -    Derivation of the 1985 Aquatic Life Criteria.

       I -     List of EPA Water Quality Criteria Documents.

       J -     Reserved

       K -    Procedures for the Initiation of Narrative Biological Criteria, October 1992.

       L -    Reserved.

       M -    Reserved.

       N -    IRIS [Integrated Risk Information System] Background Paper.

       O-     Reserved.

       P -    List of 126 Section 307(a) Priority Toxic Pollutants.

       Q -    Wetlands and 401  Certification: Opportunities and Guidelines for  States and Eligible
              Indian Tribes - April 1989.

       R -    Policy on the Use of Biological Assessments and Criteria in the Water Quality
              Program, May 1991.

       S -     Reserved.

       T -    Use Attainability Analysis Case Studies.

       U -    List of EPA Regional Water Quality Standards Coordinators.

(9/15/93)                                                                                   Vii

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Water Quality Standards Handbook - Second Edition
       V -   Water Quality Standards Program Document Request Forms.




       W -   Update Request Form for Water Quality Standards Handbook - Second Edition.
viii                                                                                    (9/15/93)

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         GLOSSARY
WATER QUALITY STANDARDS HANDBOOK




        SECOND EDITION
                                I

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                                                                                     Glossary
                                       GLOSSARY
 The "Act" refers to the Clean Water Act (Public Law 92-500, as amended (33 USC 1251, et seq/) (40
       CFR 131.3.)

 "Acute" refers to a stimulus  severe enough to rapidly induce an effect; in aquatic toxicity tests, an
       effect observed in 96- hours or less is typically considered acute.  When referring to aquatic
       toxicology or  human  health, an acute affect is not always measured in  terms of lethality
       (USEPA, 1991a.)

 "Acute-chronic ratio" (ACR) is the ratio of the acute toxicity of an effluent or a toxicant to its chronic
       toxicity.  It is used as a factor for estimating chronic toxicity on the basis of acute toxicity data,
       or for estimating acute toxicity on the basis of chronic toxicity data (USEPA, 1991a.)

 "Acutely toxic conditions" are those acutely toxic to aquatic organisms following their short-term
       exposure within an affected area (USEPA, 1991a.)

 "Additivity" is the characteristic property of a mixture of toxicants that exhibits a total toxic effect
       equal to the arithmetic sum of the effects of the individual toxicants (USEPA, 1991a.)

 "Ambient toxicity" is measured by a toxicity test on a sample collected from a water body (USEPA,
       1991a.)

 "Antagonism" is the characteristic property of a mixture of toxicants that exhibits a less-than-additive
       total toxic effect (USEPA, 199la.)

 "Aquatic community" is an association of interacting populations of aquatic organisms in a given water
       body or habitat (USEPA, 1990; USEPA, 1991a.)

 "Averaging period" is the period of time over which the receiving water concentration is averaged for
       comparison with criteria concentrations. This specification limits the duration of concentrations
       above the criteria (USEPA, 1991a.)

 "Bioaccumulation" is  the process by which a compound is taken up by an aquatic organism, both from
       water and through food (USEPA, 1991a.)

 "Bioaccumulation factor"  (BAF)  is the ratio of a substance's concentration in tissue versus its
       concentration in ambient water, in situations where the organism and the food  chain are exposed
       (USEPA, 1991a.)

 "Bioassay" is a test used to evaluate the relative potency of a chemical or a mixture of chemicals by
       comparing its effect on a living organism with the effect of a standard preparation on the same
       type of organism. Bioassays are  frequently used in the pharmaceutical industry to evaluate the
       potency of vitamins and drugs (USEPA, 1991a.)
(9/15/93)                                                                           GLOSS-1

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Water Quality Standards Handbook - Second Edition
"Bioavailability" is a measure of the physicochemical access that a toxicant has to the biological
       processes of an organism. The less the bioavailability of a toxicant, the less its toxic effect on
       an organism (USEPA, 1991a.)

"Bioconcentration" is  the process by which a compound is absorbed from  water  through gills or
       epithelial tissues and is concentrated in the body (USEPA, 1991a.)

"Bioconcentration factor" (BCF) is the ratio of a substance's  concentration in tissue  versus its
       concentration in water, in situations where the food chain is  not exposed or contaminated. For
       non-metabolized substances, it represents equilibrium partitioning between water and organisms
       (USEPA, 1991a.)

"Biological criteria" are narrative expressions or numeric values of the biological characteristics of
       aquatic communities based on appropriate reference conditions. As such,  biological criteria serve
       as an index of aquatic community health.  It is also known as biocriteria (USEPA,  1991a.)

"Biological integrity" is the condition of the aquatic community inhabiting unimpaired water bodies of
       a specified habitat as  measured by community structure and  function (USEPA, 1991a.)

"Biological monitoring" describes the use of living organisms in water quality surveillance  to indicate
       compliance with water quality standards or effluent limits and to document water quality trends.
       Methods of biological monitoring may include, but are not limited to, toxicity testing (such as
       ambient  toxicity testing or  whole-effluent toxicity testing) and  biological  surveys. It is also
       known as biomonitoring (USEPA, 1991a.)

"Biological survey or biosurvey" is  collecting, processing,  and analyzing a representative portion of
       the resident aquatic community  to determine its  structural and/or  functional characteristics
       (USEPA. 1991a.)

"Biomagnification" is the process by which the concentration of a compound increases  in species
       occupying successive trophic levels (USEPA, 199la.)

"Cancer potency slope factor" (q,*) is  an indication of a chemical's human cancer-causing potential
       derived using animal studies or epidemiological data on human exposure; based on extrapolation
       of high-dose levels over short periods of time to low-dose levels and a lifetime exposure period
       through the use of a linear model (USEPA, 1991a.)

"Chronic" defines a stimulus that lingers or continues for a relatively long period  of time,  often one-
       tenth of the life span  or more. Chronic should be considered a relative term depending on the
       life span of an organism. The measurement of a chronic effect can be reduced growth, reduced
       reproduction, etc., in addition to  lethality (USEPA, 1991a.)

"Community component" is a general term that may pertain to the biotic guild (fish, invertebrates,
       algae), the taxonomic category (order, family, genus,  species), the  feeding strategy (herbivore,
       omnivore, predator),  or the  organizational  level (individual, population, assemblage)  of  a
       biological entity within the aquatic community (USEPA,  1991a.)
GLOSS-2                                                                              (9/15/93)

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                                                                                      Glossary

"Completely mixed condition" is defined as no measurable  difference in the concentration of a
       pollutant exists across a transect of the water body (e.g., does not vary by 5%) (USEPA,
       1991a.)

"Criteria" are elements of State water quality standards, expressed as constituent concentrations, levels,
       or narrative  statements, representing a quality of water that supports a particular use.  When
       criteria are met, water quality will generally protect the designated use (40 CFR 131.3.)

"Criteria continuous concentration" (CCC) is the EPA national water quality criteria recommendation
       for the highest instream concentration of a toxicant or an effluent to which  organisms can be
       exposed indefinitely without causing unacceptable effect (USEPA,  199la.)

"Criteria maximum concentration" (CMC) is the EPA national water quality criteria recommendation
       for the highest instream concentration of a toxicant or an effluent to which  organisms can be
       exposed for a brief period of time without causing an acute effect (USEPA,  1991a.)

"Critical life stage" is the period of time in an organism's lifespan in which it is the most susceptible
       to adverse effects caused by  exposure to toxicants, usually during early development (egg,
       embryo,  larvae). Chronic toxicity tests are often  run on  critical life  stages to replace long
       duration, life cycle tests since the most toxic effect usually occurs  during the critical life stage
       (USEPA,  1991a.)

"Design flow" is the flow used for steady-state waste load allocation modeling (USEPA, 1991a.)

"Designated uses" are those uses specified in water quality standards for each water body or segment
       whether or not they  are being attained (40 CFR 131.3.)

"Discharge length scale" is the square root of the cross-sectional area of any discharge outlet (USEPA,
       1991a.)

"Diversity"  is the number and abundance of biological taxa in a specified location (USEPA, 1991a.)

"Effective concentration" (EC) is a point estimate of the toxicant concentration that would cause an
       observable adverse effect (such as death, immobilization, or serious incapacitation) in a given
       percentage of the test organisms (USEPA, 1991a.)

"Existing uses" are those uses actually attained in the water body on  or after November 28, 1975,
       whether or not they  are included in the water quality standards (40 CFR  131.3.)

"Federal Indian Reservation," "Indian Reservation," or "Reservation"  is defined as all land within
       the limits  of any Indian reservation under the jurisdiction of the  United States Government,
       notwithstanding the  issuance of any patent,  and including rights-of-way running through the
       reservation (40 CFR 131.3.)

"Final acute value" (FAV) is an  estimate of the concentration of the toxicant corresponding to a
       cumulative probability of 0.05 in the acute toxicity values for all genera  for which acceptable
       acute tests have been conducted on the toxicant (USEPA, 1991a.)
(9/15/93)                                                                            GLOSS-3

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Water Quality Standards Handbook - Second Edition
"Frequency" is how often criteria can be exceeded without unacceptably affecting the community
       (USEPA, 1991a.)

"Harmonic  mean flow" is the  number  of daily flow measurements divided by the sum of the
       reciprocals of the flows. That is, it is the reciprocal of the mean of reciprocals (USEPA, 1991a.)

"Indian Tribe" or "Tribe" describes any Indian Tribe, band, group, or community recognized by the
       Secretary of the Interior and exercising governmental authority over a Federal Indian reservation
       (40CFR131.3.)

"Inhibition concentration" (1C)  is a point estimate of the toxicant concentration that would cause a
       given  percent reduction (e.g., IC25) in  a non-lethal biological measurement  of the test
       organisms, such as  reproduction or growth (USEPA, 1991a.)

"Lethal concentration" is the point estimate of the toxicant concentration that would be lethal to a
       given percentage of the test organisms during a specified period (USEPA,  1991a.)

"Lipophilic" is a high affinity for lipids (fats) (USEPA,  1991a.)

"Load allocations" (LA) the portion of a receiving water TMDL that is attributed either to one  of its
       existing or  future nonpoint sources of pollution  or to natural  background sources  (USEPA,
       1991a.)

"Lowest-observed-adverse-effect-level" (LOAEL) is the lowest concentration of an effluent or toxicant
       that results in statistically significant adverse health effects as observed in chronic or subchronic
       human epidemiology studies or animal exposure (USEPA, 199la.)

"Magnitude" is how much of a  pollutant (or pollutant parameter such as toxicity),  expressed as a
       concentration or toxic unit is allowable (USEPA, 1991a.)

"Minimum level" (ML) refers to the level at which the entire analytical system gives recognizable mass
       spectra and acceptable calibration points when analyzing for pollutants of  concern. This level
       corresponds to the lowest point at which the calibration curve is determined (USEPA, 1991a.)

"Mixing zone" is an area where an effluent discharge undergoes initial dilution and  is extended to cover
       the secondary mixing in the ambient water body. A mixing zone is an allocated impact zone
       where water quality criteria can be exceeded as long as acutely toxic conditions are  prevented
       (USEPA, 1991a.)

"Navigable waters" refer  to the  waters of the  United States, including the territorial seas (33  USC
       1362.)

"No-observed-adverse-effect-lever1 (NOAEL) is a tested dose of an effluent or a toxicant below which
       no adverse  biological effects are observed, as identified  from chronic or subchronic human
       epidemiology studies or animal exposure studies (USEPA, 1991a.)
GLOSS-4                                                                            (9/15/93)

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                                                                                      Glossary

"No-observed-effect-concentration" (NOEC) is the highest tested concentration of an effluent or a
       toxicant at which no adverse effects are observed on the aquatic test organisms at a specific time
       of observation. Determined using hypothesis testing (USEPA, 1991a.)

"Nonthreshold effects" are associated with exposure to chemicals that have no safe exposure levels.
       (i.e., cancer) (USEPA, 1991a.)

"Persistent pollutant" is not subject to decay, degradation, transformation, volatilization, hydrolysis,
       or photolysis (USEPA,  1991a.)

"Pollution" is defined as the man-made or man-induced alteration of the chemical, physical, biological
       and radiological integrity of water (33 USC 1362.)

"Priority pollutants"  are those pollutants listed by the Administrator under section 307(a) of the Act
       (USEPA, 1991a.)

"Reference ambient concentration" (RAC) is the concentration of a chemical in water which will not
       cause adverse impacts to human health; RAC is expressed in units of mg/1 (USEPA,  1991a.)

"Reference conditions" describe the characteristics of water body segments least impaired by human
       activities.  As such, reference conditions can be used to describe attainable biological or habitat
       conditions for water body  segments with common watershed/catchment characteristics within
       defined geographical regions.

"Reference tissue concentration" (RTC) is the concentration of a chemical in edible fish or shellfish
       tissue which will not cause adverse impacts to human health when ingested. RTC is expressed
       in units of mg/kg (USEPA, 1991a.)

"Reference dose" (RfD) is an  estimate of the daily exposure to human population that is likely to be
       without appreciable risk of deleterious effect during a lifetime; derived from NOAEL or LOAEL
       (USEPA, 199 la.)

"Section 304(a) criteria" are developed by EPA under authority of section 304(a) of the Act  based on
       the latest scientific information on the relationship that the effect of a constituent concentration
       has on particular aquatic species and/or human health. This information is issued periodically
       to the States as guidance for use in developing criteria (40 CFR 131.3.)

"States" include: the 50 States, the District of Columbia, Guam, the Commonwealth of Puerto Rico,
       Virgin  Islands,  American  Samoa,  the  Trust  Territory  of  the Pacific Islands,   and  the
       Commonwealth of the Northern Mariana Islands, and Indian Tribes that EPA determines qualify
       for treatment as States for the purposes of water quality standards (40 CFR 131.3.)

"Steady-state model"  is a fate and transport model that uses constant values of input variables to
       predict constant values of receiving water quality concentrations (USEPA,  1991a.)

"STORET"  is EPA's computerized water quality database that includes physical,  chemical, and
       biological data  measured in water bodies throughout the United States (USEPA, 1991a.)
(9/15/93)                                                                            GLOSS-5

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Water Quality Standards Handbook - Second Edition
"Sublethal" refers to a stimulus below the level that causes death (USEPA, 1991a.)

"Synergism" is the characteristic property of a mixture of toxicants that exhibits a greater-than-additive
       total toxic effect (USEPA,  1991a.)

"Threshold effects" result from chemicals that have a safe level (i.e., acute, subacute, or chronic
       human health effects) (USEPA, 1991a.)

"Total maximum daily load" (TMDL) is the sum of the individual waste load allocations (WLAs) and
       load allocations (LAs); a margin of safety is included with the two types of allocations so that
       any additional loading, regardless of source, would  not produce a violation of water quality
       standards (USEPA, 1991a.)

"Toxicity test" is a procedure to determine  the toxicity of a chemical or an effluent using living
       organisms. A toxicity test measures the degree of effect on exposed test organisms of a specific
       chemical or effluent (USEPA, 1991a.)

"Toxic pollutant" refers  to those pollutants, or combination of pollutants,  including disease-causing
       agents, which after discharge and upon exposure, ingestion, inhalation, or assimilation into any
       organism, either directly from the environment or indirectly by ingestion through food chains,
       will, or on  the basis of information available to the administrator,  cause death,  disease,
       behavioral abnormalities,  cancer,  genetic mutations,  physiological malfunctions  (including
       malfunctions in reproduction) or physical deformations, in such organisms or their offspring (33
       USC section 1362.)

"Toxic units" (TUs) are a measure of toxicity in an effluent as determined by the acute toxicity units
       (TUa) or chronic toxicity units (TUc) measured (USEPA,  1991a.)

"Toxic unit acute" (TUa) is the reciprocal of the effluent concentration that causes 50 percent of the
       organisms to die by the end of the acute exposure period (i.e., 100/LC50) (USEPA, 1991a.)

"Toxic unit chronic" (TUc) is the reciprocal of the effluent concentration that causes no observable
       effect on the test organisms  by  the end of the chronic  exposure period  (i.e., 100/NOEC)
       (USEPA, 1991a.)

"Use attainability analysis" (UAA)  is a structured scientific assessment of the factors affecting the
       attainment of the use which may  include physical,  chemical, biological, and economic factors
       as described in section 131.10(g) (40 CFR 131.3.)

"Waste load allocation"  (WLA) is the portion of a receiving water's TMDL that  is allocated to one
       of its existing or future point sources of pollution (USEPA, 1991a.)

"Water quality assessment" is an evaluation of the condition of a water body using biological surveys,
       chemical-specific analyses of pollutants in water bodies, and toxicity tests (USEPA, 1991a.)

"Water quality limited segment" refers to any segment where it is known that water quality does not
       meet applicable water quality standards and/or is not  expected to meet applicable water quality
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                                                                                        Glossary

       standards even after application of technology-based effluent limitations required by sections
       301(b)(l)(A) and (B) and 306 of the Act (40 CFR 131.3.)

11 Water quality standards" (WQS) are provisions of State or Federal law which consist of a designated
       use or uses for the waters of the United States, water quality criteria for such waters based upon
       such uses.  Water quality standards are to protect public health or welfare, enhance the quality
       of the water and serve the purposes of the Act (40 CFR 131.3.)

"Waters of the United States" refer to:

       (1)    all waters which are currently used,  were used in the past, or may be susceptible to use
              in interstate or foreign commerce, including all waters which are subject to the ebb and
              flow of the tide;

       (2)    all interstate waters,  including interstate wetlands;

       (3)    all other waters such as intrastate lakes, rivers, streams (including intermittent streams),
              mudflats, sandflats, wetlands,  sloughs,  prairie potholes, wet meadows, playa lakes, or
              natural ponds the use or degradation of which would affect or could affect interstate or
              foreign commerce, including any such waters:

              (i)    which are or could be used by interstate or foreign travelers for recreational or
                    other purposes;

              (ii)    from  which fish or shellfish are or could be taken and sold in interstate or foreign
                    commerce; or

              (iii)   which are  or could be used for industrial purposes  by industries in  interstate
                    commerce.

       (4)    all impoundments of waters otherwise defined as waters of the United States under this
              definition;

       (5)    tributaries of waters in paragraphs (1) through (4) of this definition;

       (6)    the territorial sea; and

       (7)    wetlands  adjacent to  waters (other than waters that are themselves wetlands) identified
              in paragraphs (1) through (6) of this definition. "Wetlands"  are defined as those areas
              that are inundated or saturated by surface or groundwater at a frequency and duration
              sufficient to  support, and that under normal circumstances do support, a prevalence of
              vegetation typically adapted for life in saturated soil  conditions.   Wetlands generally
              include swamps, marshes, bogs, and similar areas.

       Waste  treatment systems,  including treatment ponds  or lagoons  designed  to  meet  the
       requirements of the  Act (other than cooling ponds as defined in 40 CFR 423.11(m) which also
       meet the criteria for this definition) are not  waters of the United States. (40 CFR 232.2.)
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"Whole-effluent toxicity" is the total toxic effect of an effluent measured directly with a toxicity test
       (USEPA, 1991a.)
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      INTRODUCTION
WATER QUALITY STANDARDS HANDBOOK




        SECOND EDITION

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                                                                                  Introduction
                                    IOTRODUCTION
       HISTORY OF THE WATER QUALITY STANDARDS PROGRAM
Statutory History

The first comprehensive  legislation for water
pollution control was the Water Pollution Control
Act of 1948  (Public Law 845, 80th Congress).
This law, passed after a half century of debate on
the responsibility of the Federal Government for
resolving water  pollution  problems,   adopted
principles of State-Federal cooperative program
development,   limited   Federal   enforcement
authority,  and  provided   limited   financial
assistance.  These concepts were continued in the
Federal Water Pollution Control Act (FWPCA) of
1956 (Public Law 660, 84th Congress) and in the
Water Quality Act of 1965. Under the 1965 Act,
States  were directed to  develop  water quality
standards for interstate waters.  As  a  result of
enforcement complexities and other problems,
however, this  approach  was  not  sufficiently
effective. In the FWPCA Amendments of 1972
(Public Law 92-500),  Congress  established  a
discharge permit system and provided a broader
Federal  role through more  extensive  Federal
grants to finance local sewage treatment systems
and  through   Federal   (EPA)   setting   of
technology-based  effluent limitations.  The 1972
Amendments extended the water quality standards
program  to intrastate waters and  provided for
implementation of water quality standards through
discharge permits.

Section 303(c) of the 1972 FWPCA Amendments
(33 USC 1313(c)) established the statutory basis
for the current water quality standards program.
It  completed  the  transition from the previously
established program of water quality standards for
interstate waters to one requiring standards for all
surface waters of the United States.
Although  the  major  innovation  of the  1972
FWPCA was technology-based controls, Congress
maintained the concept of water quality standards
both as a mechanism  to establish goals for the
Nation's waters and as a regulatory  requirement
when standardized  technology controls for point
source discharges and/or nonpoint source controls
were inadequate.  In recent years, Congress and
EPA have given these water quality-based controls
new emphasis in the continuing quest to enhance
and maintain water quality to protect the public
health and welfare.

Briefly stated, the key  elements of section 303(c)
are as follows:

 (1)  A water quality standard is defined as the
     designated beneficial  uses  of  a  water
     segment  and  the  water  quality  criteria
     necessary to support those uses;

 (2)  The  minimum  beneficial  uses   to  be
     considered by States  in  establishing water
     quality  standards  are  specified as  public
     water supplies,  propagation of  fish  and
     wildlife,  recreation,   agricultural   uses,
     industrial  uses, and navigation;

 (3)  A requirement specifies that State standards
     must protect  public  health  or  welfare,
     enhance the quality of water, and serve the
     purposes of the Clean Water Act;

 (4)  A  requirement specifies that States must
     review their standards at least once each 3-
     year  period using a process that  includes
    public participation;
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 (5)  The process is described for EPA review of
     State standards that might ultimately result in
     the promulgation of a superseding Federal
     rule in cases where a State's standards are
     not   consistent   with   the   applicable
     requirements of the CWA,  or in situations
     where the Agency determines that Federal
     standards   are   necessary  to  meet   the
     requirements of the Act.

The   Federal  Water  Pollution  Control   Act,
including  the  major  1977,  1981,  and  1987
Amendments are  commonly referred  to as the
"Clean Water Act" (the Act or  CWA).

On February 4,1987, Congress enacted the Water
Quality Act of 1987  (Public Law  100-4), making
substantial additions  to the Clean Water Act and
directly   affecting  the   standards   program.
Congress concluded that toxic pollutants in water
constitute one of the most pressing water pollution
problems. The Water Quality Act provided a new
approach  to  controlling  toxic  pollutants  by
requiring  "...  States to identify waters that do
not  meet  water quality  standards  due to  the
discharge  of toxic substances, to adopt numerical
criteria  for the pollutants in such waters, and to
establish  effluent  limitations   for   individual
discharges to such water bodies" (from Senator
Mitchell,  133  Congressional Record S733).  As
now amended, the Clean Water Act requires that
States adopt numeric criteria for toxic pollutants
listed under section 307(a) of the Clean Water Act
for  which section  304(a)  criteria have  been
published, if the presence of these pollutants is
likely to adversely affect the water body's use.
Guidance on these changes is discussed in detail
in section 3.4 of this Handbook.   Additionally,
for the  first time, the Act explicitly recognizes
antidegradation (see section 303(d)(4) of the Act).
Regulatory History

EPA  first  published  a water quality standards
regulation in 1975 (40 CFR 130.17, promulgated
in 40 F.R. 55334, November 28, 1975) as part of
EPA's water  quality  management  regulations,
mandated under section 303(e) of the Act.  The
first Water Quality  Standards Regulation did not
specifically address  toxic pollutants or any other
criteria.  It simply  required "appropriate"  water
quality criteria necessary to  support designated
uses.

In the late 1970s and early 1980s, the public and
Congress raised concerns about  toxic pollutant
control.  EPA realized that promulgating effluent
guidelines or effluent standards under section 307
of the Act would not comprehensively  address
toxic  pollutants.  So, EPA decided to  use the
statutory  connection  between   water  quality
standards and NPDES permits provided by section
301(b)(l)(C) to effectively control  a range of toxic
pollutants from point sources.  To best accomplish
this process,  the Agency decided to amend the
Water Quality Standards Regulation  to explicitly
address   toxic  criteria  requirements  in  State

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                                                                                   Introduction
standards.  Other legal and programmatic issues
also necessitated a revision  of the Standards
Regulation.   The culmination  of this effort was
the promulgation of the present Water Quality
Standards Regulation on  November 8, 1983 (54
F.R. 51400).

The present Water  Quality Standards Regulation
(40 CFR Part 131) is a much more comprehensive
regulation than its predecessor.  In subpart B, the
Regulation addresses both  the designated  use
component and the  criteria component of a water
quality   standard.     Section   131.11  of  the
Regulation requires States to  review available
information and ".  . .to identify specific water
bodies where  toxic pollutants  may be adversely
affecting water  quality  .  . .  and  must adopt
criteria for such toxic pollutants applicable to the
water body sufficient to  protect the designated
use."  The Regulation provides that either or both
numeric   and  narrative  criteria   may   be
appropriately used in water quality standards.

Since the middle of the  1980's, EPA's annual
program guidance  to  the States  reflected  the
increasing emphasis on controlling toxics.  States
were strongly encouraged to adopt criteria in their
standards for the  pollutants  listed pursuant to
section 307(a) of the Act, especially  where EPA
has published  criteria guidance under  section
304(a) of the Act.

State  reaction to EPA's  initiative  was  mixed.
Several  States proceeded  to adopt large numbers
of  numeric  toxic  pollutant  criteria, although
primarily for the protection of aquatic life.  Other
States relied on  a narrative "free from" toxicity
criterion, using so-called "action levels" for toxic
pollutants or for calculating site-specific criteria.
Few States specifically addressed human  health
protection outside the National Primary Drinking
Water  Standards promulgated under the Safe
Drinking Water Act.

In  support  of  its   1983   regulation,  EPA
simultaneously issued program  guidance entitled
Water Quality Standards  Handbook (December
1983).  The foreword to the guidance noted that
EPA's approach to  controlling  toxics included
both  chemical-specific  numeric  criteria  and
biological testing in  whole-effluents or ambient
waters.  More detailed programmatic guidance on
the application of biological testing was provided
in the Technical Support Document for Water
Quality-based Toxics Control (EPA 44/4-85-032,
September 1985).  This  document  provides the
information needed to  convert chemical-specific
and biologically based  criteria into permit limits
for point source dischargers.

State  water quality standards reviews submitted
began to show the effects of EPA's efforts.  More
and more numeric criteria for toxics were being
included in  State standards as well  as  more
aggressive use of the "free from toxics" narratives
in  setting protective  NPDES  permit  limits.
However,  because of perceived  problems  in
adopting numeric toxic pollutant criteria in State
rulemaking  proceedings,  many  States  were
reluctant to adopt numeric toxics criteria.  Thus,
in 1987,  Congress  responded  to  the lack  of
numeric criteria for toxic pollutants within State
standards  by  mandating State adoption of such
criteria.

In response to  this new congressional  mandate,
EPA redoubled its efforts to promote and assist
State  adoption  of water  quality standards  for
priority toxic pollutants.  EPA's efforts included
the development and  issuance of guidance to the
States on  December  12,  1988, which contained
acceptable implementation procedures for several
new   sections  of  the  Act,  including sections
303(c)(2)(B).
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EPA,   in  devising   guidance  for   section
303(c)(2)(B), attempted to provide States with the
maximum  flexibility that complied with  the
express statutory  language but  also with  the
overriding  congressional   objective:  prompt
adoption and implementation of numeric  toxics
criteria.    EPA  believed  that  flexibility was
important so that each State could comply with
section  303(c)(2)(B) and to the  extent possible,
accommodate its existing water quality standards
regulatory approach. The options EPA identified
are described in section 3.4.1 of this Handbook.

EPA's December 1988  guidance also addressed
the timing issue for State compliance with section
303(c)(2)(B).  The statutory directive was clear:
all State standards triennial reviews initiated after
passage of the Act must include a consideration of
numeric toxic criteria.

States   significantly  responded   to   the  1987
requirement  for   numeric  criteria   for  toxic
pollutants.  For example, in 1986 on average,
each State had 10 numeric criteria for freshwater
aquatic  life.   By  February 1990,  the  average
number of freshwater  aquatic life  criteria was
increased  to 30.    Also,  States  averaged  36
numeric criteria for human health  in February
1990. However, by September 1990, many States
had  failed to  fully satisfy the requirements  of
section 303(c)(2)(B).

The addition of section 303(c)(2)(B) to the Clean
Water Act was an unequivocal signal to the States
that Congress wanted toxics criteria in the State's
water quality standards.   EPA,  consistent with
this mandate,  initiated Federal promulgation  of
toxic  criteria  for  those  States  that  had not
complied with the Act.   EPA proposed Federal
criteria  for  toxic pollutants for 22  States and
Territories, based on a preliminary assessment of
compliance, on November 19,  1991 (56 F.R.
58420), and promulgated toxic criteria for 14  of
those States on December 22,  1992 (57 F.R.
60848).
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                                                                                   Introduction
                        HANDBOOK CHANGES SINCE 1983
 In December, 1983, EPA published its first Water
 Quality  Standards   Handbook.     The  1983
 Handbook was designed to help States implement
 the Water Quality Standards Regulation as revised
 in November 1983 (48 F.R.  51400).  Since then,
 Congress enacted the Water  Quality Act of 1987
 (Public Law  100-4), making substantial additions
 to the Clean  Water Act (CWA) directly affecting
 the standards program. In response to the Water
 Quality Act  of 1987, and as a result of Federal
 promulgation actions,  EPA  amended the Water
 Quality Standards Regulation  several times (see
 Appendices A  and B).   Since 1983 EPA  also
 issued  additional  guidance  to  assist  in   the
 implementation of the WQS Regulation.  Water
 Quality Standards Handbook - Second Edition
 incorporates  all the WQS guidance issued since
 the 1983 Handbook was published.  A summary
 of these guidance documents are as follows.

 EPA Guidance on the Water Quality Act  of
 1987

 On February  4, 1987, Congress enacted the Water
 Quality Act of 1987 (Public Law 100-4), making
 substantial  additions  to  the Clean  Water  Act
 directly affecting the standards program.  Section
 303(c)(2)(B)  of the Clean Water Act requires
 States  to  adopt  numeric  criteria  for  toxic
 pollutants listed under section 307(a) of the Clean
 Water Act for which section 304(a) criteria have
 been published, if the presence of these pollutants
 is likely to  affect  a  water  body's use.   EPA
 published Guidance for State Implementation  of
 WQS for CWA section 303(c)(2)(B) on December
 12, 1988 (USEPA,  1988b).   This  guidance  is
 incorporated into this Handbook at section 3.4.1.

 The  1987 Act  also added a new section 518,
 which requires  EPA to promulgate a regulation
 specifying  how  the  Agency will  authorize
 qualified Indian  Tribes   to  administer  CWA
programs  including section  303 (water quality
 standards)  and   section  401  (certification)
programs.  Section 518  also requires EPA, in
promulgating  this  regulation,  to  establish  a
mechanism to resolve unreasonable consequences
that may result from an Indian Tribe and a State
adopting differing  water  quality standards  on
common bodies of  water.  EPA promulgated a
final regulation on December 12, 1991  (56 F.R.
64875).  Guidance on water quality standards for
Indian Tribes is contained in chapter 1.

Other EPA Guidance

Since  1983,  EPA  also  developed additional
policies and guidance on virtually all areas of the
WQS Regulation.  Following is a complete list of
these guidance documents.

State  Water Quality Standards Approvals:  Use
    Attainability  Analysis Submittals  (USEPA,
     1984d), clarifies  EPA policy on several
    issues regarding approval of water  body use
    designations   less   than   the
    fishable/swimmable goal of the CWA.  See
    section 6.2 for  a discussion of this  topic.

Interpretation   of the   Term   "Existing   Use"
    (USEPA,  1985e),  expands   on  EPA's
    interpretation of when  a use becomes  an
    "existing   use"  as  defined by the  WQS
    Regulation. Discussion of "existing uses" is
    contained in  section 4.4.

Selection of Water Quality Criteria in State Water
    Quality  Standards     (USEPA,  1985f),
    established   EPA   policy  regarding  the
    selection of appropriate water quality criteria
    for  toxic pollutants in State  water quality
    standards.  This guidance preceded both the
    Guidelines for Deriving Numerical  National
    Water  Quality  Criteria for the  for  the
    Protection  of Aquatic Organisms and Their
    Uses  (USEPA,  1985b),   and  the  1988
    guidance  on section  303(c)(2)(B) of  the
    CWA, discussed above. Both of these later
    documents expand  upon the February 1985
    guidance, but the policy established therein
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Water Quality Standards Handbook - Second Edition
     has  not   been   substantively   changed.
     Adoption of criteria for toxic  pollutants is
     discussed in section 3.4.

Variances in Water Quality Standards  (USEPA,
     1985g), reinterprets the factors that could be
     considered  when  granting  water  quality
     standards variances. Variances are discussed
     in section 5.3.

Antidegradation,   Waste  loads,  and  Permits
     (USEPA,   1985h),   clarifies   that   the
     antidegradation   policy   is  an   integral
     component  of water quality standards  and
     must be considered when developing waste
     load  allocations   and  NPDES  permits.
     Antidegradation is discussed in chapter 4.

Questions  and  Answers  on  Antidegradation
     (Appendix G), provides guidance on various
     aspects of the antidegradation policy where
     questions   had   arisen   since  the  1983
     Regulation and Handbook were published.

Antidegradation    Policy   (USEPA,   1985i),
     reiterates the need for  all States to have: (1)
     an antidegradation policy that fully complies
     with the Federal requirements, and (2) a
     procedure for consistently implementing that
     policy.

Answers  to Questions on Nonpoint  Sources  and
     WQS (USEPA,  1986e), responded  to  two
     questions on nonpoint source pollution  and
     water quality standards.  The relationship
     between nonpoint source pollution and water
     quality standards is discussed in section 7.

Determination of "Existing Uses" for Purposes of
     Water  Quality  Standards  Implementation
     (USEPA,   1986f),  responds  to  concerns
     expressed to  EPA on the interpretation of
     when   a  recreational use  becomes  an
     "existing use" as defined by the Regulation.
     Discussion of "existing uses" is contained in
     section 4.4.
Nonpoint  Source Controls and Water Quality
     Standards (USEPA, 1987d), provides further
     guidance on nonpoint sources pollution and
     water  quality  standards  reflecting  the
     requirements of section 319 of the CWA as
     added by the 1987 CWA amendments.

EPA  Designation   of   Outstanding  National
     Resource Waters (USEPA,  1989f), restates
     the   basis   for EPA's   practice  of  not
     designating State  waters as  Outstanding
     National Resource Waters (ONRW) where a
     State does not do so.  ONRWs are discussed
     in section 4.6.

Guidance for the Use of Conditional Approvals
    for State WQS  (USEPA, 1989g), provides
     guidelines  for regional  offices  to use  in
     granting  State  water  quality  standards
     approvals conditioned on the performance of
     specified actions by the State.  Conditional
     approvals are  discussed in section 6.2.3.

Application  of Antidegradation Policy to the
     Niagara River (USEPA, 1989c), provides
     guidance on acceptable interpretations of the
     antidegradation  policy  to help  attain the
     CWA objective to "restore and maintain" the
     integrity of the Nation's waters.

Designation of Recreation Uses (USEPA, 1989h),
     summarizes previously issued guidance, and
     outlines a number of acceptable State options
     for designating  recreational uses. The use
     designation process is discussed in chapter 2.
Biological Criteria: National Program Guidance
    for Surface Waters (Appendix C), provides
     guidance on the effective development and
     application of biological criteria in the water
     quality  standards  program.     Biological
     criteria are discussed in section 3.5.3.

National Guidance: Water Quality Standards for
     Wetlands (Appendix D), provides guidance
     for  meeting the EPA priority  to  develop
     water quality standards for wetlands.
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                                                                                    Introduction
Section 401  certification  and FERC licenses
     (USEPA, 1991h),  clarifies  the  range of
     water quality standards elements that States
     need to apply when making CWA section
     401 certification decisions.  Section 401 of
     the CWA is discussed in  section 7.6.3.

Technical Support Document for Water Quality-
     hosed  Toxics Control,   (USEPA,  1991a),
     provides technical guidance for assessing and
     regulating the discharge of toxic substances
     to the waters of the United States.

Policy on the Use of Biological Assessments and
     Criteria  in   the  Water  Quality  Program
     (USEPA, 1991i), provides  the  basis for
     EPA's policy that biological surveys shall be
     fully integrated with toxicity and  chemical-
     specific assessment methods in State water
     quality programs. Further discussion of this
     policy is contained in section 3.3.

Numeric  Water  Quality Criteria for  Wetlands
     (Appendix  E),  evaluates  EPA's  numeric
     aquatic life  criteria to determine  how  they
     can be applied to wetlands.  Wetland aquatic
     life criteria are discussed in section 3.5.6.

Endangered   Species  Act   Joint   Guidance
     (Appendix F), establishes  a procedure by
     which  EPA,  the U.S.  Fish and Wildlife
     Service,  and the National Marine Fisheries
     Service will consult on the development of
     water quality criteria and standards.

The guidance contained in each of the above
documents is either incorporated  into the text of
the  appropriate  section of  this  Handbook or
attached as  appendices (see Table of Contents).
The reader  is directed to the original guidance
documents for the explicit guidance on  the topics
discussed.    Copies  of all   original  guidance
documents not attached  as  appendices may be
obtained from the source listed for each  document
in the Reference section of this Handbook.
The Water Quality Standards Handbook - Second
Edition is reorganized from  the 1983 Handbook.
An overview  to  Water  Quality  Standards and
Water Quality Management programs has been
added, and chapters 1 through 6 are organized to
parallel the provisions  of  the Water  Quality
Standards  Regulation.     Chapter   7  briefly
introduces the role of water quality standards in
the water  quality-based  approach  to pollution
control.

The Water Quality Standards Handbook - Second
Edition retains all the  guidance in  the  1983
Handbook unless  such guidance was specifically
revised in subsequent years.
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      OVERVIEW OF THE WATER QUALITY STANDARDS PROGRAM
A water quality standard defines the water quality
goals of a water body,  or portion thereof,  by
designating the use or uses to be made of the
water, by setting criteria necessary to protect the
uses, and by preventing  degradation  of water
quality through antidegradation provisions.  States
adopt water quality standards to protect public
health or welfare, enhance the quality  of water,
and serve the purposes of the Clean Water Act.

"Serve the purposes of the Act" (as defined in
sections 101(a), 101(a)(2), and 303(c) of the Act)
means that water quality standards:

•    include   provisions   for  restoring  and
     maintaining   chemical,    physical,   and
     biological integrity of State waters;

•    wherever attainable, achieve a level of water
     quality that provides for the protection and
     propagation of fish, shellfish, and wildlife,
     and  recreation  in   and  on  the  water
     ("fishable/swimmable"); and

•    consider  the use and value of State waters
     for public water supplies, propagation offish
     and  wildlife,  recreation,  agriculture and
     industrial purposes, and navigation.

Section 303(c) of the  Clean Water Act provides
the statutory basis for  the water quality  standards
program.  The regulatory requirements governing
the  program,  the   Water Quality  Standards
Regulation, are published at 40  CFR 131.  The
Regulation is  divided  into  four subparts   (A
through  D), which are summarized below.

General Provisions (40 CFR 131 - Subpart A)

Subpart A includes the scope (section 131.1) and
purpose  (section  131.2)  of  the  Regulation,
definitions of  terms   used in  the  Regulation
(section  131.3), State (section  131.4)  and EPA
(section   131.5)  authority  for  water  quality
standards, and the minimum requirements for a
State water quality standards submission (section
131.6).

On December 12, 1991, the EPA  promulgated
amendments to Subpart A of the Water Quality
Standards Regulation  in response to the  CWA
section 518 requirements (see 56 F.R. 64875).
The Amendments:

•    establish   a   mechanism    to   resolve
     unreasonable consequences  that may result
     from an Indian Tribe and a State adopting
     differing water quality standards on common
     bodies of water (section 131.7); and

•    add procedures by which an Indian Tribe can
     qualify for the  section  303 water  quality
     standards  and  section   401  certification
     programs of the Clean Water  Act (section
     131.8).

The sections of Subpart A are discussed in chapter
1.

Establishment of Water Quality  Standards -
(Subpart B)

Subpart B contains regulatory requirements that
must be included in State water quality standards:
designated  uses (section 131.10),  criteria  that
protect the  designated uses (section  131.11), and
an  antidegradation policy that protects existing
uses and high water  quality  (section 131.12).
Subpart B  also provides for  State  discretionary
policies, such as mixing zones and water quality
standards variances (section 131.13).

Each of these sections  is summarized below and
discussed  in  detail  in chapters 2 through  5
respectively.

     Designation of Uses

The Water  Quality Standards Regulation requires
that States  specify appropriate water uses to be
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                                                                                       Introduction
achieved   and   protected   by   taking   into
consideration the use and value of the water body
for public water supply,  for propagation of fish,
shellfish,   and  wildlife,  and for  recreational,
agricultural, industrial, and navigational purposes.
In  designating  uses  for a  water  body, States
examine the suitability of a  water  body for the
uses  based   on  the physical,  chemical,  and
biological characteristics  of the  water body, its
geographical setting and scenic qualities, and the
social-economic and cultural characteristics of the
surrounding  area.   Each water body does not
necessarily require a unique  set of uses. Instead,
the characteristics necessary  to support a use can
be  identified  so that  water  bodies  having  those
characteristics  might be grouped   together as
supporting particular uses.

Any water body with standards not consistent with
the section 101(a)(2) goals  of the  Act must be
reexamined every  3 years  to determine if new
information  has become available that  would
warrant a revision of the standard.   In addition,
the Regulation requires that where existing water
quality standards specify designated  uses less than
those which are presently  being attained, the State
shall  revise   its standards   to reflect the  uses
actually being attained.

When reviewing uses, States must  perform and
submit to EPA a use attainability analysis if:

•    either the State designates or has designated
     uses that do not include the uses specified in
     section 101(a)(2) of  the Act;

•    the State wishes to remove a designated use
     that is specified in section 101 (a) (2); or

•    the State wishes to  adopt subcategories of
     uses   specified  in  section   101(a)(2)  that
     require   less  stringent  criteria  than  are
     currently adopted.

States may adopt seasonal uses as an  alternative to
reclassifying a water body or segment thereof to
uses requiring less  stringent  criteria. In no  case
may a State remove  an  existing use.   No use
attainability analysis is required when designating
uses  that  include  those  specified  in  section
101(a)(2) of the Act.

     Criteria Development and Review

States adopt water quality criteria with sufficient
coverage of parameters and of adequate stringency
to protect designated uses. In adopting criteria to
protect the designated uses, States may:

•    adopt the criteria that EPA publishes under
     section 304(a) of the Act;

•    modify the section 304(a) guidance to reflect
     site-specific conditions; or

•    use other scientifically defensible methods.

Section  131.11 encourages States to adopt both
numeric  and narrative criteria.  Numeric criteria
are  important where the  cause of  toxicity  is
known or for protection against pollutants with
potential human health impacts or  potential for
bioaccumulation.  Narrative toxic criteria, based
on whole-effluent toxicity (WET) testing, can be
the basis for limiting toxicity in waste discharges
where  a specific pollutant can be  identified as
causing or contributing to the toxicity but  there
are no numeric criteria in the  State standards or
where  toxicity cannot be traced to a particular
pollutant. Whole-effluent toxicity testing is also
appropriate  for  discharges containing  multiple
pollutants because WET testing provides a method
for evaluating synergistic and antagonistic effects
on aquatic life.

Section   303(c)(2)(B) requires  States  to adopt
criteria for all section 307(a) toxic pollutants for
which the Agency  has published criteria under
section 304(a) of the Act, if  the discharge or
presence of  the pollutant  could  reasonably  be
expected to interfere with the designated uses of
the water body.  The section 307(a) list contains
65 compounds and families of compounds, which
the  Agency   has interpreted   to  include  126
"priority" toxic pollutants for regulatory purposes.
If data indicate that it is reasonable to expect that
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one or more of the section 307(a) toxic pollutants
will interfere with the attainment of the designated
use, or is actually interfering with the designated
use, then the State must adopt a numeric limit for
the specific pollutant.  Section 303(c)(2)(B) also
provides that where EPA-recommended numeric
criteria are  not available,  States  shall  adopt
criteria  based  on  biological  monitoring  or
assessment methods.
     Antidegradation   Policy
     mentation Methods
and   Imple-
Water quality standards include an antidegradation
policy and  methods through  which  the State
implements  the antidegradation policy.  Section
131.12 sets out a three-tiered  approach for the
protection of water quality.

"Tier 1" (40CFR 131.12(a)(l)) of antidegradation
maintains   and protects  existing uses and the
water quality necessary to protect these uses.  An
existing use can be established by  demonstrating
that  fishing,  swimming,  or other  uses have
actually  occurred since November 28, 1975, or
that the water quality is  suitable to allow  such
uses to occur,  whether  or  not  such  uses  are
designated uses for the water body in question.

"Tier 2"  (section 131.12(a)(2)) protects the water
quality in waters whose quality is better than that
necessary to protect  "fishable/ swimmable"  uses
of the water body. 40 CFR 131.12(a)(2) requires
that certain  procedures be followed and  certain
showings  be made (an "antidegradation review")
before lowering  water  quality in  high-quality
waters.  In no case may water quality on a Tier II
water body be  lowered  to  the  level at which
existing uses are impaired.

"Tier  3"   (section   131.12  (a)(3))  protects
outstanding  national resource waters (ONRWs),
which are provided the highest level of protection
under  the  antidegradation  policy.    ONRWs
generally include the highest quality waters of the
United   States.      However,   the   ONRW
antidegradation classification also offers  special
protection for waters of  "exceptional  ecological
significance," i.e., those water bodies which are
important, unique, or sensitive ecologically, but
whose  water   quality,   as  measured  by  the
traditional parameters such as  dissolved oxygen
or pH, may not be particularly high.  Waters of
exceptional  ecological significance also include
waters whose characteristics cannot adequately be
described by  traditional   parameters  (such  as
wetlands and estuaries).

Antidegradation   implementation   procedures
address how States will ensure that the permits
and control programs meet water quality standards
and antidegradation policy requirements.

     General Policies

The Water Quality Standards Regulation allows
States to include in their standards State policies
and provisions  regarding water quality standards
implementation, such as mixing zones, variances,
and low-flow exemptions subject to EPA review
and  approval.   These  policies  and provisions
should be specified in the State's water  quality
standards document.  The State's rationale and
supporting documentation should be submitted to
EPA for review during the water quality standards
review and approval process.

          Mixing Zones

States  may, at their discretion,  allow  mixing
zones for dischargers. The States' water quality
standards should describe  the methodology for
determining the  location, size, shape,  outfall
design, and in-zone  quality  of mixing  zones.
Careful  consideration  must  be  given  to the
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                                                                                     Introduction
appropriateness  of a  mixing  zone  where  a
substance   discharged   is  bioaccumulative,
persistent,    carcinogenic,   mutagenic,    or
teratogenic.

          Low-Flow Provisions

State water quality standards should protect water
quality for  the designated  and  existing uses in
critical low-flow situations.  States may, however,
designate  a  critical  low-flow  below  which
numerical water quality  criteria do not apply.
When reviewing standards,  States should review
their low-flow provisions for conformance  with
EPA guidance.

          Water Quality Standards Variances

As an alternative to removing a designated use, a
State may wish to include a variance as part of a
water quality standard,  rather  than change the
standard across the  board, because  the State
believes that  the  standard ultimately  can  be
attained. By maintaining the standard rather than
changing it, the State will assure  that  further
progress is made in improving water quality and
attaining the standard.  EPA has approved State-
adopted variances in the past and will continue to
do so if:

•    the variance is included as part of the water
     quality standard;

•    the variance is subjected  to the same public
     review as  other  changes in water  quality
     standards;

•    the  variance   is  granted   based  on   a
     demonstration that meeting the standard is
     not feasible due to the presence of any of the
     same  conditions  as  if  the  State  were
     removing a designated  use (these conditions
     are listed  in  section 131.10(g)  of  the
     Regulation); and

•    existing uses will  be fully protected.
Water Quality Standards Review and Revision
Process - (Subpart C)

The Clean Water Act requires  States to hold a
public hearing(s)  to review their water  quality
standards at least once every 3  years and revise
them if appropriate.   After State water  quality
standards are officially adopted, a Governor or
designee submits the standards to the appropriate
EPA Regional Administrator for  review.   EPA
reviews the State standards to determine whether
the  analyses  performed  are  adequate.    The
Agency also evaluates whether the designated uses
and criteria are  compatible throughout the water
body and whether the downstream water  quality
standards are protected.   After  reviewing the
standards,  EPA makes  a  determination whether
the standards meet the requirements of the law
and EPA's water quality standards regulations. If
EPA disapproves a standard, the Agency indicates
what changes must be made for the standard to be
approved.  If a State fails to make  the required
changes, EPA promulgates a Federal standard,
setting forth  a new or  revised  water  quality
standard  applicable to the  State.

     State Review and Revision

States identify additions or revisions  necessary to
existing standards based on their 305(b) reports,
other available  water  quality  monitoring data,
previous   water  quality  standards reviews,  or
requests from industry, environmental groups, or
the public. Water quality standards  reviews and
revisions   may  take  many  forms,  including
additions to and  modifications in uses, in criteria,
in   the    antidegradation   policy,   in   the
antidegradation implementation  procedures, or in
other general policies.

Some States review  parts of their water  quality
standards  every year.   Other States perform a
comprehensive review  every  3 years.   Such
reviews are necessary because new scientific and
technical   data  may    become   available.
Environmental changes  over   time  may  also
necessitate the need for the review.
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     EPA Review

When States adopt new or revised WQS, the State
is required under CWA section 303 (c) to submit
such   standards   to  EPA   for  review  and
approval/disapproval.      EPA   reviews  and
approves/disapproves  the standards  based  on
whether the standards meet the requirements  of
the CWA.   As a  result of  the EPA  review
process, three actions are possible:

•    EPA approval (in whole or in part) of the
     submitted State water quality standards; or

•    EPA disapproval (in  whole or in part) of the
     submitted State water quality standards; or

•    EPA conditional  approval (in whole or  in
     part) of  the submitted State water  quality
     standards.

Revisions  to State  water quality  standards that
meet the requirements of the Act and the WQS
Regulation are  approved by the appropriate EPA
Regional Administrator. If only a partial approval
is made,  the  Region,  in notifying the State,
identifies the portions which  should be revised
(e.g., segment-specific requirements).

If the Regional Administrator determines that the
revisions submitted are not consistent with or do
not meet the requirements of the Act or the WQS
Regulation,    the   Regional   Administrator
disapproves  the standards within  90 days with a
written  notification  to the State.   The  letter
notifies the State  that the  Administrator  will
initiate promulgation proceedings if the State fails
to adopt and submit the necessary revisions within
90 days after notification.  The State water quality
standard   remains   in   effect,   even  though
disapproved by EPA, until the State revises it or
EPA promulgates a rule that supersedes the State
water quality standard.
Federally    Promulgated
Standards - (Subpart D)
Water    Quality
As discussed above, EPA may promulgate Federal
Water Quality  Standards.   Section 303  of the
Clean  Water Act permits  the Administrator to
promulgate Federal standards:

•    if a revised  or new water quality standards
     submitted by the State is determined by the
     Administrator not to be consistent with the
     applicable requirements of the Act; or

•    in  any  case  where  the  Administrator
     determines that a new or revised standard is
     necessary  to meet the requirements of the
     Act.

Federal promulgations are codified under Subpart
D of the Regulation.
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                                                                                   Introduction
      THE ROLE OF WQS IN THE WATER QUALITY MANAGEMENT
                                       PROGRAM
    State water quality standards play  a central
role in  a State's  water  quality management
program, which identifies the overall  mechanism
States use to integrate the  various Clean Water
Act quality control requirements into a coherent
management   framework.     This  framework
includes, for example:

•    setting  and  revising  standards  for  water
     bodies;

•    Water Quality  Assessments  to  determine
     attainment of designated uses;

•    CWA   section   305(b)   water   quality
     monitoring  to  provide information  upon
     which water quality-based decisions will be
     made,  progress  evaluated,  and  success
     measured;

•    calculating   total  maximum daily  loads
     (TMDLs), waste  load allocations (WLAs)
     for  point  sources  of pollution, and  load
     allocations (LAs) for nonpoint  sources of
     pollution;

•    developing a water quality management plan,
     certified by the Governor  and approved by
     EPA,  which   lists   the  standards   and
     prescribes the regulatory  and construction
     activities necessary to  meet the standards;

•    preparing section 305(b) reports  and lists
     that document the condition of the State's
     water quality;

•    developing, revising, and  implementing an
     effective  CWA section 319  program  and
     CZARA  section 6217 program to control
     NFS pollution;
•    making  decisions involving  CWA section
     401  certification  of  Federal  permits  or
     licenses; and

•    issuing NPDES permits for all point source
     discharges.   Permits  are  written to meet
     applicable water quality standards.

The Act provides the basis for two different kinds
of pollution control  programs.   Water quality
standards are the basis of the water quality-based
control  program.  The  Act  also provides  for
technology-based limits known as best available
treatment technology economically achievable for
industry and secondary  treatment for publicly
owned  treatment  works.     In  some  cases,
application of these technologically based controls
will  result in attaining water quality  standards.
Where such is not the case, the Act requires the
development of more stringent limitations to meet
the water quality standards.

Regulations,  policy,   and guidance  have been
issued  on  all the  activities  mentioned in this
section. Chapter 7 contains a brief discussion of
how  water quality standards  relate to many  of
these  activities  in   the   water   quality-based
approach  to  pollution control, but  additional
details on these other programs  is beyond  the
scope of this Handbook.  For further information,
see the EPA guidance documents referenced  in
chapter 7.
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                         FUTURE PROGRAM DIRECTIONS
Since the 1960's, the water science program has
moved from solving a limited set of problems in
a limited set of waters to one that  is solving a
broad range of complex problems in categories of
U.S. waters and addressing cross-media aspects of
water quality decisions. Initial efforts focused on
the more visible  sources  of pollution such  as
organic loadings, solids, oil, and grease, and then
shifted to toxics and more complex mixtures of
pollutants.

Developments  in  two  areas  have  significantly
affected  the scientific underpinnings  of the water
program. First is the science of risk assessment
used to  estimate risk to  human health and the
environment  from  exposure to  contaminants.
Second is our ability to measure pollutants in the
environment at an increasing  level of precision.
The evolution of methods and capabilities within
these two scientific disciplines  has  significantly
advanced the sophistication of scientific analyses
used to manage the water program.

As the water science program moves toward the
21st  Century,   we  must  provide   technical
information and  tools that  allow  States,  the
regulated  community,   and   the   public   to
understand and apply the methods,  criteria,  and
standards  to   environmental  systems.     This
includes   updating   science   and   adapting
technologies as appropriate to keep the foundation
of our  program  solid as well as employing or
modifying these approaches when appropriate for
new problems.

The CWA provides broad authority through its
goals and policy, such as:

     ...  to  restore  and  maintain the
     chemical,  physical,   and  biological
     integrity of the Nation's waters (section
     101(a)); and

     .  . . wherever attainable  , .  . water
     quality   which   provides   for   the
     protection and propagation  of  fish,
     shellfish, and wildlife ...  to protect
     the water of the United States (section
The breadth of this authority is also reflected in
specific EPA mandates such as those in section
304(a):

     [EPA]  shall develop and publish  .  . .
     criteria for water accurately reflecting
     the latest scientific knowledge  (A)  on
     the kind and extent of all identifiable
     effects  on health and welfare .  . . (B)
     on the  concentration and dispersion of
     pollutants  .  .  .   through  biological,
     physical,  and chemical processes; and
     (C)  the   effects  of  pollutants   on
     biological    community   diversity,
     productivity, stability . . . including
     eutrophication  and  rates  of  ...
     sedimentation  .  .  .  (CWA   section
     304(a)(l)); and

     [EPA]  shall develop and publish  .  . .
     information   (A)   on   the   factors
     necessary  to restore and maintain the
     chemical,   physical,  and   biological
     integrity  ...  (B)  on  the  factors
     necessary   for  the  protection  and
     propagation   of  shellfish,   fish,  and
     wildlife . . . and  to allow recreational
     activities  in and on the water  . .  .".)
     (304(a)(2))(CWA section 304(a)(2))

EPA  has  traditionally  focused  on  criteria  for
chemical  pollutants,  but  has  also developed
criteria  for  a limited number of physical  (e.g.,
color, turbidity, dissolves solids) and  biological
(bacteria,  "free  from"  nuisance aquatic  life)
parameters  (NAS/NAE, 1973; USEPA,  1976).
However, as  EPA's  water  quality protection
program has evolved, it has become apparent  that
chemical criteria alone, without the criteria for the
biological and physical/habitat components of
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                                                                                     Introduction
 water bodies, are insufficient to fully achieve the
 goals of the CWA.

 Future  directions  in the criteria  and standards
 program will focus on  providing scientific and
 technical tools to aid regional, State, and local
 environmental managers  in (1) implementating the
 standards  program,  and  (2)   developing  new
 science and  technology  that will  reduce human
 and ecological risks  resulting  from  exposure to
 unaddressed  contaminants  and  prevent pollution
 from point and nonpoint sources.

 Setting  future national program priorities will  be
 based on the consideration of risk assessment;
 statutory  and  court-mandated  obligations;  the
 expressed  needs of  regional,   State,  and local
 environmental  managers   and  the  regulated
 community;  and the  potential  effectiveness of a
 program   to   influence   real   environmental
 improvement.

 EPA will  be  developing methodologies and
 criteria  in areas beyond  the traditional chemical-
 specific  type criteria of  the  past.   Areas  of
 scientific examination and potential  regulatory
 controls include  criteria  to  protect  wildlife,
 wetlands, and sediment quality; biological criteria
 to better define desired biological communities in
 aquatic  ecosystems; and nutrient criteria.  EPA
 has also moved in the direction of  the physical
 and habitat components of water quality protection
 in other water quality programs.  For example,
 the CWA section 404(b)(l) Guidelines (40 CFR
 230)  evaluate physical  characteristics (such  as
 suspended  particulates, flow, and  hydroperiod),
 and habitat  components  (such as  food  web
 organisms, breeding/nesting areas,  and  cover).
 Implementation of these  various types  of criteria
 will be influenced by the environmental concerns
 in specific watersheds.

 To protect  human health, program emphasis will
 shift to focus on  the human  health impacts  of
pathogenic microorganisms in ambient waters that
cause illness in humans, and will address concerns
about the risk that contaminated fish may pose to
sensitive populations whose daily  diet includes
large quantities of fish.

In an expanded effort to protect ecology, there
will be  increasing emphasis  on the  watershed
approach  by assessing  all potential and actual
threats   to   a   watershed's  integrity.    Risk
assessment of the watershed and setting priorities
based on those risks  will  become increasingly
important in future program efforts in criteria and
standards as supporting elements to  the watershed
approach.

Over the next few years,  there  will be more
emphasis on developing effective risk reduction
strategies that include both traditional and non-
traditional controls and approaches.

Future program directions in criteria development
and  then adoption and implementation of water
quality standards will be based on the principle of
ecological  and  human   health risk  reduction
through sound and implementable science.

Endangered Species Act

An important consideration  in future criteria and
standards development will be the conduct of the
consultation provisions of the Endangered Species
Act  (ESA)  and  the implementation of  any
revisions  to  standards   resulting   from those
consultations.   Section  7  of the Endangered
Species   Act requires  all Federal  agencies,  in
consultation with the Fish and Wildlife  Service
and  the  National Marine Fisheries Service  (the
Services) to  assure  that any action authorized,
funded, or implemented by a Federal agency does
not jeopardize  the existence of endangered  or
threatened species or result  in the destruction  or
adverse modification of their critical habitat. The
definition of a Federal action is very broad and
encompasses virtually   every  water  program
administered by EPA.

The  responsibility  for ensuring that consultation
occurs with the Services lies with EPA, although
in fulfilling  the  requirements a   non-Federal
representative may be designated  for informal
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Water Quality Standards Handbook - Second Edition
consultation. (Note:  Consultation may be formal
or informal; the latter form is the most prevalent.)
Protection of threatened and endangered species
and their habitat is a critical national priority, and
the  criteria  and  standards  programs   can  be
effective tools to meet this national priority. All
aspects  of  standards,  including  aquatic  life
criteria, uses, antidegradation, and implementation
actions related to the standards are subject to
consultation.   All future revised aquatic life
criteria, sediment, wildlife, and biological criteria
will be subject to the consultation requirements as
will their adoption into enforceable standards.

To form  an effective partnership between the
Services and EPA in  creating a framework for
meeting the responsibilities under section 7 of the
Endangered  Species  Act and applicable  EPA
regulations, the Services and EPA  entered into a
joint  guidance  agreement  in  July  1992 (see
Appendix  F).   This  agreement sets forth the
procedures to be followed by the Services and
EPA to assure  compliance with  section 7 of the
ESA in the development of water quality criteria
published pursuant to section 304(a) of the CWA
and the adoption of water quality standards under
section 303(c).  This agreement also indicated that
the regional  and field offices of  EPA  and the
Services could establish sub-agreements specifying
how they  would implement the joint  national
guidance.

During  the preparation  of  this second  edition
Handbook, the Services and EPA initiated a work
group  to  develop  a   more  extensive  joint
agreement.  This  group was  charged with the
responsibility  of  reviewing   the   July   1992
agreement, making appropriate revisions  to the
water quality criteria and standards sections, and
adding a new section discussing the consultation
procedures to be followed for the NPDES permit
program.    When  the  revised  agreement  is
approved  by the Agencies, it  will  replace the
agreement included in this Handbook as Appendix
F.

Both  the  current agreement and the proposed
revision seek to ensure  a  nationally consistent
consultation process that allows  flexibility to deal
with site-specific issues  and to  streamline the
process to minimize the regulatory burden. The
overriding goal is  to provide for the protection
and support of the recovery of threatened and
endangered species and the  ecosystems on which
they depend.
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                                                             Chapter 1 - General Provisions
                                CHAPTER 1

                          GENERAL PROVISIONS

                          (40 CFR 131 - Subpart A)

                              Table of Contents

1.1  Scope - 40 CFR 131.1	1-1

1.2  Purpose - 40 CFR 131.2  	1-1

1.3  Definitions - 40 CFR 131.3	1-1
     1.3.1     States	1-1
     1.3.2     Waters of the United States  	1-2

1.4  State Authority - 40 CFR 131.4	1-2

1.5  EPA Authority - 40 CFR 131.5  	1-3

1.6  Requirements for Water Quality Standards Submission - 40 CFR 131.6	1-4

1.7  Dispute Resolution Mechanism - 40 CFR 131.7  	1-4
     1.7.1     Responsibility Is With Lead EPA Regional Administrator	1-5
     1.7.2     When  Dispute Resolution May Be Initiated	1-5
     1.7.3     Who May Request Dispute Resolution and How	1-6
     1.7.4     EPA Procedures in Response to Request  	1-6
     1.7.5     When  Tribe and State Agree to a Resolution   	1-6
     1.7.6     EPA Options for Resolving the Dispute	1-7
     1.7.7     Time Frame for Dispute Resolution   	1-8

1.8  Requirements for Indian Tribes To Qualify for the WQS Program - 40 CFR 131.8 .. 1-9
     1.8.1     Criteria Tribes Must Meet  	1-9
     1.8.2     Application for Authority To Administer the Water Quality Standards
              Program  	1-13
     1.8.3     Procedure Regional  Administrator Will Apply	 1-14
     1.8.4     Time Frame for Review of Tribal Application   	 1-16
     1.8.5     Effect  of Regional Administrator's Decision  	 1-16
     1.8.6     Establishing Water Quality Standards on Indian Lands	 1-16
     1.8.7     EPA Promulgation of Standards for Reservations  	 1-18

1.9  Adoption of Standards for Indian Reservation Waters	 1-18
     1.9.1     EPA's Expectations  for Tribal  Water Quality Standards	 1-18
     1.9.2     Optional Policies	1-19
     1.9.3     Tribal  Submission and EPA Review   	 1-19
     1.9.4     Regional Reviews   	1-19

Endnotes  	1-21

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                                                                    Chapter 1 - General Provisions
                                       CHAPTER 1
                                GENERAL PROVISIONS
        Scope - 40 CFR 131.1
The Water Quality Standards Regulation (40 CFR
131) describes State requirements and procedures
for developing, reviewing, revising, and adopting
water  quality  standards  (WQS),   and  EPA
requirements  and  procedures  for   reviewing,
approving, disapproving, and promulgating water
quality standards as authorized by section 303(c)
of the Clean Water Act.  This Handbook serves
as guidance for implementing the Water Quality
Standards Regulation and its provisions.
        Purpose - 40 CFR 131.2
A water quality standard defines the water quality
goals for a water body,  or portion thereof, by
designating the use or uses  to be made of the
water, by setting criteria necessary to protect the
uses,  and by  protecting  water quality  through
antidegradation provisions.   States adopt water
quality  standards to  protect public health or
welfare, enhance the quality of water, and serve
the purposes of the Clean Water  Act (the Act).
"Serve the purposes of the Act" means that water
quality standards should:

•  wherever attainable, achieve a  level  of water
   quality that  provides for the  protection  and
   propagation of fish, shellfish, and wildlife, and
   for recreation in and on the water,  and  take
   into consideration the use and value of public
   water supplies, and agricultural, industrial, and
   other purposes, including navigation  (sections
   101(a)(2) and 303(c) of the Act); and

•  restore and maintain the chemical, physical,
   and biological integrity of the Nation's waters
   (section 101(a)).
      CLEAN WATER ACT GOALS

   • Achieve  a level of water quality that
     provides for the protection and propaga-
     tion of fish, shellfish, and wildlife, and
     for recreation in  and on  the  water,
     where attainable.

   • Restore  and  maintain the  chemical,
     physical, and biological integrity of the
     Nation's  waters.
These  standards  serve  dual  purposes:  They
establish the  water  quality goals  for a  specific
water body, and they serve as the regulatory basis
for establishing  water  quality-based  treatment
controls   and   strategies   beyond   the
technology-based levels of treatment required by
sections 301 (b) and 306 of the Act.
        Definitions - 40 CFR 131.3
Terms used  in the Water  Quality  Standards
Regulation are defined in section  131.3  of the
regulation. These definitions, as well as others
appropriate  to  the  water  quality  standards
program,  are  contained in the glossary of this
Handbook. No additional guidance is necessary
to  explain  the  definitions;  however,   some
background  information  on  the definitions of
"States" and "waters of the Uniied States" may be
helpful.

1.3.1 States

Indian Tribes  may now  qualify for the water
quality standards and 401  certification programs.
The February  4, 1987, Amendments to the Act
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added  a  new  section  518  requiring  EPA  to
promulgate regulations specifying how the Agency
will treat qualified Indian Tribes as States for the
purposes  of,  the  section  303  (water quality
standards)   programs,   the   section   401
(certification) programs, and other programs.  On
December 12,  1991,  the  EPA  promulgated
amendments to Subpart A of the Water Quality
Standards Regulation in response to the CWA
section  518 requirements  (see 56 F.R. 64893).
These  amendments  modified the definition  of
States by adding the phrase  "... and  Indian
Tribes that EPA determines qualify for treatment
as States for purposes of water quality standards."

1.3.2 Waters of the United States

Section  303 (c) of the CWA  requires States  to
adopt water  quality standards  for  "navigable
waters," which are defined at section  502(7) of
the Act as "waters of the United States."  The
Water Quality Standards Regulation contains  no
definition of  "waters  of the United States,"
although this term is used in the definition  of
"water quality standards."   The phrase "waters of
the United States" has been defined elsewhere in
Federal regulations (e.g., in regulations governing
the  National  Pollutant  Discharge  Elimination
System  (NPDES) and section 404 programs (40
CFR  sections   122.2,   230.3,  and   232.3,
respectively).   This definition appears  in the
glossary  of  this  Handbook and  is  used  in
interpreting the phrase "water quality standards."

The definition of  "waters  of  the United States"
emphasizes protection of a broad range of waters,
including  interstate and intrastate  lakes, streams,
wetlands,  other  surface waters,  impoundments,
tributaries of waters, and the territorial seas.

EPA believes  that  some  States may  not  be
providing the same protection to wetlands that
they provide to other surface waters.  Therefore,
EPA wishes to emphasize that wetlands deserve
the same protection under water quality standards.
For more information on the application of water
quality standards to wetlands,  see Appendix  D of
this Handbook.
   WATERS OF THE UNITED STATES
         Interstate/intrastate lakes
         Streams
         Wetlands
         Other surface waters
         Impoundments
         Tributaries of waters
         Territorial seas
Concerns have been raised regarding applicability
of water quality standards to riparian areas other
than riparian wetlands.  "Riparian areas" are areas
in a stream's floodplain with life characteristic of
a  floodplain.    Wetlands  are  often  found  in
portions of riparian areas.  The Clean Water Act
requires States  to  adopt  water quality standards
only for "waters of the  United  States," such as
wetland portions of riparian areas that meet the
regulatory definition.  Of course, States may, at
their discretion, choose  to adopt water quality
standards  or other mechanisms  to  protect other
riparian areas.
         State Authority - 40 CFR 131.4
States (including Indian Tribes qualified for the
purposes   of  water  quality  standards)   are
responsible   for  reviewing,  establishing,   and
revising water quality  standards.   Under section
510 of the Act, States may develop water quality
standards  more  stringent than required by the
Water Quality Standards Regulation.

Under section 401  of  the Act, States also  have
authority to issue water quality certifications for
federally permitted or  licensed activities.    This
authority   is  granted  because   States   have
jurisdiction  over their  waters and can influence
the design  and  operation  of projects  affecting
those waters.  Section 401 is intended to ensure
that  Federal permits and licenses comply  with
applicable water quality requirements, including
State water quality standards, and applies to all
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                                                                       Chapter 1 - General Provisions
 Federal agencies that grant a license or permit.
 (For example, EPA-issued  permits for  point
 source   discharges   under   section  402  and
 discharges  of dredged  and fill material under
 section 404 of the Clean Water Act; permits for
 activities in  navigable  waters  that  may affect
 navigation under sections 9 and 10 of the Rivers
 and Harbors Act (RHA); and licenses required for
 hydroelectric  projects issued under  the  Federal
 Power  Act).    Section  401  certifications  are
 normally  issued  by  the State  in  which  the
 discharge originates.

 States   may   deny    certification,   approve
 certification,   or   approve   certification  with
 conditions. If the State denies certification,  the
 Federal  permitting   or  licensing  agency   is
 prohibited from issuing  the  permit or  license.
 Certifications   are  subject  to  objection  by
 downstream States where the downstream State
 determines that the  proposed  activity  would
 violate  its water quality standards.  [For more
 information on the 401 certification process, refer
 to Wetlands and 401  Certification: Opportunities
for States and Eligible  Indian  Tribes (USEPA,
 1989a).]
         EPA Authority - 40 CFR 131.5
Under section 303(c) of the Act, EPA is to review
and to approve or disapprove State-adopted water
quality  standards.     This  review  involves  a
determination of whether:

•  the State has adopted water uses consistent
   with the requirements of the Clean Water Act;

•  the State has  adopted criteria that protect the
   designated water uses;

•  the State has followed its legal procedures for
   revising or adopting standards;

•  the State standards that do not include the uses
   specified in section 101(a)(2) of the Act are
   based upon appropriate technical and scientific
   data and analyses;  and
•  the State  submission meets the requirements
   included in section 131.6 of the Water Quality
   Standards Regulation.

EPA reviews State water  quality standards to
ensure that the standards meet the requirements of
the Clean  Water Act.  If EPA  determines  that
State water quality standards are consistent with
the five factors  listed above, EPA approves the
standards.    EPA disapproves the  State  water
quality  standards  and may promulgate Federal
standards  under section 303(c)(4) of the Act if
State-adopted standards are not consistent with the
factors  listed above.   Section 510 of the  Act
provides that the States are  not  precluded from
adopting  requirements  regarding  control   or
abatement   of  pollution   as   long   as   such
requirements  are  not  less  stringent  than  the
requirements of the Clean  Water  Act.   The
Agency is  not authorized to disapprove a State
water  quality standard  on  the  basis  that EPA
considers the standard to be too stringent.  EPA
may also promulgate a  new  or revised standard
where necessary to meet the requirements of the
Act.  In certain cases, EPA may conditionally
approve  a  State's  standards.    A  conditional
approval is appropriate only:

•  to correct minor deficiencies in  a State's
   standards; and

•  when a State agrees to a specific time schedule
   to make the corrections in as  short a time as
   possible.  Section 6.2 provides guidance on
   conditional approvals.
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EPA also has the authority to issue  section 401
certification where a State or interstate agency has
no authority to do so.
        Requirements  for  Water  Quality
        Standards Submission - 40 CFR 131.6
The following elements must be included in each
State's water quality standards subniittal  to EPA
for review:

•  use designations consistent with the provisions
   of sections 101(a)(2) and 303(c)(2) of the Act;

•  methods  used  and  analyses conducted  to
   support water quality standards revisions;

•  water quality criteria sufficient to protect the
   designated uses, including criteria for priority
   toxic pollutants and biological criteria;

•  an antidegradation policy and implementation
   methods consistent with section 131.12 of the
   Water Quality Standards Regulation;

•  certification by the State  Attorney General or
   other appropriate  legal authority within the
   State that the water quality standards were duly
   adopted pursuant to State law; and

•  general information  to  aid  the Agency in
   determining the  adequacy of the  scientific
   bases of the standards that do not include the
   uses specified in section  101(a)(2) of the Act
   as  well as information  on general  policies
   applicable to State standards that may affect
   their application and implementation.

EPA may also request additional information from
the State to aid in determining the adequacy of the
standards.
         Dispute Resolution  Mechanism - 40
         CFR 131.7
Section 518 of the Act requires EPA to establish
a   "mechanism   for  the  resolution  of  any
unreasonable consequences  that may arise as a
result of differing water  quality standards that
may be set by States and Indian Tribes located on
common bodies  of water."    EPA's  primary
responsibility in response to this requirement is to
establish a practical procedure  to  address  and,
where possible,  resolve such disputes as  they
arise.   However,  the Agency's  authority  is
limited.

For example, EPA does not believe that section
518 grants EPA authority to override section 510
of the Act.  EPA believes that the  provisions of
section 510 would apply  to  Indian Tribes that
qualify for treatment as States.   Section  518(e)
and its accompanying legislative history suggest
that Congress intended for section 510 to apply to
Tribes as well as States. Were Tribes prohibited
from establishing standards more stringent than
minimally approvable by  EPA,  there  would  be
little need for the dispute resolution mechanism
required by section 518(e)(2).   Therefore,  EPA
does not believe that section 518 authorizes the
Agency to disapprove  a  State  or  Tribe  water
quality standard  and promulgate a  less  stringent
standard as  a means of resolving  a State/Tribe
dispute.

EPA also believes there are strong policy reasons
to allow Tribes to set any water quality standards
consistent  with  the  Water  Quality  Standards
Regulation.   First,  it puts Tribes and States  on
equal footing with  respect to standards setting.
There is no indication that Congress intended to
treat Tribes as "second class" States under the
Act.   Second,  treating  Tribes as  essentially
equivalent to States is consistent with EPA's 1984
Indian Policy.  Third, EPA believes it would be
unfeasible to require Tribes to adopt "minimum"
standards allowed under Federal law.   EPA has
no procedures in place for defining  a "minimum"
level of standards  for Indian  Tribes.    EPA
evaluates only whether the standards are stringent
enough, not how much more stringent than any
Federal minimum.
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                                                                      Chapter 1 - General Provisions
 1.7.1  Responsibility   Is   With  Lead  EPA
       Regional Administrator

 EPA's role in dispute resolution  is to work with
 all parties  to the dispute in an effort to reach an
 agreement that resolves the dispute. The Agency
 does not automatically support the Indian position
 in  all disputes  over  water  quality  standards.
 Rather, EPA employees serving  as mediators or
 arbitrators will serve outside the  normal Agency
 chain of command and are expected to act in a
 neutral fashion.

 The lead EPA  Regional Administrator will  be
 determined using OMB Circular A-95.  The lead
 Region is  expected to  enlist  the  aid  of other
 affected  Regions in routine dispute  resolution.
 EPA Headquarters will also oversee the process to
 ensure that the interests of all affected Regions
 are represented.  Designation as the lead Region
 for resolving  a dispute  or programmatic issues
 within EPA does not mean that the lead Region
 has  a  license  to  act  unilaterally.     Rather,
 designation  as   lead  Region   assigns   the
 responsibility to ensure that the process leading to
 a decision is fair to all parties.

 The Regional Administrator may include other
 parties besides Tribes and  States in the dispute
 resolution process.  In some cases, the  inclusion
 of permittees or landowners subject to  nonpoint
 source restrictions may be needed to arrive at a
 meaningful resolution of the dispute.  However,
 only the Tribe  and State  are in a position  to
 implement a change in water quality standards and
 are,  thus,  the only "necessary"  parties  hi  the
 dispute resolution.

 1.7.2 When  Dispute  Resolution  May  Be
      Initiated

 The regulation establishes conditions under which
 the Regional Administrator would be responsible
 for initiating a dispute resolution action.   Such
actions would be initiated where, in the judgment
of the Regional Administrator:

•  there are unreasonable consequences;
 •  the dispute is  between a State and a  Tribe
   (i.e., not between a Tribe and another Tribe or
   a State and another State);

 •  a reasonable effort has been made to resolve
   the   dispute   before   requesting   EPA
   involvement;

 •  the requested relief is  within the authority of
   the Act (i.e., not a request to replace State or
   Tribe standards that comply  with the Act with
   less stringent Federal standards);

 •  the differing standards  have  been adopted
   pursuant to State or Tribe law and approved by
   EPA;

 •  a valid  written request for EPA  involvement
   has   been   submitted  to   the  Regional
   Administrator by the State or Tribe.

 Although the Regional Administrator may decline
 to initiate a dispute resolution action based on any
 of the above  factors, EPA is willing to discuss
 specific  situations.   EPA is  also  willing  to
 informally   mediate  disputes  between  Tribes
 consistent  with the  procedures  for mediating
 disputes between States  (see 48 F.R. 51412).

 The  regulation  does not  define  "unreasonable
 consequences" because:

 •  it would be  a  presumptuous and unjustified
   Federal intrusion into local and State concerns
   for EPA   to define  what  an  unreasonable
   consequence might be as a basis for a national
   rule;

 •  EPA does  not  want  to unnecessarily  narrow
   the scope of problems to be addressed by the
   dispute resolution mechanism; and

 •  the  possibilities of what might constitute an
   unreasonable consequence are so numerous as
   to defy a logical regulatory requirement.

Also,  the  occurrence of  such "unreasonable"
consequences  is  dependent   on  the  unique
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circumstances associated  with the dispute.   For
example,   what   might   be   viewed   as   an
unreasonable consequence on a stream segment in
a large, relatively unpopulated, water-poor area
with a single discharge would  likely be viewed
quite differently in or near an area characterized
by  numerous  discharges  and/or  large  water
resources.    The  Regional Administrator  has
discretion  to  determine  when   consequences
warrant initiating  a dispute resolution action.

1.7.3 Who May  Request Dispute Resolution
      and How

Either the  State or the Tribe may request EPA
involvement in the dispute. The requesting party
must include the  following items in its written
request:

•  a  statement  describing  the  unreasonable
   consequences;

•  description of the actions taken to resolve the
   dispute before  requesting EPA involvement;

•  a statement  describing  the  water  quality
   standards  provision (such  as  the particular
   criterion) that has resulted in the unreasonable
   consequences;

•  factual  data  substantiating   the  claim  of
   unreasonable consequences; and

•  a statement of relief sought (that is, the desired
   outcome of the dispute resolution action).
1.7.4 EPA Procedures in Response to Request

When the  Regional Administrator decides that
EPA involvement is  appropriate (based on  the
factors discussed in section  1.7.2,  above),  the
Regional Administrator will notify the parties in
writing that EPA dispute resolution action is being
initiated and  will solicit their written response.
The Regional  Administrator  will  also   make
reasonable  efforts to ensure that other interested
individuals or groups have notice of this action.
These "reasonable efforts" will include, and  are
not limited to, the following:

•  written notice to responsible Indian and State
   Agencies and other affected Federal Agencies;

•  notice to the specific individual or entity that
   is claiming that an unreasonable consequence
   is resulting  from differing  standards having
   been adopted for a common water body;

•  public notice in local newspapers, radio, and
   television, as appropriate;

•  publication in trade journal newsletters;  and

•  other appropriate means.

1.7.5 When Tribe  and State  Agree   to  a
      Resolution

EPA encourages Tribes and States to resolve  the
differences without EPA involvement and  to
consider jointly  establishing a  mechanism  to
resolve disputes before such disputes arise. The
Regional  Administrator  has responsibility   to
review  and either  approve  or disapprove  the
Tribe-State agreement.  Section 518(d) provides
that Tribe-State agreements in general for water
quality management are to be approved by EPA.
As a  general  rule, EPA  will  defer  to  the
procedure   for  resolving   disputed   jointly
established by the Tribe and State so long as the
procedure and the end result are consistent with
the provisions  of the CWA  and Water Quality
Standards Regulation.
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                                                                     Chapter 1 - General Provisions
 1.7.6  EPA Options for Resolving the Dispute

 The dispute resolution mechanism included in the
 final  "Indian  Rule"  provides  EPA  Regional
 Administrators with several alternative courses of
 action.     The   alternatives  are  mediation,
 non-binding arbitration,  and a default procedure.

 The first technique, mediation, would allow the
 Regional  Administrator to  appoint  a  mediator
 whose primary function would be to facilitate
 discussions between the  parties with the objective
 of arriving  at a State/Tribe agreement or other
 resolution acceptable to the parties. The mediated
 negotiations could be informal or formal, public
 or private.  The mediator could also establish an
 advisory group, consisting of representatives from
 the  affected  parties, to  study the problem  and
 recommend an appropriate resolution.

 The second  technique,  non-binding  arbitration,
 would require  the Regional Administrator to
 appoint an arbitrator (or arbitration panel) whose
 responsibilities  would   include  gathering   all
 information pertinent to the dispute,  considering
 the factors listed in the  Act,  and recommending
 an appropriate solution.  The parties would not be
 obligated, however, to abide by the arbitrator's or
 arbitration  panel's decision.   The arbitrator or
 arbitration panel would be responsible for issuing
 a written recommendation to all parties and the
 Regional Administrator.  Arbitrators or arbitration
 panel members who are EPA employees would be
 allowed to operate independently from the normal
 chain  of  commend  within the  Agency  while
 conducting the arbitration process. Arbitrators or
 arbitration panel members would not be allowed
 to have ex pane communication pertaining to the
 dispute, except  that they would  be  allowed to
 contact EPA's Office of the General Counsel for
 legal advise.

 EPA has also provided  for a dispute resolution
 default procedure to be used where one or more
parties refuse  to participate  in mediation  or
arbitration.  The default procedure will be used
only as a last resort, after all other  avenues of
resolving the dispute have been exhausted. This
 dispute resolution technique would be similar to
 arbitration,  but has been included as a separate
 Regional Administrator option because arbitration
 generally  refers to a process whereby all parties
 participate voluntarily.

 The default procedure  simply  provides for  the
 Agency to review available information and to
 issue a recommendation for resolving the dispute.
 EPA's recommendation in  this situation  would
 have no enforceable impact.  The Agency hopes
 that public presentation  of its position will result
 in either  public pressure  or reconsideration  by
 either  affected  party  to   continue  resolution
 negotiations.   Any   written  recommendation
 resulting from this procedure would be provided
 to all parties involved in the dispute.

 EPA envisions a number of possible outcomes
 that, individually or in combination, would likely
 resolve most of the disputes that would arise.
 These actions might include, but are not limited
 to, the following:

 •  a State or Tribe agrees to revise the limits of
   a permit to ensure  that downstream  water
   quality standards are met;

 •  a State or Tribe agrees to permanently remove
   a use (consistent with 40 CFR 131.10(g));

 •  a State or Tribe issues a variance  from water
   quality standards for a particular discharge;

 •  a permittee  or landowner agrees  to provide
   additional water pollution control;

 •  EPA assumes  permit-issuing authority for a
   State or Tribe and re-issues a permit to ensure
   that downstream water quality standards are
   met; or

 •  EPA  promulgates   Federal  water  quality
   standards where a State or Tribe standard does
   not meet the requirements of the Act.

In  some  cases (last  example,  above),  EPA
recognizes that the Agency will have to act to
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resolve the dispute, An example would be where
a National Pollutant Discharge Elimination System
(NPDES) permit for an upstream discharger does
not provide for the attainment of the water quality
standards for a downstream jurisdiction.   The
existing  NPDES  permitting   and  certification
processes under the  Act may be used by  the
downstream   jurisdiction   to   prevent   such
situations.    Today's  rule  does  not  alter or
minimize  the  role  of  these   processes   in
establishing appropriate permit limits to  ensure
attainment of water quality standards. States and
Tribes are  encouraged to  participate  in these
permitting and certification processes rather than
wait for unreasonable consequences to occur.

In these cases, EPA believes that the Agency has
authority to object to the upstream NPDES permit
and, if necessary, to assume permitting authority.
This authority was upheld in a case in which EPA
assumed  authority to  issue a permit for a North
Carolina discharge that, among other factors, did
not meet Tennessee's downstream  water  quality
standards.1

Mediators and arbitrators may be EPA employees,
employees of other Federal agencies,  or other
individuals   with  appropriate   qualifications.
Because  of resource constraints, EPA anticipates
that  mediators and arbitrators  will generally be
EPA  employees   rather   than   consultants.
Employees from other Federal agencies  would be
selected  where appropriate,   subject  to their
availability.    EPA  intends for mediators and
arbitrators  to  conduct  the dispute resolution
mechanism in a fair  and impartial manner, and
will select individuals who have not been involved
with   the  particular  dispute.    Members  of
arbitration panels will be selected by the Regional
Administrator in consultation with the parties.  In
some  cases,  such panels may consist of one
representative from each party to the dispute plus
one  neutral panel member.    Implicit  in  the
regulation  is  the sense  that  mediators and
arbitrators  will   act  fairly   and   impartially.
Although  not  specifically   covered   in  the
regulation,  EPA believes it is well within the
Regional Administrator's power  to remove  any
mediator or arbitrator for any reason  (including
showing bias or unfairness or taking illegal or
unethical actions).

Arbitrators and arbitration panel members shall be
selected  to include  only  individuals  who  are
agreeable   to  all   affected   parties,   are
knowledgeable concerning  the  water  quality
standards program requirements,  have a basic
understanding of  the  political  and  economic
interests of Tribes, and will fulfill the duties fairly
and  impartially.   These requirements  are  not
applicable to mediators.  EPA did not provide for
State or Tribe approval of mediators because EPA
believes that  such an  approval  process would
provide  too great an opportunity  to  delay the
initiation of the mediation process and because the
role of the mediator is limited  to acting  as a
neutral facilitator.  There is no prohibition against
the Regional Administrator consulting with the
parties  regarding  a mediator;  there  is just no
requirement to do  so.

Where one of the  parties to the dispute believes
that an  arbitrator has recommended an action to
resolve  the dispute which is not authorized by the
Act, the regulation allows the party to appeal the
arbitrator's   decision   to   the   Regional
Administrator.  Such requests must be in writing
and must include a statement of the statutory basis
for altering the arbitrator's recommendation.

1.7.7 Time Frame for Dispute Resolution

The regulation does not  include  a fixed  time
frame for resolving disputes.  While EPA intends
to proceed as quickly as possible and to encourage
parties to the dispute to resolve it quickly and to
establish  informal time frames, the  variety of
potential disputes to be resolved would appear to
preclude EPA from specifying a single regulatory
time limit.  EPA believes it  is better to obtain a
reasonable  agreement  or  decision  than  to
arbitrarily establish a time frame within which an
agreement or decision must be made.
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                                                                      Chapter 1 - General Provisions
         Requirements  for  Indian Tribes  To
         Qualify for the WQS  Program - 40
         CFR 131.8
Consistent with  the  statutory  requirement  of
section 518  of  the  Act,  the  Water  Quality
Standards Regulation  establishes procedures by
which an  Indian Tribe may qualify for the water
quality standards  and section 401  certification
programs. Section  131.8 of the Water Quality
Standards Regulation is  intended to ensure that
Tribes  treated  as  States   for  standards   are
qualified,   consistent  with   Clean  Water  Act
requirements, to conduct a  standards  program
protective of public  health and the environment.
The procedures are not intended to act as a
barrier to tribal program assumption.  For the
section 401   certification  program,   131.4(c)
establishes that where EPA  determines  that a
Tribe is qualified for the water quality standards
program,  that Tribe would, without further effort
or submission of information, also qualify  for the
section 401 certification program.

Section 518 authorizes EPA to qualify a Tribe for
programs  involving water resources that are:

   . .  . held  by an Indian Tribe, held by the
   U.S. in trust for Indians, held by a member
   of an Indian Tribe if such property interest
   is subject to a trust restriction on alienation,
   or otherwise within the borders of an Indian
   reservation ....
Tribes  are   limited   to   obtaining   program
authorization only for water resources within the
borders of the reservation over which they possess
authority to regulate water quality.  The meaning
of the term  "reservation"  must, of course, be
determined in  light of statutory law  and with
reference  to  relevant  case law.   EPA considers
trust  lands formally  set apart  for the use of
Indians to be "within a reservation" for purposes
of section 518 (e)(2), even if they have not been
formally  designated  as  "reservations."2   This
means it  is the status and use of the land that
determines if it  is to be considered  "within a
reservation" rather than the label attached to it.
EPA believes that it was the intent of Congress to
limit   Tribes  authority  to  lands  within   the
reservation.  EPA bases this conclusion, in part,
on the definition of "Indian Tribe" found in CWA
section 518(h)(2). EPA also does not believe that
section 518(e)(2) prevents EPA from recognizing
tribal authority over non-Indian  water resources
located within  the reservation if the Tribe can
demonstrate (1)  the requisite authority over such
water resources, and (2) the authority to regulate
as necessary  to protect the public health,  safety,
and welfare of its tribal members.

1.8.1  Criteria Tribes Must Meet

New section 131.8 of the Water Quality Standards
Regulation includes   the  criteria   Tribes   are
required to meet to be authorized to administer
the water  quality standards and 401 certification
programs.  These criteria are provided in section
518 of the Act.  The Tribe must:
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•  be federally recognized;

•  carry out substantial governmental duties and
   powers over a Federal Indian reservation;

•  have appropriate authority  to  regulate  the
   quality of reservation waters; and

•  be  reasonably  expected  to be capable  of
   administering the standards program.

The  first  criterion requires the  Tribe  to  be
recognized by the  Department of the Interior.
The Tribe may address this requirement by stating
that  it  is included on the  list  of  federally
recognized Tribes  published periodically  by the
Department of the Interior, or by submitting other
appropriate  documentation  (e.g.,  the  Tribe is
federally recognized but not yet included on the
Department of the Interior list).

The second criterion requires the Tribe to have a
governing body  that is  carrying out substantial
governmental duties and powers.   EPA defines
"substantial governmental duties and powers" to
mean  that the  Tribe  is currently performing
governmental  functions  to  promote the  health,
safety, and  welfare of  the  affected population
within a defined geographical area. Examples of
such functions include, but are not limited to, the
power to tax, the power of eminent domain,  and
police power.     Federal  recognition  by  the
Department  of the  Interior does not,  in  and of
itself, satisfy this criterion.  Tribes must submit a
narrative statement describing  the form of tribal
government,  describing  the types of essential
governmental functions currently performed, and
identifying the sources of authorities to perform
these functions (e.g., tribal constitutions, codes).

The third criterion, concerning tribal authority,
means that EPA may authorize an Indian Tribe to
administer the water  quality standards program
only where  the Tribe already  possesses and can
adequately demonstrate  authority to manage and
protect water resources within  the reservation
borders.  The Clean Water Act authorizes use of
existing tribal regulatory authority for managing
EPA  programs,  but  the Act  does  not  grant
additional authority to Tribes.  EPA recognizes
that, in general, Tribes  possess the authority to
regulate activities affecting water quality on the
reservation.    The  Agency  does not  believe,
however, that it is appropriate to recognize tribal
authority and approve tribal administration of the
water quality standards program in the absence of
verifying documentation.  EPA will not delegate
water quality standards  program  authority  to a
Tribe unless the Tribe adequately shows that it
possesses the requisite authority.

EPA does not read the Supreme Court's decision
in Brendale3 as preventing EPA from recognizing
Tribes' authority to regulate water quality on fee
lands within the reservation, even if section 518
is not an express delegation of authority.  The
primary  significance of Brendale is  its result,
fully consistent with Montana v.  United States,4
which previously had held:

   To be sure, Indian tribes retain inherent
   sovereign power to exercise some forms of
   civil jurisdiction over non-Indians on their
   reservations, even on non-Indian fee lands.
   A tribe may regulate ... the  activities of
   non-members   who   enter  consensual
   relationships with the tribe or its members,
   through  commercial   dealing, contracts,
   leases, or other arrangements.  ... A tribe
   may also retain inherent power to exercise
   civil authority  over  the conduct of non-
   Indians on fee lands  within its reservation
   when that conduct threatens or  has some
   direct effect on  the political integrity, the
   economic security, or the health or welfare
   of the tribe.

The ultimate decision regarding  tribal authority
must be made on a Tribe-by-Tribe basis, and EPA
has  finalized the proposed process for making
those determinations. EPA sees no reason in light
of Brendale to assume that Tribes  would be per se
unable to demonstrate authority over water quality
management on fee lands  within reservation
borders.  EPA believes that as a general matter
there are substantial legal and factual reasons to
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                                                                       Chapter 1 - General Provisions
 assume  that  Tribes ordinarily  have  the legal
 authority to regulate surface water quality within
 a reservation.

 In evaluating whether  a Tribe has authority  to
 regulate a particular activity on land owned in fee
 by nonmembers but located within a reservation,
 EPA will examine the Tribe's authority in light of
 the evolving case law as reflected in Montana and
 Brendale.   The  extent of such tribal authority
 depends on the effect of that activity on the Tribe.
 As discussed above, in the absence of a contrary
 statutory policy,   a Tribe   may  regulate  the
 activities of non-Indians on fee  lands  within its
 reservation when those  activities threaten or have
 a direct effect on the political  integrity,  the
 economic security,  or the health or welfare of the
 Tribe.

 The Supreme Court, in  recent cases, has explored
 several options to  ensure  that the impacts upon
 Tribes of the activities of non-Indians on fee land,
 under the  Montana test, are  more than  de
 minimis, although  to  date  the  Court has  not
 agreed,  in  a  case on  point,   on   any  one
 reformulation of the test.   In  response to  this
 uncertainty, the Agency will apply, as an interim
 operating rule, a formulation of the standard that
 will require a showing  that the potential impacts
 of regulated activities on the Tribe are serious and
 substantial.

 The  choice  of  an   Agency   operating  rule
 containing this standard  is taken solely as a matter
 of prudence in light of judicial  uncertainty  and
 does  not reflect an Agency endorsement of this
 standard per se.  Moreover,  as discussed below,
 the Agency believes that the  activities  regulated
 under the various environmental statutes generally
 have  serious and substantial impacts on human
 health and welfare.  As  a  result, the Agency
 believes  that Tribes usually will be able to meet
 the Agency's operating  rule, and that use of such
 a  rule  by  the  Agency should  not  create an
 improper burden of proof on Tribes or create the
 administratively  undesirable  result  of checker-
boarding reservations.
 Whether a Tribe has jurisdiction over activities by
 nonmembers  will be  determined case by  case,
 based on factual findings.  The determination as
 to  whether the required effect  is present in a
 particular case depends on the circumstances.

 Nonetheless,  the Agency  may also  take  into
 account the provisions of environmental statutes,
 and any legislative findings that the effects of the
 activity are serious,  in making a  generalized
 finding that Tribes are likely to possess sufficient
 inherent   authority   to   control   reservation
 environmental quality.5   As a result, in  making
 the required factual findings as to the impact of a
 water-related activity on a particular Tribe, it may
 not  be necessary to  develop  an extensive and
 detailed record in each  case.   The Agency may
 also rely on  its special expertise  and practical
 experience  regarding  the importance  of water
 management,   recognizing   that  clean  water,
 including critical habitat (e.g., wetlands,  bottom
 sediments, spawning beds), is absolutely crucial to
 the survival of many Indian reservations.

 The Agency believes that congressional enactment
 of  the Clean  Water  Act  establishes  a strong
 Federal interest in effective management of water
 quality.   Indeed, the primary objective of the
 CWA "is to restore and maintain the chemical,
 physical, and  biological  integrity of the Nation's
 waters"  (section  101(a)), and to  achieve that
 objective,  the  Act   establishes  the  goal  of
 eliminating all discharges of pollutants into the
 navigable waters of the United States and attaining
 a level  of water quality that is  fishable and
 swimmable (sections 101(a)(l) and (2)). Thus the
 statute  itself constitutes, in effect, a legislative
 determination   that  activities  affecting  surface
 water and critical habitat quality may have serious
 and substantial impacts.

EPA also notes that, because of the mobile nature
of pollutants in surface waters  and the relatively
small length or size of stream segments or other
water bodies on reservations, it would be  very
difficult to separate  the  effects of water  quality
impairment on non-Indian fee  land  within a
reservation  as compared with  those on tribal
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portions.  In other words, any impairment that
occurs on, or as a result of, activities on non-
Indian fee lands is very likely to impair the water
and  critical habitat quality  of the tribal lands.
This also suggests that the serious and substantial
effects of water  quality impairment  within  the
non-Indian portions of a reservation are very
likely to affect the tribal interest in water quality.
EPA believes that  a  "checkerboard"  system  of
regulation, whereby the Tribe and State split up
regulation  of  surface  water   quality   on  the
reservation,  would  ignore   the difficulties  of
assuring compliance with water quality standards
when  two   different  sovereign   entities   are
establishing standards for the same small stream
segments.

EPA also believes that Congress has expressed a
preference for tribal regulation of surface water
quality to ensure compliance with CWA goals.
This  is confirmed  by  the  text and  legislative
history  of  section 518  itself.   The  CWA
establishes   a   policy   of   "recognizfing],
preserv[ing],  and   protect[ing]  the  primary
responsibilities  and rights of States to  prevent,
reduce, and eliminate pollution, [and]  to plan the
development and  use  (including  restoration,
preservation, and enhancement) of land and water
resources"   (section 101 (b)).  By  extension,  the
treatment  of Indian Tribes as States means that
Tribes are to be primarily responsible  for  the
protection of reservation  water resources.   As
Senator Burdick, floor manager of the 1987 CWA
Amendments, explained, the purpose of section
518 was to "provide clean water for the people of
this Nation"  (133 Congressional Record S1018,
daily ed., Jan.  21,  1987).  This goal was to be
accomplished, he asserted, by giving "tribes . . .
the  primary  authority  to   set  water  quality
standards to assure fishable and swimmable water
and to satisfy all beneficial uses. "6

In light of the  Agency's statutory responsibility
for implementing the environmental statutes, its
interpretations  of  the  intent  of  Congress  in
allowing for tribal management of water quality
within the reservation are entitled to substantial
deference.7
The Agency also believes that the effects on tribal
health and welfare  necessary  to  support tribal
regulation  of  non-Indian  activities  on  the
reservation may  be easier to establish  in  the
context of water quality management than with
regard to zoning, which was at issue in Brendale.
There is a significant distinction between land use
planning and  water quality management.  The
Supreme Court has explicitly recognized  such a
distinction: "Land use planning in essence chooses
particular uses  for the  land;    environmental
regulation .  .  .  does not mandate particular uses
of the land but requires only that, however the
land is used, damage to the environment  is kept
within prescribed limits."8  The Court has relied
on this distinction to support a finding that States
retain authority  to  carry  out  environmental
regulation even  in  cases  where their ability to
carry out general land use regulation is preempted
by Federal law.9

Further, water quality management  serves  the
purpose of protecting  public health and  safety,
which is  a core governmental function  whose
exercise is  critical  to self-government.    The
special status of governmental actions to  protect
public health and safety is  well established.  By
contrast, the power to zone can be exercised to
achieve purposes that  have little  or no  direct
nexus to public  health and safety.10  Moreover,
water pollution is by nature highly mobile, freely
migrating from one local jurisdiction  to another,
sometimes over  large distances.   By  contrast,
zoning regulates the uses of particular properties
with  impacts  that are much more likely to  be
contained within a given local jurisdiction.
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                                                                     Chapter 1 - General Provisions
Operationally,     EPA's   generalized  findings
regarding the  relationship of  water quality  to
tribal health and  welfare  will  affect the legal
analysis  of a  tribal  submission by, in  effect,
supplementing the factual showing a Tribe makes
in applying for authority to administer the water
quality  standards  program.     Thus,  a tribal
submission  meeting the requirements of section
131.8  of this  regulation  will  need to make a
relatively simple showing of facts that there are
waters within the reservation used by the Tribe  or
tribal members (and thus that the Tribe or tribal
members   could  be   subject  to exposure   to
pollutants present in,  or introduced into, those
waters),  and that the waters  and critical habitat
are subject  to protection under the Clean Water
Act.  The Tribe must also explicitly assert that
impairment of such waters by  the  activities  of
non-Indians would have a serious and substantial
effect on the  health and  welfare of the  Tribe.
Once the Tribe meets this initial burden, EPA
will, in light of the facts presented by the Tribe
and the generalized statutory and factual findings
regarding the  importance  of reservation water
quality discussed above, presume that there has
been an adequate showing of tribal jurisdiction on
fee lands, unless an  appropriate governmental
entity  (e.g.,   an  adjacent   Tribe   or  State)
demonstrates a lack of jurisdiction on the part  of
the Tribe.

The Agency recognizes that jurisdictional disputes
between  Tribes and States can be complex and
difficult and that it will, in some circumstances,
be forced to address  such disputes.  However,
EPA's ultimate responsibility is protection of the
environment.    In view  of  the  mobility   of
environmental problems, and the interdependence
of various jurisdictions, it  is imperative that all
affected   sovereigns   work  cooperatively  for
environmental protection rather than engage  in
confrontations over jurisdiction.

To  verify authority,  the Tribe  is  required  to
include  a statement signed by  the  tribal legal
counsel, or an equivalent official, explaining the
legal basis for the  Tribe's regulatory authority.
Tribe also  is  required to provide  appropriate
additional  documentation  (e.g.,  maps,  tribal
codes, and ordinances).

