[Code of Federal Regulations]
[Title 40, Volume 21]
[Revised as of July 1, 2007]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR132.6]
[Page 491-545]
TITLE 40--PROTECTION OF ENVIRONMENT
CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
PART 132_WATER QUALITY GUIDANCE FOR THE GREAT
LAKES SYSTEM--Table of Contents
Sec. 132.6 Application of part 132 requirements in Great Lakes States and Tribes.
(a) Effective September 5, 2000, the requirements of Paragraph C.1
of Procedure 2 in Appendix F of this Part and the requirements of
paragraph F.2 of Procedure 5 in Appendix F of this Part shall apply to
discharges within the Great Lakes System in the State of Indiana.
(b) Effective September 5, 2000, the requirements of Procedure 3 in
Appendix F of this Part shall apply for purposes of developing total
maximum daily loads in the Great Lakes System in the State of Illinois.
(c) Effective September 5, 2000, the requirements of Paragraphs C.1
and D of Procedure 6 in Appendix F of this Part shall apply to
discharges within the Great Lakes System in the States of Indiana,
Michigan and Ohio.
(d) Effective November 6, 2000, Sec. 132.4(d)(2) shall apply to
waters designated as ``Class D'' under section 701.9 of Title 6 of the
New York State Codes, Rules and Regulations within the Great Lakes
System in the State of New York. For purposes of this paragraph, chronic
water quality criteria and values for the protection of aquatic life
adopted or developed pursuant to Sec. 132.4(a) through (c) are the
criteria and values adopted or developed by New York State Department of
Environmental Conservation (see section 703.5 of Title 6 of the New York
State Codes, Rules and Regulations) and approved by EPA under section
303(c) of the Clean Water Act.
(e) Effective November 6, 2000, the criteria for mercury contained
in Table 4 of this part shall apply to waters within the Great Lakes
System in the State of New York.
(f) Effective December 6, 2000, the acute and chronic aquatic life
criteria for copper and nickel in Tables 1 and 2 of this part and the
chronic aquatic life criterion for endrin in Table 2 of this part shall
apply to the waters of the Great Lakes System in the State of Wisconsin.
(g) Effective February 5, 2001, the chronic aquatic life criterion
for selenium in Table 2 of this part shall apply to the waters of the
Great Lakes System in the State of Wisconsin.
(h) Effective December 6, 2000, the requirements of procedure 3 in
appendix F of this part shall apply for purposes of developing total
maximum daily loads in the Great Lakes System in the State of Wisconsin.
(i) Effective December 6, 2000, the requirements of paragraphs D and
E of procedure 5 in appendix F of this part shall apply to discharges
within the Great Lakes System in the State of Wisconsin.
(j) Effective December 6, 2000, the requirements of paragraph D of
procedure 6 in appendix F of this part shall apply to discharges within
the Great Lakes System in the State of Wisconsin.
[65 FR 47874, Aug. 4, 2000, as amended at 65 FR 59737, Oct. 6, 2000; 65
FR 66511, Nov. 6, 2000]
Tables to Part 132
Table 1--Acute Water Quality Criteria for Protection of Aquatic Life in
Ambient Water
EPA recommends that metals criteria be expressed as dissolved
concentrations (see appendix A, I.A.4 for more information regarding
metals criteria).
(a)
------------------------------------------------------------------------
CMC Conversion
Chemical ([micro]g/ factor
L) (CF)
------------------------------------------------------------------------
Arsenic (III)................................... \a,b\ 1.000
339.8
Chromium (VI)................................... \a,b\ 0.982
16.02
Cyanide......................................... \c\ 22 n/a
Dieldrin........................................ \d\ 0.24 n/a
Endrin.......................................... \d\ 0.086 n/a
Lindane......................................... \d\ 0.95 n/a
Mercury (II).................................... \a,b\ 0.85
1.694
Parathion....................................... \d\ 0.065 n/a
------------------------------------------------------------------------
\a\ CMC=CMC\tr\.
\b\ CMC\d\=(CMC\tr\) CF. The CMC\d\ shall be rounded to two significant
digits.
\c\ CMC should be considered free cyanide as CN.
\d\ CMC=CMC\t\.
Notes:
The term ``n/a'' means not applicable.
CMC is Criterion Maximum Concentration.
CMC\tr\ is the CMC expressed as total recoverable.
CMC\d\ is the CMC expressed as a dissolved concentration.
CMC\t\ is the CMC expressed as a total concentration.
[[Page 492]]
(b)
------------------------------------------------------------------------
Conversion
Chemical mA bA factor
(CF)
------------------------------------------------------------------------
Cadmium \a,b\......................... 1.128 -3.6867 0.85
Chromium (III) \a,b\.................. 0.819 +3.7256 0.316
Copper \a,b\.......................... 0.9422 -1.700 0.960
Nickel \a,b\.......................... 0.846 +2.255 0.998
Pentachlorophenol \c\................. 1.005 -4.869 n/a
Zinc \a,b\............................ 0.8473 +0.884 0.978
------------------------------------------------------------------------
\a\ CMC\tr\=exp {mA [ln (hardness)]+bA{time} .
\b\ CMC\d\=(CMC\tr\) CF. The CMC\d\ shall be rounded to two significant
digits.
\c\ CMC\t\=exp mA [pH]+bA{time} . The CMC\t\ shall be rounded
to two significant digits.
Notes:
The term ``exp'' represents the base e exponential function.
The term ``n/a'' means not applicable.
CMC is Criterion Maximum Concentration.
CMC\tr\ is the CMC expressed as total recoverable.
CMC\d\ is the CMC expressed as a dissolved concentration.
CMC\t\ is the CMC expressed as a total concentration.