The fourth criterion requires that the Tribe, in the
Regional  Administrator's judgment,  should be
reasonably capable of administering an effective
standards  program.  The Agency recognizes that
certain Tribes have not had substantial experience
in administering surface water quality programs.
For this reason, the Agency requires that Tribes
either show  that  they  have  the   necessary
management and technical skills or submit a plan
detailing  steps  for acquiring  the   necessary
management and technical skills.  The plan must
also address how the Tribe will obtain the funds
to  acquire  the   administrative  and  technical
expertise.  When considering tribal capability, the
Agency will also consider whether the Tribe can
demonstrate  the  existence  of institutions  that
exercise   executive,  legislative,  and  judicial
functions, and whether the Tribe has a history of
successful  managerial  performance  of public
health or environmental programs.

1.8.2 Application for Authority To Administer
      the Water Quality Standards Program

The  specific  information  required  for  tribal
applications to EPA is described in 40 CFR.  The
application is required, in general, to include a
statement on tribal recognition by the Department
of  the  Interior, documentation  that  the tribal
governing body has substantial duties and powers,
documentation of tribal authority to regulate water
quality on the federally recognized reservation, a
narrative   statement  of  tribal  capability  to
administer water quality standards programs, and
any other  information requested by the Regional
Administrator.

When evaluating tribal experience in public health
and environmental programs  (under  paragraph
131.8(b)(4)(ii), EPA will look for indications that
the Tribe  has  participated  in such  programs,
whether the programs are administered by EPA,
other  Federal agencies, or Tribes.  For example,
several Tribes are known to have participated in
developing areawide water management plans or
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tribal water quality standards.  EPA will also look
for  evidence  of  historical  budget allocations
dealing  with  public  health  or  environmental
programs along with any experience in monitoring
related programs.

The  regulation allows a Tribe to describe either
how  it presently has the capability to manage an
effective water quality standards program or how
it proposes to acquire the additional administrative
and technical expertise to manage such a program.
EPA will carefully review for reasonableness any
plans that propose to acquire expertise. EPA will
not approve tribal capability demonstrations where
such plans do not include reasonable provisions
for acquisition  of needed personnel as well as
reliable  funding sources.   This requirement is
consistent  with other Clean Water Act programs.
Tribes may wish to apply for section 106 funds to
support  their water quality  standards programs
and may include this source in any discussion of
obtaining necessary funds.

If the  Tribe has qualified to  administer other
Clean Water Act  or  Safe  Drinking Water  Act
programs, then the Tribe need  only provide the
information   that   has  not   been  submitted
previously.

Qualifying for administration of the water quality
standards program is  optional for Indian Tribes
and  there  is no  time  frame limiting when such
application may  be made.  As a general policy,
EPA will  not deny a  tribal application.  Rather
than  formally deny the Tribe's request, EPA will
continue to work cooperatively with the Tribe in
a continuing effort to  resolve deficiencies  in the
application or the tribal program  so that tribal
authorization may occur. EPA also concurs with
the view that the intent of Congress and the EPA
Indian Policy is to support tribal governments in
assuming  authority to  manage  various  water
programs.  Authority  exists for EPA to re-assert
control  over certain water programs due  to the
failure  of  the  State  or Tribe  to  execute the
programs  properly.   Specifically, in the water
quality standards program, the Administrator has
authority to promulgate Federal standards.
1.8.3 Procedure Regional Administrator Will
      Apply

The review procedure established in section 131.8
is  the   same procedure  applicable to all water
programs.  Although experience with the initial
application in  other programs  indicated some
delay in the process, EPA believes that as EPA
and  the  Tribes  gain  experience  with  the
procedures, delays will be minimal.

The EPA review procedure in paragraph 131.8(c)
specifies  that   following  receipt   of  tribal
applications,  the  Regional  Administrator  will
process such applications in a  timely  manner.
The procedure calls for prompt notification to the
Tribe  that the  application  has  been received,
notification  within  30   days   to  appropriate
governmental  entities  (e.g., States  and other
governmental entities located contiguous to the
reservation and that possess authority to regulate
water quality under section 303 of the Act) of the
application and  the substance and basis for the
Tribe's assertion of authority over reservation
waters, and allowance  of 30  days  for review of
the Tribe's assertion  of authority.

EPA recognizes that city and county governments
which  may  be subject to or affected by tribal
standards  may  also  want to comment on the
Tribe's assertion of authority.   Although EPA
believes that the responsibility to coordinate with
local governments falls primarily  on the State, the
Agency will make an effort to provide notice to
local governments by placing an announcement in
appropriate newspapers.  Because the rule limits
EPA to considering comments from governmental
entities with  Clean Water Act  section  303
authority, such  newspaper announcements  will
advise interested parties  to direct  comments on
tribal authority to appropriate State governments.

Where  a  Tribe's  assertion of  authority  is
challenged,  the  Regional   Administrator,  in
consultation with  the  Tribe,  the  governmental
entity   challenging  the   Tribe's  assertion  of
authority, and the  Secretary of the Interior, will
determine  whether  the  Tribe  has  adequately
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                                                                      Chapter 1 - General Provisions
demonstrated authority to regulate water quality
on  the   reservation.    Where  the  Regional
Administrator concludes that  the Tribe has  not
adequately demonstrated its authority with respect
to an area in dispute, then tribal assumption of the
standards   program   would  be   restricted
accordingly.   If the authority in dispute  were
focused  on  a  limited  area,  this  would  not
necessarily  delay  the  Agency's  decision   to
authorize the Tribe to administer the program for
the nondisputed areas.

The procedure  allowing participation by  other
governmental entities in  EPA's review of  tribal
authority  does  not imply  that States or Federal
agencies (other than  EPA) have veto power over
tribal  applications  for treatment  as  a  State.
Rather,  the  procedure is  simply  intended  to
identify any competing jurisdictional claim and
thereby ensure that  the Tribe has the  necessary
authority  to administer the standards  program.
EPA will not rely solely  on the  assertions of a
commenter who challenges the Tribe's  authority;
EFA will make  an independent evaluation of the
tribal showing and all available information.

When  evaluating  tribal assertions of  authority,
EPA will apply  the test from Montana  v. United
States, 450 U.S. 544  (1981), and will consider the
following:

•  all  information submitted  with the  Tribe's
   assertion of authority;

•  all information submitted during the required
   30-day comment  period by the governmental
   entities identified  in 40 CFR 131.8(c)(2); and

•  all information obtained by the Agency  via
   consultation  with  the  Department  of  the
   Interior (such consultation  is required where
   the   Tribe's   assertion   of   authority   is
   challenged).

EPA and the  Department  of the  Interior  have
agreed to procedures  for conducting consultations
between the agencies. The procedure established
as the  Secretary of  the Interior's designees the
Associate Solicitor,  Division  of Indian Affairs,
and the Deputy  Assistant Secretary -  Indian
Affairs (Trust and Economic Development). EPA
will forward a copy of the application and any
documents asserting a competing or conflicting
claim of authority to such designees as soon  as
possible.   For most applications, an EPA-DOI
conference will be scheduled from 1 to 3 weeks
after the date the Associate Solicitor  receives the
application.    Comments  from the  Interior
Department  will  discuss  primarily  the  law
applicable to the issue to assist EPA in its own
deliberations. Responsibility for legal advice  to
the  EPA  Administrator or other EPA  decision
makers  will  remain  with  the EPA  General
Counsel.    EPA  does  not  believe that the
consultation process  with  the Department of the
Interior should involve notice and opportunity for
States  and   Tribes  because  such  parties are
elsewhere provided appropriate opportunities  to
participate in EPA's  review of tribal  authority.

EPA will take all reasonable  means to  advise
interested  parties   of the  decision  reached
regarding  challenges  of  tribal  assertions   of
authority.    At  least,  written  notice  will  be
provided  to  State(s)  and  other governmental
entities sent notice of  the tribal application.  In
addition, the  Water Quality Standards Regulation
requires  EPA  to publish an   annual  list  of
standards  approval  actions taken  within the
preceding year.  EPA  will expand that listing  to
include Indian Tribes qualifying for treatment as
States in the preceding year.

Comments on  tribal  compliance with  criteria
necessary for assuming the program is limited  to
the  criterion for  tribal authority.   The  Clean
Water Act does not require EPA to provide public
comment on the entire tribal application, nor does
EPA believe that public comment will assist with
EPA's  decision-   making  regarding  the  other
criteria. (The other criteria are the recognition of
the Tribe by the Department  of the Interior, a
description of the tribal governing body, and the
capability of the Tribe  to administer  an effective
standards program.)  EPA believes that providing
public  comment on  these  three criteria  would
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Water Quality Standards Handbook - Second Edition
unnecessarily complicate and potentially delay the
process.

1.8.4 Time  Frame  for  Review  of  Tribal
      Application

EPA has not specified a time frame for review of
tribal application.   The Agency believes  it is
impossible  to  approve   or  disapprove  all
applications within a designated time  frame.
Because   EPA  has  no   reasonable  way  to
predetermine how complete  initial applications
might be, what  challenges might arise, or how
numerous or complex the  issues might be, the
Agency  deems  it inappropriate  to  attempt  to
establish  time  frames  that might   not  allow
sufficient time for resolution.  Similarly, EPA's
experience with  States applying for various EPA
programs indicates that, at times, meetings and
discussions  between  EPA and  the  States are
necessary before all requirements are met.  The
Agency believes that the  same communication
with  Tribes  will  be  important  to  ensure
expeditious processing of tribal applications.
1.8.5 Effect  of
      Decision
Regional   Administrator's
A decision by the Regional Administrator that a
Tribe  does  not meet  the   requirements  for
administering the water quality standards program
does not preclude the Tribe from resubmitting the
application at a future date. Rather than formally
deny the Tribe's request, EPA will continue to
work cooperatively with the Tribe in a continuing
effort to resolve  deficiencies in the application or
the tribal program so that tribal authorization may
occur.   EPA believes that the intent of Congress
and of EPA's Indian Policy is to  support tribal
governments in  assuming authority to manage
various  water programs.

Where the Regional Administrator determines that
the  tribal  application  satisfies   all  of  the
requirements of section 131.8,  the  Regional
Administrator will promptly notify the Tribe that
the Tribe  has qualified to administer the water
quality standards program.
1.8.6 Establishing Water Quality Standards on
      Indian Lands

Where Tribes qualify to be treated as States for
the purposes of water quality standards, EPA has
the responsibility to assist the Tribe in establishing
standards that are appropriate for the reservation
and consistent with the Clean Water Act.  EPA
recognizes that  Tribes have limited resources for
development of water quality standards.

EPA  considers  the  following  three   options
acceptable to complete  the task  of establishing
water quality standards on Indian  lands:

•  the  Tribe  may  negotiate   a  cooperative
   agreement with an adjoining State to apply the
   State's standards to the Indian  lands;

•  the Tribe may incorporate the  standards from
   an adjacent State as the Tribe's own; or

•  the Tribe may independently develop and adopt
   standards that account for unique site-specific
   conditions and water body uses.

The first two options would be the quickest and
least  costly  ways for establishing  tribal water
quality standards.  Under option 1, the negotiated
agreement could also cover requirements such as
monitoring,   permitting,   certifications,   and
enforcement  of water quality standards on the
reservation.   Option 2 would make full use of
information and data developed by the State which
may  apply   to  the  reservation.    Tribes,  as
sovereign governments, have the legal authority to
negotiate cooperative agreements  with a State to
apply that  State's  standards to  waters  on the
reservation or to use State standards as the basis
for tribal standards. These options do not suggest
that the Tribe relinquishes its sovereign powers or
enforcement  authority  or that  the  State  can
unilaterally  apply its  standards  to  reservation
waters.

Option 3 would require more time and resources
to implement because it would require the Tribe
to create an  entire set  of standards  "from
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                                                                     Chapter 1 - General Provisions
scratch." EPA does not intend to discourage this
approach, but notes that Indian Tribes may want
to make full use, where appropriate, of programs
of  adjacent  States.    Tribes  should  use  this
Handbook   as   guidance   when  developing
standards.

EPA emphasizes that the development of tribal
water quality standards is an iterative process, and
that the  standards  development  option initially
selected by the Tribe can change in subsequent
years.  For example, a Tribe  may want  to use
option 1 or 2 to get the standards program started.
This does not preclude the Tribe from developing
its  own  water quality  standards  in subsequent
years.

Tribes establishing standards  for the first time
should carefully consider which water body uses
are  appropriate.     Once designated  uses  are
adopted,  removing  the  use  or adopting  a
subcategory of  use  would  be  subject  to the
requirements of  section  131.10  of the  Water
Quality Standards Regulation.

EPA expects that,  where Tribes qualify to be
treated as States for the  purposes of water quality
standards,   standards   will  be   adopted  and
submitted to EPA for review within 3 years (a
triennium) from the date that the Tribe is notified
that it is qualified to  administer the standards
program.   This  time frame corresponds  to  that
provided to States  under the provisions  of the
1965 Federal Water Pollution Control Act, when
the water quality standards program was created.
EPA  believes   that   this  is   an   equitable
arrangement, and  that the  Tribes should  be
allowed sufficient time to develop their programs
and  adopt  appropriate standards for reservation
waters.

Once EPA determines that a Tribe qualifies to
administer   the   standards   program,   tribal
development,  review, and adoption  of water
quality standards  are  subject  to  the  same
requirements that States are subject to under the
Clean  Water  Act  and  EPA's  implementing
regulations.

Until Tribes qualify for the standards program and
adopt standards under the Clean Water Act, EPA
will, when possible,  assume that existing water
quality standards  remain applicable.    EPA's
position  on  this  issue   was  expressed  in  a
September  9,  1988,  letter  from  EPA's then
General  Counsel, Lawrence  Jensen,  to Dave
Frohnmayer, Attorney General for the State of
Oregon.    This  letter  states:  "if States  have
established standards that purport to apply to
Indian reservations,  EPA  will assume  without
deciding that those standards remain applicable
until a Tribe is authorized to establish its own
standards or until EPA otherwise  determines in
consultation with a State and Tribe that the State
lacks jurisdiction .  . . ."   This policy is not an
assertion   that   State   standards   apply   on
reservations as a matter of law,  but the policy
merely recognizes that fully implementing a role
for Tribes under the Act will require a transition
period. EPA may apply  State standards in this
case because (1) there are no Federal standards
that apply generally, and (2) to ignore previously
developed State standards would be a regulatory
void that EPA believes would not be beneficial to
the reservation water quality. However, EPA will
give serious consideration to Federal promulgation
of water quality standards on Indian lands where
EPA finds a particular need.

Where a State asserts authority to establish future
water  quality standards for a reservation,  EPA
policy  is to ensure that the affected Tribe is made
aware of the assertion so that any issues the Tribe
may  wish to raise can be reviewed as part of the
normal standards  setting  process.    EPA also
encourages   State-Tribe   communication   on
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standards issues, with one possible outcome being
the  establishment  of   short-term  cooperative
working agreements pertaining to  standards and
NPDES permits on reservations.

1.8.7 EPA  Promulgation of  Standards for
      Reservations

If  EPA  determines that  a  Tribe  possesses
authority   to   regulate   water  quality   on  a
reservation  but  the Tribe  declines to  seek
authority to administer the water quality standards
program, EPA has the authority under section 303
of the Act to promulgate Federal water quality
standards.  EPA's responsibility stems from the
Act's directive to establish water quality standards
for all "navigable waters."  Depending on the
circumstances,  EPA may use the standards of an
adjacent  State  as a starting point  for  such  a
promulgation.     EPA  will  prioritize  the
promulgations based on various factors,  not the
least of which is availability of Agency resources
to undertake  the  Federal  rulemaking process.
Because the Federal promulgation process is slow
and complex, EPA may promulgate water quality
standards  in conjunction with re-issuing permits
on the reservations.

The intent of the Clean Water Act is for States
and Tribes qualifying for treatment  as States to
have the first opportunity to set standards.  Thus,
EPA  prefers  to work cooperatively with States
and Tribes on water quality standards issues and
to initiate Federal  promulgation  actions  only
where absolutely necessary.

EPA's entire policy with  respect  to Federal
promulgation  is  straightforward.    EPA much
prefers to  work with the States and have them
adopt  standards   that   comply   with   CWA
requirements.   Where Federal promulgation  is
necessary  to achieve CWA compliance, however,
EPA will act.  This same philosophy will apply to
Indian  Tribes  authorized  to  administer the
program.
 1.91   Adoption of  Standards for  Indian
^™••   Reservation Waters

This guidance recognizes that Tribes have varying
abilities to develop water quality standards. Some
Tribes  have  more  technical  capability  and
experience in drafting implementable  regulations
than other Tribes and may be capable of adopting
more complex standards.  However, most Tribes
may not have access to sufficient resources, either
in personnel or in contractor funds, to pursue this
course.    Moreover,  EPA  does  not have  the
resources  to   provide  substantial   technical
assistance to individual Tribes to  develop other
than basic water quality standards.

1.9.1 EPA's  Expectations for  Tribal  Water
      Quality Standards

Tribal water quality standards, initially at least,
should focus on basic contents and reflect existing
uses and existing  water quality.   The standards
must be established for an inventory of "waters of
the  United  States," including wetlands.   The
Tribes should focus on the basic  structure  of a
water quality standards  system:  designated uses
for  identified  water  segments,  appropriate
narrative and numeric criteria, an antidegradation
policy, and other general implementation policies.
How complex or sophisticated these elements need
to be depends upon the  abilities of the Tribe and
the  environmental concerns affected by  tribal
standards.

EPA has consistently recommended to Tribes that
they use directly, or with slight modification, the
standards of the adjacent States as a beginning for
tribal standards.   Tribal water quality standards
should be developed considering the quality and
designated  uses  of waters entering and leaving
reservations.   It  is important that  the  Tribes
recognize what the surrounding State  (or another
Indian reservation) water quality  standards are
even though there is no  requirement to match
those standards,  although the   water   quality
standards regulation does require consideration of
downstream water quality standards (see  section
2.2, this Handbook).
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                                                                      Chapter 1 - General Provisions
At a minimum, tribal water  quality standards
should be established upstream and downstream
from point  sources  where NPDES permits are
applicable.  It is also desirable  that water quality
standards be applied to waters  where significant
nonpoint sources enter so that the effectiveness of
best management  practices on the reservation's
waters can be evaluated.

Water quality criteria should be carefully selected
recognizing that making criteria more stringent in
subsequent  water quality  standards  reviews is
more  feasible  than  attempting  relaxation  of
stringent criteria.  While there is no mandatory
list of criteria, the following should be considered
the minimum:

•  narrative "free froms";

•  dissolved oxygen;

•  pH;

•  temperature;

•  bacteriological  criteria (for recreational  and
   ceremonial uses); and

•  toxics   (including  nonconventionals,  e.g.,
   ammonia and chlorine).   [Use of option 1,
   section 2.1.3, is recommended.]

1.9.2 Optional Policies

The Tribes must also specify which optional
policies they wish to  use pursuant to 40 CFR
131.13  (see chapter 6, this Handbook).  These
include the following:

•  mixing zones for point sources;

•  variances for point sources;

•  design   low-flow   specification   for   the
   application of numeric criteria;  and

•  schedules  of  compliance  for  criteria  in
   NPDES,  and permits.
Guidance for applying these policies are generally
available  in either  this  Handbook  or  in  the
Technical Support Document for Water Quality-
based Toxics Control (USEPA, 1991a).

1.9.3 Tribal Submission and EPA Review

The initial submission  of the tribal water  quality
standards must contain the items listed in 40 CFR
131.6 plus use attainability analyses for all waters
not classified "fishable/swimmable" (see  section
2.9,  this Handbook).    In addition,  it  should
contain identification of endangered or threatened
aquatic  species or wildlife subject to protection by
water quality standards.  There  should also be
included a record containing information  on the
regulatory  and public participation aspects of the
water quality standards, public comments made,
and the Tribe's responses to those comments and
other relevant  material required  by  40 CFR
131.20.

1.9.4 Regional Reviews

The  Regions should  carefully  coordinate  the
reviews within the Water Management Divisions
to ensure:

•  that  the required  items  in  section  131.6  are
   included;

•  that all waters with NPDES permits have water
   quality standards; and

•  that   the  tribal   rulemaking  meets   the
   requirements of 40 CFR 131.20.

In commenting on tribal water quality standards,
the Regions should identify situations where the
dispute  resolution mechanism in  40 CFR 131.7
may ultimately be called into play and  should
attempt to de-fuse such  situations as  early as
possible in the standards adoption process. One
possibility  is to encourage Tribes and States to
establish review procedures before any specific
problem develops as suggested in section 131.7(e)
of the regulation.
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Where NPDES  permits exist,  the  downstream
jurisdiction and the Region should determine if
total  maximum  daily  loads  or  waste   load
allocations  will be needed.  Where this burden
falls on the Tribe, EPA may need to assist the
Tribe  in  these  assessments  or  perform  the
necessary modeling for the Tribe.   The Region
also should assess the scope of any section 401
procedures   needed in  future  NPDES permit
renewals.   The interstate nature of tribal  water
quality standards may become important to EPA
because of the recent Arkansas v. Oklahoma U.S.
Supreme Court case (112 section 1046, February
26,  1992),  especially when  EPA is the permit
writing authority.
        NOTE:      Additional   discussion
        supporting the Agency's  rulemaking
        with respect  to Indian Tribes and
        EPA's views on related questions may
        be found in the preamble discussion to
        the   final   rule  (56  F.R.  64893,
        December 12,  1991).
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                                                                    Chapter 1 - General Provisions
                                        Endnotes

    1. Champion International Corp. v. EPA, 850 F.2d 182 (4th Cir.  1988)

    2. Oklahoma Tax Commission v. Citizen Band Potawatomi Indian Tribe of Oklahoma, 111 S.Ct.
      905, 910 (1991).

    3. Brendale v. Confederated Tribes and Bands of the Yakima Nation, 492 U.S. 408,  (1989)

    4. Montana v. United States,  450 U.S. at 565-66 (citations omitted).

    5. See, e.g., Keystone Bituminous CoalAssoc. v. DeBenedictis, 480 U.S. 470, 476-77 and notes
      6, 7  (1987).

    6. Id.

    1. Washington Dept. of Ecology v. EPA,  752 F.2d 1465,  1469  (9th Cir. 1985); see generally
      Chevron,  USA v. NRDC, 467 U.S. 837, 843-45 (1984).

    8. California Coastal  Commission v.  Granite Rock Co., 480 U.S.  572, 587 (1987).

    9. Id.  at 587-89.

    10. See e.g. Brendale, 492 U.S. at 420 n.5 (White, J.)  (listing broad range of consequences of
      state zoning decision).
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                                                              Chapter 2 - Designation of Uses
                                 CHAPTER 2

                          DESIGNATION OF USES

                                (40 CFR 131.10)


                               Table of Contents
2.1  Use Classification - 40 CFR 131.10(a)	2-1
     2.1.1     Public Water Supplies   	2-1
     2.1.2     Protection and Propagation of Fish, Shellfish, and Wildlife	2-1
     2.1.3     Recreation	  2-2
     2.1.4     Agriculture  and Industry   	2-3
     2.1.5     Navigation   	2-4
     2.1.6     Other Uses	 .  2-4

2.2  Consider Downstream Uses - 40 CFR 131.10(b)	2-4

2.3  Use Subcategories - 40 CFR 131.10(c)	2-5

2.4  Attainability of Uses - 40 CFR 131.10(d)	2-5

2.5  Public Hearing for Changing Uses -  40 CFR 131.10(e)	2-6

2.6  Seasonal Uses - 40 CFR 131.10(f)   	2-6

2.7  Removal of Designated Uses -  CFR 40	2-6
     2.7.1     Step  1 - Is the Use Existing?   	2-6
     2.7.2     Step 2 - Is the Use Specified in Section 101(a)(2)?    	2-8
     2.7.3     Step 3 - Is the Use Attainable?  	2-8
     2.7.4     Step 4 - Is a Factor from 131.10(g) Met?	2-8
     2.7.5     Step 5 - Provide Public Notice  	2-8

2.8  Revising Uses to Reflect Actual Attainment - 40 CFR 131.10(i)  	2-8

2.9  Use Attainability Analyses - 40 CFR 131.100) and (k)	2-9
     2.9.1     Water Body Survey and Assessment - Purpose and Application	2-9
     2.9.2     Physical Factors  	2-10
     2.9.3     Chemical Evaluations	2-12
     2.9.4     Biological Evaluations	2-12
     2.9.5     Approaches  to Conducting  the Physical, Chemical, and Biological
              Evaluations   	2-15
     2.9.6     Estuarine  Systems  	2-18
     2.9.7     Lake Systems	2-23

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                                                                     Chapter 2 - Designation of Uses
                                        CHAPTER 2
                                DESIGNATION OF USES
         Use Classification - 40 CFR 131.10(a)
A water quality standard defines the water quality
goals of  a water body or portion thereof, in part,
by designating the use or uses to be made of the
water.  States adopt water quality  standards to
protect  public health or welfare, enhance  the
quality of water, and serve the purposes of the
Clean Water  Act.   "Serve the purposes of the
Act" (as defined in sections 101(a)(2), and 303(c)
of the Act) means that water quality standards
should:

•  provide, wherever attainable, water quality for
   the  protection  and  propagation  of fish,
   shellfish, and  wildlife, and recreation in and
   on the water ("fishable/swimmable"),  and

•  consider the use and value of State waters for
   public  water supplies, propagation of fish and
   wildlife, recreation,  agriculture and industrial
   purposes, and navigation.

These sections of the Act describe  various uses of
waters that are considered desirable and should be
protected.  The States must take these uses into
consideration  when classifying State waters and
are free  to add use  classifications.  Consistent
with  the  requirements  of the  Act and Water
Quality  Standards Regulation, States are free to
develop and adopt any  use classification  system
they  see  as  appropriate,   except  that  waste
transport and assimilation is not an acceptable  use
in any case (see 40 CFR 131.10(a)). Among the
uses listed in  the Clean Water  Act, there is no
hierarchy.    EPA's  Water  Quality  Standards
Regulation emphasizes  the  uses specified   in
section 101(a)(2) of the Act (first  bullet,  above).
To be consistent with the 101(a)(2) interim goal
of the Act, States must  provide water quality for
the protection  and propagation offish, shellfish,
and wildlife, and provide for recreation in and on
the water ("fishable/swimmable") where attainable
(see 40 CFR 131.10(j)).
           DESIGNATED USES
              40 CFR 131,3(f)

       Uses specified in Water Quality
       Standards for each water body or
       segment whether or not they are
       being attained.
2.1.1 Public Water Supplies

This use includes waters that are the source for
drinking water supplies and often includes waters
for food processing.  Waters for drinking water
may require treatment prior to  distribution in
public water systems.

2.1.2 Protection and  Propagation  of  Fish,
      Shellfish, and Wildlife

This classification is often divided  into several
more specific subcategories,  including coldwater
fish, warmwater fish, and shellfish. For example,
some coastal States have a  use specifically for
oyster propagation.   The use may also include
protection  of  aquatic   flora.    Many  States
differentiate   between   self-supporting   fish
populations  and stocked  fisheries.    Wildlife
protection should include waterfowl,  shore birds,
and other water-oriented wildlife.

To more fully protect aquatic habitats and provide
more comprehensive assessments of aquatic life
use attainment/non-attainment, it is EPA's policy
that States should designate aquatic life uses that
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Water Quality Standards Handbook - Second Edition
appropriately  address biological  integrity and
adopt biological criteria necessary to protect those
uses (see Appendix R).
             TYPES OF USES
        CWA SECTION 303(e)(2)
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                                                                      Chapter 2 - Designation of Uses
   Option 3

Designate  either  primary  contact  recreation,
secondary contact recreation (with bacteriological
criteria  sufficient  to support  primary  contact
recreation), or conduct use attainability analyses
demonstrating  that recreational uses consistent
with  the CWA  section 101(a)(2) goal are not
attainable for all waters of the State.  Such use
attainability  analyses are required  by  section
131.10  of   the   Water   Quality   Standards
Regulation, which  also specifies six  factors that
may  be used  by  States in demonstrating  that
attaining a use is not feasible.   Physical factors,
which are important in determining attainability of
aquatic life uses, may not be used as the basis for
not designating a recreational use consistent with
the CWA section 101(a)(2) goal.  This precludes
States from  using  40  CFR 131.10(g) factor 2
(pertaining to low-flows) and factor 5 (pertaining
to physical factors in general).  The basis  for this
policy  is  that  the  States and EPA  have  an
obligation to do as much as possible to protect the
health of the public.  In certain instances, people
will use whatever water bodies are available for
recreation, regardless of the physical conditions.
In conducting use  attainability analyses (UAAs)
where available  data are scarce or nonexistent,
sanitary surveys are useful  in determining the
sources  of bacterial  water quality indicators.
Information  on  land  use  is  also  useful  in
predicting bacteria  levels and sources.

   Other Options

•  States  may   apply  bacteriological   criteria
   sufficient to support primary contact recreation
   with  a   rebuttable  presumption  that  the
   indicators show  the presence of human  fecal
   pollution.    Rebuttal  of  this  presumption,
   however,  must be based on a sanitary  survey
   that demonstrates a lack of contamination from
   human sources.   The basis  for this  option is
   the   absence    of  data   demonstrating   a
   relationship   between  high   densities   of
   bacteriological water quality indicators  and
   increased  risk of swimming-associated illness
   in animal-contaminated  waters.  Maine is an
   example  of a  State  that has  successfully
   implemented this option.

•  Where States adopt a  standards package that
   does not support the swimmable goal and does
   not contain a UAA to justify the omission,
   EPA  may conditionally approve  the  package
   provided that (1) the State commits, in writing,
   to a  schedule  for  rapid  completion of the
   UAAs,   generally  within  90   days   (see
   conditional approval guidance in section 6.2 of
   this Handbook); and (2) the omission may be
   considered  a minor  deficiency   (i.e.,  after
   consultation with  the  State, EPA determines
   that there is no basis  for concluding that the
   UAAs would support upgrading the use of the
   water body). Otherwise, failure to support the
   swimmable goal is a major  deficiency  and
   must be disapproved to allow prompt Federal
   promulgation action.

•  States may conduct basinwide use attainability
   analyses  if  the circumstances relating  to the
   segments in question are sufficiently similar to
   make the results  of the  basinwide  analyses
   reasonably applicable to each segment.

States may add other recreation classifications as
they see fit.   For example,  one State  protects
"consumptive   recreation"   (i.e.,    "human
consumption of aquatic life, semi-aquatic life, or
terrestrial wildlife that depend on  surface waters
for survival  and well-being").  States also may
adopt seasonal  recreational uses (see section 2.6,
this Handbook).

2.1.4 Agriculture and Industry

The agricultural use classification  defines waters
that   are  suitable  for  irrigation   of  crops,
consumption by livestock, support of vegetation
for range grazing, and other  uses in support of
farming and  ranching and protects livestock and
crops from  injury  due to irrigation and other
exposures.

The industrial use classification includes industrial
cooling   and  process  water supplies.     This
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Water Quality Standards Handbook - Second Edition
classification protects industrial equipment from
damage  from  cooling  and/or  process  waters.
Specific  criteria would depend on the industry
involved.

The Report of the  Committee on  Water Quality
Criteria, the "Green Book"  (FWPCA, 1968)  and
Water Quality  Criteria 1972,  the "Blue Book"
(NAS/NAE, 1973) provide information for certain
parameters   on   protecting  agricultural   and
industrial uses,  although section 304(a)(l) criteria
for  protecting  these  uses   have   not  been
specifically   developed   for   numerous   other
parameters,  including toxics.

Where   criteria  have   not  been   specifically
developed for agricultural and industrial uses, the
criteria developed  for human health and aquatic
life are  usually sufficiently stringent to protect
these uses.   States also  may  establish criteria
specifically designed to protect these uses.

2.1.5 Navigation

This use  classification is designed to protect ships
and their crews and to maintain water quality so
as not to restrict or prevent  navigation.

2.1.6 Other Uses

States may adopt other uses they  consider to be
necessary.   Some  examples include  coral  reef
preservation,  marinas,  groundwater  recharge,
aquifer   protection,  and  hydroelectric  power.
States  also  may  establish  criteria   specifically
designed to protect these uses.
         Consider Downstream Uses - 40 CFR
When  designating uses, States  should consider
extraterritorial  effects of their  standards.   For
example, once  States revise or  adopt  standards,
upstream jurisdictions  will be  required,  when
revising their standards and  issuing permits,  to
provide for attainment and maintenance  of the
downstream standards.
Despite the regulatory requirement  that  States
ensure  downstream  standards  are  met  when
designating  and  setting   criteria  for  waters,
occasionally downstream  standards are not  met
owing to an  upstream pollutant  source.    The
Clean Water Act  offers three  solutions to such
problems.

First, the opportunity for public participation for
new or  revised water quality standards provides
potentially   affected  parties  an   approach  to
avoiding conflicts  of water quality  standards.
States and Tribes  are encouraged to  keep other
States informed of their water  quality standards
efforts and to invite comment  on  standards for
common water bodies.

Second, permit limits under the National Pollutant
Discharge Elimination System (NPDES) program
(see section  402 of the Act) are required to be
developed  such that  applicable  water  quality
standards  are  achieved.   The  permit issuance
process  also  includes  opportunity  for  public
participation   and, thus,  provides  a   second
opportunity  to consider  and  resolve  potential
problems  regarding  extraterritorial  effects  of
water quality standards.  In a decision in Arkansas
v. Oklahoma  (112 section  1046,  February  26,
1992), the U.S.  Supreme Court  held that the
Clean Water  Act clearly  authorized  EPA to
require that point sources  in upstream States not
violate water  quality standards in downstream
States, and  that EPA's interpretation  of those
standards should govern.

Third, NPDES permits issued by EPA are  subject
to certification under the requirements of section
401 of the Act.  Section 401 requires that States
grant,  deny,  or  condition  "certification"  for
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                                                                       Chapter 2 - Designation of Uses
 federally permitted or licensed activities that may
 result in a  discharge to waters of  the  United
 States.    The  decision  to  grant  or  to deny
 certification, or to grant a conditional certification
 is based on  a State's determination regarding
 whether the proposed activity  will comply with
 applicable  water  quality  standards  and  other
 provisions.   Thus, States may  deny certification
 and prohibit EPA from issuing an NPDES permit
 that  would  violate  water  quality   standards.
 Section 401 also allows  a State to  participate in
 extraterritorial actions that will affect that State's
 waters if a federally issued permit is involved.

 In addition to the above sources for solutions,
 when the problem arises between a State and an
 Indian Tribe qualified for treatment as a State for
 water quality  standards,  the dispute resolution
 mechanism  could be invoked (see section  1.7, of
 this Handbook).
         Use Subcategories - 40 CFR 131.10(c)
States are required to designate uses considering,
at a minimum, those uses listed in section 303(c)
of  the  Clean  Water  Act  (i.e.,  public  water
supplies, propagation    of  fish  and  wildlife,
recreation,  agriculture  and industrial   purposes,
and navigation). However, flexibility inherent in
the State process for designating  uses allows the
development of subcategories of  uses within the
Act's  general  categories to refine and  clarify
specific use classes. Clarification of the use class
is particularly helpful when a variety of surface
waters with distinct characteristics  fit within the
same  use  class,  or do  not  fit  well into any
category.   Determination of non-attainment  in
waters with broad use categories may be difficult
and open  to alternative interpretations.   If a
determination of  non-attainment  is in dispute,
regulatory actions will  be difficult to accomplish
(USEPA, 1990a).

The State selects the level of specificity it desires
for identifying designated uses and  subcategories
of uses (such as whether to  treat  recreation as a
single  use  or  to  define  a  subcategory  for
 secondary recreation).  However,  the State must
 be at least as specific as the uses listed in sections
 101 (a) and 303(c) of the  Clean  Water Act.

 Subcategories of aquatic  life uses  may be on the
 basis of attainable habitat (e.g.,  coldwater versus
 warmwater  habitat);   innate  differences  in
 community structure and  function (e.g.,  high
 versus low species richness or productivity); or
 fundamental differences in  important community
 components  (e.g.,  warmwater fish communities
 dominated by bass versus catfish).  Special uses
 may  also  be designated to  protect particularly
 unique,  sensitive,  or valuable  aquatic  species,
 communities, or habitats.

 Data collected  from biosurveys  as part  of  a
 developing biocriteria program may assist  States
 in refining aquatic life use  classes by revealing
 consistent differences among aquatic communities
 inhabiting  different waters of the same designated
 use.  Measurable biological attributes could then
 be used to divide one class  into  two or more
 subcategories (USEPA, 1990a).

 If States adopt subcategories that do not require
 criteria sufficient to fully protect the goal uses in
 section 101(a)(2)  of the Act (see section 2.1,
 above), a use attainability analysis  pursuant to 40
 CFR 131.10(j) must  be conducted for waters to
 which these subcategories are assigned.  Before
 adopting  subcategories   of  uses,  States   must
 provide  notice  and  opportunity  for  a  public
 hearing because these actions are changes to the
 standards.
         Attainability   of  Uses   -  40  CFR
When  designating  uses,  States  may  wish  to
designate  only the  uses  that  are  attainable.
However, if the State does not designate the uses
specified in section 101(a)(2) of the Act, the State
must perform a use attainability  analysis  under
section  131.10(j)  of the  regulation.  States are
encouraged to  designate uses  that  the  State
believes can be attained in the future.
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"Attainable uses" are, at a minimum,  the uses
(based  on the  State's  system  of  water  use
classification)  that  can  be achieved 1) when
effluent limits under sections 301(b)(l)(A) and (B)
and section 306 of the Act are imposed on point
source dischargers and 2) when cost-effective and
reasonable best management practices are imposed
on nonpoint source dischargers.
         Public Hearing for Changing Uses - 40
         CFR 131.10(e)
The Water Quality Standards Regulation requires
States to provide opportunity for public  hearing
before adding or removing a use or establishing
subcategories of a use.  As mentioned in section
2.2   above,   the   State    should  consider
extraterritorial effects of such changes.
         Seasonal Uses - 40 CFR 131.10(f)
In some areas of the country, uses are practical
only  for  limited  seasons.    EPA  recognizes
seasonal uses in  the Water  Quality  Standards
Regulation. States may specify the seasonal uses
and criteria protective of that use as well as the
time frame for the "... season,  so long as the
criteria do  not prevent the attainment of any more
restrictive uses attainable in other seasons."

For  example,  in many northern areas,  body
contact recreation is possible only a few months
out of the year.   Several  States have  adopted
primary  contact  recreational   uses,  and   the
associated microbiological criteria, for only those
months when primary contact recreation actually
occurs,   and  have  relied  on  less  stringent
secondary contact recreation criteria to protect for
incidental  exposure  in  the   "non-swimming"
season.

Seasonal uses that may require  more stringent
criteria are uses that protect sensitive organisms
or life stages during a specific season such as the
early life stages of fish  and/or fish  migration
(e.g., EPA's Ambient Water Quality Criteria for
Dissolved Oxygen (see Appendix I) recommends
more stringent dissolved oxygen criteria for the
early life stages of both coldwater and warmwater
fish).
                                                         Removal of Designated Uses -  CFR 40
                                                         131.10(g) and (h)
Figure 2-1 shows how and when designated uses
may be removed.

2.7.1 Step 1 - Is the Use Existing?

Once a use has  been designated for a particular
water body or segment, the water body or water
body  segment  cannot  be  reclassified  for  a
different use except under specific conditions. If
a designated use is an existing use (as defined in
40  CFR 131.3)  for a particular water body, the
existing  use cannot be  removed  unless a  use
requiring more  stringent criteria is  added (see
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                                                   Chapter 2 - Designation of Uses
      Stepl
      Step 2 /|8 Use
              Specified in
      StepS
      Step 4
      StepS
                                                  May Not
                                                Remove Use
                 Is Use
               Attainable
  May Not
Remove Use
                 Any    x No
             131.10(g) factor
                 met?
  May Not
Remove Use
              Public Notice
May Remove
 Figure 2-1.   Process for Removing a Designated Use
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section 4.4, this Handbook, for further discussion
of existing uses).  However, uses requiring more
stringent criteria may always be added because
doing so reflects the goal of further improvement
of water quality.   Thus, a recreational use for
wading  may be deleted if a recreational use for
swimming  is added, or the State  may add the
swimming use and keep the wading use as well.

2.7.2 Step 2 - Is the Use Specified in Section
If the State wishes to remove a designated use
specified in section 101 (a) (2) of the Act, the State
must  perform  a use attainability  analysis (see
section 131.10(j)).  Section 2.9 of this Handbook
discusses use attainability analyses for aquatic life
uses.

2.7.3 Step 3 - Is the Use Attainable?

A State may change activities within a specific use
category but may not change to a use that requires
less  stringent  criteria,  unless  the State  can
demonstrate  that the designated use cannot  be
attained.   (See section  2.4,  above,  for the
definition of "attainable uses.")  For example, if
a  State  has a broad  aquatic  life use,   EPA
generally  assumes that the  use will support  all
aquatic life.  The State may demonstrate that, for
a  specific  water  body,  such  parameters  as
dissolved oxygen or temperature will not support
trout   but   will   support   perch   when
technology-based effluent limitations are applied
to   point    source   dischargers   and   when
cost-effective and reasonable best  management
practices are applied to nonpoint sources.
(1)   naturally occurring pollutant concentrations
      prevent the attainment of the use;

(2)   natural,  ephemeral,  intermittent,  or low-
      flow conditions or water levels prevent the
      attainment   of  the  use,  unless  these
      conditions may be compensated  for by the
      discharge of sufficient volume of effluent
      discharges  without violating  State  water
      conservation requirements to enable uses to
      be met;

(3)   human-caused  conditions  or  sources of
      pollution prevent the attainment  of the use
      and cannot  be remedied  or would  cause
      more environmental damage to correct than
      to leave in place;

(4)   dams,  diversions,   or  other  types  of
      hydrologic   modifications  preclude  the
      attainment of the use, and it is not feasible
      to  restore the water body  to its  original
      condition or to operate such modification in
      a way that would result in  the attainment of
      the use;

(5)   physical conditions related  to the natural
      features of the water body, such as the lack
      of a proper  substrate, cover, flow, depth,
      pools, riffles, and  the  like, unrelated to
      [chemical]    water   quality,    preclude
      attainment of aquatic life protection uses; or

(6)   controls more stringent than those required
      by sections 301(b)(l)(A) and (B) and 306 of
      the  Act would  result in  substantial  and
      widespread economic and  social  impact.
2.7.4 Step 4 - Is a Factor from 131.10(g) Met?   2.7.5 Step 5 - Provide Public Notice
Even  after  the  previous  steps  have  been
considered, the designated use may be removed,
or subcategories of a use established, only under
the conditions given  in section  131.10(g).  The
State must be able to demonstrate that attaining
the designated use is not feasible because:
As provided for in section 131.10(e), States must
provide notice and opportunity for public hearing
in accordance with section 131.20(b) (discussed in
section 6.1 of this Handbook).  Of course, EPA
intends for States to make appropriate use of all
public comments received through such notice.
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                                                                      Chapter 2 - Designation of Uses
         Revising   Uses   to   Reflect   Actual
         Attainment - 40 CFR 131.10(i)
When performing its triennial review, the State
must evaluate what uses are being attained.  If a
water body is designated for a use  that requires
less stringent criteria than. a  use that  is being
attained, the State must revise the use on that
water body to  reflect  the  use  that is  being
attained.
         Use  Attainability Analyses - 40  CFR
         131.100) and (k)
Under  section  131.10(j) of the  Water Quality
Standards  Regulation,  States   are  required to
conduct a  use  attainability   analysis  (UAA)
whenever:

(1)   the State designates or has designated uses
      that  do not include the uses specified in
      section 101(a)(2) of the Act; or

(2)   the State wishes to remove a designated use
      that  is specified in section 101(a)(2) of the
      Act or adopt subcategories of uses specified
      in  section  101(a)(2)  that require  less
      stringent criteria.

States  are  not required to conduct UAAs when
designating uses that  include those specified in
section 101(a)(2) of the Act, although  they may
conduct  these  or   similar   analyses   when
determining  the  appropriate  subcategories  of
section 101(a)(2) goal  uses.
States may also conduct generic use attainability
analyses  for  groups  of water  body  segments
provided  that the circumstances relating  to  the
segments  in  question  are  sufficiently similar to
make  the  results  of  the   generic   analyses
reasonably applicable to each  segment.

As  defined  in  the  Water  Quality  Standards
Regulation (40  CFR  131.3),  a  use attainability
analysis is:

   ... a structured scientific  assessment of
   the factors affecting the attainment of a  use
   which  may  include physical,   chemical,
   biological,   and    economic  factors   as
   described  in  section 131.10(g).

The  evaluations  conducted  in  a  UAA  will
determine the attainable uses for a water body
(see sections  2.4 and 2.8, above).

The physical,  chemical,  and biological factors
affecting the attainment of a use are evaluated
through a water body survey and assessment.  The
guidance on  water body  survey and assessment
techniques that  appears in this  Handbook is  for
the evaluation of fish, aquatic life, and wildlife
uses only (EPA has not developed guidance for
assessing recreational uses). Water body surveys
and assessments conducted by the States should be
sufficiently  detailed  to answer  the  following
questions:

•  What are  the aquatic use(s)  currently  being
   achieved in the water body?

•  What are the causes of any impairment of the
   aquatic uses?

•  What are the aquatic use(s)  that can be attained
   based on the physical, chemical, and biological
   characteristics of  the water body?

The  analysis  of  economic  factors  determines
whether substantial and widespread economic and
social  impact  would  be  caused  by  pollution
control requirements more stringent than (1) those
required under sections 301(b)(l)(A) and (B) and
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section   306  of  the  Act  for  point  source
dischargers, and (2) cost-effective and reasonable
best management  practices for nonpoint source
dischargers.

2.9.1 Water Body  Survey  and  Assessment -
      Purpose and Application

The purpose of  this section is  to  identify the
physical,  chemical,  and  biological  factors  that
may be examined to determine whether an aquatic
life protection use is attainable for a given water
body.   The specific analyses included in  this
guidance are optional.  However, they represent
the type of analyses EPA believes are sufficient
for States to justify changes in uses designated in
a water  quality  standard  and to determine uses
that are  attainable.   States may use  alternative
analyses as long  as  they are scientifically  and
technically   supportable.      This   guidance
specifically addresses streams and river systems.
More detailed guidance is given in the Technical
Support   Manual:   Waterbody   Surveys   and
Assessments  for  Conducting  Use  Attainability
Analyses, Volume I (USEPA, 1983c).  EPA has
also developed guidance for estuarine and marine
systems  and  lakes,  which  is  summarized in
following sections.  More detailed guidance for
these aquatic systems is available in the Technical
Support Manual,  Volume II, Estuarine Systems,
and Volume III, Lake Systems (USEPA, 1984a,b).

Several approaches for analyzing the aquatic life
protection uses  to determine  if  such uses are
appropriate for a given water body are discussed.
States  are encouraged to use  existing data to
perform the physical,  chemical,  and biological
evaluations presented in this  guidance document.
Not all  of these evaluations are  necessarily
applicable.  For example,  if an assessment reveals
that the physical habitat is the limiting  factor
precluding a use, a chemical evaluation would not
be  required.   In addition,  wherever possible,
States  also should  consider grouping together
water bodies having  similar physical,  chemical,
and biological   characteristics  either  to  treat
several water bodies or  stream  segments as a
single unit or to establish representative conditions
applicable to other similar water bodies or stream
segments within a river basin.   Using  existing
data and  establishing representative conditions
applicable  to  a  number  of water bodies  or
segments should conserve the limited resources
available to the States.

Table  2-1   summarizes  the  types of physical,
chemical,  and biological  factors  that  may  be
evaluated when conducting  a UAA.   Several
approaches  can  be  used  for  conducting  the
physical, chemical,  and  biological evaluations,
depending  on the complexity of  the situation.
Details on the  various evaluations can be  found in
the  Technical Support  Manual:    Waterbody
Surveys  and  Assessments for Conducting  Use
Attainability Analyses, Volume I (USEPA, 1983c).
A survey need not consider all of the parameters
listed;  rather,  the  survey should  be designed on
the basis of the water body  characteristics  and
other  considerations  relevant  to  a particular
survey.

These  approaches may be adapted  to the water
body  being  examined.    Therefore,   a close
working relationship between EPA and the States
is essential so  that  EPA can assist States in
determining the appropriate analyses to be used in
support of any water quality standards revisions.
These  analyses should  be made  available to all
interested parties before any public forums on the
water quality standards to allow for full discussion
of the  data and analyses.

2.9.2    Physical Factors

Section 101(a) of the Clean Water Act recognizes
the importance of preserving the physical integrity
of the Nation's water bodies. Physical habitat
plays  an  important  role in  the overall aquatic
ecosystem  and impacts the types and number of
species present  in a particular body of  water.
Physical parameters of a water body are examined
to identify factors that impair the propagation and
protection  of  aquatic life and to determine what
uses could  be obtained in the water body given
such limitations.  In general, physical parameters
such as flow,  temperature, water depth,  velocity,
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                                                                        Chapter 2 - Designation of Uses
        PHYSICAL FACTORS

        4 instream
         characteristics
        - size (mean
          width/depth)
        - Sow/velocity  .
        - annual hydrology
        - total volume
        - reaeratkm rates
        - gradient/pools/
          riffles
        -temperature
        - sedimentation
        -channel
          modifications
        * channel
        *• substrate
         composition and
         characteristics

        • channel debris

        • stedge deposits

        • riparian
         characteristics

        • downstream
         characteristics
CHEMICAL FACTOKS

•  dissolved oxygen

•  toxicants

•  suspended solids

•  nutrients
 - nitrogen
 - phosphorus

•  sediment oxygen
  demand

•  salinity
• alkalinity

• pH

• dissolved: solids
BIOLOGICAL FACTORS

• biological
  inventory
  (existing use
  analysis)
-fish
- maerojavertebrates
- microinvertebrates
- phytoplankton
- periphytofi
- macrophytes

• biological
  potential
  analysis
- diversify indices
- HSI models
- tissue analyses
• recovery index
- intolerant species analysis
- omnivore-caraivore
  analysis

• biological
  potential
                                   reference  reach
                                   comparison
  Table 2-1.  Summary of Typical Factors Used in Conducting a  Water Body Survey and
              Assessment
substrate, reaeration rates, and other factors are
used to identify any physical limitations that may
preclude  attainment   of  the  designated  use.
Depending on the water body in question, any of
the physical parameters listed in Table 2-1 may be
appropriately examined.  A State may use any of
these parameters to identify physical limitations
and characteristics  of a water body.  Once a State
has identified any  physical limitations based  on
evaluating   the   parameters   listed,   careful
consideration of "reversibility" or the ability to
restore the physical integrity of the water body
should be made.
           Such considerations may include whether it would
           cause more environmental damage to correct the
           problem than to leave the water  body as is, or
           whether physical impediments such as dams can
           be  operated or modified in  a  way that would
           allow attainment of the use.

           Several   assessment   techniques   have   been
           developed   that   correlate  physical   habitat
           characteristics   to  fishery   resources.     The
           identification of physical factors limiting a fishery
           is a critical assessment that provides important
           data for management of  the  water body.   The
           U.S. Fish  and Wildlife Service  has developed
           habitat  evaluation procedures  (HEP) and habitat
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suitability indices (HSI).   Several  States have
begun   developing   their  own   models  and
procedures for habitat assessments.   Parameters
generally   included   in   habitat   assessment
procedures are temperature, turbidity,  velocity,
depth,  cover,  pool  and  riffle  sizes,   riparian
vegetation, bank  stability, and siltation.  These
parameters are correlated  to fish  species by
evaluating the habitat variables important to the
life cycle of the species.  The value of habitat for
other  groups  of aquatic  organisms  such  as
macroinvertebrates and periphyton also may be
considered. Continued research and refinement of
habitat   evaluation   procedures   reflect   the
importance of physical habitat.

If physical limitations of a stream restrict the use,
a variety of habitat modification techniques might
restore a  habitat  so that  a species could thrive
where  it  could   not before.    Some of  the
techniques that   have  been  used  are  bank
stabilization,   flow control,  current  deflectors,
check dams, artificial meanders, isolated oxbows,
snag  clearing when  determined  not  to  be
detrimental to the life cycle or reproduction of a
species, and  installation of spawning  beds and
artificial  spawning channels.  If  the  habitat is  a
limiting factor to the propagation and/or survival
of aquatic life, the feasibility of modifications
might be examined before additional controls are
imposed on dischargers.

2.9.3 Chemical Evaluations

The chemical characteristics of a water body are
examined to  determine why a designated use is
not being met and to  determine the potential of a
particular species to survive in the water body  if
the concentration of particular  chemicals were
modified.    The  State  has  the discretion  to
determine the parameters  required to perform an
adequate water chemistry evaluation.   A partial
list of the parameters that  may  be evaluated is
provided in Table 2-1.

As part of the evaluation of the water chemistry
composition,  a natural background evaluation is
useful  in determining the relative contribution of
natural  background  contaminants to  the  water
body;  this  may  be  a legitimate  factor that
effectively prevents a designated  use from being
met.     To  determine  whether  the  natural
background   concentration  of  a  pollutant  is
adversely impacting  the survival  of species, the
concentration may be compared to one of the
following:

•  304(a) criteria guidance documents; or

•  site-specific criteria; or

•  State-derived  criteria.

Another way to  obtain  an  indication  of the
potential for the  species to survive is to determine
if the species are found in other  waterways with
similar chemical concentrations.

In determining whether human-caused pollution is
irreversible, consideration needs to be given to the
permanence of  the  damage,  the  feasibility  of
abating   the   pollution,    or   the   additional
environmental  damage that  may  result  from
removing the pollutants.  Once a State identifies
the chemical or  water quality  characteristics that
are limiting attainment of the use, differing levels
of remedial control  measures may be explored.
In  addition, if  instream  toxicants  cannot  be
removed by natural processes  and  cannot  be
removed  by   human  effort  without   severe
long-term environmental  impacts,  the pollution
may be  considered irreversible.

In some areas, the water's chemical characteristics
may have to be  calculated using predictive water
quality models.  This will be true if the receiving
water is to  be  impacted  by  new  dischargers,
changes  in  land  use, or  improved  treatment
facilities. Guidance is available  on the selection
and use  of receiving water models for biochemical
oxygen  demand, dissolved oxygen,  and ammonia
for  instream  systems  (USEPA,  1983d,e) and
dissolved oxygen, nitrogen, and  phosphorus for
lake  systems,   reservoirs,  and  impoundments
(USEPA, 1983f).
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                                                                      Chapter 2 - Designation of Uses
2.9.4 Biological Evaluations

In evaluating what aquatic life protection uses are
attainable,  the biology of the water body should
be evaluated.  The interrelationships between the
physical, chemical, and biological characteristics
are  complex,  and  alterations  in  the  physical
and/or chemical parameters result in biological
changes.  The biological evaluation described in
this section encourages States to:

•  provide a more  precise  statement of  which
   species  exist in the water body and should be
   protected;

•  determine the biological  health of the water
   body; and

•  determine the  species that could potentially
   exist  in the  water body  if the physical and
   chemical  factors  impairing  a  use   were
   corrected.

This  section of the guidance will present the
conceptual   framework   for   making   these
evaluations.  States  have  the discretion to use
other scientifically  and  technically  supportable
assessment methodologies deemed appropriate for
specific  water  bodies on  a case-by-case  basis.
Further details  on each of the analyses presented
can be found in the Technical Support Manual for
Conducting Use Attainability Analyses (USEPA,
1983c).

   Biological Inventory (Existing Use Analysis)

The  identification of which  species are in the
water body and should be protected serves several
purposes:
                                       M
•  By  knowing what  species  are present,  the
   biologist can analyze, in general terms,  the
   health of the water body.  For example, if the
   fish species present are principally carnivores,
   the  quality of the water  is generally higher
   than in a water body dominated by omnivores.
   It also  allows  the  biologist  to  assess  the
   presence or absence of intolerant species.

•  Identification of the species enables the State to
   develop baseline conditions against  which to
   evaluate  any   remedial    actions.   The
   development of a regional baseline based upon
   several  site-specific species  lists increases an
   understanding  of the regional  fauna.   This
   allows for easier grouping of water bodies
   based on the biological regime of the area.

•  By identifying the species, the decision-maker
   has  the data needed  to  explain the present
   condition of the  water body to the public and
   the  uses that must be  maintained.

The evaluation of the existing biota may  be simple
or complex depending  on data  availability.  As
much information as possible should be gathered
on the  categories of organisms listed in Table 2-1.
It is not necessary to obtain complete data  for all
six categories.  However, it is recommended that
fish should be included in  any  combination of
categories chosen because:

•  the   general public  can  relate  better  to
   statements  about the condition of the  fish
   community;

•  fish are typically present even in the smallest
   streams  and in  all  but  the  most  polluted
   waters;

•  fish are relatively easy to identify, and samples
   can  be sorted and identified  at the field  site;

•  life-history information is extensive  for many
   fish  species  so  that stress  effects can  be
   evaluated (Karr,  1981).  In addition,  since fish
   are  mobile,  States are encouraged to evaluate
   other categories of organisms.
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Water Quality Standards Handbook - Second Edition
Before any field work is conducted, existing data
should be collected. EPA can provide data from
intensive monitoring surveys and special studies.
Data, especially for fish, may be available from
State fish  and  game  departments,  recreation
agencies,  and local governments,  or  through
environmental impact statements, permit reviews,
surveys, and university or other studies.

   Biological   Condition/Biological  Health
   Assessment

The biological inventory can  be used  to gain
insight into the biological health of the water body
by evaluating:

•  species richness or the number of species;
•  presence of intolerant species;
•  proportion of omnivores  and  carnivores;
•  biomass or production; and
•  number of individuals per species.

The role  of  the  biologist  becomes critical  in
evaluating  the health  of the biota  because the
knowledge  of expected  richness  or  expected
species  comes  only  from understanding  the
general  biological traits and regimes of the area.
Best professional judgments by local biologists are
important.   These judgments are based on many
years of experience and  on observations of the
physical and chemical changes that have occurred
over time.

Many methods for evaluating biotic communities
have been  and continue to  be developed.  The
Technical Support Manual for  Conducting Use
Attainability Analyses (USEPA, 1983c) and Rapid
Reassessment Protocols for Use in Streams and
Rivers (USEPA,   1989e)  describe methods that
States  may  want  to consider  using  in their
biological evaluations.

A number of other methods have been  and are
being  developed   to  evaluate   the  health  of
biological components of the aqfejatic ecosystem
including   short-term   in  situ $or  laboratory
bioassays  and partial or  full list-cycle  toxicity
tests.  These methods  are  disddbsed in several
EPA   publications,  including  the  Biological
Methods Manual (USEPA,  1972).   Again, it is
not the intent of this document to specify tests to
be conducted by the States.  This will depend on
the information available, the predictive accuracy
required,  site-specific  conditions  of the  water
body  being  examined, and  the  cooperation  and
assistance the State receives  from  the  affected
municipalities and industries.

   Biological Potential Analysis

A significant step in the use attainability analysis
is the evaluation of  what communities  could
potentially exist  in  a  particular water  body if
pollution were  abated  or if the physical habitat
were  modified.   The  approach presented is to
compare the water body in question to reference
reaches within a region.  This approach includes
the development of baseline conditions to facilitate
the comparison  of  several water bodies at  less
cost.   As with  the other  analyses mentioned
previously,  available  data  should  be  used to
minimize resource impacts.

The biological potential analysis involves:

•  defining boundaries of fish faunal regions;

•  selecting  control  sampling  sites in  the
   reference reaches of each area;

•  sampling fish and recording observations at
   each reference sampling site;

•  establishing  the community characteristics
   for the reference reaches  of each area; and

•  comparing the water body in question to the
   reference reaches.

In establishing  faunal regions  and sites, it is
important to select reference areas for  sampling
sites that have conditions typical of the region.

The establishment  of  reference areas  may be
based on physical and hydrological characteristics.
The number of reference reaches needed will be
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                                                                       Chapter 2 - Designation of Uses
determined  by  the  State  depending  on  the
variability of the waterways within the State and
the number of classes that the State may wish to
establish.  For example, the State may  want to
use  size,  flow, and  substrate  as the defining
characteristics and  may  consequently desire  to
establish  classes  such  as   small, fast  running
streams with sandy substrate or large,  slow rivers
with  cobble bottom.  It is  at the option of the
State to:

•  choose the parameters to be used in classifying
   and establishing reference reaches; and

•  determine the number of classes (and  thus the
   refinement) within  the faunal  region.

This approach can also be applied to other aquatic
organisms such as macroinvertebrates (particularly
freshwater mussels) and algae.

Selection of the reference  reaches is of critical
importance because the characteristics  of  the
aquatic  community will  be  used to establish
baseline conditions against which similar reaches
(based   on    physical   and    hydrological
characteristics) are compared. Once the reference
reaches  are  established,  the  water body  in
question can be compared to the  reference reach.
The results of this analysis will reveal whether the
water body in question has  the typical biota for
that class or a less desirable community and will
provide  an  indication  of  what  species  may
potentially exist if pollution were abated or the
physical habitat limitations were  remedied.

2.9.5 Approaches to  Conducting the Physical,
      Chemical, and  Biological Evaluations

In some cases, States that assess the status of their
aquatic resources,   will  have  relatively simple
situations not requiring extensive data collection
and evaluation.  In other situations, however, the
complexity resulting from variable environmental
conditions and the stress from multiple uses of the
resource will require both intensive and extensive
studies  to produce a sound  evaluation  of the
system.   Thus, procedures that  a   State may
develop for conducting a water body assessment
should be flexible enough  to be adaptable  to a
variety of site-specific conditions.

A  common  experimental  approach   used  in
biological assessments has  been a  hierarchical
approach  to the analyses.  This can  be  a rigidly
tiered approach.   An  alternative is presented in
Figure 2-2.

The flow chart  is a general  illustration  of a
thought process used to conduct a use attainability
analysis.     The  process  illustrates   several
alternative  approaches  that  can  be  pursued
separately or, to varying degrees, simultaneously
depending on:

•  the amount of data available on the site;

•  the  degree  of  accuracy  and  precision
   required;

•  the importance of the resource;

•  the site-specific conditions  of the  study
   area; and

•  the controversy associated with the site.

The degree of sophistication is variable for each
approach.  Emphasis  is  placed  on  evaluating
available data first.  If information is found to be
lacking  or incomplete, then  field testing or field
surveys should be conducted.

The major elements of the process are briefly
described below.

   Steps 1 and 2

Steps 1 and 2 are the basic organizing steps in the
evaluation process.   By carefully  defining  the
objectives and scope of the evaluation, there will
be some indication of the level of sophistication
required in subsequent surveys and testing. States
and the regulated community can then adequately
plan and allocate resources to the analyses.  The
designated use of the water body  in  question
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                     Stepl
                                Define objectives
                                Determine designated we
                                Determine physical, chemical, and biological
                                minimum requlrementi for use
                                Establish data needs
                                Gather existing data
                     Step 2
                     StepS
                                         Analyze existing data
                                                     Data Inadequate
                                                                                 Data adequate • proceed to Step 6
                                  Based on following criteria chocs* one
                                  approach (Step 5) for conducting
                                  evaluation:
                                                   Available data
                                                   Accuracy and precision needed
                                                   Importance of resource
                                                   Site-specific conditions
                                                   Time and money available
                     Step 4

                     StepS
                                      Select reference water bodies
        fit
                                  Approaches for Additional Evaluations
 A-  Conduct general survey.
   -  Physical habitat survey, I appropriate
   -  Chemical survey, H appropriate
     Biological survey, V appropriate

     Evaluate physical habitat and water quality alterations
   -  Identify lype, source, area of Impact
   -  Examine physfcsi chemical, biological variables
   -  Conduct short-term/hstt/or lab btoassay tests If toxics suspected
r
 C-  EvsJuateletnporal and/or spatial changes In physical, chemical, blotoglcsl variables
   -  Increase frequency and number of samples to quantify variables
   -  Conduct chemical survey to characterize dtefrlbutlorVseurae of compourtds If chronic taxtolty suspected
   -  Conduct biological and chemical surveillance if toxicity varies
   -  Conduct tissue analysis If Moconeer*alion suspected
i
 D-  Refine estimates of physical, chemical, biological effects
   -  Analyze habitat requirements and tolerance limits for representative and important species
   -  Conduct partial or full life cyde chronic tests, behavioral and Uectarical asea^ prootadortfeeplratlon estimate*
                     Step 6
                                        - Integrate information
                                        - Summarize conclusions
                                        - Determine if additional information is needed
                     Step?
                                    Make recommendations concerning water body potential,
                                        desired level of attainability, and us* designation
  Figure 2-2. Steps in a Use Attainability Analysis
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                                                                      Chapter 2 - Designation of Uses
 should  be  identified  as  well as  the  minimum
 chemical,  physical, and  biological requirements
 for maintaining the use.  Minimum requirements
 may  include,  for example,  dissolved  oxygen
 levels, flow rates, temperature, and other factors.
 All relevant information on the water body should
 be  collected  to  determine  if  the  available
 information is  adequate  for  conducting  an
 appropriate level of analysis.  It is assumed that
 all water body evaluations, based on existing data,
 will either  formally or informally be conducted
 through Steps 1 and 2.

   Steps 3  and 4

 If the available  information  proves inadequate,
 then   decisions   regarding   the   degree   of
 sophistication required in the  evaluation  process
 will need to be made.  These decisions will, most
 likely, be based on the five criteria listed in Step
 3  of Figure  2-2.   Based on these decisions,
 reference areas should be chosen  (Step  4),  and
 one or more of the testing approaches should be
 followed.

   Steps 5A, B, C, D

 These approaches are  presented  to  illustrate
 several  possible ways of  analyzing  the water
 body.  For example, in some cases chemical data
 may be readily available for  a  water body but
 little or no  biological  information  is known.  In
 this case, extensive chemical sampling may not be
 required, but enough samples should be taken to
 confirm the accuracy  of the  available data  set.
 Thus, to accurately define the biological condition
 of the resource, 5C may  be chosen, but 5A may
 be pursued  in a less intensive way  to supplement
 the chemical data already available.

 Step 5A is a general survey to establish relatively
coarse ranges for physical and chemical variables,
and the numbers and relative abundances of the
biological   components   (fishes,   invertebrates,
primary producers) in the water body.  Reference
areas may or may not  need to be evaluated here,
depending on the types of questions being asked
and the degree of accuracy required.
Step 5B focuses more narrowly on  site-specific
problem areas with the intent of separating, where
possible, biological  impacts  due   to  physical
habitat  alteration  versus  those due  to chemical
impacts.   These categories  are  not mutually
exclusive but some attempt should  be made  to
define the causal factors in a stressed area so that
appropriate control measures can be implemented
if necessary.

Step 5C would be conducted to evaluate possibly
important trends in the spatial and/or temporal
changes associated with the physical, chemical,
and biological variables of interest.  In general,
more rigorous quantification of these variables
would be needed to allow for more sophisticated
statistical analyses between reference and study
areas which would, in turn, increase the degree of
accuracy and confidence in the predictions based
on this  evaluation. Additional laboratory testing
may  be included,  such  as  tissue  analyses,
behavioral  tests,  algal assays, or tests for flesh
tainting. Also, high-level chemical analyses may
be needed,  particularly if the presence  of toxic
compounds is suspected.

Step 5D is, in some respects, the most detailed
level of study.  Emphasis  is placed  on refining
cause-effect  relationships   between  physical-
chemical alterations and the biological responses
previously established from available data or steps
5A through 5C.   In many cases, state-of-the-art
techniques  will be used.  This pathway would be
conducted  by the States only  where it may be
necessary to establish, with a  high degree  of
confidence, the cause-effect relationships that are
producing   the   biological   community
characteristics   of   those   areas.       Habitat
requirements or tolerance limits for representative
or important species may have to be determined
for those factors  limiting  the potential  of the
ecosystem.   For these evaluations, partial or full
life-cycle toxicity tests, algal assays, and sediment
bioassays may be needed  along with the  shorter
term bioassays  designed  to elucidate  sublethal
effects  not  readily apparent  in toxicity  tests
(e.g.,    preference-avoidance   responses,
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production-respiration   estimates,   and
bioconcentration estimates).

   Steps 6 and 7

After field sampling is completed, all data  must
be integrated and summarized. If this information
is still not adequate, then further testing may be
required and a more  detailed pathway chosen.
With adequate data, States should be able to make
reasonably specific recommendations concerning
the natural potential of the water body, levels of
attainability consistent  with this  potential,  and
appropriate use designations.

The evaluation procedure outlined here allows
States   a  significant   degree  of  latitude  for
designing assessments to meet their specific goals
in water quality and water use.

2.9.6 Estuarine Systems

This section provides an overview of the factors
that should be  considered  in developing  use
attainability  analyses   for  estuaries.   Anyone
planning to conduct a use attainability analysis for
an estuary should  consult the Technical Support
Manual: Waterbody Surveys and Assessments for
Conducting Use Attainability Analyses, Volume II:
Estuarine  Systems (USEPA,  1984a)  for more
detailed guidance.  Also, much of the information
for streams and rivers that is presented above and
in Volume I of the Technical Support  Manual,
particularly with respect to chemical evaluations,
will apply to estuaries  and is not repeated here.

The term "estuaries" is generally  used to denote
the lower reaches  of a river where tide and river
flows  interact.    Estuaries  are   very   complex
receiving  waters  that are  highly variable in
description and  are not absolutes in definition,
size,  shape, aquatic  life,  or other  attributes.
Physical, chemical, and biological attributes may
require consideration unique to estuaries and are
discussed below.
   Physical Processes

Estuarine  flows  are  the result  of  a complex
interaction of the following physical factors:

•  tides;
•  wind shear;
•  freshwater inflow (momentum and buoyancy);
•  topographic factional resistance;
•  Coriolis effect;
•  vertical mixing; and
•  horizontal mixing.

In performing a use attainability  study, one may
simplify the  complex  prototype   system   by
determining which of these effects or combination
of effects is most important at the time scale of
the evaluation (days, months, seasons, etc.).

Other ways to simplify the approach to analyzing
an estuary is to  place it in a broad classification
system to permit comparison of similar types of
estuaries. The most common groupings are based
on  geomorphology,   stratification,  circulation
patterns, and  time  scales.    Each  of these
groupings is discussed below.

Geomorphological classifications can include types
such  as drowned  river  valleys  (coastal plain
estuaries),  fjords, bar-built  estuaries, and other
estuaries  that  do  not  fit  the   first  three
classifications   (those   produced  by  tectonic
activity,   faulting,   landslides,   or  volcanic
eruptions).

Stratification is  most often  used for classifying
estuaries influenced  by  tides  and  freshwater
inflows.   Generally, highly stratified estuaries
have  large river discharges  flowing into them,
partially mixed  estuaries have medium river
discharges;  and vertically  homogeneous  have
small river discharges.

Circulation  in  an   estuary  (i.e.,   the  velocity
patterns as they change over time) is primarily
affected  by  the freshwater outflow,  the tidal
inflow,  and  the effect of wind.   In  turn,  the
difference in density between outflow and inflow
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                                                                      Chapter 2 - Designation of Uses
 sets up secondary currents that ultimately affect
 the salinity distribution across the estuary.  The
 salinity distribution is important because it affects
 the  distribution  of  fauna and  flora within  the
 estuary.   It is also important  because  it  is
 indicative of the mixing properties of the estuary
 as  they may affect the dispersion of  pollutants
 (flushing properties). Additional factors such as
 friction forces and the size and geometry of the
 estuary also contribute to the circulation patterns.
 The   complex  geometry   of  estuaries,  in
 combination with the presence of wind, the effect
 of the Earth's rotation  (Coriolis effect), and other
 effects, often results in residual currents (i.e., of
 longer period than the tidal cycle) that strongly
 influence the mixing processes in estuaries.

 Consideration  of time  scales  of the  physical
 processes being  evaluated is  very important for
 any water quality study.

 Short-term conditions are much more influenced
 by  a variety of short-term events that perhaps
 have to be analyzed  to evaluate a "worst case"
 scenario.  Longer term (seasonal) conditions are
 influenced  predominantly  by  events  that are
 averaged over the duration of that time scale.

   Estuary Substrate Composition

 Characterization  of sediment/substrate properties
 is important in a use attainability analysis because
 such properties:

 •  determine the extent to which toxic compounds
   in sediments are available to the biota; and
•  determine what types of plants  and animals
   could potentially become established, assuming
   no  interference from other factors such as
   nutrient, dissolved oxygen (DO), and/or toxics
   problems.

The bottom of most  estuaries  is a mix of sand,
silt, and mud  that  has been transported  and
deposited by  ocean  currents  or  by  freshwater
sources.   Rocky areas  may  also  be present,
particularly in  the fjord-type estuary.   None of
these substrate types  is particularly hospitable to
aquatic plants and animals, which accounts in part
for the paucity of species seen  in an estuary.

The amount of material transported to the estuary
will be determined by the types of terrain through
which  the  river passes, and upon  land  use
practices that may encourage runoff and erosion.
It is important to take land use practices  into
consideration when examining the attainable uses
of the estuary. Deposition of particles varies with
location in the  estuaries and velocity of the
currents.

It is often difficult for plants to colonize estuaries
because of a lack of suitable anchorage points and
because of the  turbidity  of the water, which
restricts light   penetration  (McLusky,  1971).
Submerged   aquatic  vegetation    (SAV)
(macrophytes) develops in sheltered  areas where
silt and mud accumulate.  These plants help to
slow the currents, leading to further deposition of
silt.  The growth of plants often keeps pace with
rising  sediment levels so that over a long period
of time substantial deposits of sediment and plant
material may be seen.

SAV serves very important roles as habitat and as
a  food source  for  much of  the biota of the
estuary. Major estuary studies have shown  that
the  health  of SAV  communities serves as  an
important indicator of estuary health.

   Adjacent Wetlands

Tidal and  freshwater wetlands adjacent to  the
estuary can serve as a buffer to protect the estuary
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from external phenomena.  This function may be
particularly important during wet weather periods
when relatively high stream flows discharge high
loads of sediment and pollutants to the estuary.
The wetlands slow  the  peak velocity, to some
extent alleviate  the  sudden shock  of salinity
changes, and filter  some  of the  sediments  and
nutrients that  would  otherwise be discharged
directly into the estuary.

   Hydrology and Hydraulics

The two most important sources of freshwater to
the estuary are  stream  flow and  precipitation.
Stream  flow generally  represents  the greatest
contribution to the estuary.  The location of the
salinity gradient in a river-controlled estuary is to
a large extent a function of stream flow. Location
of  the  iso-concentration   lines   may change
considerably,  depending upon  whether  stream
flow is high or low.  This in turn may  affect the
biology of the  estuary, resulting in population
shifts as biological species adjust to changes in
salinity.  Most  estuarine species are adapted to
survive  temporary changes in salinity  either by
migration  or  some  other  mechanism   (e.g.,
mussels can close their shells).  However, many
cannot  withstand  these  changes  indefinitely.
Response of an estuary to rainfall events depends
upon  the intensity of rainfall, the drainage area
affected  by  the rainfall,  and  the  size  of the
estuary.  Movement of the salt front is dependent
upon  tidal influences and freshwater flow to the
estuary.  Variations in salinity  generally follow
seasonal patterns such  that the salt  front will
occur farther down-estuary during a rainy season
than during a dry season.   The salinity  profile
also may vary from day  to day, reflecting the
effect of individual  rainfall events,  and  may
undergo   major  changes  due  to  extreme
meteorological  events.

Anthropogenic activity also may have a significant
effect on salinity in  an estuary.   When feeder
streams are used as sources of public water supply
and the withdrawals are not  returned, freshwater
flow to the estuary is reduced, and the salt wedge
is found farther up the estuary.  If the water is
returned,  usually  in  the  form  of  wastewater
effluent, the salinity gradient of the estuary may
not  be  affected,   although  other   problems
attributable to nutrients and other pollutants in  the
wastewater may occur.

Salinity also may be  affected by  the way  that
dams along the river are operated.  Flood control
dams result in controlled discharges to the estuary
rather than relatively short but massive discharge
during  high-flow periods.   Dams operated  to
impound water for water supplies during low-flow
periods  may  drastically  alter the  pattern   of
freshwater flow to the estuary, and although  the
annual discharge may remain the same, seasonal
changes  may  have significant impact  on   the
estuary and its biota.

   Influence of Physical Characteristics on  Use
   Attainability

"Segmentation" of an estuary can provide a useful
framework  for  evaluating   the   influence   of
estuarine   physical   characteristics    such    as
circulation, mixing, salinity, and geomorphology
on   use  attainability.     Segmentation  is   the
compartmentalization of an estuary into subunits
with homogeneous physical characteristics. In  the
absence   of   water   pollution,    physical
characteristics of different regions of the estuary
tend to govern  the suitability for major water
uses.  Once the segment network is established,
each  segment   can  be  subjected  to  a   use
attainability  analysis.      In   addition,    the
segmentation process offers a useful management
structure for monitoring conformance with water
quality goals in future years.

The segmentation process is  an  evaluation tool
that recognizes that an  estuary is  an interrelated
ecosystem composed of chemically, physically,
and biologically diverse areas.  It assumes that an
ecosystem as  diverse  as  an  estuary  cannot  be
effectively managed as only one unit because
different uses and associated water quality goals
will be  appropriate and  feasible for  different
regions of the estuary.  However, after developing
a network based upon physical characteristics,
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                                                                      Chapter 2 - Designation of Uses
sediment boundaries can be refined with available
chemical  and  biological  data to maximize the
homogeneity of each segment.

A  potential   source   of  concern   about  the
construction  and  utility  of  the  segmentation
scheme for use attainability evaluations is that the
estuary is a fluid system with only a few obvious
boundaries,  such as  the sea surface and the
sediment-water interface.   Fixed  boundaries may
seem unnatural to scientists, managers, and users,
who  are  more  likely to  view the estuary  as a
continuum  than  as  a  system  composed  of
separable parts.   The best approach to dealing
with such concerns is a segmentation scheme that
stresses the dynamic nature of the estuary.  The
scheme  should  emphasize  that the  segment
boundaries are operationally defined constructs to
assist  in   understanding   a   changeable,
intercommunicating   system   of   channels,
embayments, and tributaries.

To account for the dynamic nature of the estuary,
it  is  recommended that estuarine  circulation
patterns be a prominent factor in delineating the
segment network. Circulation patterns control the
transport of and residence times for heat, salinity,
phytoplankton,  nutrients,  sediment, and  other
pollutants throughout the estuary. Salinity should
be  another important factor  in  delineating the
segment network.    The  variations  in salinity
concentrations  from  head of tide to the mouth
typically  produce  a  separation  of  biological
communities based  on  salinity  tolerances  or
preferences.

   Chemical Parameters

The most critical chemical water quality indicators
for aquatic use attainment  in an  estuary  are
dissolved oxygen, nutrients and chlorophyll-a, and
toxicants.  Dissolved oxygen (DO) is an important
water quality indicator for all fisheries  uses.  In
evaluating  use  attainability, assessments of DO
impacts should  consider the relative contributions
of three different sources of oxygen demand:
•  photosynthesis/respiration   demand   from
   phytoplankton;

•  water column demand; and

•  benthic oxygen demand.

If use impairment is occurring, assessments of the
significance of each oxygen sink can be used to
evaluate the feasibility  of achieving  sufficient
pollution control to attain the designated use.

Chlorophyll-a is the most popular indicator of
algal concentrations and nutrient overenrichment,
which  in turn  can  be  related to  diurnal  DO
depressions due to algal respiration. Typically, the
control of  phosphorus  levels  can  limit algal
growth near the head of the estuary, while the
control of nitrogen levels can limit algal growth
near the mouth of the estuary; however, these
relationships are dependent upon factors such as
nitrogen phosphorus  ("N/P")  ratios  and light
penetration potential, which can vary from  one
estuary to the next.  Excessive  phytoplankton
concentrations,  as  indicated   by  chlorophyll-a
levels, can cause adverse DO impacts such as:

•  wide diurnal  variations in surface DO due to
   daytime photosynthetic oxygen production  and
   nighttime oxygen  depletion by respiration;  and

•  depletion   of  bottom  DO   through   the
   decomposition of dead algae.

Excessive chlorophyll-a  levels  also  result  in
shading,  which  reduces  light penetration  for
submerged    aquatic   vegetation   (SAV).
Consequently, the prevention  of  nutrient over-
enrichment is probably the most important water
quality   requirement   for   a   healthy   SAV
community.

The  nutrients of greatest  concern  in the estuary
are  nitrogen and phosphorus.   Their sources
typically are discharges  from  sewage treatment
plants and industries and runoff from urban  and
agricultural areas. Increased nutrient levels lead
to phytoplankton blooms  and  a  subsequent
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reduction  in DO levels and light penetration, as
discussed  above.

Sewage treatment plants are typically the major
source of nutrients, particularly phosphorus, to
estuaries in urban areas.  Agricultural land uses
and urban land uses represent significant nonpoint
sources of nutrients, particularly nitrogen.  It is
important  to  base control  strategies   on  an
understanding of the  sources  of each  type of
nutrient, both in  the  estuary and in its feeder
streams.

Point sources of nutrients are typically much more
amenable   to  control   than nonpoint  sources.
Because  phosphorus   removal  for  municipal
wastewater discharges  is typically less expensive
than nitrogen  removal operations, the control of
phosphorus discharges is  often the method of
choice  for  the  prevention or  reversal  of use
impairment in the upper estuary (i.e., tidal fresh
zone).  However, nutrient control in the upper
reaches of the estuary  may cause algal blooms in
the lower  reaches, e.g., control  of phosphorus in
the upper reaches may reduce the algal  blooms
there, but in doing so also increase the amount of
nitrogen transported to the lower reaches where
nitrogen is the limiting nutrient  causing a bloom
there. Tradeoffs between nutrient controls for the
upper and lower estuary should  be considered in
evaluating measures for prevention  of reversing
use impairment.

Potential interferences from toxic substances, such
as  pesticides,   herbicides,  heavy  metals,  and
chlorinated effluents, also  need  to be considered
in a use  attainability  study.   The  presence of
certain  toxicants in  excessive  concentrations
within bottom sediments of the water column may
prevent the attainment  of water uses (particularly
fisheries propagation/harvesting and  sea grass
habitat uses) in estuary segments that satisfy water
quality  criteria  for DO,  chlorophyll-a/nutrient
enrichment, and fecal coliform.
   Biological Community Characteristics

The   Technical  Support Manual,   Volume   11
(USEPA,  1984a) provides  a discussion  of the
organisms typically  found in estuaries in more
detail than  is  appropriate  for  this  Handbook.
Therefore,  this  discussion  will focus  on more
general characteristics of estuarine biota and their
adaptations   to   accommodate   a   fluctuating
environment.

Salinity,   light  penetration,   and   substrate
composition are the most critical factors to the
distribution  and  survival of plant  and  animal
communities in  an  estuary.    The  estuarine
environment is  characterized  by variations  in
circulation,  salinity, temperature,  and dissolved
oxygen  supply.   Colonizing plants  and animals
must  be  able  to  withstand  the  fluctuating
conditions in estuaries.

The depth to which  attached plants may become
established is limited by turbidity  because plants
require  light for photosynthesis.  Estuaries are
typically turbid  because of large quantities  of
detritus  and  silt  contributed  by  surrounding
marshes and rivers. Algal growth also may hinder
light penetration. If too much light  is withheld
from  the lower depths,  animals  cannot rely
heavily  on  visual   cues  for habitat selection,
feeding, or finding a mate.

Estuarine organisms are recruited from the sea,
freshwater  environments,  and  the  land.   The
major environmental factors to which organisms
must  adjust  are   periodic  submersion   and
desiccation  as  well   as   fluctuating  salinity,
temperature, and dissolved oxygen.

Several  generalizations  concerning the responses
of estuarine  organisms to salinity have been noted
(Vernberg,  1983) and reflect a correlation of an
organism's habitat to its tolerance:

•  organisms living in estuaries subjected to wide
   salinity  fluctuations  can withstand a  wider
   range of salinities than species that occur  in
   high-salinity estuaries;
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                                                                       Chapter 2 - Designation of Uses
 •  intertidal zone animals tend to tolerate wider
    ranges of salinities  than  do  subtidal  and
    open-ocean organisms;

 •  low intertidal species are less tolerant of low
    salinities than are high intertidal species; and

 •  more  sessile  animals are likely  to  be more
    tolerant of fluctuating salinities than organisms
    that  are  highly  mobile  and  capable  of
    migrating during times of salinity stress.

 Estuaries  are generally  characterized  by  low
 diversity of species but high productivity because
 they serve as the nursery or breeding grounds for
 some species.  Methods to measure the biological
 health and diversity of estuaries are  discussed in
 USEPA (1984a).

    Techniques for Use Attainability Evaluations

 In assessing  use levels for aquatic life protection,
 determination of the present  use and whether this
 corresponds  to the designated use is evaluated in
 terms  of biological  measurements and indices.
 However,  if the present use  does not correspond
 to  the  designated use,  physical  and chemical
 factors  are used to explain the lack of attainment
 and the highest level the system can achieve.

 The physical  and  chemical  evaluations  may
 proceed on several levels depending  on the level
 of detail required, amount of knowledge available
 about  the system (and  similar  systems), and
 budget  for the use attainability study. As a first
 step, the estuary is classified in terms of physical
 processes  so  that  it  can  be  compared  with
 reference  estuaries  in  terms  of differences  in
 water quality and biological  communities, which
 can  be related  to  man-made alteration  (i.e.,
 pollution discharges).

 The second step is to perform desktop or simple
 computer   model  calculations  to  improve  the
 understanding  of spatial and  temporal  water
quality conditions in  the  present system.   These
calculations include continuous  point source and
 simple  box  model-type calculations.   A  more
 detailed discussion of the desktop and computer
 calculations is given in USEPA (1984a).

 The third step is  to  perform detailed analyses
 through the use of more sophisticated computer
 models.  These tools can be used to evaluate the
 system's response  to  removing  individual point
 and nonpoint source discharges, so as to assist
 with assessments  of  the cause(s)  of any  use
 impairment.

 2.9.7 Lake Systems

 This section will focus on the factors that should
 be considered  in  performing  use  attainability
 analyses for lake systems.  Lake systems are in
 most cases linked physically to rivers and streams
 and exhibit a  transition from riverine habitat and
 conditions to lacustrine habitat  and conditions.
 Therefore, the information presented in section
 2.9.1 through 2.9.5 and the Technical Support
 Manual, Volume I  (USEPA, 1983c) will to some
 extent apply to lake systems.  EPA has provided
 guidance specific to lake systems in the Technical
 Support Manual for Conducting Use Attainability
 Analyses,  Volume  III: Lake Systems  (USEPA,
 1984b).  This manual should be consulted  by
 anyone performing a use attainability analysis for
 lake systems.

 Aquatic life  uses  of a  lake  are  defined  in
 reference to the plant  and animal life in a lake.
 However, the types and abundance of the biota
 are  largely  determined  by  the  physical  and
 chemical  characteristics  of  the lake.    Other
 contributing   factors   include   the  location,
 climatological conditions,  and historical events
 affecting the lake.

   Physical Parameters

 The physical  parameters that describe the size,
 shape,  and flow regime of a lake represent the
 basic characteristics that affect physical, chemical,
 and  biological processes.    As  part of a  use
 attainability analysis, the physical parameters must
be  examined  to understand  non-water  quality
factors that affect the lake's aquatic life.
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The origins of a lake determine its morphologic
characteristics and strongly influence the physical,
chemical,  and biological conditions  that  will
prevail. Therefore, grouping lakes formed by the
same  process often will allow  comparison of
similar  lake  systems.    Measurement  of  the
following morphological characteristics may be of
importance to a water body survey:

•  surface area;
•  volume;
•  inflow and outflow;
•  mean depth;
•  maximum depth;
•  length;
•  length of shoreline;
•  depth-area relationships;
•  depth-volume relationships; and
•  bathymetry (submerged contours).

These physical parameters can in some cases be
used  to predict  biological  parameters.    For
example,  mean depth  has  been  used  as an
indicator of productivity. Shallow lakes tend to
be more productive, and  deep, steep-sided lakes
tend to be less productive. These parameters may
also be used to calculate other characteristics of
the lake such as mass flow  rate of a chemical,
surface loading rate, and detention time.

Total lake  volume and inflow and  outflow  rates
are physical characteristics that indirectly affect
the lake's aquatic community. Large inflows and
outflows for lakes  with  small volumes  produce
low detention times or high  flow-through rates.
Aquatic  life  under  these  conditions  may be
different than when relatively small inflows and
outflows occur for  a large-volume lake where
long detention times occur.

The shape  factor  (lake  length  divided  by  lake
width) also may  be correlated  to  chemical and
biological characteristics.  This factor has  been
used to predict parameters such as chlorophyll-a
levels in lakes. For more detailed  lake analysis,
information   describing  the   depth-area   and
depth-volume  relationships  and   information
describing  the bathymetry may be required.
In addition to  the  physical  parameters  listed
above, it is also important to obtain and analyze
information concerning the lake's  contributing
watershed. Two major parameters of concern are
the drainage area of the contributing watershed
and the land uses  of that watershed.  Drainage
area will aid in the analysis of inflow volumes to
the lake due to surface runoff.   The land  use
classification of the area around the lake can be
used to predict  flows  and also nonpoint source
pollutant loadings to the lake.

The physical parameters discussed above may be
used  to  understand  and  analyze  the  various
physical processes  that occur in lakes.  They can
also be used directly  in simplistic relationships
that predict productivity  to aid  in aquatic  use
attainability analyses.

   Physical Processes

Many complex and interrelated physical processes
occur  in  lakes.   These processes are highly
dependent on  the  lake's  physical parameters,
location,  and characteristics of the contributing
watershed.  Several of the major processes are
discussed below.

   Lake Currents

Water movement in a lake affects productivity and
the biota because it influences the distribution of
nutrients, microorganisms, and plankton.  Lake
currents are propagated by wind,  inflow/outflow,
and the Coriolis force.  For small shallow  lakes,
particularly long and narrow lakes, inflow/outflow
characteristics  are  most  important,   and  the
predominant current is a steady-state flow through
the lake.  For very  large lakes,  wind  is the
primary generator  of currents,  and except for
local  effects,  inflow/outflow  have a  relatively
minor effect on lake circulation.  Coriolis effect,
a  deflecting  force that is  the  function of the
Earth's rotation, also plays a role in circulation in
large lakes such as the Great Lakes.
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                                                                      Chapter 2 - Designation of Uses
   Heat Budget

Temperature and its distribution within lakes and
reservoirs affects not only the water quality within
the lake but also the thermal regime and quality of
a  river  system downstream of  the  lake.   The
thermal regime of a lake is a function of the heat
balance around the body of water. Heat transfer
modes  into  and out  of the lake include  heat
transfer  through   the  air-water    interface,
conduction through the mud-water interface, and
inflow and outflow heat advection.

Heat transfer through the air-water  interface is
primarily   responsible    for   typical    annual
temperature cycles.  Heat is transferred across the
air-water interface by three different processes:
radiation exchange, evaporation,  and  conduction.
The heat flux of  the  air-water interface is a
function  of   location  (latitude/longitude  and
elevation),    season,    time   of   day,   and
meteorological   conditions   (cloud    cover,
dew-point, temperature,  barometric pressure, and
wind).

   Light Penetration

Transmission  of  light  through  the water column
influences  primary productivity  (phytoplankton
and  macrophytes), distribution  of organisms, and
behavior of fish.  The reduction  of light through
the  water  column  of a lake  is a  function of
scattering and absorption. Light transmission is
affected by  the water surface film, floatable and
suspended    particulates,   turbidity,    dense
populations  of algae and bacteria, and color.

An important parameter based on the transmission
of light is  the depth  to which photosynthetic
activity is possible.  The minimum light intensity
required for photosynthesis has been established
to be about 1.0  percent of  the incident surface
light (Cole,  1979).  The  portion of the lake from
the surface to the depth  at which the  1.0 percent
intensity occurs is  referred  to as the  "euphoric
zone."
   Lake Stratification

Lakes in temperate and northern latitudes typically
exhibit vertical density stratification during certain
seasons  of the  year. Stratification  in  lakes  is
primarily due to temperature differences, although
salinity and suspended solids concentrations may
also affect  density.  Typically, three zones  of
thermal stratification  are formed.

The upper layer of warmer, lower density  water
is  termed  the  "epilimnion,"  and  the lower,
stagnant layer of colder,  higher density water is
termed  the  "hypolimnion."  The transition zone
between the  epilimnion  and  the  hypolimnion,
referred to as the "metalimnion," is characterized
by the maximum rate of temperature decline with
depth (the thermocline). During stratification, the
presence of the thermocline suppresses  many  of
the mass transport phenomena that are otherwise
responsible for  the vertical transport of  water
quality  constituents within  a lake.  The aquatic
community present in a lake is highly dependent
on the thermal structure.

With respect to internal flow structure,  three
distinct classes of lakes are defined:

•  strongly stratified, deep lakes characterized by
   horizontal isotherms;

•  weakly   stratified  lakes   characterized  by
   isotherms that are tilted along the longitudinal
   axis  of the reservoir; and

•  non-stratified,   completely   mixed    lakes
   characterized by isotherms that are essentially
   vertical.

Retardation  of mass  transport   between the
hypolimnion and the epilimnion results in sharply
differentiated water quality and biology  between
the lake  strata.   One of the most important
differences between the layers is often dissolved
oxygen.  As this is depleted from the hypolimnion
without being replenished, life  functions of  many
organisms  are impaired,   and the biology and
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biologically mediated  reactions  fundamental to
water quality are altered.

Vertical stratification of a lake  with respect to
nutrients can also occur.  Dissolved nutrients are
converted  to paniculate organic material through
photosynthetic  processes  in  the eptiimnion in
ecologically advanced  lakes.   This assimilation
lowers the ambient nutrient concentrations in the
epilimnion.  When the algae  die and sink to the
bottom, nutrients are carried  to the hypolimnion
where they are released by decomposition.

Temperature also has a direct effect on biology of
a lake because most biological processes (e.g.,
growth,  respiration,  reproduction,  migration,
mortality,  and decay) are strongly influenced by
ambient temperature.

   Annual   Circulation  Pattern   and  Lake
   Classification

Lakes  can be  classified  on  the basis  of their
pattern of annual mixing.  These classifications
are described below.

(1)   Amictic - Lakes that never circulate and are
      permanently covered with ice, primarily in
      the Antarctic and very high mountains.

(2)   Holomictic - Lakes that mix from top to
      bottom   as   a  result   of  wind-driven
      circulation.    Several  subcategories  are
      defined:

      • Oligomictic -  Lakes characterized by
        circulation that is unusual, irregular, and
        short  in  duration;  generally small to
        medium  tropical lakes  or very  deep
        lakes.

      • Monomictic -  Lakes that undergo one
        regular circulation per year.

      • Dimictic  - Lakes that circulate  twice a
        year, in spring and fall, one of the most
        common types of annual mixing in cool
        temperate regions such as  central and
        eastern North America.

      • Polymictic   -   Lakes  that  circulate
        frequently  or continuously, cold  lakes
        that are continually near  or slightly
        above  4°C,  or  warm equatorial  lakes
        where  air  temperature  changes  very
        little.

(3)   Meromictic -  Lakes that do not circulate
      throughout the entire water column.   The
      lower water stratum is perennially stagnant.

   Lake Sedimentation

Deposition  of   sediment  received   from   the
surrounding watershed is an  important physical
process in lakes.   Because  of the low  water
velocities through the lake or reservoir, sediments
transported by inflowing waters tend to settle out.

Sediment   accumulation  rates   are   strongly
dependent   both   on   the   physiographic
characteristics of a  specific  watershed and on
various characteristics of the lake.  Prediction of
sedimentation rates can be estimated in  two basic
ways:

•  periodic sediment surveys on a lake; and
•  estimation of watershed erosion and  bed load.

Accumulation of sediment in  lakes can,  over
many years, reduce  the life of the water body by
reducing the water  storage capacity.  Sediment
flow into the lake also reduces light  penetration,
eliminates bottom habitat for many plants and
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                                                                      Chapter 2 - Designation of Uses
 animals, and carries with it adsorbed chemicals
 and organic matter  that settle to the bottom and
 can be harmful to the ecology of the lake. Where
 sediment accumulation is a major problem, proper
 watershed   management  including  erosion  and
 sediment control must be put into effect.

    Chemical Characteristics

 Freshwater chemistry is discussed in section 2.9.3
 and in the  Technical Support Manual,  Volume I
 (USEPA, 1983c). Therefore, the discussion here
 will focus  on chemical phenomena that are of
 particular importance to lakes.  Nutrient cycling
 and  eutrophication are the primary factors of
 concern  in  this discussion, but the effects of pH,
 dissolved oxygen,  and  redox  potential  on lake
 processes are also involved.

 Water chemistry in a lake is closely related to the
 stages in  the annual lake  turnover.   Once  a
 thermocline has formed,  the  dissolved oxygen
 levels in the hypolimnion tend  to decline.  This
 occurs because the hypolimnion is isolated from
 surface waters by the thermocline and there is no
 mechanism  for aeration.

 The decay of organic matter and the respiration of
 fish and other organisms in the hypolimnion serve
 to deplete  DO.   Extreme depletion of DO may
 occur  in ice- and snow-covered lakes in which
 light  is  insufficient  for photosynthesis.    If
 depletion of DO is great enough, fish kills may
 result.   With the  depletion of DO,  reducing
 conditions prevail and many compounds that have
 accumulated in the sediment  by precipitation are
 released  to  the  surrounding  water.  Chemicals
 solubilized   under   such  conditions   include
 compounds   of  nitrogen,   phosphorus,  iron,
 manganese,  and  calcium.    Phosphorus  and
 nitrogen are of particular concern because of their
 role in the eutrophication process in lakes.

 Nutrients released  from the bottom  sediments
 during stratified  conditions are not available to
phytoplankton in the epilimnion. However, during
overturn  periods, mixing of the layers distributes
the nutrients throughout  the water column.  The
 high nutrient availability is short-lived because the
 soluble reduced  forms are  rapidly oxidized to
 insoluble forms that precipitate out and settle to
 the bottom.   Phosphorus and nitrogen  are  also
 deposited through sorption to particles that settle
 to the bottom and as dead plant material that is
 added to the sediments.

 Of the many raw materials  required by aquatic
 plants  (phytoplankton  and   macrophytes)  for
 growth, carbon, nitrogen, and phosphorus are the
 most important. Carbon is available from carbon
 dioxide, which is  in  almost unlimited supply.
 Since growth is generally  limited by the essential
 nutrient that is in lowest supply, either nitrogen or
 phosphorus is  usually  the limiting nutrient for
 growth of primary producers.  If these nutrients
 are available in adequate supply,  massive algal
 and  macrophyte blooms may occur with severe
 consequences for  the  lake.  Most  commonly in
 lakes, phosphorus  is  the limiting nutrient  for
 aquatic  plant  growth.    In  these  situations,
 adequate control of phosphorus, particularly from
 anthropogenic  sources, can  control  growth of
 aquatic vegetation.   Phosphorus  can  in  some
 cases, be  removed from  the water  column by
 precipitation,  as  described   in  the  Technical
 Support Manual,  Volume III  (USEPA, 1984b).

   Eutrophication and Nutrient Cycling

 The term  "eutrophication" is  used in two general
 ways: (1) eutrophication is defined  as the process
 of nutrient enrichment in  a water body; and (2)
 eutrophication is  used  to  describe  the effects of
 nutrient  enrichment,  that is,  the uncontrolled
 growth of plants, particularly phytoplankton,  in a
 lake   or  reservoir.     The   second  use  also
 encompasses changes in the composition of animal
 communities in the water body.   Both uses  are
 commonly  found  in  the literature,  and   the
 distinction, if important, must be discerned from
 the context of use.

 Eutrophication  is  often greatly  accelerated  by
anthropogenic nutrient  enrichment,  which   has
been termed "cultural eutrophication."  Nutrients
are transported to lakes from external  sources,
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and once in the lake, may be recycled internally.
A consideration of attainable uses in a lake must
include an  understanding  of  the  sources  of
nitrogen and phosphorus,  the  significance  of
internal cycling, especially of phosphorus, and the
changes that might be anticipated if eutrophication
could be controlled.

   Significance of Chemical Phenomena to Use
   Attainability

The  most  critical water quality indicators for
aquatic use attainment in a lake are DO, nutrients,
chlorophyll-a, and toxicants.  In evaluating use
attainability,  the  relative  importance  of  three
forms  of oxygen demand should be  considered:
respiratory   demand   of   phytoplankton  and
macrophytes during  non-photosynthetic  periods,
water column demand, and benthic demand. If use
impairment  is occurring,  assessments  of the
significance of each oxygen sink can be useful in
evaluating  the feasibility of achieving sufficient
pollution control, or  in implementing  the best
internal nutrient management practices to attain a
designated  use.

Chlorophyll-a is  a  good indicator of   algal
concentrations and of nutrient  overenrichment.
Excessive   phytoplankton  concentrations,   as
indicated by  high chlorophyll-a levels, can cause
adverse DO impacts  such as:

•  wide diurnal  variation in surface  DO due to
   daytime  photosynthesis   and   nighttime
   respiration, and

•  depletion   of  bottom  DO   through  the
   decomposition of dead algae.

As discussed previously, nitrogen and phosphorus
are the nutrients of concern in most lake systems,
particularly where anthropogenic sources  result in
increased nutrient loading.  It is important to base
control strategies on an understanding of the
sources of each type of nutrient, both in  the lake
and in its feeder streams.
Also, the presence of toxics such as pesticides,
herbicides, and heavy metals in sediments or the
water column should by considered in evaluating
uses.  These pollutants may prevent the attainment
of  uses  (particularly  those  related   to   fish
propagation and maintenance in water bodies) that
would otherwise be supported by the water quality
criteria for DO and other parameters.

   Biological Characteristics

A  major  concern  for  lake biology is  the
eutrophication due to  anthropogenic sources of
nutrients.  The increased  presence  of nutrients
may result in  phytoplankton blooms that can, in
turn, have adverse impacts on other components
of the biological community. A general trend that
results from  eutrophication is  an  increase in
numbers of organisms but a decrease in diversity
of species, particularly among nonmotile species.
The  biological  characteristics   of  lakes  are
discussed in more detail in  the Technical Support
Manual,  Volume III.

   Techniques for Use Attainability Evaluations

Techniques  for use attainability evaluations of
lakes  are discussed in detail in  the Technical
Support Manual,  Volume III.  Several empirical
(desktop)  and   simulation   (computer-based
mathematical)  models  that  can  be  used  to
characterize   and  evaluate   lakes   for   use
attainability are presented  in that document and
will not be included here owing to the complexity
of the subject.
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                                                          Chapter 3 - Water Quality Criteria
                                CHAPTERS

                      WATER QUALITY CRITERIA

                               (40 CFR 131.11)


                              Table of Contents
3.1  EPA Section 304(a) Guidance  	3-1
     3.1.1    State Use of EPA Criteria Documents	3-1
     3.1.2    Criteria for Aquatic Life Protection	3-2
     3.1.3    Criteria for Human Health Protection  	3-3

3.2  Relationship of Section 304(a) Criteria to State Designated Uses  	  3-10
     3.2.1    Recreation	3-10
     3.2.2    Aquatic Life and Wildlife	3-11
     3.2.3    Agricultural and Industrial Uses	3-11
     3.2.4    Public Water Supply	3-11

3.3  State Criteria Requirements	3-12

3.4  Criteria for Toxicants  	3-13
     3.4.1    Priority Toxic Pollutant Criteria	3-13
     3.4.2    Criteria for Nonconventional Pollutants	3-23

3.5  Forms of Criteria	3-23
     3.5.1    Numeric Criteria	3-24
     3.5.2    Narrative Criteria  	3-24
     3.5.3    Biological Criteria	3-26
     3.5.4    Sediment Criteria	3-28
     3.5.5    Wildlife Criteria  	3-31
     3.5.6    Numeric Criteria for Wetlands	3-33

Endnotes  	3-34

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                                                                  Chapter 3 - Water Quality Criteria
                                       CHAPTER 3
                            WATER QUALITY CRITERIA
The term "water quality criteria" has two different
definitions under  the Clean Water Act (CWA).
Under section 304(a),  EPA  publishes water
quality   criteria   that   consist  of  scientific
information regarding concentrations of specific
chemicals or  levels of parameters in water that
protect aquatic life and human health (see section
3.1 of this Handbook).  The States may use these
contents  as the basis for developing enforceable
water quality standards. Water quality criteria are
also  elements of State  water quality standards
adopted under  section 303 (c) of the CWA (see
sections  3.2  through 3.5  of  this  Handbook).
States are required to adopt water quality criteria
that will  protect the designated  use(s) of a water
body.  These criteria must be based on sound
scientific rationale and  must  contain sufficient
parameters  or   constituents   to  protect   the
designated use.
         EPA Section 304(a) Guidance
EPA and a predecessor  agency have produced a
series of scientific water quality criteria guidance
documents.    Early  Federal  efforts  were  the
"Green  Book"  (FWPCA, 1968)  and  the "Red
Book" (USEPA, 1976).  EPA also sponsored a
contract effort that resulted  in the "Blue Book"
(NAS/NAE,  1973).   These early efforts were
premised on the use of literature reviews and the
collective  scientific  judgment  of Agency and
advisory panels. However, when  faced with the
need to develop criteria for human health as well
as aquatic life, the Agency determined that new
procedures were necessary.  Continued reliance
solely on existing scientific literature was deemed
inadequate because essential  information was not
available for many pollutants.   EPA scientists
developed formal  methodologies for establishing
scientifically  defensible criteria.   These were
subjected  to  review  by the Agency's  Science
Advisory Board of outside experts and the public.
This effort culminated on November 28,  1980,
when the Agency published criteria development
guidelines for aquatic  life and for human health,
along  with criteria  for 64   toxic  pollutants
(USEPA, 1980a,b).  Since that initial publication,
the aquatic life methodology was slightly amended
(Appendix  H),  and  additional  criteria  were
proposed for public comment  and  finalized  as
Agency criteria guidance. EPA summarized the
available criteria information in the "Gold Book"
(USEPA, 1986a), which is updated from time to
time. However, the individual criteria documents
(see Appendix  I), as updated,  are the official
guidance documents.

EPA's   criteria  documents   provide   a
comprehensive toxicological evaluation  of each
chemical.   For toxic  pollutants, the documents
tabulate the relevant acute  and chronic toxicity
information for aquatic life and derive the criteria
maximum  concentrations (acute criteria) and
criteria   continuous  concentrations   (chronic
criteria) that the Agency  recommends to protect
aquatic  life resources.  The methodologies  for
these processes are described  in Appendices H
and J and outlined in sections 3.1.2 and 3.1.3 of
this Handbook.

3.1.1    State Use of EPA Criteria Documents

EPA's  water  quality criteria  documents  are
available to assist States in:

•    adopting water quality standards that include
     appropriate numeric  water  quality criteria;

•    interpreting existing  water  quality standards
     that include  narrative  "no toxics in toxic
     amounts" criteria;
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•    making listing decisions under section 304(1)
     of the CWA;

•    writing water quality-based NPDES permits
     and individual control strategies; and

•    providing certification under section 401 of
     the CWA for any Federal permit or license
     (e.g., EPA-issued NPDES permits, CWA
     section  404 permits,  or Federal  Energy
     Regulatory Commission licenses).

In these situations, States have primary authority
to determine  the appropriate  level  to protect
human health or welfare  (in  accordance with
section 303(c)(2) of the CWA) for each water
body.  However, under the Clean  Water Act,
EPA must also review and approve State water
quality standards; section 304(1) listing decisions
and draft and final State-issued individual control
strategies;  and  in  States  where  EPA  writes
NPDES permits,  EPA must develop appropriate
water quality-based permit limitations. The States
and  EPA  therefore  have  a strong  interest in
assuring that the decisions are  legally defensible,
are based on the  best information available, and
are subject to full and meaningful public comment
and participation.  It is very important that each
decision  be supported by  an  adequate record.
Such a record is critical to  meaningful comment,
EPA's review of the State's decision,  and any
subsequent administrative or judicial review.

Any human health criterion for a toxicant is based
on at least three interrelated considerations:

•    cancer potency or systemic toxicity,

•    exposure, and

•    risk characterization.

States may make  their own judgments on each of
these factors within reasonable scientific bounds,
but documentation to  support their judgments,
when different from EPA's recommendation, must
be clear and in the public record.  If a State relies
on EPA's section 304(a) criteria document (or
other EPA documents), the State may reference
and rely on the data in these documents and need
not  create  duplicative  or new  material   for
inclusion in their records.  However, where site-
specific issues arise or the State decides to adopt
an approach to any one of these three factors that
differs  from the  approach in  EPA's  criteria
document, the State must explain its reasons in a
manner sufficient for a reviewer to determine that
the approach chosen is based on  sound scientific
rationale (40 CFR 131.11(b)).

3.1.2    Criteria for Aquatic Life Protection

The development  of  national numerical water
quality  criteria for the protection  of  aquatic
organisms  is a  complex  process  that  uses
information  from   many  areas  of  aquatic
toxicology.   (See  Appendix H for  a detailed
discussion of this process.)  After a decision is
made that  a national  criterion  is  needed for a
particular  material, all available information
concerning toxicity  to, and bioaccumulation by,
aquatic organisms is collected and reviewed  for
acceptability. If enough acceptable data for 48- to
96-hour  toxicity  tests  on  aquatic  plants  and
animals are available, they are used to derive the
acute criterion.  If sufficient data on the ratio of
acute  to  chronic  toxicity  concentrations   are
available, they are used to derive the  chronic or
long-term exposure criteria. If justified, one or
both of the criteria may be related to other water
quality characteristics,  such as pH, temperature,
or hardness.  Separate  criteria are developed for
fresh waters and saltwaters.

The Water Quality  Standards Regulation allows
States to develop  numerical  criteria  or modify
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                                                                   Chapter 3 - Water Quality Criteria
EPA's  recommended criteria  to  account  for
site-specific  or  other  scientifically  defensible
factors.  (Ed. note: EPA is currently revising the
1984  guideline   for developing  site-specific
criteria.  These revisions will be made available
shortly as an update to this Handbook.)  When a
criterion must  be developed for a  chemical for
which  a  national  criterion  has  not  been
established, the regulatory authority should refer
to the EPA guidelines (Appendix H).

     Magnitude for Aquatic Life Criteria

Water quality criteria for aquatic life contain two
expressions of allowable magnitude: a criterion
maximum concentration (CMC) to protect against
acute  (short-term)   effects;  and  a  criterion
continuous concentration (CCC) to protect against
chronic (long-term) effects.   EPA  derives acute
criteria  from 48- to 96-hour tests of lethality or
immobilization.  EPA  derives  chronic  criteria
from longer term  (often greater than 28-day) tests
that measure survival, growth, reproduction, or in
some cases, bioconcentration. Where appropriate,
the calculated  criteria  may be  lowered  to be
protective of economically important species.

     Duration  for Aquatic Life Criteria

The quality of an ambient water typically varies in
response to variations of effluent quality, stream
flow, and other  factors.    Organisms  in  the
receiving water are  not experiencing  constant,
steady  exposure  but rather  are  experiencing
fluctuating exposures, including periods of high
concentrations, which may have adverse effects.
Thus, EPA's criteria indicate a time period over
which exposure is to be averaged,  as well as a
maximum  concentration, thereby  limiting  the
duration of exposure to elevated concentrations.
For acute criteria, EPA recommends an averaging
period of 1 hour.  That is, to protect against acute
effects,  the 1-hour  average  exposure should not
exceed  the CMC.   For chronic criteria,  EPA
recommends an averaging period of  4 days.  That
is, the 4-day average exposure should not exceed
the CCC.
     Frequency for Aquatic Life Criteria

To predict or ascertain the attainment of criteria,
it is necessary to specify the allowable frequency
for exceeding the criteria.  This is  because it is
statistically impossible to project that criteria will
never be exceeded.  As ecological  communities
are naturally subjected to a series of stresses,  the
allowable frequency of pollutant stress may be set
at a value that does not  significantly increase  the
frequency or severity of all stresses  combined.

EPA  recommends  an  average  frequency   for
excursions of both acute and  chronic criteria  not
to exceed once in  3 years.   In all cases,  the
recommended frequency applies to actual ambient
concentrations,  and excludes the  influence  of
measurement imprecision.  EPA established  its
recommended frequency as part of its guidelines
for deriving criteria (Appendix H).  EPA selected
the maximum  3-year  return  interval  with   the
intent of providing a degree of protection roughly
equivalent to a 7Q10 design flow condition, and
with some consideration of  rates  of ecological
recovery  from  a  variety  of severe  stresses.
Because of the nature of the ecological recovery
studies   available,   the  severity  of   criteria
excursions could not be rigorously related to  the
resulting ecological  impacts.  Nevertheless, EPA
derives its criteria intending that a single marginal
criteria excursion (i.e., a slight excursion over a
1-hour period for acute or over a 4-day period  for
chronic)  would require little  or  no  time   for
recovery.   If the frequency of marginal  criteria
excursions is not high, it can be shown that  the
frequency of severe stresses, requiring measurable
recovery periods,  would  be extremely  small.
EPA thus expects the 3-year return interval to
provide  a very high degree of protection.

3.1.3  Criteria for Human Health Protection

This section reviews EPA's procedures used to
develop assessments of human health effects in
developing water quality criteria and reference
ambient concentrations.  A more complete human
health  effects  discussion  is included  in   the
Guidelines   and  Methodology  Used  in  the
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Preparation of Health Effects Assessment Chapters
of  the  Consent  Decree  Water  Documents
(Appendix J).   The procedures contained in this
document are  used  in  the  development  and
updating of EPA water quality criteria and may be
used in updating State criteria and in developing
State  criteria for those pollutants lacking  EPA
human health criteria.  The procedures may also
be  applied  as  site-specific  interpretations  of
narrative standards and as a basis for permit limits
under 40 CFR 122.44 (d)(l)(vi).

     Magnitude and Duration

Water quality criteria for human health  contain
only a single expression of allowable magnitude;
a  criterion  concentration  generally to  protect
against long-term (chronic) human health  effects.
Currently, national policy and prevailing  opinion
in  the expert  community  establish  that the
duration for human health criteria for carcinogens
should be derived assuming lifetime exposure,
taken to be a 70-year time period.  The duration
of  exposure  assumed in  deriving criteria for
noncarcinogens is more complicated owing to a
wide  variety  of endpoints:  some developmental
(and  thus  age-specific  and   perhaps   gender-
specific),  some  lifetime,  and some, such  as
organoleptic effects, not duration-related at all.
Thus,   appropriate  durations  depend   on the
individual  noncarcinogenic pollutants and the
endpoints or adverse effects being considered.

     Human Exposure Considerations

A complete human exposure evaluation for toxic
pollutants of concern for bioaccumulation would
encompass not only estimates of exposures due to
fish  consumption   but   also  exposure  from
background concentrations  and other exposure
routes,  The more  important of these  include
recreational  and occupational contact,  dietary
intake  from  other than  fish, intake  from  air
inhalation, and drinking water consumption. For
section 304(a) criteria development, EPA typically
considers only exposures to a pollutant that  occur
through the ingestion of water and contaminated
fish and shellfish.  This is the exposure default
assumption, although the human health guidelines
provide for considering other sources where data
are available (see 45 F.R. 79354).   Thus the
criteria  are based  on  an assessment  of risks
related to the surface water exposure route only
(57 F.R. 60862-3).

The consumption of contaminated fish tissue is of
serious  concern because  the  presence of even
extremely  low  ambient   concentrations  of
bioaccumulative pollutants (sublethal to aquatic
life) in  surface  waters can  result in  residue
concentrations in fish tissue that can pose a human
health  risk.  Other exposure route  information
should be considered and incorporated in human
exposure evaluations to the extent available.

Levels   of  actual   human  exposures   from
consuming contaminated fish vary depending upon
a number of case-specific consumption factors.
These   factors   include  type  of   fish  species
consumed, type of fish tissue consumed,  tissue
lipid content, consumption rate and pattern, and
food preparation practices. In addition, depending
on  the spatial variability in the fishery area, the
behavior of the fish  species, and  the point of
application of the criterion, the average exposure
of  fish may be only a  small  fraction  of the
expected exposure at the point of application of
the criterion.   If an effluent attracts fish, the
average  exposure  might  be greater  than the
expected exposure.

With shellfish, such  as  oysters,   snails, and
mussels,   whole-body    tissue  consumption
commonly occurs,  whereas with  fish, muscle
tissue and  roe  are most commonly eaten.  This
difference in the types  of tissues consumed has
implications  for   the   amount  of   available
bioaccumulative  contaminants  likely  to  be
ingested.    Whole-body  shellfish  consumption
presumably means ingestion of the entire burden
of bioaccumulative contaminants. However, with
most fish, selective  cleaning and  removal of
internal organs, and sometimes body fat as well,
from edible tissues,  may result in removal of
much   of   the  lipid   material    in    which
bioaccumulative contaminants tend to concentrate.
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                                       (9/15/93)

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                                                                  Chapter 3 - Water Quality Criteria
     Fish Consumption Values

EPA's  human health  criteria  have assumed  a
human body weight of 70 kg and the consumption
of 6.5 g of fish and shellfish per day.  Based on
data collected in 1973-74, the national per capita
consumption of freshwater and estuarine fish was
estimated to  average  6.5 g/day.   Per  capita
consumption  of all seafood (including  marine
species)  was estimated to average 14.3 g/day.
The 95th percentile for consumption of all seafood
by  individuals over a period of  1  month  was
estimated to be 42  g/day. The mean lipid content
of  fish  tissue  consumed  in  this  study  was
estimated to be 3.0 percent (USEPA, 1980c).

Currently,  four  levels  of fish  consumption are
provided in EPA guidance (USEPA, 1991a):

•    6.5 g/day to represent an estimate of average
     consumption  of  fish  and shellfish  from
     estuarine and  fresh waters by the entire U.S.
     population.  This  fish consumption level is
     based on the average of both consumers and
     nonconsumers of fish.

•    20 g/day to  represent an  estimate of the
     average  consumption of fish and shellfish
     from marine,  estuarine,  and freshwaters by
     the U.S. population.   This  average  fish
     consumption   level  also   includes   both
     consumers and nonconsumers  of fish.

•    165 g/day to  represent consumption of fish
     and shellfish  from  marine, estuarine,  and
     freshwaters by the 99.9th  percentile of the
     U.S. population consuming the most fish or
     seafood.

•    180 g/day to  represent  a "reasonable worst
     case"  based on the assumption that some
     individuals  would  consume fish at a rate
     equal  to the combined  consumption of red
     meat,  poultry,  fish, and  shellfish  in the
     United States.

EPA is  currently updating the national  estuarine
and  freshwater fish and shellfish consumption
default  values and  will  provide  a range  of
recommended national consumption values.  This
range will include:

•    mean values appropriate to the population at
     large; and

•    values appropriate for those individuals who
     consume a relatively large proportion of fish
     in   their   diets   (maximally  exposed
     individuals).

Many States  use  EPA's 6.5 g/day consumption
value.   However, some States  use  the  above-
mentioned 20 g/day value and, for saltwaters,
37 g/day. In general, EPA recommends that the
consumption values used in deriving criteria from
the formulas  in  this chapter reflect the most
current, relevant,  and/or site-specific information
available.

     Bioaccumulation Considerations

The ratio of the contaminant concentrations in fish
tissue versus  that in water is termed either the
bioconcentration   factor   (BCF)   or   the
bioaccumulation factor (BAF). Bioconcentration
is defined as  involving contaminant uptake from
water only (not from food). The bioaccumulation
factor (BAF)  is  defined similarly to the BCF
except that it  includes contaminant uptake from
both  water   and food.     Under  laboratory
conditions,    measurements   of   tissue/water
partitioning are generally  considered to involve
uptake from water only.  On the other hand, both
processes are  likely to apply in the field since the
entire food chain is exposed.

The BAF/BCF ratio ranges from 1 to 100, with
the highest ratios applying to organisms in higher
trophic levels, and to chemicals with logarithm of
the octanol-water  partitioning coefficient (log P)
close to  6.5.

Bioaccumulation considerations are integrated into
the criteria   equations  by  using  food chain
multipliers (FMs) in conjunction with the BCF.
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                                         3-5

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Water Quality Standards Handbook - Second Edition
The bioaccumulation and bioconcentration factors '
for a chemical are related as follows:
BAF = FM x BCF

By incorporating the FM and BCF terms into the
criteria equations, bioaccumulation can be
addressed.

In Table 3-1, FM values derived from the work
of Thomann (1987, 1989) are listed according to
log P value and trophic level of the organism.
For chemicals with log P values greater than
about 7, there is additional uncertainty regarding
the degree of bioaccumulation, but generally,
trophic level effects appear to decrease due to
slow transport kinetics of these chemicals in fish,
the growth rate of the fish, and the chemical's
V '
relatively low bioavailability. Trophic level 4
organisms are typically the most desirable species
for sport fishing and, therefore, FMs for trophic
level 4 should generally be used in the equations
for calculating criteria. In those very rare
situations where only lower trophic level
organisms are found, e.g., possibly oyster beds,
an FM for a lower trophic level might be
considered.

Measured BAFs (especially for those chemicals
with log P values above 6.5) reported in the
literature should be used when available. To use
A.vnA«*imA**+n11«r **tA<'iriit«*Asl T3 A ~Ct* iv\ /*»«)1/*li1o+l« rr +VlO








Trophic Levels
LogP
33 •
3.6
3,7
3,8
3,9
4,0
4.1
4,2
4.3
4.4
4.5 .
4 6
^•W
4.7
4.8
4.9
5.0
5.1
5.2
5.3
5.4
5.5
5.6
5.7
5.8
5.9
6.0
6.1
6.2
6.3
6.4
6,5
&&5
!2
1,0
1.0
3.0
1.0
3.0
I.I
1.1
1.1
1.2
1 1
-&.*Ar
1.3
1.4
;1.5
1.6
1.7
:2,2
2.4
2,8
3,3
3.9
4.6
5.6
6.8
8.2
10
13
;15

;#,r
3
1.0
1.0
1,0
1,0
1,0
1,0
1.1
1.1
1.1
1.1
1.2 =
1.3
1.4 :
1.5
1.8
2.1
2.5
3.0
3.7
4.6
5.9
7.5
9.8 :
13
17
21
25
29
34 ;
39
45
45' ;
4
1.0
i 1.0
: 1.0
1*0
1.0
1.0
I.I
I.I
1.1
1.1
1.2
! 3
.!.*•?
1.4
1.6
2.0
2.6
3,2
4.3
5,8
8,0
II
16
23
33
47
67
75
84
92
98
100
100"
criterion, the (FM x BCF) term is replaced by the
BAF in the equations in the following  section.
Relatively  few  BAFs  have  been  measured
accurately and reported, and their application to
sites other than the specific ecosystem where they
were developed  is problematic  and subject  to
uncertainty.   The  option is also available  to
develop BAFs experimentally, but this  will  be
extremely resource intensive  if done on a site-
specific basis with all the necessary experimental
and quality controls.
  * These recommended FMs are conservative estimates;
  FMs for log P values greater than 6.5 may range front
  the values given to as low as 0.1 for contaminants with
  very low bioavailability.          ;
Table 3-1.    Estimated   Food   Chain
              Multipliers (FMs)
                                                      Updating Human Health Criteria Using
                                                      DOS

                                                 EPA recommends that States use the most current
                                                 risk information in the process of updating human
3-6
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                                                                  Chapter 3 - Water Quality Criteria
health criteria.  The Integrated Risk Information
System   (IRIS)  (Barns  and  Dourson,  1988;
Appendix N)  is an  electronic data base of the
USEPA  that  provides  chemical-specific  risk
information on the relationship between chemical
exposure and estimated human health effects. Risk
assessment information contained in IRIS, except
as  specifically noted, has  been reviewed and
agreed upon by  an  interdisciplinary group  of
scientists representing various Program Offices
within the Agency and represent an Agency-wide
consensus.    Risk assessment information and
values are  updated on a monthly basis and are
approved for Agency-wide use. IRIS is intended
to  make  risk assessment  information  readily
available to those individuals who must perform
risk assessments and also to increase consistency
among   risk   assessment/risk   management
decisions.

IRIS  contains two  types of  quantitative  risks
values:  the oral Reference  Dose (RfD) and the
carcinogenic  potency estimate or  slope factor.
The RfD (formerly known as the acceptable daily
intake or  ADI)  is  the human  health  hazard
assessment for noncarcinogenic (target organ)
effects.    The carcinogenic  potency  estimate
(formerly known  as  q,*) represents  the  upper
bound cancer-causing potential resulting  from
lifetime exposure to a substance.  The RfD or the
oral carcinogenic potency estimate is used in the
derivation of EPA human health criteria.

EPA   periodically  updates  risk   assessment
information,  including  RfDs, cancer  potency
estimates, and related information on contaminant
effects,  and reports  the current information on
IRIS.  Since IRIS contains the Agency's  most
recent quantitative risk assessment values, current
IRIS values should be used by States in updating
or developing new human health criteria.  This
means that  the 1980 human health criteria should
be  updated  with  the latest  IRIS values.   The
procedure for deriving an  updated human health
water quality criterion would require inserting the
current Rfd or carcinogenic  potency estimate on
IRIS into the equations in Exhibit 3.1 or 3.2, as
appropriate.
                    EPA's
                 water quality
                   criterion
                   available
                             Evaluate other
                             sources of data,
                             e.g., FDA action
                             levels, MCLs, risk
                             assessment, fish
                             consumption
                             advisory levels
Figure 3-1.   Procedure for  determining an
              updated  criterion  using  IRIS
              data.

Figure 3-1 shows the procedure for determining
an  updated criterion  using  IRIS data.   If  a
chemical   has  both  carcinogenic  and   non-
carcinogenic effects, i.e., both a cancer potency
estimate  and a  RfD, both  criteria should be
calculated. The most stringent criterion applies.

     Calculating Criteria for Non-carcinogens

The RfD is an estimate of the daily exposure to
the human population that is likely to be without
appreciable risk of causing  deleterious effects
during a lifetime.  The RfD is expressed in units
of mg toxicant per  kg human  body weight per
day.

RfDs are derived from the "no-observed-adverse-
effect level" (NOAEL) or the "lowest-observed-
adverse-effect  level"  (LOAEL)  identified from
chronic or subchronic human epidemiology studies
or animal exposure  studies.  (Note: "LOAEL"
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and  "NOAEL"  refer  to  animal  and  human
toxicology  and are therefore  distinct  from the
aquatic   toxicity   terms   "no-observed-effect
concentration"  (NOEC)  and  "lowest-observed-
effect  concentration"  (LOEC).)   Uncertainty
factors are then applied to the NOAEL or LOAEL
to account for uncertainties in the data associated
with variability among individuals, extrapolation
from nonhuman test species to humans, data on
other than long-term exposures, and the use of a
LOAEL  (USEPA,   1988a).     An  additional
uncertainty factor may be applied to account for
significant weakness or gaps in the database.

The  RfD is  a threshold below  which systemic
toxic  effects  are  unlikely to  occur.   While
exposures above the RfD increase the probability
of adverse effects, they do not produce a certainty
of adverse effects.  Similarly, while exposure at
or below the RfD reduces the probability, it does
not guarantee the absence of effects in all persons.
The  RfDs  contained in  IRIS are values  that
represent EPA's consensus  (and have uncertainty
spanning perhaps  an order of magnitude).  This
means an RfD of 1.0 mg/kg/day could range from
0.3 to 3.0 mg/kg/day.

For noncarcinogenic effects, an updated criterion
can be derived using the equation in Exhibit 3-1.

If the  receiving water body  is  not used  as a
drinking  water source,  the  factor WI can  be
deleted.    Where   dietary  and/or  inhalation
exposure values are unknown, these factors may
be deleted from the above calculation.

     Calculating Criteria for Carcinogens

Any human health  criterion for a carcinogen is
based on at least three interrelated considerations:
cancer   potency,    exposure,  and   risk
characterization. When developing State criteria,
States may  make their own judgments on each of
these factors  within reasonable scientific bounds,
but documentation  to support  their judgments
must be clear and in the public record.
Maximum protection of human health from the
potential effects  of  exposure  to carcinogens
through the consumption of contaminated  fish
and/or other aquatic life would require a criterion
of zero.   The  zero  level  is  based  upon the
assumption of nonthreshold effects (i.e., no  safe
level exists below which any increase in exposure
does not result in an increased risk of cancer) for
carcinogens.    However,  because  a  publicly
acceptable policy for safety  does not require the
absence of  all  risk,  a  numerical estimate of
pollutant   concentration    (in    /^g/1)    which
corresponds to  a given  level  of risk  for  a
population of a specified size is selected instead.
A cancer risk  level is defined as the number of
new  cancers that may  result in  a population of
specified size  due  to  an increase in  exposure
(e.g., 10"6 risk level =  1 additional cancer  in a
population of 1 million). Cancer risk is calculated
by multiplying the experimentally derived cancer
potency estimate by  the concentration  of the
chemical in the fish and the average daily human
consumption of contaminated fish.  The risk for a
specified population (e.g., 1 million people or 10"
6) is then calculated by dividing the risk level by
the specific  cancer  risk.   EPA's ambient water
quality  criteria  documents  provide risk  levels
ranging from 10~5 to 10~7  as  examples.

The  cancer potency estimate,  or  slope  factor
(formerly  known as the qj*),  is derived using
animal  studies.    High-dose  exposures  are
extrapolated  to  low-dose  concentrations  and
adjusted to a lifetime exposure period through the
use of a linearized multistage model. The model
calculates the upper 95 percent confidence limit of
the slope  of  a straight  line which the  model
postulates  to occur at low doses. When based on
human (epidemiological) data, the slope factor is
based on the observed increase in cancer risk and
is not extrapolated.   For deriving criteria for
carcinogens, the oral cancer potency estimates or
slope factors from IRIS are used.

It is important to note that cancer potency factors
may overestimate or underestimate the actual risk.
Such  potency  estimates  are subject to  great
uncertainty because of two primary factors:
3-8
                                      (9/15/93)

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                                                                   Chapter 3 - Water Quality Criteria
         C (mg/l)   a*
                  X
• flDT -t- IN) x WT
    where:
         WI + [FCxLxFMx BCFJ


C     =    updated water quality criterion (mg/1)

RfD   =    oral reference dose (mg toxicant/kg human body weight/day)

WT   =    weight of an average human adult (70 kg)

DT    »    dietary exposure  (other than  fish) (mg  toxicant/kg  body  human
             weight/day)

IN     =    inhalation exposure (mg toxicant/kg body human weight/day)

WI    =    average human adult water intake (2 I/day)

FC    =    daily fish consumption (kg fish/day)

L     =    ratio of lipid fraction of fish tissue consumed to 3%

FM    =    food chain multiplier (from Table 3-1)

BCF   —    bioconcentration factor (mg toxicant/kg fish divided by mg toxicant/L
             water) for fish with 3% lipid content
  Exhibit 3-1.  Equation for Deriving Human Health Criteria Based on Noncarcinogenic Effects
•    adequacy  of the cancer  data base  (i.e.,
     human vs. animal data); and

•    limited information regarding the mechanism
     of cancer causation.

Risk levels of 10'5, lO'6,  and 10'7 are often used
by States as minimal risk  levels in interpreting
their  standards.   EPA  considers  risks  to  be
additive, i.e., the risk from individual chemicals
is not necessarily the overall risk from exposure
to water. For example, an individual risk level of
10"6  may yield  a higher  overall risk  level  if
multiple carcinogenic chemicals are present.

For  carcinogenic  effects,  the criterion can  be
determined by using  the equation in Exhibit 3-2.
                                      If the receiving water body is not designated as a
                                      drinking  water  source,  the factor  WI  can be
                                      deleted.

                                          Deriving Quantitative Risk Assessments  in
                                          the Absence of IRIS Values

                                      The RfDs or cancer potency estimates  comprise
                                      the existing dose-response factors for developing
                                      criteria.    When  IMS  data  are   unavailable,
                                      quantitative  risk  level   information  may  be
                                      developed according to a State's own procedures.
                                      Some   States   have  established   their  own
                                      procedures whereby dose-response factors can be
                                      developed based  upon  extrapolation  of  acute
                                      and/or chronic animal data  to  concentrations  of
                                      exposure protective  of  fish  consumption  by
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                                                                               3-9

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Water Quality Standards Handbook - Second Edition
    where:
c

RL ;   »

WT   «

qt*    -

wi    «

FC

L   •   =

FM   =

BCF   -
                                OIL IE WD
                       [WI + WC K L x CFM x
                       updated water quality criterion (mg/I)   :

                       risk level (10*) where x is usually in the range of 4 to 6

                       weight of an average human adult (70 kg)

                       carcinogenic potency factor (kg day/rag) i

                       average human adult water intake (2 I/day)

                       daily fish consumption (kg fish/day)

                       ratio of lipid fraction of fish tissue consumed to 3% assumed by EPA

                       food chain multiplier (from Table 3-1)                  ;

                       bioconcentration factor (mg toxicant/kg fish divided by tng toxicant/L
                       water) for fish with 3%  lipid content
  Exhibit 3-2.  Equation for Deriving Human Health Criteria Based on Carcinogenic Effects
humans.
       Relationship of Section 304(a) Criteria
       to State Designated Uses
The section 304(a)(l) criteria published by EPA
from time to  time can be used to support  the
designated uses  found in  State standards.   The
following sections briefly discuss the relationship
between  certain  criteria  and  individual   use
classifications.   Additional information  on this
subject also can be found in the "Green Book"
(FWPCA, 1968); the "Blue Book" (NAS/NAE,
1973); the "Red Book" USEPA,  1976); the EPA
Water Quality Criteria Documents (see Appendix
I); the"Gold Book" (USEPA, 1986a); and future
EPA  section  304(a)(l)  water  quality  criteria
publications.
                                     Where a water body is designated for more than
                                     one use, criteria necessary to  protect the most
                                     sensitive use must be applied. The following four
                                     sections discuss the major types of use categories.
                                     3.2.1  Recreation

                                     Recreational uses of water include activities such
                                     as  swimming,  wading,  boating, and fishing.
                                     Often insufficient data exist on the human health
                                     effects  of physical  and  chemical  pollutants,
                                     including most toxics, to make a determination of
                                     criteria for  recreational  uses. However,  as  a
                                     general guideline, recreational waters that contain
                                     chemicals in concentrations toxic or  otherwise
                                     harmful to man if ingested, or irritating to the
                                     skin or mucous membranes of the human body
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 upon brief immersion,  should be avoided.  The
 section 304(a)(l) human health effects criteria
 based on direct human drinking  water intake and
 fish consumption might provide useful guidance in
 these  circumstances.   Also, section  304(a)(l)
 criteria based  on human health effects  may be
 used to support this designated use where fishing
 is included in the State definition of "recreation."
 In  this latter situation, only the portion of the
 criterion based on fish consumption should be
 used.   Section   304(a)(l)  criteria  to  protect
 recreational  uses  are also available for certain
 physical,  microbiological,  and   narrative  "free
 from" aesthetic criteria.

 Research regarding bacteriological indicators has
 resulted in  EPA recommending that States use
 Escherichia coli  or  enterococci  as  indicators of
 recreational water quality (USEPA, 1986b) rather
 than  fecal   coliform   because   of  the  better
 correlation with gastroenteritis in swimmers.

 The  "Green Book" and "Blue  Book"  provide
 additional information on protecting recreational
 uses such as pH criteria to prevent eye irritation
 and microbiological criteria based  on aesthetic
 considerations.

 3.2.2  Aquatic Life and Wildlife

 The section  304(a)(l)  criteria  for  aquatic life
 should be used directly to support this designated
 use.   If subcategories  of this use are adopted
 (e.g.,  to  differentiate  between  coldwater  and
 warmwater  fisheries), then appropriate  criteria
 should be set to reflect the varying needs of such
 subcategories.

 3.2.3  Agricultural and Industrial Uses

 The "Green  Book" (FWPCA, 1968) and "Blue
 Book"  (NAS/NAE,   1973)   provide   some
 information   on   protecting  agricultural   and
 industrial  uses.   Section 304(a)(l)  criteria for
protecting these uses have not been specifically
developed for numerous parameters pertaining to
these uses, including most toxics.
 Where   criteria  have  not  been  specifically
 developed for these uses, the criteria developed
 for human health  and aquatic  life are usually
 sufficiently stringent to protect these uses. States
 may also establish criteria specifically designed to
 protect these uses.

 3.2.4  Public Water Supply

 The drinking water exposure component of the
 section 304(a)(l) criteria based on human health
 effects can apply directly to this use classification.
 The criteria also may  be appropriately  modified
 depending upon whether the specific water supply
 system  falls within the  auspices  of  the  Safe
 Drinking Water Act's (SDWA) regulatory control
 and the type and level of treatment imposed upon
 the supply before delivery to the consumer.  The
 SDWA controls the presence of contaminants in
 finished  ("at-the-tap") drinking water.

 A brief  description of relevant sections of the
 SDWA is necessary to explain how the Act will
 work in conjunction with section 304(a)(l) criteria
 in protecting human health  from  the effects  of
 toxics due to consumption of water.  Pursuant to
 section 1412 of the SDWA, EPA has promulgated
 "National Primary Drinking Water Standards" for
 certain radionuclide, microbiological, organic, and
 inorganic substances.  These standards  establish
 maximum  contaminant levels  (MCLs),  which
 specify   the  maximum permissible  level  of a
 contaminant in  water that may be delivered to a
 user of a  public water system  now defined  as
 serving  a  minimum of 25  people.  MCLs are
 established based on consideration of a  range  of
 factors including not only the health effects of the
 contaminants  but  also  treatment  capability,
 monitoring availability, and costs. Under section
 1401(l)(D)(i) of the SDWA, EPA is also allowed
 to establish the minimum quality criteria for water
 that  may be taken into a public  water supply
 system.

 Section  304(a)(l)  criteria provide  estimates of
pollutant  concentrations protective  of human
health, but do not consider treatment technology,
costs, and other feasibility  factors.  The section
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304(a)(l)   criteria   also   include   fish
bioaccumulation  and  consumption  factors  in
addition to direct human drinking water intake.
These numbers were not developed to serve as
"at-the-tap"  drinking water standards, and  they
have no regulatory significance under the SDWA.
Drinking water standards are established based on
considerations,  including    technological   and
economic feasibility,  not  relevant  to  section
304(a)(l) criteria.  Section  304(a)(l) criteria are
more analogous to  the  maximum contaminant
level  goals  (MCLGs)  (previously  known  as
RMCLs)  under section  1412(b)(l)(B)  of  the
SDWA  in which, based  upon a report from the
National Academy of Sciences, the Administrator
should  set  target  levels  for  contaminants  in
drinking water at which "no known or anticipated
adverse effects occur and which allow an adequate
margin of safety."  MCLGs do not take treatment,
cost,   and    other   feasibility   factors   into
consideration.  Section 304(a)(l) criteria are, in
concept, related to the health-based goals specified
in the MCLGs.

MCLs of the SDWA, where they exist, control
toxic  chemicals  in  finished  drinking water.
However, because  of variations  in   treatment,
ambient water criteria may be used by the States
as a supplement to  SDWA regulations.  When
setting water quality  criteria for  public water
supplies,  States have the  option  of applying
MCLs,  section 304(a)(l) human  health effects
criteria, modified  section 304(a)(l) criteria,  or
controls more stringent than these three to protect
against the effects of contaminants by ingestion
from drinking water.

For treated  drinking water supplies  serving  25
people   or   greater,   States   must  control
contaminants down to levels  at least as stringent
as MCLs  (where  they exist for the pollutants of
concern)  in   the   finished  drinking  water.
However, States also have  the options to control
toxics in the ambient water by choosing section
304(a)(l)  criteria,   adjusted  section  304(a)(l)
criteria resulting from the reduction of the direct
drinking water exposure component in the criteria
calculation to the extent that the treatment process
reduces the level of pollutants, or a more stringent
contaminant level than the former three options.
       State Criteria Requirements
Section 131.11(a)(l) of the Regulation requires
States to adopt water quality criteria to protect the
designated use(s).  The State criteria must be
based  on  sound scientific rationale  and must
contain sufficient parameters  or constituents  to
protect the designated  use(s).  For waters  with
multiple  use  designations,  the  criteria  must
support the most sensitive use.

In section 131.11, States are encouraged to adopt
both numeric and narrative criteria.  Aquatic life
criteria should  protect against  both short-term
(acute) and long-term (chronic) effects.  Numeric
criteria are particularly important where the cause
of toxicity is known  or  for  protection against
pollutants with potential human health impacts or
bioaccumulation potential. Numeric water quality
criteria may  also be  the  best  way  to  address
nonpoint source pollution  problems.   Narrative
criteria can be the  basis for limiting toxicity in
waste discharges where a specific pollutant can be
identified as causing or contributing to the toxicity
but where there are no  numeric  criteria in the
State standards.  Narrative criteria also can be
used  where   toxicity  cannot  be  traced  to  a
particular pollutant.

Section 131.11(a)(2) requires States to  develop
implementation procedures which explain how the
State will ensure that narrative toxics criteria are
met.

To more fully protect aquatic habitats, it is EPA's
policy that States fully integrate chemical-specific,
whole-effluent,   and   biological   assessment
approaches in State water  quality programs (see
Appendix R).  Specifically, each of these three
methods  can  provide a  valid  assessment  of
designated   aquatic   life   use   impairment.
Therefore, EPA supports a policy of independent
application of these  three water quality assessment
approaches.  Independent application means that
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                                                                    Chapter 3 - Water Quality Criteria
the validity  of the results of any one of the
approaches does not depend on confirmation by
one or both of the other methods. This policy is
based on the unique attributes,  limitations, and
program  applications  of  each  of  the  three
approaches.  Each method alone can provide valid
and   independently   sufficient   evidence  of
attainment or  non-attainment  of water  quality
standards,  irrespective  of any  evidence,  or lack
thereof, derived from the other two approaches.
The failure of one method  to confirm impacts
identified by another method does not negate the
results of the initial assessment (USEPA,  1991i).

It is  also   EPA's policy  that  States  should
designate aquatic  life  uses  that  appropriately
address biological integrity and adopt biological
criteria necessary  to  protect those  uses (see
section 3.5.3 and Appendices C,  K, and R).
       Criteria for Toxicants
Applicable requirements  for State  adoption of
water quality criteria for toxicants vary depending
upon the toxicant. The reason for this is that the
1983  Water  Quality   Standards   Regulation
(Appendix A) and the Water Quality Act of 1987
which amended the Clean Water Act (Public Law
100-4) include more specific requirements for the
particular  toxicants  listed  pursuant  to  CWA
section 307(a). For regulatory purposes, EPA has
translated  the 65 compounds and  families of
compounds listed pursuant to section 307(a)  into
126 more specific substances, which EPA refers
to as "priority toxic pollutants."  The 126 priority
toxic pollutants are listed in the WQS regulation
and in Appendix P of this Handbook. Because of
the more specific requirements for priority toxic
pollutants,  it is  convenient  to  organize  the
requirements  applicable  to State adoption  of
criteria for toxicants into three categories:

•    requirements applicable to  priority toxic
     pollutants that have been the subject of CWA
     section  304(a)(l) criteria  guidance  (see
     section 3.4.1);
•    requirements applicable to  priority  toxic
     pollutants that have not been the subject of
     CWA section 304(a)(l) criteria guidance (see
     section 3.4.1);  and

•    requirements applicable to all other toxicants
     (e.g.,   non-conventional   pollutants   like
     ammonia and chlorine) (see section 3.4.2).

3.4.1  Priority Toxic Pollutant Criteria

The criteria  requirements applicable to priority
toxic pollutants  (i.e., the first  two  categories
above) are specified in CWA section 303(c)(2)(B).
Section 303(c)(2)(B),  as added by  the Water
Quality Act of 1987, provides that:

     Whenever a  State reviews water quality
     standards pursuant to paragraph  (1) of
     this  subsection,  or revises  or  adopts
     new   standards  pursuant   to   this
     paragraph,  such  State  shall   adopt
     criteria  for  all  toxic  pollutants listed
     pursuant to section 307(a)(l) of this Act
     for which criteria have been published
     under section 304(a), the discharge or
     presence  of which in  the affected
     waters could reasonably be  expected to
     interfere with  those  designated uses
     adopted by  the State, as necessary to
     support  such designated uses.    Such
     criteria  shall  be  specific  numerical
     criteria   for  such  toxic   pollutants.
     Where such  numerical  criteria are not
     available,  whenever a  State reviews
     water quality  standards pursuant to
     paragraph (1), or revises or adopts new
     standards  pursuant  to this  paragraph,
     such  State shall adopt criteria based on
     biological monitoring  or  assessment
     methods  consistent with  information
     published pursuant to section 304(a)(8).
     Nothing  in   this  section  shall be
     construed  to limit or delay  the  use of
     effluent  limitations or  other  permit
     conditions  based   on   or  involving
     biological monitoring  or  assessment
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Water Quality Standards Handbook - Second Edition
     methods   or   previously   adopted
     numerical criteria.

EPA,   in   devising   guidance   for   section
303(c)(2)(B), attempted to provide States with the
maximum  flexibility  that  complied  with  the
express  statutory  language  but  also  with  the
overriding  congressional  objective:    prompt
adoption and  implementation of numeric  toxics
criteria.    EPA  believed that  flexibility  was
important so that each State could comply with
section  303(c)(2)(B) and to the extent possible,
accommodate its existing water quality standards
regulatory approach.

     General Requirements

To  carry  out the   requirements   of  section
303(c)(2)(B), whenever a State revises its water
quality  standards,  it  must review all available
information and data to first determine whether
the discharge or the presence of a toxic pollutant
is interfering with or is likely to interfere with the
attainment of the designated uses of any water
body segment.

If the data indicate that it is reasonable to expect
the toxic pollutant to interfere with the use, or it
actually is interfering with the use, then the State
must adopt  a numeric limit  for the specific
pollutant.  If a State is unsure whether a toxic
pollutant  is  interfering with,  or is  likely to
interfere with, the designated use and  therefore is
unsure that control of the pollutant is necessary to
support  the  designated use,  the  State should
undertake to develop sufficient information upon
which to make such a determination. Presence of
facilities that manufacture or  use the  section
307(a)  toxic pollutants  or  other information
indicating that such  pollutants are  discharged  or
will be  discharged  strongly  suggests that such
pollutants  could be interfering with attaining
designated  uses.  If  a State expects the pollutant
not to interfere  with the designated use, then
section 303(1)(2)(B) does not require a  numeric
standard for that pollutant.

Section  303(c)(2)(B) addresses  only pollutants
listed as  "toxic" pursuant to section 307(a) of the
Act,  which are codified at 40 CFR  131.36(b).
The section 307(a) list contains 65 compounds and
families of compounds, which potentially include
thousands of specific compounds.  The Agency
has interpreted that list to include 126 "priority"
toxic   pollutants    for   regulatory   purposes.
Reference in this guidance to toxic pollutants  or
section 307(a) toxic  pollutants refers to the 126
priority toxic pollutants unless otherwise noted.
Both  the list of priority toxic pollutants and
recommended criteria levels are subject to change.

The national criteria recommendations published
by  EPA under section 304(a) (see section 3.1,
above) of the Act include values for both  acute
and chronic aquatic  life protection; only chronic
criteria recommendations have been established to
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                                                                    Chapter 3 - Water Quality Criteria
 protect  human  health.   To comply with  the
 statute,  a State  needs to  adopt aquatic life and
 human health criteria where necessary to support
 the appropriate designated uses.  Criteria for the
 protection of human health are needed for water
 bodies designated for public water supply. When
 fish ingestion is  considered an important activity,
 then  the human  health-related water  quality
 criteria recommendation developed under section
 304(a) of the CWA  should  be used;  that is,  the
 portion of the criteria  recommendation based on
 fish consumption. For those pollutants designated
 as carcinogens, the recommendation for a human
 health criterion  is generally more stringent than
 the aquatic life criterion  for the  same pollutant.
 In   contrast,   the   aquatic   life   criteria
 recommendations   for   noncarcinogens   are
 generally more  stringent than the human health
 recommendations.  When a State adopts a human
 health criterion for a carcinogen,  the State needs
 to select a risk  level.  EPA has estimated risk
 levels of 10'5,  10'6,  and  ICr7  in  its  criteria
 documents under one set of exposure assumptions.
 However, the State  is not  limited to choosing
 among the risk  levels published in  the  section
 304(a) criteria documents,  nor is the State limited
 to the base case exposure assumptions; it must
 choose the risk level for its conditions and explain
 its rationale.

 EPA generally  regulates  pollutants   treated  as
 carcinogens in the range of 10~6 to 10^ to protect
 average  exposed individuals and more  highly
 exposed  populations.  However, if a State selects
 a  criterion that represents an  upper  bound risk
 level less protective than 1 in 100,000 (e.g., 10'5),
 the State needs to have substantial support in the
 record for this level. This support focuses on two
 distinct issues.   First,  the record must include
 documentation that the decision maker considered
 the public interest of the State in selecting the risk
 level,   including  documentation  of   public
participation  in the decision making  process  as
required   by   the   Water  Quality   Standards
Regulation at 40 CFR  131.20(b).  Second, the
record must include an  analysis  showing that the
risk level selected, when combined with other risk
assessment variables, is a balanced and reasonable
 estimate of actual risk posed, based on the best
 and  most representative  information  available.
 The  importance  of the  estimated  actual  risk
 increases as  the  degree  of conservatism  in the
 selected risk level diminishes.   EPA carefully
 evaluates all  assumptions used by a State if the
 State chose to alter any one of the standard EPA
 assumption values (57 F.R. 60864, December 22,
 1993).

 EPA does not intend to  propose changes to the
 current requirements regarding the bases on which
 a State can  adopt numeric  criteria  (40  CFR
 131.11(b)(l)).  Under   EPA's  regulation,   in
 addition to basing numeric criteria  on EPA's
 section 304(a) criteria documents, States may also
 base   numeric   criteria   on   site-specific
 determinations or  other scientifically defensible
 methods.

 EPA expects  each State to comply with the  new
 statutory requirements in any section 303(c) water
 quality standards review initiated after enactment
 of the Water Quality  Act of 1987.  The structure
 of section  303 (c) is to require States to review
 their water quality standards at least once each 3
 year period.  Section 303(c)(2)(B) instructs States
 to include reviews for toxics criteria  whenever
 they initiate a triennial  review.  Therefore, even
 if a State has complied with section 303(c)(2)(B),
 the State must review its standards each triennium
 to ensure that section 303(c)(2)(B) requirements
 continue to be  met,  considering that EPA may
 have  published additional  section 304(a) criteria
 documents and  that  the  State will have  new
 information on  existing  water quality and  on
 pollution sources.

 It should be noted that nothing in the Act or in the
 Water Quality Standards Regulation restricts the
 right of a State to adopt numeric criteria for  any
pollutant not listed pursuant to section 307(a)(l),
 and  that  such  criteria  may  be expressed  as
concentration limits for an individual pollutant or
 for a toxicity parameter  itself as  measured  by
whole-effluent toxicity testing.  However, neither
numeric toxic  criteria nor whole-effluent toxicity
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should be used as a surrogate for, or to supersede
the other.

     State Options

States may meet the requirements of CWA section
303(c)(2)(B)   by    choosing   one  of  three
scientifically  and  technically sound options (r-
some combination  thereof):
or
(1)  Adopt  statewide  numeric criteria in State
     water quality standards for all section 307(a)
     toxic   pollutants   for  which  EPA   has
     developed criteria guidance,  regardless of
     whether  the  pollutants are  known to be
     present;

(2)  Adopt  specific numeric  criteria  in State
     water quality standards for section  307(a)
     toxic  pollutants  as  necessary  to  support
     designated  uses where  such pollutants are
     discharged  or  are present  in  the affected
     waters  and  could  reasonably be expected to
     interfere  with designated uses;

(3)  Adopt a "translator procedure" to be applied
     to   a  narrative  water  quality  standard
     provision that prohibits toxicity in receiving
     waters. Such a procedure is to be used by
     the  State in calculating  derived  numeric
     criteria, which shall be used  for all purposes
     under section 303(c) of the CWA.   At  a
     minimum, such criteria need  to be developed
     for   section  307(a)  toxic  pollutants,  as
     necessary to support designated uses, where
     these pollutants are discharged or present in
     the affected waters and could reasonably be
     expected  to interfere with designated uses.

Option  1  is consistent with State  authority to
establish water quality  standards.  Option  2 most
directly reflects the CWA requirements and is the
option recommended by  EPA.  Option 3, while
meeting the requirements  of the CWA,  is best
suited to supplement numeric criteria from option
1 or 2.  The three options are discussed in more
detail below.
          OPTION 1

     Adopt statewide numeric criteria in State water
     quality standards for all  section  307(a)  toxic
     pollutants for which EPA has developed criteria
     guidance, regardless of whether the pollutants
     are known to be present.
     Pro:
     •    simple, straightforward implementation

     •    ensures that States will satisfy statute

     •    makes   maximum   uses   of    EPA
          recommendations

     •    gets specific numbers into State water quality
          standards  fast, at first

     Con:

     •    some priority toxic pollutants may not be
          discharged in State

     •    may cause unnecessary monitoring by States

     •    might result in  "paper  standards"

     Option  1 is  within a State's  legal authority under
     the CWA to adopt broad water quality standards.
     This option  is the most comprehensive approach
     to satisfy the statutory  requirements  because it
     would include all of the priority toxic pollutants
     for  which  EPA  has prepared  section  304 (a)
     criteria guidance for either  or both aquatic life
     protection  and  human  health  protection.   In
     addition to  a simple adoption  of EPA's section
     304(a) guidance as standards, a State must select
     a risk level for those  toxic  pollutants which  are
     carcinogens (i.e., that cause or may cause cancer
     in humans).

     Many States find this option attractive because it
     ensures comprehensive coverage of the priority
     toxic  pollutants with  scientifically  defensible
     criteria without the  need to conduct a resource-
     intensive evaluation of the particular segments and
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                                                                    Chapter 3 - Water Quality Criteria
pollutants requiring criteria.   This  option  also
would not be more costly to  dischargers  than
other options  because permit  limits would be
based  only  on the  regulation of  the particular
toxic pollutants in their discharges and not on the
total listing in the water quality standards.  Thus,
actual permit limits should be the same under any
of the options.

The State may also exercise its authority  to use
one or more of the techniques for adjusting water
quality standards:

•    establish or  revise designated stream  uses
     based  on  use  attainability   analyses  (see
     section 2.9);

•    develop site-specific criteria; or

•    allow short-term  variances (see  section  5.3)
     when appropriate.

All  three  of  these  techniques may  apply to
standards developed  under  any  of the three
options discussed in this guidance.  It  is likely
that States electing to use option 1 will rely more
on  variances because  the  other two  options are
implemented with more site-specific data being
available.   It  should  be  noted,  however,  that
permits  issued pursuant  to  such  water quality
variances still  must comply with  any applicable
antidegradation and antibacksliding requirements.

     OPTION!

Adopt specific numeric criteria in State water
quality  standards  for  section  307(a)  toxic
pollutants as necessary to support designated
uses where such pollutants are discharged or
are present  in the affected  waters and could
reasonably   be  expected to  interfere  with
designated uses.
Pro:
     directly reflects statutory requirement
•    standards based  on demonstrated  need  to
     control problem pollutants

•    State can use EPA's section 304(a) national
     criteria   recommendations   or   other
     scientifically acceptable alternative, including
     site-specific criteria

•    State can consider current or potential toxic
     pollutant problems

•    State can go beyond  section 307(a) toxics
     list,  as desired

Con:

•    may be  difficult and  time consuming  to
     determine  if,  and  which,  pollutants are
     interfering with the designated use

•    adoption of standards can  require  lengthy
     debates  on  correct  criteria limit  to  be
     included in standards

•    successful State toxic control programs based
     on narrative criteria may be halted or slowed
     as the State applies its limited resources  to
     developing numeric standards

•    difficult  to update criteria once adopted  as
     part  of standards

•    to be absolutely technically defensible, may
     need site-specific criteria in many situations,
     leading to a large workload for regulatory
     agency

EPA recommends that a State  use this option  to
meet the statutory requirement.  It directly reflects
all   the  Act's  requirements  and  is  flexible,
resulting  in adoption  of  numeric water quality
standards  as needed.  To assure that the State  is
capable of dealing  with new  problems as they
arise, EPA  also recommends that States adopt a
translator procedure the same  as, or similar to,
that  described in option 3,  but applicable to all
chemicals causing toxicity  and not just priority
pollutants as is the case for  option 3.
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Beginning in  1988,  EPA provided  States with
candidate  lists of priority toxic  pollutants  and
water bodies in support of CWA section 304(1)
implementation.   These  lists  were  developed
because States were required to evaluate existing
and readily available water-related data to comply
with section  304(1), 40 CFR 130.10(d).  A similar
"strawman"   analysis   of  priority  pollutants
potentially requiring adoption of numeric criteria
under section 303(c)(2)(B) was furnished to most
States in September or October of 1990 for their
use in ongoing and subsequent triennial reviews.
The primary differences between the  "strawman"
analysis and  the section 304(1) candidate lists were
that the "strawman" analysis  (1) organized the
results by  chemical rather than by water body, (2)
included data for certain STORET monitoring
stations  that were not used in constructing the
candidate  lists, (3) included data from the Toxics
Release  Inventory database,  and  (4)  did  not
include  a number  of data  sources   used  in
preparing  the candidate lists (e.g., those, such as
fish kill  information, that  did not  provide
chemical-specific information).

EPA intends for States, at a minimum, to use the
information  gathered in support of section 304(1)
requirements as a starting point for identifying (1)
water segments that will need new and/or revised
water quality  standards for section  307(a) toxic
pollutants, and (2) which priority toxic pollutants
require  adoption  of numeric  criteria.   In the
longer term, EPA expects similar determinations
to occur during each  triennial review of water
quality standards as required by section 303(c).

In identifying the need for numeric criteria, EPA
is encouraging States to use information and data
such as:

•    presence   or  potential   construction   of
     facilities that manufacture or  use priority
     toxic pollutants;

•    ambient  water  monitoring data,  including
     those for sediment and aquatic life (e.g., fish
     tissue data);
•    NPDES permit applications and  permittee
     self-monitoring reports;

•    effluent guideline development documents,
     many of which  contain section  307(a)(l)
     priority pollutant scans;

•    pesticide   and   herbicide   application
     information and other records of pesticide or
     herbicide inventories;

•    public water supply source monitoring data
     noting   pollutants    with   Maximum
     Contaminant Levels (MCLs); and

•    any  other  relevant information  on  toxic
     pollutants   collected  by  Federal,  State,
     interstate agencies, academic  groups,  or
     scientific organizations.

States  are also  expected to take  into account
newer information as it became available, such as
information  in  annual reports  from  the Toxic
Chemical  Release Inventory requirements of  the
Emergency Planning and Community  Right-To-
Know Act of 1986 (Title III, Public Law 99-499).

Where the State's review indicates a reasonable
expectation of a problem from the discharge or
presence  of  toxic  pollutants, the  State  should
identify   the  pollutant(s)   and   the   relevant
segment(s).   In  making these determinations,
States should use their own EPA-approved criteria
or  existing  EPA  water  quality  criteria  for
purposes  of  segment identification.   After  the
review, the State may use other means to establish
the final criterion as it revises its standards.

As with option  1,  a State using option 2 must
follow  all   its   legal   and  administrative
requirements  for  adoption  of  water  quality
standards. Since the resulting numeric criteria are
part of a State's water quality standards, they  are
required to be submitted by the State to EPA for
review and either approval  or disapproval.

EPA believes this option offers the State optimum
flexibility.  For  section 307(a) toxic  pollutants
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                                                                   Chapter 3 - Water Quality Criteria
 adversely  affecting  designated  uses,  numeric
 criteria are available for permitting purposes. For
 other  situations,  the  State  has the option  of
 defining site-specific criteria.

     OPTION 3

 Adopt  a  procedure  to  be  applied  to the
 narrative water quality standard provision that
 prohibits toxicity in receiving waters.  Such a
 procedure  would  be  used  by  a  State  in
 calculating derived numeric criteria to be used
 for all purposes of water quality criteria under
 section 303 (c) of the CWA.   At a minimum
 such criteria need to be  derived for section
 307(a) toxic pollutants where the  discharge  or
 presence of  such  pollutants in  the  affected
 waters  could  reasonably  be  expected   to
 interfere with designated uses, as necessary  to
 support such designated uses.
Pro:
     allows a State flexibility to control priority
     toxic pollutants

     reduces time  and cost required to adopt
     specific numeric criteria  as  water quality
     standards regulations

     allows immediate use  of latest scientific
     information  available at the time  a  State
     needs to develop derived numeric criteria

     revisions and additions  to derived numeric
     criteria can be made without need to revise
     State law

     State can deal more  easily with  a situation
     where  it did  not establish  water quality
     standards  for  the  section  307(a)  toxic
     pollutants during the most recent triennial
     review

     State can address problems from non-section
     307(a) toxic pollutants
 Con:

 •    EPA  is currently on notice that a derived
     numeric criterion may invite legal challenge

 •    once the necessary procedures are adopted to
     enhance legal defensibility (e.g., appropriate
     scientific  methods and public participation
     and review), actual savings in time and costs
     may be less than expected

 •    public  participation  in  development   of
     derived numeric criteria may  be limited
     when such criteria  are  not addressed in a
     hearing on water quality standards

 EPA believes that adoption of a narrative standard
 along with a translator mechanism as part of a
 State's  water   quality  standard   satisfies   the
 substantive requirements  of the statute.  These
 criteria are subject to all the  State's legal and
 administrative  requirements   for   adoption   of
 standards  plus  review  and either approval  or
 disapproval  by  EPA,   and   result  in   the
 development of derived  numeric criteria  for
 specific section 307(a) toxic pollutants. They are
 also  subject  to  an  opportunity  for  public
 participation.   Nevertheless,  EPA believes the
 most appropriate  use  of option 3 is as  a
 supplement to either option 1 or 2.  Thus, a State
 would have formally adopted numeric criteria for
 toxic pollutants that occur frequently; that have
 general applicability statewide for inclusion  in
 NPDES permits, total maximum daily loads, and
 waste load allocations; and that also would have
 a  sound  and  predictable method  to  develop
 additional  numeric criteria as  needed.   This
 combination  of options  provides a complete
 regulatory scheme.

 Although the approach in option 3 is similar  to
 that  currently  allowed  in the Water Quality
 Standards Regulation (40 CFR 131.11(a)(2)), this
guidance  discusses several administrative  and
scientific  requirements  that  EPA believes  are
necessary to comply with section 303(c)(2)(B).
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(1)   The Option 3 Procedure Must Be Used To
     Calculate Derived Numeric Water Quality
     Criteria

States  must adopt  a specific  procedure to be
applied to a narrative water quality criterion.  To
satisfy section 303(c)(2)(B), this procedure shall
be  used by  the  State  in  calculating  derived
numeric  criteria, which  shall be  used for all
purposes under section 303(c) of the CWA.  Such
criteria need to be developed for section 307(a)
toxic pollutants as necessary to support designated
uses, where these pollutants are discharged or are
present  in the   affected  waters  and   could
reasonably be  expected  to  interfere  with  the
designated  uses.

To  assure protection from short-term exposures,
the State procedure should ensure development of
derived numeric water quality criteria  based on
valid acute aquatic toxicity tests that are lethal to
half the affected organisms (LC50) for the species
representative of or similar to those found in the
State.  In  addition,  the  State  procedure should
ensure development of  derived  numeric  water
quality  criteria  for  protection  from  chronic
exposure by  using  an appropriate  safety factor
applicable  to  this  acute limit.    If  there  are
saltwater  components  to the State's aquatic
resources,  the State  should establish appropriate
derived numeric criteria for saltwater in addition
to those for freshwater.

The State's documentation  of the  tests should
include a detailed discussion of its quality control
and quality assurance procedures.   The  State
should also include  a description (or  reference
existing technical agreements with EPA) of the
procedure  it will use to calculate derived  acute
and chronic numeric criteria from  the  test data,
and how these derived criteria will be used as the
basis for deriving appropriate TMDLs, WLAs,
and NPDES permit limits.

As  discussed above, the procedure for calculating
derived numeric criteria  needs to protect aquatic
life from  both acute and chronic  exposure to
specific chemicals.   Chronic aquatic life criteria
are to be met at the edge of the mixing zone.
The acute criteria are to be met (1) at the end-of-
pipe if mixing is not rapid and complete and  a
high  rate diffuser  is not  present;  or  (2) after
mixing if mixing is rapid and complete or a high
rate diffuser is present. (See EPA's Technical
Support Document for Water Quality-based Toxics
Control,  USEPA  199la.)

EPA   has  not  established  a  national  policy
specifying the point of application in the receiving
water  to  be used  with human  health criteria.
However, EPA has approved State standards that
apply human health criteria for fish consumption
at the mixing zone boundary and/or apply  the
criteria for drinking water  consumption, at  a
minimum,  at the point of use.   EPA has also
proposed  more  stringent requirements  for  the
application of human health criteria for highly
bioaccumulative pollutants in the Water Quality
guidance for the Great Lakes  System (50 F.R.
20931,  21035,  April   16,   1993)  including
elimination of mixing zones.

In  addition,  the  State  should also  include an
indication  of  potential   bioconcentration  or
bioaccumulation by providing for:

•    laboratory tests that measure the steady-state
     bioconcentration   rate   achieved   by   a
     susceptible organism;  and/or

•    field data  in  which ambient concentrations
     and tissue loads are  measured  to give an
     appropriate factor.

In  developing   a  procedure  to  be  used  in
calculating  derived numeric  criteria  for  the
protection  of  aquatic  life,  the  State  should
consider the potential impact that bioconcentration
has on aquatic and terrestrial food chains.

The   State  should  also   use   the   derived
bioconcentration  factor to calculate  chronically
protective  numeric criteria  for  humans that
consume aquatic  organisms.   In calculating this
derived  numeric  criterion,   the  State  should
indicate data requirements to be met when  dealing
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                                                                   Chapter 3 - Water Quality Criteria
with  either  threshold  (toxic)  or  nonthreshold
(carcinogenic)  compounds.   The  State  should
describe the species and the minimum number of
tests, which  may generally be  met by a  single
mammalian chronic test if it  is of good quality
and if the weight of evidence indicates that the
results are reasonable.  The State should provide
the  method  to  calculate  a  derived  numeric
criterion from the appropriate test result.

Both the threshold and nonthreshold  criteria for
protecting human health should  contain exposure
assumptions, and the State procedure should  be
used  to  calculate derived numeric criteria that
address the consumption of water, consumption of
fish,  and combined consumption of  both  water
and  fish.    The State  should  provide  the
assumptions regarding the amount of fish and the
quantity  of water consumed per person per day,
as  well   as  the  rationale used to  select  the
assumptions.  It  needs  to include the number of
tests, the species necessary to establish a dose-
response  relationship, and the  procedure  to  be
used  to  calculate the derived numeric criteria.
For nonthreshold contaminants,  the State should
specify the model used to extrapolate to low dose
and the  risk  level.    It  should also  address
incidental  exposure from other water sources
(e.g.,  swimming).   When calculating  derived
numeric   criteria  for  multiple  exposure  to
pollutants, the  State  should  consider additive
effects, especially  for  carcinogenic  substances,
and should factor in the contribution to the daily
intake of toxicants from other sources (e.g., food,
air) when data are available.
(2)  The State  Must  Demonstrate  That the
     Procedure  Results  in  Derived Numeric
     Criteria Are Protective
     The State needs  to demonstrate  that  its
     procedures for developing criteria, including
     translator methods,  yield fully protective
     criteria for human health and for aquatic
     life.   EPA's review process will  proceed
     according to EPA's regulation of 40 CFR
     131.11, which requires that criteria be based
     on   sound  scientific  rationale   and   be
     protective of all designated uses.  EPA will
     use  the  expertise  and  experience  it  has
     gained in developing  section  304(a) criteria
     for toxic pollutants by application of its own
     translator method (USEPA, 1980b; USEPA,
     1985b).

Once EPA  has approved the State's procedure,
the Agency's review of derived numeric  criteria,
for example,  for pollutants other than section
307(a) toxic pollutants resulting from the State's
procedure, will focus on the adequacy of the data
base rather than the calculation method.  EPA
also encourages States to apply such a procedure
to calculate derived numeric criteria to be used as
the basis  for deriving  permit limitations  for
nonconventional  pollutants   that   also  cause
toxicity.

(3)  The State Must Provide Full Opportunity
     for Public Participation in Adoption of the
     Procedure

The Water Quality Standards Regulation requires
States to hold public hearings to review and revise
water  quality  standards  in   accordance with
provisions  of State  law  and  EPA's  Public
Participation Regulation (40 CFR 25).  Where a
State plans to  adopt a procedure to be applied to
the narrative   criterion,  it  must  provide   full
opportunity  for public   participation   in   the
development and adoption of the procedure as part
of the State's water quality standards.

While it is  not necessary for the  State  to adopt
each derived  numeric  criterion into its water
quality standards and submit it to EPA for review
and approval,  EPA  is  very concerned  that all
affected  parties have adequate opportunity  to
participate  in  the  development  of  a  derived
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numeric  criterion  even though it is  not being
adopted directly as a water quality standard.

A State  can  satisfy the need  to provide  an
opportunity  for  public  participation  in  the
development of derived numeric criteria in several
ways, including:

•    a specific hearing on the derived numeric
     criterion;

•    the  opportunity for a public hearing on  an
     NPDES permits as long as public notice is
     given that a criterion  for a toxic pollutant as
     part of  the  permit  issuance  is  being
     contemplated; or

•    a hearing coincidental with any other hearing
     as long as it is made  clear that development
     of  a   specific  criterion is  also  being
     undertaken.

For  example,  as States develop  their lists and
individual control strategies (ICSs) under section
304(1), they may seek full public participation.
NPDES   regulations   also  specify   public
participation requirements  related  to State permit
issuance. Finally, States have public participation
requirements   associated  with Water  Quality
Management  Plan  updates.   States  may  take
advantage of  any of these  public  participation
requirements to fulfill the  requirement for public
review of any  resulting derived numeric criteria.
In such cases, the State must give prior notice that
development   of    such   criteria    is   under
consideration.

(4)  The Procedure Must Be Formally Adopted
     and Mandatory

Where a State elects to supplement its narrative
criterion  with  an accompanying  implementing
procedure,  it  must formally  adopt  such   a
procedure as a part of its water quality standards.
The  procedure must be  used by  the State  to
calculate derived numeric criteria mat will be used
as the basis for all standards' purposes, including
the following: developing TMDLs, WLAs, and
limits in NPDES permits;  determining whether
water  use  designations are  being  met;  and
identifying potential nonpoint  source  pollution
problems.

(5)  The Procedure Must Be Approved by EPA
     as Part  of the  State's  Water  Quality
     Standards Regulation

To be consistent with the requirements of the Act,
the State's procedure to be applied to the narrative
criterion must be submitted to  EPA for review
and  approval, and  will become a part of the
State's water quality standards.  (See 40 CFR
131.21 for further discussion.) This requirement
may be satisfied by a reference in the standards to
the procedure, which may be contained in another
document, which has legal  effect and is binding
on the State, and all the requirements for public
review, State implementation, and  EPA review
and approval are satisfied.

     Criteria Based on Biological Monitoring

For priority toxic pollutants for which EPA has
not issued section  304(a)(l) criteria guidance,
CWA section 303(c)(2)(B) requires States to adopt
criteria based   on  biological   monitoring  or
assessment  methods.    The  phrase "biological
monitoring or assessment methods" includes:

•    whole-effluent toxicity control methods;

•    biological criteria  methods; or

•    other   methods   based   on   biological
     monitoring or assessment.

The phrase "biological  monitoring or assessment
methods"  in its  broadest  sense  also  includes
criteria developed through translator procedures.
This  broad  interpretation   of   that  phrase is
consistent  with  EPA's  policy  of  applying
chemical-specific, biological, and whole-effluent
toxicity methods independently in  an integrated
toxics control program. It is also consistent with
the intent of Congress  to expand State standards
programs beyond chemical-specific approaches.
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                                                                  Chapter 3 - Water Quality Criteria
States should also consider developing protocols
to derive and adopt numeric criteria for priority
toxic pollutants (or other pollutants) where EPA
has not issued  section 304(a) criteria guidance.
The State  should consider  available laboratory
toxicity (bioassay) data that may be sufficient to
support derivation of chemical-specific criteria.
Existing data need not be as  comprehensive as
that required to meet EPA's 1985  guidelines in
order for a State to use its own protocols to derive
criteria. EPA has described such protocols in the
proposed Water Quality Guidance for the Great
Lakes System (58 F.R. 20892, at 21016, April 16,
1993.)  This is particularly important where other
components  of  a  State's narrative  criterion
implementation procedure (e.g., WET controls or
biological criteria) may not ensure full protection
of  designated  uses.    For  some  pollutants,  a
combination  of   chemical-specific  and  other
approaches is necessary  (e.g., pollutants where
bioaccumulation   in   fish   tissue  or   water
consumption by humans is a primary concern).

Biologically  based  monitoring or assessment
methods serve as the basis for control  where no
specific numeric criteria exist or where calculation
or  application  of pollutant-by-pollutant criteria
appears infeasible.  Also,  these methods may
serve   as  a   supplemental  measurement  of
attainment  of water quality standards in addition
to  numeric   and  narrative   criteria.    The
requirement  for  both  numeric   criteria  and
biologically based methods demonstrates  that
section  303(c)(2)(B)  contemplates  that  States
develop a comprehensive toxics control program
regardless of the status of EPA's section 304(a)
criteria.

The  whole-effluent  toxicity  (WET)  testing
procedure is the principal biological monitoring
guidance developed by EPA to date. The purpose
of the WET procedure is to control point source
dischargers of toxic pollutants.  The procedure is
particularly useful for monitoring and controlling
the toxicity of complex effluents that may not be
well controlled through chemical-specific numeric
criteria.   As such,  biologically based effluent
testing  procedures are a necessary component of
a  State's toxics control  program  under section
303(c)(2)(B)  and   a   principal   means  for
implementing a  State's  narrative  "free  from
toxics" standard.

Guidance documents EPA considers to serve the
purpose of section 304(a)(8) include the Technical
Support Document for Water Quality-based Toxics
Control (USEPA, 199 la; Guidelines for Deriving
National Water Quality Criteria for the Protection
of Aquatic Organisms and Their Uses (Appendix
H);  Guidelines  and Methodology Used in the
Preparation of Health Effect Assessment Chapters
of the Consent Decree Water Criteria Documents
(Appendix  J); Methods for Measuring  Acute
Toxicity  of Effluents to Freshwater and Marine
Organisms (USEPA, 1991d); Short-Term Methods
for Estimating the Chronic Toxicity of Effluents
and Receiving Waters to Freshwater Organisms
(USEPA, 1991e); and Short-Term Methods for
Estimating the Chronic Toxicity of Effluents and
Receiving  Waters  to Marine  and   Estuarine
Organisms (USEPA, 1991f).

3.4.2  Criteria for Nonconventional Pollutants

Criteria requirements applicable to toxicants that
are not priority toxic pollutants (e.g., ammonia
and  chlorine), are specified  in  the 1983  Water
Quality  Standards   Regulation  (see  40  CFR
131.11).  Under these requirements,  States must
adopt criteria based on sound scientific rationale
that  cover  sufficient  parameters  to  protect
designated uses.   Both  numeric  and narrative
criteria (discussed in sections  3.5.1 and  3.5.2,
below)   may  be   applied   to  meet   these
requirements.
       Forms of Criteria
States are required to adopt water quality criteria,
based on  sound scientific rationale, that contain
sufficient parameters or constituents to protect the
designated use.  EPA believes that an effective
State water  quality standards program should
include both  parameter-specific (e.g.,  ambient
numeric criteria) and narrative approaches.
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3.5.1  Numeric Criteria

Numeric criteria are required where necessary to
protect  designated  uses.   Numeric  criteria  to
protect aquatic life should be developed to address
both short-term  (acute) and long-term (chronic)
effects.  Saltwater species, as  well as freshwater
species, must be adequately protected.  Adoption
of numeric criteria is  particularly important for
toxicants known to be impairing surface waters
and  for  toxicants with potential human health
impacts (e.g., those with  high  bioaccumulation
potential).   Human health should be protected
from exposure resulting  from  consumption  of
water and fish or other aquatic  life (e.g., mussels,
crayfish).  Numeric water quality criteria also are
useful in  addressing nonpoint source pollution
problems.

In evaluating whether  chemical-specific numeric
criteria  for toxicants that are not priority toxic
pollutants are required,  States  should  consider
whether other approaches (such as whole-effluent
toxicity criteria or biological controls) will ensure
full protection of designated uses.  As mentioned
above, a combination of independent approaches
may be required in some cases to  support the
designated uses and comply with the requirements
of the Water Quality Standards Regulation (e.g.,
pollutants where bioaccumulation in fish tissue or
water  consumption by  humans is  a  primary
concern).

3.5.2  Narrative Criteria

To supplement numeric criteria for toxicants,  all
States have also adopted  narrative  criteria for
toxicants.  Such narrative criteria are statements
that describe the desired water quality goal, such
as the following:

     All waters,   including   those  within
     mixing  zones,  shall  be  free from
     substances  attributable to  wastewater
     discharges  or other pollutant sources
     that:
     (1)   Settle   to   form   objectional
          deposits;

     (2)   Float  as  debris,  scum,  oil,  or
          other matter forming nuisances;

     (3)   Produce objectionable color, odor,
          taste, or turbidity;

     (4)   Cause injury to, or are toxic to,
          or produce adverse physiological
          responses in humans, animals, or
          plants; or

     (5)   Produce undesirable or nuisance
          aquatic life (54 F.R. 28627, July
          6, 1989).

EPA considers that the narrative criteria apply to
all designated uses at all flows and are necessary
to meet  the  statutory  requirements  of section
303(c)(2)(A) of the CWA.

Narrative toxic criteria (No. 4, above) can be the
basis for establishing chemical-specific limits for
waste discharges where a specific pollutant can be
identified as causing or contributing to the toxicity
and the State has not  adopted chemical-specific
numeric criteria. Narrative toxic criteria are cited
as a basis for establishing whole-effluent toxicity
controls in EPA permitting regulations at 40 CFR
122.44(d)(l)(v).

To ensure that narrative criteria for toxicants are
attained,  the Water Quality Standards Regulation
requires   States   to  develop   implementation
procedures (see 40  CFR  131.11(a)(2)).   Such
implementation procedures (Exhibit 3-3)  should
address all mechanisms to be used by the State to
ensure  that   narrative  criteria   are  attained.
Because   implementation  of  chemical-specific
numeric  criteria  is  a key  component of State
toxics   control   programs,   narrative  criteria
implementation  procedures  must  describe  or
reference the  State's  procedures to implement
such  chemical-specific  numeric criteria  (e.g.,
procedures  for  establishing  chemical-specific
permit  limits  under   the  NPDES  permitting
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                                                                   Chapter 3 - Water Quality Criteria
program).  Implementation procedures must also
    State implementation procedures for narrative toxics criteria should describe the following:

    •    Specific, scientifically defensible methods by which the State will implement its narrative
         toxics standard for all toxicants,  including:

         -  methods for chemical-specific criteria, including methods for applying chemical-specific
           criteria in permits, developing or modifying chemical-specific criteria via a "translator
           procedure" (defined and discussed below), and calculating site-specific criteria based
           on local water chemistry or biology);

         -  methods for developing and  implementing  whole-effluent  toxicity criteria and/or
           controls; and

         -  methods for developing and implementing biological criteria.

    *    How these methods will be integrated in the State's toxics control program (i.e., how the
         State will proceed when the specified methods produce conflicting or inconsistent results).

    •    Application criteria and  information needed to apply numerical criteria, for example:

         -  methods the State will  use to identify those  pollutants to be regulated in a specific
           discharge;

         -  an incremental cancer risk  level for carcinogens;

         -  methods for identifying compliance thresholds in permits where calculated limits are
           below detection;

         -  methods for selecting  appropriate hardness, pH, and temperature variables for criteria
           expressed as functions;

         -  methods or policies controlling the size and in-zone quality of mixing zones;

         -  design flows to be used in translating chemical-specific numeric criteria for aquatic life
           and human health into permit limits; and

         -  other methods and information needed to apply standards on a case-by-case basis.

  Exhibit 3-3.   Components of a State Implementation Procedure for Narrative Toxics Criteria
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Water Quality Standards Handbook - Second Edition
program).  Implementation procedures must also
address State programs to control whole-effluent
toxicity (WET)  and may  address programs to
implement   biological  criteria,   where   such
programs  have  been developed  by the  State.
Implementation  procedures therefore  serve  as
umbrella documents that describe how the State's
various toxics control programs are integrated to
ensure adequate protection for aquatic  life and
human  health and  attainment of the  narrative
toxics criterion.  In essence, the procedure should
apply  the  "independent  application" principle,
which  provides  for  independent  evaluations of
attainment of a designated use based on chemical-
specific, whole-effluent toxicity,  and biological
criteria  methods  (see   section  3.5.3   and
Appendices C, K, and R).

EPA  encourages, and may  ultimately  require,
State  implementation procedures  to provide for
implementation of biological criteria.  However,
the regulatory basis for requiring whole-effluent
toxicity (WET) controls is clear. EPA regulations
at  40  CFR  122.44(d)(l)(v) require  NPDES
permits to contain WET limits where a permittee
has been shown  to cause, have  the reasonable
potential to cause, or contribute to an in-stream
excursion of a narrative criterion. Implementation
of chemical-specific controls  is also required by
EPA regulations at 40 CFR 122.44(d)(l).  State
implementation procedures should, at a minimum,
specify or reference methods to  be  used  in
implementing chemical-specific and whole-effluent
toxicity-based  controls,   explain  how   these
methods are  integrated,   and specify  needed
application criteria.

In addition to EPA's regulation at 40 CFR 131,
EPA has regulations at 40 CFR 122.44 that cover
the  National Surface  Water  Toxics  Control
Program.    These regulations are intrinsically
linked  to  the  requirements  to  achieve  water
quality standards, and  specifically address the
control of  pollutants  both  with and  without
numeric  criteria.     For  example,   section
122.44(d)(l)(vi) provides the permitting authority
with several options for establishing effluent limits
when a State does not have  a chemical-specific
numeric criterion for a pollutant present in an
effluent  at   a  concentration  that  causes  or
contributes to a violation of the State's narrative
criteria.

3.5.3  Biological Criteria

The  Clean Water Act of 1972  directs EPA to
develop programs that will evaluate, restore, and
maintain the chemical, physical, and biological
integrity of the Nation's waters.  In response to
this directive, States and EPA have implemented
chemically based water  quality  programs  that
address significant  water pollution  problems.
However, over the past 20 years, it has become
apparent that these programs alone cannot identify
and address all surface water pollution problems.
To help create a more comprehensive program,
EPA is setting a priority  for the development of
biological criteria as part of State water quality
standards.  This effort will help States and EPA
(1) achieve the biological integrity objective of the
CWA  set forth in section  101,  and (2) comply
with the statutory requirements under sections 303
and 304 of the Act (see Appendices C and K).

     Regulatory Bases for Biocriteria

The primary statutory basis for EPA's policy that
States  should develop biocriteria  is  found in
sections  101(a)  and 303(c)(2)(B)  of the Clean
Water  Act.  Section 101 (a) of the CWA gives the
general goal of biological criteria.  It establishes
as the  objective of the Act the restoration and
maintenance  of  the  chemical,  physical,  and
biological integrity of the Nation's waters.  To
meet this objective, water quality criteria should
address biological  integrity.    Section 101 (a)
includes the  interim water quality  goal for the
protection and propagation of fish, shellfish, and
wildlife.

Section 304(a) of the Act provides the legal basis
for the development of  informational criteria,
including biological criteria.  Specific directives
for the development of regulatory biocriteria can
be found in section 303(c), which requires EPA to
develop criteria based on biological  assessment
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                                                                     Chapter 3 - Water Quality Criteria
 methods   when  numerical   criteria  are   not
 established.

 Section 304(a) directs EPA to develop and publish
 water quality criteria and information on methods
 for measuring water quality and establishing water
 quality criteria for toxic pollutants on bases other
 than  pollutant-by-pollutant,  including biological
 monitoring and  assessment methods that assess:

 •    the   effects   of   pollutants  on   aquatic
      community components  (".  .  .  plankton,
      fish, shellfish,  wildlife, plant life . . .") and
      community  attributes  (".   .  .  biological
      community  diversity,   productivity,  and
      stability . . .") in any body of water; and

 •    factors  necessary   "...  to  restore and
      maintain   the   chemical,   physical,  and
      biological integrity of all  navigable waters .
      .." for "... the protection of shellfish,
      fish, and wildlife for classes and categories
      of receiving waters . . . ."

 Once biocriteria are formally  adopted into State
 standards,   biocriteria   and   aquatic  life  use
 designations  serve as direct, legal endpoints  for
 determining  aquatic  life  use  attainment/non-
 attainment.   CWA section 303(c)(2)(B) provides
 that  when numeric  criteria are not available,
 States shall  adopt criteria  for toxics based  on
 biological  monitoring  or assessment  methods;
 biocriteria can be used to meet this requirement.

     Development   and  Implementation  of
     Biocriteria

 Biocriteria are  numerical  values or  narrative
 expressions that describe the expected reference
 biological  integrity of aquatic  communities
 inhabiting waters of a designated aquatic life use.
 In the most  desirable scenario,  these would be
 waters that are  either  in pristine condition  or
 minimally  impaired.  However,  in some areas
 these  conditions no  longer exist and may not be
attainable.    In  these situations, the reference
biological  communities  represent   the  best
attainable conditions. In either case, the reference
 conditions then become the basis for developing
 biocriteria for major surface water types (streams,
 rivers,  lakes,   wetlands,  estuaries,  or  marine
 waters).

 Biological criteria support designated aquatic life
 use   classifications   for  application  in  State
 standards (see chapter 2). Each State develops its
 own designated use classification system based on
 the generic uses cited in the Act (e.g., protection
 and propagation of fish, shellfish, and wildlife).
 Designated  uses  are   intentionally   general.
 However,  States  may  develop  subcategories
 within use designations  to refine and clarify the
 use  class.   Clarification of  the use  class  is
 particularly helpful when a variety of  surface
 waters with distinct characteristics fit within the
 same use  class, or  do  not  fit  well  into  any
 category.

 For example, subcategories of aquatic life uses
 may be on the basis of attainable habitat (e.g.,
 coldwater  versus warmwater stream systems as
 represented by distinctive trout  or bass  fish
 communities,  respectively).   Special uses may
 also be designated to protect particularly unique,
 sensitive,   or  valuable  aquatic   species,
 communities, or habitats.

 Resident biota  integrate multiple impacts over
 time and can detect impairment from known and
 unknown causes. Biological criteria can be used
 to  verify  improvement in  water  quality  in
 response to regulatory  and other improvement
 efforts  and   to  detect  new  or  continuing
 degradation of waters.   Biological criteria also
 provide a  framework for developing improved
 best   management  practices  and management
 measures for nonpoint source impacts.  Numeric
biological   criteria   can  provide   effective
 monitoring criteria for more definitive evaluation
of the health of an aquatic ecosystem.

The assessment of the biological integrity of a
water  body  should  include  measures   of  the
structure and function of the aquatic community
within a specified habitat.  Expert knowledge of
the system is  required for   the selection  of
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appropriate   biological   components   and
measurement  indices.    The  development  and
implementation of biological criteria requires:

•    selection   of  surface  waters  to   use in
     developing reference conditions  for each
     designated use;

•    measurement of the structure and function of
     aquatic communities  in  reference  surface
     waters to establish biological criteria;

•    measurement of  the  physical  habitat  and
     other  environmental characteristics of  the
     water resource; and

•    establishment of a protocol to compare the
     biological criteria to biota in comparable test
     waters to determine whether impairment has
     occurred.

These elements serve  as an interactive network
that  is  particularly   important   during early
development of biological criteria where rapid
accumulation  of information  is  effective   for
refining  both  designated uses and developing
biological  criteria  values and  the supporting
biological monitoring and assessment techniques.

3.5.4  Sediment Criteria

While ambient water quality criteria are playing
an important role in assuring a healthy aquatic
environment, they alone have not been sufficient
to ensure  appropriate levels  of  environmental
protection.  Sediment  contamination, which can
involve deposition of toxicants over long periods
of time, is responsible for water quality impacts
in some areas.

EPA has authority to pursue the development of
sediment  criteria in  streams,  lakes and other
waters of the United States under sections 104 and
304(a)(l) and  (2) of the CWA as follows:

•    section   104(n)(l)   authorizes   the
     Administrator to establish national programs
     that study the effects of pollution, including
     sedimentation, in estuaries on aquatic life;

•    section 304(a)(l) directs the Administrator to
     develop  and  publish  criteria  for  water
     quality, including information on the factors
     affecting  rates of  organic  and  inorganic
     sedimentation for varying types of receiving
     waters;

•    section 304(a)(2) directs the Administrator to
     develop and publish information  on, among
     other issues,  "the factors necessary for the
     protection and propagation of shellfish, fish,
     and wildlife for classes  and  categories of
     receiving waters. ..."

To  the extent  that  sediment  criteria could be
developed that address the concerns of the section
404(b)(l) Guidelines for discharges of dredged or
fill  material  under the  CWA  or the  Marine
Protection, Research, and Sanctuaries Act,  they
could also be incorporated into those regulations.

EPA's  current  sediment  criteria  development
effort, as described below, focuses on  criteria for
the  protection of aquatic life.  EPA  anticipates
potential future expansion of this effort to include
sediment criteria  for the  protection  of human
health.

     Chemical  Approach to Sediment Criteria
     Development

Over the past  several  years,  sediment criteria
development activities have centered on evaluating
and   developing   the  Equilibrium  Partitioning
Approach for generating sediment criteria.  The
Equilibrium Partitioning  Approach focuses on
predicting  the  chemical  interaction  between
sediments  and  contaminants.   Developing an
understanding  of  the   principal  factors  that
influence  the sediment/contaminant interactions
will  allow predictions to be made regarding the
level  of contaminant concentration that benthic
and other organisms may be exposed to. Chronic
water  quality    criteria,  or   possibly   other
toxicological  endpoints,  can  then be used to
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predict potential biological effects.  In addition to
the development of sediment criteria, EPA is also
working to  develop  a standardized  sediment
toxicity  test  that  could   be  used  with  or
independently  of sediment  criteria to  assess
chronic effects in fresh and marine waters.

     Equilibrium  Partitioning (EqP)  Sediment
     Quality  Criteria  (SQC)  are  the  U.S.
     Environmental Protection Agency's  best
     recommendation of the concentration  of a
     substance  in  sediment  that  will  not
     unacceptably affect benthic  organisms or
     their uses.

Methodologies  for deriving  effects-based  SQC
vary for different classes of compounds.   For
non-ionic organic chemicals, the  methodology
requires normalization  to  organic carbon.   A
methodology for deriving effects-based sediment
criteria   for   metal   contaminants  is   under
development  and  is  expected   to   require
normalization to acid volatile sulfide. EqP SQC
values can  be  derived for  varying degrees of
uncertainty   and   levels  of  protection,   thus
permitting  use  for  ecosystem  protection  and
remedial programs.

     Application of Sediment Criteria

SQC  would  provide  a basis  for  making more
informed decisions on the environmental impacts
of  contaminated  sediments.   Existing sediment
assessment  methodologies  are limited  in their
ability  to   identify   chemicals  of  concern,
responsible parties, degree of contamination, and
zones of impact.  To make the most informed
decisions, EPA believes that a  comprehensive
approach using SQC and biological test methods
is preferred.

Sediment criteria  will be particularly valuable in
site-monitoring  applications  where  sediment
contaminant  concentrations   are  gradually
approaching  a criterion  over  time  or as  a
preventive tool  to ensure that point and nonpoint
sources  of contamination are controlled and  that
uncontaminated sediments remain uncontaminated.
Also  comparison  of  field  measurements  to
sediment criteria will be  a reliable  method for
providing early warning of a potential problem.
An early warning would provide an opportunity to
take corrective  action  before  adverse impacts
occur.   For the reasons mentioned above, it has
been identified that SQC are essential  to resolving
key  contaminated  sediment and  source  control
issues in the Great Lakes.

     Specific Applications

Specific  applications of  sediment   criteria are
under development.   The primary use of EqP-
based sediment  criteria will be to  assess risks
associated with contaminants in sediments. The
various  offices and  programs  concerned  with
contaminated sediment have different regulatory
mandates and,  thus, have  different needs and
areas for potential application of sediment criteria.
Because  each regulatory need is different, EqP-
based   sediment   quality   criteria  designed
specifically to meet the needs  of one office or
program may have to be implemented in different
ways to meet  the  needs  of  another  office  or
program.

One mode of application of EqP-based numerical
sediment quality criteria  would be  in a tiered
approach.    In  such  an    application,  when
contaminants in sediments exceed the sediment
quality criteria the sediments would be considered
as causing unacceptable impacts.  Further testing
may or  may  not be  required depending on site-
specific conditions  and the degree  in which  a
criterion has  been violated.  (In locations where
contamination significantly exceeds a criterion, no
additional testing would  be required.   Where
sediment  contaminant  levels  are   close  to  a
criterion, additional testing might be necessary.)
 Contaminants in a sediment at concentrations less
than the  sediment  criterion would  not  be  of
concern.  However,  in  some cases the sediment
could not be considered  safe because it might
contain other contaminants above safe levels for
which no sediment criteria  exist.  In addition, the
synergistic,  antagonistic,  or additive effects  of
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several contaminants in the sediments may be of
concern.

Additional testing in other tiers of an evaluation
approach, such as bioassays, could be required to
determine if the sediment is safe.  It is likely that
such  testing  would  incorporate   site-specific
considerations. Examples of specific applications
of  sediment  criteria  after they  are developed
include the following:

•    Establish permit limits for point sources to
     ensure that uncontaminated sediments remain
     uncontaminated   or   sediments   already
     contaminated have an opportunity to cleanse
     themselves.   Of  course, this  would occur
     only after criteria and the means to tie point
     sources  to  sediment  contamination   are
     developed.

•    Establish target levels for nonpoint sources
     of sediment contamination.

•    For remediation  activities,  SQC would be
     valuable in identifying:

     -  need  for remediation,

     -  spatial extent of remediation area,

     -  benefits    derived   from   remediation
        activities,

     -  responsible parties,
     -  impacts  of   depositing   contaminated
       sediments in water environments, and

     -  success of remediation activities.

In tiered testing sediment evaluation processes,
sediment criteria and biological testing procedures
work very well together.

     Sediment Criteria Status

     Science Advisory Board Review

The Science Advisory  Board has  completed a
second review of the EqP approach to deriving
sediment    quality   criteria    for   non-ionic
contaminants.    The  November   1992  report
(USEPA,  1992c) endorses the EqP approach to
deriving criteria as ". . .  sufficiently valid to be
used in the  regulatory process if the uncertainty
associated   with the  method  is  considered,
described,  and  incorporated,"   and  that "EPA
should .  .  .  establish  criteria  on the basis of
present  knowledge  within  the   bounds   of
uncertainty. ..."

The Science Advisory Board  also  identified the
need for  ". .  .a better understanding  of the
uncertainty around the assumptions inherent in the
approach, including assumptions of equilibrium,
bioavailability,  and kinetics,  all critical  to  the
application of the EqP."

     Sediment   Criteria   Documents   and
     Application Guidance

EPA  efforts   at  producing  sediment  criteria
documents  are being   directed   first   toward
phenanthrene,   fluoranthene,   dieldrin,
acenaphthene, and endrin. Efforts are also being
directed towards producing a guidance document
on the derivation and interpretation of sediment
quality criteria.   A Federal  Register  Notice
requesting  public  comment  on   the  proposed
methodology  and criteria is expected  in late fall
 1993.  The  draft  guidance  is expected  to be
available  in early spring 1994 for comments.
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                                                                    Chapter 3 - Water Quality Criteria
     Methodology  for  Developing   Sediment
     Criteria for Metal Contaminants

EPA is proceeding to develop a methodology for
calculating sediment criteria for benthic toxicity to
metal  contaminants, with key work focused on
identifying  and understanding the  role of  acid
volatile sulfides (AVS), and other binding factors,
in   controlling  the   bioavailability  of  metal
contaminants.  A variety of field and laboratory
verification  studies  are  under  way  to  add
additional support to the methodology.  Standard
AVS  sampling  and  analytical  procedures  are
under  development.  Presentation of the metals
methodology to the SAB for review is anticipated
for Fall  1993.

     Biological Approach to Sediment Criteria
     Development

Under the Contaminated Sediment  Management
Strategy, EPA programs have committed to using
consistent  biological  methods  to determine  if
sediments  are  contaminated.    In the  water
program, these biological methods will be used as
a complement to the  sediment-chemical criteria
under  development.    The  biological  methods
consist of both toxicity and bioaccumulation tests.
Freshwater and saltwater benthic species, selected
to  represent the  sensitive range  of  species'
responses to toxicity,  are used  in  bioassays to
measure sediment toxicity. Insensitive freshwater
and saltwater benthic species that form the base of
the food chain are  used in bioassays to measure
the bioaccumulation potential of  sediment.  By
December  1993,  acute toxicity  bioassays  and
bioaccumulation tests selected by  all the Agency
programs should be standardized and available for
use.   Training for States and EPA Regions on
these methods is expected to begin in FY1994.

In the next few years, research will be conducted
to develop  standardized chronic toxicity tests for
sediment  as  well  as  toxicity  identification
evaluation (TIE) methods. The TIE approach  will
be used  to identify the specific chemicals  in  a
sediment causing acute or chronic toxicity in the
test  organisms.     Under  the  Contaminated
Sediment Management Strategy, EPA's programs
have  also  agreed to incorporate these chronic
toxicity  and TIE methods into their sediment
testing when they are available.

3.5.5  WUdlife Criteria

Terrestrial   and  avian  species  are  useful  as
sentinels for the health of the ecosystem  as a
whole.   In many  cases,  damage  to  wildlife
indicates that the ecosystem  itself is damaged.
Many wildlife species that are heavily dependent
on  the  aquatic  food web reflect the health of
aquatic  systems.  In the case of toxic chemicals,
terminal predators  such  as  otter,  mink,  gulls,
terns, eagles, ospreys,  and turtles are useful as
integrative  indicators of the status or health of the
ecosystem.

     Statutory and Regulatory Authority

Section  101(a)(2) of the CWA  sets, as an interim
goal of,

     .  .  .  wherever attainable . . .   water
     quality   which   provides   for   the
     protection  and  propagation of fish,
     shellfish, and wildlife .  . . (emphasis
     added).

Section 304(a)(l) of the Act also requires EPA to:

     . .  . develop and publish . .  .  criteria for
     water  quality accurately reflecting ...  the
     kind and extent of all identifiable effects on
     health and welfare including . .  . wildlife.

The Water Quality Standards Regulation reflect
the statutory goals and requirements by requiring
States  to adopt, where  attainable,   the CWA
section  101(a)(2) goal uses  of protection  and
propagation of fish, shellfish, and wildlife  (40
CFR 131.10), and to adopt water quality criteria
sufficient to protect the designated use (40 CFR
131.11).
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     Wildlife  Protection in  Current  Aquatic
     Criteria

Current water  quality  criteria  methodology  is
designed to protect fish, benthic invertebrates, and
zooplankton; however, there is a provision in the
current aquatic  life criteria guidelines (Appendix
H)  that  is intended  to protect  wildlife  that
consume   aquatic    organisms    from   the
bioaccumulative potential of a compound.   The
final residue  value can be based  on either the
FDA  Action  Level or a wildlife feeding study.
However,  if   maximum  permissible  tissue
concentration is not  available from a wildlife
feeding  study,  a final residue value cannot be
derived  and the criteria quantification procedure
continues without further consideration of wildlife
impacts.     Historically,   wildlife  have  been
considered  only  after  detrimental  effects  on
wildlife populations  have been  observed in the
environment (this  occurred  with relationship  to
DDT, selenium, and PCBs).

     Wildlife Criteria Development

EPA's  national wildlife criteria  effort  began
following  release  of  a  1987   Government
Accounting   Office  study   entitled   Wildlife
Management - National Refuge Contamination Is
Difficult To Confirm and Clean Up  (GAO, 1987).
After waterfowl deformities observed at Kesterson
Wildlife   Refuge  were  linked  to   selenium
contamination in the  water, Congress requested
this   study  and   recommended  that   "the
Administrator of EPA, in close coordination with
the Secretary  of  the  Interior,  develop water
quality criteria  for protecting  wildlife and their
refuge habitat."

In November  of  1988,  EPA's Environmental
Research Laboratory in Corvallis sponsored a
workshop  entitled Water  Quality  Criteria  To
Protect  Wildlife Resources,  (USEPA,  1989g)
which was co-chaired by EPA and the  Fish and
Wildlife Service (FWS). The workshop brought
together  26  professionals  from  a variety  of
institutions,  including   EPA,    FWS,   State
governments, academia, and consultants who had
expertise in  wildlife  toxicity,  aquatic  toxicity,
ecology, environmental  risk  assessment,  and
conservation.  Efforts at he workshop focused on
evaluating the need for, and developing a strategy
for  production   of  wildlife  criteria.     Two
recommendations came out of that workshop:
     (1)  The process by
         water   quality
                 which  ambient
                  criteria   are
established should be modified to
consider effects on wildlife; and
     (2)  chemicals  should be  prioritized
         based   on   their  potential   to
         adversely impact wildlife species.
Based   on  the  workshop   recommendations,
screening  level wildlife  criteria  (SLWC)  were
calculated for priority pollutants and chemicals of
concern submitted by the FWS to gauge the extent
of the problem by:

     (1)   evaluating  whether existing  water
          quality  criteria for  aquatic  life  are
          protective of wildlife, and

     (2)   prioritizing chemicals for their potential
          to adversely impact wildlife species.

There were 82 chemicals for  which EPA had the
necessary  toxicity information as well as ambient
water  quality criteria,   advisories,  or  lowest-
observed-adverse-effect   levels   (LOAELs) to
compare with the SLWC values.  As  would be
expected,  the majority of chemicals had SLWC
larger   than  existing  water  quality  criteria,
advisories,  or  LOAELs   for   aquatic   life.
However,  the  screen  identified  classes  of
compounds  for  which   current  ambient water
quality criteria may not be adequately  protective
of  wildlife:    chlorinated  alkanes,  benzenes,
phenols, metals,  DDT,  and  dioxins.  Many of
these compounds  are  produced  in very  large
amounts  and have a  variety  of  uses (e.g.,
solvents, flame retardants, organic syntheses of
fungicides and  herbicides, and manufacture of
plastics and textiles. The manufacture and use of
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these materials produce waste byproduct).  Also,
5  of the 21  are  among the top 25 pollutants
identified at Superfund sites in 1985 (3 metals, 2
organics).

Following this initial effort, EPA held a national
meeting  in April 19921 to constructively discuss
and evaluate proposed methodologies for deriving
wildlife  criteria to  build consensus  among the
scientific community as to the most defensible
scientifically approach (es) to be pursued  by EPA
in developing useful and effective wildlife criteria.

The  conclusions of this national meeting were as
follows:

•    wildlife criteria should have a tissue-residue
     component when appropriate;

•    peer-review of wildlife criteria and data sets
     should be used  in their derivation;

•    wildlife criteria should incorporate methods
     to establish site-specific wildlife criteria;

•    additional amphibian and reptile toxicity data
     are  needed;

•    further   development   of   inter-species
     lexicological  sensitivity factors are needed;
     and
proposed wildlife criteria are based on the current
EPA noncancer  human health criteria approach.
In  this  proposal,  in  addition  to   requesting
comments on  the proposed Great Lakes criteria
and methods,  EPA also requested comments on
possible  modifications  of the  proposed  Great
Lakes   approach   for  consideration   in   the
development of national wildlife criteria.

3.5.6  Numeric Criteria for Wetlands

Extension of the EPA national 304(a) numeric
aquatic life criteria to  wetlands  is recommended
as part  of a program  to develop standards and
criteria  for  wetlands.    Appendices  D and  E
provide an overview of the need for standards and
criteria for wetlands. The 304(a) numeric aquatic
life criteria  are  designed to be protective  of
aquatic life for surface waters and are generally
applicable to most  wetland types.  Appendix E
provides a possible approach, based on the site-
specific guidelines, for detecting  wetland  types
that might not be protected by direct application
of national 304(a) criteria.  The evaluation can be
simple and inexpensive for those wetland  types
for which sufficient water chemistry and species
assemblage data are available,  but will be less
useful for wetland types for which these data are
not readily available.   In Appendix E, the site-
specific approach is described and recommended
for wetlands for  which  modification of the 304(a)
numeric criteria  are considered  necessary.   The
results of this type  of evaluation, combined with
information  on local or regional  environmental
threats,  can  be used to prioritize wetland  types
(and individual criteria) for  further site-specific
evaluations  and/or additional   data  collection.
Close coordination among regulatory agencies,
wetland scientists,  and criteria  experts will be
required.
•    criteria methods should measure biomarkers
     in conjunction with other studies.