[60 FR 15387, Mar. 23, 1995, as amended at 65 FR 35286, June 2, 2000]
Table 2--Chronic Water Quality Criteria for Protection of Aquatic Life
in Ambient Water
EPA recommends that metals criteria be expressed as dissolved
concentrations (see appendix A, I.A.4 for more information regarding
metals criteria).
(a)
------------------------------------------------------------------------
CCC Conversion
Chemical ([micro]g/ factor
L) (CF)
------------------------------------------------------------------------
Arsenic (III).................................. \a,b\ 147.9 1.000
Chromium (VI).................................. \a,b\ 10.98 0.962
Cyanide........................................ \c\ 5.2 n/a
Dieldrin....................................... \d\ 0.056 n/a
Endrin......................................... \d\ 0.036 n/a
Mercury (II)................................... \a,b\ 0.85
0.9081
Parathion...................................... \d\ 0.013 n/a
Selenium....................................... \a,b\ 5 0.922
------------------------------------------------------------------------
\a\ CCC=CCC\tr\.
\b\ CCC\d\=(CCC\tr\) CF. The CCC\d\ shall be rounded to two significant
digits.
\c\ CCC should be considered free cyanide as CN.
\d\ CCC=CCC\t\.
Notes:
The term ``n/a'' means not applicable.
CCC is Criterion Continuous Concentration.
CCC\tr\ is the CCC expressed as total recoverable.
CCC\d\ is the CCC expressed as a dissolved concentration.
CCC\t\ is the CCC expressed as a total concentration.
(b)
------------------------------------------------------------------------
Conversion
Chemical mc bc factor
(CF)
------------------------------------------------------------------------
Cadmium \a,b\............................. 0.7852 -2.715 0.850
Chromium (III) \a,b\...................... 0.819 +0.6848 0.860
Copper \a,b\.............................. 0.8545 -1.702 0.960
Nickel \a,b\.............................. 0.846 +0.0584 0.997
Pentachlorophenol \c\..................... 1.005 -5.134 n/a
Zinc \a,b\................................ 0.8473 +0.884 0.986
------------------------------------------------------------------------
\a\ CCC\tr\=exp {mc[ln (hardness)]+bc{time} .
\b\ CCCd=(CCC\tr\) (CF). The CCC\d\ shall be rounded to two significant
digits.
\c\ CMC\t\=exp {mA[pH]+bA{time} . The CMC\t\ shall be rounded to two
significant digits.
Notes:
The term ``exp'' represents the base e exponential function.
The term ``n/a'' means not applicable.
CCC is Criterion Continuous Concentration.
CCC\tr\ is the CCC expressed as total recoverable.
CCC\d\ is the CCC expressed as a dissolved concentration.
CCC\t\ is the CCC expressed as a total concentration.
Table 3--Water Quality Criteria for Protection of Human Health
----------------------------------------------------------------------------------------------------------------
HNV ([micro]g/L) HCV ([micro]g/L)
Chemical ---------------------------------------------
Drinking Nondrinking Drinking Nondrinking
----------------------------------------------------------------------------------------------------------------
Benzene........................................................... 1.9E1 5.1E2 1.2E1 3.1E2
Chlordane......................................................... 1.4E-3 1.4E-3 2.5E-4 2.5E-4
Chlorobenzene..................................................... 4.7E2 3.2E3
Cyanides.......................................................... 6.0E2 4.8E4
DDT............................................................... 2.0E-3 2.0E-3 1.5E-4 1.5E-4
Dieldrin.......................................................... 4.1E-4 4.1E-4 6.5E-6 6.5E-6
2,4-Dimethylphenol................................................ 4.5E2 8.7E3
2,4-Dinitrophenol................................................. 5.5E1 2.8E3
Hexachlorobenzene................................................. 4.6E-2 4.6E-2 4.5E-4 4.5E-4
Hexachloroethane.................................................. 6.0 7.6 5.3 6.7
Lindane........................................................... 4.7E-1 5.0E-1
Mercury \1\....................................................... 1.8E-3 1.8E-3
Methylene chloride................................................ 1.6E3 9.0E4 4.7E1 2.6E3
2,3,7,8-TCDD...................................................... 6.7E-8 6.7E-8 8.6E-9 8.6E-9
Toluene........................................................... 5.6E3 5.1E4
Toxaphene......................................................... 6.8E-5 6.8E-5
Trichloroethylene................................................. 2.9E1 3.7E2
----------------------------------------------------------------------------------------------------------------
\1\ Includes methylmercury.