On  April  16,  1993,  EPA  proposed  wildlife
criteria  in  the Water Quality Guidance for the
Great Lakes  System (58  F.R.  20802).   The
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                                         Endnotes
1. Proceedings in production.
        Contact:   Ecological Risk Assessment Branch (4304)
                  U.S. Environmental Protection Agency
                  401 M Street, S.W.
                  Washington, DC 20460
                  Telephone (202) 260-1940
                              ; On October %  i§93,  the
                           Assistant Adminisfraitor for Wafer
                           the 0$K£vjWater\P0Uc$ mid
                           Implementation  qf Aqmfic Etfe
                               Since the policy document was signed
                           lo late fer mclmm m 'tte pandbook, the
                           complete policy document is being sent to
                           the  recipients  of this  Handbook under
                           separate cover. Later this fiscal year, you
                           will receive an update to the Handbook, to
                           be inserted  IB the  JMiowing  reserved
                           section,  reflecting the policy document.
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                                                                Chapter 4 - Antidegradation
                                 CHAPTER 4

                            ANTIDEGRADATION

                               (40 CFR 131.12)


                              Table of Contents


4.1 History of Antidegradation  	4-1

4.2 Summary of the Antidegradation Policy  	4-1

4.3 State Antidegradation Requirements	4-2

4.4 Protection of Existing Uses - 40 CFR 131.12(a)(l)  	4-3
    4.4.1     Recreational Uses  	„ .  . 4-4
    4.4.2     Aquatic Life/Wildlife Uses	4-5
    4.4.3     Existing Uses and Physical Modifications	4-5
    4.4.4     Existing Uses and Mixing Zones  	4-6

4.5 Protection of Water Quality in High-Quality Waters  - 40 CFR 131.12(a)(2)  	4-6

4.6 Outstanding National Resource Waters (ONRW) - 40 CFR 131.12(a)(3)  	4-8

4.7 Antidegradation Application and Implementation	4-10
    4.7.1     Antidegradation, Load Allocation, Waste Load Allocation, Total Maximum
              Daily Load, and Permits  	4-10
    4.7.2     Antidegradation and  the Public Participation Process	  4-11

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                                                                       Chapter 4 - Antidegradation
                                       CHAPTER 4
                                  ANTIDEGRADATION
This   chapter   provides   guidance   on   the
antidegradation  component  of  water quality
standards,  its application   in conjunction  with
the other parts  of the water quality  standards
regulation,  and  its  implementation   by  the
States. Antidegradation implementation  by the
States  is based  on a  set  of procedures to be
followed when  evaluating activities  that  may
impact the quality of the  waters  of the United
States.  Antidegradation   implementation  is an
integral   component    of  a  comprehensive
approach  to protecting  and enhancing water
quality.
 4.11   History of Antidegradation
The first antidegradation  policy statement was
released  on February 8, 1968, by the Secretary
of the U.S. Department  of the  Interior.  It was
included in EPA1 s first Water Quality Standards
Regulation (40 CFR  130.17,40 F.R. 55340-41,
November 28, 1975), and was slightly refined
and  re-promulgated  as  part  of the  current
program regulation published on November 8,
1983 (48  F.R.  51400,  40  CFR  131.12).
Antidegradation  requirements and methods  for
implementing  those requirements  are minimum
conditions  to  be included  in  a  State's  water
quality   standards.       Antidegradation    was
originally based  on the spirit, intent, and goals
of the  Act, especially the clause  "... restore
and  maintain   the  chemical,  physical  and
biological  integrity  of  the  Nation's  waters"
(101 (a))  and the provision of 303(a) that  made
water quality  standards   under  prior law  the
"starting  point"   for  CWA  water  quality
requirements.   Antidegradation  was explicitly
incorporated in the CWA through:

•    a  1987  amendment codified  in  section
     303(d)(4)(B)   requiring   satisfaction   of
     antidegradation
     making   certain
     permits; and
requirements
changes   in
 before
NPDES
     the  1990 Great  Lakes  Critical  Programs
     Act codified in CWA  section  118(c)(2)
     requiring  EPA  to  publish  Great  Lakes
     water   quality   guidance   including
     antidegradation    policies   and    imple-
     mentation  procedures.
         Summary of  the
         Policy
      Antidegradation
Section  131.12(a)(l),  or  "Tier 1," protecting
"existing uses," provides the absolute  floor  of
water quality in all waters of the United States.
This paragraph  applies a  minimum  level  of
protection to all waters.

Section  131.12(a)(2),  or  "Tier 2," applies  to
waters whose quality exceeds that necessary  to
protect  the  section 101(a)(2) goals of the Act.
In this case, water quality may not be lowered
to less than  the level necessary to fully protect
the  "fishable/swimmable"   uses   and   other
existing uses and may be lowered even to  those
levels  only  after  following  all  the provisions
described in section  131.12(a)(2).

Section  131.12(a)(3),  or  "Tier 3," applies  to
Outstanding     National    Resource    Waters
(ONRW)  where the  ordinary use classifications
and supporting  criteria may not be sufficient  or
appropriate.   As described  in the  preamble  to
the Water Quality Standards Regulation, "States
may allow some limited activities  which  result
in temporary and  short-term changes  in  water
quality," but such  changes in water quality
should  not  impact  existing uses  or alter the
essential character  or special use  that makes
the water an ONRW.
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The  requirement  for potential  water quality
impairment  associated with thermal discharges
contained  in  section  131.12  (a)(4)  of  the
regulation   is  intended   to   coordinate   the
requirements   and   procedures   of   the
antidegradation policy with those established in
the   Act   for   setting   thermal   discharge
limitations.  Regulations implementing section
316  may be found  at 40 CFR 124.66.  The
statutory scheme and legislative history indicate
that  limitations  developed  under  section  316
take  precedence over other requirements of the
Act.

As the States began  to focus more attention on
implementing  their antidegradation policies, an
additional concept was developed by the States,
which EPA  has  accepted even  though  not
directly mentioned in previous EPA guidance or
in the  regulation.    This  concept,  commonly
known  as "Tier 21/2,"is an application  of the
antidegradation policy that has implementation
requirements  that are more stringent than for
"Tier2"(high-quality waters), but somewhat  less
stringent  than  the  prohibition  against   any
lowering of water quality in "Tier3"(ONRWs).
EPA  accepts  this  additional   tier   in  State
antidegradation  policies because it is clearly a
more  stringent  application   of the  Tier  2
provisions  of the  antidegradation  policy  and,
therefore, permissible under section 510 of the
CWA.

The   supporting   rationale  that  led to  the
development  of the Tier  2Vz concept  was  a
concern  by the States that the Tier  3 ONRW
provision was so stringent  that  its application
would likely prevent  States from taking actions
in   the  future  that  were   consistent   with
important social and economic  development on,
or upstream  of,  ONRWs.  This concern  is a
major reason  that  relatively few water bodies
are  designated  as  ONRWs.    The  Tier 2Vi
approach allows States to provide a  very high
level  of  water   quality  protection   without
precluding  unforeseen  future  economic   and
social development  considerations.
         State Antidegradation Requirements
Each  State  must develop, adopt, and retain a
statewide   antidegradation   policy  regarding
water   quality    standards    and    establish
procedures  for its implementation  through the
water quality management process.  The State
antidegradation   policy   and  implementation
procedures   must   be  consistent   with  the
components detailed  in 40 CFR 131.12.  If not
included in the standards  regulation of a State,
the policy must be specifically referenced  in the
water quality  standards  so  that  the  functional
relationship  between  the   policy   and  the
standards  is clear. Regardless of the location of
the  policy, it  must  meet   all  applicable
requirements.      States   may   adopt
antidegradation   statements   more  protective
than   the   Federal   requirement.      The
antidegradation   implementation   procedures
specify how the  State will determine  on a case-
by-case basis whether, and to what extent, water
quality may be lowered.

State   antidegradation    polices  and  imple-
mentation  procedures are subject to review by
the Regional  Administrator.    EPA has  clear
authority  to review and approve or disapprove
and promulgate  an antidegradation policy for a
State.   EPA's review  of the implementation
procedures   is  limited   to   ensuring  that
procedures  are  included that describe how the
State  will implement the required elements of
the   antidegradation   review.     EPA  may
disapprove and  federally promulgate all or part
of  an   implementation   process   for
antidegradation   if,  in  the  judgment  of the
Administrator,  the  State's  process  (or  certain
provisions thereof)  can be implemented  in such
a  way as  to circumvent the intent  and purpose
of the antidegradation policy.  EPA encourages
submittal  of any amendments  to the statement
and implementing  procedures to the Regional
Administrator  for pre-adoption  review  so that
the State  may take EPA comments into account
prior to final action.
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                                                                           Chapter 4 - Antldegradation
 If a  State's  antidegradation   policy  does  not
 meet  the  Federal   regulatory   requirements,
 either through  State  action  to revise its policy
 or  through revised Federal  requirements,  the
 State would be given the opportunity  to  make
 its policy consistent with the regulation.  If this
 is  not  done,   EPA   has   the  authority   to
 promulgate the policy for the State pursuant to
 section 303(c)(4) of the Clean Water  Act (see
 section 6.3, this Handbook).
          Protection of Existing Uses - 40 CFR
 This section requires the protection  of existing
 uses and the level of water quality to protect
 those uses. An "existing use" can be established
 by demonstrating  that:

 •    fishing,  swimming,  or  other  uses  have
     actually   occurred  since  November  28,
      1975; or

 •    that the  water quality is suitable to  allow
     the  use  to be  attained—unless   there  are
     physical  problems, such  as  substrate  or
     flow, that  prevent  the   use  from  being
     attained.

 An  example  of  the latter is an  area  where
 shellfish  are  propagating  and surviving in  a
 biologically suitable habitat  and are available
 and suitable for harvesting  although,  to date, no
 one has attempted to harvest  them.  Such facts
 clearly  establish that shellfish harvesting  is an
 "existing"  use,   not    one   dependent    on
 improvements   in water  quality.    To   argue
 otherwise would be to  say that  the  only time an
 aquatic  protection  use  "exists" is if someone
 succeeds  in catching fish.

 Full protection  of  the  existing use  requires
protection of the entire  water  body  with  a few
 limited   exceptions  such  as   certain  physical
 modifications  that may  so alter  a water  body
that species composition cannot be maintained
 (see section 4.4.3,this Handbook),  and mixing
zones (see section 4.4.4,this Handbook).   For
example, an activity that lowers  water quality
such  that  a buffer zone must be  established
within a previous shellfish  harvesting  area is
inconsistent  with the antidegradation  policy.

Section  131.12(a)(l) provides the absolute floor
of water quality in all  waters of  the  United
States. This paragraph  applies  a minimum level
of protection to  all waters.  However, it is most
pertinent to waters having  beneficial uses that
are less  than the section 101(a)(2) goals of the
Act.  If it can be proven, in that situation,  that
water  quality  exceeds that  necessary to fully
protect the existing use(s)  and exceeds water
quality standards but is not  of  sufficient quality
to cause a better use to  be  achieved, then that
water  quality  may  be  lowered  to  the  level
required to fully protect the existing use as long
as  existing  water   quality  standards   and
downstream  water quality  standards  are  not
affected.  If this does  not involve a change in
standards,  no public hearing would be required
under    section    303(c).   However,   public
participation   would  still   be   provided   in
connection  with the  issuance of a  NPDES
permit or amendment  of a  section 208 plan or
section  319 program.    If, however, analysis
indicates  that  the  higher  water  quality does
result  in a better use, even if not  up to  the
section 101(a)(2) goals, then the  water quality
standards must be upgraded to reflect the uses
presently being attained  (131.10(i)).

If a planned  activity  will foreseeably  lower
water  quality to  the  extent  that it no longer is
sufficient to protect  and maintain the existing
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uses  in  that  water  body,  such an  activity is
inconsistent with EPA's antidegradation  policy,
which requires that  existing  uses are  to be
maintained.    In  such  a  circumstance,   the
planned  activity must be avoided  or  adequate
mitigation   or preventive  measures  must be
taken to ensure  that the existing uses and  the
water   quality   to  protect   them   will  be
maintained.

Section  4.4.1,  this  Handbook,  discusses  the
determination  and protection   of  recreational
"existing"  uses,  and   section  4.4.2,    this
Handbook,  discusses  aquatic   life protection
"existing" uses (of  course, many other types of
existing uses may occur in a water body).

4.4.1     Recreational Uses

Recreational  uses traditionally  are divided into
primary   contact   and    secondary   contact
recreation  (e.g., swimming vs. boating;  that is,
recreation   "in" or "on"  the  water.)  However,
these  two   broad  uses   can   logically  be
subdivided into a variety of subcategories  (e.g.,
wading,  sailing, power boating,  rafting).   The
water  quality  standards   regulation   does not
establish a  level of specificity  that each  State
must apply in  determining  what  recreational
"uses" exist.  However, the following principles
apply.

•    The State selects the level of specificity it
     desires for identifying recreational existing
     uses (that  is, whether  to  treat  secondary
     contact  recreation  as  a  single  use or to
     define   subcategories    of   secondary
     recreation).  The State  has two limitations:

          the  State must be at  least as specific
          as the uses listed in  sections 101 (a)
          and 303(c) of the Clean Water  Act;
          and

         the  State must be at  least as specific
          as  the  written  description  of the
          designated  use  classifications adopted
          by the State.
•    If the State designated  use classification
     system   is  very   specific  in  describing
     subcategories    of  a   use,   then   such
     specifically  defined uses, if they exist, must
     be protected  fully under  antidegradation.
     A  State   with  a  broadly   written   use
     classification  system may, as a matter of
     policy,  interpret  its  classifications  more
     specifically    for   determining    existing
     uses—as long as it is done consistently.  A
     State   may   also   redefine   its    use
     classification   system,   subject    to   the
     constraints  in 40 CFR  131.10, to  more
     adequately  reflect existing uses.

•    If the use classification system  in a State is
     defined  in  broad  terms  such  as  primary
     contact    recreation,    secondary   contact
     recreation,  or boating, then it is  a  State
     determination  whether to allow changes in
     the type of primary  or secondary  contact
     recreation   or  boating  activity that would
     occur on  a  specific water body as  long as
     the basic use  classification  is met.    For
     example,  if a State defines a use simply as
     "boating,"it is the State's decision whether
     to allow  something  to occur  that would
     change  the  type of boating from canoeing
     to power boating  as long as the resulting
     water quality allows the "boating" use to be
     met.  (The public  record used originally to
     establish  the  use  may provide  a  clearer
     indication   of  the  use   intended  to be
     attained  and protected  by the  State.)

The rationale is  that the required  water quality
will allow a boating use  to continue and that
use meets  the goal of the Act.  Water quality is
the key. This  interpretation  may allow a  State
to  change  activities   within  a  specific   use
category but it does not create a mechanism to
remove use  classifications;  this latter action is
governed   solely by  the   provisions  of  the
standards  regulation (CWA section 131.10(g)).

One situation where EPA might conceivably be
called   upon  to  decide  what constitutes  an
existing use is where EPA is writing an NPDES
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                                                                         Chapter 4 - Antidegradation
permit. EPA has the responsibility under CWA
section  301(b)(l)(C)   to  determine  what  is
needed  to  protect  existing  uses  under  the
State's  antidegradation    requirement,    and
accordingly  may  define  "existing uses"  or
interpret  the  State's  definition  to  write  that
permit if the State  has not done so.  Of course,
EPA's determination  would be subject to State
section 401 certification  in such a case.

4.4.2     Aquatic Life/Wildlife Uses

No    activity   is    allowable   under   the
antidegradation policy which would  partially or
completely  eliminate  any existing use whether
or not that use is designated  in a State's water
quality standards.  The aquatic protection use is
a broad category requiring further explanation.
Non-aberrational   resident   species  must  be
protected,  even if not prevalent  in  number or
importance.  Water quality should be such  that
it  results  in no mortality and  no  significant
growth or  reproductive impairment  of resident
species.  Any  lowering of water quality below
this full level of protection is not allowed.

A State  may develop  subcategories  of aquatic
protection   uses  but  cannot  choose different
levels  of protection  for like uses. The fact  that
sport  or commercial fish are not present  does
not mean that  the water  may not be  supporting
an aquatic  life protection  function.   An existing
aquatic  community  composed  entirely   of
invertebrates and  plants, such as may be found
in a pristine alpine tributary stream,  should  still
be protected   whether or not   such a  stream
supports a fishery.

Even    though  the   shorthand   expression
"fishable/swimmable"  is  often used, the actual
objective of the Act is to "restore and maintain
the chemical, physical, and biological  integrity
of our Nation's waters"  (section 101(a)).  The
term   "aquatic  life"  would  more  accurately
reflect the  protection of the aquatic  community
that was intended  in  section  101(a)(2)  of the
Act.
Section 131.12(a)(l) states, "Existing instream
water uses and level of water quality necessary
to protect the existing uses shall be maintained
and protected." For example, while sustaining a
small coldwater fish population, a stream  does
not  support  an  existing  use  of a  "coldwater
fishery."The existing stream temperatures  are
unsuitable  for a thriving coldwater fishery. The
small marginal  population  is  an artifact and
should not  be employed  to mandate  a more
stringent  use (true  coldwater  fishery) where
natural conditions are not suitable for that use.

A use attainability  analysis or other  scientific
assessment   should  be   used   to  determine
whether the aquatic life population  is in fact an
artifact or is a stable population  requiring water
quality protection.   Where species appear  in
areas not normally  expected, some  adaptation
may have occurred and site-specific criteria may
be   appropriately    developed.   Should   the
coldwater   fish   population   consist  of   a
threatened   or  endangered  species,  it  may
require   protection   under  the   Endangered
Species Act.  Otherwise, the stream need only
be protected  as a warmwater fishery.

4.4.3    Existing   Uses  and   Physical
         Modifications

A literal  interpretation  of40CFR 131.12(a)(l)
could prevent certain physical modifications  to
a water body that  are  clearly  allowed  by the
Clean   Water  Act,   such  as  wetland   fill
operations  permitted  under section  404 of the
Clean  Water  Act.   EPA interprets  section
131.12(a)(l) of the antidegradation policy to be
satisfied  with regard to fills in wetlands  if the
discharge   did   not   result   in   "significant
degradation"   to  the  aquatic   ecosystem  as
defined under section  230.10(c) of the section
4Q4(b)(l) Guidelines.

The  section 404(b)(l) Guidelines  state  that the
following   effects   contribute   to   significant
degradation,  either  individually or collectively:
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     . . . significant adverse effects on  (1)
     human  health or  welfare,  including
     effects on municipal  water supplies,
     plankton,  fish, shellfish, wildlife, and
     special aquatic  sites (e.g., wetlands);
     (2) on the life  stages of aquatic life
     and   other   wildlife  dependent   on
     aquatic   ecosystems,  including  the
     transfer,  concentration,  or spread  of
     pollutants or their byproducts beyond
     the site through biological, physical,
     or chemical process; (3) on ecosystem
     diversity,  productivity, and stability,
     including  loss  of  fish  and  wildlife
     habitat  or loss  of the capacity of a
     wetland to assimilate nutrients,  purify
     water, or reduce wave energy;  or (4)
     on    recreational,    aesthetic,    and
     economic values.

These  Guidelines  may  be used  by States to
determine  "significant degradation" for wetland
fills.  Of course,  the States are free to adopt
stricter  requirements  for wetland fills in their
own antidegradation  polices, just as they  may
adopt  any other  requirement   more  stringent
than  Federal  law  requires.     For  additional
information  on   the  linkage  between  water
quality  standards  and the section 404 program,
see Appendix D.

If any wetlands were found to have better water
quality  than  "fishable/swimmable,"  the State
would be allowed to lower water quality to the
no significant degradation  level as long as the
requirements   of  section   131.12(a)(2)   were
followed.   As  for the  ONRW  provision  of
antidegradation   (131.12(a)(3)),   there   is  no
difference  in the way it applies to  wetlands and
other water bodies.

4.4.4     Existing  Uses and Mixing Zones

Mixing zones are  another  instance  when the
entire  extent of the water body is not required
to be  given  full existing use  protection.   The
area within a properly designated mixing zone
(see   section  5.1)  may  have  altered  benthic
habitat   and a  subsequent   alteration   of the
portions of the aquatic community.  Any effect
on the existing use must be limited to the area
of the regulatory mixing zone.
          Protection of Water Quality in High-
          Quality Waters - 40 CFR 131.12(a)(2)
This section provides general program guidance
in  the  development   of procedures  for  the
maintenance   and  protection  of water  quality
where the quality  of the water exceeds levels
necessary  to  support   propagation  of  fish,
shellfish,  and wildlife and recreation in and on
the  water.    Water  quality  in  "high-quality
waters" must be maintained and protected  as
prescribed in section  131.12(a)(2) of the WQS
regulation.
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                                                                          Chapter 4 - Antidegradation
 High-quality  waters  are those  whose quality
 exceeds that necessary  to  protect  the section
 101(a)(2)  goals of the  Act,  regardless of  use
 designation.  All parameters do not need  to be
 better  quality than the State's ambient criteria
 for the water  to be deemed  a  "high-quality
 water." EPA believes that it is  best  to  apply
 antidegradation  on  a parameter-by-parameter
 basis.  Otherwise, there  is potential for a large
 number of waters not to receive antidegradation
 protection, which is important to attaining  the
 goals of the  Clean Water Act to restore   and
 maintain  the integrity of the  Nation's waters.
 However,    if   a   State   has    an   official
 interpretation   that    differs   from   this
 interpretation,  EPA  will  evaluate  the  State
 interpretation    for   conformance   with   the
 statutory   and   regulatory   intent   of   the
 antidegradation   policy.    EPA  has  accepted
 approaches that do not use a strict pollutant-by-
 pollutant basis  (USEPA,  1989c).

 In "high-quality  waters," under  131.12(a)(2),
 before any  lowering of  water quality occurs,
 there   must  be   an  antidegradation   review
 consisting  of:

 •     a  finding  that   it   is  necessary  to
      accommodate   important  economical  or
      social development   in the area  in which
      the waters are  located   (this  phrase  is
      intended  to  convey a  general  concept
     regarding   what  level   of   social   and
     economic  development  could be used to
     justify a change in high-quality waters);

 •    full satisfaction   of  all intergovernmental
     coordination  and   public   participation
     provisions  (the  intent  here  is  to ensure
     that   no activity  that   will  cause water
     quality to  decline in existing  high-quality
     waters  is  undertaken  without  adequate
     public  review   and  intergovernmental
     coordination); and

•    assurance  that  the  highest statutory  and
     regulatory requirements  for point  sources,
     including    new   source   performance
      standards, and best management practices
      for nonpoint  source pollutant controls  are
      achieved  (this  requirement  ensures  that
      the  limited  provision  for lowering water
      quality  of high-quality  waters  down  to
      "fishable/swimmable"  levels  will  not  be
      used to  undercut  the  Clean  Water  Act
      requirements    for  point   source   and
      nonpoint    source   pollution    control;
      furthermore,  by ensuring  compliance with
      such statutory   and  regulatory  controls,
      there  is  less chance that  a lowering  of
      water     quality   will   be   sought   to
      accommodate  new  economic  and  social
      development).

 In addition,  water quality may not  be lowered
 to less than  the level necessary to fully protect
 the  "fishable/swimmable"   uses   and  other
 existing uses.  This  provision  is  intended   to
 provide  relief only  in  a few extraordinary
 circumstances  where  the economic and  social
 need  for the  activity clearly  outweighs  the
 benefit of maintaining water quality above that
 required  for "fishable/swimmable"  water, and
 both  cannot  be   achieved.    The  burden  of
 demonstration  on the individual proposing such
 activity  will  be   very  high.    In   any  case,
 moreover, the existing use must be maintained
 and  the  activity  shall  not   preclude   the
 maintenance of a "fishable/swimmable" level of
 water quality protection.

 The antidegradation review requirements of this
 provision  of  the  antidegradation   policy  are
 triggered  by any action  that would result in the
 lowering  of  water quality in  a  high-quality
 water.   Such  activities  as  new  discharges  or
 expansion   of  existing  facilities   would
 presumably lower  water quality and would not
 be permissible unless  the State  conducts  a
 review consistent  with the previous  paragraph.
 In addition,  no permit  may be issued, without
 an antidegradation  review, to  a discharger  to
 high-quality  waters with effluent limits greater
than actual current loadings if such loadings will
cause  a lowering  of water  quality  (USEPA
 1989c).
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Antidegradation   is not a "no growth" rule and
was never designed or intended to be such.  It
is a  policy that  allows public decisions  to  be
made  on  important  environmental   actions.
Where  the  State  intends  to  provide  for
development, it  may decide under this section,
after   satisfying   the   requirements   for
intergovernmental   coordination   and  public
participation,  that  some   lowering  of  water
quality in "high-quality waters" is necessary  to
accommodate  important   economic  or  social
development.   Any such  lower water quality
must protect existing  uses fully, and the State
must  assure that  the highest  statutory  and
regulatory requirement  for all new and existing
point  sources   and   all   cost-effective  and
reasonable  BMPs for  nonpoint source control
are being achieved on the water body.

 4.61   Outstanding   National   Resource
         Waters   (ONRW)   -   40   CFR
Outstanding    National    Resource    Waters
(ONRWs)  are provided  the highest level of
protection  under  the antidegradation   policy.
The  policy provides for protection  of  water
quality in high-quality waters that constitute  an
ONRW  by prohibiting  the lowering of water
quality.  ONRWs are often regarded  as highest
quality  waters  of the United  States:  That is
clearly  the thrust  of 131.12(a)(3).  However,
ONRW   designation    also   offers  special
protection  for waters of "exceptional  ecological
significance." These  are  water bodies that  are
important,  unique, or sensitive ecologically, but
whose  water   quality,  as  measured  by  the
traditional  parameters  such as dissolved oxygen
or pH,  may not be  particularly  high or whose
characteristics   cannot be adequately  described
by these parameters  (such as wetlands).

The  regulation  requires  water  quality  to  be
maintained  and protected in ONRWs.  EPA
interprets  this  provision  to  mean no  new or
increased discharges to ONRWs  and  no new or
increased discharge  to  tributaries  to ONRWs
that  would result in lower water quality  in the
      OUTSTANDING NATIONAL
          RESOURCE WATERS

       The highest level  of protection
       under the antidegradation  policy's
       Tier 3.

       High-quality   or   ecologically
       unique   waters   such  as  those
       within the jurisdiction of National
       and  State  Parks  and  Wildlife
       refuges.
ONRWs.     The   only   exception  to   this
prohibition,  as discussed in the preamble to the
Water  Quality  Standards  Regulation  (48 F.R.
51402), permits States  to allow some limited
activities   that   result   in   temporary    and
short-term   changes  in  the  water  quality  of
ONRW.  Such  activities must not permanently
degrade water quality or result in water quality
lower than that  necessary  to protect the existing
uses in the  ONRW.  It is difficult to give an
exact definition of "temporary" and  "short-term"
because of the variety of activities that might be
considered.   However,  in rather broad  terms,
EPA's view of temporary  is weeks and months,
not years. The intent of EPA's provision clearly
is  to limit  water  quality degradation  to the
shortest possible time. If a construction activity
is  involved,  for example,  temporary  is defined
as the  length of time necessary to construct the
facility and  make  it operational.   During any
period  of  time  when,  after  opportunity  for
public  participation in  the decision,  the State
allows  temporary  degradation,   all  practical
means of minimizing such degradation shall be
implemented.   Examples  of situations in which
flexibility is appropriate  are listed in Exhibit 4-
1.
4-8
                                      (9/15/93)

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                                                                               Chapter 4 - Antidegradation
       Example 1  A national park wishes to replace a defective septic tank-drainfield
                      system in a campground,  lite campground is located immediately
                      adjacent to a small stream with the ONRW use designation.
                       Under the regulation, the construction could occur if best management practices were
                       scrupulously followed to minimize any disturbance of water quality or aquatic habitat.
                       Same situation except the campground is served by a small sewage
                       treatment plant already discharging to the ONRW.  It is desired to
                       enlarge the treatment system and provide higher levels of treatment.
                       Under the regulation, this water-quality-enhancing action would be permitted if there was
                       only temporary increase in sediment and, perhaps, in organic loading, which would occur
                       during the actual construction phase,
       Example 3  A National forest with a mature, second growth of trees which are
                       suitable for harvesting,  with associated road repair and
                       re-stabilization.  Streams in the area are designated as ONRW and
                       support trout fishing.
                       The regulation intends that best management practices for timber harvesting be followed
                       and might include preventive measures more stringent than for similar logging in less
                       environmentally sensitive areas.  Of course, if the lands were being considered for
                       designation as wilderness areas or other similar designations, EPA's regulation should not
                       he construed as encouraging or condoning timbering operations. The regulation allows
                       only temporary and short-term Water quality degradation while maintaining existing uses
                       or new uses consistent with the purpose of the management of the QNRW area.
       Other examples of these types of activities include maintenance and/or repair of existing boat ramps or boat
       docks, restoration of existing sea walls, repair of existing stonnwater pipes, and replacement or repair of
       existing bridges.
    Exhibit 4-1.   Examples  of  Allowable  Temporary  Lowering  of  Water  Quality  in
                    Outstanding National Resource Waters
(9/15/93)                                                                                            4-9

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Water Quality Standards Handbook - Second Edition
 4.71    Antidegradation   Application   and
^™™    Implementation

Any one or a combination  of several activities
may trigger the antidegradation policy analysis.
Such activities include a scheduled water quality
standards  review, the establishment  of new  or
revised load allocations, waste load allocations,
total maximum daily loads, issuance of NPDES
permits, and  the demonstration   of  need  for
advanced  treatment  or request by private  or
public  agencies or individuals for a special study
of the  water body.

Nonpoint  source  activities are not exempt from
the provisions of the  antidegradation  policy.
The language of section  131.12 (a)(2)  of the
regulation:  "Further, the  State shall assure that
there  shall  be achieved  the  highest  statutory
and  regulatory requirements  for  all  new and
existing point  sources and all cost-effective and
reasonable  best  management  practices  for
nonpoint  source  control ..." reflects statutory
provisions of the Clean Water Act. While it is
true that the Act does not establish a federally
enforceable  program  for nonpoint sources, it
clearly  intends that the BMPs developed and
approved  under sections 205(j),208,303(e), and
319 be aggressively implemented by the States.

4.7.1  Antidegradation,    Load   Allocation,
       Waste Load Allocation, Total Maximum
       Daily Load, and Permits

In  developing  or  revising  a  load  allocation
(LA),  waste load allocation  (WLA),  or total
maximum daily  load  (TMDL) to reflect new
information  or to provide  for seasonal variation,
the antidegradation policy, as an integral part of
the State  water  quality  standards,  must  be
applied as discussed  in this  section.

The TMDL/WLA/LA  process distributes the
allowable  pollutant  loadings to a water  body.
Such allocations  also consider the contribution
to pollutant  loadings from nonpoint  sources.
This process must reflect applicable State  water
quality  standards  including  the antidegradation
policy.    No  waste  load  allocation  can  be
developed  or NPDES permit issued that would
result in standards being violated. With respect
to antidegradation,   that  means  existing  uses
must  be protected,  water  quality may not  be
lowered  in ONRWs,  and in the case of waters
whose quality  exceeds that  necessary  for the
section  101(a)(2)  goals of the  Act, an activity
cannot  result  in  a  lowering of  water quality
unless  the  applicable  public  participation,
intergovernmental review, and baseline control
requirements of the antidegradation  policy have
been  met.  Once the LA,  WLA,  or TMDL
revision  is  completed,  the  resulting permits
must incorporate discharge limitations based  on
this revision.

When  a  pollutant  discharge  ceases  for any
reason,  the waste load  allocations for the other
dischargers  in the  area may  be  adjusted  to
reflect   the   additional   loading   available
consistent with the antidegradation  policy under
two circumstances:

•    In  "high-quality waters" where after the full
     satisfaction  of all  public participation and
     intergovernmental   review  requirements,
     such adjustments are  considered necessary
     to  accommodate  important  economic  or
     social  development,  and  the   "threshold"
     level  requirements  (required   point  and
     nonpoint  source controls)  are  met.

•    In less than  "high-quality waters," when the
     expected   improvement  in water quality
     (from  the  ceased  discharge)   would not
     cause a better use to be achieved.

The adjusted loads still must meet water quality
standards,  and the new waste load  allocations
must  be  at least as  stringent  as  technology-
based  limitations.   Of course, all applicable
requirements of the  section 402 NPDES permit
regulations would have to be satisfied before a
permittee could increase its discharge.

If a  permit  is  being  renewed,  reissued  or
modified  to include  less  stringent  limitations
4-10
                                       (9/15/93)

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                                                                         Chapter 4 - Antidegradatlon
based  on  the  revised LA/WLA/TMDL,   the
same antidegradation   analysis applied  during
the LA/WLA/TMDL  stage would apply during
the permitting  stage. It would be reasonable  to
allow   the    showing   made    during   the
LA/WLA/TMDL     stage    to    satisfy   the
antidegradation  showing at  the  permit stage.
Any restrictions to less stringent limits based on
antibacksliding would also apply.

If a State  issues an NPDES permit that  violates
the required  antidegradation   policy, it would be
subject  to  a  discretionary   EPA veto under
section  402(d)  or to  a citizen  challenge.   In
addition to actions  on permits, any waste  load
allocations  and   total  maximum daily  loads
violating the antidegradation  policy are subject
to EPA disapproval and EPA promulgation  of
a  new  waste  load  allocation/total  maximum
daily load under section 303(d) of the Act. If a
significant pattern  of violation  was  evident,
EPA could  constrain   the award  of grants  or
possibly  revoke    any  Federal  permitting
capability that  had been delegated to the State.
Where  EPA  issues an NPDES  permit, EPA
will, consistent  with its NPDES regulations, add
any  additional  or  more   stringent   effluent
limitations required to ensure compliance  with
the  State antidegradation  policy  incorporated
into  the  State water  quality standards.   If  a
State  fails   to  require  compliance   with its
antidegradation   policy through  section  401
certification  related to permits issued  by other
Federal  agencies  (e.g., a  Corps of Engineers
section  404  permit),  EPA   could  comment
unfavorably upon  permit issuance. The public,
of course, could bring pressure upon the permit
issuing agency.

For example applications  of antidegradation  in
the WLA and permitting process, see Exhibit 4-
2.

4.7.2  Antidegradation   and   the   Public
       Participation Process

Antidegradation,   as with  other  water  quality
standards  activities, requires public participation
and  intergovernmental   coordination  to be an
effective tool in the water quality management
process.  40 CFR  131.12(a)(2) contains  explicit
requirements   for  public   participation   and
intergovernmental   coordination   when
determining   whether  to  allow  lower water
quality in high-quality waters. Nothing in either
the water  quality  standards or the waste  load
allocation regulations requires the same degree
of public  participation   or intergovernmental
coordination for such non-high-quality waters as
is required  for high-quality waters.  However
public participation  would  still be  provided  in
connection  with  the issuance  of a NPDES
permit or  amendment  of a 208 plan.  Also,  if
the action  that causes  reconsideration   of the
existing  waste loads   (such  as  dischargers
withdrawing from the  area) will result in an
improvement   in  water  quality  that  makes   a
better use  attainable,  even  if not up to the
"fishable/swimmable"   goal,  then  the  water
quality  standards  must  be  upgraded and full
public  review  is  required   for  any   action
affecting changes  in standards.   Although not
specifically required by the standards regulation
between  the triennial reviews, we  recommend
that   the   State  conduct   a  use   attainability
analysis   to   determine   if  water  quality
improvement  will result  in attaining higher uses
than  currently designated  in  situations  where
significant  changes in waste loads are expected.

The    antidegradation    public   participation
requirement  may  be satisfied in several  ways.
The   State  may  hold  a  public  hearing  or
hearings.    The   State  may  also  satisfy the
requirement  by providing public notice and the
opportunity for the public to request a hearing.
Activities that  may affect several water bodies
in a river basin or sub-basin  may be considered
in a  single  hearing.   To  ease  the resource
burden on both the State and public,  standards
issues may  be combined   with hearings  on
environmental    impact    statements,   water
management plans, or permits. However, if this
is done,  the public must  be clearly  informed
that possible changes in water quality  standards
are being considered along with other  activities.
(9/15/93)
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Water Quality Standards Handbook - Second Edition
       Example 1

           Several facilities on a stream segment discharge phosphorus-containing wastes.
           Ambient phosphorus  concentrations meet the designated class B (non-
           fishable/swimmable) standards, but barely. Three dischargers achieve
           elimination by developing land treatment systems. As a result, actual water
           quality improves (i.e., phosphorus levels decline) but not quite to the level
           needed to meet class A  (ftshable/swimmable) standards. Can  the remaining
           dischargers now be allowed to increase their phosphorus discharge without an
           antidegradation analysis with the result that water quality declines (phosphorus
           levels increase) to previous levels?
           Nothing in the water quality standards regulation explicitly prohibits this. Of course, changes in their
           NPDES permit limits may be subject to non-water quality constraints, such as BPT, BAT, or the
           NPDES antibacksliding provisions, which may restrict the increased loads.
      Example 2

           Suppose, in the above situation,  water quality improves to the point that actual
           water quality now meets class A  requirements. Is the answer different?
           Yes. The standards must be upgraded (see section 2.8).
      Example 3

           As an alternative case, suppose phosphorus loadings go down and water quality
           improves because of a change in farming practices (e.g., initiation of a
           successful nonpoint source program.) Are the above answers the same?
           Yes. Whether the improvement results from a change in point or nonpoint source activity is immaterial
           to how any aspect of the standards regulation operates. Section 131.10(d) clearly indicates that uses
           are deemed attainable if they can be achieved by "... cost-effective and reasonable best management
           practices for nonpoint source control."  Section 131.12(a)(2) of the antidegradation policy contains
           essentially the same wording.
    Exhibit 4-2.   Examples of the Application of Antidegradation in the Waste Load/Load
                   Allocation and NPDES Permitting Process
4-12                                                                                      (9/15/93)

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                                                                             Chapter 4 - Antidegradation
 It  is  inconsistent   with   the   water   quality
 standards  regulation to "back-door" changes  in
 standards  through  actions  on EIS's, waste load
 allocations,  plans,  or permits.
(9/15/93)                                                                                        4_13

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                                                             Chapter 5 - General Policies
                                CHAPTER 5

                           GENERAL POLICIES

                              (40 CFR 131.13)


                             Table of Contents
5.1 Mixing Zones	5-1
    5.1.1     State Mixing Zone Methodologies   	5-2
    5.1.2     Prevention of Lethality to Passing Organisms	5-6
    5.1.3     Human Health Protection	5-7
    5.1.4     Where Mixing Zones Are Not Appropriate	5-8
    5.1.5     Mixing Zones for the Discharge of Dredged or Fill Material	5-9
    5.1.6     Mixing Zones for Aquaculture Projects  	5-9

5.2 Critical Low-Flows	5-9

5.3 Variances From Water Quality Standards  	5-11

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                                                                       Chapter 5 - General Policies
                                        CHAPTERS
                                  GENERAL POLICIES
States  may, at their  discretion,  adopt certain
policies   in   their  standards   affecting   the
application  and implementation  of standards.
For example, policies concerning mixing zones,
water quality  standards  variances,  and critical
flows for water quality-based permit limits may
be adopted.  Although these are areas of State
discretion, EPA retains authority to review and
approve  or disapprove  such policies (see  40
CFR  131.13).
         Mixing Zones
It is not  always necessary to meet all  water
quality  criteria  within the discharge  pipe  to
protect  the integrity of the  water body  as  a
whole.  Sometimes it is appropriate to allow for
ambient  concentrations  above  the criteria  in
small areas  near outfalls.   These  areas  are
called  mixing zones.  Whether  to  establish  a
mixing  zone  policy  is   a  matter  of  State
discretion, but  any  State  policy allowing for
mixing zones must be consistent with the Clean
Water  Act  and is subject to approval  of the
Regional  Administrator.

A series of guidance documents  issued by EPA
and its predecessor agencies have addressed the
concept of a mixing zone  as a limited  area  or
volume  of  water  where  initial  dilution  of  a
discharge  takes place.  Mixing zones have been
applied  in the water quality standards program
since its inception.   The present water quality
standards  regulation  allows  States'  to adopt
mixing zones as a matter  of States discretion.
Guidance  on defining  mixing zones previously
has been provided in several  EPA documents,
including  FWPCA (1968); NAS/NAE  (1972);
USEPA (1976);  and  USEPA (1983a).
EPA's current mixing zone guidance, contained
in this  Handbook  and  the  Technical Support
Document  for  Water   Quality-based  Toxics
Control  (USEPA,  1991a),  evolved  from  and
supersedes these sources.

Allowable mixing zone characteristics should be
established  to ensure that:

•  mixing zones  do not  impair the  integrity of
   the water body as a whole,

•  there  is no  lethality to organisms passing
   through the mixing zone  (see  section 5.1.2,
   this Handbook);  and

•  there   are   no   significant  health   risks,
   considering  likely pathways of exposure (see
   section 5.1.3, this Handbook).

EPA   recommends   that    mixing   zone
characteristics  be  defined  on a case-by-case
basis after it  has  been  determined  that  the
assimilative capacity of the receiving system can
safely  accommodate   the  discharge.    This
assessment  should  take  into  consideration  the
physical, chemical, and biological characteristics
of the discharge  and the receiving  system; the
life  history and  behavior of  organisms  in the
receiving system; and the desired uses  of the
waters.   Mixing zones should  not  be permitted
where they may endanger  critical  areas (e.g.,
drinking  water  supplies,  recreational  areas,
breeding  grounds, areas  with  sensitive biota).

EPA has  developed  a holistic  approach  to
determine  whether a mixing  zone is tolerable
(Brungs, 1986).  The method  considers  all the
impacts to the  water body and all the impacts
that  the  drop in  water quality  will have  on the
surrounding ecosystem and water body uses. It
is  a  multistep   data collection  and  analysis
                                                                                         5-1

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Water Quality Standards Handbook - Second Edition
procedure   that   is  particularly   sensitive   to
overlapping   mixing  zones.    This  method
includes the identification of all upstream  and
downstream  water  bodies  and  the  ecological
and  cultural  data  pertaining   to them;   the
collection  of data  on all present  and  future
discharges  to the water body; the assessment  of
relative  environmental   value  and  level   of
protection  needed  for  the  water body; and,
finally, the allocation  of environmental  impact
for a  discharge   applicant.    Because  of  the
difficulty in  collecting the  data necessary  for
this  procedure    and  the  general  lack   of
agreement   concerning   relative   values,  this
method will be difficult to  implement  in  full.
However, the method does  serve as a guide on
how to proceed  in allocating  a mixing zone.

Mixing zone allowances will increase  the mass
loadings of the pollutant to the water  body and
decrease   treatment   requirements.     They
adversely   impact   immobile  species,  such  as
benthic communities,  in the  immediate vicinity
of the  outfall.   Because  of these and other
factors, mixing zones must be applied  carefully,
so as not to impede progress toward the Clean
Water  Act goals of maintaining and improving
water  quality.    EPA  recommendations   for
allowances  for mixing zones,  and appropriate
cautions about their use, are contained  in this
section.
             MIXING ZONES

  A limited area or volume of water where
  initial dilution of a discharge takes place
  and where numeric water quality criteria
  can  be  exceeded  but  acutely  toxic
  conditions are prevented.
 The  Technical  Support Document for  Water
 Quality-based  Toxics  Control (USEPA,  1991a,
sections  2.2, 4.3, 4.4) discusses  mixing zone
analyses for situations  in which the  discharge
does  not mix completely  with  the  receiving
water  within a short distance.   Included  are
discussions  of outfall  designs  that  maximize
initial  dilution  in  the   mixing  zone,  critical
design periods for  mixing zone  analyses, and
methods to  analyze  and model  nearfield and
farfield mixing.

5.1.1 State Mixing Zone Methodologies

EPA recommends that States  have a definitive
statement in their standards on whether or not
mixing zones are allowed. Where  mixing zones
provisions are part  of the State standards,  the
State   should  describe  the  procedures  for
defining mixing zones.   Since these areas  of
impact,  if   disproportionally    large,    could
potentially  adversely unpact the productivity of
the  water   body   and   have   unanticipated
ecological   consequences,   they   should   be
carefully evaluated  and appropriately  limited in
size. As our  understanding  of pollutant  impacts
on  ecological systems evolves, cases could  be
identified where no  mixing zone is appropriate.

State  water  quality  standards  should describe
the State's  methodology  for  determining  the
location, size, shape, outfall design, and in-zone
quality  of mixing zones.   The  methodology
should   be   sufficiently  precise   to  support
regulatory  actions,  issuance  of permits, and
determination  of BMPs  for nonpoint  sources.
EPA recommends the following:

•  Location

Biologically important areas are to be identified
and protected.  Where necessary  to preserve a
zone  of passage  for migrating  fish or other
organisms  in  a water  course,  the  standards
should  specifically identify the portions  of the
waters to be kept free from mixing zones.

Where a mixing zone is allowed, water quality
standards are met at the  edge  of that  regulatory
 5-2

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                                                                        Chapter 5 - General Policies
 mixing zone during design flow conditions and    created  by water with inadequate chemical  or
 generally provide:                                physical quality.
 • a  continuous zone of passage  that  meets
   water quality criteria for free-swimming and
   drifting organisms; and

 • prevention of impainnent of critical resource
   areas.

 Individual  State mixing zone dimensions are
 designed to  limit  the impact of a mixing zone
 on the water body. Furthermore,  EPA's review
 of State  waste load allocations (WLAs) should
 evaluate whether  assumptions of complete or
 incomplete  mixing are  appropriate   based  on
 available data.

 In river systems, reservoirs, lakes, estuaries, and
 coastal  waters, zones of passage  are defined as
 continuous water  routes  of such  volume,  area,
 and   quality   as   to   allow   passage   of
 free-swimming and drifting organisms  so that no
 significant   effects   are  produced   on   their
 populations.     Transport   of  a  variety  of
 organisms   in  river  water  and   by   tidal
 movements in estuaries is biologically important
 for a number of reasons:

 •  food is carried  to the sessile  filter feeders
   and other nonmotile  organisms;

 •  spatial  distribution   of   organisms    and
   reinforcement of weakened populations are
   enhanced; and

 •  embryos  and larvae   of some  fish species
   develop while drifting.

 Anadromous  and catadromous species must be
 able to  reach suitable spawning  areas.   Their
 young (and in some  cases the adults) must be
 assured  a return  route  to  their  growing  and
 living areas.  Many species make  migrations for
 spawning  and  other  purposes.    Barriers  or
blocks that prevent  or interfere with these types
of essential  transport and  movement can  be
   Size

 Various  methods and  techniques  for defining
 the surface area and volume of mixing zones for
 various types of waters have been formulated.
 Methods  that  result in quantitative   measures
 sufficient for permit actions  and  that  protect
 designated uses of a water body as a whole are
 acceptable.     The  area   or  volume  of an
 individual  zone  or group  of zones  must be
 limited  to  an  area or volume as  small as
 practicable  that  will  not  interfere   with  the
 designated   uses  or   with   the  established
 community  of aquatic  life  in the  segment  for
 which the uses are designated.

 To ensure  that mixing  zones  do not impair the
 integrity  of the  water body,  it  should  be
 determined  that the mixing zone will not cause
 lethality   to  passing   organisms   and  that,
 considering  likely pathways   of exposure,  no
 significant human health risks exist. One means
 to achieve these objectives is to limit the size of
 the area affected  by the mixing zones.

 In the general  case, where  a State  has  both
 acute and chronic aquatic life criteria, as well as
 human   health    criteria,   independently
 established   mixing zone  specifications   may
 apply to each of the  three types of criteria.  For
 application of two-number aquatic  life criteria,
 there may be up  to two types of mixing zones
 (see Figure  5-1).  In   the  zone immediately
 surrounding the  outfall, neither the  acute nor
 the chronic criteria are  met.  The acute  criteria
 are met  at the edge of this  zone.  In the next
 mixing zone,  the  acute,  but not the  chronic,
 criteria  are met.   The chronic criteria  are met
 at the  edge of the  second  mixing zone.   The
acute mixing zone  may be  sized to  prevent
 lethality  to  passing organisms,  the  chronic
mixing zone sized to protect  the ecology of the
water body as a whole, and the  health criteria
mixing zone sized to prevent significant human
risks.  For any  particular pollutant  from any
(9/15/93)
                                                                                          5-3

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Water Quality Standards Handbook - Second Edition
                              Chronic criteria
                              (e.g., CCC) met
Figure 5-1. Diagram of the Two Parts of the
           Aquatic Life Mixing Zone
particular discharge,  the magnitude,  duration,
frequency, and mixing zone  associated  with
each of the three types of criteria  (acute  and
chronic aquatic life, and  human  health)  will
determine which one most limits the allowable
discharge.

Concentrations  above the chronic criteria are
likely to prevent sensitive  taxa from taking up
long-term residence  in the mixing zone. In this
regard,   benthic  organisms   and   territorial
organisms are  likely to be of greatest concern.
The higher the concentrations  occurring within
certain isopleths, the  more taxa are likely to be
excluded, thereby affecting  the structure  and
function of the ecological community. It is thus
important to  minimize the overall  size of the
mixing   zone   and  the   size  of  elevated
concentration  isopleths  within the mixing zone.

To determine  that, for aquatic  life protection, a
mixing zone is appropriately sized, water quality
conditions  within  the   mixing zone  may  be
compared to laboratory-measured  or predicted
toxicity benchmarks  as  follows:
•  It is not  necessary  to  meet chronic criteria
   within the mixing zone, only at the edge of
   the  mixing  zone.   Conditions  within the
   mixing zone would  thus not be adequate to
   assure survival, growth, and reproduction of
   all organisms that might  otherwise attempt
   to  reside continuously  within the  mixing
   zone.

•  If   acute   criteria   (criterion   maximum
   concentration,  or CMC, derived from 48- to
   96-hour exposure tests) are met throughout
   the  mixing zone, no lethality  should  result
   from temporary  passage  through the mixing
   zone.  If acute criteria are exceeded no more
   than a few minutes  in a parcel  of water
   leaving an outfall (as assumed in deriving
   the  section 5.1.2  options  for an  outfall
   velocity of 3 m/sec,  and  a size of 50 times
   the  discharge   length  scale),  this likewise
   assures no lethality  to  passing  organisms.

•  If  a full analysis  of concentrations   and
   hydraulic residence  times within the mixing
   zone  indicates   that   organisms  drifting
   through  the centerline  of the  plume  along
   the path of maximum exposure would not be
   exposed  to concentrations   exceeding  the
   acute criteria when averaged over  the 1-hour
   (or   appropriate    site-specific)   averaging
   period  for acute criteria, then lethality to
   swimming  or  drifting   organisms  should
   ordinarily not  be expected, even  for  rather
   fast-acting  toxicants.   In many  situations,
   travel time  through  the acute  mixing zone
   must be less than roughly 15 minutes  if a 1-
   hour average exposure is not to exceed the
   acute criterion.

   Where   mixing  zone   toxicity  is  evaluated
   using the probit  approach described  in the
   water   quality  criteria   "Blue    Book"
   (NAS/NAE,   1973),  or  using  models  of
   toxicant   accumulation   and   action   in
   organisms  (such  as described  by Mancini,
   1983,  or  Erickson   et   al.,  1989),  the
   phenomenon  of delayed mortality should be
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                                                                        Chapter 5 - General Policies
   taken into account before judging the mixing
   zone concentrations  to be safe.

The above  recommendations  assume  that  the
effluent  is repulsive, such that  free-swimming
organisms would avoid the mixing zones.  While
most  toxic  effluents are  repulsive,  caution is
necessary in evaluating attractive mixing zones
of known effluent  toxicity, and  denial of such
mixing zones may well be  appropriate.   It is
also important   to  assure that  concentration
isopleths within  any plume  will not extend to
restrict passage  of swimming organisms  into
tributary streams.

In all cases, the size of the mixing zone and  the
area  within  certain  concentration   isopleths
should  be  evaluated  for their  effect  on  the
overall biological integrity of the water body. If
the    total    area   affected    by    elevated
concentrations    within   all   mixing  zones
combined is small compared with the total area
of a water body (such as a river  segment), then
mixing zones  are likely to have  little effect on
the integrity  of the water  body  as a whole,
provided that  they do not impinge on unique or
critical  habitats.    EPA   has   developed   a
multistep  procedure  for evaluating the overall
acceptability of mixing zones (Brungs, 1986).

   Shape

The shape  of a mixing zone  should be a simple
configuration  that is easy to locate in a body of
water   and   that   avoids  impingement   on
biologically important areas.   In lakes, a circle
with a specified radius is generally preferable,
but other  shapes may be specified in the case of
unusual site requirements.   Most States  allow
mixing  zones  as  a policy  issue  but provide
spatial dimensions  to  limit the areal  extent  of
the mixing  zones.  The mixing zones are then
allowed  (or not  allowed)  after  case-by-case
determinations.   State  regulations  dealing with
streams and rivers generally  limit mixing zone
widths, cross-sectional  areas, and flow volumes,
and  allow  lengths  to  be  determined   on  a
case-by-case basis.  For lakes,  estuaries,  and
coastal waters, dimensions are usually specified
by surface area, width, cross-sectional  area, and
volume.    "Shore-hugging" plumes should  be
avoided in all water bodies.

   Outfall Design

Before designating any mixing zone,  the  State
should  ensure  that    the   best   practicable
engineering design is used and that the location
of the existing or  proposed  outfall  will  avoid
significant adverse  aquatic  resource  and water
quality impacts of the wastewater  discharge.

   In-Zone Quality

Mixing  zones  are  areas  where  an  effluent
discharge   undergoes  initial  dilution and  are
extended  to cover the  secondary  mixing in  the
ambient   water  body.   A  mixing zone  is an
allocated  impact  zone where acute and chronic
water quality  criteria can  be exceeded as long
as a  number  of  protections  are maintained,
including  freedom from the following:

(1)   materials   in concentrations   that  will
      cause acutely toxic conditions  to aquatic
      life;

(2)   materials in concentrations  that settle  to
      form objectionable deposits;

(3)   floating  debris,   oil,  scum,  and  other
      material   in  concentrations  that   form
      nuisances;
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(4)   substances in concentrations that produce
      objectionable   color,   odor,   taste,  or
      turbidity; and

(5)   substances in concentrations that produce
      undesirable  aquatic  life  or result  in a
      dominance  of nuisance species.

Acutely  toxic conditions are defined as those
lethal  to  aquatic  organisms  that   may  pass
through  the  mixing  zone.   As  discussed  in
section  5.1.2below, the underlying assumption
for allowing a mixing zone is that a small area
of concentrations in excess of acute and chronic
criteria   but  below  acutely toxic  releases  can
exist  without causing adverse  effects  to the
overall   water  body.   The   State   regulatory
agency  can decide to allow  or deny a  mixing
zone on a site-specific basis.  For a mixing zone
to be permitted, the discharger should prove to
the  State   regulatory  agency  that  all  State
requirements  for a mixing zone are met.

5.1.2 Prevention  of  Lethality  to Passing
      Organisms

Lethality is a  function  of  the  magnitude  of
pollutant concentrations  and the duration  an
organism is exposed  to those  concentrations.
Requirements for wastewater plumes that tend
to  attract  aquatic   life   should   incorporate
measures  to  reduce  the  toxicity  (e.g., via
pretreatment,  dilution) to minimize  lethality or
any irreversible toxic effects  on aquatic  life.

EPA's water  quality criteria  provide  guidance
on  the   magnitude  and duration  of pollutant
concentrations  causing lethality.  The CMC  is
used  as a  means  to  prevent  lethality or other
acute effects.  As explained  in  Appendix  D to
the  Technical  Support  Document  for  Water
Quality-based Toxics Control (USEPA,  1991a),
the CMC is a toxicity level and should  not be
confused with  an  LC50 level.   The CMC  is
defined  as one-half  of the  final acute value
(FAV)   for  specific   toxicants  and  0.3 acute
toxicity unit (TUJ for effluent toxicity (USEPA,
1991a,  chap. 2).   The  CMC  describes  the
condition under which lethality will not occur if
the duration of the exposure to the CMC level
is  less   than  1   hour.     The   CMC   for
whole-effluent toxicity  is intended  to prevent
lethality  or acute  effects in the  aquatic  biota.
The  CMC for  individual  toxicants  prevents
acute effects  in all but  a  small  percentage of
the tested  species.  Thus, the areal extent and
concentration  isopleths of the mixing zone must
be  such  that  the  1-hour average  exposure of
organisms  passing through  the  mixing zone is
less than the CMC. The organism must be able
to  pass  through   quickly  or flee the   high-
concentration   area.   The  objective  of mixing
zone  water  quality  recommendations   is to
provide  time-exposure  histories  that produce
negligible   or  no   measurable   effects   on
populations of critical species in the  receiving
system.

Lethality to passing organisms can be prevented
in the mixing zone in one  of four ways.  The
first method  is to prohibit  concentrations  in
excess of  the  CMC in  the pipe   itself, as
measured directly at the  end of the pipe.  As an
example,  the  CMC should  be met in the pipe
whenever a continuous discharge is made  to an
intermittent stream.  The second  approach is to
require  that  the  CMC  be met  within  a very
short distance from the  outfall  during chronic
design flow conditions for receiving waters (see
section 5.2, this Handbook).

If the second alternative  is selected,  hydraulic
investigations and  calculations indicate that  the
use of a high-velocity discharge  with  an  initial
velocity of 3 m/sec, or greater, together with a
mixing zone spatial  limitation of 50 times  the
discharge length scale in any direction,  should
ensure  that  the  CMC  is  met  within a  few
minutes  under practically all conditions.

The discharge  length scale is defined  as  the
square root of the cross-sectional  area of  any
discharge pipe.

A third  alternative  (applicable  to any  water
body)  is not  to use a high-velocity  discharge.
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                                                                          Chapter 5 - General Policies
 Rather  the discharger should  provide data to
 the State  regulatory  agency showing that the
 most  restrictive of the following conditions are
 met for each outfall:

 •  The  CMC should be met within 10 percent
    of the distance  from the edge of the outfall
    structure  to  the  edge  of the  regulatory
    mixing zone in any spatial direction.

 •  The  CMC should be met within a distance
    of 50 times  the discharge length scale in any
    spatial direction.  In the case of a multiport
    diffuser, this requirement must be  met for
    each  port using the appropriate  discharge
    length scale of that port.   This restriction
    will ensure  a dilution  factor of at least  10
    within  this  distance   under   all  possible
    circumstances, including  situations of severe
    bottom  interaction,  surface interaction,  or
    lateral merging.

 •  The CMC should be met within a distance
    of  5  times  the  local  water depth  in any
    horizontal   direction  from  any  discharge
    outlet.   The local water depth is defined  as
    the natural water depth (existing prior to the
    installation    of   the    discharge   outlet)
    prevailing   under   mixing-zone   design
    conditions (e.g., low-flow for rivers).   This
    restriction will prevent locating the discharge
    in very shallow environments  or very close to
    shore,  which  would  result  in  significant
    surface and  bottom  concentrations.

A fourth  alternative  (applicable to  any water
body)  is  for the discharger  to provide data  to
the  State  regulatory  agency  showing  that  a
drifting organism would not be exposed  to  1-
hour   average  concentrations   exceeding  the
CMC, or would not receive harmful  exposure
when  evaluated  by other   valid  toxicological
analysis  (USEPA,  1991a, chap.  2).   Such data
should  be  collected   during  environmental
conditions that  replicate critical conditions.

For the third and fourth alternatives, examples
of such data include monitoring  studies, except
 for those situations  where collecting  chemical
 samples  to  develop  monitoring  data would be
 impractical, such as  at deep outfalls in oceans,
 lakes,  or embayments.    Other  types  of data
 could  include  field  tracer  studies  using dye,
 current  meters,  other  tracer   materials,  or
 detailed   analytical    calculations,   such  as
 modeling  estimations  of  concentration   or
 dilution  isopleths.

 The  following outlines a method, applicable to
 the fourth alternative,  to  determine  whether a
 mixing zone is tolerable for a free-swimming or
 drifting  organism.    The  method  incorporates
 mortality rates (based on toxicity studies  for the
 pollutant  of  concern  and  a  representative
 organism)   along    with   the   concentration
 isopleths of the  mixing zone and the length of
 time the organism  may spend  in each  isopleth.
 The  intent  of the method  is to prevent  the
 actual  time of  exposure  from  exceeding  the
 exposure time required to elicit an effect:
                      T(n)
                 ET\X) at C.
 where T(n) is the exposure  time an organism is
 in isopleth n, and  ET(X) is the "effect time."
 That is, ET(X)  is the exposure time required  to
 produce an effect (including a delayed effect) in
 X   percent   of   organisms   exposed   to  a
 concentration equal to C(n), the concentration  in
 isopleth   n.     ET(X)    is    experimentally
 determined;  the effect  is usually mortality.  If
 the  summation  of  ratios of exposure time  to
 effect time  is  less than  1, then  the percent
 effect will not occur.

 5.1.3 Human Health Protection

 For protection of human health, the presence  of
 mixing  zones should  not result in  significant
 health risks when evaluated  using reasonable
 assumptions  about  exposure pathways.   Thus,
 where  drinking  water  contaminants  are  a
concern, mixing zones  should not encroach on
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drinking  water intakes.    Where  fish  tissue
residues   are  a  concern  (either  because  of
measured  or predicted  residues),  mixing zones
should not be projected to result in significant
health  risks to average consumers  of fish and
shellfish, after considering  exposure duration of
the affected  aquatic  organisms  in the mixing
zone and the patterns  of fisheries use in the
area.

While  fish tissue contamination  tends to be a
far-field problem affecting  entire water bodies
rather  than a narrow-scale  problem  confined to
mixing zones, restricting or eliminating mixing
zones  for bioaccumulative  pollutants  may be
appropriate   under   conditions  such as  the
following:

•  Mixing zones should be restricted  such that
   they do not encroach on areas often used for
   fish harvesting  particularly  of stationary
   species such as shellfish.

•  Mixing zones  might be  denied  (see section
   5.1.4) where such  denial is used as a device
   to   compensate   for uncertainties   in  the
   protectiveness  of the water quality criteria or
   uncertainties  in the  assimilative capacity of
   the  water body.
5.1.4 Where   Mixing   Zones   Are   Not
      Appropriate

States  are  not  required  to allow mixing zones
and,  if  mixing  zones  are  allowed,  a  State
regulatory  agency may decide to deny a mixing
zone   in  a   site-specific   case.     Careful
consideration    must    be   given   to    the
appropriateness   of a mixing  zone  where  a
substance   discharged   is   bioaccumulative,
persistent,  carcinogenic,   mutagenic,    or
teratogenic.

Denial    should   be    considered   when
bioaccumulative pollutants are in the discharge.
The potential  for a pollutant  to bioaccumulate
in living organisms is  measured  by:

•  the bioconcentration  factor (BCF),  which is
   chemical-specific and describes the degree to
   which an  organism or tissue can acquire a
   higher  contaminant  concentration  than  its
   environment  (e.g.,surface water);

•  the duration  of exposure; and

•  the concentration of the chemical of interest.

While any BCF value greater than 1 indicates
that   bioaccumulation   potential   exists,
bioaccumulation   potential  is  generally   not
considered  to  be  significant unless  the  BCF
exceeds  100 or more.  Thus, a chemical that is
discharged to  a receiving  stream resulting in
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                                                                          Chapter 5 - General Policies
 low concentrations  and  has a low BCF value
 will not  result in  a  bioaccumulation   hazard.
 Conversely,  a chemical that is discharged  to  a
 receiving    stream    resulting    in   a   low
 concentration  but having a high BCF value  may
 result  in a bioaccumulation  hazard.  Also, some
 chemicals of relatively low toxicity, such as zinc,
 will bioconcentrate   in  fish  without  harmful
 effects resulting from human  consumption.

 Factors  such  as size of  zone,  concentration
 gradient  within the zone, physical habitat,  and
 attraction  of aquatic  life are  important in this
 evaluation.  Where unsafe  fish tissue levels or
 other  evidence indicates a lack of assimilative
 capacity  in   a particular   water  body  for   a
 bioaccumulative pollutant,  care should be taken
 in calculating discharge limits for this pollutant
 or the additivity of multiple pollutants.   In such
 instances,  the ecological  or  human  health
 effects may be so adverse that a mixing zone is
 not appropriate.

 Another  example of when a regulator should
 consider   prohibiting   a  mixing   zone  is in
 situations  where an effluent is known to attract
 biota.  In  such cases,  provision of a continuous
 zone of passage around the  mixing area will not
 serve the purpose of protecting aquatic  life. A
 review   of    the   technical    literature    on
 avoidance/attraction  behavior revealed that the
 majority  of  toxicants  elicited  an  avoidance or
 neutral response at  low concentrations  (Versar,
 1984).  However, some chemicals did  elicit an
 attractive  response,  but the  data  were  not
 sufficient  to  support  any  predictive methods.
 Temperature   can  be an attractive  force  and
 may  counter   an   avoidance   response  to  a
pollutant,  resulting  in attraction  to the  toxicant
discharge.  Innate  behavior such  as migration
may also  supersede  an avoidance response  and
cause a fish  to incur a significant  exposure.

5.1.5 Mixing  Zones  for  the  Discharge  of
      Dredged or Fill Material

EPA,  in  conjunction  with the Department  of
the Army,  has developed guidelines  to be
applied in evaluating the discharge of dredged
or fill material in navigable  waters  (see 40 CFR
230).   The  guidelines  include  provisions  for
determining    the   acceptability    of  mixing
discharge  zones  (section   230.11(f)).    The
particular    pollutant   involved   should   be
evaluated  carefully in  establishing  dredging
mixing  zones.    Dredged   spoil   discharges
generally  result   in   temporary    short-term
disruption and  do  not represent  continuous
discharge that will affect beneficial  uses over a
long term. Disruption of beneficial  uses should
be  the primary  consideration  in establishing
mixing zones for dredge and fill activities.  State
water  quality  standards  should  reflect   these
principles if mixing zones for dredging activities
are referenced.

5.1.6 Mixing  Zones for Aquaculture Projects

The Administrator  is authorized,  after public
hearings, to permit certain discharges associated
with approved  aquaculture projects (section 318
of  the  Act).    The regulations   relating  to
aquaculture   (40  CFR  122.56  and  125.11)
provide that the  aquaculture  project area and
project  approval   must  not  result  in  the
enlargement  of any previously approved mixing
zone.   In   addition,  aquaculture   regulations
provide that  designated  project areas must not
include so large  a portion of the body of water
that a  substantial  portion  of the  indigenous
biota will be exposed to conditions  within the
designated  projects  area  (section  125.11(d)).
Areas  designated   for  approved  aquaculture
projects should be treated in  the same manner
as  other  mixing zones.   Special  allowances
should not be  made for these areas.
         Critical Low-Flows
Water quality standards should  protect  water
quality for designated  uses  in critical low-flow
situations.     In  establishing   water   quality
standards,  States  may  designate  a critical low-
flow  below   which  numerical   water  quality
criteria do not apply.  At all times, waters shall
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be  free  from  substances  that  settle  to form
objectionable deposits; float as debris, scum, oil,
or other matter;  produce  objectionable  color,
odor, taste,  or turbidity;  cause acutely toxic
conditions; or produce undesirable  or nuisance
aquatic  life.

To   do  steady-state  waste  load  allocation
analyses, these low-flow values  become design
flows for sizing  treatment  plants,  developing
waste load  allocations,  and developing  water
quality-based effluent limits. Historically, these
so-called  "design" flows were selected for the
purposes of waste load allocation analyses that
focused   on  instream    dissolved   oxygen
concentrations  and protection  of aquatic life.
EPA introduced hydrologically and biologically
based analyses  for the protection of aquatic life
and human  health  with the publication of the
Technical Support Document for Water Quality-
based  Toxics Control.   These  concepts have
been   expanded   subsequently   in   guidance
entitled   Technical   Guidance  Manual  for
Performing   Wasteload  Allocations,   Book  6,
Design Conditions, (USEPA, 1986c). These new
developments are included in Appendix D of
the 1991 Technical Support Document for Water
Quality-based Toxics Control (USEPA, 1991a).
The discussion here  is greatly  simplified; it is
provided to support EPA's recommendation  for
baseline  application  values for instream  flows
and thereby maintain the intended stringency of
the criteria  for priority toxic  pollutants.  EPA
recommended  either  of  two  methods  for
calculating acceptable  low-flows, the traditional
hydrologic  method   developed  by  the  U.S.
Geological  Survey  and  a biologically  based
method developed  by EPA.

Most States have  adopted   specific  low-flow
requirements for streams and rivers to protect
designated  uses  against  the  effects of toxics.
Generally, these  have followed  the guidance in
the TSD.   EPA  believes  it is essential that
States   adopt  design  flows  for  steady-state
analyses  so that  criteria are implemented
appropriately.  The  TSD also recommends  the
use of three  dynamic models  to perform  waste
load allocations.  Because dynamic waste load
models  do  not  generally  use specific  steady-
state  design flows but  accomplish  the same
effect  by   factoring   in  the  probability  of
occurrence  of  stream  flows  based  on  the
historical    flow   record,   only   steady-state
conditions  will be discussed  here.   Clearly, if
the criteria  are implemented  using inadequate
design flows, the resulting toxics controls would
not be  fully  effective  because  the  resulting
ambient  concentrations  would exceed  EPA's
criteria.

In  the  case of  aquatic life, more  frequent
violations than the assumed exceedences  once
in 3 years would result in diminished vitality of
stream ecosystems characteristics by the loss of
desired  species  such as sport fish.  Numeric
water quality criteria should  apply at all flows
that are equal to or greater  than flows specified
in Exhibit 5-1.

EPA is recommending the harmonic  mean flow
to be applied with  human health  criteria for
carcinogens.  The  concept of a harmonic mean
is a standard statistical data analysis technique.
EPA's model for human  health effects assumes
that such effects occur because of a long-term
exposure  to  low  concentration   of  a  toxic
pollutant   (for example, 2 liters  of water per
day   for   70  years).     To   estimate   the
concentrations of the toxic  pollutant in  those 2
liters  per day by withdrawal from  streams with
a high daily variation in  flow, EPA believes the
harmonic  mean  flow is  the correct  statistic to
use in computing such design flows rather than
other  averaging  techniques.   For a description
of harmonic  means,  refer to Rossman (1990).
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                                                                          Chapter 5 - General Policies
                  AQUATIC LIFE

   Acute criteria (CMC)        1010 or 1B3

   Chronic criteria (CCC)      7010 or «B3
   Non-carcinogens

   Carcinogens

   Where:
HUMAN HEALTH

          30Q5

          Harmonic
flow
   1010  is  the lowest  one day flow  with an average
      recurrence frequency of once in 10 years determined
      hydrologically;

   183 is biologically based and indicates an allowable
      exceedence of once every 3 years. It is determined
      by EPA's computerized method 
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Variance   procedures    involve   the    same
substantive  and  procedural  requirements  as
removing a designated use (see  section 2.7, this
Handbook), but unlike use removal,  variances
are both discharger and pollutant  specific, are
time-limited,  and  do not forego the  currently
designated use.

A variance should  be used instead  of removal
of a use where the State  believes the standard
can ultimately be attained.  By maintaining the
standard rather than  changing it, the  State will
assure  that   further  progress   is   made  in
improving water   quality  and  attaining  the
standard.   With  a variance,  NPDES permits
may be written such that reasonable progress is
made  toward  attaining  the  standards without
violating  section  402(a)(l)  of  the  Act,  which
requires  that  NPDES permits  must  meet the
applicable  water quality standards.

State  variance procedures,   as  part  of  State
water quality standards, must  be consistent with
the substantive requirements  of 40 CFR  131.
EPA has approved State-adopted  variances in
the past  and  will continue to  do so if:

•  each individual  variance is included as part
   of the  water quality standard;

•  the  State   demonstrates   that meeting the
   standard is unattainable   based  on one or
   more of the grounds outlined  in 40 CFR
   131.10(g) for removing a designated use;

•  the justification submitted by the State
   includes  documentation   that treatment
   more  advanced  than that  required   by
   sections 303(c)(2)(A)  and (B)  has been
   carefully considered,  and that alternative
   effluent  control  strategies   have  been
   evaluated;

•  the   more  stringent   State  criterion   is
   maintained  and  is binding  upon  all  other
   dischargers   on   the   stream   or  stream
   segment;
•  the  discharger  who is given a  variance  for
   one  particular   constituent   is  required   to
   meet   the   applicable   criteria   for  other
   constituents;

•  the  variance is granted  for a specific period
   of  time  and  must  be  rejustified  upon
   expiration but  at least every 3  years (Note:
   the  3-year limit is derived from  the triennial
   review requirements of section 303(c) of the
   Act.);

•  the  discharger either must meet  the standard
   upon  the  expiration of  this  time period  or
   must   make   a   new   demonstration    of
   "unattainability";

•  reasonable  progress is being made  toward
   meeting the standards;  and

•  the  variance was subjected to public notice,
   opportunity   for   comment,    and   public
   hearing.  (See section 303(c)(l)  and 40 CFR
   131.20.) The public notice should contain  a
   clear   description   of the  impact   of  the
   variance  upon  achieving  water   quality
   standards  in the affected stream segment.
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                            Chapter 6 - Procedures for Review and Revision of Water Quality Standards
                                CHAPTER 6

                      PROCEDURES FOR REVIEW
                            AND REVISION OF
                     WATER QUALITY STANDARDS

                         (40 CFR 131 - Subpart C)


                              Table of Contents
6.1 State Review and Revision  	6-1
    6.1.1     Consultation with EPA	  6-1
    6.1.2     Public Notice Soliciting Suggestions for Additions or Revisions to
             Standards   	6-1
    6.1.3     Review of General Provisions   	6-3
    6.1.4     Selection of Specific Water Bodies for Review	6-3
    6.1.5     Evaluation of Designated Uses	6-4
    6.1.6     Evaluation of Criteria	6-6
    6.1.7     Draft Water Quality Standards Submitted to EPA for Review	6-7
    6.1.8     Public Hearing on Proposed Changes to Standards  	6-7
    6.1,9     State Adopts Revisions; Submits Standards  Package to EPA for Review  ..  6-7

6.2 EPA Review and Approval	6-8
    6.2.1     Policies and Procedures Related to Approvals  	6-11
    6.2.2     Policies and Procedures Related to Disapprovals	 6-11
    6.2.3     Policies and Procedures Related to Conditional Approvals   	 6-12

6.3 EPA Promulgation	6-13

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                                  Chapter 6 - Procedures for Review and Revision of Water Quality Standards
                                       CHAPTER 6
            PROCEDURES FOR REVIEW AND REVISION OF WATER
                                 QUALITY STANDARDS
State  review  and  revision  of  water quality
standards  are discussed  in section 6.1. of this
chapter.     Guidance   is  provided  on   the
administrative and regulatory requirements  and
procedures that  should be followed in the State
review and submittal  process as  well as  the
implication  of  a  State's  failure  to submit
standards.     EPA   review  and   approval
procedures are discussed in section 6.2, and  the
procedures   for  promulgation   of  Federal
standards  are  described in section  6.3.
          State Review and Revision
Section  303(c)(l)  of the  Clean  Water  Act
requires  that a State shall, from time to time,
but  at least  once  every  3 years,  hold  public
hearings  to  review applicable  water quality
standards and, as appropriate,  to  modify and
adopt  standards.     The  3-year  period  is
measured from the date of the  letter  in which
the  State informs  EPA  that revised or  new
standards have been adopted for the affected
waters and are being submitted for EPA review
or, if no changes were made in the  standards
for those waters,  from the date  of  the letter  in
which the State informs EPA that the standards
were reviewed and  no changes were made.

States  identify additions  or revisions  necessary
to  existing  standards  based  on their 305(b)
reports,   other    available    water   quality
monitoring   data,   previous   water   quality
standards reviews,  or requests  from  industry,
environmental  groups,  or the public.  Water
quality standards  reviews and  revisions  may
take many forms,  including additions  to  and
modifications  in   uses,  in   criteria,   in  the
antidegradation  policy, in the antidegradation
implementation procedures, or in other general
policies.

6.1.1    Consultation with EPA

State consultation  with EPA  regional offices
should occur when States  begin  activities  to
revise or adopt new water quality standards and
long before  the  State  standards  are  formally
submitted for EPA review. Reasons  for early
consultation  with EPA  include the following:

•    States will benefit from early identification
     of potential areas of disagreement  between
     EPA  and  the   States,   and  EPA  can
     determine   where   assistance   may  be
     provided;

•    EPA must be  in a position to respond  to
     litigation and  to  congressional and  other
     inquiries relating  to actions on the revised
     State water quality standards;

•    Headquarters  must  be ready to  support
     promulgation actions when State standards
     have been disapproved;

•    early consultation  with EPA  allows issues
     to  be  discussed   well  before a formal
     review request is received from the State;
     and

•    EPA actions  related to  State standards
     should receive as comprehensive  a review
     as possible.

6.1.2  Public Notice Soliciting Suggestions for
       Additions or Revisions to Standards

An important component of the water quality
standards   setting  and  review process  is  a
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Water Quality Standards Handbook - Second Edition
               Consultation with EPA
               Public Notice Soliciting
              Suggestions for Additions
              or Revisions to Standards
             Review of General Provisions
           Appropriate Use Designations
             (Chapter 2)
           Criteria review and Development
             (Chapters)
           Antidegradation Policy
           Implementation (Chapter 4)
           Downgrade/Variance Provisions
             (Section 5.3)
           Inclusion of All Waters of the U.S.
             (Section 1.3)
           Low Flow Provisions (Section 5.2)
           Mixing Zone Provisions (Section 5.1)
           Definitions
           Other
                Selection of Specific
               Waterbodies for Review
             CWA§305(b) Report
             CWA §304(1) List
             CWA §303(d) Waters
             CWA §319 Waters
             Construction Grants Priority List
             Expired Major Permits
             Waters Not Meeting CWA
             §101 (a)(8) Goals
             Unclassified Waterbodies
             Public Input
            Evaluation of Designated Uses
                    (Chapter 2)
                Evaluation of Criteria
                    (Chapters)
  Draft Water Quality
Standards Submitted to
    EPA for Review
   Public Hearing on
 Proposed Changes to
Water Quality Standards
State Adopts Revisions I
i
r
 State Attorney General
 Certifies Water Quality
      Standards
State Submits Revisions,
 Methods, Justifications
 and Attorney General
 Certification to EPA for
       Review
      /  EPA
      Approves
      Standards
     (Section 6.2)
No
                                             Yes
         State Proposes Revisions
                                                                                                   No
                                 EPA Promulgates Federal
                                 Water Quality Standards
                                       (Section 6.3)
  Standards to Permits
       Process
  Figure 6-1.  Simplified Flow Chart of a Typical State Water Quality Standards Review Process
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                                    Chapter 6 - Procedures for Review and Revision of Water Quality Standards
 meaningful involvement of those affected by the
 standards  decisions.   At  a minimum,  section
 303 (c)  of the Clean Water Act requires States
 to  hold  a  public  hearing  in reviewing  and
 revising water quality standards. (State law may
 require  more  than one hearing.)    However,
 States  are  urged  to involve the public  more
 actively in the  review process.  Involvement  of
 the public includes the involvement  of citizens
 affected by  standards  decisions,  the  regulated
 community  (municipalities  and  industry), and
 inter-governmental   coordination  with  local,
 State, and Federal  agencies, and  Indian Tribes
 with  an interest in water  quality issues.   This
 partnership  will ensure the  sharing  of ideas,
 data, and  information,  which will increase  the
 effectiveness    of   the   total   water  quality
 management  process.

 Public  involvement  is beneficial  at  several
 points in the water quality standards  decision
 making  process.    Enlisting   the support  of
 municipalities,   industries,   environmentalists,
 universities,  other  agencies,  and the affected
 public in collecting and evaluating information
 for the decision making process  should assist
 the State in improving  the scientific  basis for,
 and in building  support  for, standards  decisions.
 The more that  people and groups are involved
 early  in  the  process   of  setting  appropriate
 standards,  the more support the State will have
 in implementing the standards.

 6.1.3  Review of General Provisions

 In each  3-year water quality  standards  review
 cycle, States  review the general  provisions  of
 the   standards   for  adequacy   taking   into
 consideration:

 •    new Federal or State statutes, regulations,
     or guidance;

 •    legal  decisions involving  application   of
     standards;  or

•    other  necessary clarifications or  revisions.
     Inclusion  of All  Waters of the United
     States

Water  quality  standards  are  needed  for all
"waters of the  United  States,"  defined  in the
National   Pollution   Discharge   Elimination
System Regulations at 40 CFR  122.2 to include
all interstate waters, including wetlands, and all
intrastate   lakes,  rivers,  streams   (including
intermittent  streams),  wetlands, natural ponds,
etc.,  the   use,  degradation   or destruction  of
which would affect or could  affect interstate or
foreign commerce.   The term "waters of the
United States"  should be read  broadly during
the  standards  review process.   States should
ensure that all  waters under this definition are
included in the States' water quality  standards,
are   assigned   designated   uses,  and   have
protective  criteria.

    Definitions

Terms used in  the  Water   Quality  Standards
Regulation are  defined in 40 CFR 131.3.  The
glossary  of this  document contains  these  and
other  water  quality  standards-related   terms
defined  by  the  Clean  Water  Act,   EPA
regulation, or guidance. States,  when reviewing
their   water quality  standards,  should   at  a
minimum  define  those terms  included in the
Definitions section  of the  regulation to  be
synonymous with the  EPA definitions.

6.1.4  Selection of Specific Water Bodies  for
       Review

The Water Quality Standards Regulation allows
States  to  establish  procedures  for identifying
and reviewing  the standards  on specific  water
bodies  in  detail.    Any  procedures  States
establish   to   revise   standards   should   be
articulated  in the  continuing  planning process
consistent  with  the water quality  management
regulation.   Water bodies receiving a  detailed
standards   review  are most  likely to  be  those
where:
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Water Quality Standards Handbook - Second Edition
•  combined  sewer  overflow  (CSO)  funding
   decisions  are pending;

•  water quality-based permits are scheduled  to
   be issued or reissued;

•  CWA goal uses are not being met;

•  toxics   have   been   identified  and  are
   suspected of precluding  a  use or may be
   posing  an  unreasonable   risk to  human
   health;  or

«  there   may   be   potential    impacts   on
   threatened or endangered species.

States  may have other  reasons  for wishing  to
examine a  water body in detail, such as human
health   problems,   court orders,  or  costs  or
economic and  social impacts of  implementing
the existing  water  quality  standards.    States
must reexamine any water body with standards
not consistent with the  section  101(a)(2)  goals
of the Act every 3 years, and if new information
indicates that section 101(a)(2)  goal uses are
attainable,  revise  its standards  to reflect  those
uses.

States are encouraged to review standards for a
large  enough area to consider the interaction
between  both  point   and   nonpoint   source
discharges.   In carrying out standards  reviews,
the States  and  EPA   should  ensure  proper
coordination  of all water quality  programs.
6.1.5  Evaluation of Designated Uses

Once priority water bodies have been selected
for  review,   the  designated   uses  must   be
evaluated.  This may involve some level of data
collection up to and including a full water body
survey and  assessment;  however, an intensive
survey of the  water body is  not necessary  if
adequate  data are available.   The purpose of
the evaluation is to pinpoint problems and to
characterize present uses, attainable uses (uses
that could exist in the absence of anthropogenic
effects),  uses  impaired  or precluded, and  the
reasons  why uses are  impaired  or precluded.
Information generated in the survey also can be
used to establish the basis for seasonal uses  and
subcategories  of uses.

Included in section 2.9 of this Handbook  are
examples of a range of physical, chemical,  and
biological characteristics  of the water body that
may  be  surveyed  when  evaluating  aquatic
protection  uses.  This information is then used
in determining the existing species in the water
body and the  health of those species, as well as
what  species could be in the water body given
the physical characteristics of the water body, or
what species might be in the water if the quality
of the water were improved.

   Review of the Cause of Uses Not Being Met

If the survey indicates that designated uses are
impaired,  the next step  is to determine  the
cause.  In  many situations, physical conditions
and/or  the presence of pollutants  prevent  the
water  body from meeting its  designated   use.
Physical limitations  refer to  such factors as
depth, flow, habitat, turbulence, or  structures
such as dams  that might  make  a use unsuitable
or  impossible  to  achieve  regardless  of  water
quality.

If  uses  are  precluded   because  of  physical
limitations  of the  water  body, the State  may
wish to examine modifications  that might allow
a habitat suitable  for a  species  to thrive where
it  could not before.  Some of the techniques
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                                   Chapter 6 - Procedures for Review and Revision of Water Quality Standards
which   have   been   used   include   bank
stabilization, current deflectors, construction of
oxbows, or installation  of spawning beds.  A
State also might wish to consider  improving the
access to the  water body, improving facilities
nearby  so that  it  can be used  for  recreational
purposes,  or  establishing  seasonal  uses  or
subcategories  of a use.

If uses are  not being  met because of water
pollution  problems, the  first step  in the process
is to determine  the cause.   If  the  standards
review process is well coordinated with the total
maximum  daily load (TMDL)   determination
and   the  permit  process,  permitees  may  be
required  to  conduct  some  of the  analyses
necessary  to  determine   why  uses  are  not
attained  (For more information on the TMDL
process,  see chapter 7,  this Handbook.) When
background levels  of pollutants are irreversible
and   criteria  cannot  be  met,   States   should
evaluate other more appropriate  uses and revise
the water quality standards  appropriately.

   Determination  of Attainable Uses

Consideration  of  the suitability  of the  water
body to attain a use is  an integral part of the
water quality  standards  review and  revision
process.   The data and information collected
from the water body survey provide a firm basis
for  evaluating  whether  the   water  body is
suitable  for  the   particular  use.   Suitability
depends   on   the   physical,   chemical,   and
biological characteristics  of the water body, its
geographic setting  and scenic qualities,  and the
socioeconomic  and  cultural  characteristics  of
the   surrounding   area.  Suitability  must   be
assessed  through the professional judgment of
the  evaluators.   It  is  their  task  to  provide
sufficient  information  to the  public  and  the
State decision  makers.

In some instances,  physical factors may preclude
the   attainment   of   uses   regardless    of
improvements  in the chemistry  of the receiving
water.  This  is particularly true  for fish and
wildlife protection   uses  where  the lack  of a
proper  substrate may preclude  certain forms of
aquatic   life  from   using  the   stream   for
propagation, or the lack of cover,  depth, flow,
pools, riffles, or impacts  from  channelization,
dams, or  diversions  may preclude  particular
forms  of   aquatic   life  from  the   stream
altogether.      While  physical  factors  may
influence    a   State's   decision    regarding
designation  of uses  for a water  body, States
need  to give consideration to the incidental uses
that  may   be  made   of the  water  body
notwithstanding  the   use designation.     For
example, even  though it may not make sense to
encourage  use  of  a  stream   for  swimming
because  of the flow, depth, or velocity of the
water, the States and EPA must recognize that
swimming and/or  wading may, in fact, occur.
To protect public health,  States  must set criteria
to reflect swimming if it  appears  that primary
contact  recreation   will, in fact, occur  in  the
stream.

While  physical  factors  are   important   in
evaluating whether a use  is attainable, physical
limitations   of  the  stream  may  not   be   an
overriding  factor.   Common  sense  and good
judgment  play an  important   role  in  setting
appropriate uses and criteria. In setting criteria
and uses, States must assure the attainment  of
downstream  standards.   The downstream  uses
may  not be affected  by the  same physical
limitations as the  upstream  uses.

If a change in  the  designated use is  warranted
based on a use attainability analysis, States may
modify the uses currently assigned.  In doing so,
the State  should  designate uses  that  can  be
supported   given  the  physical,  chemical,   or
biological limitations of the water body.  Or, a
State  may designate  uses on a seasonal  basis.
Seasonal  use designations  may  be  appropriate
for streams  that lack adequate  water  volume to
support aquatic life year round, but can be used
for fish  spawning,  etc., during  higher flow
periods.  In setting seasonal uses, care must be
taken  not  to allow the creation of conditions
instream that preclude uses in  another  season.
EPA  encourages  the designation   of seasonal
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Water Quality Standards Handbook - Second Edition
uses   as   an   alternative   to   completely
downgrading the use of a water body.

   Economic Impact Assessment

The Water Quality Standards  Regulation allows
States  to establish  uses that are inconsistent
with the section 101(a)(2) goals of the Act  if
the more stringent  technology required  to meet
the goals will cause substantial and widespread
economic and social impact.  These are  impacts
resulting  specifically  from  imposition   of  the
pollution  controls  and  reflect  such factors  as
unemployment,  plant  closures, and changes in
the  governmental   fiscal base.  The   analysis
should address  the incremental  effects of water
quality  standards  beyond technology-based  or
other State  requirements.   If the requirements
are not demonstrated  to have an incremental,
substantial,   and  widespread  impact   on  the
affected  community,  the  standard  must  be
maintained  or made compatible  with the goals
of the  Act.

6.1.6  Evaluation of Criteria

Changes  in use  designations   also  must  be
accompanied by consideration of the need  for
a change in criteria.   If a use is removed,  the
criteria to  protect  that use may be deleted  or
revised to  assure protection  of the remaining
uses.  If a use is added, there  must be adequate
water  quality   criteria   to   protect  the  use.
Regardless of whether changes or modifications
in uses are made, criteria protective of the  use
must be adopted.   Certain  criteria are deemed
essential for inclusion  in all State  standards,
and  criteria for section  307(a) toxic pollutants
must be  addressed   consistent  with  section
303(c)(2)(B)  (see  chapter  3, this Handbook).
All  State  standards  should  contain  the  "free
froms" narrative statements  (see  section  3.5.2)
in addition to numerical limits that can be used
as a basis for regulating  discharges into surface
waters.  Also, water quality parameters  such as
temperature,    dissolved   oxygen,  pH,    and
bacteriological  requirements  are basic  to  all
State standards.

EPA's  laboratory-derived   criteria   may  not
always  accurately  reflect   the   bioavailability
and/or  toxicity of a pollutant  because  of the
effect   of  local   physical   and   chemical
characteristics  or varying sensitivities of local
aquatic    communities.      Similarly,  certain
compounds may be more  or less toxic in some
waters because of differences  in temperature,
hardness,  or  other conditions.   Setting site-
specific criteria is appropriate where:

•  background water  quality parameters,  such
   as pH,  hardness, temperature,  color, appear
   to differ  significantly  from the  laboratory
   water used  in developing  the  section 304(a)
   criteria; or

•  the types of local  aquatic organisms  differ
   significantly from  those  actually  tested in
   developing  the  section 304(a) criteria.

Developing site-specific criteria is a method of
taking local  conditions  into account  so  that
criteria  are adequate  to protect the designated
use  without being  more or less  stringent than
needed.   A  three-phase  testing  program  that
includes  water quality sampling and analysis, a
biological  survey, and acute bioassays provides
an approach for developing site-specific criteria.
Much of the data and information for the water
quality sampling and analysis and the  biological
survey can be obtained  while conducting the
assessment  of the  water  body.   Included in
section  3.10 of this Handbook are scientifically
acceptable procedures   for  setting  site-specific
pollutant   concentrations    that   will  protect
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                                   Chapter 6 - Procedures for Review and Revision of Water Quality Standards
designated uses.  EPA believes that setting  site-
specific  criteria  will occur  on only a  limited
number  of stream  segments  because  of the
resources required to conduct  the  analyses and
the  basic soundness   of the  section  304(a)
recommendations.

6.1.7  Draft   Water    Quality   Standards
       Submitted to EPA for Review

While not a regulatory requirement, prudence
dictates that draft State water quality standards
be submitted  to  EPA  for review.  The  EPA
regional  office and  Headquarters   will conduct
concurrent reviews of draft standards and make
comments on proposed revisions  to assist the
State  in  producing   standards   that   are
approvable  by the  Regional  Administrator.
Continuing cooperation between the State and
EPA is  essential  to timely  approval of  State
standards.

6.1.8  Public Hearing on Proposed Changes to
       Standards

Before  removing  or  modifying   any   use or
changing criteria, the Clean Water  Act requires
the State  to hold  a public hearing. More than
one  hearing   may  be required depending  on
State regulations.    It  may  be appropriate  to
have EPA review  the adequacy of justifications
including   the  data  and  the  suitability  and
appropriateness  of  the analyses and how the
analyses   were  applied  prior  to  the  public
hearing.  In cases where the analyses are judged
to be  inadequate,  EPA  will identify how the
analyses  could  be improved and suggest the
additional  types of evaluations or data  needed.
By consulting with EPA frequently  throughout
the review process, States can be better assured
that  EPA  will be able to expeditiously review
State submissions and make the determination
that  the standards meet the requirements  of the
Act.

The  analyses  and supporting  documentation
prepared   in  conjunction   with  the proposed
water quality standards revision should be made
available  to  the  interested  public prior to the
hearing.    Open  discussion  of the  scientific
evidence   and  analysis   supporting  proposed
revisions  in  the water  quality   standards  will
assist the  State in making its decision.

6.1.9  State   Adopts   Revisions;   Submits
       Standards Package to EPA for Review

Within  30 days of their  final  administrative
action,  States  submit  to EPA  water  quality
standards   revisions,  supporting  analyses,  and
State Attorney  General  certification  that the
standards  were duly adopted  pursuant  to State
law.  Final administrative action  is meant to be
the  last  action  a State must take before  its
revision becomes a rule  under State law and it
can officially transmit State-adopted  standards
to EPA for review. This last action  might be a
signature,  a review by a legislative committee or
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State  Board, or a delay mandated  by a State
administrative procedures act.

In  reviewing   changes  in  uses   that   are
inconsistent  with the section  101 (a) (2) goals of
the Act  or changes   in  criteria,  EPA   will
carefully consider the adequacy  of the analyses
and the public comments  received  during  the
hearing process.   Standards  are  to meet  the
goals  of the Act unless the  State can  clearly
demonstrate that the uses reflected in the goals
are unattainable.
       EPA Review and Approval
When States adopt new or revised water quality
standards,  the  State  is  required  under CWA
Section  303(c) to submit such standards  to EPA
for review and approval/disapproval.   Section
131.20(c)  of  the  Water  Quality  Standards
Regulation requires the  submittal  to EPA  to
occur within  30 days of the final State action.
Figure 6.2 outlines EPA's review process.  EPA
reviews and approves/disapproves  the standards
based  on  whether  the  standards  meet   the
requirements   of the  CWA  and  the  Water
Quality   Standards   Regulation.     States   are
encouraged to provide early drafts to the EPA
Regional  Office so that  issues can be resolved
during  the  water   quality  standards  review
process,  prior  to  formal  State  proposal  or
adoption of revised or new standards.

When reviewing  State water quality standards,
EPA  ensures  that  the  standards  meet   the
minimum requirements   of the  Act  and Water
Quality   Standards  Regulation.   Pursuant  to
section  510  of the Act,  State  water quality
standards may be more  stringent than EPA's
minimum requirements.

The  general  elements   of an  EPA review
include,  but are not limited to, the  following:

•  EPA   determines    whether  "fishable/
   swimmable"   designated  uses   have  been
   assigned  to  all  State  waters  or  a  use
   attainability analysis  (UAA) is available to
   support  the  designation   of  other  uses.
   Other  uses may satisfy the  CWA section
   101(a)(2)  goal if properly  supported  by a
   UAA.   EPA  reviews the  adequacy  of the
   analyses.

•  EPA determines  whether the  State's  water
   quality criteria are sufficient  to protect  the
   designated  uses by ensuring that all numeric
   criteria  are based on CWA Section  304(a)
   guidance,   304(a)  guidance   modified   to
   reflect   site-specific  conditions,  or  other
   scientifically  defensible  methods.  EPA's
   decision  to accept criteria based on site-
   specific calculations  or alternative  scientific
   procedures  is based  on a determination  of
   the validity and adequacy of the supporting
   scientific procedures  and  assumptions  and
   not on whether  the  resulting criterion  is
   more   or  less  stringent   than  the  EPA
   guideline.

•  EPA ensures  that uses  and/or criteria  are
   consistent  throughout the  water  body  and
   that downstream  standards are protected.  A
   review  to   determine   compliance   with
   downstream   standards  is  most   likely to
   involve bodies  of water  on,  or crossing,
   interstate  and international  boundaries.

•  Where the analyses  supporting any changes
   in  the  standards  are  inadequate,   EPA
   identifies   how  the  analyses  need   to  be
   improved    and   suggests   the   type   of
   information or analyses needed.

•  For  waters  where  uses   have  not  been
   designated   in  support  of  the   fishable/
   swimmable  goal  of  the   CWA,  EPA
   determines  whether the alternative uses are
   based on an acceptable  UAA and whether
   such UAAs have  been  reviewed every 3
   years as required by 40 CFR 131.20(a).

•  EPA   ensures   that   general   "free  from"
   narrative  criteria are included that protect
   all waters  at all flows from substances  that
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                                     Chapter 6 - Procedures for Review and Revision of Water Quality Standards
                          State Submits Draft
                          WQS to Region for
                           Informal Review
                                T
                         Region Reviews Draft
                               WQS
                    HQ Reviews Draft WQS
                         Comments Given to
                                State
                                I
                           State Adopts or
                            Revises WQS
             State Submits Revisions, Methods, Justifications
              and Attorney General Certification to Regional
                       Administrator for Review
                                 or
                        or
                     (60 days)
            (90 days)
         Regional Administrator
            Approves WQS
Regional Administrator
  Disapproves WQS
                                                   (90 days)
                             Yes
       State
      Adopts
      Required
      Changes
                                            EPA Begins
                                           Promulgation
                              Concurrent HQ Review
Regional Administrator
Conditionally Approves
WQS
1
r
If Conditions Not Met
   by State, WQS
    Considered
    Disapproved
  Figure 6-2. Overview of EPA Water Quality Standards Review Process
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Water Quality Standards Handbook - Second Edition
   settle to form  objectionable  deposits;  float
   as  debris,  scum,  oil,  or   other  matter;
   produce  objectionable color, odor, taste, or
   turbidity;  are  acutely  toxic;  or produce
   undesirable or nuisance  aquatic  life.

•  EPA  determines   whether  the  State  has
   included  criteria  for  CWA  section  307(a)
   "priority" pollutants sufficient to satisfy the
   requirements of CWA section 303(c)(2)(B).

•  For toxic pollutants  where  EPA  has not
   issued guidance  or it is not  known  which
   toxicant   or  toxicants   are  causing  the
   problem,  EPA   ensures   that   the   State
   standards include or reference a method  for
   implementing   the  narrative  toxics  "free
   from" criterion.

•  EPA  ensures that the State's antidegradation
   policy meets  the  requirements   of  section
   131.12  of  the  Water  Quality  Standards
   Regulation.

•  EPA  reviews whether  the State has provided
   or referenced  a procedure  for implementing
   the antidegradation  policy.

•  Where   (optional)   general   policies  are
   included in the State water quality standards
   (e.g., mixing  zone  provisions,  variance
   policies, low-flow exemption  policies), EPA
   reviews  whether  the policies are consistent
   with  the latest EPA guidance.

•  EPA  reviews comments and  suggestions on
   previous  State water quality  standards   to
   ensure  that any  areas for improvement  or
   conditions  attached  to  previous approvals
   have  been acted  upon satisfactorily.

•  EPA   reviews  whether  the policies  are
   consistent with the latest EPA guidance and
   regulatory requirements.

•  EPA  ensures  that  the  State has  met  the
   minimum   requirements   for  a  standards
   submission  as  outlined  in  section  131.6 of
   the Water  Quality  Standards  Regulation.

•  EPA   reviews   whether   the   State  has
   complied  with the  procedural  requirements
   (e.g., public participation)   for conducting
   water quality  standards  reviews.

Since  1972,   EPA   review  and  approval/
disapproval  includes concurrent  reviews by the
Regions and Headquarters.   However, because
the  EPA   regional   Administrator    has  the
responsibility for approving/disapproving water
quality   standards    and    because    of  the
decentralized  structure  of EPA,  the  regional
offices are the primary point of contact with the
States.   The EPA regional  offices,  not the
States, are responsible for providing copies  of
State  water  quality   standards   to  EPA
Headquarters   for review  and  for acting  as
liaison between States and EPA Headquarters
on  most  matters   affecting the water quality
standards  program.   The  basic internal  EPA
review  procedures  have  been  described  in
various guidance  documents over the years; the
most was a  memorandum  dated December 17,
1984. This memorandum  also  made  one minor
change to  the  process.    It  required  that
Headquarters   be  consulted  immediately  for
possible   advice    and  assistance   when   the
Regional Office learns that a  State:

•  is proposing to lower designated  water uses
   below the section 101(a)(2) goals of the Act;

•  is not raising water uses to meet  the section
   101(a)(2) goals of the Act; or

•  is  considering  adopting   a  water quality
   criterion   less   stringent   than    currently
   included in a State's standard.

To  expedite  Headquarters  review, copies  of
State  water  quality standards  revisions  (draft
and  final)  must  be provided  to the  Director,
Standards and Applied Science Division, at the
time they  are received  by the Region.   The
Standards  and  Applied  Science  Division will
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                                    Chapter 6 - Procedures for Review and Revision of Water Quality Standards
involve  other  EPA  offices  in the  review as
appropriate,    and   provide    comments   and
suggestions,  if  any, to  regional   offices for
consideration   in State-EPA   negotiations  and
final  standards decisions.  Their  review will be
expeditiously  accomplished  so as  not to slow
regional  approval/disapproval.    Neither  the
regional  nor  Headquarters   review  need  be
limited only to revisions to existing standards or
to new standards.

In general, three  outcomes are possible:

•   EPA approval, in whole  or in  part, of the
    submitted  State water quality standards;

•   EPA disapproval, in whole or in part, of the
    submitted  State water quality standards;  and

•   EPA conditional  approval, in whole or in
    part, of the  submitted  State  water  quality
    standards.

Unconditional   approval   or  disapproval  of
State-adopted  water quality standards within the
statutory time  limits  is the preferred  approach.
Conditional approvals should  be  used only as a
limited  exception to this general  policy for
correcting minor deficiencies  in State standards
and only if a  State  provides  assurance  that  it
will submit  corrections  on a  specified,  written
schedule.  Failure of a State  to respond in a
timely manner to the  conditions  expressed in
the   letter  means   that  the  standards   are
disapproved  and the  Region must  promptly
request Headquarters to initiate a promulgation
action.   Where this  occurs, the Region  should
formally notify the  State  in  writing that  their
failure   to  meet  the  conditions   previously
specified  results   in  the  standards   now being
disapproved  as  of  the  original  date  of the
conditional approval  letter.

6.2.1  Policies   and  Procedures  Related  to
       Approvals

Authority to approve or disapprove  State water
quality   standards   is   delegated    by   the
Administrator  to each Regional Administrator.
The  Administrator  retains  the  authority  to
promulgate standards.  Revisions to State water
quality standards that meet the requirements of
the  Act  and  the  Water  Quality  Standards
Regulation  are  approved  by  the  appropriate
EPA Regional  Administrator.    The Regional
Administrator  must, within 60 days, notify the
Governor  or  his  designee  by  letter   of the
approval and forward a copy of the letter to the
appropriate  State  agency.   The letter  should
contain any information  that might be helpful in
understanding  the  scope of the approval  action.
If particular events (e.g., State implementation
decisions, pending Federal legislation pertaining
to water quality standards  requirements)  could
result  in a failure of the approved standards to
continue to meet  the requirements  of the Act,
these   events  should   be  identified  in  the
approval   letter.     Such  events  should  be
identified for the record to guide future  review
and  revision activities.

When  only a portion of the revisions  submitted
meet  the  requirements  of  the  Act  and the
Water  Quality   Standards   Regulation,   the
Regional  Administrator  may approve only that
portion. If only a partial approval is made, the
Region  must,  in  notifying  the  State,  be  as
specific  as  possible in  identifying  what is
disapproved    and   why.      The   Regional
Administrator  must  also clearly  indicate  what
action   the State  could  take  to  make  the
disapproved item  acceptable.

6.2.2  Policies  and  Procedures  Related  to
       Disapprovals

If the  Regional Administrator  determines that
the revisions submitted  are not consistent with
or do not meet the requirements  of the  Act or
the Water Quality  Standards  Regulation,  the
Regional  Administrator must disapprove  such
standards   within  90 days.   Such  disapproval
must be via written notification  to the Governor
of the  State or his designee.   The letter  must
state why the  revisions are not consistent  with
the  Act  or  the  Water  Quality  Standards
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Water Quality Standards Handbook - Second Edition
Regulation  and specify the revisions  that must
be adopted  to obtain full approval.  The letter
must   also   notify  the  Governor   that   the
Administrator    will   initiate    promulgation
proceedings  if the  State fails  to adopt  and
submit  the  necessary  revisions within 90 days
after notification.

A State  water  quality  standard  remains   in
effect,  even though  disapproved   by EPA, until
the State  revises it or EPA promulgates  a rule
that   supersedes   the    State  water  quality
standard.     This  is  because   water  quality
standards  are State  laws, not  Federal  laws, and
once  the  law is  amended  by the  State,  the
previously   adopted    and   EPA-approved
standards  no longer legally exist.

6.2.3  Policies  and  Procedures Related   to
       Conditional  Approvals

Conditional    approvals   are   EPA   approvals
contingent  on  the  performance   of specified
actions  on  the part  of a State  in a  timely
manner.    There  is  an  implicit  or  explicit
statement  in the letter to the State that failure
to satisfy  the identified   conditions will nullify
the conditional  approval and lead to Federal
promulgation  action. Problems have arisen with
inconsistent  use of conditional approvals among
the regions and with followup actions  to ensure
that a State  is responding to the conditions in a
timely  manner.
Because promulgation  of Federal  standards  is
inherently   a  lengthy  process,   the  use  of
conditional  approvals  evolved over the  years as
another   mechanism    to    maintain   the
State-Federal    relationship   in   establishing
standards.   When used properly, conditional
approvals can result in standards that  fully meet
the  requirements   of the  Act without undue
Federal  intervention   and  promote  smooth
operation of the national  program.

If used improperly, conditional approvals can be
an unacceptable  delaying tactic to establishing
standards and can be  construed  as EPA failing
to properly  exercise  its  duty to  review  and
either   approve  or disapprove  and  promptly
initiate  promulgation  action  after  the  allotted
90-day  period for State  action.  This improper
use of conditional  approvals  must be avoided.

It is incumbent  on  a  Region   that  uses  a
conditional  approval to ensure that State action
is timely.   When a  State fails  to  meet  the
agreed-upon  schedule,   EPA  should  initiate
promulgation  action. Conditional  approvals are
to be used  only to correct minor deficiencies
and  should  be the  exception, not  the  rule,
governing regional responses to State  standards.
Note that requests for clarification  or additional
information  are not  approval actions  of any
type.

This policy is modeled  after  that applied to
EPA approval  of State  implementation  plans
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                                   Chapter 6 - Procedures for Review and Revision of Water Quality Standards
 (SIPs) in the air program.  (See 44 F.R. 38583,
 July 2, 1979.  See also Mississippi Commission
 on Natural Resources v. Costle, 625 F. 2d  1269
 (5th Cir.) 1980.)

    Necessary   Elements   of   Conditional
    Approvals

 First, conditional approvals are appropriate  only
 for "minor deficiencies."  Blatant  disregard  of
 Federal  statutory  or regulatory  requirements  or
 changes  that  will affect major  permit  issuance
 or reissuance  are not minor deficiencies.   In
 addition, the  State's  standards  submission  as a
 whole must be in substantial  compliance  with
 EPA's regulation.  Major deficiencies  must  be
 disapproved   to   allow   prompt   Federal
 promulgation  action.

 Second,  the State must commit, in writing, to a
 mutually satisfactory,  negotiated  schedule  to
 correct the identified  regulatory deficiencies  in
 as short a  time period  as  possible.  The time
 allowed  should bear a reasonable  relationship
 to  the   required   action.     However,   in
 consideration  of the first element  above,  it is
 expected that  the  time period  for compliance
 will be limited to  a few months. It is definitely
 not  expected  that  a  year or more  will  be
 required. If that is the case, disapproval  would
 be  more   appropriate.      Headquarters
 concurrence in the schedule  is required  if it
 extends  for more  than  3 months.
       EPA Promulgation
As a matter  of policy, EPA prefers that  States
adopt  their  own  standards.  However,  under
section   303(c)(4)   of  the  Act,  EPA  may
promulgate  Federal standards:

•   if a  revised or new water quality standard
    submitted  by a State  is determined  by the
    Administrator  not to be consistent with the
    requirements  of the Clean Water Act, or
 •  in   any  case  where  the  Administrator
    determines that a new or revised standard is
    necessary  to  meet the requirements  of the
    Act.

 Under  the latter provision of the  statute, EPA
 would  be  able  to  promulgate  standards  for a
 State,   or  States,  that  failed  to  conduct a
 triennial  review and  submit new  or revised
 standards  to  EPA for  review so  long  as  the
 Administrator  determined  new standards were
 necessary.   Where one  of these  conditions is
 met,  the Administrator  has  the  authority  to
 publish  proposed  revisions  to   the  State(s)
 standards in the Federal Register. Generally, a
 public  hearing  will be  held on  the proposed
 standards.  Final standards  are   promulgated
 after   giving  due   consideration   to  written
 comments  received and  statements made at  any
 public hearings  on the proposed revisions.

 Although   only  the   Administrator   may
 promulgate State standards, the Regional  Office
 has a major  role in the  promulgation  process.
 The Regional  Office  provides  the  necessary
 background   information  and  conducts   the
 public hearings.  The Regional Office prepares
 drafts of the  rationale supporting  EPA's action
 included in the proposed  and final  rulemakings.
 The rationale  should clearly state the reason  for
 the disapproval  of  the State standard.

 If conditions  warrant  (e.g., a State  remedies  the
 deficiencies in its water quality standards  prior
 to  promulgation),    the  Administrator   may
 terminate  the rulemaking  proceeding  at any
 time.  However,  if a proposed rulemaking  has
 been published in the Federal Register, then  the
 Regional Administrator   must not  approve  the
 State's  changes  without  obtaining  concurrence
 from Headquarters.

Whenever   promulgation   proceedings   are
terminated,  a notice  of  withdrawal of the
proposed  nilemaking  will be published  in the
Federal Register.  The  Regional  Offices are
responsible  for  initiating   such  action  and
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Water Quality Standards Handbook - Second Edition
furnishing  a rationale for use in preparing  the
notice for  the Administrator's signature.

An   EPA-promulgated    standard    will   be
withdrawn  when revisions to State water quality
standards are made  that meet the requirements
of the Act.  In such a situation, the Regional
Office should initiate the withdrawal action by
notifying the Standards  and Applied  Science
Division (WH-585)  that  it  is  requesting  the
withdrawal,  specifying  the  rationale   for  the
withdrawal,   and    obtaining    Headquarters
concurrence  on the acceptability of the State's
water  quality   standards.    EPA's action  to
withdraw  a federally promulgated   standard
requires  both a proposed  and final rulemaking
if the State-adopted  standards are less stringent
than federally promulgated standards but, in the
Agency's judgment, fully meet the requirements
of the Act.  EPA will withdraw the Federal rule
without a notice and comment rulemaking when
the State standards  are  no  less stringent than
the Federal rule (i.e.,standards  that provide, at
least,  equivalent  environmental  and  human
health protection).

Withdrawal of a Federal  promulgation  is based
on  a determination   that  State-adopted  water
quality standards meet the requirements of the
Clean   Water  Act.     Such    State-adopted
standards may be the same  as,  more  stringent
than, or less stringent than the Federal rule.
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                                 Chapter 7 - The Water Quality-Based Approach to Pollution Control
                                CHAPTER?

                     THE WATER QUALITY-BASED
                              APPROACH TO
                         POLLUTION CONTROL
                             Table of Contents


7.1  Determine Protection Level	7-2

7.2  Conduct Water Quality Assessment	7-3
    7.2.1    Monitor Water Quality  	7-3
    7.2.2    Identify Impaired (Water Quality-Limited) Waters	7-3

7.3  Establish Priorities  	7-5

7.4  Evaluate Water Quality Standards for Targeted Waters	7-6

7.5  Define and Allocate Control Responsibilities  	7-7

7.6  Establish Source Controls	7-8
    7.6.1    Point Source Control - the NPDES Process	7-9
    7.6.2    Nonpoint Source Controls  	7-9
    7.6.3    CWA Section 401 Certification	7-10

7.7  Monitor and Enforce Compliance	7-12

7.8  Measure Progress	7-13

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                                         Chapter 7 - The Water Quality-Based Approach to Pollution Control
                                        CHAPTER 7
                     THE WATER QUALITY-BASED APPROACH
                              TO POLLUTION CONTROL
This chapter briefly describes the overall water
quality-based  approach  and its relationship to
the water quality standards program.  The water
quality-based  approach emphasizes  the overall
quality  of  water  within  a  water  body  and
provides  a  mechanism   through  which  the
amount of pollution entering  a water body  is
controlled  based on the intrinsic conditions of
that body of water and the standards  set to
protect  it.

As shown in Figure  7.1, the water quality-based
approach  contains  eight  stages.   These  stages
each  represent   a  major  Clean  Water  Act
program with specific regulatory  requirements
and guidance. The presentations  in this chapter
summarize how the different programs  fit  into
the overall  water quality  control scheme  and
are not intended as implementation  guidance.
Implementation   of these  programs  should be
consistent   with  the   specific  programmatic
regulations  and guidance  documents  provided
by the  appropriate  program  office, many of
which are cited  herein.

The first stage, "Determining Protection  Level,"
involves State development  of water  quality
standards, the subject of the preceding chapters
of this Handbook.

In the second stage, "Monitoring and Assessing
Water Quality,"States  identify impaired  waters,
determine if water quality standards  are being
met, and  detect pollution  trends.  Sections of
the Clean Water Act require States  to compile
data,  assess,  and report on the status  of their
water bodies.   States  generally use  existing
information   and   new  data  collected  from
ongoing  monitoring programs to assess their
waters.  This  stage  is  discussed in section  7.2.
of this Handbook.
In  the  third  stage,   "Establishing  Priorities,"
States  rank  water  bodies  according  to  the
severity of the pollution, the uses to be made of
the   waters,   and   other    social-economic
considerations,   and  determine  how  best  to
utilize available  resources  to solve  problems.
Section 7.3  of this  Handbook  discusses  the
ranking and  targeting  of water bodies.

In  the  fourth  stage,  "Evaluating  WQS  for
Targeted  Waters," the appropriateness  of the
water quality standards for  specific  waters  is
evaluated.  States may revise or reaffirm their
water quality standards.  A State may choose,
for example,  to develop site-specific criteria for
a particular stream because a particular  species
needs to be protected.  This  stage is discussed
in section 7.4 of this Handbook.

In  the  fifth stage  "Defining and  Allocating
Control Responsibilities,"  the level  of  control
needed  to  meet  water  quality  standards   is
established,  and  control  responsibilities   are
defined and allocated.  States  use mathematical
models  and/or   monitoring to determine total
maximum  daily  loads  (TMDLs)  for water
bodies;   the  TMDLs  include  waste  load
allocations  (WLAs)  for  point  sources,  load
allocations (LAs)  for  nonpoint  sources, and  a
margin of safety.  The TMDL is the amount of
a pollutant that may be discharged  into a water
body and  still maintain  water  quality  standards.
Pollutant  loadings above this  amount  generally
will result in waters  exceeding the  standards.
Allocations  for pollution  limits for point and
nonpoint  sources are calculated to ensure that
water  quality  standards  are  not  exceeded.
Section  7.5  discusses  the TMDL  process  in
greater detail.
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Water Quality Standards Handbook - Second Edition
                                              1
                                  Determine Protection Level
                                  Review/Revise State WOS
                       8
                Measure Progress
              Modify TMDL if needed
         Monitor and Enforce
             Compliance
            Self-Monitoring
          Agency Monitoring
             Enforcement
         Conduct WQ Assessment
          (a) Monitor Water Quality
          (b) Identify Impaired Waters
                       \
                 Establish Priorities
               Rank/ Target Waterbodies
                  \
         Establish Source Controls
            Point Source Permits
              NPS Programs
             §401 Certification
               Evaluate WQS for
               Targeted Waters
             Reaffirm / Revise WQS
                           Define and Allocate Control Responsibilities
                                       TMDL/WLA/LA
    Figure 7-1.  Water Quality-Based Approach to Pollution Control
In the sixth stage, "Establishing Source Control,"
States   and  EPA   implement   point  source
controls  through NPDES permits,  State  and
local governments implement  nonpoint  source
management  programs through State laws and
local ordinances, and  States  assure attainment
of water quality standards  through  the  CWA
section   401   certification process.    Control
actions  are discussed in Section 7.6.

In the seventh stage, "Monitoring and Enforcing
Compliance," States  (or EPA)  evaluate   self-
monitoring data reported by dischargers to see
that  the conditions  of the NPDES permit are
being   met  and  take  actions   against   any
violators.    Dischargers  are  monitored  to
determine  whether  or  not  they  meet  permit
conditions  and  to ensure that  expected  water
quality   improvements   are  achieved.    State
nonpoint  source  programs  are  monitored  and
enforced  under  State  law and  to the  extent
provided by State law.

In the  final  stage,  "Measuring  Progress," the
States (and EPA) assess the effectiveness of the
controls  and  determine  whether  water quality
standards have  been  attained,  water  quality
standards need to be revised, or more stringent
controls  should be applied.
          Determine Protection Level
The water quality-based approach to pollution
control   begins  with   the   identification   of
problem  water bodies.   State   water  quality
standards  form the  basis  and   "yardstick"  by
which States can assess the water body status
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                                         Chapter 7 - The Water Quality-Based Approach to Pollution Control
and implement  needed  pollution controls.   A
water quality standard defines the water quality
goals of a water  body,  or portion  thereof,  by
designating  the  use or uses to be made of the
water, by setting  criteria  necessary  to protect
the  uses, and  by preventing  degradation  of
water   quality   through  antidegradation
provisions. States adopt  water quality standards
to protect public health or welfare, enhance the
quality of water, and serve the purposes of the
Clean  Water  Act.  "Serve the purposes of the
Act" (as defined in sections 101(a), 101(a)(2),
and 303(d) of the Act) means that water quality
standards  should  (1)  include  provisions for
restoring  and maintaining  chemical, physical,
and biological  integrity  of State   waters; (2)
provide,  wherever  attainable, water  quality for
the protection and propagation  of fish, shellfish,
and wildlife, and recreation in and on the water
("fishable/swimmable");  and (3)  consider the
use  and  value of State waters for public water
supplies,  propagation   of fish  and  wildlife,
recreation, agricultural and industrial purposes,
and navigation.  The preceding chapters of this
Handbook   provide  EPA's guidance  on the
water quality  standards program.
          Conduct Water Quality Assessment
Once  State  water  quality   standards   have
determined  the appropriate  levels of protection
to be  afforded  to State  water  bodies, States
conduct  water quality monitoring  and identify
those waters that are "waterquality limited,"or
not meeting  the standards.

7.2.1    Monitor Water Quality

Monitoring  is an important element  throughout
the  water   quality-based   decision   making
process.  In this step, monitoring provides  data
for identifying impaired  waters.   The Clean
Water  Act specifies that  States  and Interstate
Agencies, in cooperation  with  EPA,  establish
water quality monitoring  systems necessary to
review and revise water quality standards, assess
designated  use attainment,  calculate  TMDLs,
 assess compliance  with permits, and report on
 conditions and trends in ambient  waters.  EPA
 issued  guidance   in 1985  for  State  Water
 Monitoring and Waste load Allocation (USEPA,
 1985d).  Guidance  for preparing  CWA section
 305 (b) reports  is contained  in the  Guidelines for
 the Preparation of the 1994 State  Water Quality
 Assessments  (305 (b) Reports) (USEPA,  1993a).
 Both of these documents  discuss monitoring as
 an  information   collection   tool  for  many
 program  needs.  The Intergovernmental  Task
 Force on Monitoring Water  Quality report
 (ITFM,  1992)  proposes   actions  to  improve
 ambient  water quality monitoring  in the United
 States to  allow  better management  of water
 resources.

 Sections 208(b)(2)(F)  through (K) of the CWA
 require the development  of a State process to
 identify, if appropriate, agricultural, silvicultural,
 and other  nonpoint  sources of pollution.  NFS
 monitoring concerns  are  discussed  in several
 NPS guidance documents  along with methods to
 monitor    and   evaluate   nonpoint    sources
 (Watershed    Monitoring   and   Reporting
 Requirements  for    Section   319   National
 Monitoring Program  Projects (USEPA,  1991g)
 and Guidance Specifying Management Measures
for Sources  of Nonpoint  Pollution  in  Coastal
       (USEPA,  1993b).
Identify  Impaired  (Water  Quality-
Limited) Waters
7.2.2
EPA's   Water   Quality   Planning   and
Management  Regulation  (40 CFR  Part  130)
establishes  the process  for  identifying  water
quality-limited   water   still   requiring   total
maximum   daily  loads  (TMDLs).    Waters
require TMDLs when certain pollution control
requirements (see Exhibit 7. 1) are not stringent
enough to maintain  water quality standards for
such waters.

The  most  widely  applied   water  pollution
controls   are   the   technology-based   effluent
limitations required  by sections 301(b)  and 306
of the  Clean Water Act. In some cases, a State
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   (b)(l) Each State shall identify those water quality
   segments still requiring WLAs/LAs and TMDLs
   within its boundaries for which:

       (i) Technology-based effluent limitations
       required by sections 301 (b), 306, 307, or
       other section of the Act;

       (ii) More stringent effluent limitations
       (including prohibitions) required by either
       State or local authority preserved by section
       510 of the Act, of Federal authority (e.g.,
       law,  regulation, or treaty); and

       (iii) Other pollution control requirements
       (e.g., best management practices) required by
       local, State, or Federal authority

   are not stringent enough to implement any water
   quality standard applicable to such waters.
Exhibit 7-1. Identifying Waters Still Requiring
             TMDLs: 40 CFR 130.7(b)
or  local  authority  may establish  enforceable
requirements beyond technology-based controls.
Examples  of such requirements  may be  those
that (1) provide more  stringent  NPDES permit
limitations to protect a valuable  water resource,
or (2) provide for the management  of certain
types of nonpoint source pollution.

Identification of  good quality waters  that  are
threatened   is  an  important   part  of  this
approach.  Adequate control of new discharges
from either point  or nonpoint  sources should be
a  high  priority   for  States  to  maintain  the
existing  use or uses of these water bodies.  In
the  identification  of threatened  waters,  it is
important  that the 303(d)  process consider all
parts  of the  State   water  quality standards
program    to    ensure   that    a   State's
antidegradation  policy and narrative  provisions,
as  well  as parameter-specific   criteria,   are
maintained.
Section 303(d) requires States to identify those
water  quality-limited waters  needing  TMDLs.
States  must regularly update their lists of waters
as assessments are  made  and report these lists
to EPA once every 2 years.  In their biennial
submission,  States   should  identify  the  water
quality-limited   waters   targeted  for  TMDL
development  in the  next 2 years,  and  the
pollutants  or stressors  for which the  water  is
water  quality-limited.

Each  State  may have different  methods  for
identifying  and  compiling information on the
status  of its water bodies,  depending  on  its
specific  programmatic  or cross-programmatic
needs    and   organizational    arrangements.
Typically,   States   utilize   both   existing
information   and   new  data  collected  from
ongoing monitoring programs to  assess whether
water  quality standards are being met, and to
detect  trends.

States   assess  their waters  for a  variety  of
purposes, including targeting cleanup  activities,
assessing  the   extent  of contamination   at
potential Superfund  sites, and meeting  federally
mandated  reporting requirements.   While the
identification  of water  quality-limited  waters
may appear to be a major task for the States, a
significant  amount   of  this work has  already
begun  or has been  completed   under sections
305(b), 304(1), 314(a), and 319(a)  of the Clean
Water  Act as amended  in 1987.

Section  305 (b)   requires  States   to  prepare  a
water   quality   inventory  every  2  years  to
document the status of water bodies  that have
been assessed.   Under  section   304(1), States
identified all surface waters adversely affected
by   toxic   (65    classes   of    compounds),
conventional  (such  as  BOD,  total  suspended
solids, fecal  coliform, and oil and grease), and
nonconventional   (such as ammonia,   chlorine,
and  iron)  pollutants   from  both point  and
nonpoint sources.  Under  section 314(a), States
identify publicly  owned lakes for which uses are
known to be impaired  by point  and nonpoint
sources, and report  those  identified  in their
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                                          Chapter 7 - The Water Quality-Based Approach to Pollution Control
 305(b)  reports.    Section   319 of  the  CWA
 requires  each   State   to   develop  an   NFS
 assessment  report. Guidance on the  submission
 and approval process for Section 319 reports is
 contained    in   Nonpoint   Source   Guidance
 (USEPA, 1987c).

 Lists prepared  to satisfy requirements   under
 section 305(b), 304(1), 314(a) and 319 should be
 very useful  in preparing 303(d) lists.  Appsndix
 B   of   Guidance  for  Water  Quality-based
 Decisions: The TMDL Process (USEPA,  1991c)
 provides a  summary of these supporting
 programs.
          Establish Priorities
l
Once waters  needing additional  controls
been identified,  a  State  prioritizes  its
waters using established ranking processe
should  consider  all  water  pollution  control
activities  within the State.  Priority rankin
traditionally been a process defined by the
and may vary in  complexity and design
priority  ranking   should enable  the Sta
make efficient use of its available  resource
meet the  objectives of the  Clean  Water Act
have
st  of
 that
 I has
 State
    A
    to
  and
The Clean  Water  Act states  that  the  priority
ranking for such waters must take into account
the severity of the pollution and the uses "o be
made  of  such  waters.    Several  documents
(USEPA, 1987e, 1988c,d, 1989d, 1990c, 1993c)
are  available  from  EPA  to assist  States  in
priority setting.

According to EPA's State Clean Water Strategy
document:  "Where all water  quality  problems
cannot be addressed immediately, EPA and the
States  will, using  multi-year  approaches,  set
priorities  and  direct efforts  and resources to
maximize environmental   benefits  by  dealing
with the most  serious water quality  problems
and the most valuable and threatened  resources
first."
Targeting   high-priority   waters   for  TMDL
development should reflect an evaluation of the
relative  value  and  benefit  of  water bodies
within the State and take into consideration the
following:

•    risk to human  health,  aquatic  life, and
     wildlife;

•    degree of public interest  and support;

•    recreational,   economic,  and   aesthetic
     importance  of a particular water body;

•    vulnerability  or fragility of a  particular
     water body as an aquatic habitat;

•    immediate  programmatic  needs  such  as
     waste load allocations needed for permits
     that are coming up for revisions  or for new
     or   expanding    discharges,   or   load
     allocations  for needed BMPs;

•    waters  and pollution problems  identified
     during  the development  of the  section
     304(1)  "long list";

•    court   orders  and  decisions relating   to
     water quality; and

•    national  policies  and  priorities  such  as
     those    identified    in   EPA's   Annual
     Operating  Guidance.

States  are  required  to  submit   their priority
rankings to  EPA  for review.  EPA expects all
waters  needing   TMDLs  to  be  ranked,  with
"high" priority waters — targeted  for initiation
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of TMDL development within 2 years following
the listing process — identified.   (See US EPA
(1991c)  for  further details  on  submission of
priorities to EPA.)

To effectively develop and implement TMDLs
for all waters identified,  States should establish
multi-year    schedules   that    take    into
consideration    the   immediate   TMDL
development  for targeted  water bodies and the
long-range planning  for addressing  all water
quality-limited  waters  still requiring  TMDLs.

While the  CWA  section  319 NPS assessment
report identifies  the overall dimensions  of the
State's NPS water quality  problems  and States
are to develop  statewide  program  approaches
for specific  categories of  pollution  to address
NPS problems,  States are also encouraged to
target  subsets of waters for concerted  action on
a  watershed-by-watershed   basis.   EPA  has
issued guidance  on  NPS targeting  (USEPA,
1987e).
          Evaluate Water Quality Standards
          for Targeted Waters
At this point in the water quality management
process,  States  have  identified  and targeted
priority water quality-limited water bodies.  It is
often   appropriate,   to   re-evaluate   the
appropriateness  of the water quality standards
for the  targeted  waters  for  several  reasons
including, but not limited to, the  following.

First, many States have not conducted in-depth
analyses of appropriate uses and criteria for all
water  bodies  but  have  designated  general
fishable/swimmable    use   classifications   and
statewide  criteria   on  a   "best  professional
judgment"  basis to many waters.  In addition,
many States make general  assumptions  about
the antidegradation  status of State waters  (e.g.,
all  waters  not  specifically  assigned  to  an
antidegradation  category will be considered tier
2 or  high-quality  waters).   It  is possible  that
these  generally  applied   standards,  although
meeting  the  minimum  requirements   of the
CWA   and   WQS   regulation,   may   be
inappropriate  (either over- or under-protective)
for a specific water body that has not had an in-
depth  standards  analysis.  For example,  if a
water body was classified as a coldwater fishery
based solely on its proximity to other coldwater
fisheries,  a water  body-specific  analysis  may
show  that  only  a  warmwater  fishery use  is
existing or attainable.  If the  listing of the water
body was based on exceedences of criteria  that
are more stringent for coldwater fish  (such as
ammonia  or  dissolved  oxygen),  changing the
designated  use  through  a  use  attainability
analysis and applying appropriate  criteria  may
allow standards to be met without further water
quality controls.

Second, even if an  in-depth analysis has been
done  in the past, changes  in the uses of the
water  body  since that  time may have made
different   standards   more  appropriate   or
generated  an  additional "existing use" which
must be protected.   For example, a water body
designated for fish, aquatic  life, and  recreation
in the past may now be used as a public water
supply, without that use and protective  criteria
ever being formally adopted  in the  standards.
Another   example  might   be   a  designated
warmwater  fishery that, due to the removal of
a thermal discharge,  now supports a coldwater
fishery as the existing use.

Third, monitoring  data  used  to  identify the
water body  as impaired  may be historical, and
subsequent  water quality improvements  have
allowed standards to be met. And fourth,  site-
specific criteria may be appropriate  because of
specific local environmental  conditions.   For
example, the species capable of living at the site
are more or less sensitive than those included
in the national  criteria  data  set, or physical
and/or chemical  characteristics  of the site alter
the biological availability and/or toxicity of the
chemical.
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                                         Chapter 7 - The Water Quality-Based Approach to Pollution Control
          Define   and   Allocate
          Responsibilities
Control
For a  water  quality-limited  water  that  still
requires a  TMDL,  a  State  must  establish  a
TMDL that quantifies  pollutant  sources, and  a
margin of safety, and allocates  allowable  loads
to the contributing  point  and nonpoint source
discharges so that  the  water quality  standards
are  attained.    The development  of TMDLs
should  be accomplished  by setting  priorities,
considering  the geographic area impacted by
the pollution problem,  and in some cases where
there are uncertainties   from lack of adequate
data, using  a phased approach  to establishing
control measures based on the TMDL.

Many  water pollution  concerns  are  areawide
phenomena   caused  by  multiple dischargers,
multiple pollutants  (with potential  synergistic
and additive  effects),  or  nonpoint  sources.
Atmospheric  deposition   and   ground  water
discharge may also  result in significant pollutant
loadings to  surface waters.  As a result, EPA
recommends that  States develop TMDLs on  a
watershed  basis to  efficiently  and  effectively
manage  the quality of  surface waters.

The TMDL process is a rational method  for
weighing the competing pollution concerns and
developing  an  integrated   pollution   reduction
strategy  for  point  and nonpoint sources.  The
TMDL process  allows  States to take  a holistic
view of their water quality problems  from  the
perspective  of instream  conditions.  Although
States  may define a water body to correspond
with their current programs, it is expected  that
States  will  consider  the  extent  of pollution
problems   and   sources  when  defining  the
geographic  area  for developing TMDLs.   In
general, the geographical approach for TMDL
development   supports  sound   environmental
management  and efficient use of limited water
quality  program  resources.    In  cases  where
TMDLs  are developed   on watershed  levels,
States  should  consider  organizing permitting
cycles  so that all permits in a given watershed
expire  at the same  time.

For traditional  water pollution  problems, such
as dissolved  oxygen  depletion  and  nutrient
enrichment,   there  are  well-validated   models
that  can predict  effects with known levels of
uncertainty.     This   is  not  true  for  such
nontraditional  pollution  problems  as  urban
stormwater  runoff  and pollutants  that  involve
sediment   and   bioaccumulative    pathways.
Predictive   modeling    for   these  problems
therefore uses conservative  assumptions, but in
many cases the degree of uncertainty cannot be
well  quantified   until  more   data   become
available  to  develop  sensitivity analyses  and
model  comparisons.   For  TMDLs involving
these  nontraditional problems,  the margins of
safety   may   be   increased   and   additional
monitoring  required   to  verify  attainment  of
water  quality  standards  and  provide  data
needed  to recalculate  the TMDL,  if necessary
(the phased  approach).

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EPA  regulations  provide that  load  allocations
for nonpoint  sources and natural  background
"are best  estimates  of  the  loading  which may
range  from reasonably  accurate  estimates  to
gross allotments  .  . ."(40  CFR 130.2(g)).  A
phased approach  to developing TMDLs may be
appropriate    where  nonpoint  sources   are
involved and  where estimates are  based on
limited   information.     Under  the  phased
approach,   TMDL   includes   monitoring
requirements  and  a schedule  for  reassessing
TMDL  allocations  to  ensure  attainment  of
water  quality standards.    Uncertainties  that
cannot be quantified may also exist for certain
pollutants discharged primarily by point sources.
In such situations  a large margin of safety and
followup monitoring are appropriate.

By pursuing  the   phased   approach   where
applicable,   a  State  can  move   forward  to
implement water quality-based control measures
and   adopt   an   explicit    schedule   for
implementation  and  assessment.    States can
also  use the  phased  approach  to address a
greater  number   of water  bodies  including
threatened   waters  or watersheds  that  would
otherwise    not    be   managed.      Specific
requirements  relating to the phased approach
are discussed  in  Guidance  for Water Quality-
based Decisions:  The TMDL  Process (USEPA
1991c).
         Establish Source Controls
Once a TMDL has been established for a water
body (or watershed) and the appropriate  source
loads  developed,  implementation  of control
actions  should  proceed.  The State or EPA is
responsible  for implementation,  the  first  step
being to update the water quality management
plan. Next, point and nonpoint source controls
should  be implemented   to  meet  waste  load
allocations and load  allocations,  respectively.
Various  pollution  allocation   schemes   (i.e.,
determination   of  allowable   loading  from
different pollution  sources  in the same water
body) can  be  employed  by States to  optimize
alternative    point   and
management  strategies.
nonpoint   source
The NPDES  permitting process is used to limit
effluent  from  point  sources.   Section  7.6.1
provides a more complete description  of the
NPDES process and how  it fits into the water
quality-based   approach   to   permitting.
Construction  decisions regarding publicly owned
treatment  works (POTWs), including advanced
treatment  facilities,  must also be based  on the
more stringent  of  technology-based or water
quality-based  limitations.     These  decisions
should be coordinated so that the  facility plan
for  the  discharge   is  consistent   with  the
limitations  in the permit.

In the case of nonpoint sources, both State and
local laws may authorize  the implementation  of
nonpoint source controls such as the installation
of best management  practices  (BMPs) or other
management  measures.  CWA section 319 and
Coastal   Zone    Act   Reauthorization
Amendments  of 1990 (CZARA)  section  6217
State management    programs  may  also  be
utilized  to  implement  nonpoint source control
measures  and  practices  to  ensure  improved
water   quality.      Many  BMPs   may   be
implemented   through  section  319 programs
even where State regulatory programs  do not
exist. In such cases, a State needs to document
the coordination that may be  necessary  among
State and local agencies,  landowners, operators,
and   managers   and  then   evaluate   BMP
implementation,   maintenance,   and   overall
effectiveness  to ensure that load allocations are
achieved.   Section  7.6.2 discusses some of the
programs  associated   with implementation  of
nonpoint source control  measures.

States   may  also  grant,  condition, or  deny
"certification" for  a  federally  permitted   or
licensed activity that  may result in a discharge
to the waters of the  United  States, if it is the
State where  the discharge will originate.  The
State   decision  is   based   on   a   State's
determination of whether the  proposed  activity
will comply  with the  requirements  of  certain
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                                         Chapter 7 - The Water Quality-Based Approach to Pollution Control
 sections of  the  Clean  Water  Act,  including
 water  quality standards  under  section  303.
 Section 7.6.3 of this Handbook  contains further
 discussion  of section 401 certification.

 7.6.1     Point Source Control - the NPDES
          Process

 Both technology-based  and water quality-based
 controls are  implemented  through  the National
 Pollutant   Discharge    Elimination    System
 (NPDES)  permitting  process.  Permit limits
 based on TMDLs are called water quality-based
 limits.

 Waste  load  allocations  establish  the  level  of
 effluent quality  necessary  to  protect  water
 quality  in  the receiving water  and to ensure
 attainment   of water quality  standards.  Once
 allowable   loadings   have   been   developed
 through WLAs for specific pollution  sources,
 limits are incorporated  into NPDES permits.  It
 is important  to ensure that the WLA  accounts
 for the  fact that effluent quality is often highly
 variable. The WLA and permit  limit should be
 calculated  to prevent water  quality standards
 impairment at all times. The reader is referred
 to the  Technical Support Document for Water
 Quality-based Toxics Control (USEPA,  1991a)
 for additional  information on  deriving permit
 limits.

 As a result of the 1987 Amendments to the  Act,
 Individual   Control  Strategies  (ICSs)   were
 established  under section  304(1)(1) for certain
 point   source  discharges   of  priority   toxic
 pollutants.    ICSs  consist of NPDES  permit
 limits and  schedules  for achieving  such  limits,
 along with  documentation  showing that  the
 control  measures selected are appropriate  and
 adequate (e.g.,fact sheets including information
 on   how  water   quality-based  limits   were
 developed,  such as total maximum daily loads
 and  waste load allocations).  Point  sources with
approved ICSs are  to  be in compliance  with
those ICSs as  soon as possible or in  no case
later than 3 years from the establishment  of the
ICS  (typically by 1992 or 1993).
When  establishing WLAs for point sources in a
watershed, the TMDL record should show that,
in the case of any  credit for future  nonpoint
source  reductions   (1)  there   is  reasonable
assurance that nonpoint source  controls will be
implemented   and   maintained,  or  (2)   that
nonpoint  source reductions  are demonstrated
through   an  effective  monitoring   program.
Assurances  may  include  the  application  or
utilization of local ordinances, grant conditions,
or other  enforcement authorities.  For example,
it may be appropriate  to provide  that a permit
may be reopened when a WLA requiring more
stringent limits is necessary because attainment
of a nonpoint  source load allocation  was not
demonstrated.

7.6.2     Nonpoint  Source Controls

In  addition   to  permits  for  point   sources,
nonpoint  sources controls  such  as management
measures  or best management  practices (BMPs)
are  also  to  be implemented   so that  surface
water  quality  objectives  are  met.   To  fully
address water bodies impaired or threatened by
nonpoint   source   pollution,   States   should
implement their nonpoint  source management
programs   and  ensure  adoption   of  control
measures  or  practices  by all  contributors  of
nonpoint  source  pollution   to  the  targeted
watersheds.

Best management  practices  are the  primary
mechanism  in  section  319 of the  CWA to
enable achievement  of water quality standards.
Section 319 requires each  State, in addition to
developing the assessment reports  discussed in
section 7.2.1 of this Handbook,  to  adopt  NPS
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management    programs    to   control   NFS
pollution.

Sections  208(b)(2)(F) through (K) of the CWA
also require States  to set  forth procedures and
methods  including  land  use  requirements,  to
control to the extent feasible  nonpoint sources
of pollution reports.

Section   6217   of   the   Coastal   Zone
Reauthorization   Amendments   of   1990
(CZARA)  requires  that  States with  federally
approved coastal zone  management  programs
develop  Coastal  Nonpoint Pollution  Control
Programs to be approved  by EPA and NOAA.
EPA and NOAA have issued  Coastal Nonpoint
Pollution Control Program;ProgramDevelopment
and Approval Guidance  (NOAA/EPA,  1993),
which describes the program development and
approval  process  and requirements.    State
programs are  to  employ  an initial technology-
based  approach   generally  throughout   the
coastal management area, to  be followed by a
more stringent water quality-based approach to
address  known  water  quality problems.  The
Management   Measures generally implemented
throughout the coastal management  area are
described in Guidance  Specifying Management
Measures for  Sources of Nonpoint  Pollution in
Coastal  Waters (USEPA,  1993b).

7.6.3    CWA Section 401 Certification

States    may   grant,   condition,    or   deny
"certification"  for  a  federally  permitted  or
licensed  activity that may result in a discharge
to the waters  of the United States, if it is the
State where the  discharge  will originate.  The
language of section 401(a)(l) is very broad with
respect  to the activities it covers:

     [A]ny  activity,  including,  but   not
     limited   to,  the   construction    or
     operation  of facilities,  which  may
     result in any discharge . . .

requires  water quality certification.
EPA has identified  five Federal permits and/or
licenses that authorize activities that may result
in a discharge to the  waters:  permits  for point
source  discharge  under  section   402   and
discharge  of dredged and  fill material  under
section 404 of the Clean Water Act; permits for
activities in navigable  waters that may  affect
navigation  under  sections  9 and  10 of the
Rivers and Harbors  Act  (RHA); and licenses
required  for hydroelectric projects issued  under
the Federal  Power  Act. There are likely other
Federal permits  and  licenses, such as permits
for activities  on public  lands,  and  Nuclear
Regulatory  Commission  licenses,  which may
result  in  a discharge  and  thus require  401
certification.  Each  State should work with EPA
and the Federal  agencies active  in its State to
determine  whether 401 certification   is in fact
applicable.

Congress  intended  for the  States to use the
water quality certification  process to ensure that
no Federal license  or permits would  be  issued
that would violate State standards or become a
source  of pollution   in  the  future.      Also,
because   the    States'   certification    of   a
construction permit or license also operates as
certification for an operating  permit  (except in
certain instances  specified in section 401(a)(3)),
it is imperative  for a State review to consider
all potential  water   quality   impacts of the
project, both direct and indirect,  over the life of
the project.

In  addition,   when an activity  requiring  401
certification in one State  (i.e. the State in which
the discharge  originates) will have an impact on
the water quality of  another  State, the statute
provides   that   after   receiving   notice  of
application   from  a  Federal   permitting  or
licensing  agency, EPA will  notify any  States
whose water  quality  may  be affected.   Such
States have the  right to submit their  objections
and request a hearing.  EPA may also submit
its evaluation  and recommendations.   If the use
of conditions  cannot ensure compliance with
the affected State's water quality requirements,
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                                          Chapter 7 - Tlie Water Quality-Based Approach to Pollution Control
the Federal permitting or licensing agency shall
not issue such permit or license.

The  decision   to  grant,  condition,  or  deny
certification is based on a State's determination
from data submitted  by an applicant  (and any
other  information   available   to  the   State)
whether  the proposed  activity will comply with
the  requirements  of  certain  sections  of the
Clean  Water  Act  enumerated   in   section
401(a)(l).     These   requirements   address
effluent   limitations   for  conventional   and
nonconventional   pollutants,   water   quality
standards, new source performance  standards,
and toxic pollutants  (sections 301,302,303,306,
and 307).  Also included  are requirements  of
State  law or  regulation  more   stringent  than
those  sections  or their Federal  implementing
regulations.

States adopt   surface  water quality standards
pursuant  to section  303 of the Clean Water Act
and  have  broad   authority  to  base  those
standards on the waters' use and value for "...
public water supplies, propagation  of fish and
wildlife, recreational  purposes,  and  . .  . other
purposes"  (33  U.S.C. section 1313 (c)(2)(A)).
All permits must include effluent  limitations at
least   as  stringent   as  needed   to  maintain
established  beneficial  uses  and to attain  the
quality of water designated by States for their
waters.    Thus,  the   States'  water   quality
standards  are   a  critical  concern  of the  401
certification process.

If a State grants water quality certification to an
applicant for a Federal license or permit, it is in
effect  saying   that   the proposed  activity  will
comply with State water quality  standards  (and
the  other  CWA  and  State  law provisions
enumerated above).   The State  may thus  deny
certification  because  the  applicant  has  not
demonstrated  that the project will comply with
those requirements.   Or it may place whatever
limitations or conditions on the certification  it
determines  are necessary to ensure compliance
with  those provisions,  and  with  any  other
"appropriate" requirements of State law.
If a  State  denies  certification,  the  Federal
permitting  or licensing  agency is prohibited
from  issuing  a permit or  license.   While the
procedure varies  from State to State, a State's
decision  to  grant  or  deny   certification   is
ordinarily subject to an  administrative appeal,
with review in the State courts designated for
appeals  of  agency decisions.   Court  review  is
typically limited to the question of whether the
State   agency's decision  is supported by the
record and  is not arbitrary  or  capricious.  The
courts generally  presume  regularity  in agency
procedures  and  defer to  agency  expertise   in
their  review.  (If the  applicant is a  Federal
agency, however,  at least one Federal  court has
ruled that the State's certification decision may
be reviewed by the Federal courts.)

States    may   also   waive    water   quality
certification,    either   affirmatively   or
involuntarily.   Under  section 401(a)(l),  if the
State   fails  to act  on a certification  request
"within  a reasonable  time (which  shall  not
exceed  one  year)"  after   the  receipt  of  an
application,   it  forfeits its  authority  to  grant
conditionally or to deny  certification.

The  most important  regulatory tools for the
implementation  of 401  certification   are  the
States' water quality standards   regulations and
their 401 certification implementing regulations
and guidelines.  Most Tribes do not  yet have
water  quality standards,  and developing  them
would be  a  first  step  prior   to  having  the
authority to conduct water  quality certification.
Also, many  States have not adopted regulations
implementing  their authority to grant, deny, and
condition water quality certification.   Wetland
and   401  Certification:   Opportunities   and
Guidelines for States and Eligible Indian  Tribes
(USEPA, 1989a) discusses  specific  approaches,
and elements  of  water  quality standards and
401 certification regulations that EPA views as
effective to  implement  the  States' water quality
certification authority.
(9/15/93)
                                          7-11

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Water Quality Standards Handbook - Second Edition
         Monitor and Enforce Compliance
As  noted  throughout  the  previous  sections,
monitoring  is a  crucial  element   of water
quality-based  decision  making.    Monitoring
provides data  for  assessing compliance  with
water quality-based controls and for evaluating
whether the TMDL and control actions that are
based  on  the TMDL  protect  water  quality
standards.

With point sources, dischargers are required  to
provide reports on  compliance  with NPDES
permit  limits.   Their  discharge  monitoring
reports (DMR) provide  a key source of effluent
quality  data.   In  some instances,  dischargers
may also be required in  the permit to assess the
impact  of their  discharge on the  receiving
water.   A monitoring requirement  can be put
into the permit as a special condition  as long as
the  information is collected  for  purposes  of
writing a permit limit.

States   should  also  ensure  that  effective
monitoring programs are in place for evaluating
nonpoint  source  control   measures.    EPA
recognizes monitoring as a high-priority activity
in  a  State's   nonpoint  source  management
program (55 F.R. 35262, August 28,1990). To
facilitate the implementation  and evaluation  of
NFS  controls, States  should  consult  current
guidance  (USEPA,  1991g); (USEPA,  1993b).
States  are  also encouraged to use innovative
monitoring programs (e.g.,rapid bioassessments
(USEPA,   1989e),  and volunteer  monitoring
(USEPA,  1990b) to provide for adequate point
and nonpoint  source monitoring coverage.

Dischargers   are   monitored  to   determine
whether  or  not they  are meeting  their permit
conditions  and to ensure  that  expected water
quality improvements are achieved.  If a State
has  not  been  delegated   authority  for  the
NPDES permit program, compliance  reviews of
all   permittees   in   that   State   are   the
responsibility  of EPA.  EPA  retains oversight
responsibility  for State compliance programs in
NPDES-delegated  States. NPDES permits also
contain  self-monitoring  requirements  that  are
the responsibility of the individual discharger.
Data  obtained  through self-monitoring   are
reported  to the appropriate  regulatory agency.

Based  on  a review of data,  EPA or a State
regulatory  agency determines  whether or not a
NPDES  permittee   has complied   with  the
requirements  of the  NPDES  permit.    If  a
facility has been identified as having apparent
violations,  EPA or the  State  will review  the
facility's compliance  history.   This   review
focuses   on  the  magnitude,   frequency,  and
duration  of violations.  A determination  of the
appropriate  enforcement  response is then made.
EPA and States  are authorized to bring civil or
criminal  action  against  facilities that  violate
their NPDES permits.   State nonpoint  source
programs are enforced under State law  and to
the extent provided by State  law.

Once control measures  have been implemented,
the impaired waters  should  be assessed  to
determine  if water quality standards  have been
attained  or  are no longer  threatened.    The
monitoring program used to gather the data for
this assessment  should  be designed  based on
the specific pollution problems or sources. For
example, it is difficult to ensure, a priori, that
implementing nonpoint  source  controls   will
achieve  expected   load reductions  due  to
inadequate   selection of  practices or  measures,
inadequate  design or implementation,  or lack of
full participation  by all  contributing  nonpoint
sources  (USEPA,   1987e).   As a result, long-
7-12
                                      (9/15/93)

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                                          Chapter 7 - The Water Quality-Based Approach to Pollution Control
term monitoring  efforts must be consistent over
time  to develop  a data  base  adequate  for
analysis of control actions.
          Measure Progress
If the water body achieves  the applicable State
water quality standards, the water body may be
removed  from  the 303 (d)  list  of waters  still
needing TMDLs.  If the water quality standards
are not met, the TMDL and allocations of load
and  waste  loads  must  be modified.    This
modification  should be based on the additional
data and  information   gathered  as required  by
the phased approach  for developing  a TMDL,
where  appropriate;   as   part   of  routine
monitoring  activities;   and  when assessing  the
water   body   for  water   quality   standards
attainment.
(9/15/93)                                                                                    7-13

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       REFERENCES
                               n
                               w
                               05
WATER QUALITY STANDARDS HANDBOOK




        SECOND EDITION

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                                                                                 References
                                    REFERENCES
Barnes, D.G., and M. Dourson.  1988. Reference Dose (RfD): Description and Use in Health Risk
     Assessments. Regulatory Toxicology and Pharmacology 8, 471-486.

Brungs, W.A. 1986.  Allocated Impact Zones for Areas of Non-Compliance.  USEPA, Region 1.
     Water Management Division, Boston, MA.  (Source #3.)

Cole, G.A.  1979. Textbook of Limnology.  The C.V. Mosby Co.  St. Louis MO

Erickson, R., C. Kleiner, J. Fiandt, and T. Hignland.  1989. Report on the Feasibility of
     Predicting the Effects of Fluctuating Concentrations on Aquatic Organisms.  USEPA, ERL,
     Duluth, MN.  (Source #16.)

FVVPCA (Federal Water Pollution Control Administration).  1968.  Water Quality Criteria (the
     "Green Book"), Report of the National Technical  Advisory Committee to the Secretary of the
     Interior.  U.S. Department of the Interior, Washington, DC.  (Out of Print.)

GAO (U.S. General Accounting Office) 1987. Wildlife Management; National Refuge
     Contamination is Difficult to Confirm and Clean Up.  Report to the Chairman, Subcommittee
     on Oversight and Investigations, Committee on Energy and Commerce, House of
     Representatives.   Washington, DC.  GAO/RCED-87-128. (Source #6.)

ITFM. 1992. Ambient Water-quality Monitoring in the United States: First Year Review,
     Evaluation,  and Recommendations.  Intergovernmental Task Force on Monitoring Water
     Quality. Washington, DC.  (Source #15.)

Karr, J.R.  1981. Assessment of Biotic Integrity  Using Fish  Communities.   Fisheries, Vol. 6, No.6,
     pp. 21-27.

Mancini, J.L.  1983.  A Method for Calculating Effects on Aquatic Organisms of Time-Varying
     Concentrations.  Water Res. 17:1355-61.

McLusky,  D.S.  1971.  Ecology of Estuaries.  Heinemann Educational Books, Ltd.  London.

NAS/NAE.  1973. Water Quality Criteria 1972 (the "Blue Book"), a Report of the Committee on
     Water Quality Criteria. National Academy of Science and National Academy of Engineering,
     Washington, DC. NTIS-PB 236199.  USGPO #5501-00520.  (Source #2 or #7.)

NO A A/EPA. 1993.  Coastal Nonpoint Pollution Control Program; Program Development and
     Approval Guidance. National  Oceanic and Atmospheric Administration and Environmental
     Protection Agency, Washington, DC. (Source #8.)

Rossman, Lewis J. 1990. Design Stream Flows Based on Harmonic Means.  L of Hydraulics
     Engineering, Vol. 116, No. 7.


   (9/15/93)                                                                     REF-1

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Water Quality Standards Handbook - Second Edition
Thomann, R.V.  1987.  A Statistical Model of Environmental Contaminants Using Variance
     Spectrum Analysis.  Report to National Science Foundation.  NTIS #PB 88-2351307A09.
     (Source #2.)

Thomann, R.V.  1989.  Bioaccumulation Model of Organic Chemical Distribution in Aquatic Food
     Chains.  Environ. Sci. Technol. 23: 699-707.

U.S. Department of Agriculture.  1984.  Agricultural Statistics.  USD A, Washington, DC. p. 506.

USEPA (U. S. Environmental Protection Agency). 1972.  Biological Field and Laboratory Methods
    for Measuring the Quality of Surface Waters and Effluents.  Office of Research and
     Development, Washington, DC.  EPA 670/4-73-001.  (Source #9.)

	. 1976.  Quality Criteria for Water 1976 (the "Red Book").  Office of Water and Hazardous
     Materials, Washington, DC.  GPO #055-001-01049-4. (Source #7.)

    	. 1980a. Notice of Water Quality Criteria Documents.  Criteria and Standards Division,
     Washington, DC.  45 F.R. 79318, November 28, 1980.

    	. 1980b. Guidelines and  Methodology Used in the Preparation of Health Effects Assessment
     Chapters of the Consent Decree Water Documents.  Criteria and Standards Division,
     Washington, DC.  45 F.R. 79347, November 28, 1980.

    	. 1980c. Seafood Consumption Data Analysis.  Stanford Research Institute International,
     Menlo Park, CA.  Final Report, Task 11, Contract No. 68-01-3887.  Office of Water
     Regulations and Standards, Washington, DC.  (Source #10.)

    	. 1981. Notice of Water Quality Criteria Documents.  Criteria and Standards Division,
     Washington, DC.  46 F.R. 40919, August 13,  1981.

    	. 1983a. Water Quality Standards Handbook.  Office of Water Regulations and Standards,
     Washington, DC.  (Out of Print.)

    	. 1983b. Methods for Chemical Analysis of Water and Wastes (Sections 4.1.1,  4.1.3, and
     4.1.4).  Environmental Monitoring and Support Laboratory, Cincinnati, OH.  EPA 600/4-79-
     020.  (Source #9.)

    	. 1983c. Technical Support Manual: Waterbody Surveys and Assessments for Conducting
     Use Attainabilty Analyses, Volume J.  Criteria and Standards Division, Washington, DC.
     (Source #10.)

    	. 1983d. Technical Guidance Manual for Performing Waste Load Allocations - Book II
     Streams and Rivers - Chapter 1 Biochemical Oxygen Demand/Dissolved Oxygen.  Monitoring
     and Data Support Division, Washington, DC.  EPA 440/4-84-020.  (Source #10.)

   	. 1983e.  Technical Guidance Manual for Performing Waste Load Allocations - Book II
     Streams and Rivers - Chapter 2 Nutrient/Eutrophication Impacts. Monitoring and Data Support
     Division, Washington, DC.  EPA 440/4-84-021. (Source #10.)


   REF-2                                                                       (9/15/93)

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                                                                                 References

  	. 1983f. Technical Guidance Manual for Performing Waste Load Allocations - Book IV
  Lakes and Impoundments - Chapter 2 Nutrient/Eutrophication Impacts.  Monitoring and Data
  Support Division, Washington, DC.  EPA 440/4-84-019.  (Source #10.)

  	. 1984a. Technical Support Manual: Waterbody Surveys and Assessments for Conducting
  Use Attainability Analyses, Volume II, Estuarine Systems.  Criteria and Standards Division,
  Washington, DC.  (Source #10.)

  	. 1984b. Technical Support Manual: Waterbody Surveys and Assessments for Conducting
   Use Attainability Analyses,  Volume III, Lake Systems.  Criteria and Standards Division,
   Washington, DC.  (Source #10.)

  	. 1984d. State Water Quality Standards Approvals: Use Attainability  Analysis Submittals.
   (Memorandum from Director, Criteria and Standards Division to Director, Water Management
   Division, Region I; November 28.) Washington, DC.   (Source #11.)

  	. 1984e. Technical Guidance Manual for Performing Waste Load Allocations.  Book II
  Streams and Rivers.  Chapter 3 Toxic Substances.  Office of Water Regulations and Standards,
  Washington, DC.  EPA 440/4-84-022.  (Source #10.)

  	. 1985a. Methods for Measuring Acute Toxicity of Effluents to Freshwater and Marine
  Organisms. Office of Research and Development. Washington, DC.  EPA 600-4-85-013.
  (Source #9.)

  	. 1985b. Guidelines for Deriving National Water Quality Criteria for the Protection of
  Aquatic Organisms and Their Uses.  Office of Water Regulations and Standards, Washington,
  DC.  45 F.R. 79341, November 28, 1980, as amended at 50 F.R. 30784, July 29,  1985.
  NTIS #PB 85-227049.  (Source #2.)

  	. 1985c. Short-Term Methods for Estimating the Chronic Toxicity of Effluents and
  Receiving Waters to Freshwater Organisms.  Office of Research and Development,  Cincinnati,
  OH. EPA 600-4-85-0145.

     . 1985d.  Guidance for State Water Monitoring and Waste Load Allocation Programs.
  Office of Water Regulations and Standards.  Washington, DC.  EPA 440/4-85-031.  (Out of
  Print.)

 	.  1985e.  Interpretation of the Term "Existing Use". (Memorandum from Director, Criteria
  and Standards Division to Water Quality Standards Coordinator, Region IV; February 21.)
  Washington, DC.   (Source #11.)

     .  1985f.  Selection of Water Quality Criteria in State Water Quality Standards.
  (Memorandum from Director, Office of Water Regulations and Standards to Water Division
  Directors, Region I - X; February 28.) Washington, DC.  (Source #11.)

	.  1985g.  Variances in Water Quality Standards.  (Memorandum from Director, Office of
  Water Regulations and Standards to Water Division Directors; March 15.) Washington, DC.
  (Source #11.)

 (9/15/93)                                                                        REF-3

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Water Quality Standards Handbook - Second Edition
    	. 1985h. Antidegradation, Waste Loads, and Permits.  (Memorandum from Director,
     Office of Water Regulations and Standards to Water Management Division Directors, Region I
     -X.)  Washington, DC.  (Source #11.)
        . 1985i.  Antidegradation Policy.  (Memorandum from Director, Criteria and Standards
     Division to Water Management Division Directors,  Region I - X; November 22.)
     Washington, DC.  (Source #11.)

    	. 1986a. Quality Criteria for Water (the "Gold Book") Office of Water Regulations and
     Standards, Washington DC.  EPA 440/5-86-001.  USGPO #955-002-00000-8.  (Source #7.)

    	. 1986b. Ambient Water Quality Criteria for Bacteria.  Office of Water Regulations and
     Standards, Washington DC.   EPA 440/5-84-002. PB 86-158045. (Source #2.)

    	. 1986c.  Technical Guidance Manual for Performing Waste Load Allocations, Book 6,
     Design Conditions. Office of Water Regulations and Standards, Washington, DC. EPA 440/4-
     87-002.  (Source #10.)

    	. 1986d.  Technical Guidance Manual for Performing Waste Load Allocations, Book VI,
     Design Conditions: Chapter 1 - Stream Design Flow for Steady-State Modeling. Office of
     Water Regulations and Standards, Washington, DC. EPA 440/4-87-004.  (Source #10.)

    	. 1986e.  Answers to Questions on Nonpoint Sources and WQS.  (Memorandum from
     Assistant Administrator for Water to Water Division Director, Region X; March 7.)
     Washington, DC.  (Source #11.)

    	. 1986f.  Determination of "Existing Uses" for Purposes of Water Quality Standards
     Implementation. (Memorandum from Director, Criteria and Standards Division to Water
     Management Division Directors, Region I - X, WQS Coordinators, Region I - X; April 7.)
     Washington, DC.  (Source #11.)

    	. 1987d.  Nonpoint Source Controls and Water Quality Standards.  (Memorandum from
     Chief, Nonpoint Source Branch to Regional Water  Quality Branch Chiefs; August 19.)
     Washington, DC.  (Source #11.)

        . 1987e.  Setting Priorities:  The Key to Nonpoint Source Control.  Office of Water
     Regulations and Standards. Washington, DC. (Source #8.)

    	. 1988a.  Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving
     Waters to Marine and Estuarine Organisms.  Office of Research and Development, Cincinnati,
     OH.  EPA 600/4-87-028.

        . 1988d.  State Clean Water Strategies; Meeting the Challenges for the Future.  Office of
     Water. Washington, DC.  (Source #5.)

    	.  1988e.  Guidance for State Implementation of Water Quality Standards for CWA Section
     303(c)(2)(B). Office of Water. Washington, DC. (Source #10.)
    REF-4                                                                        (9/15/93)

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                                                                                References
     . 1989a. Wetlands and 401 Certification: Opportunities for States and Eligible Indian
  Tribes.  Office of Wetlands Protection, Washington, DC.  (Source #12.)

 	. 1989b. Exposure Factors Handbook.  Office of Health and Environmental Assessment,
 "Washington, DC.  EPA 600/8-89-043. (Source #9.)

 	. 1989c. Application of Antidegradation Policy to the Niagara River.  (Memorandum from
  Director, Office of Water Regulations and Standards to Director, Water Management Division,
  Region II;  August  4.) Washington, DC.  (Source #11.)

 	. 1989d. Selecting Priority Nonpoint Source Projects:  You Better Shop Around.  Office of
  Water; and Office  of Policy, Planning and Evaluation. Washington, DC.  EPA 506/2-89-003.
  (Source #13.)

 	. 1989e. Rapid Bioassessment Protocols for Use in Streams and Rivers.  Assessment and
 Watershed Protection Division.  Washington, DC.  EPA 444/4-89-001.  (Source #14.)

 	. 1989f. EPA Designation of Outstanding National Resource Waters.  (Memorandum from
 Acting Director, Criteria and Standards Division to Regional Water Management Division
 Directors; May 25.)  Washington, DC.  (Source #11.)

 	. 1989g.  Guidance for the Use of Conditional Approvals for State WQS.  (Memorandum
  from Director, Office of Water Regulations and Standards to Water Division Directors,
  Regions I - X; June 20.) Washington, DC.  (Source #11.)

 	. 1989h. Designation of Recreation Uses.  (Memorandum from Director, Criteria and
  Standards Division to Director, Water Management Division, Region IV; September 7.)
  Washington, DC.  (Source #11.)

 	. 1989i.  Water Quality Criteria to Protect  Wildlife Resources.  Environmental Research
 Laboratory. Corvallis, OR.  EPA 600/3-89-067.  NTIS #PB 89-220016. (Source #2.)

 	. 1989j.  Assessing Human Health Risks from Chemically Contaminated Fish and Shellfish:
 a Guidance Manual. Office of Water Regulations and Standards. Washington, DC.  EPA
 503/8-89-002.  (Source #10.)

 	. 1990a. Biological Criteria, National Program Guidance for Surface Waters.  Office of
 Water Regulations and Standards, Washington, DC. EPA 440/5-90-004. (Source #10)

 	. 1990b.  Volunteer Water Monitoring: A Guide for State Managers.  Office of Water.
 Washington, DC.  EPA 440/4-90-010. (Source #14.)

 	. 1990c. The Lake and Reservoir Restoration Guidance Manual, Second Edition.  Office of
 Water.  Nonpoint Source Branch.  Washington, DC.  EPA 440/4-90-006.  (Source #14.)

 	. 1991a. Technical Support Document for Water Quality-based Toxics Control.  Office of
 Water, Washington, DC. EPA 505/2-90-001.  NTIS #PB 91-127415.  (Source #2.)
(9/15/93)                                                                       REF-5

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Water Quality Standards Handbook - Second Edition
        . 199 lb.  Methods for the Determination of Metals in Environmental Samples.
     Environmental Monitoring Systems Laboratory, Cincinnati, OH 45268.  EPA 600/4-91-010.
     (Source #9.)

    	. 1991c.  Guidance for Water Quality-based Decisions: The TMDL Process.  Office of
     Water, Washington, DC.  EPA 440/4-91-001  (Source #14.)

    	. 1991d.  Methods for Measuring the Acute Toxicity of Effluents to Aquatic Organisms. 4th.
     ed.  Office of Research  and Development. Cincinnati, OH.  EPA 600/4-90-027.  (Source #9.)

    	. 199 le.  Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving
     Waters to Freshwater Organisms.  3d. ed. Office of Research and Development, Cincinnati,
     OH.  EPA 600/4-91-002. (Source #9.)

    	. 199 If.  Short-term  Methods for Estimating the Chronic Toxicity of Effluents and Receiving
     Waters to Marine and Estuarine Organisms. 2d. ed. Office of Research and Development,
     Cincinnati, OH.  EPA 600/4-91-003.  (Source #9.)

    	. 199Ig.  Watershed Monitoring and Reporting Requirements for Section 319 National
     Monitoring Program Projects. Assessment and Watershed Protection Division.  Washington
     DC.  (Source #8.)

    	. 1991h.  Section 401 Certification and FERC Licenses.  (Memorandum from Assistant
     Administrator, Office of Water to Secretary, Federal Energy Regulatory Commission; January
     18.)  Washington, DC.  (Source #11.)

    	.  1991i. Policy on the Use of Biological Assessments and Criteria in the Water Quality
     Program.  (Memorandum from Director. Office of Science and Technology to Water
     Management Division Directors, Regions I - X; June 19.)  (Source #4.)

    	.  1993a.  Guidelines for Preparation of the 1994 State Water Quality Assessments 305(b)
     Reports.  Office of Wetlands, Oceans and Watersheds. Washington, DC. (Source #14.)

    	. 1993b.  Guidance Specifying Management Measures for Sources ofNonpoint Pollution in
     Coastal Waters.  Office of Water.  Washington, DC.  840-B-92-002. (Source #8.)

    	. 1993c.  Geographic Targeting: Selected State Examples.  Office of Water.  Washington,
     DC.  EPA 841-B-93-001.  (Source #14.)

    	.  1993d.  Final Guidance on the Award and Management ofNonpoint Source Program
     Implementation Grants Under Section 319(h) of the Clean Water Act for Fiscal Year 1994 and
     Future Years. Office of Water.  Washington, DC.  (Source #8.)

    	.  1993e.  Guidance for Assessing Chemical Contaminant Data for Use in Fish Advisories;
     Volume 1 - Fish Sampling and Analysis (in preparation).  Office of Water. Washington, DC.
     EPA 823-R-93-002.  (Source #9.)
    REF-6                                                                        (9/15/93)

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                                                                                    References

Vernberg, W.B.  1983.  Responses to Estuarine Stress.  In: Ecosystems of the World: Estuaries and
     Enclosed Seas,  B.H. Ketchum,  ed.  Elsevier Scientific Publishing Company, New York, pp.
     43-63.

Versar.  1984.  Draft Assessment of International Mixing Zone Policies.  Avoidance/Attraction
     Characteristics, and Available Prediction Techniques.  USEPA, Office of Water Regulations
     and Standards and USEPA Office of Pesticides and Toxic Substances, Washington, DC.
   (9/15/93)                                                                         REF-7

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Water Quality Standards Handbook - Second Edition
                            SOURCES OF DOCUMENTS
(1)  Seth Ausubel
    U.S. Environmental Protection Agency
    Region 2
    26 Federal Plaza
    New York, NY 10278
    Ph: (212) 264-6779

(2)  National Technical Information Center
    (NTIS)
    5285 Front Royal Road
    Springfield, VA 22161
    Ph:  (703)487-4650

(3)  U. S. Environmental Protection Agency
    Region 1
    Water Quality Standards Coordinator
    Water Division
    JFK Federal Building
    One Congress Street
    Boston, MA 02203
    Ph: (617) 565-3533

(4)  U. S. Environmental Protection Agency
    Health and Ecological Criteria Division
    401 M Street, S.W.
    Mail Code 4304
    Washington, DC 20460
    Ph:  (202)260-5389
    (See Appendix V)

(5)  U. S. Environmental Protection Agency
    Office of Water
    401 M Street, S.W.
    Mail Code 4101
    Washington, DC 20460
    Ph:  (202)260-5700
(6)  U.S. General Accounting Office
    Post Office Box 6015
    Gaithersburg, MD 20877
    Telephone: 202-512-6000
    (First copy free)

(7)  U.S. Government Printing Office
    Superintendent of Documents
    North Capitol Street H Streets, NW
    Washington, DC 20401
    Ph: (202) 783-3238

(8)  U. S. Environmental Protection Agency
    Nonpoint Source Control Branch
    401 M Street, S.W.
    Mail Code 4503
    Washington, DC 20460
    Ph: (202) 260-7100

(9)  U.S. Environmental Protection Agency
    Center for Environmental Research
    Office of Research and Development
    Room G72
    26 West Martin Luther King Drive
    Cincinnati,  OH 45268
    Ph: (513) 569-7562

(10) U. S. Environmental Protection Agency
    Office of Water Resource Center
    Mail Code RC-4100
    401 M Street, S.W.
    Washington, DC 20460
    Ph:  (202) 260-7786 (voice mail
    publication request line)
    (See Appendix  V)
   REF-8
                               (9/15/93)

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                                                                                References
(11) U. S. Environmental Protection Agency
    Standards and Applied Science Division
    401 M Street, S.W.
    Mail Code 4305
    Washington, DC 20460
    Fax: (202) 260-9830
    Ph:  (202)260-7301
    (See Appendix V)

(12) U. S. Environmental Protection Agency
    Wetlands Division
    401 M Street, S.W.
    Mail Code 4502F
    Washington, DC 20460
    Ph:  (202)260-7719

(13) EPIC
    U. S. Environmental Protection Agency
    11029 Kenwood Road
    Building 5
    Cincinnati, OH 45242
    Fax: (513) 569-7186
    Ph:  (513)569-7980

(14) U. S. Environmental Protection Agency
    Assessment and Watershed Protection
    Division
    401 M Street, S.W.
    Mail Code 4503
    Washington, DC 20460
    Ph: (202)  260-7166
   (9/15/93)                                                                      REF-9

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         APPENDIX A
    Water Quality Standards Regulation
WATER QUALITY STANDARDS HANDBOOK

          SECOND EDITION
                                    I
                                    p i
                                    X

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                                                                    Appendix A - Water Quality Standards Regulation
                                   Water Quality Standards Regulation
                (40 CFR 131; 48 FR 51405, Nov. 8,1983; Revised through July 1,1991; amended
           56 FR 64893, Dec. 12,  1991; 57 FR 60910, Dec. 22, 1992)
      TITLE 40—PROTECTION
        OF ENVIRONMENT

  CHAPTER I—ENVIRONMENTAL
       PROTECTION AGENCY

     SUBCHAPTER D—WATER
             PROGRAMS

    PART 131—WATER QUALITY
            STANDARDS
  Authority: 33 U.S.C. 1251 et seq.

[Amended  at  56  FR  64893,  Dec. 12,
1991; 57 FR 60910, Dec. 22, 1992]

Subparl A—General Provisions
Sec.
131.1     Scope
131.2     Purpose.
131.3     Definitions.
131.4     Stale authority.
131.5     EPA authority.
131 6     Minimum requirements for water
          quality standards submission.
131.7     Dispute resolution mechanism.
131.8     Requirements Tor Indian Tribes to be
          treated as States for purposes of
          water quality standards.

Subpart B—Establishment of Water Quality
  Standards
131.10    Designation of uses.
131.11    Criteria.
131.12    Anlidegradation policy.
131.13    General policies.

Subpart C—Procedures for Review and Revision
  of Water Quality Standards
131.20    State review and revision of water
          quality standards.
131.21    EPA review and approval of water
          quality standards.
131.22    EPA promulgation of water quality
          standards.
Subpart D—Federally Promulgated Water Quali-
  ty Standards
131.31    An/X)na.
131.33— 131.34 [Reserved)
131 35    Colville Confederated Tribes Indian
           Reservatioi
                             c,
• 3/.V.

   Subpart A—General Provisions

§131.1 Scope.
  This  part describes the requirements
and procedures for developing, reviewing,
revising and approving water quality stan-
dards by the States as authorized by sec-
tion 303(c) of the Clean Water Act. The
reporting or recordkeeping (information)
provisions in  this rule were approved by
the Office of Management and Budget un-
der 3504(b) of the Paperwork Reduction
Act of 1980, U.S.C. 3501 et seq. (Approv-
al number  2040-0049).

§131.2 Purpose.
  A water quality  standard defines  the
water quality  goals of a water body, or
portion thereof, by designating the use or
uses to be made of the water and by  set-
ting criteria necessary to protect the uses.
States adopt water quality standards to
protect public health or welfare, enhance
the quality of  water  and  serve  the  pur-
poses of the Clean Water Act (the Act).
"Serve  the purposes of  the  Act" (as de-
fined  in sections 10l(a)(2) and 303(c) of
the Act) means that  water quality stan-
dards should, wherever attainable,  pro-
vide water  quality for the protection and
propagation of fish, shellfish and  wildlife
and for recreation in and on the water and
take into consideration their use and value
of public water supplies,  propagation of
fish, shellfish,  and wildlife,  recreation in
and on the  water, and agricultural, indus-
trial, and other purposes including naviga-
tion.
Such standards serve the dual purposes of
establishing the water quality goals for a
specific water body and serve as the regu-
       basis for the establishment of wa-
ter-quality-based treatment  controls and
strategies beyond  the technology-based
levels of treatment required by sections
301 (b) and 306 of the Act.

§131.3 Definitions.

  (a) The Act  means  the  Clean  Water
Act (Pub.  L.  92-500 , as amended, (33
U.S.C. 1251 el seq.)).
  (b) Criteria are elements of State water
quality standards,  expressed as  constitu-
ent concentrations,  levels,  or  narrative
statements, representing a quality  of wa-
ter  that supports a particular use.  When
criteria are met, water quality will  gener-
ally protect the designated use.
  (c) Section  304(a)  criteria are  devel-
oped  by  EPA under authority of section
304(a) of the Act based on the  latest sci-
entific information  on the  relationship
that the effect of a constituent concentra-
tion has on  particular aquatic species
and/or human health. This information is
issued periodically to the States as guid-
ance for  use in developing criteria.
  (d) Toxic pollutants are those  pollu-
tants listed by the Administrator  under
section 307(a) of the Act.
  (e) Existing uses are those uses actual-
ly attained in  the water body on or after
November  28, 1975, whether or not they
are included in the water  quality stan-
dards.
  (0 Designated uses are those  uses spec-
ified in water quality standards for each
       (9/14/93)

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water body  or segment  whether or not
they are being attained.
  (g) Use attainability analysis is a struc-
tured scientific assessment of the factors
affecting the attainment of the use which
may include  physical, chemical, biologi-
cal, and economic factors as described in
§131.IO(g).
  (h) Water quality  limited segment
means any segment where it is known that
water quality does  not  meet  applicable
water quality standards, and/or is not ex-
pected to meet applicable water quality
standards, even after the application of
the technology-bases  effluent  limitations
required  by sections  301(b) and 306 of
the Act.
  (i)  Water  quality standards are provi-
sions  of Stale or Federal law which con-
sist of a designated use or  uses for the
waters of the  United States  and water
quality criteria for such waters based up-
on such uses.. Water quality standards are
to protect Ihe  public health or  welfare,
enhance  the  quality of water and  serve
the purposes of the  Act.
[§131.3(j)—(1) added at 56 FR 64893,
Dec.  12, 1991]
  (j)  States include: The 50 States, the
District of Columbia, Guam, the  Com-
monwealth of Puerto Rico, Virgin Islands,
American Samoa, the Trust Territory of
the Pacific Islands, the Commonwealth of
the Northern  Mariana Islands, and Indi-
an  Tribes that EPA determines qualify
for treatment as States for purposes of
water quality standards.
  (k) Federal Indian Reservation, Indian
Reservation, or Reservation  means  all
land within the limits of any Indian reser-
vation under the jurisdiction of the United
States Government, notwithstanding the
issuance of  any patent, and  including
rights-of-way running through the  reser-
vation."
  (1) Indian Tribe or Tribe means any In-
dian  Tribe, band, group, or community
recognized by the Secretary of the Interi-
or and exercising governmental authority
over a Federal Indian reservation.

§131.4 State authority.
  (a) States (as defined in §131.3) are re-
sponsible for reviewing, establishing, and
revising water  quality standards. As rec-
ognized by section 510 of the Clean Wa-
ter Act, States may develop water quality
standards more stringent than required by
this regulation. Consistent  with section
101 (g) and  518(a) of the Clean Water
Act,  water quality standards shall not be
construed to superseder or abrogate rights
to quantities of water.
  (b) States (as defined  in §131.3) may
issue certifications pursuant to the  re-
quirements of Clean  Water Act section
401.  Revisions adopted by States shall be
applicable for use in issuing State certifi-
cations consistent  with the provisions of
§131.21(c).
  (c) Where EPA  determines that a
Tribe qualifies  for  treatment as a State
for purposes of water quality  standards,
the Tribe likewise qualifies for treatment
as a State for  purposes  of certifications
conducted under Clean Water Act section
401.
[§131.4 revised at 56  FR 64893, Dec.  12,
1991]

§131.5 EPA authority.

[§131.5  former paragraphs (a)—(e)  re-
designated as new (a) and (a)(l)—(a)(5)
at 56 FR 64893, Dec. 12, 1991]
   (a) Under section 303(c) of the Act,
EPA is to review and  to approve or disap-
prove State-adopted water quality stan-
dards. The review  involves a determina-
tion  of:
   (1) Whether  the State  has adopted wa-
ter uses which are consistent with the re-
quirements of the Clean  Water Act;
   (2) Whether  the state  has adopted  cri-
teria that protect  the designated water
uses;
   (3) Whether  the State has followed its
legal procedures for revising or adopting
standards;
   (4) Whether  the State  standards which
do not include the uses specified in section
101(a)(2) of the Act are based  upon  ap-
propriate technical and scientific data and
analyses, and
   (5) Whether  the  State submission
meets the  requirements  included  in
§131.6 of this  part.  If EPA determines
that State water quality  standards  are
consistent  with the  factors  listed  in
paragraphs (a)  through (e) of this section,
EPA approves  the standards.  EPA must
disapprove the  State water quality stan-
dards under section 303(c)(4) of the Act,
if State adopted standards are not consis-
tent  with the factors listed in paragraphs
(a) through (e) of this section.  EPA may
also  promulgate a new or revised standard
where necessary to meet the requirements
of the Act.
  (b) Section 401 of the Clean Water Act
authorizes EPA to issue certifications pur-
suant to the requirements of section 401
in any case where a State or interstate
agency has no authority for issuing such
certifications.

[§131.5(b) added  at 56  FR 64893, Dec.
12, 1991]

§131.6 Minimum  requirements  for  water
  quality standards submission.

  The following elements must be includ-
ed in each State's water quality standards
submitted to  EPA for review:
  (a) Use designations consistent with the
provisions of  sections  101(a)(2) and
303(c)(2) of the Act.
  (b) Methods used  and  analyses con-
ducted to support water quality standards
revisions.
  (c) Water quality criteria sufficient to
protect the designated uses.
  (d) An antidegradation  policy consis-
tent with §131.12.
  (e) Certification by the State Attorney
General or other appropriate legal author-
ity within the State that the water quality
standards were duly adopted pursuant to
State law.
  (f) General information which will aid
the Agency in determining the adequacy
of the  scientific  basis  of  the  standards
which  do not include the uses specified in
section 101(a)(2) of the Act as well as
information on general policies applicable
to State standards which may affect their
application and implementation.

§131.7 Dispute resolution mechanism.

   (a) Where disputes between States and
Indian Tribes arise as a result of differing
water  quality standards on common bod-
ies of water, the  lead EPA Regional Ad-
ministrator,  as  determined  based  upon
OMB circular A-105, shall be responsible
for acting  in accordance with the  provi-
sions of this section.
   (b) The  Regional Administrator shall
attempt to resolve such disputes where:
   (l)The difference in water quality
standards results  in unreasonable  conse-
quences;
   (2) The dispute is between  a State (as
defined in §131.30) but exclusive  of all
Indian Tribes) and a Tribe which EPA
has determined qualifies to be treated as a
State  for purposes of water quality stan-
dards;

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   (3) A reasonable effort to resolve the
 dispute  without EPA involvement has
 been made;
   (4) The requested relief  is consistent
 with the provisions of the  Clean Water
 Act and other relevant law;
   (5) The differing State and Tribal wa-
 ter quality standards have  been adopted
 pursuant to State and Tribal law and ap-
 proved  by EPA: and
   (6) A valid  written  request  has  been
 submitted by  either  the Tribe  or the
 State.
   (c) Either  a  State  or a Tribe may  re-
 quest EPA to  resolve any dispute which
 satisfies the  criteria of paragraph (b) of
 this section. Written requests for EPA in-
 volvement should be submitted to the lead
 Regional  Administrator and  must  in-
 clude:
   (1) A concise statement of the unrea-
 sonable  consequences that are alleged to
 have arisen  because of  differing water
 quality standards;
   (2) A concise description of the actions
 which have been taken to resolve the dis-
 pute without EPA  involvement;
   (3) A concise  indication  of the water
 quality standards provision which has  re-
 sulted in the alleged unreasonable conse-
 quences;
   (4) Factual data  to support the  alleged
 unreasonable consequences; and
   (5) A statement of  the  relief  sought
 from the alleged  unreasonable  conse-
 quences.
   (d) Where, in the Regional Administra-
 tor's judgment, EPA involvement is ap-
 propriate based on the factors of para-
 graph  (b) of this  section, the  Regional
 Administrator shall, within 30 days, noti-
 fy the parties  in writing that he/she is
 initiating an  EPA  dispute resolution ac-
 tion and solicit their written response. The
 Regional Administrator shall also make
 reasonable efforts to ensure that other  in-
 terested  individuals or groups have notice
 of this action. Such efforts  shall include
 but not be limited to the following:
   (1) Written notice to responsible Tribal
 and  State Agencies,  and other affected
 Federal Agencies,
   (2) Notice  to the specific  individual  or
 entity that is alleging that an unreason-
 able consequence is resulting from differ-
 ing standards having been adopted  on a
common body of water,
   (3) Public  notice in local  newspapers,
radio, and  television, as appropriate,
   (4) Publication  in  trade journal news-
 letters, and
   (5) Other means as appropriate.
   (e) If in accordance with  applicable
 State and Tribal law  an Indian Tribe and
 State have entered into an agreement that
 resolves the dispute or establishes a mech-
 anism for  resolving u dispute,  EPA shall
 defer to this agreement where it is consis-
 tent with the Clean Water Act and where
 it has been approved  by EPA.
   (0 EPA dispute resolution actions shall
 be consistent with  one or a combination of
 the following options:
   (1) Mediation. The Regional Adminis-
 trator may appoint a  mediator  to mediate
 the dispute. Mediators shall  be EPA em-
 ployees, employees  from  other Federal
 agencies, or other individuals with appro-
 priate qualifications.
   (i) Where the State and Tribe agree to
 participate in the dispute  resolution  pro-
 cess,  mediation with  the intent to estab-
 lish  Tribal-State  agreements,  consistent
 with  Clean  Water  Act section  5I8(d)
 shall normally be pursued as a  first effort.
   (ii) Mediators  shall act as  neutral
 facilitators whose function is  to encourage
 communication  and  negotiation  between
 all parties  to the dispute.
   (iii) Mediators may  establish advisory
 panels, to  consist  in  part of representa-
 tives  from the affected parties, to study
 the problem and recommend an appropri-
 ate solution.
   (iv) The procedure  and  schedule  for
 mediation of individual disputes shall be
 determined by the mediator in consulta-
 tion with the parties.
   (v) If formal public hearings are held in
 connection with the actions  taken  under
 this  paragraph, Agency requirements at
 40 CFR 25.5 shall be followed.
   (2) Arbitration.  Where  the  parties to
 the dispute agree to participate in the dis-
 pute resolution process, the Regional  Ad-
 ministrator may appoint an arbitrator or
 arbitration panel to arbitrate the dispute.
 Arbitrators and panel members shall be
 EPA  employees,  employees from  other
 Federal agencies, or  other individuals
 with appropriate qualifications. The  Re-
gional  administrator shall select  as arbi-
 trators and arbitration panel  members in-
dividuals who are agreeable to all parties,
are knowledgeable concerning  the re-
quirements of the water quality standards
program, have  a basic understanding of
the political  and  economic  interests of
 Tribes  and States involved, and  are  ex-
 pected  to fulfill the duties fairly and  im-
 partially.
   (i) The arbitrator or arbitration panel
 shall conduct one or more private or pub-
 lic meetings with the parties and actively
 solicit  information pertaining  to  the  ef-
 fects of differing water quality pcnnil re-
 quirements on upstream and downstream
 dischargers, comparative  risks  to  public
 health and the environment, economic  im-
 pacts, present and historical water uses,
 the  quality of the waters subject  to such
 standards, and other  factors relevant to
 the  dispute such as whether proposed wa-
 ter  quality  criteria are  more  stringent
 than necessary to support designated uses,
 more stringent than natural background
 water quality or whether designated uses
 are  reasonable given natural background
 water quality.
   (ii) Following consideration of relevant
 factors  as defined in paragraph (f)(2)(i)
 of this  section, the arbitrator or arbitra-
 tion panel shall have  the authority  and
 responsibility to provide  all parties  and
 the  Regional Administrator with  a writ-
 ten  recommendation for resolution of  the
 dispute. Arbitration panel recommenda-
 tions shall, in general,  be reached by ma-
 jority vote.  However,  where  the  parties
 agree to binding arbitration, or where re-
 quired  by the  Regional Administrator,
 recommendations of  such arbitration
 panels  may  be  unanimous decisions.
 Where  binding or non-binding arbitration
 panels cannot reach a  unanimous recom-
 mendation after a reasonable period  of
 time, the  Regional Administrator may di-
 rect the panel to issue  a non-binding deci-
 sion by majority vote.
   (iii) The arbitrator or arbitration panel
 members  may consult  with EPA's Office
 of General  Counsel on legal issues, but
 otherwise shall have no ex pane commu-
 nications pertaining to  the dispute. Feder-
 al employees who are  arbitrators or arbi-
 tration  panel members shall  be neutral
 and  shall not be predisposed for or against
 the position of any disputing party based
 on  any  Federal  Trust  responsibilities
 which their employers  may have with  re-
 spect to the Tribe. In addition, arbitrators
or arbitration panel  members  who  are
 Federal employees shall act independent-
 ly from  the normal hierarchy within their
agency.
  (iv) The parties arc not obligated  to
abide by  the arbitrator's or arbitration

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panel's recommendation  unless they vol-
untarily entered into a binding agreement
to do so.
  (v) If a party  to  the  dispute believes
that the arbitrator or arbitration  panel
has recommended an action contrary to or
inconsistent  with the Clean  Water Act,
the party may appeal the arbitrator's rec-
ommendation  to  the Regional Adminis-
trator. The request for appeal must be in
writing and  must include a description of
the statutory basis for altering the arbi-
trator's recommendation.
  (vi) The procedure and schedule for ar-
bitration of individual disputes shall  be
determined  by the arbitrator or arbitra-
tion panel in consultation with parties.
  (vii) If formal public hearings are held
in connection  with the actions taken  un-
der this paragraph. Agency requirements
at 40 CFR 25.5 shall be followed.
  (3) Dispute  Resolution Default  Proce-
dure. Where one or more parties (as de-
fined in paragraph (g) of this section) re-
fuse to participate in either the mediation
or arbitration  dispute resolution process-
es,  the  Regional  Administrator may  ap-
point a  single official or panel to  review
available  information  pertaining  to  the
dispute and  to issue a written recommen-
dation for resolving the  dispute. Review
officials shall be EPA employees, employ-
ees from other Federal agencies, or other
individuals  with  appropriate  qualifica-
tions. Review  panels shall include appro-
priate members to be selected by the  Re-
gional Administrator in consultation with
the  participating  parties.  Recommenda-
tions of such review officials  or  panels
shall, to the extent possible given the lack
of participation by one or more parties, be
reached in a manner identical to that for
arbitration  of  disputes  specified  in
paragraphs (f)(2)(i) through (f)(2)(vii) of
this section.
   (g) Definitions. For the purposes of this
section:
   (1)  Dispute  Resolution  Mechanism
means the  EPA mechanism  established
pursuant  to the  requirements of  Clean
Water Act  section  518(e)  for  resolving
unreasonable consequences that arise as a
result of differing water quality standards
that may be  set by States and  Indian
Tribes located  on common bodies  of  wa-
ter.
   (2) Parties to a State-Tribal dispute in-
clude the State and the Tribe and may, at
the discretion of the Regional Administra-
tor, include an NPDES permittee, citizen,
citizen group, or other affected entity.
[§131.7 added at 56 FR 64893, Dec. 12,
1991]

§131.8 Requirements for Indian Tribes to
  be treated  as States  for purposes of
  water quality standards.
  (a) The Regional Administrator, as de-
termined based on OMB Circular A105,
may treat an Indian Tribe as  a State for
purposes of the water quality standards
program if the  Tribe meets the following
criteria:
  (l)The Indian Tribe  is recognized by
the Secretary of the Interior and meets
the definitions in §131.3(k) and (1),
  (2) The Indian Tribe  has a governing
body carrying out substantial governmen-
tal  duties and powers,
  (3) The water quality standards  pro-
gram to be administered  by  the  Indian
Tribe pertains to the management  and
protection of water  resources which are
within the borders of the Indian reserva-
tion and held by the Indian Tribe, within
the borders of the Indian reservation and
held by the United States in trust for In-
dians, within the borders of  the  Indian
reservation and held by a member of the
Indian Tribe if such property interest  is
subject to a trust restriction on alienation,
or otherwise within the borders of the In-
dian reservation, and
  (4) The Indian Tribe is reasonably ex-
pected to be capable, in the Regional Ad-
ministrator's judgment, of carrying out
the functions of an effective water quality
standards program in a manner consistent
with the terms and  purposes  of the Act
and applicable  regulations.
  (b) Requests by Indian Tribes for treat-
ment as States for purposes of water  qual-
ity  standards should be  submitted to the
lead EPA  Regional  Administrator.  The
application shall include the following in-
formation:
  (1) A statement that the Tribe is recog-
nized by the  Secretary of the  Interior.
  (2) A  descriptive statement  demon-
strating that  the Tribal governing body is
currently carrying out substantial govern-
mental duties and powers over a defined
area. The statement shall:
  (i) Describe the form of the Tribal gov-
ernment;
  (ii) Describe the types of governmental
functions currently performed  by the
Tribal governing body such as,  but not
limited  to, the exercise of police powers
affecting (or relating to) the health, safe-
ty, and welfare of the affected population,
taxation, and the exercise of the power of
eminent domain; and
  (iii) Identify the source of the Tribal
government's  authority to carry out  the
governmental  functions currently being
performed.
  (3) A descriptive statement of the Indi-
an  Tribe's  authority  to  regulate water
quality. The statement shall include:
  (i) A  map or  legal  description of  the
area over which  the Indian Tribe asserts
authority  to regulate surface water quali-
ty;
  (ii) A statement by the  Tribe's  legal
counsel  (or  equivalent official) which  de-
scribes  the basis for the Tribes assertion
of authority;
  (iii) A  copy of all documents such as
Tribal constitutions, by-laws, charters, ex-
ecutive  orders, codes,  ordinances, and/or
resolutions which support the Tribe's as-
sertion of authority; and
  (iv) an  identification of the surface wa-
ter for which the Tribe proposes  to estab-
lish water quality standards.
  (4) A narrative statement describing
the capability  of the Indian  Tribe to
administer an  effective water quality stan-
dards program. The narrative statement
shall include:
  (i) A  description of the Indian Tribe's
previous management experience includ-
ing, but not limited to, the administration
of programs and services authorized by
the Indian  Self-Determination and Edu-
cation Assistance Act (25 U.S.C. 450 et
seq.), the Indian Mineral  Development
Act (25 U.S.C. 2101 et seq.), or  the Indi-
an Sanitation  Facility Construction Activ-
ity  Act  (42  U.S.C. 2004a);
  (ii) A list of existing environmental or
public health  programs administered by
the Tribal governing body  and copies of
related  Tribal laws, policies, and regula-
tions;
   (iii) A description of the entity (or enti-
ties) which exercise the executive, legisla-
tive, and  judicial functions of the Tribal
government;
  (iv) A description of the existing or pro-
posed, agency of the Indian Tribe which
will assume primary responsibility for es-
tablishing, reviewing,  implementing and
revising water quality standards;
   (v) A description of the  technical and
administrative capabilities of the staff to

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administer and manage an effective water
quality standards  program or  a plan
which proposes how the Tribe will acquire
additional administrative and  technical
expertise. The plan  must address how the
Tribe will obtain the funds to acquire the
administrative and technical expertise.
  (5) Additional documentation required
by the Regional Administrator which, in
the judgment of the Regional Administra-
tor, is necessary to support a Tribal re-
quest for treatment as a  State.
  (6) Where the  Tribe has  previously
qualified for treatment as a State under a
Clean Water Act or Safe Drinking Water
Act program, the Tribe need only provide
the required information which  has  not
been submitted in a previous treatment as
a State application.
  (c) Procedure for processing  an Indian
Tribe's application  for  treatment as a
State.
  (l)The Regional Administrator shall
process an application of an Indian Tribe
for treatment as a State submitted pursu-
ant to 131.8(b) in  a  timely manner. He
shall promptly notify  the Indian Tribe of
receipt of the application.
  (2) Within 30 days after receipt of the
Indian Tribe's  application  for  treatment
as a State,  the Regional Administrator
shall  provide appropriate notice.  Notice
shall:
  (i) Include  information  on the  sub-
stance and basis of the Tribe's assertion of
authority to regulate the quality of reser-
vation waters; and
  (ii) Be provided  to all  appropriate gov-
ernmental entities.
  (3) The Regional Administrator shall
provide 30 days for comments to be sub-
mitted on the  Tribal application. Com-
ments shall be limited to the Tribe's asser-
tion of authority.
  (4) If  a Tribe's  asserted authority is
subject  to  a  competing or conflicting
claim,  the Regional Administrator, after
consultation with the Secretary of the In-
terior, or his designee,  and in consider-
ation  of other  comments received, shall
determine whether the  Tribe has  ade-
quately demonstrated that  it meets  the
requirements of 131.8(a)(3).
  (5) Where the Regional Administrator
determines  that a  Tribe meets  the re-
quirements  of  this  section,  he  shall
promptly  provide written notification  to
the Indian Tribe that the Tribe has quali-
fied to be treated as a State for purposes
of water quality standards and that  the
Tribe may initiate the formulation and
adoption of water quality  standards  ap-
provable under this part.
[§131.8 added at 56 FR 64893, Dec. 12,
1991]

Subpart B—Establishment of Water
         Quality Standards

§131.10 Designation of uses.
  (a) Each State must specify appropri-
ate water uses to be achieved and protect-
ed. The classification of the waters of the
State must take into consideration the use
and value of water for public water sup-
plies, protection and propagation of fish,
shellfish and wildlife, recreation in and on
the water, agricultural, industrial, and
other purposes including navigation. In no
case shall a State adopt waste transport or
waste assimilation  as a designated use for
any waters of the United States.
  (b) In designating uses of a water body
and the appropriate  criteria  for  those
uses,  the State shall  take  into consider-
ation the water quality standards of down-
stream  waters  and shall ensure  that its
water quality standards provide for  the
attainment and maintenance  of the  water
quality standards of downstream  waters.
  (c) States may adopt sub-categories of
a use and set the  appropriate  criteria to
reflect varying needs  of such sub-catego-
ries of uses, for instance, to  differentiate
between cold water and warm water fish-
eries.
  (d) At a minimum,  uses are deemed at-
tainable  if they can be achieved by  the
imposition of effluent limits required  un-
der sections 301 (b) and 306 of  the Act
and cost-effective  and reasonable best
management  practices   for  nonpoint
source control.
  (e) Prior to  adding or  removing any
use, or establishing sub-categories of  a
use, the State shall provide notice and an
opportunity for  a public hearing  under
§131.20(b) of this regulation.
  (0 States may adopt seasonal uses as
an  alternative  to  reclassifying a  water
body or segment thereof to uses requiring
less stringent water  quality criteria.  If
seasonal  uses are adopted, water quality
criteria  should  be  adjusted to reflect  the
seasonal  uses, however, such criteria shall
not preclude  the attainment  and  mainte-
nance of a more protective  use in another
season.
  (g) States may remove a designated use
which is not an existing use, as defined in
§131.3, or establish sub-categories of a
use if the State can demonstrate that at-
taining the designated use is not feasible
because:
  (1) Naturally occurring pollutant con-
centrations prevent the attainment of the
use; or
  (2) Natural, ephemeral, intermittent or
low flow conditions or water levels prevent
the attainment  of  the use, unless these
conditions may be compensated for by the
discharge of sufficient volume of effluent
discharges without  violating  State  water
conservation requirements to enable uses
to be met; or
  (3) Human   caused  conditions  or
sources of pollution  prevent  the  attain-
ment of the use and cannot be remedied
or would cause more environmental dam-
age to  correct than to leave in place; or
  (4) Dams, diversions or other types of
hydrologic modifications preclude the at-
tainment of the use, and it is not feasible
to restore  the water  body  to  its original
condition  or to operate such modification
in a way  that would result in the attain-
ment of the use; or
  (5) Physical  conditions related to  the
natural features of the water body, such
as the  lack of  a proper substrate, cover,
flow, depth, pools, riffles, and the like, un-
related to water quality, preclude attain-
ment of aquatic life protection uses; or
  (6) Controls  more stringent than those
required by sections  301(b) and  306 of
the Act  would  result  in substantial and
widespread economic and social  impact.
  (h) States may not  remove designated
uses if:
  (1) They are existing uses, as defined in
§131.3, unless a use requiring more strin-
gent criteria is  added; or
  (2) Such uses will be attained by imple-
menting effluent limits required under
sections 301 (b) and 306 of the Act and by
implementing cost-effective and reason-
able best  management practices  for
nonpoint source control.
  (i) Where existing  water  quality stan-
dards specify  designated uses less than
those which are presently being  attained,
the State  shall  revise its standards to re-
flect the uses actually being attained.
  (j) A State must conduct a use attaina-
bility analysis as described  in §!31.3(g)
whenever:

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  (l)The State designates or has desig-
nated uses that do not include  the  uses
specified in section  101(a)(2) of the  Act,
or
  (2) The State wishes to remove a desig-
nated  use that is specified  in section
101(a)(2) of the Act or to adopt subcate-
gories  of  uses  specified  in   section
101(a)(2) of the Act  which  require less
stringent criteria.
  (k) A State is not required to conduct a
use attainability analysis under this regu-
lation  whenever designating uses which
include  those  specified  in   section
 I01(a)(2) of the Act.

§131.11 Criteria.
  (a) Inclusion of pollutants:
  (1) States must adopt those water qual-
ity  criteria that protect  the designated
use. Such criteria must be based on sound
scientific rationale and must contain  suffi-
cient parameters or constituents to pro-
tect the designated use. For waters with
multiple  use  designations,  the criteria
shall support the most sensitive  use.
   (2) Toxic pollutants.  States  must  re-
 view water quality data and information
 on  discharges  to  identify specific  water
 bodies where toxic pollutants may be  ad-
 versely alfccting water quality or the at-
 tainment of the designated water use or
 where the levels of toxic pollutants are at
 a level to warrant concern and must adopt
 criteria  for such toxic pollutants applica-
 ble to the water body  sufficient  to protect
 the designated use. Where a State adopts
 narrative  criteria for  toxic pollutants to
 protect  designated uses,  the State  must
 provide information identifying  the meth-
 od by which the State intends to regulate
 point source discharges of toxic  pollutants
 on water quality  limited segments based
 on such narrative criteria. Such informa-
 tion may be included  as part of the stan-
 dards or may  be included in documents
 generated by the  State in response to the
 Water  Quality  Planning and  Manage-
 ment Regulations (40 CFR part 35).
    (b) Form of criteria: In establishing cri-
 teria, States should:
    (1) Establish  numerical values based
 on:
    (i) 304(a) Guidance; or
    (ii) 304(a) Guidance modified to reflect
 site-specific conditions; or
    (iii) Other  scientifically defensible
  methods;
    (2) Establish narrative criteria or crite-
  ria based upon  biomonitoring methods
where numerical criteria cannot be estab-
lished or to supplement numerical  crite-
ria.

§131.12 Antidegradation policy.

  (a) The State shall develop and adopt a
statewide  antidegradation  policy  and
identify  the  methods  for  implementing
such policy pursuant to this subpart. The
antidegradation policy  and implementa-
tion methods shall, at a  minimum, be con-
sistent with the following-
  (1) Existing  instream water uses and
the level of water quality necessary to pro-
tect the existing uses shall be maintained
and protected.
  (2) Where the  quality of the waters ex-
ceed levels necessary to support propaga-
tion of fish, shellfish, and wildlife and rec-
reation in and  on the water, that quality
shall be maintained and protected unless
the  State finds, after  full satisfaction of
the  intergovernmental  coordination and
public  participation  provisions of  the
State's continuing planning process, that
allowing lower water quality is necessary
to  accommodate important  economic or
social  development in  the area in  which
the  waters arc located. In allowing such
degradation  or lower  water quality, the
State shall assure water quality adequate
to protect existing uses fully. Further, the
State  shall  assure  that  there  shall  be
achieved the highest statutory and regula-
tory requirements for all new and existing
 point  sources  and all  cost-effective  and
 reasonable best management practices for
 nonpoint source control.
   (3)  Where high quality waters consti-
 tute an outstanding  National  resource,
 such as  waters  of National  and State
 parks and wildlife refuges and waters of
 exceptional recreational or ecological sig-
 nificance, that  water quality  shall  be
 maintained and  protected.
   (4) In those cases where  potential wa-
 ter quality impairment associated  with a
 thermal  discharge is  involved, the  an-
 tidegradation  policy  and  implementing
 method shall  be consistent with section
 316 of the Act.

 §131.13 General policies.

    States may, at their discretion, include
 in their State standards, policies generally
 affecting their application and implemen-
 tation,  such as  mixing zones,  low flows
 and variances. Such policies are subject to
 EPA  review and approval.
 Subpart C—Procedures for Review
   and Revision of Water  Quality
              Standards

§131.20 State review and revision of water
 quality standards.
  (a) State review. The  State shall  from
time to time, but at least once every three
years,  hold  public  hearings  for the pur-
pose of reviewing applicable water quality
standards and, as appropriate,  modifying
and  adopting standards. Any water body
segment with water quality standards that
do not include the uses specified in section
101(a)(2) of the Act shall be re-examined
every three years to determine  if any new
information has become available. If such
new information indicates that  the uses
specified in  section 101(a)(2) of the Act
are  attainable, the State shall revise its
standards accordingly.  Procedures  States
establish for identifying and  reviewing
water  bodies for review should be incorpo-
rated into their Continuing Planning Pro-
cess.
   (b)  Public participation. The   State
shall hold a public hearing for the purpose
of reviewing water quality standards, in
accordance  with provisions of  State law,
 EPA's water quality management regula-
tion (40 CFR I30.3(b)(6)) and  public
 participation regulation (40  CFR  part
 25). The proposed water quality stan-
dards revision  and supporting  analyses
shall be made available to the public prior
 to the hearing.
   (c) Submittat to EPA. The  State shall
 submit the  results of the review, any sup-
 porting analysis for the use attainability
 analysis, the methodologies  used for site-
 specific criteria development, any general
 policies applicable to water quality stan-
 dards and any revisions of the standards
 to the Regional  Administrator for review
 and approval, within 30 days  of the final
 State action to adopt  and certify  the re-
 vised  standard, or if no revisions  are made
 as a result of the review, within 30  days of
 the completion of the review.

 §131.21 EPA review and approval of water
   quality standards.
   (a) After the State submits  its officially
 adopted revisions, the  Regional  Adminis-
 trator shall either:
   (1) Notify  the State within 60 days
 that the revisions are approved, or
   (2) Notify  the State within 90 days
 that the revisions are disapproved. Such

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notification  of disapproval  shall specify
the changes needed to assure compliance
with the requirements of the Act and this
regulation,  and shall explain  why  the
State standard is not in  compliance with
such  requirements. Any  new or revised
State standard must be  accompanied by
some type of supporting  analysis.
  (b) The  Regional Administrator's ap-
proval or disapproval of a State  water
quality standard shall be based on the re-
quirements  of the Act  as  described in
§§131.5, and  131.6.
  (c) A State water quality standard re-
mains in effect, even though disapproved
by EPA, until the  State revises it or EPA
promulgates a rule that supersedes the
State water quality standard.
  (d) EPA  shall, at least annually, pub-
lish in the FEDERAL REGISTER a notice of
approvals under this section.