[60 FR 15387, Mar. 23, 1995, as amended at 62 FR 11731, Mar. 12, 1997;
62 FR 52924, Oct. 9, 1997]
Table 4--Water Quality Criteria for Protection of Wildlife
------------------------------------------------------------------------
Chemical Criteria ([micro]g/L)
------------------------------------------------------------------------
DDT and metabolites........................ 1.1E-5
Mercury (including methylmercury).......... 1.3E-3
PCBs (class)............................... 1.2E-4
2,3,7,8-TCDD............................... 3.1E-9
------------------------------------------------------------------------
[60 FR 15387, Mar. 23, 1995, as amended at 62 FR 11731, Mar. 12, 1997]
Table 5--Pollutants Subject to Federal, State, and Tribal Requirements
Alkalinity
Ammonia
Bacteria
Biochemical oxygen demand (BOD)
Chlorine
Color
Dissolved oxygen
Dissolved solids
pH
Phosphorus
Salinity
Temperature
Total and suspended solids
[[Page 493]]
Turbidity
Table 6--Pollutants of Initial Focus in the Great Lakes Water Quality
Initiative
A. Pollutants that are bioaccumulative chemicals of concern (BCCs):
Chlordane
4,4'-DDD; p,p'-DDD; 4,4'-TDE; p,p'-TDE
4,4'-DDE; p,p'-DDE
4,4'-DDT; p,p'-DDT
Dieldrin
Hexachlorobenzene
Hexachlorobutadiene; hexachloro-1, 3-butadiene
Hexachlorocyclohexanes; BHCs
alpha-Hexachlorocyclohexane; alpha-BHC
beta-Hexachlorocyclohexane; beta-BHC
delta-Hexachlorocyclohexane; delta-BHC
Lindane; gamma-hexachlorocyclohexane; gamma-BHC
Mercury
Mirex
Octachlorostyrene
PCBs; polychlorinated biphenyls
Pentachlorobenzene
Photomirex
2,3,7,8-TCDD; dioxin
1,2,3,4-Tetrachlorobenzene
1,2,4,5-Tetrachlorobenzene Toxaphene
B. Pollutants that are not bioaccumulative chemicals of concern:
Acenaphthene
Acenaphthylene
Acrolein; 2-propenal
Acrylonitrile
Aldrin
Aluminum
Anthracene
Antimony
Arsenic
Asbestos
1,2-Benzanthracene; benz[a]anthracene
Benzene
Benzidine
Benzo[a]pyrene; 3,4-benzopyrene
3,4-Benzofluoranthene; benzo[b]fluoranthene
11,12-Benzofluoranthene; benzo[k]fluoranthene
1,12-Benzoperylene; benzo[ghi]perylene
Beryllium
Bis(2-chloroethoxy) methane
Bis(2-chloroethyl) ether
Bis(2-chloroisopropyl) ether
Bromoform; tribomomethane
4-Bromophenyl phenyl ether
Butyl benzyl phthalate
Cadmium
Carbon tetrachloride; tetrachloromethane
Chlorobenzene
p-Chloro-m-cresol; 4-chloro-3-methylphenol
Chlorodibromomethane
Chlorethane
2-Chloroethyl vinyl ether
Chloroform; trichloromethane
2-Chloronaphthalene
2-Chlorophenol
4-Chlorophenyl phenyl ether
Chlorpyrifos
Chromium
Chrysene
Copper
Cyanide
2,4-D; 2,4-Dichlorophenoxyacetic acid
DEHP; di(2-ethylhexyl) phthalate
Diazinon
1,2:5,6-Dibenzanthracene; dibenz[a,h]anthracene
Dibutyl phthalate; di-n-butyl phthalate
1,2-Dichlorobenzene
1,3-Dichlorobenzene
1,4-Dichlorobenzene
3,3'-Dichlorobenzidine
Dichlorobromomethane; bromodichloromethane
1,1-Dichloroethane
1,2-Dichloroethane
1,1-Dichloroethylene; vinylidene chloride
1,2-trans-Dichloroethylene
2,4-Dichlorophenol
1,2-Dichloropropane
1,3-Dichloropropene; 1,3-dichloropropylene
Diethyl phthalate
2,4-Dimethylphenol; 2,4-xylenol
Dimethyl phthalate
4,6-Dinitro-o-cresol; 2-methyl-4,6-dinitrophenol
2,4-Dinitrophenol
2,4-Dinitrotoluene
2,6-Dinitrotoluene
Dioctyl phthalate; di-n-octyl phthalate
1,2-Diphenylhydrazine
Endosulfan; thiodan
alpha-Endosulfan
beta-Endosulfan
Endosulfan sulfate
Endrin
Endrin aldehyde
Ethylbenzene
Fluoranthene
Fluorene; 9H-fluorene
Fluoride
Guthion
Heptachlor
Heptachlor epoxide
Hexachlorocyclopentadiene
Hexachloroethane
Indeno[1,2,3-cd]pyrene; 2,3-o-phenylene pyrene
Isophorone
Lead
Malathion
Methoxychlor
Methyl bromide; bromomethane
Methyl chloride; chloromethane
Methylene chloride; dichloromethane
Napthalene
Nickel
Nitrobenzene
2-Nitrophenol
4-Nitrophenol
N-Nitrosodimethylamine
N-Nitrosodiphenylamine
[[Page 494]]
N-Nitrosodipropylamine; N-nitrosodi-n-propylamine
Parathion
Pentachlorophenol
Phenanthrene
Phenol
Iron
Pyrene
Selenium
Silver
1,1,2,2-Tetrachloroethane
Tetrachloroethylene
Thallium
Toluene; methylbenzene
1,2,4-Trichlorobenzene
1,1,1-Trichloroethane
1,1,2-Trichloroethane
Trichloroethylene; trichloroethene
2,4,6-Trichlorophenol
Vinyl chloride; chloroethylene; chloroethene
Zinc
Appendix A to Part 132--Great Lakes Water Quality Initiative
Methodologies for Development of Aquatic Life Criteria and Values
Methodology for Deriving Aquatic Life Criteria: Tier I
Great Lakes States and Tribes shall adopt provisions consistent with
(as protective as) this appendix.
I. Definitions
A. Material of Concern. When defining the material of concern the
following should be considered:
1. Each separate chemical that does not ionize substantially in most
natural bodies of water should usually be considered a separate
material, except possibly for structurally similar organic compounds
that only exist in large quantities as commercial mixtures of the
various compounds and apparently have similar biological, chemical,
physical, and toxicological properties.
2. For chemicals that ionize substantially in most natural bodies of
water (e.g., some phenols and organic acids, some salts of phenols and
organic acids, and most inorganic salts and coordination complexes of
metals and metalloid), all forms that would be in chemical equilibrium
should usually be considered one material. Each different oxidation
state of a metal and each different non-ionizable covalently bonded
organometallic compound should usually be considered a separate
material.