§131.22 EPA promulgation  of  water
  quality standards.
  (a) If the  Stale does not adopt  the
changes specified by the Regional Admin-
istrator within 90  days after notification
of the  Regional  Administrator's  disap-
proval,  the  Administrator shall  promptly
propose and promulgate  such standard.
  (b) The  Administrator may  also  pro-
pose and promulgate a regulation, appli-
cable to one or more States, setting forth
a new or revised standard upon determin-
ing such a standard is necessary to meet
the requirements of the Act.
  (c) In promulgating water quality stan-
dards, the Administrator is  subject to the
same policies, procedures,  analyses,  and
public participation requirements  estab-
lished for States in these regulations.

 Subpart D—Federally Promulgated
      Water  Quality Standards

§131.31 Arizona.
  (a) Article 6, Part 2 is amended  as fol-
lows:
  (l)Reg. 6-2-6.11 shall read:
  Reg. 6-2-6.11 Nutrient Standards  A.  The
mean annual  total phosphate and mean  annual
total nitrate concentrations of the  following waters
shall  not  exceed  the values given below nor  shall
the total phosphate or total nitrate concentrations
of more than 10 percent of the samples in any year
exceed the 90 percent values  given below. Unless
otherwise specified, indicated  values also apply to
tributaries to the named waters.

1 Colorado River from Utah
border to Willow Beach
(main stem) 	
2 Colorado River from Wil-
low Beach to Parker Dam
(mam stem) 	
3 Colorado River from Par-
ker Dam to Imperial Dam
(main stem) . .
4 Colorado River from Im-
perial Dam to Moretos
Dam (main stem)
5 Gila River from New Mex-
ico border to San Carlos
Reservoir (excluding San
Carlos Reservoir) 	
6 Gila River from San Car-
los Reservoir to Ashurst
Hayden Dam (including
San Carlos Reservoir).
7 San Pedro River
8 Verde River (except Gran-
ite Creek)
9 Salt River above Roose-
velt Lake
10 Santa Cruz River from
international boundary
near Nogales to Sanuanta
11 Little Colorado River
above Lyman Reservoir
Mean 90 pet annual value
Total
phosphates
as PCumg/l


0 04-0 06


006-010


008-012


0.10-0.10



0 50-0 80



0 30-0 50
0 30-0 50

0 20-0 30

0 20-0 30


0 50-0 80

0 30-0 50
Total ni-
trates as
NOimg/l


4-7


5


5-7


5-7


















  B The above standards are intended to protect
the beneficial uses of the named waters. Because
regulation of nitrates and phosphates alone may
not be adequate to protect waters from eutrophica-
tion, no substance shall be added to any surface
water which produces aquatic growth to the extent
that such growths create a public nuisance or in-
terference with beneficial uses of the water defined
and designated in Reg 6-2-6 5
  (2) Reg. 6-2-6.10 Subparts A and B are
amended to include Reg.  6-2-6.11 in  se-
ries with Regs. 6-2-6.6, 6-2-6.7 and 6-2-
6.8.

§131.33  [Reserved]

§131.34  [Reserved]

§131.35Colville  Confederated  Tribes
  Indian Reservation.
  The water quality standards applicable
to the waters within the Colville  Indian
Reservation,  located  in  the State  of
Washington.
  (a) Background.
  (1) It is  the purpose of these Federal
water quality standards to prescribe mini-
mum  water quality  requirements for the
surface waters located within the exterior
boundaries of the Colville Indian Reserva-
tion  to ensure compliance with  section
303(c) of the Clean Water Act.
  (2) The  Colville Confederated Tribes
have a primary interest in the protection,
control, conservation,  and utilization of
the water resources of the Colville Indian
Reservation.  Water  quality  standards
have been enacted into tribal law by the
Colville Business Council of the Confed-
erated Tribes of the Colville  Reservation,
as the Colville Water Quality Standards
Act, CTC Title 33 (Resolution No. 1984-
526 (August 6, 1984) as amended by Res-
olution No. 1985-20 (January 18, 1985)).
  (b) Territory  Covered. The provisions
of these water quality standards shall ap-
ply to all surface waters within the exteri-
or boundaries of the Colville Indian Res-
ervation.
  (c) Applicability, Administration  and
Amendment.
  (l)The water quality  standards in this
section shall be used by the Regional Ad-
ministrator for establishing any  water
quality based  National Pollutant Dis-
charge  Elimination  System  Permit
(NPDES)  for point sources on  the Col-
ville Confederated Tribes Reservation.
  (2) In conjunction with the issuance of
section 402 or section 404  permits, the
Regional  Administrator may designate
mixing zones in the waters of the United
States on  the  reservation on  a  case-by-
case basis. The size of such mixing zones
and the in-zone water quality in such mix-
ing zones shall be consistent with the ap-
plicable procedures  and guidelines in
EPA's Water Quality Standards Hand-
book  and  the  Technical Support  Docu-
ment  for  Water  Quality Based Toxics
Control.
  (3) Amendments to the section at the
request of the Tribe shall proceed in the
following manner.
  (i) The requested amendment shall first
be  duly  approved by the Confederated
Tribes of the Colville Reservation (and so
certified by the  Tribes   Legal  Counsel)
and submitted  to  the  Regional Adminis-
trator.
  (ii) The requested amendment shall be
reviewed  by EPA  (and  by the State of
Washington, if the action would affect a
boundary water).
  (iii) If deemed in compliance with the
Clean  Water Act, EPA  will  propose and
promulgate an appropriate change to this
section.

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  (4) Amendment of  this  section  at
EPA's initiative will follow consultation
with the Tribe and other appropriate enti-
ties. Such amendments will  then  follow
normal EPA rulemaking procedures.
  (5) All other applicable provisions of
this part 131 shall apply on  the Colville
Confederated Tribes Reservation. Special
attention  should  be  paid  to  §§131.6,
131.10,131.11 and 131.20 for any amend-
ment  to these standards to be initiated by
the Tribe.
  (6) All numeric criteria contained in
this section  apply at all  in-stream flow
rates  greater than or  equal  to  the flow
rate calculated as the minimum 7-consec-
utive  day average flow with a recurrence
frequency of once in ten years (7Q10);
narrative criteria  ( §131.35(e)(3)) apply
regardless of  flow. The 7Q10  low flow
shall be calculated using methods recom-
mended by the U.S. Geological Survey.
  (d) Definitions.
  (1) "Acute toxicity" means a deleteri-
ous response (e.g.,  mortality, disorienta-
tion,  immobilization) to a  stimulus ob-
served in 96 hours or less.
  (2) "Background  conditions" means
the biological, chemical, and physical con-
ditions of a water body, upstream from
the point  or non-point  source  discharge
under consideration.  Background  sam-
pling  location in  an enforcement  action
will be upstream from  the point of dis-
charge, but  not upstream from other in-
flows. If several discharges to any water
body  exist, and an enforcement  action is
being taken for possible violations to the
standards, background sampling will be
undertaken  immediately upstream from
each discharge.
  (3) "Ceremonial  and Religious water
use" means activities involving traditional
Native American spiritual practices
which involve, among other things, prima-
ry (direct) contact with water.
  (4) "Chronic Toxicity" means the low-
est concentration of a constituent causing
observable effects (i.e., considering lethal-
ity, growth, reduced  reproduction, etc.)
over a relatively long period of time, usu-
ally a 28-day test period for small fish test
species.
  (5) "Council"  or  "Tribal  Council"
means the Colviile Business Council of
the Colville Confederated Tribes.
  (6) "Geometric mean"  means  the
"nth" root of a product of "n" factors.
  (7) "Mean retention time" means the
time obtained by  dividing a  reservoir's
mean annual minimum total storage by
the non-zero 30-day,  ten-year  low-flow
from the reservoir.
  (8) "Mixing Zone" or "dilution zone"
means  a  limited  area or volume  of water
where initial dilution of a discharge takes
place; and  where numeric  water quality
criteria can be exceeded but acutely toxic
conditions are prevented from occurring.
  (9) "pH" means the negative logarithm
of the hydrogen  ion concentration.
  (10) "Primary  contact  recreation"
means  activities where a  person  would
have direct contact with  water to the
point of complete submergence, including
but not limited to skin  diving, swimming,
and water skiing.
  (11) "Regional Administrator" means
the Administrator of EPA's Region X.
  (12) "Reservation"  means  all  land
within  the  limits of the Colville Indian
Reservation, established on July 2, 1872
by Executive Order, presently containing
1,389,000 acres  more or less,  and under
the jurisdiction of the United States gov-
ernment, notwithstanding the issuance of
any  patent, and including rights-of-way
running through  the reservation.
  (13) "Secondary contact recreation"
means  activities  where a  person's water
contact would be  limited  to the  extent
that bacterial infections of eyes, ears, res-
piratory, or digestive systems or urogeni-
tal areas would normally be avoided (such
as wading or fishing).
  (14) "Surface  water" means all water
above the surface of the ground within the
exterior boundaries of the Colville Indian
Reservation including  but  not limited to
lakes,  ponds, reservoirs,  artificial im-
poundments,  streams, rivers,  springs,
seeps and wetlands.
  (15) "Temperature"  means water tem-
perature expressed in Centigrade degrees
(C).
  (16) "Total dissolved solids" (TDS)
means  the total filterable residue  that
passes through a  standard glass fiber filter
disk and remains  after evaporation and
drying  to a constant weight at 180 degrees
C. it is considered to be a measure of the
dissolved salt content of the water.
  (17) "Toxicity"  means  acute and/or
chronic toxicity.
  (18) "Tribe"  or  "Tribes"  means  the
Colville Confederated Tribes.
  (19) "Turbidity" means  the  clarity  of
water expressed as nephelometric turbidi-
ty units (NTU) and measured with a cali-
brated turbidimeter.
  (20) "Wildlife habitat" means the wa-
ters  and surrounding land  areas of the
Reservation used  by fish,  other aquatic
life and wildlife at any stage of their life
history or activity.
  (e) General considerations. The follow-
ing general  guidelines shall apply to the
water quality standards and classifications
set forth in the use designation Sections.
  (1) Classification  Boundaries. At the
boundary between  waters of  different
classifications,  the  water  quality stan-
dards for the higher classification  shall
prevail.
  (2) Antidegradation Policy.  This an-
tidegradation policy shall be applicable to
all surface waters of the  Reservation.
  (i) Existing in-stream  water  uses and
the level of water quality necessary to pro-
tect the existing uses shall be maintained
and protected.
  (ii) Where the quality of the waters ex-
ceeds levels necessary to support propaga-
tion of fish, shellfish, and wildlife and rec-
reation  in and on the water, that quality
shall be maintained  and  protected unless
the Regional  Administrator finds, after
full satisfaction of the inter-governmental
coordination and public participation pro-
visions of the Tribes' continuing planning
process, that allowing lower water quality
is necessary  to accommodate  important
economic or social  development in the
area in which the waters are located.  In
allowing such degradation or lower water
quality, the  Regional Administrator shall
assure water quality adequate  to protect
existing uses fully. Further, the Regional
Administrator shall assure that  there
shall  be achieved the highest  statutory
and  regulatory requirements for all new
and  existing point sources  and all  cost-
effective  and reasonable  best  manage-
ment practices for nonpoint source con-
trol.
  (iii) Where high  quality waters are
identified as constituting an outstanding
national or reservation resource, such  as
waters within areas designated as unique
water quality management areas and wa-
ters otherwise of exceptional recreational
or ecological significance, and  are  desig-
nated as special resource waters, that wa-
ter  quality shall be  maintained and pro-
tected.

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  (iv) In those cases where potential wa-
ter  quality impairment associated  with a
thermal  discharge  is involved, this  an-
tidegradation policy's  implementing
method shall  be  consistent  with section
316 of the Clean  Water Act.
  (3) Aesthetic  Qualities.  All waters
within the Reservation,  including those
within mixing zones, shall be  free from
substances, attributable  to  wastewater
discharges or  other pollutant sources,
that:
  (i) Settle to form objectionable depos-
its;
  (ii) Float as debris, scum, oil, or other
matter forming nuisances;
  (iii) Produce objectionable color, odor,
taste, or turbidity;
  (iv) Cause  injury to, are toxic to,  or
produce  adverse  physiological  responses
in humans, animals, or plants; or
  (v) Produce  undesirable  or  nuisance
aquatic life.
  (4) Analytical  Methods.
  (i) The analytical testing methods used
to measure or otherwise evaluate compli-
ance with water quality standards shall to
the extent practicable, be in accordance
with the  "Guidelines  Establishing Test
Procedures for the Analysis of Pollutants"
(40 CFR part 136). When a testing meth-
od  is  not available for a  particular sub-
stance, the most  recent  edition of "Stan-
dard  Methods for  the Examination  of
Water and Wastewater" (published by
the American Public Health Association,
American Water  Works Association, and
the Water Pollution Control  Federation)
and other or  superseding methods pub-
lished and/or approved  by EPA shall be
used.
  (0 General Water Use and Criteria
Classes. The following criteria shall apply
to the various classes of surface waters on
the Colville Indian  Reservation:
  (1) Class 1 (Extraordinary)—
  (i) Designated  uses.  The designated
uses include,  but  are not  limited to,  the
following:
  (A) Water supply (domestic, industrial,
agricultural).
  (B) Stock watering.
  (C) Fish and shellfish: Salmonid  migra-
tion, rearing,  spawning,  and harvesting;
other  fish  migration, rearing, spawning,
and harvesting.
  (D) Wildlife habitat.
  (E) Ceremonial  and  religious  water
use.
  (F) Recreation (primary contact recre-
ation, sport fishing, boating and aesthetic
enjoyment).
  (G) Commerce and navigation.
  (ii) Water quality criteria.
  (A) Bacteriological Criteria—The geo-
metric mean of the enterococci bacteria
densities in samples taken over a 30 day
period  shall not exceed 8 per 100 millili-
ters, nor shall any single sample exceed an
enterococci density of 35 per 100 millili-
ters. These limits are calculated  as  the
geometric  mean of the collected samples
approximately equally spaced over a thir-
ty day period.
  (B) Dissolved oxygen—The  dissolved
oxygen  shall exceed 9.5 mg/1.
  (C) Total                 dissolved
gas—concentrations shall not exceed  110
percent of the  saturation value for gases
at the existing atmospheric and hydrostat-
ic pressures at any point of sample collec-
tion.
  (D) Temperature—shall  not exceed
16.0 degrees C due to human activities.
Temperature increases shall not, at any
time, exceed t=23/(T-t-5).
  (/) When natural conditions exceed
16.0 degrees C, no temperature increase
will be allowed  which will raise  the receiv-
ing water by greater than 0.3 degrees  C.
  (2) For purposes  hereof, "t"  represents
the permissive temperature change across
the dilution zone; and "T" represents the
highest  existing temperature  in this water
classification outside of any dilution zone.
  (3) Provided  that temperature increase
resulting from  nonpoint source activities
shall not exceed  2.8 degrees C, and  the
maximum water temperature shall not ex-
ceed 10.3 degrees C.
  (E) pH shall be within the range of 6.5
to 8.5 with a human-caused variation of
less than 0.2 units.
  (F) Turbidity shall not exceed 5 NTU
over background turbidity when the back-
ground  turbidity is  50 NTU or less,  or
have more than a 10 percent increase in
turbidity when the  background turbidity
is more than 50 NTU.
  (G) Toxic, radioactive, nonconvention-
al, or deleterious material concentrations
shall be less than those  of public health
significance, or  which may cause acute or
chronic  toxic conditions to the aquatic  bi-
ota, or which may adversely  affect desig-
nated water uses.
  (2) Class II (Excellent).—
  (i) Designated uses. The  designated
uses include but are not  limited  to, the
following:
  (A) Water supply (domestic, industrial,
agricultural).
  (B) Stock watering.
  (C) Fish and shellfish: Salmonid migra-
tion, rearing,  spawning, and  harvesting;
other fish  migration, rearing, spawning,
and harvesting; crayfish rearing,  spawn-
ing, and harvesting.
  (D) Wildlife habitat.
  (E) Ceremonial  and  religious  water
use.
  (F) Recreation (primary contact recre-
ation, sport fishing, boating and aesthetic
enjoyment).
  (G) Commerce and navigation.
  (ii) Water quality criteria.
  (A) Bacteriological Criteria—The geo-
metric mean of the enterococci bacteria
densities in samples taken over a  30 day
period shall not exceed 16/100 ml, nor
shall any single sample  exceed an  entero-
cocci density  of 75  per  100  milliliters.
These limits are calculated as the geomet-
ric  mean of the collected samples approxi-
mately  equally spaced over a  thirty day
period.
  (B) Dissolved oxygen—The  dissolved
oxygen  shall exceed 8.0 mg/1.
  (C) Total  dissolved  gas—concentra-
tions shall  not  exceed 110 percent of the
saturation  value for gases at the existing
atmospheric and hydrostatic pressures at
any point of sample collection.
  (D) Temperature—shall  not  exceed
18.0 degrees C due to  human activities.
Temperature increases  shall not,  at any
time, exceed t=28/(T+7).
  (/) When natural conditions exceed 18
degrees C no temperature increase will be
allowed which will raise the receiving wa-
ter  temperature by  greater than  0.3 de-
grees C.
  (2) For purposes  hereof, "t" represents
the permissive temperature change across
the dilution zone; and "T" represents the
highest existing temperature in this water
classification outside of any dilution zone.
  (J) Provided  that temperature increase
resulting from  non-point source activities
shall not exceed 2.8  degrees C, and the
maximum water temperature shall  not ex-
ceed 18.3 degrees C.
  (E) pH shall  be within the range of 6.5
to 8.5 with a human-caused variation of
less than 0.5 units.

-------
  (F) Turbidity shall not exceed 5 NTU
over background turbidity when the back-
ground  turbidity is  50 NTU or less, or
have more than a 10 percent increase in
turbidity when the background turbidity
is more than 50 NTU.
  (G) Toxic, radioactive, nonconvention-
al, or deleterious material concentrations
shall be less than those of public health
significance, or which may cause acute or
chronic toxic conditions to the aquatic bi-
ota, or  which may adversely affect desig-
nated water uses.
  (3) Class HI (Good).—
  (i) Designated  uses.  The designated
uses include but are not limited to, the
following:
  (A) Water supply (industrial, agricul-
tural).
  (B) Stock watering.
  (C) Fish and shellfish: Salmonid migra-
tion, rearing, spawning,  and harvesting;
other fish  migration,  rearing, spawning,
and  harvesting; crayfish  rearing, spawn-
ing,  and harvesting.
  (D) Wildlife habitat.
  (E) Recreation (secondary contact rec-
reation, sport fishing, boating and aesthet-
ic enjoyment).
  (F) Commerce and navigation.
  (ii) Water quality criteria.
  (A) Bacteriological Criteria—The geo-
metric  mean of the enterococci bacteria
densities in samples taken over a 30 day
period  shall not exceed  33/100 ml, nor
shall any single sample exceed an entero-
cocci density of 150 per  100 milliliters.
These limits are calculated as the geomet-
ric mean of the collected samples approxi-
mately  equally  spaced over a thirty day
period.
  (B) Dissolved oxygen.

7 day mean
1 day minimum* 	
Early life
stages1,*
9 5 (6.5)
8.0 (5.0)
Other life
stages
•NA
6.5
  ' These are water column concentrations recommended
 to achieve the required intergravel dissolved oxygen con-
 centrations shown in parentheses. The 3 mg/L differential
 is discussed in the dissolved oxygen criteria document
 (EPA 440/5-86-003, April 1986). For species that have ear-
 ly life stages exposed directly to the water column, the
 figures in parentheses apply
  * Includes all embryonic and larval stages and all juve-
 nile forms to 30-days following hatching
  * NA (not applicable)
  4 Alt  minima should be considered as instantaneous
 concentrations to be achieved at all times
   (C) Total  dissolved gas concentrations
 shall not exceed 110 percent of the satura-
tion value for gases at the existing atmo-
spheric and hydrostatic  pressures at any
point of sample collection.
  (D) Temperature shall not exceed 21.0
degrees C due to human activities. Tem-
perature increases shall  not, at any time,
exceed  t=34/(T+9).
  (/) When  natural conditions  exceed
21.0 degrees C  no temperature  increase
will be allowed which will raise the receiv-
ing water temperature by greater than 0.3
degrees C.
  (2) For purposes hereof, "t" represents
the permissive temperature change across
the dilution zone; and "T" represents the
highest existing temperature in this water
classification outside of any dilution  zone.
  (3) Provided that temperature increase
resulting from nonpoint source activities
shall not exceed  2.8  degrees  C, and  the
maximum water temperature shall not ex-
ceed 21.3 degrees C.
  (E) pH shall be within the range of 6.5
to 8.5  with a human-caused variation of
less than 0.5 units.
  (F) Turbidity shall not exceed  10 NTU
over background turbidity when the back-
ground turbidity is  50  NTU or  less, or
have more than a 20 percent increase in
turbidity when the background turbidity
is more than 50 NTU.
  (G)  Toxic, radioactive,  nonconvention-
al, or deleterious material concentrations
shall be less than those of public health
significance, or which may cause acute or
chronic toxic conditions  to the aquatic bi-
ota, or which may adversely affect desig-
nated water uses.
  (4) Class IV (Fair)—
  (i) Designated  uses.  The  designated
uses include but are not limited to, the
following:
  (A)  Water supply (industrial).
  (B) Stock watering.
  (C)  Fish (salmonid and  other  fish  mi-
gration).
  (D)  Recreation  (secondary  contact  rec-
reation, sport fishing, boating and aesthet-
ic enjoyment).
  (E) Commerce and navigation.
  (ii)  Water quality criteria.
  (A) Dissolved oxygen.





During
periods of
salmonid and
other fish
migration
4.0

During all
other time
periods

30




30 day mean .
7 day mean
7 day mean minimum .
During
periods of
salmonid and
other fish
migration
6.5
'NA
50
During all
other time
periods

5.5
'NA
40
 1 NA (not applicable).
 'All minima should be considered as instantaneous
concentrations to be achieved at all times.
  (B) Total  dissolved  gas—concentra-
tions shall not  exceed 110 percent of the
saturation value for gases at  the existing
atmospheric and hydrostatic  pressures at
any point of sample collection.
  (C) Temperature shall not  exceed 22.0
degrees C due to  human activities. Tem-
perature increases shall  not, at any time,
exceed t=20/(T+2).
  (/) When  natural  conditions  exceed
22.0 degrees C, no temperature increase
will be allowed which will raise the receiv-
ing water temperature by greater than 0.3
degrees C.
  (2) For purposes hereof, "t" represents
the permissive  temperature change across
the dilution zone; and "T" represents the
highest existing temperature in this water
classification outside of any dilution zone.
  (D) pH shall be within the  range of 6.5
to 9.0  with a human-caused  variation of
less than  0.5 units.
  (E) Turbidity shall not exceed 10 NTU
over background turbidity when the back-
ground turbidity  is 50  NTU or  less, or
have more than a 20 percent increase in
turbidity  when the background turbidity
is more than 50 NTU.
  (F) Toxic, radioactive,  nonconvention-
al, or deleterious  material concentrations
shall be less than those of public health
significance, or which may cause acute or
chronic toxic conditions  to the aquatic bi-
ota, or which may adversely  affect desig-
nated water uses.
  (5) Lake Class—
  (i) Designated  uses.  The  designated
uses include but  are not limited  to, the
following:
  (A)  Water supply (domestic, industrial,
agricultural).
  (B) Stock watering.
  (C)  Fish and shellfish: Salmonid migra-
tion, rearing,  spawning, and harvesting;
other fish migration, rearing,  spawning,
and harvesting; crayfish rearing,  spawn-
ing, and harvesting.
  (D) Wildlife habitat.
  (E) Ceremonial  and  religious  water
use.

-------
  (F) Recreation (primary contact recre-
ation, sport fishing, boating and aesthetic
enjoyment).
  (G) Commerce and navigation.
  (ii) Water quality criteria.
  (A) Bacteriological  Criteria.  The  geo-
metric  mean of the enterococci bacteria
densities  in samples taken over a 30 day
period  shall not  exceed  33/100 ml,  nor
shall any single sample exceed an entero-
cocci density of  150  per 100 milliliters.
These limits are calculated as the geomet-
ric mean  of the collected samples approxi-
mately  equally spaced over  a thirty day
period.
  (B) Dissolved oxygen—no  measurable
decrease  from natural conditions.
  (C) Total dissolved gas concentrations
shall not exceed 110 percent of the satura-
tion value for gases at the existing atmo-
spheric and hydrostatic pressures at any
point of sample collection.
  (D) Temperature—no  measurable
change from natural conditions.
  (E) pH—no  measurable  change from
natural conditions.
  (F) Turbidity shall  not exceed 5 NTU
over natural conditions.
  (G) Toxic, radioactive, nonconvention-
al, or deleterious material concentrations
shall be less than those which may affect
public health, the natural aquatic environ-
ment, or  the desirability of the water for
any  use.
  (6) Special  Resource  Water  Class
(SRW)—
  (i) General  characteristics. These  are
fresh or  saline waters which comprise a
special  and unique resource to the Reser-
vation.  Water quality of this class will be
varied  and unique as determined by the
Regional  Administrator  in  cooperation
with the  Tribes.
  (ii) Designated uses.  The designated
uses include, but  are not limited to, the
following:
  (A) Wildlife habitat.
  (B) Natural  foodchain maintenance.
  (iii) Water quality criteria.
  (A) Enterococci bacteria densities shall
not  exceed natural conditions.
  (B) Dissolved oxygen—shall  not  show
any  measurable  decrease  from natural
conditions.
  (C) Total dissolved gas shall not  vary
from natural conditions.
  (D) Temperature—shall not show any
measurable  change from natural  condi-
tions.
  (E) pH shall not show any measurable
change from natural conditions.
  (F) Settleable solids shall not show any
change from natural conditions.
  (G) Turbidity shall not exceed  5 NTU
over natural conditions.
  (H) Toxic,  radioactive,  or deleterious
material concentrations shall not  exceed
those found under natural  conditions.
  (g) General Classifications.  General
classifications applying to various surface
waterbodies not specifically classified un-
der §131.35(h) are as follows:
  (1)A11 surface waters  that are tribu-
taries to Class  I  waters  are  classified
Class I, unless otherwise classified.
  (2) Except for those specifically classi-
fied otherwise, all lakes with existing aver-
age concentrations less than  2000 mg/L
TDS and their feeder streams on the Col-
ville  Indian Reservation are  classified as
Lake Class and Class I, respectively.
  (3) All  lakes on  the  Colville  Indian
Reservation with existing average concen-
trations of  TDS  equal to or exceeding
2000 mg/L and their feeder streams are
classified as  Lake  Class and Class  I  re-
spectively  unless  specifically  classified
otherwise.
  (4) All reservoirs  with  a  mean deten-
tion time of greater  than 15 days are clas-
sified Lake Class.
  (5) All reservoirs  with  a  mean deten-
tion time of  15 days or less are classified
the same  as  the  river  section in which
they  are located.
  (6) All reservoirs  established on pre-ex-
isting lakes are classified as Lake Class.
  (7) All  wetlands  are  assigned  to the
Special Resource Water Class.
  (8) All other waters not  specifically  as-
signed to a classification of the reservation
are classified as Class II.
  (h) Specific Classifications.  Specific
classifications for surface  waters of the
Colville Indian Reservation are as follows:
(1) Streams:
  Alice Creek	   Class III
  Anderson Creek  	   Class III
  Armstrong Creek	   Class III
  Barnaby Creek	    Class II
  Bear Creek	   Class 111
  Beaver Dam Creek	   Class II
  Bridge Creek	    Class II
  Brush Creek	    Class III
  Buckhorn Creek	   Class III
  Cache Creek	   Class III
  Canteen Creek	   Class I
  Capoose Creek	   Class III
  Cobbs Creek	   Class III
  Columbia River from Chief Joseph
   Dam to Wells Oam
Columbia River from northern Res-
  ervation boundary to Grand Cou-
  lee Dam (Roosevelt Lake)
Columbia River from Grand  Coulee
  Dam to Chief Joseph Dam
Cook Creek  .     .              Class I
Cooper Creek .                   Class III
Cornstalk Creek                  Class III
Cougar Creek...              Class I
Coyote Creek	              Class II
Deerhorn Creek  . .            .    Class III
Dick Creek      .        ....    Class III
Dry Creek..            . .       Class I
Empire Creek	            Class III
Faye Creek	        Class I
Forty Mile Creek ...                Class III
Gibson Creek ...                   Class I
Gold Creek  .      .             Class II
Granite Creek  .    .             Class II
Grizzly Creek .  ..  .             Class III
Haley Creek	             Class III
Hall Creek	             Class II
Hall Creek, West Fork              Class I
Iron Creek   .                   Class III
Jack Creek    .                  Class III
Jerred Creek	         .       Class I
Joe Moses Creek.            .    Class III
John Tom Creek.  .               Class III
Jones Creek	                Class I
Kartar Creek	             Class III
Kmcaid Creek	       Class III
King Creek	     .   .          Class III
Klondyke Creek	        Class I
Lime Creek 	    Class III
Little Jim Creek .                  Class III
Little Nespelem       .            Class II
Louie Creek..     . .              Class III
Lynx Creek	       Class II
Manila Creek..   .                 Class III
McAllister Creek   .               Class III
Meadow Creek .                  Class III
Mill Creek 	            Class II
Mission Creek.. .    .            Class III
Nespelem River       .            Class II
Nez Perce Creek      .            Class III
Nine Mile Creek      .            Class II
Nineteen Mile Creek               Class III
No Name Creek                  Class II
North Nanamkm Creek       .       Class III
North Star Creek                  Class III
Okanogan River from  Reservation   Class II
  north boundary to Columbia River
Olds Creek  ....      ....    Class I
Omak Creek	      Class II
Onion Creek	            Class II
Parmenter Creek     ..  .          Class III
Peel Creek	          Class III
Peter Dan Creek	       Class III
Rock Creek   .  .   ..           Class I
San Poil River.  .  .               Class I
Sanpoil, River West Fork	    Class II
Seventeen Mile Creek  .   ..       Class III
Silver Creek ..  .   .               Class III
Sitdown Creek	     Class III
Six Mile Creek	          Class III
South Nanamkm Creek .           Class III
Spring Creek	     Class III
Stapaloop Creek.    . .           Class III
Stepstone Creek                  Class III
Stranger Creek                   Class II
Strawberry Creek.   .    .  .      Class III
Swimptkm Creek	    Class III
Three Forks Creek	       Class I
Three Mile Creek	    Class III
Thirteen Mile Creek	        Class II
Thirty Mile Creek       .           Class II
Trail Creek	     .      Class III
Twentyfive Mile Creek	       Class III
Twentyone Mile Creek  .  .          Class III
Twentythree Mile Creek  .           Class III
Wannacot Creek    .    .. .       Class III

-------
  weiis creek	     Classl           LaFieurtake	      LC             § 131.36 Toxics  criteria  for  those states
  Whitelaw Creek	   Class III          Little Goose Lake	    LC             *          . .      ...  „.     ....    .  .
  vwmont creek	     class ii          Little Own, Lake 	    LC              not  complying with Clean Water  Act
(2) Lakes.                                         McGinnis Lake	    LC              section 303(cX2XB).
  Apex Lake	   LC              Nicholas Lake	    LC
  Big Goose Lake	   LC              Omak Lake	    SRW                                  .
  Bourgeau Lake	   LC              OWN Lake  	    SRW             (a) Scope. This section is  not a general
  Buffalo Lake	     LC              Peniey Lake	    SRW           promulgation  of the section 304(a) crite-
  CodyLake	        LC              Rebecca Lake	       LC              •«••-..-     n .   .   u . •
  Crawfish Lakes	     LC              Round Lake .     .                LC             na "°r  priority tOXIC  pollutants but IS re-
  camiiieLake      	    LC              Simpson Lake	    LC             stricted  to specific pollutants  in specific
  Elbow Lake.      	          LC              Soap Lake	     LC             Ctotoc
  Fish Lake....       ....        LC              Sugar Lake                      LC             Oldies.
  Gold Lake       	         LC              Summit Lake            ...      LC               fh\(\\FPA'v Sprtinn 1CI4(n\ Critrrin
  Great Western Lake	         LC              Twin Lakes	     SRW             l°MU &rA S Section lV4\a) Criteria
  Johnson Lake	     LC                                                           for Priority Toxic Pollutants.

-------
r*



#) COMPOUND CAS
Number
FRESH

Criterion
Maximum
Cone, d
(ug/L)
81
a
WATER

Criterion
Continuous
Cone, d
(ug/L)
U
SALTWATER

Criterion Criterion
Maximum Continuous
Cone, d Cone, d
(ug/L) (ug/L)
L/
HUMAN HEALTH
(10 risk for carcinogens)
For Consumption of:
Water & Organisms
Organisms Only
(ug/L) (ug/L)
B2 C1 C2 01 02
1 Antimony
2 Arsenic
3 Beryllium
4 Cadmi urn
5a Chromium (III)
b Chromium (VI)
6 Copper
7 Lead
8 Mercury
9 Nickel
10 Selenium
11 Silver
12 Thallium
13 Zinc
14 Cyanide
15 Asbestos
16 2,3,7,8-TCOD (Dioxin)
17 Acrolein
18 AcrylonitrHe
19 Benzene
20 Bromoform
21 Carbon Tetrachloride
22 Chlorobenzene
23 Chlorodibromomethane
24 Chloroethane
25 2-Chloroethytvinyl Ether
26 Chloroform
27 Dichlorobromomethane
7440360
7440382
7440417
7440439
16065831
18540299
7440508
7439921
7439976
7440020
7782492
7440224
7440280
7440666
57125
1332214
1746016
107028
107131
71432
75252
56235
108907
124481
75003
110758
67663
75274

360 m 190 m

3.9 e,m 1.1 e,m
1700 e,m 210 e,m
16 m 11m
18 e,m 12 e,m
82 e,m 3.2 e,m
2.4 m 0.012 i
1400 e,m 160 e,m
20 5
4.1 e,m

120 e,m 110 e,m
22 5.2










1 i



69 m 36 m

43 m 9.3 m

1100 m 50 m
2.9 m 2.9 m
220 m 8.5 m
2.1 m 0.025 i
75 m 8.3 m
300 m 71 m
2.3 m

95 m 86 m
1 1













14
0.018
n
n
n
n

n
0.14
610
n

1.7

700
7,000,000
0.000000013
320
0.059
1.2
4.3
0.25
680
0.41


5.7
0.27
a 4300 a
a,b,c 0.14 a,b,c
n
n
n
n

n
0.15
a 4600 a
n

a 6.3 a

a 220000 a,j
fibers/L k
c 0.000000014 c
780
a,c 0.66 a,c
a.c 71 a,e
a.c 360 a.c
a,c 4.4 a.c
a 21000 a,j
a.c 34 a.c


a.c 470 a,c
a.c 22 a.c

-------
"
(#) COMPOUND CAS
Number
-
FRESHWATER
Criterion Criterion
Maximum Continuous
Cone, d Cone, d
(ug/L) (ug/L)
B1 B2
SALTWATER
Criterion Criterion
Maximum Continuous
Cone, d Cone, d
(ug/L) (ug/L)
C1 C2
D
HUJAN HEALTH
(10 risk for carcinogens)
For Consumption of:
Water & Organisms
Organisms Only
(ug/L) (ug/L)
D1 D2
28 1,1-Oich loroethane
29 1,2-Dichloroethane
30 1,1-Dichloroethylene
31 1,2-Dichloropropane
32 1 ,3-Dichloroproovlene
33 Ethyl benzene
34 Methyl Bromide
35 Methyl Chloride
36 Methylene Chloride
37 1.1.2L2-Tetrach loroethane
38 Tetrachloroethylene
39 Toluene
40 1,2-Trans-Dichloroethylene
41 1,1,1-Trichloroethane
42 1,1.2-Trichloroethane
43 Trichloroethylene
44 Vinyl Chloride
45 2-Chlorophenol
46 2,4-Dichlorophenol
47 2.4-DimethylDhenol
48 2-Methyl-4,6-Dinitrophenol
49 2,4-Dinitrophenol
50 2-Nitrophenol
51 4-Nitrophenot
52 3-Methyl-4-Chlorophenol
53 Pentacnlorophenol
54 Phenol
55 2,4,6-Trichlorophenol
56 Acenaphthene
75343
107062
75354
78875
542756
100414
74839
74873
75092
79345
127184
108883
156605
71556
79005
79016
75014
95578
120832
105679
534521
51285
88755
100027
59507
87865
108952
88062
83329

























20 f 13 f




























13 7.9




0.38 a.c
0.057 a,c

10 a
3100 a
48 a
n
4.7 a,c
0.17 a^c
0.8 c
6800 a

n
0.60 a.c
2.7 c
2 c

93 a

13.4
70 a



0.28 a.c
21000 a
2.1 a,c


99 a,c
3.2 a.c

1700 a
29000 a
4000 a
n
1600 a.c
11 a.c
8.85 c
200000 a

n
42 a.c
81 c
525 c

790 a. j

765
14000 a



8.2 a.c
4600000 a.j
6.5 a.c


-------
A
#) COMPOUND CAS
Number
FRESHWATER
Criterion Criterion
Max i nun Continuous
Cone, d Cone, d
(ug/L) (ug/L)
B1 B2
SALTWATER
Criterion Criterion
Max i mum Continuous
Cone, d Cone, d
(ug/L) (ug/L)
C1 C2
H U_M A N HEALTH
(10 risk for carcinogens)
For Consumption of:
Water & Organisms
Organisms Only
(ug/L) (ug/L)
01 02
57 Acenaphthytene 208968
58 Anthracene 120127
59 Benzidine 92875
60 Benzo(a)Anthracene 56553
61 Benzo(a)Pyrene 50328
62 Benzo(b)Fluoranthene 205992
63 Benzo(ghi)Perylene 191242
64 Benzo(IOFluoranthene 207089
65 Bis(2-Chtoroethoxy)Methane 111911
66 Bis(2-Chloroethyl)Ether 111444
67 Bis(2-Chloroisopropyl)Ether 108601
68 Bis(2-Ethylhexyt)Phthalate 117817
69 4-Bromophenyt Phenyl Ether 101553
70 Butylbenzyl Phthalate 85687
71 2-Chloronaohthalene 91587
72 4-Chlorophenyl Phenyl Ether 7005723
73 Chrysene 218019
74 Dibenzo(a,h)Anthracene 53703
75 1,2-Dichlorobenzene 95501
76 1,3-Dichtorobenzene 541731
77 1,4-Dichlorobenzene 106467
78 3,3'-Dichlorobenzidine 91941
79 Diethyl Phthalate 84662
80 Dimethyl Phthalate 131113
81 Di-n-Butyl Phthalate 84742
82 2,4-Dinitrotoluene 121142
83 2,6-Dinitrotoluene 606202
84 Oi-n-Octyl Phthalate 117840
85 1,2-Diphenylhydrazine 122667





























i
i
j 9600 a
| 0.00012 a,c
| 0.0028 c
\ 0.0028 c
| 0.0028 c
i
i
| 0.0028 c
i
i
| 0.031 a.c
j 1400 a
I 1.8 a.c
i
i
i
i
i
i
i
i
! 0.0028 c
| 0.0028 c
! 2700 a
| 400
| 400
| 0.04 a.c
| 23000 a
| 313000
! 2700 a
! 0.11 c
i
i
i
i
! 0.040 a,c

110000 a
0.00054 a,c
0.031 c
0.031 c
0.031 c

0.031 c

1.4 a.c
170000 a
5.9 a,c




0.031 c
0.031 c
17000 a
2600
2600
0.077 a,c
120000 a
2900000
12000 a
9.1 c


0.54 a.c

-------
#) COMPOUND CAS .
Number
FRESHWATER
Criterion Criterion
Maximum Continuous
Cone, d Cone, d
(ug/L) (ug/L)
B1 82
SALTWATER
Criterion Criterion
Maximum Continuous
Cone, d Cone, d
(ug/L) (ug/L)
C1 C2
u
H U_M A N HEALTH
(10 risk for carcinogens)
For Consumption of:
Water & Organisms
Organi sms Only
(ug/L) (ug/L)
01 D2
86 Fluoranthene
87 Fluorene
88 Hexachlorobenzene
89 Hexachlorobutadiene
90 Hexachtorocyctooentadiene
91 Hexachloroethane
92 Indeno(1,2,3-cd)Pyrene
93 I sophorone
94 Naphthalene
95 Nitrobenzene
96 N-Nitrosodimethylamine
97 N-Hitrosodi-n-Propylamine
98 N-Nitrosodiphenylamine
99 Phenanthrene
100 Pyrene
101 1,2,4-Trichlorobenzene
102 Aldrin
103 alpha-BHC
104 beta-BHC
105 gamma -BHC
106 delta-BHC
107 Chlordane
108 4-4'-DDT
109 4,4'-DDE
110 4.4'-DDD
111 Oieldrin
112 alpha-Endosulfan
113 beta-Endosulfan
206440
86737
118741
87683
77474
67721
193395
78591
91203
98953
62759
621647
86306
85018
129000
120821
309002
319846
319857
58899
319868
57749
50293
72559
72548
60571
959988
33213659
i








L






3 g


2 g 0.08 g

2.4 g 0.0043 g
1.1 g 0.001 g

i 	
2.5 g 0.0019 g
0.22 g 0.056 g
0.22 g 0.056 g
i















1.3 g


0.16 g

0.09 g 0.004 g
0.13 g 0.001 g


0.71 g 0.0019 g
0.034 g 0.0087 g
0.034 g 0.0087 g
j 300 a
1300 a
0.00075 a,c
0.44 a,c
240 a
1.9 a,c
0.0028 c
8.4 a,c

17 a
0.00069 a,c

5.0 a,c

960 a

0.00013 a,c
0.0039 a,c
0.014 a,c
0.019 c

0.00057 a,c
0.00059 a,c
0.00059 a,c
0.00083 a.c
0.00014 a.c
0.93 a
0.93 a
370 a
14000 a
0.00077 a,c
50 a,c
17000 a.j
8.9 a,c
0.031 c
600 a,c

1900 a.i
8.1 a.c

16 a.c

11000 a

0.00014 a.c
0.013 a.c
0.046 a,c
0.063 c

0.00059 a.c
0.00059 a.c
0.00059 a.c
0.00084 a.c
0.00014 a,c
2.0 a
2.0 a

-------
A
(#) COMPOUND
114 Endosulfan Sulfate
115 Endrin
116 Endrin Aldehyde
117 Heptachlor
118 Heptachlor Epoxide
119 PCB-1242
120 PCS- 1254
121 PCB-1221
122 PCB-1232
123 PCB-1248
124 PCB-1260
125 PCB-1016
126 Toxaphene
I
CAS
Number
1031078
72208
7421934
76448
1024573
53469219
11097691
11104282
11141165
12672296
11096825
12674112
D
FRESHWATER
Criterion Criterion
Maximum Continuous
Cone, d Cone, d
(ug/L) (ug/L)
B1 B2

0.18 g 0.0023 g
i
i
0.52 g 0.0038 g |
0.52 g 0.0038 q
0.014 g
0.014 g
0.014 g
0.014 g j
0.014 g |
0.014 g
0.014 g
8001352 | 0.73 0.0002
i<
SALTWATER HUMAN
(10"° risk
u
HEALTH
for carcinogens)
Criterion Criterion For Consumption of:
Maximum Continuous Water & Organisms
Cone, d Cone, d Organisms Only
(ug/L) (ug/L) (ug/L) (ug/L)
C1 C2 D1 D2

0.037 g 0.0023 g

0.053 g 0.0036 g
0.053 g 0.0036 g
0.03 g
0.03 g
0.03 g
0.03 g
0.03 g
0.03 g
0.03 g
0.21 0.0002
0.93
0.76
0.76
0.00021
0.00010
0.000044
0.000044
0.000044
0.000044
0.000044
0.000044
0.000044
0.00073
a 2.0 a
a 0.81 a.j
a 0.81 a.j
a,c 0.00021 a,c
a.c 0.00011 a,c
a,c 0.000045 a.c
a,c 0.000045 a,c
a,c 0.000045 a.c
a.c 0.000045 a.c
a.c 0.000045 a.c
a.c 0.000045 a.c
a,c 0.000045 a.c
a.c 0.00075 a.c
Total No.  of Criteria (h) =
24
29
23
27
                                                        91
                                                           90

-------
  Footnotes:
  a.  Criteria revised to reflect current
agency qi* or RfD,  as  contained in the
Integrated  Risk  Information  System
(IRIS). The fish  tissue  bioconcentration
factor (BCF) from the 1980 criteria docu-
ments was retained in all cases.
  b.  The criteria refers to the  inorganic
form only.
  c. Criteria in the matrix based on carci-
nogenicity (10~* risk). For a risk level of
10'5,  move the decimal point in the matrix
value one place to the right.
  d.  Criteria  Maximum  Concentration
(CMC) = the highest concentration of a
pollutant to which aquatic life can be ex-
posed for a short period of time (1-hour
average) without  deleterious effects. Cri-
teria Continuous Concentration  (CCC) =
the highest concentration of a pollutant to
which aquatic life can be exposed for an
extended period of time (4 days) without
deleterious effects, ug/L  =  micrograms
per liter
  e.  Freshwater aquatic life criteria for
these metals are expressed as a function
of total hardness  (mg/L), and as a func-
tion  of the pollutant's water  effect ratio,
WER, as  defined in §131.36(c). The
equations  are  provided in matrix  at
§131.36(b)(2). Values displayed above in
the matrix correspond to a total hardness
of 100 mg/L and a  water effect ratio of
1.0.
  f.  Freshwater aquatic life criteria for
pentachlorophenol are expressed  as  a
function of pH, and are calculated as fol-
lows. Values displayed above in the  ma-
trix correspond to a pH of 7.8.
CMC = exp(1.005(pH) - 4.830) CCC =
     exp(1.005(pH) - 5.290)
  g.  Aquatic life criteria for these  com-
pounds were issued in 1980 utilizing the
1980 Guidelines for criteria development.
The  acute  values  shown are final acute
values (FAV)  which by the 1980 Guide-
lines  are  instantaneous  values  as con-
trasted with a CMC which is a one-hour
average.
  h. These totals simply sum the criteria
in each column. For aquatic life, there are
30  priority  toxic  pollutants with some
type of freshwater or saltwater, acute or
chronic criteria.  For human  health, there
are 91 priority toxic pollutants with either
"water + fish"  or "fish  only"  criteria.
Note that these totals count  chromium as
one pollutant even though EPA has devel-
oped criteria based on two valence  states.
In the matrix, EPA has assigned numbers
5a and 5b to the criteria for  chromium to
reflect the fact that the list of 126 priority
toxic pollutants includes only a single list-
ing for chromium.
  i. If the CCC for total mercury exceeds
0.012 ug/L more  than  once in a  3-year
period in  the ambient water, the  edible
portion of aquatic species of concern must
be  analyzed to determine  whether the
concentration of methyl mercury exceeds
the FDA action  level (1.0 mg/kg). If the
FDA action  level  is exceeded, the State
must notify the appropriate EPA Region-
al Administrator, initiate a revision of its
mercury  criterion  in  its water quality
standards so as to protect designated uses,
and  take other appropriate action such as
issuance  of  a fish consumption  advisory
for the affected area.
  j.  No criteria for  protection of human
health from consumption of  aquatic orga-
nisms (excluding water) was presented in
the 1980 criteria document or in the 1986
Quality Criteria for Water. Nevertheless,
sufficient  information  was  presented in
the 1980 document to allow  a calculation
of a criterion, even though the results of
such  a calculation  were not  shown in the
document.
   k.  The criterion  for  asbestos  is the
MCL (56 FR 3526, January 30, 1991).
  1. This letter not used as a footnote.
  m.  Criteria for these metals are ex-
pressed  as a function of the water effect
ratio,  WER, as  defined in  40 CFR
131.36(c).
CMC = column Bl or Cl value X WER
CCC  = column B2 or C2 value X  WER
  n. EPA  is  not promulgating  human
health criteria for this contaminant. How-
ever,  permit authorities should address
this contaminant in  NPDES  permit ac-
tions using the State's existing narrative
criteria  for toxics.
  General Notes:
  1. This chart lists  all of EPA's priority
toxic  pollutants  whether  or  not criteria
recommendations are  available.  Blank
spaces indicate the absence of criteria rec-
ommendations. Because of variations  in
chemical nomenclature systems, this list-
ing of toxic pollutants does not duplicate
the listing in Appendix A of 40 CFR Part
423. EPA  has added the Chemical Ab-
stracts Service (CAS) registry numbers,
which provide a unique identification for
each chemical.
  2. The following chemicals have organ-
oleptic  based criteria recommendations
that are not included  on this  chart (for
reasons which are discussed in the pream-
ble): copper, zinc, chlorobenzene,  2-chlo-
rophenol,  2,4-dichlorophenol, acenaph-
thene,  2,4-dimethylphenol,  3-methyl-4-
chlorophenol,  hexachlorocyclopentadiene,
pentachlorophenol, phenol
  3.  For purposes  of  this rulemaking,
freshwater criteria and saltwater criteria
apply as specified in 40 CFR  131.36(c).
  (2) Factors for Calculating  Metals
Criteria
CMC=WER  exp|mA[ln(hardness)]+bA)
    CCC = WER
    exp|mc[ln(hardness)]+bc)

-------
                           CMC=WER exp|mA[ln(hardness)]+bA| • CCC=WER exp|mc[ln(hardness)]+bc)

Cadmium 	
Copper 	
Chromium (III) 	
Lead 	
Nickel 	
Silver 	 	
Zinc 	

rru
1 128
09422
08190
1 273
08460
1.72
08473

DA
-3828
-1 464
3688
-1 460
33612
-652
0 8604

mc
07852
08545
08190
1 273
08460

0 8473

be
-3490
1 465
1 561
4 705
1 1645

0 7614

  Note- The term "exp" represents the base e exponential function
   (c) Applicability.
   (I) The criteria in paragraph (b) of this
section apply to the States' designated
uses cited in paragraph  (d) of this section
and supersede any criteria adopted by the
State, except when State regulations con-
tain criteria which are more  stringent for
a particular use in which case the State's
criteria will continue to apply.
   (2) The criteria established in  this sec-
tion are subject to the State's  general
rules of applicability in the same  way  and
to the same extent as are the other numer-
ic toxics criteria when applied to the same
use classifications including mixing zones,
and low flow values below which  numeric
standards  can  be  exceeded in  flowing
fresh waters.
   (i) For all waters with mixing zone reg-
ulations  or implementation  procedures,
the criteria apply at the appropriate loca-
tions within or at the  boundary of  the
mixing zones; otherwise the criteria apply
throughout  the waterbody  including at
the  end of any discharge  pipe, canal or
other discharge  point.
   (ii) A  State  shall not use a low flow
value below which numeric standards  can
be exceeded that is less stringent  than the
following for waters suitable for the estab-
lishment of low flow return  frequencies
(i.e., streams and rivers):
               Aquatic Life
Acute criteria (CMC)    1 Q 10 or 1 B 3
Chronic criteria (CCC)   7 Q 10 or 4 B 3
              Human Health
Non-carcinogens
Carcinogens
30 Q 5
Harmonic mean flow
Where:
  CMC—criteria maximum  concentra-
tion—the water quality criteria to protect
against acute effects in aquatic life and is
the highest instream concentration  of a
priority  toxic pollutant  consisting  of a
one-hour average  not to be exceeded more
than once every three years on the aver-
age;
   CCC—criteria  continuous concentra-
tion—the water quality criteria to protect
against chronic effects in  aquatic life  is
the highest instream concentration  of a
priority toxic  pollutant consisting of a 4-
day average not to be exceeded more than
once every three years on the average;
   1 Q 10 is the lowest one day flow with
an average recurrence frequency of once
in 10 years determined hydrologically;
   I B 3 is biologically based and indicates
an allowable exceedence of once every 3
years. It is determined by EPA's comput-
erized method (DFLOW model);
   7 Q 10 is the lowest average 7 consecu-
tive day low  flow  with an  average recur-
rence frequency of once in  10 years deter-
mined hydrologically;
   4 B 3 is biologically based and indicates
an allowable exceedence for 4 consecutive
days once every 3  years. It is determined
by  EPA's   computerized  method
(DFLOW model);
   30 Q 5 is the lowest average 30 consec-
utive day low  flow with an average recur-
rence frequency of once in 5 years deter-
mined hydrologically; and  the  harmonic
mean flow is a long term mean flow value
calculated by  dividing the number of dai-
ly  flows analyzed by the  sum  of  the
reciprocals of those daily flows.
   (iii) If a State does not have such a low
flow value for numeric standards compli-
ance, then none shall apply and the crite-
ria included in paragraph (d) of this sec-
tion herein apply at all flows.
   (3) The aquatic  life criteria in the ma-
trix in paragraph (b)  of this section apply
as follows:
   (i) For waters in which  the salinity is
equal to or less than  1 part per thousand
95% or more  of the time,  the  applicable
criteria are the freshwater criteria in Col-
umn B;
   (ii) For waters in which the salinity is
equal to or greater  than 10 parts per thou-
sand 95% or more of the time, the appli-
cable criteria are the saltwater criteria in
Column C; and
   (iii) For waters in which the salinity is
between 1 and  10 parts per thousand  as
defined in paragraphs (c)(3) (i) and (ii) of
this section, the applicable criteria are the
more  stringent of  the  freshwater  or
saltwater  criteria. However, the Regional
Administrator may approve the use of the
alternative freshwater or saltwater crite-
ria if scientifically defensible information
and data  demonstrate that on a site-spe-
cific basis the biology of the waterbody is
dominated by freshwater  aquatic life and
that freshwater criteria are more appro-
priate;  or conversely,  the biology of the
waterbody  is  dominated by saltwater
aquatic life and that saltwater criteria are
more appropriate.
   (4) Application of metals criteria.
   (i)  For purposes of calculating freshwa-
ter aquatic life criteria  for metals  from
the equations in paragraph (b)(2) of this
section, the  minimum  hardness allowed
for use in  those equations shall not be less
than 25 mg/1, as calcium  carbonate, even
if the actual ambient hardness is less than
25 mg/1 as calcium carbonate. The maxi-
mum  hardness value for use  in those
equations  shall  not  exceed  400 mg/1  as
calcium carbonate, even if the actual am-
bient  hardness is  greater than 400 mg/1
as calcium  carbonate.  The same  provi-
sions  apply for calculating the metals cri-
teria  for the comparisons provided for  in
paragraph (c)(3)(iii) of this section.
   (ii) The  hardness  values used shall be
consistent with the design discharge con-
ditions established in paragraph (c)(2)  of
this section for flows and  mixing zones.
   (iii) The criteria for metals (compounds
#1-#13 in paragraph (b)  of this section)
are expressed  as  total recoverable.  For
purposes of calculating aquatic life crite-
ria for metals from the equations in foot-
note  M. in the criteria  matrix in para-
graph (b)(l) of this section and the equa-
tions  in paragraph (b)(2) of this section,
the water-effect ratio is  computed  as  a

-------
specific pollutant's acute or chronic toxici-
ty values measured in water from the site
covered by  the standard, divided by the
respective acute or chronic toxicity value
in laboratory  dilution water.  The water-
effect ratio  shall be  assigned  a  value  of
1.0, except where the permitting authori-
ty assigns a different value that protects
the designated  uses  of the water body
from the toxic effects  of the pollutant, and
is derived from suitable tests  on sampled
water representative  of conditions in the
affected  water body, consistent  with the
design discharge  conditions established in
paragraph (c)(2) of this section. For pur-
poses of this  paragraph, the  term  acute
toxicity value is  the  toxicity  test results,
such as  theCOncttrtfrti.tic.1 M*o|t
-------
  Use classification
Delaware River zones
  1C, 1D, 1E, 2, 3, 4, 5
  and  Delaware  Bay
  zone 6
  Applicable criteria

Column C1 —all except
  #102, 105, 107, 108,
  111, 112,  113,  115,
  117, and 118.
Column C2—all except
  #105, 107, 108, 111,
  112, 113,  115,  117,
  118, 119,  120,  121,
  122, 123,  124, and
  125.
Column  D2—all  at a
  10-'risk level except
  #23, 30, 37, 38, 42,
  68, 89,  91, 93,  104,
  105; #23,  30, 37, 38,
  42, 68, 89,  91,  93,
  104, 105,  at a  10-'
  risk level
These  classifications
  are assigned the cri-
  teria in

Column B1—all
Column B2—all
Column  D1—all  at a
  10-* risk level except
  #23, 30, 37, 38, 42,
  68, 89,  91, 93. 104,
  105; #23.  30, 37, 38,
  42. 68, 89,  91, 93,
  104, 105,  at a  10-5
  risk level.
Column  D2—all  at a
  10-'risk level except
  #23, 30, 37, 38, 42,
  68, 89,  91, 93, 104,
  105, #23,  30, 37, 38,
  42, 68, 89,  91. 93,
  104, 105,  at a  10-5
  risk level.
These  classifications
  are assigned the cri-
  teria in:
Column C1—all
Column C2—all
Column  D2—all  at a
  10-* risk level except
  #23, 30, 37, 38, 42,
  68, 89,  91, 93, 104,
  105; #23,  30, 37, 38,
  42, 68, 89,  91, 93.
  104, 105,  at a  10-s
  risk level
   (iii) The human health criteria shall be
applied at the State-proposed 10-6 risk lev-
el for EPA  rated Class A,  Bi,  and  B2
carcinogens; EPA rated  Class C carcino-
gens shall be applied at 10'5 risk level. To
determine appropriate value for carcino-
gens, see  footnote c. in the matrix in para-
graph (b)(l) of this section.
   (4) Puerto Rico. EPA Region 2.
   (i) All  waters assigned to the following
use classifications in the  Puerto Rico Wa-
ter Quality Standards (promulgated  by
Resolution Number  R-83-5-2) are sub-
Delaware River zones
  3.4, and 5, and Dela-
  ware Bay zone 6
ject to the criteria in paragraph (d)(4)(ii)
of this section, without exception.
  Article 2.2.2—Class SB
  Article 2.2.3—Class SC
  Article 2.2.4—Class SD
  (ii) The following criteria from the ma-
trix in  paragraph  (b)(l) of  this section
apply to the  use classifications identified
in paragraph (d)(4)(i) of this section:

  Use classification       Applicable criteria

Class SD              This Classification  is
                        assigned the  criteria
                        in:
                      Column B1—all, ex-
                        cepf 10.  102,  105,
                        107, 108, 111, 112,
                        113,  115, 117, and
                        126
                      Column B2—all, ex-
                        cept: 105, 107, 108.
                        112,  113, 115, and
                        117
                      Column 01—all, ex-
                        cept: 6, 14, 105, 112,
                        113, and 115.
                      Column D2—all, ex-
                        cept: 14,  105,  112,
                        113, and 115.
Class SB, Class SC     This Classification  is
                        assigned the  criteria
                        in:
                      Column C1—all, ex-
                        cept 4, 5b, 7, 8, 10,
                        11,13,102,105.107,
                        108,  111, 112, 113,
                        115, 117. and 126.
                      Column C2—all, ex-
                        cept  4, 5b,  10, 13,
                        108,  112, 113, 115,
                        and  117.
                      Column D2—all, ex-
                        cept: 14,  105,  112,
                        113, and 115.
   (iii) The human health criteria shall be
applied at the State-proposed 10'5 risk lev-
el. To  determine appropriate  value  for
carcinogens, see footnote c, in the criteria
matrix in paragraph (b)( I) of this section.
   (5) District of Columbia.  EPA Region
3.
   (i) All  waters assigned to  the  following
use classifications in chapter II Title 21
DCMR,  Water  Quality Standards of the
District  of Columbia are subject to the
criteria in paragraph (d)(5)(ii) of this sec-
tion, without exception:
   1101.2 Class C waters
   (ii) The following criteria  from the ma-
trix  in  paragraph (b)(l) of this section
apply to the use  classification identified in
paragraph (d)(5)(i)  of this section:
                                                                                          Use classification       Applicable criteria

                                                                                        Class C                This classification  is
                                                                                                                assigned  the  addi-
                                                                                                                tional criteria in:
                                                                                                              Colum  B2—#10, 118,
                                                                                                                126.
                                                                                                              Colum  D1—#15,  16,
                                                                                                                44,67,68,79,80,81,
                                                                                                                88, 114, 116, 118.
                                                                                                              Colum D2—all.
   (iii) The human health criteria shall be
applied at the State-adopted 10-6 risk lev-
el.
   (6) Florida. EPA  Region 4.
   (i) All  waters assigned to the  following
use  classifications in Chapter 17-301 of
the  Florida  Administrative  Code  (i.e.,
identified in Section  17-302.600) are sub-
ject  to the criteria in paragraph (d)(6)(ii)
of this section, without exception:
   Class  I
   Class  II
   Class  III
   (ii) The following  criteria from the ma-
trix  paragraph (b)(l) of this section apply
to the use  classifications identified in
paragraph (d)(6)(i)  of this section:
                                                                                          Use classification

                                                                                        Class I
                                                                                        Class I
Class III (marine)
Class III (fresh water)
  Applicable criteria

This classification is
  assigned the criteria
  in.
Column D1—#16
This classification is
  assigned the criteria
  in:              . .
CO'O.IA OX-* Iff
This classification is
  assigned the criteria
  in:
Column D2—#16
   (iii) The human health criteria shall be
applied at the State-adopted 10'6 risk lev-
el.
   (7) Michigan, EPA Region 5.
   (i) All  waters assigned to the  following
use  classifications in  the Michigan  De-
partment of Natural Resources  Commis-
sion General  Rules,  R 323.1100  designat-
ed uses, as defined at R  323.1043. Defini-
tions; A to N, (i.e., identified in Section
(g) "Designated use") are subject  to the
criteria in paragraph (d)(7)(ii) of this sec-
tion, without  exception:
   Agriculture
   Navigation
   Industrial Water Supply
   Public  Water Supply  at the  Point of
     Water Intake
   Warmwater Fish

-------
  Other Indigenous Aquatic Life  and
    Wildlife
  Partial Body Contact Recreation
  (ii) The following criteria from the ma-
trix in  paragraph  (b)(l) of this  section
apply to the use classifications identified
in paragraph (d)(7)(i) of this section

  Use classification       Applicable criteria

Public  Water supply     This classification is
                       assigned the criteria
                       in:
                        Column  B1—all,
                          Column  B2—all.
                          Column D1—all.
All other designations    These  classifications
                       are assigned the cri-
                       teria in:
                        Column B1—all,
                        Column  B2—all,
                          and
                         Column D2—all
   (iii) The human health criteria shall be
applied at the State-adopted 10'5 risk lev-
el.  To  determine appropriate  value for
carcinogens, see footnote c in the criteria
matrix in paragraph (b)(l) of this section.
   (8) Arkansas, EPA Region 6.
   (i) All waters assigned to the following
use  classification  in  section  4C
(Watcrbody uses) identified in Arkansas
Department of  Pollution Control and
Ecology's Regulation No. 2 as amended
and entitled,  "Regulation  Establishing
Water Quality  Standards for Surface
Waters of the State  of Arkansas" are sub-
ject to the criteria in paragraph (d)(8)(ii)
of this section, without exception:
Extraordinary  Resource Waters
Ecologically Sensitive Watcrbody
Natural and Scenic Waterways
Fisheries:
(1)  Trout
(2)  Lakes and Reservoirs
(3)  Streams
   (a)  Ozark Highlands Ecoregion
   (b)  Boston Mountains Ecoregion
   (c)  Arkansas River Valley Ecoregion
   (d)  Ouachita Mountains Ecoregion
   (e)  Typical Gulf  Coastal Ecoregion
   (f)   Spring  Water-influenced  Gulf
     Coastal Ecoregion
   (g) Least-altered Delta Ecoregion
   (h) Channel-altered Delta Ecoregion
 Domestic Water Supply
   (ii) The following criteria from the ma-
 trix in  paragraph  (b)(l) of this section
 apply to the use classification identified in
 paragraph  (d)(8)(i) of this section:
  Use classification       Applicable criteria

Extraordinary  Re-
 source Waters
Ecologically  Sensitive
 Waterbody
Natural  and  Scenic
 Waterways
Fisheries.
   (1) Trout
   (2) Lakes and Res-
     ervoirs
   (3) Streams
     (a) Ozark High-
      lands  Ecore-
      gion
     (b) Boston Moun-
      tains Ecoregion
     (c) Arkansas Riv-
      er     Valley
      Ecoregion
     (d)   Ouachita
      Mountains
      Ecoregion
     (e) Typical Gulf
      Coastal Ecore-
      gion
     (f) Spring Water-
      influenced Gulf
      Coastal Ecore-
      gion
     (g) Least-altered
       Delta  Ecore-
      gion
     (h) Channel-al-    These  uses  are each
      tered   Delta     assigned the criteria
       Ecoregion         in—
                        Column B1— #4,
                          5a. 5b,  6, 7, 8, 9,
                          10, 11,  13, 14
                        Column B2— #4,
                          5a, 5b,  6, 7, 8, 9,
                          10, 13,  14
   (9) Kansas. EPA Region 7.
   (i) All waters assigned to the following
 use classification  in the Kansas Depart-
 ment of Health and Environment regula-
 tions, K.A.R. 28-16-28b through K.A.R.
 28-16-28f, are subject to  the criteria  in
 paragraph (d)(9)(ii) of this section, with-
 out exception.
 Section 28-16-28d
   Section (2)(A)—Special Aquatic  Life
      Use Waters
   Section  (2)(B)—Expected  Aquatic
      Life Use Waters
   Section  (2)(C)—Restricted  Aquatic
      Life Use Waters
   Section (3)—Domestic Water Supply
   Section  (6)(c)—Consumptive Recre-
      ation Use.
    (ii) The following criteria from the ma-
 trix in  paragraph  (b)(l)  of  this section
 apply to the use classifications identified
 in paragraph (d)(9)(i) of this section:
  Use classification       Applicable criteria

    Sections  (2)(A),   These  classifactions
      (2)(B),  (2)(C),     are each assigned all
      (6)(C)             criteria in-
                          Column  B1,  all
                           except  #9, 11,
                           13,  102,  105,
                           107,     108,
                           111-113,  115,
                           117, and 126;
                          Column  B2,  all
                           except  #9, 13,
                           105,  107, 108,
                           111-113,  115,
                           117,  119-125,
                           and 126; and
                          Column  D2,  all
                           except  #9,
                           112,  113, and
                           115.
Section (3)             This classification is
                       assigned all criteria
                       in;
                          Column  D1,  all
                           except  #9,  12,
                           112,  113, and
                            115.
  (iii) The human health criteria shall be
applied at the State-proposed 10~6 risk lev-
el.
  (10) California, EPA Region  9.
  (i) All waters assigned any aquatic life
or human health use classifications in the
Water Quality Control Plans for the vari-
ous  Basins of the State ("Basin Plans"),
as amended,  adopted  by the California
State Water Resources  Control  Board
("SWRCB"), except  for ocean  waters
covered by the  Water Quality Control
Plan for Ocean Waters  of California
("Ocean Plan")  adopted by the SWRCB
with resolution Number 90-27 on March
22,  1990,  are subject to the criteria  in
paragraph  (d)(10)(ii) of  this section,
without exception. These criteria amend
the  portions  of  the  existing  State stan-
dards contained  in the Basin Plans. More
particularly  these criteria  amend water
quality  criteria  contained  in  the Basin
Plan Chapters  specifying water  quality
objectives (the State equivalent  of federal
water quality criteria) for the toxic pollu-
tants identified  in paragraph (d)(10)(ii)
of  this section.  Although the  State has
adopted several  use designations for each
of  these waters, for purposes of  this ac-
tion, the specific standards to be applied
in  paragraph (d)(10)(ii) of  this section
are based on the presence in all waters of
some aquatic life designation and  the
presence or absence of the MUN  use des-
ignation  (Municipal and domestic  sup-
ply). (See Basin Plans for  more detailed
 use definitions.)

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All other designations
  Other Indigenous Aquatic Life  and
    Wildlife
  Partial Body Contact Recreation
  (ii) The following criteria from the ma-
trix in  paragraph (b)(l) of this  section
apply to the use classifications identified
in paragraph (d)(7)(i) of this section

  Use classification       Applicable criteria

Public Water supply     This classification is
                       assigned the criteria
                       in:
                        Column  B1—all,
                          Column  82—all,
                          Column D1—all.
                     These  classifications
                       are assigned the cri-
                       teria in:
                        Column B1—all,
                        Column  B2—all,
                          and
                        Column D2—all
  (iii) The human health criteria shall be
applied at the State-adopted 10'5 risk lev-
el.  To  determine appropriate value  for
carcinogens, see footnote c in the criteria
matrix in paragraph (b)(l) of this section.
  (8) Arkansas. EPA  Region 6.
  (i) All waters assigned to the following
use  classification   in  section   4C
(Watcrbody uses) identified in Arkansas
Department of  Pollution  Control  and
Ecology's Regulation  No. 2 as amended
and entitled,  "Regulation  Establishing
Water  Quality Standards  for  Surface
Waters of the State of Arkansas" are sub-
ject to the criteria in paragraph (d)(8)(ii)
of this section, without exception:
Extraordinary Resource Waters
Ecologically Sensitive  Waterbody
Natural and Scenic Waterways
Fisheries:
(I) Trout
(2) Lakes and  Reservoirs
(3) Streams
  (a) Ozark Highlands  Ecoregion
  (b) Boston Mountains Ecoregion
  (c) Arkansas River  Valley Ecoregion
  (d) Ouachita Mountains  Ecoregion
  (e) Typical  Gulf Coastal Ecoregion
  (f)  Spring   Water-influenced  Gulf
     Coastal Ecoregion
  (g) Least-altered  Delta Ecoregion
  (h) Channel-altered Delta Ecoregion
Domestic Water Supply
  (ii) The following criteria from  the ma-
trix in  paragraph  (b)(l) of this section
apply to the use classification identified in
paragraph  (d)(8)(i) of this  section:
  Use classification

Extraordinary  Re-
 source Waters
Ecologically Sensitive
 Waterbody
Natural  and Scenic
 Waterways
Fisheries'
   (1) Trout
   (2) Lakes and Res-
     ervoirs
   (3) Streams
     (a) Ozark  High-
      lands Ecore-
      gion
     (b) Boston Moun-
      tains Ecoregion
     (c) Arkansas Riv-
      er    Valley
      Ecoregion
     (d)   Ouachita
      Mountains
      Ecoregion
     (e) Typical Gulf
      Coastal Ecore-
      gion
     (f) Spring Water-
      influenced Gulf
      Coastal Ecore-
      gion
     (g) Least-altered
      Delta Ecore-
      gion
     (h) Channpi-al-
      tered   Delta
      Ecoregion
                                                                 Applicable criteria
                                                                These uses are each
                                                                  assigned  the criteria
                                                                  in—
                                                                   Column B1— #4,
                                                                     5a, 5b, 6, 7. 8, 9.
                                                                     10, 11, 13, 14
                                                                   Column B2— #4,
                                                                     5a, 5b, 6, 7, 8, 9,
                                                                     10, 13, 14
                                             (9) Kansas. EPA Region 7.
                                             (i) All waters assigned to the following
                                           use classification in the Kansas Depart-
                                           ment of Health and Environment regula-
                                           tions, K.A.R. 28-l6-28b through K.A.R.
                                           28-16-28f, are  subject to the criteria  in
                                           paragraph (d)(9)(ii) of this section, with-
                                           out exception.
                                           Section 28-16-28d
                                             Section (2)(A)—Special Aquatic  Life
                                                Use Waters
                                             Section  (2)(B)—Expected  Aquatic
                                                Life Use Waters
                                             Section  (2)(C)—Restricted  Aquatic
                                                Life Use Waters
                                             Section (3)—Domestic Water Supply
                                             Section  (6)(c)—Consumptive Recre-
                                                ation Use.
                                             (ii) The following criteria from the ma-
                                           trix  in paragraph  (b)(l)  of  this section
                                           apply to the  use classifications identified
                                           in  paragraph (d)(9)(i) of this section:
  Use classification       Applicable criteria

    Sections  (2)(A),   These  classifactions
      (2)(B),  (2)(C),     are each assigned all
      (6)(C)             criteria in.
                          Column 81,  all
                           except #9, 11,
                           13,  102,  105,
                           107,    108,
                           111-113,  115,
                           117, and 126;
                          Column 82,  all
                           except #9, 13,
                           105,  107,  108,
                           111-113,  115,
                           117,  119-125,
                           and 126; and
                          Column D2,  all
                           except   #9,
                           112,  113, and
                           115.
Section (3)             This classification is
                       assigned all criteria
                       in.
                          Column D1,  all
                           except #9,  12,
                           112,  113, and
                           115
  (iii) The human health criteria shall be
applied at the State-proposed 1O6 risk lev-
el.
  (10) California, EPA Region 9
  (i) All waters assigned any aquatic life
or human health use classifications in the
Water Quality Control Plans for ihe  vari-
ous  Basins of the State ("Basin Plans"),
as amended,  adopted  by the California
State  Water Resources Control  Board
("SWRCB"), except  for  ocean waters
covered  by the  Water Quality Control
Plan for Ocean  Waters  of  California
("Ocean Plan") adopted by the SWRCB
with resolution Number 90-27 on March
22,  1990,  are subject to the  criteria in
paragraph  (d)(10)(ii) of this section,
without exception. These criteria amend
the  portions  of the  existing  State  stan-
dards contained in the Basin Plans.  More
particularly  these criteria amend water
quality criteria contained in  the Basin
Plan Chapters  specifying  water quality
objectives (the State equivalent of federal
water quality criteria)  for the  toxic pollu-
tants identified in paragraph  (d)(lO)(ii)
of this  section. Although  the State has
adopted several use  designations for  each
of these waters, for purposes  of this ac-
tion, the specific standards to be applied
in paragraph (d)(10)(ii)  of  this section
are based on the presence in all waters of
some aquatic life  designation  and the
presence or absence of the MUN use des-
ignation (Municipal  and domestic  sup-
ply). (See  Basin Plans for more detailed
use definitions.)

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   (ii) The following criteria from the ma-
trix in paragraph  (b)(l) of  this  section
apply to  the water  and use  classifications
defined  in paragraph  (d)(IO)(i)  of this
section and identified  below.
                                  Water and use classification

Waters of the  State defined  as  bays or estuaries except the Sacramento-San Joaqum Delta and  San
  Francisco Bay
Waters of the Sacramento—San Joaqum Delta and waters of the State defined as inland (i e., all surface
  waters of the State not bays or estuaries or ocean) that include a MUN use designation
Waters of the State defined as inland without an MUN use designation
Waters of the San Joaqum River from the mouth of the Merced River to Vernahs
Waters of Salt Slough, Mud Slough (north) and the San Joaqum River, Sack Dam to the mouth of the
  Merced River
Waters of San Francisco Bay upstream to and including Suisun Bay and the Sacramento San Joaqum Delta
All inland waters of the United States or enclosed bays and estuaries that are waters of the United States
  that include an MUN use designation and that the State has either excluded or partially excluded from
  coverage under its Water Quality Control Plan for Inland Surface Waters of California, Tables 1 and 2, or
  its Water Quality Control Plan for Enclosed Bays and Estuaries  of California, Tables 1 and 2.  or has
  deferred applicability of those tables. (Category (a), (b), and (c) waters described on page 6 of Water
  Quality Control Plan for Inland Surface Waters of California or page 6 of its Water Quality Control Plan for
  Enclosed Bays and Estuaries of California.)
All inland waters of the United States that do not include an MUN use designation and that the State has
  either excluded or partially excluded  from coverage under its Water Quality Control Plan  for Inland
  Surface Waters of California, Tables 1  and 2, or has deferred applicability of these tables. (Category (a),
  (b), and (c) waters described on page 6 of Water Quality Control Plan Inland Surface Waters of California )
                                                               Applicable criteria
                                                                                                 These waters are assigned the criteria in:
                                                                                                      Column B1—pollutants 5a and 14
                                                                                                      Column B2—pollutants 5a and 14
                                                                                                      Column C1—pollutant 14
                                                                                                      Column C2—pollutant 14
                                                                                                      Column D2—pollutants 1, 12, 17, 18. 21,
                                                                                                        22, 29, 30, 32, 33, 37, 38, 42-44, 46, 48,
                                                                                                        49, 54, 59, 66, 67, 68, 78-82, 85, 89, 90,
                                                                                                        91,93,95, 96,98
                                                  These waters are assigned the criteria in:
                                                       Column 81—pollutants 5a and 14
                                                       Column B2—pollutants 5a and 14
                                                       Column D1—-pollutants, 1, 12, 15, 17, 18,
                                                         21. 22, 29, 30, 32, 33, 37, 38, 42-48, 49,
                                                         59, 66, 68, 78-82, 85, 89. 90, 91. 93, 95,
                                                         96,98

                                                  These waters are assigned the criteria in:
                                                       Column B1—pollutants 5a and 14
                                                       Column B2—pollutants 5a and 14
                                                       Column D2—pollutants 1,  12, 17, 18, 21,
                                                         22, 29, 30, 32. 33, 37, 38, 42-44, 46, 48,
                                                         49, 54, 59, 66, 67, 68, 78-82, 85, 89, 90.
                                                         91,93,95,96,98

                                                  In addition to the criteria assigned to these wa-
                                                    ters elsewhere in this rule, these waters are
                                                    assigned the criteria in:
                                                       Column B2—pollutant 10
                                                  In addition to the criteria assigned to these wa-
                                                    ters elsewhere in this rule, these waters are
                                                    assigned the criteria in:
                                                       Column B1—pollutant 10
                                                       Column B2—pollutant 10

                                                  These waters are assigned the criteria in-
                                                       Column B1—pollutants 5a, 10' and 14
                                                       Column B2—pollutants 5a, 10' and 14
                                                       Column C1—pollutant 14
                                                       Column C2—pollutant 14
                                                       Column D2—pollutants 1. 12, 17, 18, 21,
                                                         22, 29, 30, 32, 33, 37, 38, 42-44, 46, 48,
                                                         49, 54, 59, 66, 67, 68, 78-82, 85, 89, 90,
                                                         91,93,95,  96.98
                                                                                                  These waters are assigned the criteria for pol-
                                                                                                   lutants for which the State does not apply
                                                                                                   Table 1 or 2 standards. These criteria are:
                                                                                                       Column  B1—all pollutants
                                                                                                       Column  B2—all pollutants
                                                                                                       Column  D1—all pollutants except #2

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                                 Water and use classification
                                                                                                        Applicable criteria
                                          c/o
                                                                                           These waters are assigned the criteria for pol-
                                                                                             lutants for which  the State does not apply
                                                                                             Table  1 or 2 standards. These criteria are:
                                                                                                Column B1—all pollutants
                                                                                                Column B2—all pollutants
                                                                                                Column D2—all pollutants except #2
All enclosed bays and estuaries that are waters of the United Statesland that the State has either excluded
  or partially excluded from coverage under its Water Quality Control Plan for Inland Surface Waters of
  California, Tables 1 and 2, or its Water Quality Control Plan for Enclosed Bays and Estuaries of California,
  Tables 1 and 2, or has deferred applicability of those tables. (Category (a), (b), and (c) waters described
  on page 6 of Water Quality Control Plan for Inland Surface Waters of California or page 6 of its Water
  Quality Control Plan for Enclosed Bays and Estuaries of California.)
                                                                                           These waters are assigned the criteria for pol-
                                                                                             lutants for which  the State does not apply
                                                                                             Table  1 or 2 standards. These criteria are:
                                                                                                Column B1—all pollutants
                                                                                                Column B2—all pollutants
                                                                                                Column C1—all pollutants
                                                                                                Column C2—all pollutants
                                                                                                Column D2—all pollutants except #2
  ' The fresh water selenium criteria are included for the San Francisco Bay estuary because high levels of bioaccumulation of selenium in the estuary indicate
that the salt water criteria are underprotective for San Francisco Bay.
   (iii) The human health criteria shall be
 applied at the State-adopted  10"* risk lev-
 el.
   (11) Nevada. EPA Region 9.
   (i) All waters assigned the use classifi-
 cations in Chapter 445 of the Nevada Ad-
 ministrative Code (NAC), Nevada Water
 Pollution Control Regulations, which are
                                            referred  to in paragraph  (d)(ll)(ii)  of
                                            this section, are subject to the criteria in
                                            paragraph  (d)(ll)(ii)  of  this  section,
                                            without exception. These criteria amend
                                            the existing State standards contained in
                                            the Nevada Water Pollution Control Reg-
                                            ulations.  More particularly, these criteria
                                            amend or supplement the table of numer-
                                 Water and use classification

Waters that the State has included in NAC 445.1339 where Municipal or domestic supply is a designated
ic standards in  NAC 445.1339  for  the
toxic  pollutants  identified in  paragraph
(d)(l l)(ii) of this section.
   (ii) The  following criteria  from matrix
in paragraph (b)(l) of this section  apply
to  the  waters  defined  in  paragraph
(d)(ll)(i)  of this  section  and  identified
below:

               Applicable criteria
Waters that the State has included in NAC 445.1339 where Municipal or domestic supply is not a designat-
                                                                                            These waters are assigned the criteria in:
                                                                                                 Column B1— pollutant #118
                                                                                                 Column B2—pollutant #118
                                                                                                 Column D1— pollutants #15, 16, 18, 19.
                                                                                                  20, 21, 23,26, 27, 29, 30, 34.37. 38.42.
                                                                                                  43, 55, 58-62. 64. 66.73.74,78, 82.85,
                                                                                                  87-89, 91, 92, 96, 98.  100, 103, 104,
                                                                                                  105, 114, 116, 117, 118
   (iii) The human health criteria shall be
applied  at  the Ifr5  risk  level,  consistent
with State policy. To determine appropri-
ate value for carcinogens, see footnote c in
the criteria matrix in paragraph (b)(l) of
this section.
   (12) Alaska, EPA  Region 10.
   (i) All waters assigned to the following
use classifications in the Alaska Adminis-
trative  Code  (AAC),  Chapter 18  (i.e.,
identified in 18 A AC 70.020) are subject
to the criteria  in paragraph (d)(12)(ii) of
this section, without exception:
70.020.(l) (A) Fresh Water
70.020.(1) (A) Water Supply
                                              (i) Drinking, culinary, and food  pro-
                                                 cessing,
                                              (iii) Aquaculture;
                                            70.020.(1) (B)  Water Recreation
                                              (i) Contact recreation,
                                              (ii) Secondary recreation;
                                            70.020.(1) (C) Growth and  propagation
                                                 of  fish,  shellfish, other aquatic  life,
                                                 and wildlife
                                            70.020.(2) (A)  Marine Water
                                            70.020.(2) (A)  Water Supply
                                              (i) Aquaculture,
                                            70.020.(2) (B)  Water Recreation
                                              (i) contact recreation,
                                              (ii) secondary recreation;
   These waters are assigned the criteria in:
        Column B1—pollutant #118
        Column B2—pollutant #118
        Column D2—all pollutants except #2.

70.020.(2)  (C)  Growth and propagation
     of fish, shellfish, other  aquatic life,
     and wildlife;
70.020.(2)  (D)  Harvesting  for consump-
     tion  of raw mollusks or other raw
     aquatic life.
   (ii) The following criteria from the ma-
trix in paragraph  (b)(l)  of this  section
apply to the  use classifications identified
in paragraph (d)(12)(i) of this section:
  Use classification

OKA),
Applicable criteria

   Column B1— all
   Column
    B2—#10
   Column D1

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  Use classification
(1)(A) in
(2)(A)i, (2)(B)i. and
plicable criteria
#'s 2, 16, 18-21,
23, 26, 27, 29,
30, 32, 37, 38,
42-44, 53, 55,
59-62, 64, 66,
68, 73, 74', 7S,
82, 85, 88, 89,
91-93, 96, 98,
102-105,
107-111,
117-126
Column B1 — all
Column
B2— #10
Column QjL
#'s 2, 14, 16,
18-21, 22, 23,
26, 27, 29, 30,
32, 37, 38,
42-44, 46, 53,
54, 55, 59-62,
64, 66, 68, 73,
74, 78, 82, 85,
88-93, 95, 96,
98, 102-105]
107-111,
115-126
Column B1— all
Column
B2— #10
Column 02
#'s 2, 14, 16,
18-21, 22, 23,
26, 27 29 30
32, 37, 38,
42-44, 46, 53]
54, 55, 59-62,
RA fiC CO 70
O*t, DD, DO, 1 J,
74, 78, 82, 85.
88-93 95 96
98, 102-105!
107-111,
115-126
Column C1 — all
Column
{"•o j#in
\-i£ 	 ff I \J
Column 02
#'s 2, 14, 16,
18-21 22 23
oft 07 oo in
to, £.1 , 
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          APPENDIX B
        Chronological Summary of
      Federal Water Quality Standards          >
          Promulgation Actions              ^
                                       td
WATER QUALITY STANDARDS HANDBOOK

          SECOND EDITION

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                                     Appendix B - Summary of Federal Promulgation Actions
     UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
               OFFICE OF SCIENCE AND TECHNOLOGY
            STANDARDS AND APPLIED SCIENCE DIVISION

                             JANUARY 1993

                   CHRONOLOGICAL SUMMARY OF
               FEDERAL WATER QUALITY STANDARDS
                       PROMULGATION ACTIONS

   STATE         DATE   STATUS REFERENCE      ACTION
 1. Kentucky       12/2/74   Final    39 FR 41709 Established statement in WQS
                                             giving EPA Administrator authority
                                             to grant  a temporary exception to
                                             stream classification and/or criteria
                                             after case-by-case studies. Also,
                                             established statement that streams
                                             not listed in the WQS are
                                             understood to be classified as
                                             Aquatic Life and criteria for this
                                             use to be met.

2*.  Arizona        6/22/76   Final    41 FR 25000 Established nutrient standards for
                                             11 streams.

3.  Nebraska       6/6/78    Final    43 FR 24529 Redesignated eight stream segments
                                             for full body contact recreation and
                                             three for partial body contact
                                             recreation and the protection of fish
                                             and wildlife.

4.  Mississippi      4/30/79   Final    44 FR 25223 Established dissolved oxygen
                                             criterion  for all water uses
                                             recognized by the State.
                                             Established criterion for a daily
                                             average of not less than 5.0 mg/1
                                             with a daily instantaneous minimum
                                             of not less than 4.0 mg/1.
(9/15/93)                                                                 B-l

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Water Quality Standards Handbook - Second Edition
5.  Alabama        11/26/79 Proposed   44 FR 67442 Proposal to reestablish previously
                                                     approved use classifications for
                                                     segments of four navigable
                                                     waterways, Five Mile Creek,
                                                     Opossum Creek, Valley Creek,
                                                     Village Creek, and upgrade the use
                                                     designation of a segment of Village
                                                     Creek from river mile 30 to its
                                                     source.

6.  Alabama        2/14/80    Final     45 FR 9910  Established beneficial stream use
                                                     classification for 16 streams: 8
                                                     were designated for fish and
                                                     wildlife, 7 were upgraded  to a fish
                                                     and wildlife classification,  1 was
                                                     designated as agricultural and
                                                     industrial water supply.  Proposed
                                                     streams classification rulemaking
                                                     for 7 streams withdrawn.

7.  North Carolina  4/1/80     Final     45 FR 21246 Nullified a zero dissolved  oxygen
                                                     standard variance in a segment of
                                                     Welch Creek and reestablished the
                                                     State's previous standard of 5 mg/1
                                                     average, 4 mg/1 minimum, except
                                                     for lower concentrations caused by
                                                     natural swamp conditions.

8.  Ohio           11/28/80   Final     45 FR 79053 (1) Established water use
                                                     designation, (2) establish a DO
                                                     criterion of 5 mg/1 for warmwater
                                                     use, (3) designated 17 streams as
                                                     warmwater habitat,  (4) placed  111
                                                     streams downgraded by Ohio into
                                                     modified warmwater habitat, (5)
                                                     revised certain provisions  relating
                                                     to mixing zones  (principally on
                                                     Lake Erie),  (6) revised low flow
                                                     and other exceptions to  standards,
                                                     (7) amended sampling and
                                                     analytical protocols, and (8)
                                                     withdrew EPA proposal to establish
                                                     a new cyanide criterion.

9.  Kentucky       12/9/80    Final     45 FR 81042 Withdrew the Federal promulgation
                          (withdrawal)               action of 12/2/74 after adoption of
                                                     ppropriate water quality standards
                                                     by the State.


B-2                                                                             (9/15/93)

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                                          Appendix B - Summary of Federal Promulgation Actions
10. North Carolina  11/10/81   Final    46 FR 55520 Withdrew the Federal promulgation
                          (withdrawal)               action of 4/1/80 following State
                                                    adoption of a dissolved oxygen
                                                    criterion consistent with the
                                                    Federally promulgated standard.

11. Ohio            2/16/82   Final    47 FR 29541 Withdrew Federal promulgation of
                          (withdrawal)               11/28/80 because it was based on a
                                                    portion  of the water quality
                                                    standards regulation that has been
                                                    determined to be invalid.

12. Nebraska       7/26/82   Final    47 FR 32128 Withdrew Federal promulgation
                          (withdrawal)               action of 6/6/78 after adoption of
                                                    appropriate water quality standards
                                                    by the State.

13. Alabama        11/26/82  Final    47 FR 53372 Withdrew the Federal promulgation
                          (withdrawal)               action of 2/14/80 following State
                                                    adoption of requirements consistent
                                                    with the Federally promulgated
                                                    standard.

14. Idaho           8/20/85   Proposed 50 FR 33672 Proposal to replace DO criterion
                                                    downstream from dams, partially
                                                    replace Statewide ammonia
                                                    criterion,  replace ammonia criterion
                                                    for Indian Creek, and delete
                                                    categorical exemption of dams from
                                                    Antidegradation Policy.

15. Mississippi      4/4/86    Final    51 FR 11581 Withdrew the Federal promulgation
                          (withdrawal)               of 4/30/79 following State  adoption
                                                    of requirements consistent with the
                                                    Federally promulgated standard.

16. Idaho           7/14/86   Final    51 FR 25372 Withdrew portions of proposed rule
                          (withdrawal)                to replace DO criterion
                                                    downstream from dams and delete
                                                    categorical exemptions of dams
                                                    from antidegradation rule since
                                                    State adopted acceptable  standards
                                                    in both instances.

17. Kentucky       3/20/87   Final    50 FR 9102  Established a chloride criterion of
                                                    600 mg/1 as a 30-day average, not
                                                    to exceed a maximum of 1,200
                                                    mg/1 at any time.


(9/15/93)                                                                           B-3

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Water Quality Standards Handbook - Second Edition
18. Idaho
19*.Coleville
    Indian
    Reservation

20. Kentucky
21*. 12 States
    2 Territories
22. Washington
7/25/88   Final     53 FR 27882  Withdrew portion of proposed rule
      (withdrawal)               which would have established a
                                Statewide ammonia criterion and a
                                site-specific ammonia criterion
                                applicable to lower Indian Creek
                                since State adopted acceptable
                                standards.

7/6/89    Final     54 FR 28622  Established designated uses  and
                                criteria for all surface waters
                                on the Reservation.

4/3/91    Final     56 FR 13592  Withdrew the Federal promulgation
      (withdrawal)               of 3/20/87 after adoption of
                                appropriate WQS by the State.
12/22/92  Final
57 FR 60848  Established numeric water quality
             for toxic pollutants (aquatic life and
             human health).
7/6/93    Final    58 FR 36141  Withdrew, in part, the Federal
      (withdrawal)               Promulgation of 12/22/92 after
                                adoption of appropriate criteria by
                                the State.
* Final federal rule remains in force
          SUMMARY OF FEDERAL PROMULGATION ACTIONS
    Total Number of Proposed or Final Rules

    Final Standards Promulgated

    Withdrawal of Final Standards

    Federal Rules Remaining In Force

    No Action Taken on Proposals or Proposal Withdrawn
                                                   22

                                                   10

                                                   8

                                                   3

                                                   3
 B-4
                                                         (9/15/93)

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          APPENDIX C
           Biological Criteria:
       National Program Guidance            >
           for Surface Waters                hs
                                        »—\
                                        X
                                        n
WATER QUALITY STANDARDS HANDBOOK

           SECOND EDITION

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&EPA
United States       Office at Water           EPA-440/5-90-004
Environmental Protection  Regulations and Standards (WH-585) April 1990
Agency	   Washington. DC 20460	



Biological  Criteria
                  National Program Guidance

                  For Surface Waters
                                                Printed on Recycled Paper

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Biological Criteria
National Program Guidance for
         Surface Waters
          Criteria and Standards Division
       Office of Water Regulations and Standards
        U. S. Environmental Protection Agency
             401 M Street S.W.
           Washington D.C 20460

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                           Contents
Acknowledgments   	iv
Dedication	iv
Definitions	v
Executive Summary	vii

Parti: Program Elements
1.   Introduction	3
    Value of Biological Criteria   	4
    Process for Implementation  	6
    Independent Application of Biological Criteria	7
    How to Use This Document  	7
2.   Legal Authority	9
    Section 303	9
    Section 304   	10
    Potential Applications Under the Act	10
    Potential Applications Under Other Legislation   	10
3.   The Conceptual Framework	13
    Premise for Biological Criteria	13
    Biological Integrity		14
    Biological Criteria	 14
       Narrative Criteria	15
       Numeric Criteria  	16
    Refining Aquatic Life Use Classifications   	17
    Developing and Implementing Biological Criteria	 18

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4.   Integrating Biological Criteria in Surface Water Management   	21
    Implementing Biological Criteria	21
    Biological Criteria in State Programs   	22
    Future Directions	24

Part II:  The Implementation Process
5.   The Reference Condition	27
    Site-specific Reference Condition	28
       The Upstream-Downstream Reference Condition	28
       The Near Field-Far Field Reference Condition   	28
    The Regional Reference Condition  	29
       Paired Watershed Reference Condition   	29
       Ecoregional Reference Condition  	29
6.   The Biological Survey   	33
    Selecting Aquatic Community Components	34
    Biological Survey Design   	35
       Selecting the Metric	35
       Sampling Design	36
7.   Hypothesis Testing: Biological Criteria and the Scientific Method   	37
    Hypothesis Testing	37
    Diagnosis  	38
References	43
Appendix A: Common Questions and Their Answers		45
Appendix B: Table of Contents; Biological Criteria—Technical Reference Guide	  . 49
Appendix C: Table of Contents; Biological Criteria—Development By States	51
Appendix D: Contributors and Reviewers   	53
                                           in

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                               Acknowledgments
   Development of this document required the combined effort of ecologists, biologists, and policy makers from States, EPA
Regions, and EPA Headquarters. Initial efforts relied on the 1988 document Report of the National Workshop on Instream
Biological Monitoring and Criteria that summarizes a 1987 workshop sponsored by the EPA Office of Water Regulations and
Standards, EPA Region V, and EPA Environmental  Research Laboratory-Corvallis. In December 1988, contributing and
reviewing committees were established (see Appendix D). Members provided reference materials and commented on drafts.
Their assistance was most valuable.
   Special recognition goes to the Steering Committee who helped develop document goals and made a significant contribu-
tion toward the final guidance. Members of the Steering Committee include:
                       Robert Hughes, Ph. D.              Chris Yoder
                       Susan Davies                    Wayne Davis
                       John Maxted                     Jimmie Overton
                       James Plafkin, Ph.D.               Dave Courtemanch
                       Phil Larsen, Ph.D.
   Finally, our thanks go to States that recognized the importance of a biological approach in standards and pushed forward
independently to incorporate biological criteria into their programs. Their guidance made this effort possible. Development of
the program guidance document was sponsored by the U.S. EPA Office of Water Regulations and Standards and developed, in
part, through U.S. EPA Contract No. 68-03-3533 to Dynamac Corporation. Thanks to Dr. Mark Southerland for his technical
assistance.
                                      Suzanne K. Macy Many, Ph.D.
                                      Editor
                                       In Memory of

                         James  L.  Plafkin,  Ph.D,
                                                iv

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                              Definitions
       To effectively use biological criteria, a clear understanding of how these criteria are developed and ap-
       plied in a water quality standards framework is necessary. This requires, in part, that users of biological
       criteria start from the same frame of reference. To help form this frame of reference, the following defini-
tions are provided. Please consider them carefully to ensure a consistent interpretation of this document.
Definitions
3 An AQUATIC COMMUNITY is an association of in-
  teracting populations of aquatic organisms in a given
  waterbody or habitat.

0 A BIOLOGICAL ASSESSMENT is an evaluation of
  the biological condition of a waterbody using biologi-
  cal surveys and other direct measurements of resi-
  dent biota in surface waters.

a BIOLOGICAL CRITERIA, or biocriteria, are numeri-
  cal values or narrative expressions that describe the
  reference biological integrity of aquatic communities
  inhabiting waters of a given designated  aquatic life
  use.

Q BIOLOGICAL INTEGRITY is functionally defined as
  the condition of the aquatic community inhabiting
  unimpaired waterbodies of a specified habitat  as
  measured by community structure and function.

a BIOLOGICAL MONITORING is the use of a biologi-
  cal entity  as a detector and its response  as  a
  measure  to  determine environmental  conditions.
  Toxicity tests.and  biological  surveys are common
  biomonitoring methods.

Q A BIOLOGICAL SURVEY, or biosurvey, consists of
  collecting,  processing and analyzing representative
  portions of a resident aquatic community to deter-
  mine the community structure and function.

3 A COMMUNITY COMPONENT is any portion of a
  biological  community. The community component
  may  pertain  to  the taxomonic group (fish, inver-
  tebrates, algae), the taxonomic category (phylum,
  order, family, genus, species), the feeding strategy
  (herbivore, omnivore, carnivore) or organizational
  level (individual, population, community association)
  of a biological entity within the aquatic community.

0 REGIONS OF ECOLOGICAL SIMILARITY describe
  a relatively homogeneous area defined by similarity
  of climate, landform, soil, potential natural vegeta-
  tion, hydrology, or other ecologically relevant vari-
  able. Regions of ecological similarity help define  the
  potential  for designated  use  classifications  of
  specific waterbodies.

Q DESIGNATED  USES are those uses specified in
  water quality standards for each waterbody or seg-
  ment whether or not they are being attained.

Q An IMPACT is a change in the chemical, physical or
  biological quality or condition of a waterbody caused
  by external sources.

Q An  IMPAIRMENT is  a detrimental effect on  the
  biological integrity of a waterbody caused by an  im-
  pact that prevents attainment of the designated use.

G A POPULATION is an aggregate of interbreeding in-
  dividuals  of a biological species within  a specified
  location.

Q A WATER QUALITY ASSESSMENT is an evaluation
  of the condition of a waterbody using biological sur-
  veys,  chemical-specific analyses of pollutants in
  waterbodies, and toxicity tests.

Q An ECOLOGICAL ASSESSMENT is an evaluation
  of the condition of a waterbody using water quality
  and physical habitat assessment methods.