3. The definition of the material of concern should include an
operational analytical component. Identification of a material simply as
``sodium,'' for example, implies ``total sodium,'' but leaves room for
doubt. If ``total'' is meant, it must be explicitly stated. Even
``total'' has different operational definitions, some of which do not
necessarily measure ``all that is there'' in all samples. Thus, it is
also necessary to reference or describe the analytical method that is
intended. The selection of the operational analytical component should
take into account the analytical and environmental chemistry of the
material and various practical considerations, such as labor and
equipment requirements, and whether the method would require measurement
in the field or would allow measurement after samples are transported to
a laboratory.
a. The primary requirements of the operational analytical component
are that it be appropriate for use on samples of receiving water, that
it be compatible with the available toxicity and bioaccumulation data
without making extrapolations that are too hypothetical, and that it
rarely result in underprotection or overprotection of aquatic organisms
and their uses. Toxicity is the property of a material, or combination
of materials, to adversely affect organisms.
b. Because an ideal analytical measurement will rarely be available,
an appropriate compromise measurement will usually have to be used. This
compromise measurement must fit with the general approach that if an
ambient concentration is lower than the criterion, unacceptable effects
will probably not occur, i.e., the compromise measure must not err on
the side of underprotection when measurements are made on a surface
water. What is an appropriate measurement in one situation might not be
appropriate for another. For example, because the chemical and physical
properties of an effluent are usually quite different from those of the
receiving water, an analytical method that is appropriate for analyzing
an effluent might not be appropriate for expressing a criterion, and
vice versa. A criterion should be based on an appropriate analytical
measurement, but the criterion is not rendered useless if an ideal
measurement either is not available or is not feasible.
Note: The analytical chemistry of the material might have to be
taken into account when defining the material or when judging the
acceptability of some toxicity tests, but a criterion must not be based
on the sensitivity of an analytical method. When aquatic organisms are
more sensitive than routine analytical methods, the proper solution is
to develop better analytical methods.
4. It is now the policy of EPA that the use of dissolved metal to
set and measure compliance with water quality standards is the
recommended approach, because dissolved metal more closely approximates
the bioavailable fraction of metal in the water column that does total
recoverable metal. One reason is that a primary mechanism for water
column toxicity is adsorption at the gill surface which requires metals
to be in
[[Page 495]]
the dissolved form. Reasons for the consideration of total recoverable
metals criteria include risk management considerations not covered by
evaluation of water column toxicity. A risk manager may consider
sediments and food chain effects and may decide to take a conservative
approach for metals, considering that metals are very persistent
chemicals. This approach could include the use of total recoverable
metal in water quality standards. A range of different risk management
decisions can be justified. EPA recommends that State water quality
standards be based on dissolved metal. EPA will also approve a State
risk management decision to adopt standards based on total recoverable
metal, if those standards are otherwise approvable under this program.
B. Acute Toxicity. Concurrent and delayed adverse effect(s) that
results from an acute exposure and occurs within any short observation
period which begins when the exposure begins, may extend beyond the
exposure period, and usually does not constitute a substantial portion
of the life span of the organism. (Concurrent toxicity is an adverse
effect to an organism that results from, and occurs during, its exposure
to one or more test materials.) Exposure constitutes contact with a
chemical or physical agent. Acute exposure, however, is exposure of an
organism for any short period which usually does not constitute a
substantial portion of its life span.
C. Chronic Toxicity. Concurrent and delayed adverse effect(s) that
occurs only as a result of a chronic exposure. Chronic exposure is
exposure of an organism for any long period or for a substantial portion
of its life span.
II. Collection of Data
A. Collect all data available on the material concerning toxicity to
aquatic animals and plants.
B. All data that are used should be available in typed, dated, and
signed hard copy (e.g., publication, manuscript, letter, memorandum,
etc.) with enough supporting information to indicate that acceptable
test procedures were used and that the results are reliable. In some
cases, it might be appropriate to obtain written information from the
investigator, if possible. Information that is not available for
distribution shall not be used.
C. Questionable data, whether published or unpublished, must not be
used. For example, data must be rejected if they are from tests that did
not contain a control treatment, tests in which too many organisms in
the control treatment died or showed signs of stress or disease, and
tests in which distilled or deionized water was used as the dilution
water without the addition of appropriate salts.
D. Data on technical grade materials may be used if appropriate, but
data on formulated mixtures and emulsifiable concentrates of the
material must not be used.
E. For some highly volatile, hydrolyzable, or degradable materials,
it might be appropriate to use only results of flow-through tests in
which the concentrations of test material in test solutions were
measured using acceptable analytical methods. A flow-through test is a
test with aquatic organisms in which test solutions flow into constant-
volume test chambers either intermittently (e.g., every few minutes) or
continuously, with the excess flowing out.
F. Data must be rejected if obtained using:
1. Brine shrimp, because they usually only occur naturally in water
with salinity greater than 35 g/kg.
2. Species that do not have reproducing wild populations in North
America.
3. Organisms that were previously exposed to substantial
concentrations of the test material or other contaminants.
4. Saltwater species except for use in deriving acute-chronic
ratios. An ACR is a standard measure of the acute toxicity of a material
divided by an appropriate measure of the chronic toxicity of the same
material under comparable conditions.
G. Questionable data, data on formulated mixtures and emulsifiable
concentrates, and data obtained with species non-resident to North
America or previously exposed organisms may be used to provide auxiliary
information but must not be used in the derivation of criteria.
III. Required Data
A. Certain data should be available to help ensure that each of the
major kinds of possible adverse effects receives adequate consideration.
An adverse effect is a change in an organism that is harmful to the
organism. Exposure means contact with a chemical or physical agent.
Results of acute and chronic toxicity tests with representative species
of aquatic animals are necessary so that data available for tested
species can be considered a useful indication of the sensitivities of
appropriate untested species. Fewer data concerning toxicity to aquatic
plants are usually available because procedures for conducting tests
with plants and interpreting the results of such tests are not as well
developed.