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             Executive  Summary
       The Clean Water Act (Act) directs the U.S. Environmental Protection Agency (EPA) to develop
       programs that will evaluate, restore and maintain the chemical, physical, and biological in-
       tegrity of the Nation's waters. In response to this directive, States and EPA implemented
chemically based water quality programs that successfully  addressed significant water pollution'
problems. However, these programs alone cannot identify or  address all surface water pollution
problems. To create a more comprehensive program, EPA is setting a new priority for the develop-
ment of biological water quality criteria. The initial phase of this program directs State adoption of
narrative biological criteria as part of State water quality standards. This effort will help States and
EPA achieve the objectives of the Clean Water Act set forth in Section 101 and comply with statutory
requirements under Sections 303 and 304. The Water Quality Standards Regulation provides additional
authority for biological criteria development.
   In accordance with priorities established in the FY 1991 Agency Operating Guidance, States are to
adopt narrative biological criteria into State water quality standards during the FY 1991-1993 trien-
nium. To  support this priority, EPA is developing a Policy on  the Use of Biological Assessments and
Criteria in the Water Quality Program and is providing this program guidance document on biological
criteria.
   This document provides guidance for development  and implementation of narrative biological
criteria. Future guidance documents will provide additional technical information to facilitate
development and implementation of narrative and numeric criteria for each of the  surface water
types.
   When implemented, biological criteria will  expand  and improve  water quality  standards
programs, help identify impairment of beneficial uses,  and  help set program priorities. Biological
criteria are valuable  because they directly measure  the condition of the resource at risk, detect
problems that other  methods may miss  or underestimate,  and  provide a systematic process for
measuring progress resulting from the implementation of water quality programs.
                                         vii

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Biological Criteria: National Program Guidance

   Biological criteria require direct measurements of the structure and function of resident aquatic
communities to determine biological integrity and ecological function. They supplement, rather than
replace chemical and toxicological methods. It is EPA's policy that biological survey methods be fully
integrated with toxicity and chemical-specific assessment methods and that chemical-specific criteria,
whole-effluent toxicity evaluations and biological criteria be used as independent evaluations of non-
attainment of designated uses.
   Biological criteria are narrative expressions or numerical values that describe the biological in-
tegrity of aquatic communities inhabiting waters of a given  aquatic life use. They are developed
under the assumptions that surface waters  impacted by anthropogenic activities may contain im-
paired aquatic communities (the greater the impact the greater the expected impairment) and that
surface waters not impacted by  anthropogenic activities are  generally not impaired. Measures of
aquatic community structure and function in unimpaired surface waters functionally define biologi-
cal integrity and form the basis for establishing the biological criteria.
   Narrative biological criteria are definable statements of condition or attainable goals for a given
use designation. They establish a positive statement about aquatic community characteristics ex-
pected to occur within a waterbody (e.g., "Aquatic life shall be as it naturally occurs" or "A natural
variety of aquatic life shall be present and all functional groups well represented"). These criteria can
be developed using existing information. Numeric criteria describe the expected  attainable  com-
munity attributes and establish values based on measures such as species richness, presence or ab-
sence of indicator taxa, and distribution of classes of organisms. To implement narrative criteria and
develop numeric criteria, biota in reference waters must be carefully assessed. These are used as the
reference values to determine if, and to what extent, an impacted surface waterbody is impaired.
   Biological criteria support designated aquatic life use classifications for application in standards.
The designated use determines the benefit or purpose to be derived from the waterbody; the criteria
provide a measure to determine if the use is impaired. Refinement of State water quality standards to
include more detailed language about aquatic life is essential to fully implement a biological criteria
program. Data collected  from biosurveys can identify consistently distinct characteristics among
aquatic communities inhabiting different waters with the same designated use. These biological and
ecological characteristics may be used to define separate categories within a designated use, or
separate one designated use into two or more use classifications.
   To develop values for biological criteria, States should (1) identify unimpaired reference water-
bodies to establish the reference condition and (2) characterize the aquatic communities inhabiting
reference surface waters. Currently, two principal approaches are used to establish reference sites: (1)
the site-specific approach, which may require upstream-downstream or near field-far field evalua-
tions, and (2) the regional approach, which identifies similarities in the physico-chemical charac-
teristics of watersheds that influence aquatic ecology. The basis for choosing reference sites depends
on classifying the habitat type and locating unimpaired (minimally impacted) waters.
                                            viii

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                                                                             Extcuttvf Summary

   Once reference sites are selected, their biological integrity must be evaluated using quantifiable
biological surveys. The success of the survey will depend in part on the careful selection of aquatic
community components (e.g., fish, macroinvertebrates, algae). These components should serve as ef-
fective indicators of high biological integrity, represent a range of pollution tolerances, provide pre-
dictable, repeatable results, and be readily identified by trained State personnel. Well-planned quality
assurance protocols are required to reduce  variability in data collection and to assess the natural
variability inherent in aquatic communities. A quality survey will include multiple community com-
ponents and may be measured using a variety of metrics. Since multiple approaches are available,
factors  to consider  when choosing possible approaches for assessing biological  integrity  are
presented in this document and will be further developed in future technical guidance documents.
   To apply biological criteria  in a water quality standards program, standardized sampling
methods and statistical protocols must be used. These procedures must be sensitive enough to iden-
tify significant differences between  established criteria and tested communities. There are three pos-
sible outcomes from hypothesis testing using these analyses: (1) the use is impaired, (2) the biological
criteria are met,  or (3) the outcome is indeterminate. If the use is impaired, efforts to diagnose the
cause(s) will help determine appropriate action. If the use is not impaired, no action is required based
on these analyses. The outcome will be indeterminate if the study design or evaluation was incom-
plete. In this case, States would need to re-evaluate their protocols.
   If the designated use is impaired, diagnosis is the next step. During diagnostic evaluations three
main impact categories must be considered:  chemical, physical, and biological stress. Two questions
are posed during initial diagnosis: (1) what are obvious potential causes of impairment, and (2) what
possible causes do the biological data suggest?  Obvious potential causes of impairment are often
identified during normal field biological assessments. When an impaired use cannot be easily related
to an obvious cause, the diagnostic process becomes investigative and iterative. Normally the diag-
noses of biological impairments are relatively straightforward; States can use biological criteria to
confirm impairment from a known source of impact.
   There is considerable State interest in integrating biological assessments and criteria in water
quality management programs. A minimum of 20 States now use some form of standardized biologi-
cal assessments to determine the status of biota in State waters. Of these, 15 States are developing
biological assessments for future criteria  development.  Five States use biological criteria to define
aquatic life use classifications and to enforce water quality standards. Several States have established
narrative biological criteria in their  standards. One State has instituted numeric biological criteria.
    Whether a State is just beginning to establish narrative biological criteria or is developing a fully
integrated  biological approach, the programmatic expansion  from source control  to resource
management represents a natural progression in water quality programs. Implementation of biologi-
cal criteria will provide new options for expanding the scope and application of ecological perspec-
tives.
                                             ix

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           Parti
Program Elements

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                                  Chapter  1
                         Introduction
       The principal objectives of the Clean Water
       Act are "to restore and maintain the chemi-
       cal, physical and biological integrity of the
Nation's waters" (Section 101). To achieve these ob-
jectives, EPA, States, the regulated community, and
the public need comprehensive information about
the ecological  integrity of aquatic  environments.
Such information will help us  identify waters requir-
ing special protection and those that will benefit most
from regulatory efforts.
    To meet the objectives of  the Act and to comply
with statutory requirements under Sections 303 and
304, States are to adopt biological criteria in State
standards. The Water Quality Standards Regulation
provides  additional authority  for this effort. In ac-
cordance  with the FY 1991  Agency  Operating
Guidance, States and  qualified Indian tribes are to
adopt narrative biological criteria into State water
quality standards during the FY  1991-1993 trien-
nium. To support this effort,  EPA is developing a
Policy on the Use of  Biological Assessments and
Criteria in the Water Quality Program and providing
this  program  guidance document   on  biological
criteria.
    Like other  water quality  criteria,  biological cri-
teria identify  water quality  impairments,  support
regulatory  controls that  address  water  quality
problems, and assess improvements in water
quality from regulatory efforts. Biological criteria are
numerical values or  narrative expressions that
describe the reference biological integrity of aquatic
communities inhabiting waters of a given desig-
nated aquatic life use. They are developed through
Anthropogenic impacts, including point source
discharges, nonpoint runoff, and habitat degradation
continue to impair the nation's surface waters.
the direct measurement of aquatic community com-
ponents inhabiting unimpaired surface waters.
   Biological criteria  complement  current pro-
grams. Of the three objectives identified in the Act
(chemical, physical, and biological integrity), current
water quality programs focus on direct measures of

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BlotogteMi Crttrts: Nttorml Program GuWanc*
chemical integrity (chemical-specific and whole-ef-
fluent toxicity) and, to some degree,  physical  in-
tegrity through several conventional criteria (e.g.,
pH, turbidity, dissolved oxygen). Implementation of
these programs  has significantly  improved  water
quality.  However,  as we learn more about aquatic
ecosystems  it is  apparent that other sources of
waterbody impairment exist. Biological impairments
from diffuse sources and habitat degradation can be
greater than those caused by point source dischar-
ges (Judy  et a). 1987;  Miller et at. 1989). In Ohio,
evaluation  of instream  biota indicated that 36 per-
cent of impaired  stream segments could not  be
detected using chemical criteria alone (see Fig.  1).
Although  effective  for  their  purpose,  chemical-
specific criteria and whole-effluent toxicity provide
only indirect evaluations and protection of biological
integrity (see Table 1).
    To  effectively  address  our  remaining  water
quality  problems  we need to develop more  in-
tegrated and comprehensive evaluations. Chemical
and physical integrity are necessary, but not suffi-
cient  conditions to  attain  biological integrity, and
only when  chemical, physical, and biological  in-
tegrity are  achieved, is ecological integrity possible
(see Fig. 2). Biological  criteria provide an essential
third element for water quality management and
serve  as  a  natural  progression  in  regulatory
programs.  Incorporating  biological criteria  into a
fully integrated program directly protects the biologi-
cal integrity of surface waters and provides indirect
protection  for chemical and physical integrity (see
Table 2). Chemical-specific criteria,  whole-effluent
toxicity  evaluations,  and biological  criteria,  when
used  together, complement the relative strengths
and weaknesses of each approach.
Figure 1.—Ohio Blosurvey Results Agree with
Instream Chemistry or Reveal Unknown Problems

             Impairment Identification
Chemical Evaluation Indicate
No Impairment: Biosurvey
Show Impairment
Biosurvey Show No
Impairment; Chemical
Evaluation Indicates
Impairment
Chemical Prediction
& Biosurvey Agree
Fig. 1: In an intensive survey, 431 sites in Ohio were assessed
using instream chemistry and biological surveys. In 36% of
the cases, chemical evaluations implied no impairment but
biological survey evaluations showed impairment. In 58% of
the cases the chemical and biological assessments agreed.
Of these, 17% identified waters with no impairment,  41%
identified waters which were considered impaired. (Modified
from Ohio EPA Water Quality Inventory, 1988.)

    Biological  assessments  have  been used in
biomonitoring programs by States for many years.
In this respect,  biological criteria  support earlier
work.  However, implementing biological criteria in
water  quality  standards  provides  a  systematic,
structured,  and objective process  for  making
decisions  about compliance with  water  quality
standards. This distinguishes biological criteria from
earlier use of biological information and increases
the value of biological data in regulatory programs.
Table 1.—Current Water Quality Program Protection of the Three Elements of Ecological Integrity.
ELEMENTS OF ECOLOGICAL
INTEGRITY
Chemical Integrity
Physical Integrity
Biological Integrity
PROGRAM THAT DIRECTLY
PROTECTS
Chemical Specific Criteria (toxics)
Whole Effluent Toxicity (toxics)
Criteria for Conventionals
(pH, DO. turbidity)

PROGRAM THAT INDIRECTLY
PROTECTS


Chemical/Whole Effluent Toxicity
(biotic response in lab)
Table 1: Current programs focus on chemical specific and whole-effluent toxicity evaluations. Both are valuable approaches
for the direct evaluation and protection of chemical integrity. Physical integrity is also directly protected to a limited degree
through criteria for conventional  pollutants. Biological integrity is only indirectly protected under the assumption that by
evaluating toxicity to organisms in laboratory studies, estimates can be made about the toxicity to other organisms inhabiting
ambient waters.

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                                                                                    Chapter 1: Introduction
Table 2.—Water Quality Programs that Incorporate Biological Criteria to Protect Elements of Ecological Integrity.
ELEMENTS OF
ECOLOGICAL INTEGRITY
Chemical Integrity
Physical Integrity
Biological Integrity
DIRECTLY PROTECTS
Chemical Specific Criteria (toxics)
Whole Effluent Toxicity (toxics)
Criteria for conventional (pH, temp.,
DO)
Biocriteria (biotic response in surface
water)
INDIfitCTLY PROTECTS
Biocriteria (identification of
impairment)
Biocntena (habitat evaluation)
Chemical/Whole Effluent Testing
(biotic response in lab)
Table 2: When biological criteria are incorporated into water quality programs the biological integrity of surface waters may
be directly evaluated and protected. Biological criteria also provide additional benefits by requinng an evaluation of physical
integrity and providing a monitoring tool to assess the effectiveness of current chemically based criteria.
Figure 2.—The Elements of Ecological Integrity
Fig. 2: Ecological Integrity  is attainable when chemical,
physical, and biological integrity occur simultaneously.
Value of Biological

Criteria

    Biological criteria provide an effective tool for
addressing remaining  water quality problems by
directing  regulatory  efforts  toward assessing  the
biological resources at risk from chemical, physical
or biological  impacts. A primary strength of biologi-
cal criteria is the detection of water quality problems
that other methods  may miss or  underestimate.
Biological criteria can be used to determine to what
extent current regulations are protecting the use.
    Biological  assessments   provide  integrated
evaluations of water quality. They can identify im-
pairments from contamination of the water column
and sediments from unknown or unregulated chemi-
cals,  non-chemical impacts, and altered  physical
habitat.  Resident  biota  function   as  continual
monitors of environmental  quality,  increasing the
likelihood of detecting the effects of episodic events
(e.g., spills, dumping, treatment plant malfunctions,
nutrient enrichment), toxic nonpoint source pollution
(e.g., agricultural pesticides), cumulative  pollution
(i.e., multiple impacts over time or continuous low-
level stress), or other impacts that periodic chemical
sampling is unlikely to detect. Impacts on the physi-
cal habitat such as sedimentation from stormwater
runoff and  the effects  of physical  or  structural
habitat  alterations  (e.g.,  dredging, filling, chan-
nelization) can also be detected.
    Biological criteria require the direct measure of
resident aquatic community structure and function
to determine biological integrity and ecological func-
tion.  Using these  measures,  impairment  can  be
detected and evaluated without knowing  the im-
pact(s) that may cause the impairment.
    Biological criteria provide  a regulatory frame-
work for addressing water quality problems and
offer additional benefits, including providing:
    • the basis for characterizing high quality
      waters and identifying habitats  and
      community components requiring special
      protection under State anti-degradation
      policies;

    • a framework for deciding 319 actions for best
      control of nonpoint source pollution;

    • an evaluation of surface water impairments
      predicted by chemical analyses, toxicity

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Biological Critorlx National Program Guidance
     testing, and fate and transport modeling (e.g.,
     wasteload allocation);.

    • improvements in water quality standards
     (including refinement of use classifications);

    • a process for demonstrating improvements in
     water quality after implementation of pollution
     controls;

    • additional diagnostic tools.

    The role of biological criteria as a regulatory tool
is  being realized in  some States  (e.g., Arkansas,
Maine, Ohio, North  Carolina,  Vermont).  Biological
assessments and criteria have been useful for
regulatory, resource  protection, and monitoring and
reporting  programs.  By  incorporating  biological
criteria in programs,  States can  improve standards
setting  and  enforcement,  measure  impairments
from permit violations, and refine wasteload alloca-
tion  models.  In addition,  the  location, extent, and
type of biological  impairments  measured in a water-
body provide valuable information needed for iden-
tifying  the cause of impairment and determining
actions required to improve water quality. Biological
assessment and  criteria programs provide  a cost-
effective method for evaluating water quality when a
standardized, systematic approach to study design,
field methods,  and  data  analysis  is established
(Ohio EPA 1988a).
Process  for
Implementation
    The implementation of biological criteria will fol-
low the same process  used for current chemical-
                                 specific and whole-effluent toxicity applications: na-
                                 tional guidance produced by U.S. EPA will support
                                 States working to establish State standards for the
                                 implementation of regulatory programs (see Table
                                 3). Biological criteria differ, however, in the degree
                                 of State  involvement  required.  Because surface
                                 waters vary significantly from region to region, EPA
                                 will provide guidance on acceptable approaches for
                                 biological criteria development rather than specific
                                 criteria with numerical limitations. States are to es-
                                 tablish  assessment  procedures, conduct  field
                                 evaluations, and determine criteria values to imple-
                                 ment biological criteria in State standards and apply
                                 them in regulatory programs.
                                    The degree  of State involvement required  in-
                                 fluences how biological criteria will be implemented.
                                 It  is expected that States  wiH  implement these
                                 criteria in phases.

                                    • Phase I includes the development and adop-
                                       tion of narrative biological  criteria into State
                                       standards  for all  surface  waters  (streams,
                                       rivers, lakes, wetlands, estuaries). Definitions
                                       of terms and  expressions in the narratives
                                       must be included in these standards (see the
                                       Narrative Criteria  Section, Chapter  3). Adop-
                                       tion of narrative  biological criteria  in State
                                       standards  provides the legal and  program-
                                       matic basis  for using  ambient biological sur-
                                       veys and assessments in regulatory actions.

                                    • Phase II includes the development of an im-
                                       plementation plan.  The plan should include
                                       program objectives, study design, research
                                       protocols,  criteria for selecting reference con-
                                       ditions and  community components, quality
                                       assurance  and  quality control  procedures,
Table 3.—Process for Implementation of Water Quality Standards.
CRITERIA
EPA GUIDANCE
STATE IMPLEMENTATION
                                                                               STATE APPLICATION
Chemical Specific
Pollutant specific numeric critena
Narrative Free Forms    Whole effluent toxicity guidance
Biological
Biosurvey minimum requirement
guidance
State Standards
• use designation
• numeric critena
• antidegradation

Water Quality Narrative
• no toxic amounts translator
State Standards
• refined use
• narrative/numeric criteria
• antidegradation
                                                                               Permit limits Monitoring
                                                                               Best Management Practices
                                                                               Wasteload allocation
Permit limits Monitoring
Wasteload allocation
Best Management Practices

Permit conditions Monitoring
Best Management Practices
Wasteload allocation
Table 3: Similar to chemical specific critena and whole effluent toxicity evaluations, EPA is providing guidance to States for
the adoption of biological criteria info State standards to regulate sources of water quality impairment.

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                                                                                Chapter 1:  Introduction
      and training for State personnel. In Phase II,
      States are to develop plans necessary to im-
      plement biological criteria for each surface
      water type.

      Phase III requires full implementation and in-
      tegration of biological criteria in water quality
      standards. This requires using biological sur-
      veys to derive biological criteria for classes of
      surface waters and designated uses. These
      criteria  are then  used  to identify nonattain-
      ment of designated uses and make regulatory
      decisions.
    Narrative biological criteria can  be developed
for all five surface water classifications with little or
no data collection. Application of narrative criteria in
seriously degraded waters is possible in the short
term.  However, because of the diversity of surface
waters and the biota that inhabit these waters, sig-
nificant planning, data collection, and evaluation will
be needed to fully implement the program. Criteria
for  each type  of surface  water are likely  to be
developed at different rates. The  order and rate of
development will depend, in  part, on the  develop-
ment of EPA guidance for specific types of surface
water.  Biological  criteria technical  guidance for
streams will be produced during FY 1991. The ten-
tative order for future technical guidance documents
includes guidance for rivers  (FY  1992), lakes (FY
1993), wetlands (FY 1994) and estuaries (FY 1995).
This order and timeline for guidance does not reflect
the relative importance of these surface waters, but
rather  indicates the relative availability of research
and   the   anticipated   difficulty  of  developing
guidance.
Independent Application

of Biological Criteria

    Biological  criteria  supplement,  but  do not
replace, chemical and lexicological methods. Water
chemistry methods are necessary to predict risks
(particularly to human health and wildlife), and to
diagnose, model,  and regulate important water
quality problems. Because  biological criteria are
able to detect different types of water quality impair-
ments and, in particular, have different levels of sen-
sitivity  for detecting  certain types of impairment
compared to lexicological methods, they are not
used in lieu of, or in conflict with, current regulatory
efforts.
    As with all criteria, certain limitations to biologi-
cal criteria make independent application essential.
Study design  and use  influences how sensitive
biological criteria are for detecting community im-
pairment. Several factors influence sensitivity:  (1)
State decisions about what is significantly different
between reference and test communities, (2) sludy
design, which may include community components
lhat are not sensitive to the impact causing impair-
ment, (3) high natural variability that makes it dif-
ficult  to detect real differences, and  (4) types of
impacts that  may  be  detectable sooner by other
melhods (e.g., chemical criteria may provide earlier
indications of  impairment from a  bioaccumulative
chemical  because aquatic communities require ex-
posure over time to incur the full effect).
    Since each type of  criteria (biological criteria,
chemical-specific criteria, or  whole-effluent toxicity
evaluations)  has different  sensitivities  and pur-
poses, a criterion may fail to detect real impairments
when used alone. As a result, these methods should
be used together in an integrated water quality as-
sessment, each providing an independent evalua-
tion of nonattainment  of a designated use.  If any
one type of criteria indicates  impairment of the sur-
face water, regulatory action can  be  taken to im-
prove water quality. However, no one type of criteria
can  be  used  to confirm  attainment of a use if
another form  of criteria indicates nonattainment
(see Hypothesis Testing: Biological Criteria and the
Scientific Method,  Chapter 7). When these three
methods are used together, they provide a powerful,
integrated, and effective foundation for waterbody
management and regulations.
How to  Use this

Document

    The purpose of this document is to provide EPA
Regions, States and others  with the  conceptual
framework  and  assistance necessary  to develop
and implement  narrative  and numeric biological
criteria and to promote national consistency in ap-
plication. There are two main parts of the document.
Part One (Chapters 1, 2, 3, and 4) includes the es-
sential concepts about what biological  criteria are

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              NtttonH Prognm GuH*
and how they are used in regulatory programs. Part
Two (Chapters 5, 6, and 7) provides an overview of
the process that  is essential for  implementing  a
State biological criteria program. Specific chapters
include the following:


Parti:  PROGRAM ELEMENTS

  Q Chapter 2, Legal Authority, reviews the legal
    basis for biological criteria under the Clean
    Water Act and includes possible applications
    under the Act and other legislation.

  Q Chapter 3, Conceptual Framework,
    discusses the essential program elements for
    biological criteria, including what they are and
    how they are developed and used within a
    regulatory program. The development of
    narrative biological criteria is discussed in this
    chapter.

  Q Chapter 4, Integration, discusses the use of
    biological criteria in regulatory programs.


Part II:  THE IMPLEMENTATION PROCESS

  a Chapter 5, The Reference Condition,
    provides a discussion on alternative forms of
    reference conditions that may be developed by
    a State based on circumstances and needs.

  a Chapter 6, The Biological Survey, provides
    some detail on the elements of a quality
    biological survey.

  a Chapter 7, Hypothesis Testing: Biological
    Criteria and the Scientific Method, discusses
    how biological surveys are used to make
    regulatory and diagnostic decisions.

  Q Appendix A includes commonly asked
    questions and their answers about biological
    criteria.
    Two additional documents are planned in the
near term to supplement this program guidance
document.

    1.  "Biological  Criteria   Technical  Reference
       Guide" will contain a cross reference of tech-
       nical  papers on available approaches and
       methods  for developing  biological criteria
       (see tentative table of contents in Appendix
       B),

    2.  "Biological Criteria Development by States?
       will provide a summary of different mecha-
       nisms several States have used to implement
       and apply biological criteria in water quality
       programs (see tentative outline in Appendix
       C).

    Both  documents are planned for FY 1991. As
previously discussed, over the next triennium tech-
nical guidance for specific systems (e.g.,  streams,
wetlands) will be developed to provide guidance on
acceptable biological assessment procedures to fur-
ther support State implementation of  comprehen-
sive programs.
    This biological criteria program guidance docu-
ment supports development and implementation  of
biological criteria by providing  guidance to States
working to  comply with  requirements under the
Clean Water Act and the Water Quality Standards
Regulation. This guidance is not regulatory.

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                                 Chapter  2
                     Legal  Authority
       The Clean Water Act (Federal Water Pollution
       Control  Act of 1972, Clean Water Act of
       1977, and the Water Quality Act of 1987)
mandates State development of criteria based on
biological assessments of natural ecosystems.
   The general authority for biological  criteria
comes from Section 101 (a) of the Act which estab-
lishes as the objective of the Act the restoration and
maintenance of the chemical, physical, and biologi-
cal integrity of the Nation's waters. To meet this ob-
jective, water quality criteria must  include criteria to
protect biological integrity. Section  101(a)(2)  in-
cludes the  interim water quality goal for the protec-
tion and propagation of fish, shellfish, and  wildlife.
Propagation includes the  full range of biological
conditions  necessary  to  support  reproducing
populations of all forms of aquatic life and other life
that depend on aquatic systems. Sections 303 and
304 provide specific directives for the development
of biological criteria.
Balancing the legal authority for biological criteria.
Section 303

    Under Section 303(c) of the Act, States are re-
quired to adopt protective water quality standards
that consist of uses,  criteria, and antidegradation.
States are to review  these standards every  three
years and to revise them as needed.
    Section 303 (c) (2) (A)  requires the adoption of
water quality standards that"... serve the purposes
of the  Act," as  given in Section  101. Section
303(c)(2) (B), enacted in  1987, requires States to
adopt numeric criteria for toxic pollutants for which
EPA has published 304(a)(1) criteria. The section
further requires that, where numeric 304(a) criteria
are not available, States should adopt criteria based
on biological assessment and monitoring methods,
consistent with information nublished by EPA under
304(a)(8).
   These specific directives do not serve to restrict
the use of biological criteria in other settings where
they may be  helpful. Accordingly, this guidance
document  provides  assistance  in  implementing
various sections of the Act, not just 303(c)(2) (B).

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Stotogfca/ CWfcrfr Nation! Program Guidance
Section 304

   Section 304(a) directs EPA to develop and
publish water quality criteria and  information on
methods for measuring water quality  and estab-
lishing water quality criteria for toxic pollutants on
bases other than pollutant-by-pollutant,  including
biological  monitoring and  assessment  methods
which assess:

   • the effects of pollutants on aquatic community
     components ("... plankton, fish, shellfish,
     wildlife, plant life...") and community
     attributes ("... biological community diversity,
     productivity, and stability ..."); in any body of
     water and;

   • factors necessary"... to restore and
     maintain the chemical, physical, and
     biological integrity of all  navigable waters ..."
     for". .. the protection of shellfish, fish, and
     wildlife for classes and categories of receiving
     waters.. ."
Potential  Applications

Under the Act

    Development and use of biological criteria will
help States to meet other requirements of the Act,
including:

  a setting planning and management priorities for
     waterbodies most in need of controls
     [Sec. 303(d)];

  a determining impacts from nonpoint sources
     [i.e., Section 304(f) "(1) guidelines for
     identifying and evaluating the nature and
     extent of nonpoint sources of pollutants, and
     (2) processes, procedures, and methods to
     control pollution..."].

  a biennial reports on the extent to which waters
     support balanced biological communities
     [Sec. 305(b)];

  a assessment of lake trophic status and trends
     [Sec. 314];
  Q lists of waters that cannot attain designated
    uses without nonpoint source controls
    [Sec. 319];

  a development of management plans and
    conducting monitoring in estuaries of national
    significance [Sec. 320];

  Q issuing permits for ocean discharges and
    monitoring ecological effects [Sec. 403(c) and
    301 (h) (3)];

  a determination of acceptable sites for disposal
    of dredge and fill material [Sec. 404];
Potential Applications

Under Other Legislation

   Several legislative acts require an assessment
of risk to the environment (including resident aquatic
communities) to determine the need for regulatory
action. Biological criteria can be used in this context
to support EPA assessments under:

  a Toxic Substances Control Act (TSCA) of 1976

  a Resource Conservation and Recovery Act
    (RCRA),

  a Comprehensive Environmental Response,
    Compensation and Liability Act of 1980
    (CERCLA),

  a Superfund Amendments and Reauthorization
    Act of 1986 (SARA),

  a Federal Insecticide, Fungicide, and
    Rodenticide Act (FIFRA);

  Q National Environmental Policy Act (NEPA);

  a Federal Lands Policy and Management Act
    (FLPMA).

  a The Fish and Wildlife Conservation Act of 1980

  a Marine Protection, Research, and Sanctuaries
    Act

  a Coastal Zone Management Act
                                              10

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                                                                              Chapter 2: Lagal Authority
  3  Wild and Scenic Rivers Act

  3  Fish and Wildlife Coordination Act, as
     Amended in 1965

   A summary of the applicability of these Acts for
assessing ecological impairments may be found in
Risk Assessment Guidance for Superfund-Environ-
mentai Evaluation Manual (Interim Final) 1989.
   Other federal  and State agencies  can  also
benefit from using biological criteria to evaluate the
biological  integrity of  surface  waters  within their
jurisdiction and to the effects of specific practices on
surface water quality. Agencies that could benefit in-
clude:

  3  Department of the Interior (U.S. Fish and
     Wildlife Service, U.S. Geological Survey,
     Bureau of Mines, and Bureau of Reclamation,
     Bureau of Indian Affairs, Bureau of Land
     Management, and National Park Service),

  3  Department of Commerce (National Oceanic
     and Atmospheric Administration, National
     Marine Fisheries Service),

  3  Department of Transportation (Federal
     Highway Administration)

  3  Department of Agriculture (U.S. Forest
     Service, Soil Conservation Service)

  3  Department of Defense,

  3  Department of Energy,

  3  Army Corps of Engineers,

  3  Tennessee Valley Authority.
                                                11

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                              Chapter  3
   The  Conceptual  Framework
      Biological integrity and the determination of
      use impairment through assessment of am-
      bient biological communities form the foun-
dation  for biological  criteria development. The
effectiveness  of a biological criteria program will
depend on the development of quality criteria, the
refinement of use  classes  to  support narrative
criteria, and careful application of scientific prin-
ciples.
Premise for Biological

Criteria

   Biological criteria are based on the premise that
the structure and function of an aquatic biological
community within a specific habitat provide critical
information about the quality of surface waters. Ex-
isting aquatic communities in pristine environments
not  subject to anthropogenic impact exemplify
biological integrity and serve as the  best possible
goal for water quality.  Although pristine environ-
ments are  virtually non-existent  (even  remote
waters are impacted by air pollution), minimally im-
pacted waters exist. Measures of the structure and
function of  aquatic communities inhabiting unim-
paired (minimally impacted)  waters provide the
basis for establishing a reference condition that may
be compared to the condition of impacted surface
waters to determine impairment.
   Based on this premise, biological criteria are
developed under the assumptions that:  (1) surface
waters subject to  anthropogenic disturbance may
contain impaired  populations or  communities of
aquatic organisms—the greater the anthropogenic
Aquatic communities assessed in unimpaired
waterbodies (top) provide a reference for evaluating
impairments in the same or similar waterbodies suffering
from increasing anthropogenic impacts (bottom).
                                        13

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SfetogfctfCMMric NttonHPmgnmQuUtt
disturbance, the greater the likelihood  and mag-
nitude  of impairment; and  (2) surface waters not
subject to anthropogenic disturbance generally con-
tain  unimpaired (natural)  populations  and com-
munities of aquatic organisms exhibiting biological
integrity.
the basis for establishing water  quality goals  for
those waters. When  tied to the development of
biological criteria, the realities of limitations  on
biological integrity can be considered  and incor-
porated  into a  progressive  program  to  improve
water quality.
Biological Integrity

    The expression "biological integrity* is used in
the Clean Water Act to define the Nation's objec-
tives for water quality. According to Webster's New
World Dictionary (1966), integrity is, "the quality or
state of being  complete; unimpaired." Biological in-
tegrity has been defined as "the ability of an aquatic
ecosystem to support and maintain a balanced, in-
tegrated, adaptive community of organisms having
a species composition, diversity, and functional or-
ganization comparable to that of the natural habitats
within a region" (Karr and Dudley 1981). For the pur-
poses of biological criteria, these concepts are com-
bined  to  develop  a  functional  definition  for
evaluating  biological  integrity in  water  quality
programs. Thus, biological  integrity is functionally
defined as:

     the condition of the aquatic community
     inhabiting the unimpaired waterbodies
     of a specified habitat as measured by
     community structure and function.

    It will often be difficult to find unimpaired waters
to define biological integrity and establish the refer-
ence condition. However, the structure and function
of aquatic communities of high quality waters can be
approximated  in several  ways. One is  to charac-
terize aquatic communities  in the most protected
waters representative of the regions where  such
sites exist. In area* where  few or  no unimpaired
sites are available, characterization  of least im-
paired systems approximates unimpaired systems.
Concurrent analysis  of historical  records should
supplement descriptions of the condition of least im-
paired systems.  For some systems, such as lakes,
evaluating  paleoecological information (the record
stored in sediment profiles) can provide a measure
of less disturbed conditions.
    Surface waters, when inhabited by aquatic com-
munities, are  exhibiting a degree of biological in-
tegrity.   However,  the  best  representation  of
biological integrity for a surface water should form
Biological Criteria

    Biological criteria are narrative expressions or
numerical values that describe the  biological  in-
tegrity of aquatic communities inhabiting waters of a
given designated aquatic life use. While  biological
integrity  describes  the  ultimate goal  for  water
quality, biological criteria are based on aquatic com-
munity structure and function for waters within a
variety of designated uses. Designated aquatic  life
uses serve as general statements of attained or at-
tainable uses of State waters. Once established for
a designated use, biological criteria are quantifiable
values used to determine whether a use is impaired,
and if so, the level of impairment. This is done by
specifying what aquatic community  structure and
function should  exist in waters of a given designated
use, and then comparing this condition with the con-
dition of a  site under evaluation. If the existing
aquatic   community  measures  fail  to  meet the
criteria, the use is considered impaired.
    Since biological  surveys  used  for  biological
criteria  are capable of detecting  water quality
problems (use  impairments)  that  may not  be
detected by chemical or toxicity testing, violation of
biological criteria is sufficient cause for States to in-
itiate regulatory action. Corroborating chemical and
toxicity testing  data are not required (though they
may be desirable) as supporting evidence to sustain
a determination of use impairment. However, a find-
ing that biological criteria fail to indicate use impair-
ment does  not  mean  the use is  automatically
attained. Other evidence, such as violation of physi-
cal or chemical  criteria, or results from toxicity tests,
can also be used to identify impairment. Alternative
forms of criteria provide independent assessments
of nonattainment.
    As stated above, biological criteria may be nar-
rative statements or numerical values. States can
establish general narrative biological criteria early in
program development without conducting biological
assessments. Once established in State standards,
narrative biological  criteria form the  legal  and
                                                 14

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                                                                        Chapters: The Conceptual Framework
programmatic basis for expanding biological as-
sessment and biosurvey programs needed to imple-
ment  narrative  criteria   and  develop  numeric
biological  criteria  Narrative  biological   criteria
should become part of State regulations and stand-
ards.
Narrative Criteria

    Narrative  biological criteria are general state-
ments of attainable or attained conditions of biologi-
cal integrity  and  water quality for a given  use
designation.  Although  similar  to the  "free from"
chemical water quality  criteria,  narrative biological
criteria  establish  a positive statement  about what
should occur within a water body. Narrative criteria
can take a number of forms but they must contain
several attributes to support the goals of the Clean
Water Act to provide for the protection and propaga-
tion of fish, shellfish, and wildlife. Thus, narrative
criteria  should  include specific  language about
aquatic community  characteristics  that  (1)  must
exist in a waterbody to meet a particular designated
aquatic life use, and (2) are quantifiable. They must
be written to protect the use. Supporting statements
for the criteria should  promote  water quality  to
protect the most natural community possible for the
designated use. Mechanisms should be established
in the standard to  address potentially conflicting
multiple  uses.  Narratives  should  be  written  to
                                      protect  the most sensitive  use and support an-
                                      tidegradation.
                                          Several States currently use narrative  criteria.
                                      In Maine, for example, narrative criteria were estab-
                                      lished for four classes of water quality for streams
                                      and rivers (see Table 4). The classifications were
                                      based on the range of goals in the Act from  "no dis-
                                      charge"  to "protection  and  propagation  of fish,
                                      shellfish,  and wildlife*  (Courtemanch and  Oavies
                                      1987). Maine separated its "high quality water" into
                                      two categories, one that reflects the highest goal of
                                      the  Act  (no discharge, Class  AA)  and one that
                                      reflects high integrity but is minimally impacted by
                                      human  activity  (Class  A).  The  statement "The
                                      aquatic life ... shall be as naturally occurs" is a nar-
                                      rative biological criterion for both Class AA and A
                                      waters. Waters in Class B meet the use when the
                                      life stages of all indigenous aquatic species are sup-
                                      ported and no detrimental changes  occur  in com-
                                      munity  composition  (Maine DEP   1986).  These
                                      criteria  directly support refined designated aquatic
                                      life uses (see Section D, Refining Aquatic Life Use
                                      Classifications).
                                          These narrative criteria are effective only if, as
                                      Maine  has  done, simple  phrases  such  as "as
                                      naturally occurs" and "nondetrimental" are clearly
                                      operationally  defined.  Rules for  sampling proce-
                                      dures and data analysis and interpretation should
                                      become  part  of  the  regulation  or  supporting
                                      documentation. Maine  was  able to  develop these
                                      criteria  and their supporting statements using avail-
Table 4.—Aquatic Life Classification Scheme for Maine's Rivers and Streams.
RIVERS AND
STREAMS
MANAGEMENT PERSPECTIVE
LEVEL OF BIOLOGICAL INTEGRITY
Class AA       High quality water for preservation of
               recreational and ecological interests. No
               discharges of any kind permitted. No
               impoundment permitted.
Class A        High quality water with limited human
               interference. Discharges restricted to noncontact
               process water or highly treated wastewater of
               quality equal to or better than the receiving
               water. Impoundment permitted.
Class B        Good quality water. Discharges of well treated
               effluents with ample dilution permitted.
Class C        Lowest quality water. Requirements consistent
               with interim goals of the federal Water Quality
               Law (fishable and swimmable).
                                              Aquatic life shall be as naturally occurs.
                                              Aquatic life shall be as naturally occurs.
                                              Ambient water quality sufficient to support life
                                              stages of all indigenous aquatic species. Only
                                              nondetnmental changes in community
                                              composition may occur.
                                              Ambient water quality sufficient to support the
                                              life stages of all indigenous fish species
                                              Changes in species composition may occur but
                                              structure and function of the aquatic community
                                              must be maintained.
                                                  15

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              NtUonal Pngnm Gukitn
able data from water quality programs. To imple-
ment the criteria, aquatic life inhabiting unimpaired
waters must be measured to  quantify the criteria
statement.
    Narrative criteria can take  more specific forms
than illustrated  in the Maine  example.  Narrative
criteria may include specific classes and species of
organisms that will occur in waters for a given desig-
nated use. To develop these narratives, field evalua-
tions of  reference conditions are necessary to
identify biological community  attributes that differ
significantly between designated uses. For example
in  the Arkansas use class Typical Gull Coastal
Ecoregion (i.e., South Central  Plains)  the narrative
criterion reads:

     "Streams supporting diverse
     communities of indigenous or adapted
     species offish and other forms of
     aquatic life. Fish communities are
     characterized by a limited proportion of
     sensitive species; sunfishes are
     distinctly dominant, followed by darters
     and minnows. The community may be
     generally characterized by the following
     fishes: Key Species—Redfin shiner,
     Spotted sucker, Yellow bullhead, Flier,
     Slough darter, Grass pickerel; Indicator
     Species—Pirate perch, Warmouth,
     Spotted sunfish, Dusky darter, Creek
     chubsucker, Banded pygmy sunfish
     (Arkansas DPCE 1988).

    In Connecticut,  current designated  uses  are
supported by narratives  in the standard. For ex-
ample, under Surface Water Classifications, Inland
Surface Waters Class AA, the Designated Use is:
"Existing  or proposed  drinking water supply;  fish
and wildlife habitat; recreational use; agricultural, in-
dustrial supply, and other purposes (recreation uses
may be restricted)."
    The supporting narratives include:

     Benthic invertebrates which inhabit lotic
     waters: A  wide variety of
     macroinvertebrate taxa should normally
     be present and all functional groups
     should normally be well represented...
     Water quality shall be sufficient to
     sustain a diverse macroinvertebrate
     community of indigenous species. Taxa
     within the Orders Plecoptera
     (stoneflies), Ephemeroptera (mayflies),
     Coleoptera (beetles), Tricoptera
     (caddisflies) should be well represented
     (Connecticut DEP 1987).

    For these narratives to be effective in a biologi-
cal criteria program  expressions such as "a wide
variety" and "functional groups should normally be
well represented" require  quantifiable definitions
that become part of the standard or supporting
docum    -.;;on. Many States  may find such narra-
tives in .  -ir standards already. If so, States should
evaluate  current language to determine if it meets
the requirements of quantifiable narrative criteria
that support refined aquatic life uses.
    Narrative biological criteria  are similar  to the
traditional narrative "free froms" by providing the
legal basis for standards applications. A sixth "free
from" could be incorporated into standards to help
support narrative biological criteria such  as "free
from activities that would  impair the aquatic com-
munity as it naturally occurs." Narrative biological
criteria can be used immediately to address obvious
existing problems.
Numeric Criteria

    Numerical  indices  that  serve  as  biological
criteria should  describe expected  attainable com-
munity attributes for different designated uses. It is
important to note that full implementation of narra-
tive criteria will require similar data as that  needed
for developing numeric criteria. At this time, States
may or may not choose to establish numeric criteria
but may find it an effective tool for regulatory use.
    To derive a numeric criterion, an aquatic com-
munity's structure and function is measured at refer-
ence  sites  and  set  as  a  reference condition.
Examples of relative measures include similarity in-
dices,  coefficients of community  loss, and com-
parisons of lists  of  dominant taxa. Measures  of
existing community structure such as species rich-
ness, presence or absence of indicator taxa, and
distribution of trophic feeding groups are useful for
establishing the normal range of community com-
ponents to be expected in unimpaired systems. For
example,  Ohio  uses  criteria for  the  warmwater
habitat use class based on multiple measures in dif-
ferent  reference sites  within  the same ecoregion.
Criteria are  set as the 25th percentile of all biologi-
cal index scores recorded at established reference
                                                 16

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                                                                     Chapters:  The Conceptual Framework
sites within the ecoregion. Exceptional warmwater
habitat index criteria are set at the 75th  percentile
(Ohio EPA 1988a). Applications such as this require
an extensive data base and multiple reference sites
for each criteria value.
    To develop numeric biological criteria, careful
assessments of biota in  reference  sites must be
conducted  (Hughes  et   al.  1986).  There  are
numerous ways to assess community structure and
function  in  surface  waters.  No single  index or
measure is universally recognized as free from bias.
It is important to evaluate the strengths and weak-
nesses of different assessment approaches. A multi-
metric approach  that incorporates information on
species richness, trophic composition, abundance
or  biomass,  and organism  condition is recom-
mended. Evaluations that measure multiple com-
ponents  of  communities are also  recommended
because they  tend to be  more  reliable  (e.g.,
measures of fish and macroinvertebrates combined
will provide more information than measures of fish
communities  alone). The  weaknesses  of  one
measure or index can often be compensated by
combining it with the strengths of other community
measurements.
    The particular indices used to develop numeric
criteria  depend on  the  type of surface waters
(streams, rivers, lakes, Great Lakes,  estuaries, wet-
lands, and nearshore marine) to which they must be
applied.  In general,  community-level indices such
as  the Index of Biotic Integrity developed for mid-
western streams  (Karr et al. 1986) are more easily
interpreted and less  variable than fluctuating num-
bers such as population size. Future EPA technical
guidance documents will include evaluations of the
effectiveness of different biological survey and as-
sessment approaches for measuring the biological
integrity  of  surface water  types and  provide
guidance on acceptable approaches for biological
criteria development.
Refining Aquatic Life Use

Classifications

    State standards  consist  of  (1)  designated
aquatic life uses, (2) criteria sufficient to protect the
designated  and  existing use,  and  (3)  an  an-
tidegradation  clause.  Biological  criteria  support
designated aquatic life  use  classifications for ap-
plication  in State standards. Each State develops its
own designated use classification system based on
the generic uses  cited in the Act (e.g., protection
and  propagation  of fish,  shellfish, and  wildlife).
Designated uses  are intentionally general.  How-
ever, States may develop subcategories within use
designations  to refine and clarify the use class.
Clarification of the use class is particularly helpful
when a variety of  surface waters with distinct char-
acteristics fit within the same use class, or do not fit
well into any  category. Determination of nonattain-
ment in these waters may be difficult and open to al-
ternative  interpretations.  If a  determination  is  in
dispute, regulatory  actions will be difficult to ac-
complish. Emphasizing aquatic community structure
within the designated use focuses the evaluation of
attainment/nonattainment on the resource of con-
cern under the Act.
    Flexibility inherent in the  State  process  for
designating uses  allows the development of sub-
categories  of  uses   within   the Act's   general
categories. For example, subcategories of aquatic
life uses may be on the basis of attainable habitat
(e.g.,  cold  versus warmwater  habitat); innate dif-
ferences in community structure and function, (e.g.,
high versus low species richness or productivity); or
fundamental  differences  in important community
components  (e.g.,  warmwater fish  communities
dominated  by bass versus catfish). Special uses
may also be  designated to protect particularly uni-
que, sensitive,  or valuable aquatic species,  com-
munities, or habitats.
    Refinement  of  use   classes  can  be  ac-
complished within current State use classification
structures. Data collected from biosurveys as part of
a developing  biocriteria program may reveal unique
and  consistent differences among aquatic  com-
munities inhabiting  different waters with the  same
designated use.  Measurable  biological attributes
could then be used to separate one class into two or
more classes. The result is a  refined aquatic life
use. For example,  in Arkansas the beneficial use
Fisheries "provides for the protection and  propaga-
tion of fish, shellfish, and other forms of aquatic life"
(Arkansas DPCE  1988). This use is subdivided into
Trout, Lakes  and  Reservoirs, and Streams. Recog-
nizing that stream characteristics across regions of
the State differed  ecologically, the  State further sub-
divided the stream designated  uses into eight addi-
tional uses based on  regional characteristics (e.g
Springwater-influenced  Gulf   Coastal  Ecoregion,
Ouachita  Mountains Ecoregion).  Within this clas-
sification system,  it was relatively straightforward for
                                                17

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Stotogfca/ Crftirfr NtUontl Pngnm Gutii
Arkansas to establish detailed narrative  biological
criteria that list aquatic community components ex-
pected in each  ecoregion (see Narrative Criteria
section).  These narrative criteria can then be used
to establish whether the use is impaired.
    States can refine very general designated uses
such as  high, medium, and low quality to specific
categories that include measurable ecological char-
acteristics. In Maine, for example, Class AA waters
are defined as "the highest classification  and shall
be applied to waters which are outstanding natural
resources and which should be preserved because
of their ecological, social, scenic, or recreational im-
portance." The designated use includes 'Class AA
waters shall be of such quality that they are suitable
... as habitat for fish and other aquatic life. The
habitat shall be  characterized as free flowing and
natural."  This  use supports development of narra-
tive criteria based on  biological characteristics  of
aquatic communities  (Maine DEP  1986; see the
Narrative Criteria section).
    Biological  criteria that include lists of dominant
or typical species expected to live in the surface
water are particularly effective. Descriptions of im-
paired conditions are more difficult to  interpret.
However, biological criteria may contain statements
concerning which species dominate disturbed sites,
as well as those species expected at minimally im-
pacted sites.
    Most  States collect  biological data in  current
programs. Refining aquatic  life use classifications
and incorporating biological criteria into standards
will enable States to evaluate these data more ef-
fectively.
Developing and

Implementing Biological

Criteria

    Biological criteria development and implemen-
tation in standards require an understanding of the
selection and evaluation of reference sites, meas-
urement of aquatic community structure and func-
tion, and  hypothesis testing  under the scientific
method. The developmental process is important for
State water quality managers and their staff to un-
derstand to promote effective planning  for resource
and staff needs. This major program element deser-
ves careful consideration and has been separated
out in Part II by chapter for each developmental step
as noted below. Additional guidance will be provided
in future technical guidance documents.
   The developmental process is illustrated in Fig-
ure 3. The first step is establishing narrative criteria
in standards. However, to support these narratives,
standardized protocols need  to  be developed  to
quanitify the  narratives for  criteria implementation.
They should  include data  collection  procedures,
selection of reference sites, quality assurance and
quality control procedures,  hypothesis testing, and
statistical  protocols. Pilot studies should be  con-
ducted  using these standard protocols to ensure
they  meet the  needs  of  the program,  test  the
hypotheses, and provide effective measures of the
biological integrity of surface waters in the State.

Figure 3.—Process for the Development and
Implementation of Biological Criteria
            Develop Standard Protocols
             (Test protocol sensitivity)
        Identify and Conduct Biosurveys at
            Unimpaired Reference Sites
            Establish Biological Criteria
                       *
       Conduct Biosurveys at Impacted Sites
             (Determine impairment)
                                                                                  Not Impaired
   Impaired Condition

           t
   Diagnose Cause of
       Impairment
 No Action Required
Continued Monitoring
   Recommended
    Implement Control
Fig. 3: Implementation of biological criteria requires the in-
itial selection of reference sites and characterization of resi-
dent aquatic communities inhabiting those sites to establish
the reference condition and biological criteria. After criteria
development, impacted sites are evaluated using the same
biosurvey procedures to assess resident biota. If impairment
is found, diagnosis of cause will lead to the implementation
of  a control. Continued monitoring should accompany con-
trol implementation to determine the effectiveness of  in-
tervention. Monitoring is also recommended where no im-
pairment is found to ensure that the surface water maintains
or  improves in quality.
                                                 18

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                                                                      Chapters: The Conceptual Framework
    The next step is establishing the reference con-
dition for the surface water being tested. This refer-
ence  may  be site  specific  or regional  but must
establish the unimpaired  baseline for  comparison
(see Chapter 5, The  Reference Condition). Once
reference sites are selected, the biological integrity
of the site must be evaluated using carefully chosen
biological surveys. A quality biological survey will in-
clude multiple community  components and  may be
measured using a variety of metrics (see Chapter 6,
The Biological Survey). Establishing the reference
condition and conducting  biological surveys at the
reference locations provide the necessary informa-
tion for establishing the biological criteria.
    To apply biological criteria, impacted  surface
waters with comparable habitat characteristics are
evaluated using the same procedures as those used
to establish the criteria. The  biological survey must
support standardized sampling methods and statis-
tical protocols that are sensitive enough to  identify
biologically  relevant  differences between estab-
lished criteria and the community under evaluation.
Resulting data  are compared through hypothesis
testing to determine  impairment (see Chapter 7,
Hypothesis Testing).
    When water quality impairments are detected
using biological criteria, they can only be applied in
a regulatory setting if the cause for impairment can
be identified. Diagnosis is iterative and investigative
(see Chapter 7, Diagnosis). States must then deter-
mine  appropriate actions to  implement controls.
Monitoring  should remain a part of the biological
criteria program whether impairments are found or
not. If an impairment  exists, monitoring provides a
mechanism to determine if the control  effort (inter-
vention)  is resulting in improved water  quality. If
there  is no  impairment,  monitoring  ensures the
water quality is maintained and documents  any im-
provements. When  improvements  in water quality
are detected through  monitoring programs  two ac-
tions are recommended. When reference condition
waters improve, biological criteria values should be
recalculated to reflect this higher level of integrity.
When impaired surface  waters improve, states
should reclassify  those waters to reflect a refined
designated use with a higher level of biological in-
tegrity. This provides  a mechanism for progressive
water quality improvement.
                                                 19

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                           Chapter 4
         Integrating  Biological
   Criteria  Into  Surface  Water
                     Management
   Integrating biological criteria into existing water
   quality programs will help to assess use attain-
   ment/nonattainment,  improve  problem  dis-
covery in specific waterbodies, and characterize
overall water resource condition within  a region.
Ideally, biological criteria function in an iterative man-
ner. New biosurvey information can be used to refine
use classes.  Refined use  classes will help support
criteria development and improve the value of data
collected in biosurveys.
Implementing Biological

Criteria

   As biological survey data are collected, these
data will  increasingly  support  current use  of
biomonitoring  data  to  identify  water quality
problems,  assess their severity, and set planning
and management priorities for remediation. Monitor-
ing data and biological criteria should be used at the
outset to help make regulatory decisions, develop
appropriate controls, and evaluate the effectiveness
of controls once they are implemented.
   The value of incorporating biological survey in-
formation  in regulatory programs is illustrated by
evaluations conducted  by  North Carolina.  In
To integrate biological criteria into water quality
programs, states must carefully determine where and
how data are collected to assess the biological integrity
of surface waters.

response to amendments of the Federal Water Pol-
lution Control Act requiring secondary effluent limits
for all wastewater treatment plants, North Carolina
became embroiled in a debate over whether meet-
ing secondary effluent limits (at considerable cost)
would result in better water quality. North Carolina
chose to test the effectiveness of additional treat-
merit by conducting seven chemical and biologic*
surveys before and after facility  upgrades (North
                                    21

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Statogfta/CrMwta: Ntttorml Prognm Guidon*
Carolina DNRC01984). Study results indicated that
moderate  to substantial  in-stream improvements
were observed at six of seven facilities. Biological
surveys were used  as an efficient,  cost-effective
monitoring tool  for assessing in-stream improve-
ments after facility modification. North Carolina has
also conducted comparative studies of benthic mac-
roinvertebrate surveys and  chemical-specific and
whole-effluent evaluations to assess sensitivities of
these   measures   for   detecting   impairments
(Eagleson et al. 1990).
    Narrative biological criteria provide a scientific
framework for evaluating biosurvey, bioassessment,
and biomonitoring data collected in most States. Ini-
tial application of narrative biological criteria may re-
quire only an evaluation of current work. States can
use available data to define variables for choosing
reference sites, selecting appropriate biological sur-
veys, and  assessing the response of local biota to a
variety of impacts. States should also consider the
decision criteria that will be used for determining ap-
propriate State action when impairment is found.
    Recent  efforts by  several  States to develop
biological criteria for freshwater streams provide ex-
cellent examples for how biological criteria can be
integrated into water quality programs. Some of this
work is described in the National Workshop on In-
stream Biological Monitoring and Criteria proceed-
ings which  recommended  that  "the concept  of
biological sampling should be integrated into the full
spectrum  of  State  and  Federal surface  water
programs'  (U.S. EPA  1987b). States are actively
developing  biological  assessment  and  criteria
programs; several have programs in place.
Biological Criteria in  State

Programs

    Biological  criteria  are  used   within  water
programs to  refine use designations,  establish
criteria  for determining use attainment/nonattain-
ment,  evaluate  effectiveness   of  current  water
programs, and detect and characterize previously
unknown impairments. Twenty States are currently
using some form of standardized ambient biological
assessments to determine the status of biota within
State waters. Levels of effort vary from bioassess-
ment studies to fully developed biological criteria
programs.
    Fifteen  States  are developing  aspects  of
biological assessments  that  will support  future
development of biological criteria. Colorado, Illinois,
Iowa, Kentucky, Massachusetts, Tennessee,  and
Virginia conduct biological  monitoring to  evaluate
biological conditions, but are not developing biologi-
cal criteria.  Kansas is  considering using a com-
munity  metric  for water  resource assessment.
Arizona  is planning to refine ecoregions for the
State. Delaware, Minnesota, Texas, and Wisconsin
are developing sampling and evaluation methods to
apply to future biological criteria  programs. New
York is proposing to use biological criteria for site-
specific  evaluations of water quality impairment.
Nebraska and  Vermont use  informal biological
criteria to support existing aquatic  life narratives in
their water quality standards and other regulations.
Vermont  recently  passed   a law requiring  that
biological criteria be used to regulate through  per-
mitting the indirect discharge of sanitary effluents.
    Florida  incorporated  a  specific  biological
criterion  into   State  standards  for  invertebrate
species diversity.  Species diversity within  a water-
body, as measured by a Shannon diversity index,
may not fall below 75 percent of reference values.
This criterion has been used in enforcement cases
to obtain injunctions and  monetary settlements.
Florida's approach is very specific and limits alter-
native applications.
    Four States—Arkansas,  North Carolina, Maine,
and Ohio—are  currently using biological criteria to
define  aquatic  life use classifications and enforce
water quality standards. These states have made
biological criteria an integral part of comprehensive
water quality programs.

  • Arkansas  rewrote its aquatic life use classifica-
tions for each of the State's ecoregions. This has al-
lowed many cities to design wastewater treatment
plants to meet realistic attainable dissolved oxygen
conditions as determined by the new criteria.

  • North Carolina developed biological criteria to
assess impairment to aquatic life uses written as nar-
ratives in the State water quality standards. Biologi-
cal data and criteria are used extensively to identify
waters of special concern or those with exceptional
water quality. In addition to the High Quality Waters
(HQW)  and Outstanding Resource Waters (ORW)
designations, Nutrient  Sensitive Waters (NSW)  at
risk for eutrophication are assessed using biological
                                                 22

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                                                                      Chapter* Integrating Biological Criteria
criteria. Although specific biological  measures are
not in the regulations, strengthened use of biological
monitoring  data to assess  water quality  is  being
proposed for incorporation in North Carolina's water
quality standards.

  •  Maine  has enacted a  revised  Water Quality
Classification Law specifically designed to facilitate
the use of  biological assessments. Each of four
water classes contains descriptive aquatic life condi-
tions necessary to attain that  class. Based on  a
statewide  database of macroinvertebrate  samples
collected above and below  outfalls,  Maine is now
developing a set of dichotomous keys that serve as
the biological  criteria. Maine's  program is not ex-
pected to have a significant roie in permitting, but will
be used to assess the degree of protection afforded
by effluent limitations.

  •  Ohio has instituted the most extensive use of
biological criteria for defining use classifications and
assessing  water  quality.  Biological criteria  were
developed  for Ohio  rivers  and  streams using an
ecoregional  reference site approach.  Within each of
the State's five ecoregions, criteria for three biologi-
cal indices  (two for fish  communities and one for
macroinvertebrates) were derived. Ohio successfully
uses biological criteria to  demonstrate attainment of
aquatic life uses and discover previously unknown or
unidentified  environmental degradation  (e.g., twice
as many  impaired waters  were  discovered  using
biological criteria and water chemistry together than
were found  using  chemistry alone).  The upgraded
use  designations based on  biological criteria were
upheld in Ohio courts and the Ohio EPA successfully
proposed their biological  criteria for inclusion  in the
State water quality standards regulations.

    States and EPA have learned a great deal about
the effectiveness  of integrated  biological  assess-
ments through the development of biological criteria
for freshwater streams.  This  information is par-
ticularly valuable in providing guidance on develop-
ing biological criteria for other surface water types.
As previously discussed,  EPA plans to produce sup-
porting  technical  guidance for  biological criteria
development in streams  and other surface waters.
Production  of these guidance documents will be
contingent on technical progress made on each sur-
face water type by researchers in EPA, States and
the academic community.
    EPA will also be  developing outreach  work-
shops  to provide technical assistance  to Regions
and States  working  toward the implementation of
biological  criteria programs in  State  water  quality
management  programs.  In  the  interim,  States
should use  the technical guidance currently avail-
able in the Technical Support Manual(s): Waterbody
Surveys and Assessments for Conducting Use At-
tainability Analysis (U.S. EPA1983b, 1984a,b).
    During the next  triennium,  State  effort  will be
focused on  developing narrative biological criteria.
Full implementation  and  integration  of biological
criteria will  require several years. Using  available
guidance, States can complement the adoption of
narrative  criteria  by  developing implementation
plans that include:

    1.  Defining program objectives, developing
       research protocols, and setting  priorities;

    2.  Determining the process  for establishing
       reference conditions, which includes
       developing a process to evaluate habitat
       characteristics;

    3.  Establishing biological survey protocols that
       include justifications for surface water
       classifications and selected aquatic
       community components to be evaluated;
       and

    4.  Developing a formal document describing
       the research design, quality assurance and
       quality control protocols,  and required
       training for staff.

    Whether a State  begins with narrative biological
criteria or moves to fully implement numeric criteria,
the shift of the water quality program focus from
source control to resource management represents
a natural progression in the evolution from the tech-
nology-based to water quality-based approaches in
water  quality  management.  The  addition of  a
biological perspective allows water quality programs
to more directly address the objectives of the Clean
Water Act and to place their efforts in  a context that
is more meaningful to the public.
                                                 23

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BMogieal Crittrtv NtOorml Prognm Guidance
Future Directions

    Biological criteria now focus on resident aquatic
communities  in  surface waters. They have the
potential to expand in scope toward greater ecologi-
cal integration. Ecological criteria may encompass
the ambient aquatic communities in surface waters,
wildlife species that use the same aquatic resour-
ces, and  the aquatic  community  inhabiting the
gravel and sediments underlying the surface waters
and adjacent land (hyporheic zone); specific criteria
may apply to physical habitat. These areas may rep-
resent  only a few possible options for biological
criteria in the future.
    Many wildlife species depend on aquatic resour-
ces. If  aquatic population levels decrease  or  if the
distribution of  species changes, food sources may
be sufficiently altered to cause problems for wildlife
species using  aquatic resources.  Habitat degrada-
tion that impairs aquatic species will  often impact
important wildlife habitat as well. These kinds of im-
pairments are  likely to be detected using biological
criteria  as currently formulated.  In  some cases,
however,  uptake  of  contaminants  by  resident
aquatic organisms may not result in altered struc-
ture and function of the aquatic community. These
impacts may  go undetected by  biological criteria,
but could  result in wildlife impairments because of
bioaccumulation.  Future expansion of biological
criteria to  include  wildlife  species that depend on
aquatic resources could provide a more integrative
ecosystem approach.
    Rivers may have a subsurface  flood plain ex-
tending as far as two kilometers from the river chan-
nel. Preliminary mass transport calculations made
in the Flathead River basin in Montana indicate that
nutrients discharged  from this  subsurface  flood
plain may be crucial to biotic productivity in  the river
channel (Stanford and Ward 1988). This is an unex-
plored dimension in the ecology of gravel river beds
and potentially in other surface waters.
    As discussed in Chapter 1, physical integrity is a
necessary condition for biological integrity. Estab-
lishing  the reference condition for biological criteria
requires evaluation of habitat. The rapid bioassess-
ment protocol  provides a good example of the im-
portance  of   habitat  for  interpreting biological
assessments  (Plafkin et al. 1989). However, it may
be  useful  to  more fully integrate habitat  charac-
teristics into the regulatory process by establishing
criteria based on the necessary physical structure of
habitats to support ecological integrity.
                                                24

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            Part II
The Implementation
           Process

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Biological Grrtwte National Program Guidance
    The  implementation of biological criteria requires:  (1) selection of unimpaired
    (minimal impact) surface waters to use as the reference condition for each desig-
    nated use, (2) measurement of the structure and function of aquatic communities in
    reference surface waters to establish biological criteria, and (3) establishment of a
    protocol to compare the biological criteria to biota in impacted waters to determine
    whether impairment has occurred. These elements serve as an interactive network
    that  is  particularly important during  early development of biological criteria
    where rapid accumulation of information is effective for refining both designated
    uses and developing biological criteria values.  The following chapters describe
    these three essential elements.
                                         26

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                                 Chapter  5
        The  Reference  Condition
A        key step in developing values for support-
        ing narrative and creating numeric biologi-
        cal  criteria  is  to  establish  reference
conditions; it is an essential feature of environmental
impact evaluations (Green  1979).  Reference condi-
tions are critical for environmental assessments be-
cause standard experimental controls are rarely
available. For most surface waters, baseline data
were not collected prior to an impact, thus impair-
ment must be inferred from differences between the
impact site and established references. Reference
conditions describe the characteristics of waterbody
segments least impaired by human activities and are
used to define attainable biological or habitat condi-
tions.
   Wide variability among natural surface waters
across the country resulting from climatic, landform,
and  other  geographic differences  prevents the
development of nationwide  reference conditions.
Most States are also too heterogeneous for single
reference conditions. Thus, each State, and when
appropriate, groups of States, will be responsible for
selecting and evaluating reference waters within the
State to establish biological criteria for a given sur-
face water type or category of designated use. At
least seven methods for estimating attainable condi-
tions for streams have been identified (Hughes et al.
1986). Many of these can apply to  other surface
waters. References may be established by defining
models of attainable conditions based on historical
data or unimpaired habitat  (e.g., streams in old
growth forest). The reference condition established
as before-after comparisons  or  concurrent  mea-
Reference conditions should be established by
measuring resident biota in unimpaired surface waters.
sures of the reference water and impact sites can be
based on empirical data (Hall et al. 1989).
   Currently, two principal approaches are used for
establishing the reference condition. A State may
opt to (1) identify site-specific reference sites for
each evaluation of impact or (2) select ecologically
similar regional reference sites for comparison with
impacted  sites within the same region. Both ap-
proaches  depend on evaluations of habitats to en-
sure that waters with similar habitats are compared.
The designation  of discrete habitat types is more
fully developed for streams and rivers. Development
of habitat types for lakes, wetlands, and estuaries is
ongoing.
                                            27

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Bfetogfctf Crtt*iK National Program Guidance
Site-Specific  Reference

Condition

   A site-specific  reference condition,  frequently
used to evaluate the impacts from a point discharge,
is best for surface waters with a strong  directional
flow such as in streams and rivers (the upstream-
downstream approach). However, it can also be
used for other surface  waters where gradients in
contaminant  concentration  occur  based  on
proximity to a source (the  near field-far field ap-
proach). Establishment  of a site-specific reference
condition requires  the  availability  of comparable
habitat within the same waterbody in both the refer-
ence location and the impacted area.
   A site-specific reference condition is difficult to
establish if (1) diffuse nonpoint source pollution con-
taminates most of the water body; (2) modifications
to the channel, shoreline, or bottom substrate are
extensive; (3) point sources occur at multiple loca-
tions on the waterbody; or (4) habitat characteristics
differ significantly between possible reference loca-
tions and the impact site (Hughes et al. 1986; Plaf-
kin  et  al.  1989).  In  these  cases, site-specific
reference conditions could result in underestimates
of impairment. Despite  limitations, the use of site-
specific reference conditions is often the method of
choice for  point source discharges and  certain
waterbodies, particularly when the relative impair-
ments from different local impacts need to be deter-
mined.
The Upstream-Downstream
Reference Condition

    The upstream-downstream reference condition
is best  applied to streams and  rivers  where the
habitat characteristics of the waterbody above the
point of discharge are similar to the habitat charac-
teristics of the stream below the point of discharge.
One standard procedure is to characterize the biotic
condition just above the discharge point (accounting
for possible upstream circulation) to establish the
reference condition.  The  condition below the dis-
charge  is also  measured  at several sites.  If sig-
nificant   differences  are  found  between  these
measures,  impairment of the  biota from the dis-
charge  is indicated.  Since measurements of resi-
dent biota taken in any two  sites are expected to
differ because of natural variation, more than one
biological  assessment  for  both upstream  and
downstream sites is often needed to be confident in
conclusions drawn  from these data (Green,  1979).
However, as more data are collected by a State, and
particularly if  regional characteristics of the  water-
bodies are incorporated, the basis for determining
impairment from site-specific upstream-downstream
assessments  may require fewer individual samples.
The  same measures  made below the "recovery
zone" downstream from the discharge will help
define where recovery occurs.
   The upstream-downstream reference condition
should be used with discretion since the reference
condition may be impaired from impacts upstream
from the point source of interest. In these cases it is
important  to discriminate between individual point
source impact versus overall impairment of the sys-
tem. When overall  impairment occurs, the resident
biota may be  sufficiently impaired to make it impos-
sible to detect the effect of  the target point source
discharger.
   The approach can be cost effective when one
biological  assessment of the upstream reference
condition adequately reflects the attainable  condi-
tion  of the impacted site. However,  routine com-
parisons   may  require  assessments of several
upstream  sites to adequately describe the natural
variability  of reference biota. Even so, measuring a
series of site-specific references will likely continue
to be the method of choice  for certain point source
discharges, especially  where the relative  impair-
ments from different local impacts need to be deter-
mined.
The Near Field-Far Field Reference
Condition

    The near field-far field reference condition is ef-
fective for establishing a reference condition in sur-
face waters other than rivers and  streams and is
particularly applicable for unique waterbodies (e.g.,
estuaries such as Puget Sound may not have com-
parable estuaries for comparison). To apply this
method,  two variables are  measured  (1)  habitat
characteristics, and (2) gradient of impairment. For
reference waters to be  identified within the same
waterbody, sufficient size is necessary to separate
the  reference  from  the impact area  so  that  a
gradient of impact exists. At the same time, habitat
characteristics must be comparable.
                                                28

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                                                                       Chapter 3: Thf Reftnnce Condition
    Although not fully developed, this approach may
provide an effective way to establish  biological
criteria for estuaries, large lakes, or wetlands. For
example, estuarine habitats could be defined and
possible reference waters identified using physical
and chemical variables like those selected by the
Chesapeake Bay  Program (U.S. EPA I987a, e.g.,
substrate type, salinity, pH) to establish comparable
subhabitats in an estuary. To determine those areas
least impaired, a "mussel watch" program like that
used in Narragansett Bay (i.e., captive mussels are
used as indicators of contamination, (Phelps 1988))
could establish impairment gradients. These two
measures, when combined, could form the basis for
selecting specific habitat types in areas of least im-
pairment to establish the reference condition.
Regional Reference

Conditions

    Some of the limitations of site-specific reference
conditions can be overcome by using regional refer-
ence conditions that are based on the assumption
that surface waters integrate the character of the
land they drain. Waterbodies within the same water-
shed in the same region should be more similar to
each other than to those within watersheds in dif-
ferent regions. Based on these assumptions, a dis-
tribution of aquatic regions can be developed based
on  ecological features that directly or indirectly re-
late to  water quality and quantity, such as soil type,
vegetation (land cover), land-surface form, climate,
and land  use. Maps  that  incorporate  several of
these features will provide a general purpose broad
scale ecoregional framework (Gallant et al. 1989).
    Regions of ecological similarity are based on
hydrologic,  climatic,  geologic,  or  other relevant
geographic variables that influence the nature of
biota in surface waters. To establish a regional refer-
ence condition,  surface waters of similar habitat
type are identified in definable ecological regions.
The biological integrity of these reference waters is
determined to establish the reference condition and
develop biological  criteria. These criteria are then
used to  assess impacted  surface  waters  in the
same watershed or region. There are two forms of
regional  reference conditions:  (1)  paired  water-
sheds and (2) ecoregions.
Paired Watershed Reference
Conditions

    Paired watershed reference conditions are es-
tablished to evaluate impaired waterbodies, often
impacted by multiple sources. When the majority  of
a waterbody is impaired, the upstream-downstream
or near field-far field reference condition does not
provide an adequate representation  of the unim-
paired  condition of aquatic communities  for the
waterbody. Paired watershed reference conditions
are established by identifying  unimpaired  surface
waters within the same or very similar local water-
shed that is of comparable type and  habitat. Vari-
ables to consider  when selecting the watershed
reference condition include absence of human dis-
turbance, waterbody size and other physical charac-
teristics, surrounding  vegetation,   and others  as
described in the "Regional  Reference Site Selec-
tion" feature.
    This method  has  been successfully  applied
(e.g., Hughes 1985)  and is an approach  used  in
Rapid  Bioassessment   Protocols   (Plafkin  et  al.
1989).  State use of this approach results  in good
reference conditions that can be used immediately
in current programs. This approach has the added
benefit of promoting the development of a database
on high quality waters in the State that could form
the foundation for establishing larger regional refer-
ences (e.g., ecoregions.)
Ecoregional Reference Conditions

    Reference conditions can also be developed on
a larger scale. For these references, waterbodies of
similar type are identified  in regions of ecological
similarity. To establish a regional reference condi-
tion, a set of surface waters of similar habitat type
are identified in each ecological region. These sites
must represent similar habitat type  and be repre-
sentative of the region. As with other reference con-
ditions, the biological integrity  of selected reference
waters  is determined to establish the reference.
Biological criteria can then be developed and used
to assess  impacted surface  waters in the  same
region.  Before reference conditions may be estab-
lished,  regions  of  ecological similarity must be
defined.
                                                29

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        Crtttflx NtUonU Pmgnm Guidance
       Regional Reference Site

                 Selection


       To determine specific regional reference sites
    for streams,  candidate watersheds are selected
    from  the  appropriate maps and  evaluated to
    aetermine if they are typical for the region. An
    evaluation of level of human disturbance is made
    and a number of relatively undisturbed reference
    sites  are selected from  the candidate sites.
    Generally, watersheds are chosen as regional ref-
    erence sites when they fall entirely within typical
    areas of the region.  Candidate sites are then
    selected by aerial and ground surveys. Identifica-
    tion of candidate sites is based on: (1) absence
    of  human disturbance, (2) stream size, (3) type
    of stream channel, (4) location within a natural or
    political refuge, and (5) historical records of resi-
    dent biota and possible migration barriers.
       Final selection of reference sites depends on
    a determination of minimal disturbance derived
    from  habitat evaluation made during site visits.
    For example, indicators of good quality streams in
    forested ecoregions include: (1) extensive, old,
    natural riparian vegetation;  (2) relatively high het-
    erogeneity in channel width and depth; (3) abun-
    dant  large woody debris,  coarse bottom sub-
    strate, or extensive aquatic or overhanging vege-
    tation, (4) relatively high or constant discharge;
    (5) relatively clear waters with natural color and
    odor; (6) abundant diatom, insect, and fish as-
    semblages; and (7) the presence of piscivorous
    birds and mammals.
    One frequently used method is  described  by
Omernik (1987) who combined maps of land-sur-
face form, soil, potential natural vegetation, and
land use within the conterminous United States to
generate  a map  of aquatic  ecoregions for  the
country. He also developed more detailed regional
maps.  The ecoregions defined by Omernik have
been evaluated for streams and small rivers in
Arkansas (Rohm et al. 1987), Ohio (Larsen et al.
1986; Whittier et al. 1987), Oregon (Whittier et al.
1988),  Colorado (Gallant et al. 1989), and Wiscon-
sin (Lyons 1989) and for lakes in Minnesota (Heis-
kary et  al. 1987).  State ecoregion  maps were
developed for Colorado (Gallant et al. 1989)  and
Oregon (Clarke  et al.  mss).  Maps  for the national
ecoregions  and six  multi-state  maps  of more
detailed ecoregions are available from the U.S. EPA
Environmental   Research   Laboratory,   Corvallis,
Oregon.
    Ecoregions such as those defined by Omernik
(1987) provide  only a first step  in  establishing
regional reference sites for development of the ref-
erence condition. Field site evaluation is required to
account  for  the inherent variability  within each
ecoregion. A general method  for selecting  reference
sites for streams has been described (Hughes et al.
1986). These are the same variables used for com-
parable   watershed   reference   site   selection.
Regional and on-site evaluations of biological  fac-
tors help determine specific sites that best  represent
typical but unimpaired surface water habitats within
the region. Details on this approach for streams is
described in the "Regional Reference Site Selec-
tion" feature. To date,  the regional -approach  has
been  tested on  streams,  rivers,  and lakes.  The
method appears applicable for assessing other in-
land ecosystems. To apply this approach  to wet-
lands  and  estuaries  will  require   additional
evaluation based on the relevant ecological features
of these  ecosystems  (e.g.  Brooks and Hughes,
1988).
    Ideally, ecoregional reference sites should be
as little disturbed as possible, yet represent water-
Bodies for which they  are to  serve as  reference
waters. These sites may serve as references for a
large  number of similar waterbodies (e.g.,  several
reference streams may be used to define the refer-
ence  condition  for numerous  physically  separate
streams if the reference streams contain  the same
range of stream morphology, substrate, and flow of
the other streams  within  the same  ecological
region).
    An important benefit of a regional reference  sys-
tem is the establishment of a baseline condition for
the  least  impacted  surface  waters within  the
dominant  land use pattern of the region. In many
areas a return to pristine, or presettlement, condi-
tions is impossible, and goals for waterbodies in ex-
tensively  developed  regions   could  reflect   this.
Regional  reference  sites based on the  least im-
pacted sites within a region  will help water quality
programs restore and protect the environment in a
way that is ecologically feasible.
                                                 30

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                                                                         Chapter 5: The Reference Condition
    This approach must be used with caution for two
reasons. First, in many urban, industrial, or heavily
developed agricultural regions, even  the least im-
pacted sites are seriously degraded. Basing stand-
ards or criteria on such sites will  set standards too
low if these high levels of environmental degrada-
tion are considered acceptable or  adequate. In such
degraded  regions,  alternative  sources for  the
regional reference may be needed (e.g., measures
taken from the same  region in a less developed
neighboring State or  historical records  from  the
region before serious impact occurred). Second, in
some regions  the minimally-impacted sites are not
typical of most sites in the region  and may have
remained  unimpaired precisely because  they are
unique. These two considerations  emphasize the
need to select reference sites very carefully, based
on solid quantitative data  interpreted  by profes-
sionals familiar with the biota of the region.
   Each State,  or groups of States,  can select a
series of regional reference sites that represent the
attainable conditions for aach region. Once biologi-
cal criteria are established using this approach, the
cost for evaluating local impairments is often lower
than a series of measures of site-specific reference
sites.  Using paired watershed reference conditions
immediately in regulatory programs will provide the
added  benefit  of building  a  database for the
development of regions of ecological similarity.
                                                31

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                                 Chapter  6
            The  Biological  Survey
A        critical element of biological criteria is the
        characterization of biological communities
        inhabiting surface waters. Use of biological
data is not new; biological information has been used
to  assess impacts from pollution  since the 1890s
(Forbes  1928),  and most States  currently  incor-
porate biological information in their decisions about
the quality of surface waters. However, biological in-
formation can be obtained  through  a variety of
methods, some of which are more effective than
others for characterizing  resident aquatic  biota.
Biological criteria are developed using biological sur-
veys;  these  provide  the  only direct method for
measuring the structure and function  of an aquatic
community.
Different subhabitat within the same surface water will
contain unique aquatic community components. In
fast-flowing stream segments species such as (1) black
fly larva; (2) brook trout; (3) water penny; (4) crane fly
larva; and (5) water moss occur.
                                               However, In slow-flowing stream segments, species
                                               like (1) water strider (2) smallmouth bass; (3) crayfish;
                                               and (4) fingernail dams are abundant.
   Biological survey study design is of critical im-
portance to criteria development. The design must
be scientifically rigorous to provide the basis for
legal action, and be biologically relevant to detect
problems of regulatory concern. Since it is not finan-
cially or technically feasible  to evaluate all or-
ganisms in an entire ecosystem at all times, careful
selection of community components, the time and
place  chosen for assessments, data  gathering
methods used, and the consistency  with which
these variables are applied will determine the suc-
cess of the  biological criteria program.  Biological
surveys must therefore be carefully planned to meet
scientific and legal requirements, maximize informa-
tion, and minimize cost.
                                            33

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              NWtond Program Guklanc*
    Biological surveys can  range from collecting
samples  of  a single  species  to comprehensive
evaluations of an entire ecosystem. The first ap-
proach is difficult to interpret for community assess-
ment;  the  second  approach  is  expensive  and
impractical. A balance between these extremes can
meet  program needs. Current approaches range
between detailed ecological  surveys, biosurveys of
targeted community components, and biological in-
dicators (e.g., keystone species). Each  of these
biosurveys has advantages and limitations. Addi-
tional  discussion  will  be  provided in  technical
guidance under development.
    No single type of approach to biological surveys
is always best. Many factors affect the value of the
approach, including seasonal variation, waterbody
size, physical boundaries, and other natural charac-
teristics.  Pilot testing  alternative approaches  in
State waters may be the best way to determine the
sensitivity of specific methods for evaluating biologi-
cal integrity of local waters. Due to the number of al-
ternatives available and the diversity of ecological
systems,  individuals   responsible  for  research
design should be experienced biologists with exper-
tise in the local and regional ecology of target sur-
face  waters.  States  should  develop  a  data
management program that  includes data analysis
and evaluation and standard operating procedures
as part of a Quality Assurance Program Plan.
    When developing  study designs for biological
criteria, two  key elements to consider include (1)
selecting aquatic community components that will
best represent the biological integrity of State sur-
face  waters  and  (2)  designing data collection
protocols to  ensure the  best representation of the
aquatic community. Technical  guidance  currently
available to aid the development of study design in-
clude: Water Quality Standards Handbook (U.S.
EPA1983a),  Technical Support Manual: Waterbody
Surveys and Assessments  for Conducting Use At-
tainability Analyses (U.S. EPA  1983b);  Technical
Support Manual: Waterbody Surveys and Assess-
ments for Conducting Use Attainability Analyses,
Volume II: Estuarine  Systems (U.S. EPA 1984a);
and Technical Support Manual: Waterbody Surveys
and Assessments for Conducting Use Attainability
Analyses, Volume III: Lake  Systems (U.S.  EPA
1984b).  Future technical guidance will  build  on
these documents and  provide specific guidance for
biological criteria development.
Selecting Aquatic

Community  Components

   Aquatic  communities  contain  a  variety  of
species that represent different trophic  levels,
taxonomic groups, functional characteristics, and
tolerance  ranges.  Careful  selection  of  target
taxonomic groups can provide a balanced assess-
ment that is sufficiently broad to describe the struc-
tural  and  functional   condition  of  an  aquatic
ecosystem, yet be sufficiently practical to use on a
daily basis (Plafkin et al. 1989; Lenat 1988). When
selecting community components to include in a
biological assessment, primary emphasis should go
toward including species or taxa that (1) serve as ef-
fective indicators  of high biological integrity (i.e.,
those likely to live in unimpaired waters), (2) repre-
sent a range of pollution tolerances, (3) provide pre-
dictable, repeatable results, and (4) can be readily
identified by trained State personnel.
    Fish, macroinvertebrates, algae, and zooplank-
ton are most commonly used in current bioassess-
ment  programs. The taxonomic groups chosen will
vary depending on the type  of aquatic ecosystem
being assessed and the type of  expected impair-
ment. For example, benthic macroinvertebrate and
fish  communities  are taxonomic  groups often
chosen for flowing fresh water. Macroinvertebrates
and fish both provide  valuable ecological  informa-
tion while fish  correspond  to the  regulatory and
public perceptions  of water quality and  reflect
cumulative  environmental stress  over longer time
frames. Plants  are often  used In  wetlands, and
algae are useful in lakes and estuaries to assess
eutrophication. In marine systems, benthic macroin-
vertebrates and submerged aquatic vegetation may
provide key community components. Amphipods,
for example, dominate many aquatic communities
and  are more  sensitive than  other invertebrates
such as polychaetes and molluscs to a wide variety
of pollutants including  hydrocarbons and heavy me-
tals  (Reich  and  Hart 1979; J.D.  Thomas, pers.
comm.).
    It is beneficial to  supplement standard  groups
with  additional community  components  to meet
specific goals, objectives, and resources of the  as-
sessment program. Biological surveys that use two
or three taxonomic groups (e.g., fish,  macroinver-
tebrates, algae) and, where appropriate, include dif-
ferent trophic  levels within  each  group  (e.g.,
primary, secondary, and tertiary consumers)  w II
                                               34

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                                                                           Chapter &  The Biological Survey
provide  a  more  realistic  evaluation  of  system
biological  integrity.  This is analogous to  using
species  from two  or  more  taxonomic groups  in
bioassays. Impairments  that are difficult to detect
because of the temporal or spatial habits or the pol-
lution tolerances of one group may be revealed
through  impairments in different species or as-
semblages (Ohio EPA 1988a).
    Selection  of aquatic community components
that show different sensitivities and responses  to
the same perturbation will aid in identifying the na-
ture of a problem. Available data on the ecological
function, distribution, and abundance of species in a
given habitat will  help  determine  the most ap-
propriate  target  species  or taxa for  biological sur-
veys in  the  habitat. The selection  of  community
components should also depend on the ability of the
organisms to be accurately identified  by  trained
State  personnel.  Attendent with  the biological
criteria program should be the development  of iden-
tification keys for the organisms selected for study
in the biological survey.
Biological Survey Design

    Biological surveys that measure the structure
and function of aquatic communities will provide the
information needed for biological criteria develop-
ment. Elements of community structure and function
may be evaluated using a series of metrics. Struc-
tural metrics describe the  composition  of  a com-
munity,  such as  the  number of different species,
relative  abundance of specific species, and number
and relative  abundance of tolerant and intolerant
species. Functional metrics describe the ecological
processes of the community. These may  include
measures such as community photosynthesis or
respiration. Function  may also be estimated from
the proportions of various feeding groups (e.g., om-
nivores, herbivores, and insectivores, or shredders,
collectors, and  grazers).  Biological surveys  can
offer variety and flexibility in application. Indices cur-
rently available are primarily for freshwater streams.
However, the approach has been used for lakes and
can be developed for estuaries and wetlands.
Selecting the metric

    Several  methods are  currently available  for
measuring the relative structural and functional well-
being of fish assemblages in  freshwater streams,
such as the Index of Biotic Integrity (IBI); Karr 1981;
Karr et al. 1986; Miller et al. 1988) and the Index of
Well-being (IWB; Gammon 1976,  Gammon et al.
1981). The IBJ  is one of the more  widely used  as-
sessment methods. For additional detail, see  the
"Index of Biotic  Integrity' feature.
      Index of Biotic Integrity

       The Index of Biotic Integrity (IBI) is commonly
    used for fish community analysis (Karr 1981). The
    original IBI was comprised of T2 metrics:

    • six metrics evaluate species richness and
       composition

         ' number of species
         ' number of darter species
         • number of sucker species
         • number of sunfish species
         • number of intolerant species
         • proportion of green sunfish

    • three metrics quantify trophic composition
         ' proportion of omnivores
         ' proportion of insectivorous cyprinids
         * proportion ofpiscivores

    • three metrics summarize fish abundance and
       condition information
         • number of individuals in sample
         * proportion of hybrids
         • proportion of individuals with disease -

       Each metric is scored 1 (worst). 3, or 5 (best),
    depending on how the field data compare with an
    expected value obtained from reference sites. A/I
    12 metric values are then summed to provide an
    overall index value  that  represents relative in-
    tegrity. The IBI  was designed  for midwestern
    streams; substitute metrics reflecting the  same
    structural and  functional characteristics   have
    been created to accommodate regional variations
    in fish assemblages (Miller et al. 1988).
                                                35

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Btotogial Crtttft* National Program
    Several  indices that evaluate more than one
community characteristic are also available for as-
sessing  stream  macroinvertebrate  populations.
Taxa richness, EPT taxa (number of taxa of the in-
sect orders Ephemeroptera, Plecoptera, and Tricop-
tera),  and species pollution tolerance values  are a
few of several components  of these macroinver-
tebrate assessments. Example indices include the
Invertebrate  Community  Index  (1CI;  Ohio  EPA,
1988) and Hilsenhoff Biotic Index (HBI;  Hilsenhoff,
1987).
    Within these metrics specific information on the
pollution tolerances of different species within a sys-
tem will help define the type of impacts occurring in
a waterbody. Biological indicator  groups (intolerant
species,  tolerant species,  percent of diseased or-
ganisms)  can  be used for evaluating  community
biological integrity if sufficient data have been col-
lected to support conclusions drawn from the in-
dicator  data.  In  marine  systems, for example,
amphipods have been used  by  a number  of re-
searchers as  environmental  indicators (McCall
1977; Botton 1979; Meams and Word 1982).
Sampling design

    Sampling design and statistical protocols are re-
quired to reduce sampling  error and evaluate the
natural variability of biological responses that are
found  in  both  laboratory  and  field data.  High
variability reduces the power of a statistical test to
detect real impairments (SokaJ and  Rohlf, 1981).
States may reduce  variability by refining sampling
techniques and protocol to decrease variability in-
troduced during data  collection, and increase the
power of the evaluation by increasing the number of
replications.  Sampling techniques are refined,  in
part, by collecting a representative sample of resi-
dent biota from the same component  of the aquatic
community from the same habitat type in the same
way  at  sites  being  compared. Data  collection
protocols  should incorporate  (1) spatial  scales
(where and how samples are collected) and (2) tem-
poral scales  (when data  are  collected)  (Green,
1979):

   • Spatial Scales refer to the wide variety of sub-
     habitats  that exist within  any surface water
     habitat.  To account for subhabitats, adequate
     sampling protocols  require selecting  (1) the
     location  within  a habitat where  target groups
    reside and (2) the method for collecting data on
    target groups. For example, if fish are sampled
    only from fast flowing riffles within stream A, but
    are sampled from slow flowing pools in stream
    B, the data will not be comparable.

    Temporal Scales refer to aquatic  community
    changes that occur over time because of diurnal
    and life-cycle changes in organism behavior or
    development, and seasonal or annual changes
    in the environment. Many organisms go through
    seasonal life-cycle changes that dramatically
    affect their presence  and  abundance in the
    aquatic  community.  For example, macroinver-
    tebrate data collected  from stream  A in March
    and stream B in May, would not be comparable
    because the emergence of insect adults after
    March would significantly alter the  abundance
    of subadults found in stream B in May. Similar
    problems would occur  if algae were  collected in
    lake A during the dry season and lake B during
    the wet season.
    Reid sampling protocols that produce  quality
assessments from a limited number of site visits
greatly enhance the utility of the sampling  techni-
que.  Rapid  bioassessment  protocols,  recently
developed for assessing streams, use standardized
techniques to quickly gather physical, chemical, and
biological quantitative data that can assess changes
in biological integrity  (Plafkin et al.  1989). Rapid
bioassessment   methods  can  be   cost-effective
biological assessment approaches when they have
been verified with more comprehensive evaluations
for the habitats and region where they are to be ap-
plied.
    Biological survey methods such as the IBI for
fish and ICI for macroinvertebrates were developed
in streams and rivers and have yet to be applied to
many ecological regions. In addition, further re-
search is  needed to  adapt the approach to lakes,
wetlands,  and estuaries, including the development
of alternative structural or functional endpoints. For
example,  assessment  methods  for  algae  (e.g.
measures of biomass, nuisance bloom frequency,
community structure) have been used for lakes. As-
sessment  metrics  appropriate  for  developing
biological  criteria for lakes,  large rivers, wetlands,
and estuaries are being developed and tested so
that a multi-metric approach can be effectively used
for all surface waters.
                                                36

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                            Chapter  7
             Hypothesis  Testing:
    Biological  Criteria  and  the
              Scientific  Method
     Biological criteria are applied in the standards
     program by testing hypotheses about the
     biological  integrity of  impacted surface
waters.  These  hypotheses   include  the  null
hypothesis—the designated use of the waterbody is
not impaired—and alternative hypotheses such as
the designated use of the waterbody is impaired
(more specific hypotheses can also be generated
that predict the type(s) of impairment). Under these
hypotheses specific predictions are generated con-
cerning the kinds and numbers of organisms repre-
senting community structure and function expected
or found in unimpaired habitats. The kinds and num-
bers of organisms surveyed in unimpaired waters
are used to establish the biological criteria. To test
the alternative  hypotheses, data collection and
analysis procedures are used to compare the criteria
to comparable measures of community structure and
function in impacted waters.
Hypothesis Testing

   To detect differences of biological and regula-
tory concern between biological criteria and ambient
biological integrity at a test site, it is important to es-
tablish the sensitivity of the evaluation. A10 percent
difference in condition is more difficult to detect than
a 50 percent difference. For the experimental/sur-
vey design to be effective, the level of  detection
should be predetermined to establish sample size
Multiple impacts in the same surface water such as
discharges of effluent from point sources, leachate from
landfills or dumps, and erosion from habitat degradation
each contribute to impairment of the surface water. All
impacts should be considered during the diagnosis
process.
for data  collection  (Sokal  and  Rohlf 1981).
Knowledge of expected natural variation, experi-
mental error, and the kinds of detectable differences
that can be expected will help determine sample
                                     37

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Biological Criteria: National Program Guidance
size and location. This forms the basis for defining
data quality objectives, standardizing data collection
procedures,   and  developing  quality  assurance/
quality control standards.
    Once data are collected and analyzed, they are
used to test the hypotheses to determine if charac-
teristics of the resident biota at a test site are sig-
nificantly different from  established criteria values
for a comparable habitat. There are three  possible
outcomes:

    1. The use is impaired when survey design and
      data analyses are sensitive enough to detect
      differences of regulatory importance, and
      significant differences were detected. The
      next step is to diagnose the cause(s) and
      source(s)  of impairment.

    2. The biological criteria are met when survey
      design and data analyses are sensitive
      enough to detect differences of regulatory
      significance, but no differences were found.
       In this case, no action is required by States
      based on these measures. However, other
      evidence may indicate impairment (e.g.,
      chemical criteria are violated; see below).

    3. The outcome is indeterminate when survey
      design and data analyses are not sensitive
       enough to detect differences of regulatory
      significance, and no differences were
      detected.  If a State or Region determines
      that this is occurring, the development of
       study design and evaluation for biological
      criteria was incomplete. States must then
      determine whether they will accept the
      sensitivity of the survey or conduct
      additional surveys to increase the power of
      their analyses. If the sensitivity of the
      original survey Is accepted, the State should
       determine what magnitude of difference the
       survey is capable of detecting. This will aid
       in re-evaluating research design and desired
       detection limits. An indeterminate outcome
       may also occur if the test site and the
       reference conditions were not comparable.
       This variable may also require re-evaluation.

    As with all scientific studies, when implementing
biological criteria, the purpose of hypothesis testing
is to determine if the data support the conclusion
that the null hypothesis is false (i.e., the designated
use  is  not  impaired in a  particular waterbody).
Biological criteria  cannot prove  attainment. This
reasoning provides the basis for emphasizing inde-
pendent  application  of   different  assessment
methods (e.g., chemical verses biological criteria).
No type of criteria can "prove" attainment; each type
of criteria can disprove attainment.
   Although this discussion is limited  to the null
and  one alternative hypothesis,  it is  possible  to
generate  multiple working  hypotheses  (Popper,
1968) that promote the diagnosis of water quality
problems when they exist. For example, if physical
habitat limitations are believed to be causing impair-
ment   (e.g.,   sedimentation)   one   alternative
hypothesis could  specify the loss of  community
components sensitive to this impact. Using multiple
hypotheses  can maximize  the  information gained
from each study. See the Diagnosis section for addi-
tional discussion.
Diagnosis
    When impairment of the  designated use  is
found using  biological criteria, a diagnosis of prob-
able cause of impairment is the next step for im-
plementation. Since biological criteria are primarily
designed  to  detect   water  quality impairment,
problems are likely to  be identified without a known
cause. Fortunately the  process of  evaluating test
sites for biological impairment  provides significant
information to aid in determining cause.
    During diagnostic evaluations, three main im-
pact categories should be  considered:  chemical,
physical, and  biological. To begin  the diagnostic
process two questions are posed:
    • What are the obvious causes of impairment?

    • If no obvious causes are apparent, what
     possible causes do the biological data
     suggest?

    Obvious causes such as habitat degradation,
point source discharges, or  introduced species are
often identified during the course of a normal field
biological assessment. Biomonitoring programs nor-
mally provide knowledge of potential sources  of im-
pact and  characteristics of the habitat. As  such,
diagnosis is partly incorporated into many existing
State  field-oriented  bioassessment  programs.  If
more than one impact source is obvious, diagnosis
                                                 38

-------
 will require determining which impact(s) is the cause
 of impairment or the extent to which each impact
 contributes to impairment. The nature of the biologi-
 cal impairment can guide evaluation (e.g., chemical
 contamination may  lead  to  the  loss  of sensitive
 species, habitat degradation may result  in loss of
 breeding habitat for certain species).
     Case studies illustrate  the  effectiveness  of
 biological criteria in identifying  impairments and
 possible sources. For example,  in  Kansas  three
 sites on Little Mill Creek were assessed using Rapid
 Bioassessment Protocols (Plafkin et al. 1989; see
 Fig. 4).  Based  on  the  results of a comparative
 analysis,  habitats at the three  sites were  com-
 parable and of high  quality. Biological impairment,
 however, was identified at two of the three sites and
 directly related to proximity to a  point source dis-
 charge from a sewage treatment plant. The severely
 impaired Site (STA  2) was located  approximately
 100 meters downstream from the  plant. The slightly
 impaired Site (STA 3) was located between one and
 two miles downstream from the plant. However, the
 unimpaired Site (STA 1(R)) was approximately 150
 meters upstream from the plant (Plafkin et al. 1989).
 This simple example illustrates the basic principles
 of diagnosis. In this  case the  treatment plant  ap-
 pears  responsible for impairment of the resident
 biota  and  the  discharge needs  to  be evaluated.
                                                                              Chapter 7: Hypothesis Tasting
Based on the biological survey the results are clear.
However, impairment  in  resident  populations  of
macroinvertebrates probably would not have been
recognized using more traditional methods.
    In Maine, a more complex problem arose when
effluents from a textile plant met chemical-specific
and effluent toxicity criteria, yet a biological survey
of downstream biota revealed up to 80 percent
reduction in invertebrate richness below  plant out-
falls. Although the source of impairment seemed
clear, the cause of impairment was more  difficult to
determine.  By engaging in a diagnostic evaluation,
Maine was able to determine that the discharge con-
tained   chemicals   not  regulated  under  current
programs and that  part of the toxicity effect was due
to the  sequential   discharge  of  unique  effluents
(tested  individually these  effluents were  not toxic;
when exposure was  in  a  particular  sequence,
toxicity occurred). Use of biological criteria resulted
in the detection and diagnosis of this  toxicity prob-
lem, which allowed Maine to develop workable alter-
native operating procedures for the textile industry
to correct  the problem (Courtemanch 1989,  and
pers. comm.).
    During  diagnosis it is important to  consider and
discriminate among multiple sources of impairment.
In a North Carolina stream (see Figure 5) four sites
were evaluated using rapid bioassessment techni-
 Figure 4. —Kansas: Benthic e.oassessment of Little Mill Creek (Little Mill Creek = Site-Specific Reference)
 Relationship of Habitat and Bioassessment
     100
                                                                                              100
                                     Habitat Quality (% of Reference)
Fig. 4: Three stream segments sampled in a stream m Kansas using Rapid Bioassessment Protocols (Plafkin et al 1989) revea.ea
significant impairments at sites below a sewage treatment plant.                                    '
                                                  39

-------
Biologic*! Crlterix National Program Guidance
Figure 5.—The Relationship Between Habitat Quality and Benthic Community Condition at the North Carolina
Pilot Study Site.
                                                                                              100
                                     Habitat Quality (% of Reference)
Fig. 5: Distinguishing between point and nonpomt sources of impairment requires an evaluation of the nature and magnitude
of different sites in a surface water. (Plafkin, et al. 1989)
ques. An ecoregional reference site (R) established
the highest level  of biological integrity  for that
stream type. Site (1), well upstream  from a local
town, was used as  the upstream reference condi-
tion. Degraded conditions at Site (2) suggested non-
point  source  problems  and  habitat  degradation
because of  proximity to  residential areas on the
upstream edge of town.  At Site (3) habitat altera-
tions, nonpoint runoff, and point source discharges
combined to severely degrade resident biota. At this
site,  sedimentation  and  toxicity  from municipal
sewage treatment effluent appeared responsible for
a major  portion of  this degradation.  Site (4),  al-
though several mites downstream from town, was
still impaired  despite significant improvement in
habitat quality.  This suggests that  toxicity from
upstream discharges may  still be occurring  (Bar-
bour,  1990 pers. comm.).  Using these kinds of com-
parisons, through a diagnostic procedure and  by
using available chemical and biological assessment
tools, the relative effects of impacts can be deter-
mined so that  solutions can be formulated to im-
prove water quality.
    When point and nonpoint  impact  and  physical
habitat degradation occur simultaneously, diagnosis
may require the combined use of biological, physi-
cal, and chemical evaluations to discriminate be-
tween these impacts. For example, sedimentation of
a stream  caused by logging practices  is likely to
result in a decrease in species that require  loose
gravel for spawning but increase species naturally
adapted to fine sediments. This shift in  community
components correlates well with the observed  im-
pact. However, if the impact is a point source dis-
charge or  nonpoint runoff of toxicants, both species
types are  likely to be impaired whether  sedimenta-
tion occurs or not (although gravel breeding species
can  be expected to  show greater impairment if
sedimentation  occurs).  Part  of  the  diagnostic
process is derived from an understanding of  or-
ganism sensitivities to different kinds of impacts and
their habitat requirements. When habitat is good but
water quality  is poor, aquatic  community  com-
ponents sensitive to toxicity will be  impaired. How-
ever, if both habitat and water quality degrade,  the
resident community  is  likely to  be composed of
tolerant and opportunistic species.
    When an impaired use cannot be easily related
to an obvious  cause,  the  diagnostic process  be-
comes investigative and iterative. The iterative diag-
nostic process as shown  in Figure 6 may require
additional time and resources to verify cause and
source.  Initially,  potential  sources  of  impact  are
identified and mapped to determine location relative
                                                 40

-------
                                                                              Chapter r.  Hypothesis Testing
Figure 6.—Diagnostic Process

           Establish Biological Criteria

                       I
Conduct Field Assessment to Determine Impairment
               Yes
No'
                 *
                                      o Further
                                       Action
     Evaluate Data to Determine
          Probable Cause
   Generate Testable Hypotheses
        for Probable Cause
                 I
          Collect Data and
          Evaluate Results
                I
   No Apparent Cause

           I
i Propose New Alternative
' Hypotheses and Collect
        New Data
                               Obvious Cause
                                     I
                            Formulate Remedial (
                                  Action
to the area suffering from biological impairment. An
analysis of the physical, chemical,  and biological
characteristics of the study area will help identify the
most likely sources and determine which data will
be most valuable. Hypotheses that distinguish be-
tween  possible causes of  impairment should be
generated. Study design and appropriate data col-
lection procedures need to be developed to test the
hypotheses. The severity of  the impairment, the dif-
ficulty  of diagnosis,  and the  costs involved will
determine how many  iterative loops will be  com-
pleted in the diagnostic process.
    Normally,  diagnoses of biological  impairment
are  relatively  straightforward.  States  may use
biological criteria as a method to confirm impairment
from a known source  of impact. However, the diag-
nostic process provides an effective way to identify
unknown impacts and diagnose their cause so that
corrective action can be devised and implemented.
Fig. 6. The diagnostic process is a stepwise process for
determining the cause of impaired biological integrity in sur-
face waters It may require multiple hypotheses testing and
more than one remedial plan
                                                  41

-------
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                                                            44

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                              Appendix A
            Common  Questions  and
                        Their  Answers
   Q. How will implementing biological criteria
benefit State water quality programs?

   A. State water quality programs will benefit from
biological criteria because they:
   a) directly assess impairments in ambient
      biota from adverse impacts on the
      environment;

   b) are defensible and quantifiable;

   c) document improvements in water quality
      resulting from agency action;

   d) reduce the likelihood of false positives (i.e.,
      a conclusion that attainment is achieved
      when it is not);

   e) provide information on the integrity of
      biological systems that is compelling to the
      public.


   Q. How will biological criteria be used in a
permit program?

   A. When permits  are renewed, records from
chemical analyses and biological assessments are
used to  determine if the  permit has  effectively
prevented degradation and led to improvement. The
purpose for this evaluation is to determine whether
applicable water quality standards were achieved
under the expiring  permit and to decide if changes
are needed. Biological surveys and criteria are par-
ticularly effective  for  determining the  quality of
waters  subject  to permitted  discharges.  Since
biosurveys provide ongoing integrative evaluations
of the biological integrity of resident biota, permit
writers can make informed decisions on whether to
maintain or restrict permit limits.

   Q. What expertise and staff will be needed to
implement a biological criteria program?

   A. Staff with sound knowledge of State aquatic
biology and scientific protocol are needed to coor-
dinate a biological  criteria program.  Actual field
monitoring could be accomplished by summer-hire
biologists led by permanent staff aquatic biologists.
Most States employ aquatic biologists for monitor-
ing trends or issuing site-specific permits.

   Q. Which management personnel should be
involved in a biologically-based approach?

   A.  Management personnel from each area
within the standards and monitoring programs
should be involved in this approach, including per-
mit engineers,  resource  managers, and  field per-
sonnel.

   Q. How much will this approach cost?

   A. The cost of developing biological criteria is a
State-specific question depending upon many vari-
ables. However, States that have implemented a
biological criteria program have found it to be cost
effective (e.g.,  Ohio). Biological criteria provide an
integrative assessment over time.  Biota reflect mul-
tiple  impacts. Testing for impairment of resident
aquatic communities  can actually  require less
monitoring than would be required to detect many
impacts using  more traditional  methods  (e.g.,
chemical testing for episodic events).
                                          45

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Bfotoflica/Criteria: National Program Guidance
    Q. What are some concerns of dischargers?

    A. Dischargers are  concerned that biological
criteria will  identify impairments that may be er-
roneously attributed to  a discharger who is  not
responsible. This is a legitimate concern  that the
discharger  and  State must address  with  careful
evaluations and  diagnosis of cause of impairment.
However, it is particularly important to ensure that
waters used for the reference condition are not al-
ready  impaired  as may  occur when conducting
site-specific upstream-downstream evaluations. Al-
though a discharger may be contributing to surface
water degradation, it may be hard to detect using
biosurvey methods if the waterbody is also impaired
from other sources. This can be evaluated by test-
ing the possible toxicity of effluent-free reference
waters on sensitive organisms.
    Dischargers  are also  concerned  that  current
permit limits may  become more stringent if it is
determined  that meeting chemical and whole-ef-
fluent  permit  limits are not  sufficient to  protect
aquatic life  from discharger activities. Alternative
forms of regulation may be needed; these are not
necessarily  financially burdensome but could in-
volve additional expense.
    Burdensome monitoring requirements are addi-
tional  concerns. With  new rapid bioassessment
protocols available for streams, and under develop-
ment for other surface waters, monitoring  resident
biota is becoming more straightforward. Since resi-
dent biota  provide an integrative measure of en-
vironmental  impacts  over  time,  the  need  for
continual  biomonitoring  is actually  lower  than
chemical analyses and  generally  less expensive.
Guidance is being developed to establish accept-
able research protocols, quality assurance/quality
control programs and training opportunities to en-
sure that adequate guidance is available.