B. To derive a Great Lakes Tier I criterion for aquatic organisms
and their uses, the following must be available:
1. Results of acceptable acute (or chronic) tests (see section IV or
VI of this appendix) with at least one species of freshwater animal in
at least eight different families such that all of the following are
included:
a. The family Salmonidae in the class Osteichthyes;
b. One other family (preferably a commercially or recreationally
important,
[[Page 496]]
warmwater species) in the class Osteichthyes (e.g., bluegill, channel
catfish);
c. A third family in the phylum Chordata (e.g., fish, amphibian);
d. A planktonic crustacean (e.g., a cladoceran, copepod);
e. A benthic crustacean (e.g., ostracod, isopod, amphipod,
crayfish);
f. An insect (e.g., mayfly, dragonfly, damselfly, stonefly,
caddisfly, mosquito, midge);
g. A family in a phylum other than Arthropoda or Chordata (e.g.,
Rotifera, Annelida, Mollusca);
h. A family in any order of insect or any phylum not already
represented.
2. Acute-chronic ratios (see section VI of this appendix) with at
least one species of aquatic animal in at least three different families
provided that of the three species:
a. At least one is a fish;
b. At least one is an invertebrate; and
c. At least one species is an acutely sensitive freshwater species
(the other two may be saltwater species).
3. Results of at least one acceptable test with a freshwater algae
or vascular plant is desirable but not required for criterion derivation
(see section VIII of this appendix). If plants are among the aquatic
organisms most sensitive to the material, results of a test with a plant
in another phylum (division) should also be available.
C. If all required data are available, a numerical criterion can
usually be derived except in special cases. For example, derivation of a
chronic criterion might not be possible if the available ACRs vary by
more than a factor of ten with no apparent pattern. Also, if a criterion
is to be related to a water quality characteristic (see sections V and
VII of this appendix), more data will be required.
D. Confidence in a criterion usually increases as the amount of
available pertinent information increases. Thus, additional data are
usually desirable.
IV. Final Acute Value
A. Appropriate measures of the acute (short-term) toxicity of the
material to a variety of species of aquatic animals are used to
calculate the Final Acute Value (FAV). The calculated Final Acute Value
is a calculated estimate of the concentration of a test material such
that 95 percent of the genera (with which acceptable acute toxicity
tests have been conducted on the material) have higher Genus Mean Acute
Values (GMAVs). An acute test is a comparative study in which organisms,
that are subjected to different treatments, are observed for a short
period usually not constituting a substantial portion of their life
span. However, in some cases, the Species Mean Acute Value (SMAV) of a
commercially or recreationally important species of the Great Lakes
System is lower than the calculated FAV, then the SMAV replaces the
calculated FAV in order to provide protection for that important
species.
B. Acute toxicity tests shall be conducted using acceptable
procedures. For good examples of acceptable procedures see American
Society for Testing and Materials (ASTM) Standard E 729, Guide for
Conducting Acute Toxicity Tests with Fishes, Macroinvertebrates, and
Amphibians.
C. Except for results with saltwater annelids and mysids, results of
acute tests during which the test organisms were fed should not be used,
unless data indicate that the food did not affect the toxicity of the
test material. (Note: If the minimum acute-chronic ratio data
requirements (as described in section III.B.2 of this appendix) are not
met with freshwater data alone, saltwater data may be used.)
D. Results of acute tests conducted in unusual dilution water, e.g.,
dilution water in which total organic carbon or particulate matter
exceeded five mg/L, should not be used, unless a relationship is
developed between acute toxicity and organic carbon or particulate
matter, or unless data show that organic carbon or particulate matter,
etc., do not affect toxicity.
E. Acute values must be based upon endpoints which reflect the total
severe adverse impact of the test material on the organisms used in the
test. Therefore, only the following kinds of data on acute toxicity to
aquatic animals shall be used:
1. Tests with daphnids and other cladocerans must be started with
organisms less than 24 hours old and tests with midges must be started
with second or third instar larvae. It is preferred that the results
should be the 48-hour EC50 based on the total percentage of organisms
killed and immobilized. If such an EC50 is not available for a test, the
48-hour LC50 should be used in place of the desired 48-hour EC50. An
EC50 or LC50 of longer than 48 hours can be used as long as the animals
were not fed and the control animals were acceptable at the end of the
test. An EC50 is a statistically or graphically estimated concentration
that is expected to cause one or more specified effects in 50% of a
group of organisms under specified conditions. An LC50 is a
statistically or graphically estimated concentration that is expected to
be lethal to 50% of a group of organisms under specified conditions.
2. It is preferred that the results of a test with embryos and
larvae of barnacles, bivalve molluscs (clams, mussels, oysters and
scallops), sea urchins, lobsters, crabs, shrimp and abalones be the 96-
hour EC50 based on the percentage of organisms with incompletely
developed shells plus the percentage of organisms killed. If such an
EC50 is not available from a test, of the values that are
[[Page 497]]
available from the test, the lowest of the following should be used in
place of the desired 96-hour EC50: 48- to 96-hour EC50s based on
percentage of organisms with incompletely developed shells plus
percentage of organisms killed, 48- to 96-hour EC50s based upon
percentage of organisms with incompletely developed shells, and 48-hour
to 96-hour LC50s. (Note: If the minimum acute-chronic ratio data
requirements (as described in section III.B.2 of this appendix) are not
met with freshwater data alone, saltwater data may be used.)
3. It is preferred that the result of tests with all other aquatic
animal species and older life stages of barnacles, bivalve molluscs
(clams, mussels, oysters and scallops), sea urchins, lobsters, crabs,
shrimp and abalones be the 96-hour EC50 based on percentage of organisms
exhibiting loss of equilibrium plus percentage of organisms immobilized
plus percentage of organisms killed. If such an EC50 is not available
from a test, of the values that are available from a test the lower of
the following should be used in place of the desired 96-hour EC50: the
96-hour EC50 based on percentage of organisms exhibiting loss of
equilibrium plus percentage of organisms immobilized and the 96-hour
LC50.
4. Tests whose results take into account the number of young
produced, such as most tests with protozoans, are not considered acute
tests, even if the duration was 96 hours or less.
5. If the tests were conducted properly, acute values reported as
``greater than'' values and those which are above the solubility of the
test material should be used, because rejection of such acute values
would bias the Final Acute Value by eliminating acute values for
resistant species.
F. If the acute toxicity of the material to aquatic animals has been
shown to be related to a water quality characteristic such as hardness
or particulate matter for freshwater animals, refer to section V of this
appendix.
G. The agreement of the data within and between species must be
considered. Acute values that appear to be questionable in comparison
with other acute and chronic data for the same species and for other
species in the same genus must not be used. For example, if the acute
values available for a species or genus differ by more than a factor of
10, rejection of some or all of the values would be appropriate, absent
countervailing circumstances.
H. If the available data indicate that one or more life stages are
at least a factor of two more resistant than one or more other life
stages of the same species, the data for the more resistant life stages
must not be used in the calculation of the SMAV because a species cannot
be considered protected from acute toxicity if all of the life stages
are not protected.
I. For each species for which at least one acute value is available,
the SMAV shall be calculated as the geometric mean of the results of all
acceptable flow-through acute toxicity tests in which the concentrations
of test material were measured with the most sensitive tested life stage
of the species. For a species for which no such result is available, the
SMAV shall be calculated as the geometric mean of all acceptable acute
toxicity tests with the most sensitive tested life stage, i.e., results
of flow-through tests in which the concentrations were not measured and
results of static and renewal tests based on initial concentrations
(nominal concentrations are acceptable for most test materials if
measured concentrations are not available) of test material. A renewal
test is a test with aquatic organisms in which either the test solution
in a test chamber is removed and replaced at least once during the test
or the test organisms are transferred into a new test solution of the
same composition at least once during the test. A static test is a test
with aquatic organisms in which the solution and organisms that are in a
test chamber at the beginning of the test remain in the chamber until
the end of the test, except for removal of dead test organisms.
Note 1: Data reported by original investigators must not be rounded
off. Results of all intermediate calculations must not be rounded off to
fewer than four significant digits.
Note 2: The geometric mean of N numbers is the Nth root of the
product of the N numbers. Alternatively, the geometric mean can be
calculated by adding the logarithms of the N numbers, dividing the sum
by N, and taking the antilog of the quotient. The geometric mean of two
numbers is the square root of the product of the two numbers, and the
geometric mean of one number is that number. Either natural (base e) or
common (base 10) logarithms can be used to calculate geometric means as
long as they are used consistently within each set of data, i.e., the
antilog used must match the logarithms used.
Note 3: Geometric means, rather than arithmetic means, are used here
because the distributions of sensitivities of individual organisms in
toxicity tests on most materials and the distributions of sensitivities
of species within a genus are more likely to be lognormal than normal.
Similarly, geometric means are used for ACRs because quotients are
likely to be closer to lognormal than normal distributions. In addition,
division of the geometric mean of a set of numerators by the geometric
mean of the set of denominators will result in the
[[Page 498]]
geometric mean of the set of corresponding quotients.
J. For each genus for which one or more SMAVs are available, the
GMAV shall be calculated as the geometric mean of the SMAVs available
for the genus.
K. Order the GMAVs from high to low.
L. Assign ranks, R, to the GMAVs from ``1'' for the lowest to ``N''
for the highest. If two or more GMAVs are identical, assign them
successive ranks.
M. Calculate the cumulative probability, P, for each GMAV as R/
(N+1).
N. Select the four GMAVs which have cumulative probabilities closest
to 0.05 (if there are fewer than 59 GMAVs, these will always be the four
lowest GMAVs).
O. Using the four selected GMAVs, and Ps, calculate
[GRAPHIC] [TIFF OMITTED] TR23MR95.104
Note: Natural logarithms (logarithms to base e, denoted as ln) are
used herein merely because they are easier to use on some hand
calculators and computers than common (base 10) logarithms. Consistent
use of either will produce the same result.
P. If for a commercially or recreationally important species of the
Great Lakes System the geometric mean of the acute values from flow-
through tests in which the concentrations of test material were measured
is lower than the calculated Final Acute Value (FAV), then that
geometric mean must be used as the FAV instead of the calculated FAV.
Q. See section VI of this appendix.
V. Final Acute Equation
A. When enough data are available to show that acute toxicity to two
or more species is similarly related to a water quality characteristic,
the relationship shall be taken into account as described in sections
V.B through V.G of this appendix or using analysis of covariance. The
two methods are equivalent and produce identical results. The manual
method described below provides an understanding of this application of
covariance analysis, but computerized versions of covariance analysis
are much more convenient for analyzing large data sets. If two or more
factors affect toxicity, multiple regression analysis shall be used.
B. For each species for which comparable acute toxicity values are
available at two or more different values of the water quality
characteristic, perform a least squares regression of the acute toxicity
values on the corresponding values of the water quality characteristic
to obtain the slope and its 95 percent confidence limits for each
species.
Note: Because the best documented relationship is that between
hardness and acute toxicity of metals in fresh water and a log-log
relationship fits these data, geometric means and natural logarithms of
both toxicity and water quality are used in the rest of this section.
For relationships based on other water quality characteristics, such as
Ph, temperature, no transformation or a different transformation might
fit the data better, and appropriate changes will be necessary
throughout this section.