    Q. What are the concerns of
environmentalists?

    A. Environmentalists are concerned that biologi-
cal criteria could be used to alter restrictions on dis-
chargers if biosurvey data indicate attainment of a
designated  use  even  though  chemical  criteria
and/or whole-effluent toxicity evaluations predict im-
pairment. Evidence suggests that this occurs infre-
quently (e.g., in  Ohio,  6 percent  of  431  sites
evaluated  using  chemical-specific  criteria   and
biosurveys resulted in this disagreement). In those
cases where evidence suggests more than one con-
clusion, independent application applies. If biologi-
cal criteria suggest  impairment  but  chemical-
specific and/or whole-effluent toxicity implies attain-
ment of the use, the cause for impairment of the
biota is to be evaluated and,  where appropriate,
regulated. If whole effluent and/or chemical-specific
criteria imply impairment but no  impairment is found
in resident biota, the whole-effluent and/or chemi-
cal-specific criteria provide the basis for regulation.


    Q. Do biological criteria have to be codified
in State regulations?

    A.  State water quality standards require  three
components:  (1) designated uses, (2)  protective
criteria, and  (3) an  antidegradation clause. For
criteria to be enforceable they  must be  codified  in
regulations. Codification could involve general nar-
rative  statements of  biological  criteria,  numeric
criteria, and/or criteria accompanied by specific test-
ing  procedures.  Codifying  general  narratives
provides the  most flexibility—specific methods  for
data collection the least flexibility—for incorporating
new data and improving data gathering methods as
the biological criteria program develops. States
should  carefully consider how  to codify  these
criteria.
    Q. How will biocriteria fit into the agency's
method of implementing standards?

    A. Resident  biota integrate  multiple impacts
over time and can detect impairment from known
and unknown causes. Biocriteria can  be used  to
verify improvement in water quality in response  to
regulatory efforts and detect continuing degradation
of waters. They provide a framework for developing
improved best management practices for nonpoint
source impacts. Numeric criteria can provide effec-
tive monitoring criteria for inclusion in permits.


    Q. Who determines the values for biological
criteria and decides whether a waterbody meets
the criteria?

    The process of developing biological criteria, in-
cluding refined use classes, narrative criteria, and
numeric criteria,  must include agency managers,
staff biologists, and the public through  public hear-
ings and comment. Once criteria are  established,
determining attainment\nonattainment of a use re-
                                                46

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                                                             Appendix A: Common Questions and Their Answers
quires biological and statistical evaluation based on
established protocols. Changes in the criteria would
require the same steps as the initial criteria: techni-
cal modifications by biologists, goal clarification by
agency managers, and public hearings. The key to
criteria development and revision is a clear state-
ment of measurable objectives.


    Q. What additional information is available
on developing and using biological criteria?

    A. This  program guidance  document  will  be
supplemented by the document  Biological  Criteria
Development by States that includes case histories
of State implementation of biological criteria as nar-
ratives, numerics, and some data procedures. The
purpose for the document is to expand on material
presented in Part I. The document will be available
in October 1990.
    A general Biological Criteria Technical Refer-
ence  Guide will also be available  for distribution
during FY 1991. This document  outlines  basic ap-
proaches for developing biological criteria in all sur-
face  waters  (streams,  rivers,  lakes,  wetlands,
estuaries). The primary focus of the document is to
provide a reference guide to scientific literature that
describes approaches and methods used to deter-
mine  biological integrity of specific surface water
types.
    Over the next triennium more detailed guidance
will be produced that focuses on each surface water
type (e.g., technical guidance for streams will  be
produced during FY 91). Comparisons of different
biosurvey approaches will be included for accuracy,
efficacy, and cost effectiveness.
                                                47

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                       Appendix B
    Biological  Criteria Technical
                Reference Guide
Table of Contents (tentative)

SECTION 1. INTRODUCTION
   a Purpose of the Technical Support Document
   a Organization of the Support Document

SECTION 2. CONCEPTUAL FRAMEWORK FOR BIOLOGICAL CRITERIA
   a Definitions
   a Biocriteria and the Scientific Method
   o Hypothesis Formulation and Testing
   3 Predictions
   a Data Collection and Evaluation

SECTION 3. QUALITY ASSURANCE/QUALITY CONTROL
   a Data Quality Objectives
   a Quality Assurance Program Plans and Project Plans
   a Importance of QA/QC for Bioassessment
   a Training
   a Standard Procedures
   a Documentation
   a Calibration of Instruments

SECTION 4. PROCESS FOR THE DEVELOPMENT OF BIOCRITERIA
   a Designated Uses
   a Reference Site or Condition
   a Biosurvey
   a Biological Criteria
                               49

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Biological Critoria: National Program Guidance

SECTION 5. BIOASSESSMENT STRATEGIES TO DETERMINE BIOLOGICAL INTEGRITY
    a Detailed Ecological Reconnaissance
    a Biosurveys of Targeted Community Segments
    a Rapid Bioassessment Protocols
    a Bioindicators

SECTION 6. ESTABLISHING THE REFERENCE CONDITION
    a Reference Conditions Based on Site-Specific Comparisons
    a Reference Conditions Based on Regions of Ecological Similarity
    a Reference Conditions Based on Habitat Assessment

SECTION 7. THE REFERENCE CATALOG

SECTION 8. THE INFLUENCE OF HABITAT ON  BIOLOGICAL INTEGRITY
    a Habitat Assessment for Streams and Rivers
    a Habitat Assessment for Lakes and Reservoirs
    a Habitat Assessment for Estuaries and Near-Coastal Areas
    a Habitat Assessment for Wetlands

SECTION 9. BIOSURVEY METHODS TO ASSESS BIOLOGICAL INTEGRITY
    a Biotic Assessment in Freshwater
    G Biotic Assessment in Estuaries and Near-Coastal Areas
    a Biotic Assessment in Wetlands

SECTION 10. DATA ANALYSIS
    a Sampling Strategy and Statistical Approaches
    a Diversity Indices
    a Biological Indices
    a Composite Community Indices

APPENDIX A. Freshwater Environments
APPENDIX B. Estuarine and Near-Coastal Environments
APPENDIX C. Wetlands Environments
APPENDIX D.  Alphabetical Author/Reference Cross Number Index for the Reference Catalog
APPENDIX E. Reference Catalog Entries
LIST OF FIGURES
    o Figure 1 Bioassessment decision matrix
    a Figure 2 Specimen of a reference citation in the Reference Catalog
                                          50

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                             Appendix  C
                 Biological  Criteria
            Development  by  States
Table of Contents (tentative)
I.   Introduction

II.   Key Concepts

III.   Biological Criteria Across the 50 States

IV.   Case Study of Ohio
    A.  Introduction
       1.  Derivation of Biological Criteria
       2.  Application of Biological Criteria
    B.  History
       1.  Development of Biological Criteria
       2.  Current Status of Biological Criteria
    C.  Discussion
       1.  Program Resources
       2.  Comparative Cost Calculations
       3.  Program Evaluation

V.   Case Study of Maine
    A.  Introduction
       1.  Derivation of Biological Criteria
       2.  Application of Biological Criteria
    B.  History
       1.  Development of Biological Criteria
       2.  Program Rationale
    C.  Discussion
       1.  Program Resources
       2.  Program Evaluation

VI.   Case Study of North Carolina
    A.  Introduction
       1.  Derivation of Biological Criteria
       2.  Application of Biological Criteria
    B.  History
       1.  Development of Biological Criteria
       2.  Current Status of Biological Criteria
    C.  Discussion
       1.  Program Resources
       2.  Program Evaluation

VII.  Case Study of Arkansas
    A.  Introduction
       1.  Derivation of Biological Criteria
       2.  Application of Biological Criteria
    B.  History
       1.  Development of Biological Criteria
       2.  Current Status of Biological Criteria
    C.  Discussion
       1.  Program Resources
       2.  Program Evaluation

VIII. Case Study of Florida
    A.  Introduction
       1.  Derivation of Biological Criteria
       2.  Application of Biological Criteria
    B.  History
    C.  Discussion

IX  Case Summaries of Six States
    A.  Connecticut
    B.  Delaware
    C.  Minnesota
    D.  Nebraska
    E.  New York
    F.  Vermont
                                        51

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                              Appendix  D
      Contributors  and Reviewers
Contributors
Gerald Ankley
USEPA Environmental Research
  Lab
6201 Congdon Blvd.
Duluth, MN 55804

John Arthur
USEPA
ERL-Duluth
6201 Congdon Blvd.
Duluth, MN 55804

Patricia Bailey
Division of Water Quality
Minnesota Pollution Control Agency
520 Lafayette Road
St. Paul, MN 55155

Joe Ball
Wisconsin DNR
Water Resource Management
  (WR/2)
P.O. Box 7291
Madison, Wl 53707

Michael Barbour
EA Engineering, Science, and
  Technology Inc.
Hunt Valley/Loveton Center
15 Loveton Circle
Sparks, MO 21152

Raymond Beaumler
Ohio EPA
Water Quality Laboratory
1030 King Avenue
Columbus, OH 43212
John Bender
Nebraska Department of
  Environmental Control
P.O. Box 94877
State House Station
Lincoln. NE 69509

Mark Blosser
Delaware Department of Natural
Resources - Water Quality Mgmt.
  Branch
P.O. Box 1401, 89 Kings Way
Dover. DE 19903

Robert Bode
New York State Department of
Environmental Conservation
Box 1397
Albany, NY 12201

Lee Bridges
Indiana Department of Environment
  Management
5500 W. Bradbury
Indianapolis, IN 46241

Claire Buchanan
Interstate Commission on Potomac
  River Basin
6110 Executive Boulevard Suite 300
Rockville, MD 20852-3903

David Courtemanch
Maine Department of
  Environmental Protection
Director, Division of Environmental
Evaluation and Lake Studies
State House No.  17
Augusta, ME 04333
Norm Crisp
Environmental Services Division
USEPA Region 7
25 Funston Road
Kansas City, KS 66115

Susan Davies
Maine Department of
  Environmental Protection
State House No. 17
Augusta, ME 04333

Wayne Davis
Environmental Scientist
Ambient Monitoring Section
USEPA Region 5
536 S. Clark St. (5-SMQA)
Chicago, IL 60605

Kenneth Duke
Battelle
505 King Avenue
Columbus, OH 43201-2693

Gary Fandrei
Minnesota Pollution Control Agency
Division of Water Quality
520 La Fayette Road North
St. Paul, MN 55155

Steve Flske
Vermont Department of
  Environmental Conservation
6 Baldwin Si
Montpelier, VT 05602
                                           53

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Biological Criteria: National Program Guidance
John Glese
Arkansas Department Of Pollution
  Control and Ecology
P.O. Box 9583
8001 National Drive
Little Rock, AR 72209

Steven Glomb
Office of Marine and Estuarine
  Protection
USEPA (WH-556F)
401 M Street SW
Washington, DC 20460

Steve Goodbred
Division of Ecological Services
U. S. Fish and Wildlife Service
1825 B. Virginia Street
Annapolis, MD 21401

Jim Harrison
USEPA Region 4
345 Courtland St. (4WM-MEB)
Atlanta, GA 30365

Margarete Heber
Office of Water Enforcements and
  Permits
USEPA (EN-336)
401 M Street SW
Washington, DC 20460

Steve Hedtke
US EPA Environmental Research
  Lab
6201 Congdon Blvd.
Duluth, MN  55804

Robert HIte
Illinois EPA
2209 West Main
Marion, IL 62959

Linda Hoist
USEPA Region 3
841 Chestnut Street
Philadelphia, PA 19107

Evan Hornlg
USEPA Region 6
Pirst Interstate Bank at Fountain
   Place
 1445 Ross Avenue, Suite 1200
Dallas, TX  75202
William B. Horning II
Aquatic Biologist, Project
  Management Branch
USEPA/ORD Env. Monitoring
  Systems
3411 Church St.
Cincinnati, OH *5244

Robert Hughes
NSI Technology Services
200 SW 35th Street
Corvallis, OR 97333

Jim Hulbert
Rorida Department of
  Environmental Regulation
Suite 232
3319MaguireBlvd.
Orlando, FL 32803

James Kennedy
Institute of Applied Sciences
North Texas State University
Denton, TX  76203

Richard Langdon
Vermont Department of
  Environmental
  Conservation—10 North
1038. Main Street
Waterbury.VT 05676

John Lyons
Special Projects Leader
Wisconsin Fish Research Section
Wisconsin Department of Natural
  Resources
3911 Fish Hatchery Rd.
Fitchburg, Wl 53711

Anthony Maclorowskl
Battelle
505 King Avenue
Columbus, OH 43201-2693

Suzanne Marcy
Office of Water Regulations and
  Standards
USEPA (WH 585)
401 M St. SW
Washington, DC 20460

Scon Matte*
Geological Survey of Alabama
PO Drawer 0
Tuscaloosa, AL 35486
John Maxted
Delaware Department of Natural
  Resources and Environmental
  Control
39 Kings Highway, P.O. Box 1401
Dover, DE 19903

Jimmie Overton
NC Dept of Natural Resources and
Community Development
P.O. Box 27687
512 N.Salisbury
Raleigh, NC 27611-7687

Steve Paulsen
Enviromental Research Center
University of Nevada - Las Vegas
4505 Maryland Parkey
Las Vegas, NV 89154

Loys Parrish
USEPA Region 8
P.O. Box 25366
Denver Federal Center
Denver, CO 80225

David Penrose
Environmental Biologist
North Carolina Department of
  Natural Resources and
Community Development
512 N.Salisbury Street
Raleigh, NC 27611

Don Phelps
USEPA
Environmental Research Lab
South Ferry Road
Narragansett, Rl 02882

Ernest Plzzuto
Connecticut Department
   Environmental Protection
122 Washington Street
Hartford, CT 06115

James Plafkln
Office of Water Regulations and
   Standards
USEPA (WH 553)
401 M Street, SW
Washington, DC 20460

Ronald Preston
Biological Science Coordinator
USEPA Region 3
Wheeling Office (3ES12)
303 Methodist Building
Wheeling, WV 26003
                                                  54

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                                                                      Appendix D: Contributors and Reviewers
Ronald Raschke
Ecological Support Branch
Environmental Services Division
USEPA Region 4
Athens, GA 30613

Mark Southerland
Oynamac Corporation
The Oynamac Building
11140RickvillePike
Rockville, MO 20852

James Thomas
Newfound .Harbor Marine Institute
Rt. 3, Box170
Big Pine Key, FL 33043

Nelson Thomas
USEPA, ERL-Duluth
Senior Advisor for National Program
6201 Congdon Blvd.
Duluth, MN 55804
Randall Walte
USEPA Region 3
Program Support Branch (3WMIO)
841 Chesnut Bldg.
Philadelphia, PA 19107

John Wegrzyn
Manager, Water Quality Standards
   Unit
Arizona Department of
   Environmental Quality
2005 North Central Avenue
Phoenix, AZ 95004

Thorn Whittler
NSI Technology Services
200 SW 35th Street
Corvallis, OR 97333

BUI Wuerthele
Water Management Division
USEPA Region 8 (WM-SP)
999 18th Street Suite 500
Denver, CO 80202
Chris Yoder
Asst. Manager, Surface Water
   Section
Water Quality Monitoring and
   Assessment
Ohio EPA-Water Quality Lab
1030 King Ave.
Columbus, OH 43212

David Yount
US EPA Environmental Research
   Lab
6201 Congdon Blvd.
Duluth, MN 55804

Lee Zenl
Interstate Commission on Potomac
   River Basin
6110 Executive Boulevard Suite 300
Rockville, MD 20852-3903
Reviewers
Paul Adamus
Wetlands Program
NSI Technology Services
200 S.W. 35th Street
Corvallis, OR 97333

Rick Albright
USEPA Region 10 (WD-139)
1200 6th Avenue NW
Seattle, WA 98101

Max Anderson
USEPA Region 5
536 S. Clark St. (5SCRL)
Chicago, IL 60605

Michael 0. Bllger
USEPA Region 1
John F. Kennedy Building
Boston, MA 02203

Susan Boldt
University of Wisconsin Extension
Madison, Wl

Paul Campanella
Office of Policy, Planning and
  Evaluation
USEPA (PM 222-A)
401 M St. S.W.
Washington, DC 20460
Cindy Carusone
New York Department of
  Environmental Conservation
Box1397
Albany, NY 12201

Brian Choy
Hawaii Department of Health
645 Halekauwila St.
Honolulu, HI 96813

Bill Creal
Michigan ONR
Surface Water Quality Division
P.O. Box 30028
Lansing, Ml 48909

Phil Crocker
Water Quality Management Branch
USEPA Region 6/1445 Ross Ave.
Dallas. TX 75202-2733

Kenneth Cummin*
Appalachian Environmental Lab
University of Maryland
Frostburg, M021532

JeffDeShon
Ohio EPA, Surface Water Section
1030 King Ave.
Columbus, OH 43212
Peter Farrlngton
Biomonitoring Assessments Officer
Water Quality Branch
Inland Waters Directorate
Environment Canada
Ottawa, Ontario K1A OH3

Kenneth Fenner
USEPA Region 5
Water Quality Branch
230 S. Dearborn
Chicago, IL 60604

Jack Freda
Ohio EPA
Surface Water Section
1030 King Avenue
Columbus. OH 43212

Toby Frevert
Illinois EPA
Division of Water Pollution Control
2200 Churchill Road
Springfield, IL 62706

Cynthia Fuller
USEPA GLNPO
230 S. Dearborn
Chicago. IL 60604
                                                 55

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Biological Criteria: National Program Guidance
Jeff Gagler
USEPA Region 5
230 S. Dearborn (5WQS)
Chicago, IL 60604

Mary Jo Garrels
Maryland Department of the
  Environment
2500 Broening Highway
Building 30
Baltimore, MD 21224

Jim Glattina
USEPA Region 5
230 S. Dearborn (5WQP)
Chicago, IL 60604

Jim Green
Environmental Services Division
USEPA Region 3
303 Methodist Bldg.
11th and Chapline
Wheeling, WV 26003

Larlndo Gronner
USEPA Region 4
345 Courtland St.
Atlanta, GA 30365

Martin Gurtz
U.S. Geological Survey, WRD
P.O. Box 2857
Raleigh, NC 27602-2857

Rick Hafele
Oregon Department  Environmental
  Quality
1712S.W. 11th  Street
Portland, OR 97201

Steve Helskary
MN Pollution Control Agency
520 Lafayette Road
St. Paul, MN 55155

Rollie Hemmett
USEPA Region  2
Environmental Services
Woodridge Avenue
Edison, NJ 08837

Charles Hocutt
Horn Point Environmental
  Laboratory
Box 775 University of Maryland
Cambridge, MD 21613
Hoke Howard
USEPA Region 4
College Station Road
Athens, GA 30605

Peter Husby
USEPA Region 9
215FreemontSt
San Francisco, CA94105

Gerald Jacob!
Environmental Sciences
School of Science and Technology
New Mexico Highlands University
Las Vegas, NM 87701

James Karr
Department of Biology
Virginia Polytechnic Institute and
  State University
Blacksburg, VA 24061-0406

Roy Kleinsasser
Texas Parks and Wildlife
P.O. Box 947
San Marcos, TX 78667

Don Kiemm
USEPA Environmental Monitoring
  and Systems Laboratory
Cincinnati, OH 45268

Robin Knox
Louisiana Department of
  Environment Quality
P.O. Box 44091
Baton Rouge, LA 70726

Robert Koroncai
Water Management Division
USEPA Region 3
847 Chestnut Bldg.
Philadelphia, PA 19107

Jim Kurztenbach
USEPA Region 2
Woodbridge Ave.
Rariton Depot Bldg. 10
Edison, NJ 08837

Roy Kwiatkowski
Water Quality Objectives Division
Water Quality Branch
Environment Canada
Ottawa, Ontario Canada
K1AOH3
Jim Lajorchak
EMSL-Cincinnati
U.S. Environmental Protection
  Agency
Cincinnati, OH

David Lenat
NC Dept of Natural Resources and
Community Development
512 N.Salisbury St.
Raleigh, NC 27611

James Luey
USEPA Region 5
230 S. Dearborn (5WQS)
Chicago, IL 60604

Terry Maret
Nebraska Department of
  Environmental Control
Box 94877
State House Station
Lincoln, NE  69509

Wally Matsunaga
Illinois EPA
1701 First Ave., #600
Maywood, IL60153

Robert Mosher
Illinois EPA
2200 Churchill Rd. #15
P.O. Box19276
Springfield,  IL 62794

Phillip Oshida
USEPA Region 9
215 Fremont Street
San Francisco, CA94105

Bill Painter
USEPA. OPPE
401 M Street, SW (W435B)
Washington, DC 20460

Rob Pepln
USEPA Region 5
230 S. Dearborn
Chicago, IL 60604

Wayne Poppe
Tennessee Valley Authority
270 Haney Bldg.
Chattanooga, TN 37401

Walter Redmon
USEPA Region 5
230 S. Dearborn
Chicago, IL 60604
                                                  56

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                                                                        Appendix D: Contributors and Reviewers
Landon Ross
Florida Department of
  Environmental Regulation
2600 Blair Stone Road
Tallahassee, FL 32399

Jean Roberts
Arizona Department of
  Environmental Quality
2655 East Magnolia
Phoenix, AZ 85034

Charles Saylor
Tennessee Valley Authority
Field Operations Eastern Area
Division of Services and Field
Operations
Norris, TN 37828

Robert Schacht
Illinois EPA
1701 First Avenue
Maywood, IL60153

Ouane Schuettpelz
Chief, Surface Water Standards and
Monitoring Section-Wisconsin
  Department of Natural
  Resources
Box 7921
Madison, Wl 53707
Bruce Shackleford
Arkansas Department of Pollution
  Control and Ecology
8001 National Drive
Little Rock, AR 72209

Larry Shepard
USEPA Region 5
230 S. Dearborn (5WQP)
Chicago, IL 60604

Jerry Shulte
Ohio River Sanitation Commission
49 E. 4th St., Suite 851
Cincinnati, OH 45202

Thomas Simon
USEPA Region 5
536 S. Clark St. (5SCRL)
Chicago, IL 60605

J. Singh
USEPA Region 5
536 Clark St. (5SCDO)
Chicago, IL 60605
Marc Smith
Biomonitoring Section
Ohio EPA
1030 King Avenue
Columbus, OH 43212

Denlse Steurer
USEPA Region 5
230 S. Dearborn
Chicago, IL 60604

William Tucker
Supervisor, Water Quality
  Monitoring
Illinois EPA
Division of Water Pollution Control
4500 S. Sixth Street
Springfield, IL 62706

Stephen Twldwell
Texas Water Commission
P.O. Box13087
Capital Station
Austin, TX 78711-3087

Barbara Williams
USEPA Region 5
230 S. Dearborn
Chicago, IL 60604
                                                  57

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         APPENDIX D
          National Guidance:
         Water Quality Standards
            for Wetlands
WATER QUALITY STANDARDS HANDBOOK

          SECOND EDITION

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          United States
          Environmental Protection
          Agency
              Office of Water
              Regulations and Standards (WH-585)
              Washinton, DC 20460
EPA440/S-90-011
July 1990
vEPA
Water  Quality Standards
for Wetlands

National Guidance

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WATER QUALITY STANDARDS FOR
               WETLANDS

               National Guidance
                   July 1990
                  Prepared by:

         U.S. Environmental Protection Agency
       Office of Water Regulations and Standards
            Office of Wetlands Protection

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  This document is designated as Appendix B to Chapter 2 - General Program Guidance of the Water Quality
Standards Handbook, December 1983.
            Table    of  Contents

                                                                    Page
 Transmittal Memo	 v
 Executive Summary	vii
 1.0 INTRODUCTION	1
    1.1 Objectives	2
    1.2 Organization	2
    1.3 Legal Authority	,	3
 2.0 INCLUSION OF WETLANDS IN THE DEFINITION OF STATE WATERS	5
 3.0 USE CLASSIFICATION	7
    3.1 Wetland Types	8
    3.2 Wetland Functions and Values	10
    3.3 Designating Wetland Uses	11
 4.0 CRITERIA	15
    4.1 Narrative Criteria	15
       4.1.1 General Narrative Criteria	16
       4.1.2 Narrative Biological Criteria	16
    4.2 Numeric Criteria	17
       4.2.1 Numeric Criteria - Human Health	17
       4.2.2 Numeric Criteria - Aquatic Life	17
 5.0 ANTIDEGRADATION	19
    5.1 Protection of Existing Uses	19

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    5.2 Protection of High-Quality Wetlands	20

    5.3 Protection of Outstanding Wetlands	20

6.0 IMPLEMENTATION	23

    6.1 Section 401 Certification	 23

    6.2 Discharges to Wetlands	24

        6.2.1 Municipal Wastewater Treatment	24

        6.2.2 Stormwater Treatment	24

        6.2.3 Fills	25

        6.2.4 Nonpoint Source Assessment and Control	25

    6.3 Monitoring	25

    6.4 Mixing Zones and Variances	26

7.0 FUTURE DIRECTIONS	29

    7.1 Numeric Biological Criteria for Wetlands	 29

    7.2 Wildlife Criteria	30

    7.3 Wetlands Monitoring	30

References	31

Appendices

    A - Glossary	A-1

    B - Definition of "Waters of the U.S."	B-1

    C - Information on the Assessment of Wetland Functions and Values	C-1

    D - Regional Wetlands Coordinators
          U.S. Environmental Protection Agency
          U.S. Fish and Wildlife Service	D-1

    E - Example of State Certification Action  Involving Wetlands under CWA Section 401	E-1
                                               IV

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           UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
                         WASHINGTON. D.C. 20460
                                                        OFFICE OF
                                                         WATER
                               -WL 30/990
MEMORANDUM

SUBJECT:  Final Document: National Guidance on Water Quality
          Standards for Wetlands
FROM:     Martha G. Prothro , Director            , ,_
          Office of Water Regulations.-and Standards
          David G. Davis,
          Office of Wetlands Protection

TO:       Regional Water Division Directors
          Regional Environmental Services Division Directors
          Assistant Regional Administrator for Policy
           and Management, Region VII
          OW Office Directors
          State Water Quality Program Managers
          State Wetland Program Managers


     The following document entitled "National Guidance: Water
Quality Standards for Wetlands" provides guidance for meeting the
priority established in the FY 1991 Agency Operating Guidance to
develop water quality standards for wetlands during the FY 1991-
1993 triennium.  This document was developed jointly by the
Office of Water Regulations and Standards (OWRS) and the Office
of Wetlands Protection (OWP), and reflects the comments we
received on the February 1990 draft from EPA Headquarters and
Regional offices, EPA laboratories, and the States.

     By the end of FY 1993, the minimum requirements for States
are to include wetlands in the definition of "State waters",
establish beneficial uses for wetlands, adopt existing narrative
and numeric criteria for wetlands, adopt narrative biological
criteria for wetlands, and apply antidegradation policies to
wetlands.  Information in this document related to the
development of biological criteria has been coordinated with
recent guidance issued by OWRS; "Biological Criteria: National
Program Guidance for Surface Waters", dated April 1990.

     We are focusing on water quality standards for wetlands to
ensure that provisions of the Clean Water Act currently applied
to other surface waters are also being applied to wetlands.   The
document focuses on those elements of water quality standards

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that can be developed now using the overall structure of the
water quality standards program and existing information and data
sources related to wetlands.  Periodically, our offices will
provide additional information and support to the Regions and
States through workshops and additional documents.  We encourage
you to let us know your needs as you begin developing wetlands
standards.  If you have any questions concerning this document,
please contact us or have your staff contact Bob Shippen in OWRS
(FTS-475-7329) or Doreen Robb in OWP (FTS-245-3906).
Attachment
cc:  LaJuana Wilcher
     Robert Wayland
                                 VI

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     EXECUTIVE   SUMMARY
  Background
  This document provides program guidance to States on how to ensure effective application of water
quality standards (WQS) to wetlands. This guidance reflects the level of achievement EPA expects the States
to accomplish by the end of FY 1993, as defined in the Agency Operating Guidance, FY1991, Office of Water.
The basic requirements for applying State water quality standards to wetlands include the following:


   • Include wetlands in the definition of "State waters."
   • Designate uses for all wetlands.
   • Adopt aesthetic narrative criteria (the "free froms") and appropriate numeric criteria for wetlands.
   • Adopt narrative biological criteria for wetlands.
   • Apply the State's antidegradation policy and implementation methods to wetlands.


  Water quality standards for wetlands are  necessary to ensure that the provisions of the Clean Water Act
(CWA) applied to  other surface waters  are also applied to wetlands.  Although Federal regulations im-
plementing the CWA include wetlands in the definition of "waters of the U.S." and therefore require water
quality standards, a number of States have not developed WQS for wetlands and have not included wetlands
in their definitions of "State waters." Applying water quality standards to wetlands is part of an overall effort
to protect and enhance the Nation's wetland  resources and provides a regulatory basis for a variety of
programs to meet this goal.  Standards provide the foundation for a broad range of water quality manage-
ment activities including, but not limited to, monitoring under Section 305(b), permitting under Sections 402
and 404, water quality certification under Section 401, and the control of NFS pollution under Section 319.

  With the issuance of this guidance, EPA proposes a two- phased approach for the development of WQS
for wetlands.  Phase 1 activities presented in this guidance include the development of WQS elements for
wetlands based upon existing information and science to be implemented within the next triennium.  Phase
2 involves the further refinement of these basic elements using new science and program developments. The
development of WQS for all surface waters is an iterative process.

  Definition
  The first and most important step in applying water quality standards to wetlands is ensuring that wetlands
are legally included in the scope of States' water quality standards programs. States may accomplish this by
adopting a regulatory definition of "State waters" at least as inclusive as the Federal definition of "waters of
the U.S." and by adopting an appropriate definition for "wetlands." States may also need to remove or modify
regulatory language that explicitly or implicitly limits the authority of water quality standards over wetlands.

  Use Designation
  At a minimum, all wetlands must have uses designated that meet the goals of Section 101 (a)(2) of the CWA
by providing for the protection and propagation of fish, shellfish, and wildlife and for recreation in and on the
water, unless the results of a use attainability analysis (UAA) show that the CWA Section I01(a)(2) goals
cannot be achieved.  When designating uses for wetlands, States may choose to use their existing general
                                             VII

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and  water-specific classification systems, or they may set  up an entirely different  system for  wetlands
reflecting their unique functions.  Two basic pieces of information are useful in classifying wetland uses: (1)
the structural types of wetlands and (2) the functions  and values associated with such types of wetlands.
Generally, wetland functions directly relate to the physical, chemical, and  biological integrity of wetlands.
The protection of these functions through water quality standards also may be needed to attain the uses of
waters adjacent to, or downstream of, wetlands.

 Criteria
  The Water Quality Standards Regulation (40 CFR 131.11 (a)(1)) requires States to adopt criteria  sufficient
to protect designated uses that may include general statements (narrative) and specific numerical values
(i.e., concentrations of contaminants and water quality characteristics).  Most State water quality standards
already contain many criteria for various water types and designated use classes that  may be applicable to
wetlands.

  Narrative criteria are  particularly important  in wetlands, since many wetland impacts cannot be fully
addressed by numeric criteria.  Such impacts may result from  the discharge of chemicals for which  there are
no numeric criteria in State standards, nonpoint sources,  and activities that may affect the physical and/or
biological, rather than the chemical, aspects of water quality (e.g., discharge of dredged and fill material).
Narratives should be written to protect the most sensitive designated use and to support existing uses under
State antidegradation policies.  In addition to other narrative criteria, narrative biological criteria provide a
further basis for managing a broad range of activities that impact the biological integrity of wetlands and
other surface waters, particularly physical and  hydrologic modifications.  Narrative biological criteria are
general statements of attainable or attained conditions of biological integrity and water quality for a given use
designation. EPA has published national guidance on developing biological criteria for all surface waters.

  Numeric criteria are specific numeric values for chemical constituents,  physical parameters, or biological
conditions that are adopted in State standards.  Human health water quality criteria are based on the toxicity
of a contaminant  and the amount of the contaminant  consumed  through ingestion of water  and fish
regardless of the type of water.   Therefore, EPA's chemical-specific  human  health criteria are directly
applicable to wetlands.   EPA  also  develops chemical-specific numeric  criteria recommendations for the
protection of freshwater and saltwater aquatic life. The numeric aquatic life criteria, although not designed
specifically for wetlands, were designed to be protective of aquatic life and are generally applicable to most
wetland types.  An exception to this are pH-dependent criteria,  such as  ammonia and pentachlorophenol,
since wetland  pH may be outside the normal  range of 6.5-9.0.  As  in other waters,  natural water quality
characteristics in some wetlands may be outside the range established for  uses designated in State stand-
ards.  These water quality characteristics may  require the development of criteria  that reflect the natural
background conditions in a  specific wetland or wetland type.  Examples of some of the wetland charac-
teristics that may fall  into this category are dissolved oxygen,  pH, turbidity, color, and hydrogen sulfide.

 Antidegradation
  The antidegradation policies contained in all State standards provide a powerful tool for the protection of
wetlands and can be used by  States to regulate point and nonpoint source discharges to wetlands  in the
same way as other surface waters.  In conjunction with beneficial uses and narrative criteria, antidegradation
can be used to address impacts to wetlands that cannot be  fully addressed by chemical criteria, such as
physical and  hydrologic modifications.  With  the inclusion  of wetlands as "waters  of the State," State
antidegradation policies and their implementation methods will apply to wetlands in the same way as other
surface waters.  State antidegradation policies should provide for the protection of existing uses in  wetlands
and the level  of  water quality necessary to protect those uses in the same manner as provided  for other
surface waters; see Section 131.12(a)(1) of the WQS regulation. In the case of fills, EPA interprets protection
of existing uses to be met if there is no significant degradation as defined according to the Section 404(b)(1)
guidelines.  State antidegradation policies also provide special protection for outstanding natural  resource
waters.
                                                Wll

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  Implementation
  Implementing water quality standards for wetlands will require a coordinated effort  between related
Federal and State agencies and programs. Many States have begun to make more use of CWA Section 401
certification to manage certain activities that impact their wetland resources on a physical and/or biological
basis rather than just  chemical impacts.  Section 401  gives the  States the authority  to grant,  deny,  or
condition certification of Federal permits or licenses that may result in a discharge to "waters of the U.S."
Such action is taken by the State to ensure compliance with various provisions of the CWA, including the
State's  water quality standards.  Violation of water quality standards is  often the basis  for denials  or
conditioning through Section 401 certification.

  Natural wetlands are nearly always "waters of the U.S." and are afforded the same level of protection  as
other surface waters with regard to standards and  minimum wastewater treatment requirements.  Water
quality standards for wetlands can prevent the misuse and overuse of natural wetlands for treatment through
adoption of proper uses and criteria and application of State antidegradation policies.  The Water Quality
Standards Regulation (40 CFR 131.10(a)) states that, "in no case shall a State adopt waste transport or waste
assimilation as  a designated use for any 'waters of the U.S.'." Certain activities involving the discharge  of
pollutants to wetlands may be  permitted; however,  as with other  surface waters, the State must ensure,
through ambient monitoring, that permitted discharges to wetlands preserve and protect wetland functions
and  values as defined in State  water quality standards.  For municipal discharges to natural wetlands, a
minimum  of secondary treatment is required,  and applicable water quality standards for the wetland and
adjacent waters must be met.   EPA anticipates that the policy for stormwater discharges to wetlands will
have some similarities to the policies for municipal wastewater discharges to wetlands.

  Many wetlands, through their assimilative capacity for nutrients and sediment,  also serve an important
water quality control function for nonpoint source pollution effects on waters adjacent to, or downstream of,
the wetlands.  Section 319 of the CWA  requires the States to complete assessments of nonpoint source
(NPS) impacts to State waters,  including wetlands, and  to prepare management programs to control  NPS
impacts. Water quality standards for wetlands can form the basis for these assessments and management
programs for wetlands.

  In addition, States can address physical and hydrological impacts on wetland quality through the applica-
tion  of narrative criteria to protect existing uses and through application of their antidegradation policies.
The  States should provide a  linkage in  their water quality standards to the  determination  of  "significant
degradation" as required under EPA guidelines (40  CFR 230.10(c)) and other applicable State laws affecting
the disposal of dredged or fill materials in wetlands.

  Finally,  water quality management  activities, including  the permitting  of  wastewater  and stormwater
discharges,  the assessment and control  of NPS pollution, and waste disposal activities (sewage sludge,
CERCLA, RCRA) require sufficient monitoring to ensure that the designated and existing uses of "waters  of
the U.S." are maintained and protected.  The inclusion of wetlands in water quality standards provides the
basis for conducting both wetland-specific  and status and trend monitoring of State wetland resources.
Monitoring of activities impacting specific wetlands may include several approaches, including biological
measurements  (i.e., plant, macroinvertebrate, and fish), that have  shown promise for  monitoring stream
quality.  The States are encouraged to develop and test the use of biological indicators.

  Future Directions
  Development of narrative biological  criteria  are  included in the first phase of the development of water
quality standards for wetlands.  The second phase involves the implementation of numeric biological criteria.
This  effort requires the detailed evaluation of the  components of  wetland  communities to  determine the
structure and function of unimpaired wetlands.  Wetlands are important habitats for wildlife species.  It  is
therefore also important to consider wildlife in developing criteria that protect the functions and values  of

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wetlands.  During the next 3 years, the Office of Water Regulations and Standards is reviewing aquatic life
water quality criteria to determine whether adjustments in the criteria and/or alternative forms of criteria (e.g.,
tissue concentration criteria) are needed to adequately protect wildlife species using wetland  resources.
EPA's Office of Water Regulations  and Standards is also developing guidance for EPA and State surface
water monitoring programs that will be issued by the end of FY 1990.  Other technical guidance and support
for the development of State water quality standards will be forthcoming from EPA in the next triennium.

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                                 Chapter 1J
                        Introduction
        Our understanding of the many benefits that
        wetlands provide has evolved rapidly over
        the last  20 to 30 years.  Recently,
programs  have been developed to restore and
protect wetland resources at the local, State, and
Federal levels of government. At the Federal level,
the President of the United States established the
goal of "no net loss" of wetlands, adapted from the
National Wetlands Policy Forum recommendations
(The Conservation Foundation 1988).  Applying
water  quality standards to wetlands is part  of an
overall effort to protect the Nation's wetland resour-
ces and provides a regulatory basis for a variety of
programs for managing wetlands to meet this goal.

  As the link between land and water, wetlands play
a vital role  in water quality management programs.
Wetlands provide a wide array of functions including
shoreline stabilization, nonpoint source runoff filtra-
tion, and erosion control, which directly benefit ad-
jacent and downstream waters.  In  addition, wet-
lands provide important biological habitat, including
nursery areas for aquatic life and wildlife, and other
benefits such as groundwater recharge and recrea-
tion.  Wetlands comprise a wide variety  of aquatic
vegetated systems including,  but not limited  to,
sloughs, prairie potholes, wet meadows, bogs, fens,
vernal pools, and marshes. The basic elements of
water quality standards (WQS), including desig-
nated uses,  criteria, and an antidegradation policy,
provide a sound legal basis for protecting wetland
resources through State water quality management
programs.

  Water quality standards  traditionally have been
applied to waters  such  as  rivers, lakes, estuaries,
and oceans, and have been applied tangentially, if at
all, to wetlands by applying the same uses and
criteria to wetlands as to adjacent perennial waters.
Isolated wetlands not directly associated with peren-
nial waters generally have  not  been addressed in
State water  quality standards.  A recent review of
State water quality standards (USEPA 1989d) shows
that only half of the States specifically refer to wet-
lands, or use similar terminology, in their water
quality standards.  Even where wetlands are refer-

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 enced, standards may not be tailored to reflect the
 unique characteristics of wetlands.

   Water quality standards specifically tailored to
 wetlands provide a consistent basis for the develop-
 ment of policies  and technical procedures for
 managing  activities  that impact wetlands.  Such
 water quality  standards provide  the  goals for
 Federal and State  programs that regulate  dischar-
 ges to wetlands, particularly those under CWA Sec-
 tions 402  and 404  as  well  as other regulatory
 programs (e.g., Sections 307, 318, and 405) and
 nonregulatory programs (e.g., Sections 314,  319,
 and 320).  In addition, standards play a critical role
 in the State 401 certification process by providing
 the basis for approving,  conditioning, or  denying
 Federal permits and licenses, as appropriate. Final-
 ly, standards provide a benchmark against which to
 assess the many activities that impact wetlands.

 1.1   Objectives

  The objective of this document is to assist States
 in applying  their water quality standards regulations
to wetlands in accordance with the Agency Operat-
ing Guidance (USEPA 1990a), which states:

   By September 30,  1993, States and qualified
   Indian  Tribes must adopt narrative water
   quality standards  that apply directly to  wet-
   lands. Those Standards shall be established
   in  accordance  with either  the National
   Guidance. Water Quality Standards for  Wet-
   lands... or some other scientifically valid
   method.  In adopting water quality standards
   for wetlands, States and qualified Indian
   Tribes, at a minimum, shall:  (1) define  wet-
   lands as  "State  waters";  (2) designate uses
   that protect the structure and function of wet-
   lands; (3)  adopt aesthetic narrative criteria
   (the "free froms")  and appropriate  numeric
   criteria in the standards to protect the desig-
   nated  uses;  (4) adopt narrative biological
   criteria in the standards; and (5)  extend the
   antidegradation  policy and implementation
   methods to wetlands.  Unless results of a use
  attainability analysis show that the section
   101 (a) goals  cannot be achieved,  States and
   qualified Indian  Tribes shall designate uses
  for wetlands that provide for the protection of
  fish, shellfish, wildlife, and recreation.  When
  extending the antidegradation policy and im-
    plementation methods to wetlands, con-
    sideration should be given to  designating
    critical wetlands as Outstanding National
    Resource Waters.   As necessary,  the  an-
    tidegradation policy should be revised to
    reflect the unique characteristics of wetlands.

   This level of achievement is based upon existing
 science and information, and therefore can be com-
 pleted within the FY 91-93 triennial review cycle.

   Initial development of water quality standards for
 wetlands over the next 3 years will provide the foun-
 dation for the development of more detailed water
 quality standards for wetlands in the future based on
 further research and policy development (see Chap-
 ter 7.0.).   Activities defined in this guidance  are
 referred to as "Phase 1 activities," while those to be
 developed over the longer term are referred  to as
 "Phase 2 activities." Developing water quality stand-
 ards is an iterative process.

   This guidance is not regulatory, nor is it designed
 to dictate specific approaches needed in State water
 quality standards.  The  document  addresses the
 minimum  requirements set out in  the  Operating
 Guidance,  and should  be used as  a  guide to the
 modifications  that may be needed in  State stand-
 ards.  EPA recognizes that State water quality stand-
 ards regulations vary greatly from State to State, as
 do wetland resources.  This guidance suggests ap-
 proaches that States may wish to use and allows for
 State flexibility and innovation.

 1.2  Organization

   Each chapter of this document provides guidance
 on a particular element of Phase 1  wetland  water
 quality standards that EPA expects States to under-
 take during the next triennial review  period (i.e., by
 September 30, 1993).  For each chapter, a discus-
 sion of what EPA considers to be minimally accept-
 able is followed by subsections providing informa-
 tion that may be used to meet, and go beyond, the
 minimum requirements during Phase 1. Documents
 referenced in this guidance provide further informa-
tion on specific topics and may be obtained from the
 sources listed  in the "References" section. The fol-
lowing paragraphs introduce each of the chapters of
this guidance.

  Most wetlands fall within the  definition  of "waters
of the U.S." and thus require water quality  stand-

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ards.  EPA expects States by the end of FY 1993 to
include wetlands in their definition of "State waters"
consistent with the Federal definition of "waters of
the U.S."  Guidance on the inclusion of wetlands in
the definition of "State waters" is contained in Chap-
ter 2.0.

  The application of water quality standards to wet-
lands requires that States designate appropriate
uses  consistent with Sections  I01(a)(2) and
303(c)(2) of the Clean Water  Act (CWA). EPA ex-
pects States by the end of FY 1993 to establish
designated  uses  for all wetlands.  Discussion of
designated uses is contained in Chapter 3.0.

  The WQS  regulation (40 CFR 131) requires States
to adopt water quality criteria sufficient to protect
designated uses.  EPA expects the States, by the
end of FY 1993, to adopt aesthetic narrative criteria
(the "free froms"), appropriate numeric criteria, and
narrative biological criteria for wetlands. Narrative
criteria are particularly important for wetlands, since
many activities may impact upon the physical and
biological, as well  as chemical, components of
water quality. Chapter 4.0 discusses the application
of narrative and numeric criteria to wetlands.

  EPA also expects  States to fully apply  an-
tidegradation policies and implementation methods
to wetlands by the end of FY 1993. Antidegradation
can provide a powerful tool  for the protection of
wetlands, especially through the requirement for full
protection of existing uses as well  as the  States'
option  of designating  wetlands  as outstanding na-
tional resource waters.  Guidance on the application
of State antidegradation policies to wetlands is con-
tained in Chapter 5.0.

  Many State  water quality standards contain
policies affecting  the  application and  implementa-
tion of water quality standards (e.g., variances,
mixing zones).  Unless otherwise  specified, such
policies are  presumed  to apply to wetlands in the
same manner as to other waters of the State. States
should consider whether such  policies should be
modified to  reflect the characteristics  of wetlands.
Guidance  on the implementation of water  quality
standards  for wetlands is contained in Chapter 6.0.

  Application of standards  to wetlands will be an
iterative process; both EPA and the States will refine
their approach based on new scientific information
as well as experience developed  through State
programs.  Chapter 7.0 outlines Phase 2 wetland
standards activities for which EPA is planning addi-
tional research and program development.

1.3  Legal Authority

  The Clean Water Act requires  States to develop
water quality standards, which include designated
uses and  criteria to support  those uses,  for
"navigable  waters."  CWA  Section  502(7) defines
"navigable waters" as "waters of the U.S." "Waters of
the U.S." are, in turn, defined in Federal regulations
developed for  the National Pollution Discharge
Elimination System (40 CFR 122.2) and permits for
the discharge of dredged or fill  material (40  CFR
230.3 and  232.2).   "Waters of the U.S." include
waters subject to the ebb and flow of the tide; inter-
state waters (including interstate wetlands) and in-
trastate waters (including wetlands),  the  use,
destruction, or  degradation of which  could affect
interstate commerce; tributaries of the above; and
wetlands adjacent  to the above waters (other  than
waters which are themselves waters). See Appendix
B for a complete definition.

   The  term  "wetlands"  is defined in 40 CFR
   232.2(r)  as:

   Those areas that are inundated or  saturated
   by surface or ground water at a frequency
   and  duration sufficient to support, and that
   under normal circumstances  do support,  a
   prevalence of vegetation typically adapted for
   life in saturated soil conditions.   Wetlands
   generally include swamps, marshes,  bogs,
   and similar areas.

  This definition of "waters of the U.S.," which in-
cludes, most wetlands, has been debated in Con-
gress and upheld by the courts. In 1977, a proposal
to delete CWA jurisdiction  over most  wetlands for
the purpose of the  Section 404 permit program was
defeated in the Senate.  The debate on the amend-
ment shows a strong congressional awareness  of
the value of wetlands and the importance of retain-
ing them  under the statutory scheme.   Various
courts have also upheld the application of the CWA
to wetlands.  See,  e.g., United States  v. Riverside
Bayview Homes, 474 U.S. 121 (1985); United States
v.  Byrd, 609  F.2d  1204 (7th Cir. 1979); Avoyelles
Sportsmen's League v. Marsh, 715 F.2d 897  (5th

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Cir.  1983); United States v.  Les//e Salt [1990
decision]. The practical effect is to make nearly all
wetlands "waters of the U.S."

  Created  wastewater treatment wetlands1
designed, built, and operated solely as wastewater
treatment systems are  generally not considered to
be waters of the U.S.  Water quality standards that
apply to natural wetlands generally do not apply to
such created wastewater treatment wetlands.  Many
created wetlands, however, are designed,  built, and
operated to provide, in addition to wastewater treat-
ment, functions and values similar to those provided
by natural wetlands.  Under certain circumstances,
such  created multiple  use wetlands  may be con-
sidered waters of the U.S. and as such would require
water quality standards. This determination must be
made on a case-by-case basis, and may consider
factors such as the size and degree of isolation of
the created wetlands and other appropriate factors.
    Different offices within EPA use different terminology (e.g., "create" or "constructed") to describe
    wastewater treatment wetlands. This terminology is evolving; for purposes of this guidance
    document,  the terms are interchangeable in meaning.

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                          Chapter 2.1
    Inclusion  of Wetlands  in
       the Definition  of State
                          Waters
      The first, and most important, step in apply-
      ing water quality standards to wetlands is
      ensuring that wetlands are legally included
in the scope of States' water quality standards
programs.  EPA expects States' water quality stand-
ards to include wetlands in the definition of "State
waters" by the end of FY 1993.  States may ac-
complish this by adopting a regulatory definition of
"State waters" at least as inclusive as the Federal
definition of "waters of the U.S." and by adopting an
appropriate definition for "wetlands." For example,
one State includes the following definitions in  their
water quality standards:

  "Surface waters of the State"... means all
  streams,... lakes..., ponds, marshes,  wet-
  lands or other waterways...

  "Wetlands" means areas of land where the
  water table is at, near or above the land sur-
  face long enough each year to result in the
  formation of characteristically wet (hydric)
  soil types, and support the growth of water
  dependent (hydrophytic) vegetation. Wet-
  lands include, but are not limited to, marshes,
  swamps, bogs, and other such low-lying
  areas.

  States may also need to remove or modify
regulatory language that explicitly or implicitly limits
the authority of water quality standards over wet-
lands. In certain  instances, such as when water

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quality standards are statutory or where a statute
defines or limits regulatory authority over wetlands,
statutory changes may be needed.

  The  CWA does not preclude States from adopt-
ing, under State law, a more expansive definition of
"waters of the State" to meet the goals  of the act.
Additional  areas that could be covered include
riparian areas, floodplains, vegetated buffer areas,
or any other critical areas identified by the State.
Riparian  areas  and floodplains are important and
severely threatened ecosystems, particularly in the
arid and  semiarid West.  Often it is technically dif-
ficult to separate, jurisdictionally, wetlands subject
to the provisions of the CWA from other areas within
the riparian or floodplain complex.

  States may  choose to include riparian or
floodplain ecosystems as a whole in the definition of
"waters of the State" or designate these areas for
special protection  in their water quality standards
through several  mechanisms, including definitions,
use classifications, and  antidegradation.  For ex-
ample, the regulatory  definition of "waters of the
State" in one State includes:

   ...The flood plain of free flowing waters deter-
   mined by the Department...on the basis of the
   100-year flood frequency.

  In another State, the definition of a use classifica-
tion states:

   This  beneficial use is  a combination of the
   characteristics of the watershed expressed in
   the water quality and the riparian area.

  And in a third State, the antidegradation protec-
tion for high-quality waters provides that:

   These waters shall  not  be lowered  in
   quality...unless it is determined by the com-
   mission that such lowering will not do any of
   the following:

     ...[bjecome injurious to  the value or
     utility of riparian lands...

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               Use    Classification
        At a minimum, EPA expects States by the
        end of FY 1993 to designate uses for all
        wetlands, and to meet the same minimum
requirements of the WQS regulation (40 CFR
131.10) that are applied to other waters.  Uses for
wetlands must meet the goals of Section 101(a)(2)
of the CWA by  providing for the protection and
propagation of fish, shellfish, and wildlife and for
recreation in and on the water, unless the results of
a use attainability analysis (UAA)  show that the CWA
Section 101(a)(2) goals cannot  be achieved.  The
Water Quality Standards Regulation (40 CFR
131.10(c))  allows for the designation of sub-
categories  of a  use, an activity that  may be ap-
propriate for wetlands.  Pursuant to the  WQS
Regulation  (40 CFR 131.10(i)), States must desig-
nate any uses that are presently being attained in
the wetland.  A technical support document is cur-
rently being developed by the Office of  Water
Regulations and  Standards for conducting use at-
tainability analyses for wetlands.

  The propagation of aquatic life and wildlife is an
attainable use in  virtually all wetlands. Aquatic life
protection need not refer only to year-round fish and
aquatic  life.  Wetlands often  provide valuable
seasonal habitat for fish and other aquatic life, am-
phibians, and  migratory bird reproduction  and
migration.  States  should ensure that aquatic life
and wildlife uses are designated for wetlands even if
a limited habitat is  available or the use is attained
only seasonally.

  Recreation in and on the water, on the other hand,
may not be attainable in certain wetlands that do not
have sufficient water, at least seasonally.  However,
States are also encouraged  to recognize  and
protect recreational uses that do not directly involve
contact  with water,  e.g.,  hiking, camping, bird
watching.

  The WQS regulation requires a UAA wherever a
State designates a use  that does not include the
uses specified in Section  101(a)(2) of the CWA; see
40 CFR Part 131.10(j). This need not bean onerous
task for States when deciding  whether certain
recreational uses are  attainable.  States may con-
duct generic UAAs for entire classes or types of

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wetlands based on the demonstrations in 40 CFR
Part 13l.10(g)(2).  States must, however, designate
CWA goal uses wherever these are attainable, even
where attainment may be seasonal.

  When designating uses for wetlands, States may
choose to use their existing general and water-
specific classification systems, or they may set up
an entirely different system for wetlands.  Each of
these  approaches has advantages and disad-
vantages, as discussed below.

  Some  States stipulate that wetlands are desig-
nated for the  same uses as the  adjacent waters.
States  may also apply their existing general clas-
sification system to designate uses for specific wet-
lands or groups of wetlands.   The  advantage of
these approaches is that they do not require States
to expend additional effort to develop specific wet-
land uses, or determine specific functions and
values, and can be generally used to designate the
CWA goal uses for wetlands.  However,  since wet-
land attributes may be  significantly  different than
those of other waters, States with general wetland
use designations will need to  review the uses for
individual wetlands in more detail when assessing
activities that may impair the specific "existing uses"
(e.g., functions and values).  In addition,  the "ad-
jacent" approach does not produce  uses  for "iso-
lated" wetlands.

  Owing to these differences in attributes, States
should strongly consider adopting a separate  use
classification system for wetlands based on wetland
type and/or beneficial use (function and value). This
approach initially requires more  effort in developing
use categories (and specific criteria that may be
needed for them),  as well as in determining what
uses to assign to  specific wetlands or  groups of
wetlands. The greater the specificity in designating
uses, however, the easier it  is for States to  justify
regulatory  controls to protect those uses.  States
may wish to designate beneficial uses for individual-
ly named wetlands, including outstanding wetlands
(see Section 6.3), although this approach may be
practical only for a limited number of wetlands.  For
the majority of their wetlands, States may wish to
designate generalized uses for groups of wetlands
based  on region or wetland type.

  Two basic  pieces of information are useful in
classifying wetland uses: (1) the structural types of
wetlands; and  (2) the functions and values as-
sociated with such types of wetlands.  The functions
and values  of wetlands  are  often defined based
upon structural type and  location  within  the
landscape or watershed.  The understanding of the
various wetland types within the State and  their
functions and values provides the basis for a com-
prehensive classification  system applicable to all
wetlands and all wetland uses. As with other waters,
both general and waterbody-specific classifications
may be needed to ensure  that uses are appropriate-
ly assigned to all wetlands in the State. Appropriate
and definitive use designations  allow water quality
standards to more accurately reflect both the "exist-
ing" uses  and the States' goals for  their  wetland
resources,  and to allow  standards to  be  a more
powerful tool in protecting State  wetlands. Sections
3.1 through  3.3 provide further information on wet-
land types, functions, and values,  and how these
can be used to designate  uses for wetlands.

3.1   Wetland Types
  A detailed understanding of the various  wetland
types within the State provides the basis for a com-
prehensive classification system. The classification
system most often cited  and  used  by Federal  and
State  wetland  permit programs  was  developed by
Cowardin et al. (1979) for the  U.S. Fish  and Wildlife
Service (FWS); see Figure 1.  This system provides
the basis  for wetland-related activities within the
FWS.  The Cowardin system is hierarchical and thus
can provide several  levels  of detail  in classifying
wetlands.  The "System" and  "Subsystem"  levels of
detail appear to be the  most promising for water
quality standards.  The "Class" level may be useful
for designating uses for specific wetlands or wetland
types. Section 3.3 gives an  example of how  one
State  uses the Cowardin  system to generate desig-
nated uses for wetlands.

  Under the Emergency Wetlands Resources Act of
1986, the FWS is required to complete the mapping
of wetlands within the lower 48 States  by  1998
through the National  Wetlands Inventory (NWI) and
to assess the status of the nation's wetland resour-
ces every  10 years.  The maps and status and trend
reports may help States  understand  the extent of
their wetlands and wetland types and  ensure that all
wetlands are assigned appropriate uses.   To date,
over 30,000 detailed 1:24,000 scale maps have been
completed,  covering approximately 60 percent of

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                                                   Subsystem
               i—Marine -
               —Estuarine-

X
a
I
£
a.
W
w
Q
a
z

i
         I
                                                  - Subtidal -
                                                   - Intertidal •
                                                   - Subtidal -
                                                   - Intertidal -
               — Riverine -
                                                   - Tidal -
                                                   -Lower Perennial -
                                                   -Upper Perennial -
                                                   -Intermittent •
                 - Lacustrine-
                                                   -Limnetic -
                                                   -Littoral-
                — Palustrine -
  Class

 -Rock Bottom
 -Unconsolidated Bottom
 -Aquatic Bed
 -Reef

 -Aquatic Bed
 -Reef
 -Rocky Shore
 -Unconsolidated Shore

 -Rock Bottom
 -Unconsolidated Bottom
 -Aquatic Bed
 -Reef

 - Aquatic Bed
 -Reef
 -Streambed
 - Rocky Shore
 -Unconsolidated Shore
 - Emergent Wetland
 -Scrub-Shrub Wetland
 - Forested Wetland

 - Rock Bottom
 - Unconsolidated Bottom
 - Aquatic Bed
 - Rocky Shore
 - Unconsolidated Shore
 - Emergent Wetland

 -Rock Bottom
 - Unconsolidated Bottom
 -Aquatic Bed
 —Rocky Shore
 -Unconsolidated Shore
 - Emergent Wetland

 - Rock Bottom
 -Unconsolidated Bottom
 -Aquatic Bed
 -Rocky Shore
 — Unconsolidated Shore
                                                                                     -Streambed
  ERock Bottom
  Unconsolidated Bottom
  Aquatic Bed
—Rock Bottom
—Unconsolidated Bottom
—Aquatic Bed
— Rocky Shore
— Unconsolidated Shore
— Emergent Wetland

— Rock Bottom
— Unconsolidated Bottom
—Aqua tic Bed
—Unconsolidated Shore
— Moss-Lichen Wetland
— Emergent Wetland
—Scrub-Shrub Wetland
L- Forested Wetland
                                  Figure 1.  Classification hierarchy of wetlands and
deepwater habitats, showing Systems, Subsystems, and Classes.  The Palustrine System does not include deepwater
                                         habitats (from Cowardin et al., 1979).

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the coterminous United States and  16 percent  of
Alaska2.

  In some States, wetland maps developed under
the NWI program have been digitized and are avail-
able for use with geographic information systems
(GIS).  To date, more than 5,700 wetland maps rep-
resenting 10.5 percent of the coterminous  United
States have  been  digitized.  Statewide digital
databases have  been developed for New Jersey,
Delaware, Illinois, Maryland,  and  Washington,  and
are in progress in Indiana and Virginia. NWI digital
data files also are available for portions of 20 other
States. NWI data files are sold at cost in 7.5-minute
quadrangle units.  The data are provided  on mag-
netic tape in MOSS export, DLG3 optional, ELAS,
and IGES formats3.  Digital wetlands data may ex-
pedite  assigning uses to wetlands for both general
and wetland-specific FIC classifications.

  The  classification of  wetlands may benefit from
the use of salinity concentrations.  The Cowardin
classification system uses a salinity criterion of 0.5
ppt ocean-derived salinity to differentiate  between
estuarine and freshwater wetlands.   Differences  in
salinity are reflected in  the species composition  of
plants and animals.  The use of salinity in the clas-
sification of wetlands may be useful  in restricting
activities that would alter the salinity of a wetland  to
such a degree  that the wetland type would change.
These activities include, for example, the construc-
tion of dikes to convert a saltwater marsh to a fresh-
water marsh or the dredging of channels that would
deliver saltwater to freshwater wetlands.
3.2  Wetland  Functions and
Values
  Many approaches have been developed for iden-
tifying wetland functions and values.   Wetland
evaluation techniques developed  prior to 1983 have
been  summarized  by  Lonard and Clairain (1985),
and  EPA   has   summarized  assessment
methodologies developed since 1983 (see Appendix
C).  EPA has also developed guidance on the selec-
tion of a methodology for activities under the Sec-
tion 404 program  entitled Draft  Guidance to  EPA
Regional Offices on the Use  of Advance Identifica-
tion Authorities Under Section 404 of the Clean
Water Act (USEPA 1989a). States may develop their
own techniques for assessing  the  functions  and
values of their wetlands.

  General  wetland functions that directly  relate to
the  physical,  chemical, and  biological integrity of
wetlands are listed below. The protection of these
functions through water quality standards also  may
be needed to attain the uses of waters adjacent to,
or downstream of, wetlands.
     Groundwater Recharge/Discharge
     Flood Flow Alteration
     Sediment Stabilization
     Sediment/Toxic Retention
     Nutrient Removal/Transformation
     Wildlife Diversity/Abundance
     Aquatic Diversity/Abundance
     Recreation
                                                    Methodologies that are  flexible with regard to
                                                 data  requirements and include several levels of
                                                 detail have the greatest potential for application to
                                                 standards. One such methodology is the Wetland
                                                 Evaluation Technique developed by Adamus, et al.
                                                 (1987) for the U.S. Army Corps of Engineers and the
    Information on the availability of draft and final maps may be obtained for the coterminous United
    States by calling 1-800-USA-MAPS or 703-860-6045 in Virginia.  In Alaska, the number is
    907-271-4159, and in Hawaii the number is 808-548-2861. Further information on the FWS National
    Wetlands Inventory (NWI) may be obtained from the FWS Regional Coordinators listed in Appendix D.

    For additional information on digital wetland data contact: USFWS; National Wetlands Inventory
    Program, 9720 Executive Center Drive, Monroe Building, Suite 101, St. Petersburg, FL 33702;
    813-893-3624, FTS 826-3624.
                                               10

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Department of Transportation. The Wetland Evalua-
tion Technique was designed for conducting an ini-
tial rapid assessment of wetland functions and
values in terms of social significance,  effectiveness,
and opportunity.  Social significance assesses the
value of a wetland to society in terms of its special
designation, potential economic value, and strategic
location. Effectiveness assesses the capability of a
wetland to perform a function because of its physi-
cal, chemical,  or biological characteristics. Oppor-
tunity assesses the [opportunity]  of  a wetland to
perform a function to its level of  capability.  This
assessment results in "high," "moderate," or "low"
ratings for 11  wetland functions in the context of
social significance, effectiveness,  and opportunity.
This technique also may be useful in identifying out-
standing wetlands for protection  under State  an-
tidegradation policies; see Section 5.3.

  The FWS maintains a Wetlands  Values Database
that also may be useful in identifying  wetland func-
tions and in designating wetland uses. The data are
keyed to the Cowardin-based wetland codes iden-
tified on the National Wetland Inventory maps. The
database  contains scientific literature on wetland
functions and values.  It is computerized and con-
tains over 18,000 citations,  of which  8,000 are  an-
notated.  For further information,  contact the NWI
Program (see Section 3.1) or the FWS National Ecol-
ogy Research  Center4.  In addition, State wetland
programs, EPA Regional wetland coordinators, and
FWS Regional wetland coordinators can provide in-
formation on wetland functions and values on  a
State or regional  basis; see Appendix D.
3.3  Designating Wetland Uses
  The functions and values of specifically identified
and  named wetlands, including  those identified
within the State's water-specific classification sys-
tem  and  outstanding  national  resource water
(ONRW) category, may be defined using the Wet-
land  Evaluation Technique or similar methodology.
For the general classification of wetlands, however,
States may choose to evaluate wetland function and
values for  all the wetlands within the State based on
wetland type (using Cowardin (1979); see Figure 1).
One  State applies its general use  classifications to
different wetland types based on Cowardin's system
level of detail as illustrated in  Figure 2. Note that the
State's uses are based on function, and the designa-
tion approach  links specific wetland functions to a
given wetland  type. The State evaluates wetlands
on a case-by-case basis  as individual permit
decisions  arise to ensure that designated uses are
being protected and have reflected existing uses.
    USFWS; Wetlands Values Database, National Ecology Research Center, 4512 McMurray, Ft. Collins,
    CO 80522; 303-226-9407.
                                               11

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                                              WETLAND  TYPE (Cowardinl
BENEFICIAL USE MARINE
Municipal and Domestic Supply
Agricultural Supply
Industrial Process Supply
Groundwater Recharge x
Freshwater Replenishment
Navigation x
Water Contact Recreation x
Non-Contact Water Recreation x
Ocean Commercial and Sport Fishing x
Warm Fresh Water Habitat
Cold Fresh Water Habitat
Preservation of Areas of Special
Biological Significance
Wildlife Habitat x
Preservation of Rare and Endangered x
Species
Marine Habitat x
Fish Migration x
Shellfish Harvesting x
Estuarine Habitat
ESTUARINE RIVERINE
x
X X
X 0
X X
X
X X
X X
X X
X
X
X
-
X X
X X
X
X X
X X
X
LACUSTRINE PALUSTRINE
X X
X X
o
X X
X X
X X
X X
X X
-
X X
X X
-
X X
X X
-
X
-
-
x = existing beneficial use
o = potential beneficial use
                           Figure 2. Example Existing and Potential Uses of Wetlands
                                                  12

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  Alternatively, a third method may use the location
of wetlands within the landscape as the  basis for
establishing general functions and values applicable
to all the wetlands within a defined region.  EPA has
developed a guidance entitled Regionalization as a
Tool  for Managing  Environmental Resources
(USEPA 1989c).  The  guidance illustrates how
various regionaiization techniques have been used
in water quality management, including the use of
the ecoregions developed by EPA's Office of Re-
search and Development, to direct State  water
quality standards and  monitoring programs.  These
approaches also may  be useful in the classification
of wetlands.

  EPA's Office of Research and Development is cur-
rently  refining a draft document that will provide
useful information to States related to use classifica-
tion methodologies (Adamus and Brandt - Draft).
There are likely many other approaches for desig-
nating uses for wetlands, and the  States are en-
couraged to develop  comprehensive classification
systems tailored to their wetland resources. As with
other  surface waters,  many wetlands are  currently
degraded by natural and anthropogenic activities.
The classification  of  wetlands  should  reflect the
potential uses attainable for a  particular wetland,
wetland type, or class  of wetland.
                                               13

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                                   Chapter  4.0
                                 Criteria
        The Water Quality Standards Regulation (40
        CFR 131.11(a)(1)) requires States to adopt
        criteria sufficient  to protect designated
uses.  These criteria may include general statements
(narrative) and specific numerical values (i.e., con-
centrations of contaminants and water quality char-
acteristics). At a minimum, EPA expects States to
apply aesthetic narrative criteria (the "free froms")
and appropriate numeric criteria to wetlands and to
adopt narrative biological criteria for wetlands by
the end of FY  1993. Most State water quality stand-
ards already contain many criteria for various water
types  and designated use classes, including narra-
tive criteria and numeric criteria to protect human
health and freshwater and saltwater aquatic life, that
may be applicable to wetlands.

  In many cases,  it may be necessary to use a com-
bination of numeric and narrative criteria to ensure
that wetland functions and values are  adequately
protected. Section 4.1 describes the application of
narrative criteria to wetlands and Section 4.2 discus-
ses application of numeric criteria for protection of
human health and aquatic life.
4.1   Narrative Criteria
  Narrative criteria are general statements designed
to protect a specific designated use or set of uses.
They can be statements prohibiting certain actions
or conditions  (e.g.,  "free from substances that
produce  undesirable  or nuisance aquatic life") or
positive statements about what is expected to occur
in the water (e.g., "water quality and aquatic life shall
be as it  naturally  occurs").  Narrative criteria are
used to identify impacts on designated uses and as
a regulatory basis for controlling a variety of impacts
to State waters.  Narrative criteria  are particularly
important in wetlands, since many wetland impacts
cannot be fully addressed by numeric criteria. Such
impacts may result from the discharge of chemicals
for which there are no numeric criteria  in State
standards, from nonpoint sources, and from ac-
tivities that may affect the physical and/or biological,
rather than the chemical,  aspects of  water quality
(e.g., discharge of dredged and fill material). The
Water  Quality  Standards Regulation  (40 CFR
131.11(b)) states that "States should...include narra-
                                              15

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tive criteria in their standards where numeric criteria
cannot be established or to supplement numeric
criteria."

  4.1.1  General Narrative Criteria
  Narrative criteria within the water  quality stand-
ards program date back to at least 1968 when five
"free froms" were included in  Wafer Quality Criteria
(the Green Book), (FWPCA 1968).   These  "free
froms" have been included as "aesthetic criteria" in
EPA's most recent Section 304(a) criteria summary
document, Quality Criteria for Water - 1986 (USEPA
1987a). The narrative criteria from these documents
state:

   All wafers [shall be] free from substances at-
   tributable to wastewater or other discharge
   that:

  (1)   settle to form objectionable deposits;

  (2)   float as debris, scum,  oil, or other matter to
       form nuisances;

  (3)   produce objectionable color, odor, taste, or
       turbidity;

  (4)   injure  or are toxic  or produce adverse
       physiological  responses  in humans,
       animals or plants; and

  (5)   produce  undesirable  or nuisance aquatic
       life.

  The Water Quality Standards Handbook (USEPA
1983b) recommends that States apply narrative
criteria to all waters of the United States. If these or
similar criteria are already applied to all State waters
in a State's standards,  the inclusion of wetlands in
the definition of "waters of the  State" will apply these
criteria to wetlands.

  4.1.2  Narrative Biological Criteria
  Narrative biological criteria  are  general  state-
ments of  attainable or attained conditions of biologi-
cal integrity and water quality for a given use desig-
nation. Narrative biological criteria can take a num-
ber of forms.  As a sixth "free  from," the criteria
could read "free  from activities that would substan-
tially impair the biological community as it naturally
occurs due to physical, chemical, and  hydrologic
changes," or the criteria may contain  positive state-
ments  about the  biological community  existing  or
attainable in wetlands.

  Narrative biological, criteria  should contain at-
tributes that support the goals  of the Clean Water
Act, which provide for the protection and propaga-
tion of fish, shellfish, and wildlife.  Therefore, narra-
tive criteria should include specific language about
community characteristics that  (1) must exist in a
wetland to meet a particular designated aquatic
life/wildlife use, and (2) are quantifiable. Supporting
statements for the criteria should promote water
quality to protect the most natural community as-
sociated with the designated  use.   Mechanisms
should be  established  in the standard to address
potentially conflicting  multiple uses.  Narratives
should  be written  to protect the most sensitive
designated use and to support existing uses under
State antidegradation policies.

  In addition to other narrative criteria, narrative
biological criteria provide a further basis for manag-
ing a broad range of activities that impact the
biological integrity  of wetlands and  other surface
waters,  particularly  physical and hydrologic
modifications. For instance, hydrologic criteria are
one particularly important but often overlooked
component to include in water quality standards  to
help maintain wetlands  quality.  Hydrology is the
primary factor influencing the type and location  of
wetlands.  Maintaining appropriate hydrologic con-
ditions in wetlands is critical to  the maintenance  of
wetland functions and values.  Hydrologic manipula-
tions to wetlands have occurred nationwide in the
form of flow alterations and diversions, disposal  of
dredged or fill material, dredging of canals through
wetlands, and construction of levees  or dikes.
Changes in base flow or flow regime can severely
alter the plant and  animal species composition of a
wetland, and destroy the entire wetland system if the
change is great enough. States should consider the
establishment of criteria to regulate  hydrologic al-
terations to wetlands.  One State has adopted the
following  language and criteria to  maintain and
protect the natural hydrologic  conditions  and values
of wetlands:

   Natural hydrological conditions necessary to
   support the biological and physical  charac-
   teristics naturally present in wetlands shall be
   protected to prevent significant adverse im-
   pacts on:
                                                16

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  (1)   Water currents, erosion or sedimentation
       patterns;

  (2)   Natural water temperature variations;

  (3)   The  chemical,  nutrie-nt  and dissolved
       oxygen regime of the wetland;

  (4)   The normal movement of aquatic fauna;

  (5)   The pH of the wetland; and

  (6)   Normal water levels or elevations.

  One source of information for developing more
quantifiable hydrologic criteria is the Instream Flow
Program of the U.S. Fish and Wildlife Service, which
can provide technical guidance on the minimum
flows necessary to attain various water uses.

  Narrative criteria, in conjunction with antidegrada-
tion policies, can provide the basis for determining
the impacts of activities (such  as hydrologic
modifications) on  designated  and existing uses.
EPA has published  national guidance on developing
biological criteria  for all surface waters (USEPA
1990b). EPA's Office of Research and Development
also has produced a literature synthesis of wetland
biomonitoring data on  a State-by-State basis, which
is intended to support  the development of narrative
biological  criteria (Adamus and Brandt - Draft).

4.2  Numeric Criteria
  Numeric criteria  are specific  numeric values for
chemical  constituents, physical parameters,  or
biological conditions that are adopted  in State
standards. These may  be values not to be exceeded
(e.g.,  toxics), values that must be exceeded (e.g.,
dissolved  oxygen), or a combination of the two
(e.g.,  pH).  As with all criteria,  numeric criteria are
adopted to protect one or more designated uses.
Under Section 304(a)  of the Clean Water Act, EPA
publishes  numeric national criteria recommenda-
tions  designed  to  protect aquatic organisms and
human  health.   These criteria are summarized in
Quality Criteria for Water  - 1986  (USEPA 1987a).
These criteria serve as guidelines from which States
can develop their own numeric  criteria, taking into
account the particular uses designated by the State.
  4.2.1  Numeric Criteria - Human
  Health
  Human health water quality criteria are based on
the toxicity of a contaminant and the amount of the
contaminant consumed through ingestion of water
and fish regardless of the type of water. Therefore,
EPA's chemical-specific human health criteria are
directly applicable to wetlands. A summary of EPA
human health criteria recommendations  is con-
tained in Quality Criteria for Water - 1986.

  Few wetlands are used directly for drinking water
supplies.  Where drinking water is a designated or
existing use for a  wetland  or for  adjacent waters
affected by the wetland, however, States must pro-
vide criteria sufficient to protect human health based
on water consumption  (as well as  aquatic life con-
sumption if appropriate).   When assessing the
potential for water consumption, States should also
evaluate the wetland's groundwater recharge func-
tion to assure  protection  of drinking water supplies
from that source as well.

  The application of human health criteria, based on
consumption of aquatic life, to wetlands is a function
of the level of detail in the States' designated  uses.
If all wetlands are designated  under the State's
general "aquatic life/wildlife" designation,  consump-
tion of that aquatic life is assumed to be an included
use and the State's human health criteria based on
consumption  of aquatic life  will apply throughout.
However,  States that adopt  a more detailed use
classification system for wetlands (or wish to derive
site-specific human health criteria for wetlands) may
wish to selectively apply human health  criteria to
those wetlands where consumption of aquatic life is
designated or likely to occur (note that a UAA will be
required where CWA goal uses are not designated).
States may also wish  to adjust the exposure as-
sumptions  used in deriving  human health  criteria.
Where it is known that exposure to individuals at a
certain site, or within a certain category of wetland,
is likely to be different from the assumed exposure
underlying  the States' criteria, States may wish to
consider a reasonable estimate of the actual  ex-
posure and take this estimate into  account  when
calculating the criteria for the site.

  4.2.2  Numeric Criteria - Aquatic Life
  EPA develops chemical-specific numeric criteria
recommendations for the protection of freshwater
                                               17

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and  saltwater aquatic life.  These criteria may be
divided into two  basic categories:   (1) chemicals
that  cause toxicity to aquatic life such as  metals,
ammonia,  chlorine,  and organics; and (2) other
water  quality characteristics such as dissolved
oxygen,  alkalinity, salinity, pH,  and temperature.
These  criteria are currently  applied directly to a
broad  range  of surface waters in State standards,
including lakes,  impoundments, ephemeral  and
perennial rivers and streams, estuaries,  the oceans,
and  in some instances, wetlands.  A summary of
EPA's aquatic life criteria recommendations is pub-
lished  in  Quality Criteria for Water -  1986.  The
numeric aquatic life criteria, although not designed
specifically for wetlands, were designed to be
protective of aquatic life and are generally ap-
plicable to most wetland types.

  EPA's aquatic life criteria  are  most often based
upon lexicological testing under controlled  condi-
tions in the laboratory.  The EPA guidelines for the
development  of such criteria (Stephan et al., 1985)
require the testing of plant, invertebrate, and fish
species.  Generally, these criteria are supported by
toxicity tests on invertebrate and early life stage fish
commonly found  in many wetlands. Adjustments
based  on natural  conditions,  water  chemistry,  and
biological community  conditions may  be ap-
propriate  for certain criteria  as  discussed below.
EPA's  Office  of Research and Development  is  cur-
rently finalizing a draft document that provides addi-
tional technical guidance on this topic, including
site-specific  adjustments of  criteria (Hagley  and
Taylor  - Draft).

  As in other waters, natural  water  quality charac-
teristics in some wetlands may be outside the range
established for uses designated in State standards.
These water quality characteristics may require the
development  of criteria that reflect the natural back-
ground conditions in a specific wetland  or wetland
type. States routinely set criteria for specific waters
based  on  natural conditions.  Examples of some of
the wetland characteristics that  may fall into this
category are dissolved oxygen, pH, turbidity, color,
and hydrogen sulfide.

  Many of EPA's  aquatic life  criteria are based on
equations that take into account salinity,  pH,
temperature and/or hardness. These may be directly
applied to wetlands in the same way as other water
types with adjustments in  the criteria to reflect these
water quality characteristics. However, two national
criteria that are pH dependent, ammonia and pen-
tachlorophenol, present a different situation.  The
pH in some wetlands may be outside the pH range
of 6.5-9.0 units for which these criteria were derived.
It  is recommended that States conduct additional
toxicity testing if they wish to derive criteria for am-
monia and  pentachlorophenol  outside the 6.5-9.0
pH range, unless data are already available.

   States may also develop scientifically defensible
site-specific criteria for parameters whose State-
wide values may be inappropriate.  Site-specific  ad-
justments may be made based on the water quality
and biological conditions in a specific water, or in
waters within a particular region or ecoregion. EPA
has developed guidance on the site-specific adjust-
ment of the national criteria (USEPA !983b). These
methods are applicable to wetlands and should be
used  in the same  manner as States use them  for
other waters.  As  defined in the Handbook,  three
procedures may be used to develop site-specific
criteria:   (1) the recalculation procedures, (2)  the
indicator species procedures, and (3) the resident:
species procedures.   These procedures may  be
used  to develop site-specific numeric criteria  for
specific wetlands or wetland types. The recalcula-
tion procedure is used  to make adjustments based
upon  differences between the  toxicity to resident
organisms and those used to derive national criteria.
The indicator species procedure is  used to account
for differences in the bioavailability and/or toxicity ol
a contaminant based upon the physical and chemi-
cal characteristics of site  water.  The  resident
species procedure accounts for differences in both
species sensitivity and water quality characteristics.
                                                18

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                 Antidegradation
       The antidegradation policies contained in all
       State standards provide a powerful tool for
       the protection of wetlands and can be used
by States to regulate point  and  nonpoint source
discharges to wetlands in the same way as other
surface waters.  In conjunction with beneficial uses
and narrative criteria, antidegradation can be used
to address impacts to wetlands that cannot be fully
addressed by chemical criteria, such as physical
and hydrologic  modifications. The implications of
antidegradation to the disposal of dredged and fill
material are discussed in Section 5.1 below.  At a
minimum, EPA  expects States to fully apply their
antidegradation policies and implementation
methods to wetlands by the  end of FY 1993.  No
changes to State policies  are required if they are
fully consistent  with  the Federal policy.  With the
inclusion of wetlands as "waters of the State," State
antidegradation  policies and their implementation
methods will apply to wetlands in the same way as
other surface waters.  The WQS  regulation
describes the requirements for State antidegrada-
tion policies, which include full protection of existing
uses  (functions  and values),  maintenance of water
quality in high-quality waters, and a prohibition
against lowering water quality in outstanding nation-
al resource waters. EPA guidance on the implemen-
tation of antidegradation policies is contained in the
Water Quality Standards Handbook (USEPA 1983b)
and Questions and Answers  on: Antidegradation
(USEPA 1985a).

5.1  Protection  of Existing Uses
  State antidegradation policies should provide for
the protection of existing uses in wetlands and the
level  of water quality necessary to protect those
uses in the same  manner as for other surface
waters; see Section I3l.l2(a)(1) of the WQS regula-
tion.   The existing use can  be determined by
demonstrating that the use or uses have actually
occurred since November 28, 1975, or that the water
quality is suitable to allow the  use to be attained.
This is the basis of EPA's antidegradation policy and
is important in the wetland protection effort.  States,
especially those that adopt less detailed use clas-
sifications for wetlands, will need to use the existing
use protection in their antidegradation policies to
ensure protection of wetland values and functions.
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  Determination of an existing aquatic  life and
wildlife use  may require  physical, chemical, and
biological  evaluations through a waterbody survey
and assessment.   Waterbody survey and assess-
ment guidance may be found in three volumes en-
titled Technical Support Manual for Conducting Use
Attainability Analyses (USEPA 1983b,  1984a,
1984b).  A technical support manual for conducting
use attainability analyses  for wetlands is currently
under development by the Office of Water Regula-
tions and Standards.

  In the case of wetland fills, EPA allows a slightly
different interpretation of existing uses under the
antidegradation policy. This interpretation has been
addressed in the answer to question no. 13 in Ques-
tions and Answers on: Antidegradation  (USEPA
1985a), and is presented below:

   Since  a  literal interpretation of the an-
   tidegradation policy could result in prevent-
   ing the issuance of any wetland fill permit
   under Section 404 of the Clean Water Act, and
   it is logical to assume that Congress intended
   some such permits to  be granted within the
   framework of the Act, EPA interprets 40 CFR
   131.12(a)(l) of the antidegradation policy to
   be satisfied with regard to fills in wetlands if
   the discharge did  not result in "significant
   degradation"  to the aquatic  ecosystem as
   defined under Section 230.10(c) of the Sec-
   tion 404(b)(l) guidelines.   If any wetlands
   were found to have better water quality than
   "fishable/swimmable," the State would be al-
   lowed to lower  water  quality to the no sig-
   nificant degradation level as long as the re-
   quirements of Section 131.12(a)(2) were fol-
   lowed.  As for  the ONRW  provision  of an-
   tidegradation  (131.12(a)(3)),  there is no dif-
   ference in the way it applies to wetlands and
   other waterbodies.

  The Section 404(b)(1)  Guidelines  state that the
following effects contribute to  significant degrada-
tion, either individually or collectively:

   ...significant adverse  effects on (1) human
   health or welfare, including effects on
   municipal water supplies,  plankton, fish,
   shellfish, wildlife, and special aquatic sites
   (e.g., wetlands); (2)  on the life  stages of
   aquatic life and other wildlife dependent on
   aquatic ecosystems, including the  transfer,
   concentration or spread of pollutants or their
   byproducts beyond the site through biologi-
   cal, physical, or chemical process; (3)  on
   ecosystem  diversity,  productivity and
   stability, including loss of fish and wildlife
   habitat or loss of the capacity of a wetland to
   assimilate nutrients,  purify water or reduce
   wave energy; or (4) on recreational, aes-
   thetic, and economic values.

  These Guidelines may be used by States to deter-
mine "significant degradation" for wetland fills.  Of
course, the States are free to adopt stricter require-
ments for wetland fills in their own antidegradation
policies, just as they may adopt any other require-
ments more stringent than Federal law requires. For
additional information on the linkage between water
quality standards and the Section 404 program, see
Section 6.2 of this guidance.

5.2  Protection of High-Quality
Wetlands
  State antidegradation policies  should provide for
water quality in  "high quality wetlands" to be main-
tained and  protected,  as prescribed in Section
131.12(a)(2) of the WQS regulation.  State  im-
plementation  methods requiring alternatives
analyses, social and economic justifications,  point
and nonpoint source control, and public participa-
tion are to be applied to wetlands in the same man-
ner they are applied to other surface waters.

5.3  Protection of Outstanding
Wetlands
  Outstanding  national  resource waters (ONRW)
designations offer special protection (i.e., no
degradation) for designated waters,  including  wet-
lands.  These are areas of exceptional water quality
or recreational/ecological significance.  State an-
tidegradation  policies should provide special
protection to wetlands  designated as  outstanding
national resource waters in the same  manner as
other surface waters; see Section 131.12(a)(3) of the
WQS regulation and EPA guidance Wafer Quality
Standards Handbook  (USEPA  1983b),  and  Ques-
tions and Answers on: Antidegradation (USEPA
1985a). Activities that might trigger a State analysis
of a wetland for possible designation as an ONRW
are no different  for wetlands than for  other waters.
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  The following list provides general information on
wetlands that are likely candidates for protection as
ONRWs.  It also may be used to identify specific
wetlands for use designation under the State's wet-
land classification system;  see Chapter 4.0.  Some
of these  information sources  are discussed in
greater detail in EPA's guidance entitled  Wetlands
and Section 401  Certification: Opportunities and
Guidelines for States and Eligible Indian Tribes
(USEPA 1989f); see Section 6.1.

    • Parks, wildlife management areas, refuges, wild
     and scenic rivers, and estuarine sanctuaries;

    • Wetlands adjacentto ONRWs or other high-quality
     waters (e.g., lakes, estuaries shellfish beds);

    • Priority wetlands identified under the Emergency
     Wetlands  Resources Act  of  1986 through
     Statewide Outdoor Recreation Plans (SORP) and
     Wetland Priority Conservation Plans;

    • Sites within joint venture project areas under the
     North American Waterfowl Management Plan;
   • Sites under the Ramsar (Iran) Treaty on Wetlands
     of International Importance;

   • Biosphere reserve sites identified as part of the
     "Man and the Biosphere" Program sponsored by
     the United Nations;

   • Natural heritage areas and other similar designa-
     tions established by the State or private organiza-
     tions (e.g., Nature Conservancy); and

   • Priority wetlands identified as part of comprehen-
     sive planning efforts conducted at the local, State,
     Regional, or Federal levels of government; e.g.,
     Advance Identification (ADID) program under Sec-
     tion 404 and Special Area Management Plans
     (SAMPs) under the 1980 Coastal Zone Manage-
     ment Act.

  The  Wetland Evaluation Technique;  Volume II:
Methodology (Adamus et al., 1987) provides addi-
tional guidance on the identification of wetlands with
high ecological and social value; see Section 3.2.
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                               Chapter
                 Implementation
     Implementing water quality standards for wet-
     lands will require a coordinated effort between
     related Federal and  State agencies and
programs. In addition to the Section 401 certifica-
tion for Federal permits and licenses, standards
have other potential applications for State
programs, including landfill siting, fish and wildlife
management and  aquisition decisions,  and best
management practices to control nonpoint source
pollution.  Many coastal States have wetland permit
programs, coastal zone management programs,
and National Estuary Programs; and the develop-
ment of water quality standards should utilize data,
information and expertise from these programs. For
all States, information and  expertise is available
nationwide from EPA and the Corps of Engineers as
part of the Federal 404 permit program.   State
wildlife and fisheries departments can also provide
data, advice, and expertise related  to wetlands.
Finally,  the FWS can provide information on wet-
lands as part of the National Wetlands  Inventory
program, the Fish and Wildlife Enhancement Pro-
gram, the Endangered Species and Habitat Conser-
vation Program,  the North American Waterfowl
Management Program and  the National Wildlife
Refuge program.  EPA and FWS wetland program
contacts are included in Appendix D.

  This section provides information on certain ele-
ments of standards (e.g., mixing zones) and the
relationship between wetland standards and other
water-related activities and programs (e.g., monitor-
ing and CWA Sections 401, 402, 404, and 319).  As
information is developed by EPA and the  States,
EPA will periodically transfer it nationwide through
workshops and program summaries.  EPA's Office
of Water Regulations and Standards has developed
an outreach program for providing this information.

6.1  Section 401 Certification

  Many States have begun to make more  use of
CWA Section 401 certification to manage  certain
activities that impact their wetland resources. Sec-
tion 401  gives the  States the authority to grant,
deny, or condition certification of Federal permits or
licenses (e.g., CWA  Section 404 permits issued by
the U.S. Army Corps of Engineers, Federal  Energy
                                         23

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Regulatory Commission licenses, some Rivers and
Harbors Act Sections 9 and  10  permits, and CWA
Section 402 permits where issued by EPA) that may
result in a discharge to "waters  of the U.S."  Such
action  is taken by the State to ensure compliance
with  various provisions of the CWA.  Violation of
water quality standards is often the basis for denials
or conditioning through Section 401 certification. In
the absence of wetland-specific standards,  States
have based decisions on their general  narrative
criteria and antidegradation policies. The Office of
Wetlands Protection has developed a handbook for
States  entitled Wetlands and 401 Certification: Op-
portunities and Guidelines for States and Eligible
Indian  Tribes (USEPA 1989g) on the use of Section
401 certification to protect wetlands.  This docu-
ment provides  several examples wherein  States
have applied their water quality standards  to wet-
lands; one example is included in Appendix E.

  The  development of explicit water quality stand-
ards for wetlands, including wetlands in the defini-
tion  of "State  waters,"  uses,  criteria, and an-
tidegradation policies, can provide a strong and
consistent basis for State 401  certifications.

6.2  Discharges to Wetlands
  The Water Quality Standards Regulation (40 CFR
I31.10(a)) states that, "in no case shall a State adopt
waste  transport  or waste assimilation as a desig-
nated use for any 'waters of the U.S.'." This prohibi-
tion extends to wetlands, since they are included in
the definition of "waters of the  U.S."  Certain ac-
tivities involving the discharge of pollutants to wet-
lands may be permitted, as with other water types,
providing a determination is  made that the desig-
nated  and existing  uses of the wetlands and
downstream  waters will  be  maintained and
protected.  As with other  surface waters, the State
must ensure, through ambient monitoring, that per-
mitted  discharges to wetlands preserve and  protect
wetland functions and values as  defined in State
water quality standards; see Section 6.4.

  Created wastewater treatment wetlands that are
not impounded from waters of the United States and
are designed,  built, and  operated solely as was-
tewater treatment systems, are a special case, and
are not generally considered "waters of  the U.S."
Some such created wetlands, however, also  provide
other functions and values similar to those provided
by natural wetlands.  Under certain circumstances,
such created,  multiple use wetlands may be con-
sidered "waters of the U.S.," and as such, would be
subject to the  same protection and restrictions on
use as natural  wetlands (see Report on the Use of
Wetlands for Municipal Wastewater Treatment and
Disposal (USEPA 1987b)). This determination must
be made on a case-by-case basis, and may consider
factors such as the size and degree of isolation of
the created wetland.

  6.2.1  Municipal Wastewater Treat-
  ment
  State  standards should be consistent with the
document developed by the Office of Municipal Pol-
lution Control  entitled Report on the Use of Wet-
lands for Municipal Wastewater Treatment and Dis-
posal (USEPA  1987b), on the use of wetlands for
municipal wastewater treatment.  This document
outlines minimum treatment and other requirements
under the CWA for discharges to natural wetlands
and those specifically created and used for the pur-
pose of wastewater treatment.

  The following is a brief summary of the above-ref-
erenced document.  For municipal discharges to
natural wetlands,  a minimum of secondary treat-
ment is required, and applicable water quality stand-
ards for the wetland and  adjacent waters must be
met. Natural wetlands are nearly always "waters of
the U.S." and are afforded the same level of protec-
tion as other surface waters with regard to stand-
ards and minimum treatment requirements. There
are no minimum  treatment requirements for wet-
lands created solely for the purpose of wastewater
treatment that do not qualify as "waters of the U.S."
The discharge from the created wetlands that do not
qualify as "waters of the U.S." must meet applicable
standards for the receiving water. EPA encourages
the expansion of wetland resources through the
creation of engineered wetlands while allowing the
use of natural wetlands for  wastewater treatment
only under limited conditions. Water quality stand-
ards for wetlands can prevent the misuse and  over-
use of natural wetlands for treatment through adop-
tion of proper  uses and criteria  and application of
State antidegradation policies.

  6.2.2  Stormwater Treatment
  Stormwater discharges to  wetlands can provide
an important component of the freshwater supply to
wetlands.   However, Stormwater discharges from
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various land use activities can also contain a sig-
nificant amount of pollutants.  Section 402(p)(2)  of
the Clean Water Act requires that EPA, or States
with authorized National Pollutant  Discharge
Elimination System  (NPDES) programs, issue
NPDES permits for certain types of stormwater dis-
charges.   EPA is in  the process of developing
regulations defining the scope jof this program as
well as developing  permits for these discharges.
Stormwater permits can be used to require controls
that reduce the pollutants discharged to wetlands as
well as other waters of the United States.  In addi-
tion, some of the stormwater management controls
anticipated in permits will require creation of wet-
lands or structures with some of the attributes  of
wetlands for the single purpose of water treatment.

  EPA anticipates that the policy for stormwater dis-
charges to wetlands will  have some similarities to
the policies for municipal wastewater discharges to
wetlands.  Natural wetlands are "waters  of the
United States" and are afforded a level of protection
with regard to water quality standards and technol-
ogy-based treatment requirements. The discharge
from created wetlands must meet applicable water
quality standards for the receiving waters.  EPA will
issue technical guidance  on permitting  stormwater
discharges, including  permitting  stormwater dis-
charges to wetlands, over the next few years.

  6.2.3  Fills
  Section 404 of the CWA regulates the discharge of
dredged and fill  material  into "waters of the U.S."
The Corps of Engineers' regulations for the 404 pro-
gram are contained in  33 CFR Parts 320-330, while
EPA's regulations for the 404 program are contained
in 40 CFR Part 230-33.

  One State uses the following guidelines for fills  in
their internal Section 401 review guidelines:

  (a)   if the project is not water dependent, cer-
       tification is denied;

  (b)   if the project is water dependent, certifica-
       tion is denied if there is a viable alternative
       (e.g., available upland nearby is a viable
       alternative);

  (c)   if no viable alternatives exist and impacts to
       wetland cannot be made acceptable
       through  conditions on certification (e.g.,
       fish movement criteria, creation of flood-
       ways to bypass oxbows,  flow through
       criteria), certification is denied.

   Some  modification of this may be incorporated
into States' water quality standards.  The States.are
encouraged  to provide  a  linkage  in their water
quality standards to the determination of "significant
degradation"  as required  under EPA guidelines (40
CFR 230.10(c)) and other applicable State laws af-
fecting the disposal of dredged or fill materials  in
wetlands; see Section 5.1.

   6.2.4  Nonpoint Source Assessment
   and Control
   Wetlands, as with other waters, are impacted by
nonpoint sources of  pollution.   Many wetlands,
through their assimilative  capacity for nutrients and
sediment, also can serve an important water quality
control function for nonpoint source pollution ef-
fects on  waters adjacent to, or downstream of, the
wetlands.  Water quality  standards  play a pivotal
role in both of the above. First, Section 319 of the
CWA requires the States  to complete assessments
of nonpoint source (NPS) impacts to State waters,
including wetlands, and  to prepare management
programs to  control NPS impacts.  Water quality
standards for wetlands can form the  basis for these
assessments  and management programs for  wet-
lands.  Second, water quality standards require-
ments for other surface waters such as rivers, lakes,
and estuaries can provide an impetus for States to
protect,  enhance, and restore wetlands to  help
achieve nonpoint source  control  and water quality
standards objectives for adjacent and downstream
waters. The Office of Water Regulations and Stand-
ards and the Office of Wetlands Protection  have
developed guidance on the coordination of wetland
and NPS control programs entitled National
Guidance - Wetlands and Nonpoint Source Control
Programs (USEPA 1990c).

6.3  Monitoring
  Water  quality management activities,  including
the permitting of wastewater  and stormwater dis-
charges,  the assessment and control of NPS pollu-
tion, and  waste disposal activities (sewage sludge,
CERCLA,  RCRA) require sufficient monitoring to en-
sure that the designated  and existing uses of
"waters of the U.S." are maintained and protected.
In addition,  Section 305(b) of the  CWA requires
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States to report on the overall status of their waters
in attaining water quality standards.  The inclusion
of wetlands in water quality standards provides the
basis for conducting both wetland-specific  and
status and trend monitoring of State wetland resour-
ces.  Information gathered from the 305(b) reports
may also be used  to update and refine the desig-
nated wetland uses. The monitoring of wetlands is
made difficult by  limitations in State resources.
Where regulated activities impact wetlands or other
surface waters, States should provide regulatory in-
centives and negotiate monitoring responsibilities of
the  party conducting the regulated activity.

  Monitoring of activities  impacting specific  wet-
lands may include several approaches. Monitoring
methods involving  biological  measurements, such
as plant,  macroinvertebrate, and fish (e.g., biomass
and diversity indices), have shown promise for
monitoring stream quality (Plafkin  et al.,  1989).
These types of indicators have not  been widely
tested for wetlands; see Section 7.1. However, the
State of Florida  has developed biological criteria as
part of their regulations governing the discharge  of
municipal wastewater to wetlands5.  The States are
encouraged to develop and test the use of biological
indicators. Other more traditional methods current-
ly applied to other surface waters, including but not
limited to the use of water quality criteria, sediment
quality criteria, and whole effluent toxicity, are  also
available for conducting monitoring of specific  wet-
lands.

  Discharges involving  persistent or bioaccumula-
tive contaminants may necessitate the monitoring of
the  fate of such contaminants through wetlands and
their impacts on aquatic life and wildlife.  The ex-
posure of birds and mammals to these contaminants
is accentuated by the frequent use of wetlands by
wildlife and the concentration of contaminants  in
wetlands through sedimentation and other  proces-
ses.  States should conduct monitoring of these
contaminants in wetlands,  and  may require such
monitoring as part of regulatory activities involving
these contaminants.
  Status and trend monitoring of the wetland
resources overall may require additional ap-
proaches; see Section 3.1.  Given current gaps in
scientific knowledge concerning  indicators of wet-
land quality, monitoring  of wetlands over the next
few years may focus on the spatial extent (i.e., quan-
tity) and physical structure (e.g.,  plant types, diver-
sity, and distribution)  of wetland resources.  The
tracking of wetland acreage and plant communities
using aerial  photography can  provide information
that can augment the data collected on specific ac-
tivities impacting wetlands, as discussed above.

  EPA has developed guidance on the reporting of
wetland  conditions for the Section 305(b) program
entitled Guidelines for the Preparation of the 1990
State Water  Quality Assessment 305(b) Report
(USEPA 1989b). When assessing individual specific
wetlands, assessment information should be
managed in an automated data system compatible
with the Section 305(b) Waterbody System. In addi-
tion, the NWI program  provides technical  proce-
dures and protocols for tracking the spatial extent of
wetlands for the United States and subregions of the
United  States.   These sources provide the
framework for reporting on the  status and trends of
State wetland resources.

6.4  Mixing Zones and  Variances
  The guidance  on mixing zones  in the  Water
Quality Standards  Handbook (USEPA 1983b) and
the Technical Support Document for Water Quality-
Based Toxics Control (TSD) (USEPA 1985b) apply
to all surface waters, including wetlands.  This in-
cludes the point of application of acute and chronic
criteria.  As with other surface waters, mixing zones
may be  granted only when water is present, and
may be developed specifically for different  water
types.  Just  as mixing zone procedures are often
different for different water types and flow regimes
(e.g., free flowing streams versus  lakes and es-
tuaries),  separate procedures also  may be
developed specifically for wetlands.  Such  proce-
dures should meet the  requirements contained  in
the TSD.
    Florida Department of Environmental Regulations; State Regulations Part I, "Domestic Wastewater
    Facilities," Subpart C, "Design/Performance Considerations," 17-6.055, "Wetlands Applications."
                                               26

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  As in other State waters, variances may be
granted to discharges to wetlands.  Variances must
meet one or more  of the six requirements for the
removal of a designated use (40 CFR Part I31.10(g))
and must fully protect any existing  uses of the wet-
land.
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               Future  Directions
        EPA's  Office of Water Regulations and
        Standards' planning document Water
        Quality Standards Framework (USEPA -
Draft 1989e), identifies the major objectives for the
program and the activities necessary to meet these
objectives. Activities related to the development of
water quality standards for wetlands are separated
into  two phases:   (1) Phase 1 activities to be
developed by  the States by the end  of FY 1993,
discussed above; and (2) Phase 2 activities that will
require additional  research and program develop-
ment, which are discussed below.

7.1  Numeric Biological  Criteria
for  Wetlands
  Development of narrative biological criteria is in-
cluded in the first phase of the development of water
quality standards for wetlands; see Section 5.1.2.
The second phase involves the implementation of
numeric  biological criteria.  This effort  requires the
detailed  evaluation of the  components of wetland
communities to determine the structure and function
of unimpaired wetlands.  These measures serve as
reference conditions for evaluating the integrity of
other wetlands.  Regulatory activities involving dis-
charges  to wetlands (e.g., CWA Sections 402 and
404) can provide monitoring data to augment data
collected by the  States for the development  of
numeric  biological criteria;  see  Section 7.4.  The
development of numeric biological  criteria for wet-
lands will require additional  research and field test-
ing oveMhe next several years.

  Biological criteria are based on local and regional
biotic characteristics.  This is in contrast to the  na-
tionally based chemical-specific aquatic life criteria
developed by EPA under controlled laboratory con-
ditions.  The States will have primary responsibility
for developing and implementing biological criteria
for their surface  waters, including wetlands,  to
reflect local and  regional differences in  resident
biological communities.  EPA will work closely with
the States and  the EPA Office of Research and
Development to develop and test numeric biological
criteria for wetlands. Updates on this work will be
provided through  the Office of Water  Regulations
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and  Standards,  Criteria and  Standards Division's
regular newsletter.

7.2  Wildlife Criteria
  Wetlands are  important habitats for wildlife
species.  It is therefore important to consider wildlife
in developing criteria that protect the functions and
values of wetlands.  Existing chemical-specific
aquatic life criteria are derived by testing selected
aquatic  organisms by exposing  them to  con-
taminants in water.  Although considered to be
protective of aquatic life, these criteria often do not
account  for the  bioaccumulation  of these  con-
taminants, which may cause  a major impact on
wildlife using wetland resources.  Except for criteria
f