C. Decide whether the data for each species are relevant, taking
into account the range and number of the tested values of the water
quality characteristic and the degree of agreement within and between
species. For example, a slope based on six data points might be of
limited value if it is based only
[[Page 499]]
on data for a very narrow range of values of the water quality
characteristic. A slope based on only two data points, however, might be
useful if it is consistent with other information and if the two points
cover a broad enough range of the water quality characteristic. In
addition, acute values that appear to be questionable in comparison with
other acute and chronic data available for the same species and for
other species in the same genus should not be used. For example, if
after adjustment for the water quality characteristic, the acute values
available for a species or genus differ by more than a factor of 10,
rejection of some or all of the values would be appropriate, absent
countervailing justification. If useful slopes are not available for at
least one fish and one invertebrate or if the available slopes are too
dissimilar or if too few data are available to adequately define the
relationship between acute toxicity and the water quality
characteristic, return to section IV.G of this appendix, using the
results of tests conducted under conditions and in waters similar to
those commonly used for toxicity tests with the species.
D. For each species, calculate the geometric mean of the available
acute values and then divide each of the acute values for the species by
the geometric mean for the species. This normalizes the acute values so
that the geometric mean of the normalized values for each species
individually and for any combination of species is 1.0.
E. Similarly normalize the values of the water quality
characteristic for each species individually using the same procedure as
above.
F. Individually for each species perform a least squares regression
of the normalized acute values of the water quality characteristic. The
resulting slopes and 95 percent confidence limits will be identical to
those obtained in section V.B. of this appendix. If, however, the data
are actually plotted, the line of best fit for each individual species
will go through the point 1,1 in the center of the graph.
G. Treat all of the normalized data as if they were all for the same
species and perform a least squares regression of all of the normalized
acute values on the corresponding normalized values of the water quality
characteristic to obtain the pooled acute slope, V, and its 95 percent
confidence limits. If all of the normalized data are actually plotted,
the line of best fit will go through the point 1,1 in the center of the
graph.
H. For each species calculate the geometric mean, W, of the acute
toxicity values and the geometric mean, X, of the values of the water
quality characteristic. (These were calculated in sections V.D and V.E
of this appendix).
I. For each species, calculate the logarithm, Y, of the SMAV at a
selected value, Z, of the water quality characteristic using the
equation:
Y=ln W-V(ln X-ln Z)
J. For each species calculate the SMAV at X using the equation:
SMAV=e\Y\
Note: Alternatively, the SMAVs at Z can be obtained by skipping step
H above, using the equations in steps I and J to adjust each acute value
individually to Z, and then calculating the geometric mean of the
adjusted values for each species individually. This alternative
procedure allows an examination of the range of the adjusted acute
values for each species.
K. Obtain the FAV at Z by using the procedure described in sections
IV.J through IV.O of this appendix.
L. If, for a commercially or recreationally important species of the
Great Lakes System the geometric mean of the acute values at Z from
flow-through tests in which the concentrations of the test material were
measured is lower than the FAV at Z, then the geometric mean must be
used as the FAV instead of the FAV.
M. The Final Acute Equation is written as:
FAV=e\(V[ln(waterqualitycharacteristic)]=A-V[lnZ])\,
where:
V=pooled acute slope, and A=ln(FAV at Z).
Because V, A, and Z are known, the FAV can be calculated for any
selected value of the water quality characteristic.
VI. Final Chronic Value
A. Depending on the data that are available concerning chronic
toxicity to aquatic animals, the Final Chronic Value (FCV) can be
calculated in the same manner as the FAV or by dividing the FAV by the
Final Acute-Chronic Ratio (FACR). In some cases, it might not be
possible to calculate a FCV. The FCV is (a) a calculated estimate of the
concentration of a test material such that 95 percent of the genera
(with which acceptable chronic toxicity tests have been conducted on the
material) have higher GMCVs, or (b) the quotient of an FAV divided by an
appropriate ACR, or (c) the SMCV of an important and/or critical
species, if the SMCV is lower than the calculated estimate or the
quotient, whichever is applicable.
[[Page 500]]
Note: As the name implies, the ACR is a way of relating acute and
chronic toxicities.
B. Chronic values shall be based on results of flow-through (except
renewal is acceptable for daphnids) chronic tests in which the
concentrations of test material in the test solutions were properly
measured at appropriate times during the test. A chronic test is a
comparative study in which organisms, that are subjected to different
treatments, are observed for a long period or a substantial portion of
their life span.
C. Results of chronic tests in which survival, growth, or
reproduction in the control treatment was unacceptably low shall not be
used. The limits of acceptability will depend on the species.
D. Results of chronic tests conducted in unusual dilution water,
e.g., dilution water in which total organic carbon or particulate matter
exceeded five mg/L, should not be used, unless a relationship is
developed between chronic toxicity and organic carbon or particulate
matter, or unless data show that organic carbon, particulate matter,
etc., do not affect toxicity.
E. Chronic values must be based on endpoints and lengths of exposure
appropriate to the species. Therefore, only results of the following
kinds of chronic toxicity tests shall be used:
1. Life-cycle toxicity tests consisting of exposures of each of two
or more groups of individuals of a species to a different concentration
of the test material throughout a life cycle. To ensure that all life
stages and life processes are exposed, tests with fish should begin with
embryos or newly hatched young less than 48 hours old, continue through
maturation and reproduction, and should end not less than 24 days (90
days for salmonids) after the hatching of the next generation. Tests
with daphnids should begin with young less than 24 hours old and last
for not less than 21 days, and for ceriodaphnids not less than seven
days. For good examples of acceptable procedures see American Society
for Testing and Materials (ASTM) Standard E 1193 Guide for conducting
renewal life-cycle toxicity tests with Daphnia magna and ASTM Standard E
1295 Guide for conducting three-brood, renewal toxicity tests with
Ceriodaphnia dubia. Tests with mysids should begin with young less than
24 hours old and continue until seven days past the median time of first
brood release in the controls. For fish, data should be obtained and
analyzed on survival and growth of adults and young, maturation of males
and females, eggs spawned per female, embryo viability (salmonids only),
and hatchability. For daphnids, data should be obtained and analyzed on
survival and young per female. For mysids, data should be obtained and
analyzed on survival, growth, and young per female.
2. Partial life-cycle toxicity tests consist of exposures of each of
two more groups of individuals of a species of fish to a different
concentration of the test material through most portions of a life
cycle. Partial life-cycle tests are allowed with fish species that
require more than a year to reach sexual maturity, so that all major
life stages can be exposed to the test material in less than 15 months.
A life-cycle test is a comparative study in which organisms, that are
subjected to different treatments, are observed at least from a life
stage in one generation to the same life-stage in the next generation.
Exposure to the test material should begin with immature juveniles at
least two months prior to active gonad development, continue through
maturation and reproduction, and end not less than 24 days (90 days for
salmonids) after the hatching of the next generation. Data should be
obtained and analyzed on survival and growth of adults and young,
maturation of males and females, eggs spawned per female, embryo
viability (salmonids only), and hatchability.
3. Early life-stage toxicity tests consisting of 28- to 32-day (60
days post hatch for salmonids) exposures of the early life stages of a
species of fish from shortly after fertilization through embryonic,
larval, and early juvenile development. Data should be obtained and
analyzed on survival and growth.
Note: Results of an early life-stage test are used as predictions of
results of life-cycle and partial life-cycle tests with the same
species. Therefore, when results of a life-cycle or partial life-cycle
test are available, results of an early life-stage test with the same
species should not be used. Also, results of early life-stage tests in
which the incidence of mortalities or abnormalities increased
substantially near the end of the test shall not be used because the
results of such tests are possibly not good predictions of comparable
life-cycle or partial life-cycle tests.
F. A chronic value may be obtained by calculating the geometric mean
of the lower and upper chronic limits from a chronic test or by
analyzing chronic data using regression analysis.
1. A lower chronic limit is the highest tested concentration:
a. In an acceptable chronic test;
b. Which did not cause an unacceptable amount of adverse effect on
any of the specified biological measurements; and
c. Below which no tested concentration caused an unacceptable
effect.
2. An upper chronic limit is the lowest tested concentration:
a. In an acceptable chronic test;
b. Which did cause an unacceptable amount of adverse effect on one
or more of the specified biological measurements; and,
[[Page 501]]
c. Above which all tested concentrations also caused such an effect.
Note: Because various authors have used a variety of terms and
definitions to interpret and report results of chronic tests, reported
results should be reviewed carefully. The amount of effect that is
considered unacceptable is often based on a statistical hypothesis test,
but might also be defined in terms of a specified percent reduction from
the controls. A small percent reduction (e.g., three percent) might be
considered acceptable even if it is statistically significantly
different from the control, whereas a large percent reduction (e.g., 30
percent) might be considered unacceptable even if it is not
statistically significant.
G. If the chronic toxicity of the material to aquatic animals has
been shown to be related to a water quality characteristic such as
hardness or particulate matter for freshwater animals, refer to section
VII of this appendix.
H. If chronic values are available for species in eight families as
described in section III.B.1 of this appendix, a SMCV shall be
calculated for each species for which at least one chronic value is
available by calculating the geometric mean of the results of all
acceptable life-cycle and partial life-cycle toxicity tests with the
species; for a species of fish for which no such result is available,
the SMCV is the geometric mean of all acceptable early life-stage tests.
Appropriate GMCVs shall also be calculated. A GMCV is the geometric mean
of the SMCVs for the genus. The FCV shall be obtained using the
procedure described in sections IV.J through IV.O of this appendix,
substituting SMCV and GMCV for SMAV and GMAV respectively. See section
VI.M of this appendix.
Note: Section VI.I through VI.L are for use when chronic values are
not available for species in eight taxonomic families as described in
section III.B.1 of this appendix.
I. For each chronic value for which at least one corresponding
appropriate acute value is available, calculate an ACR, using for the
numerator the geometric mean of the results of all acceptable flow-
through (except static is acceptable for daphnids and midges) acute
tests in the same dilution water in which the concentrations are
measured. For fish, the acute test(s) should be conducted with
juveniles. The acute test(s) should be part of the same study as the
chronic test. If acute tests were not conducted as part of the same
study, but were conducted as part of a different study in the same
laboratory and dilution water, then they may be used. If no such acute
tests are available, results of acute tests conducted in the same
dilution water in a different laboratory may be used. If no such acute
tests are available, an ACR shall not be calculated.
J. For each species, calculate the SMACR as the geometric mean of
all ACRs available for that species. If the minimum ACR data
requirements (as described in section III.B.2 of this appendix) are not
met with freshwater data alone, saltwater data may be used along with
the freshwater data.
K. For some materials, the ACR seems to be the same for all species,
but for other materials the ratio seems to increase or decrease as the
SMAV increases. Thus the FACR can be obtained in three ways, depending
on the data available:
1. If the species mean ACR seems to increase or decrease as the
SMAVs increase, the FACR shall be calculated as the geometric mean of
the ACRs for species whose SMAVs are close to the FAV.
2. If no major trend is apparent and the ACRs for all species are
within a factor of ten, the FACR shall be calculated as the geometric
mean of all of the SMACRs.
3. If the most appropriate SMACRs are less than 2.0, and especially
if they are less than 1.0, acclimation has probably occurred during the
chronic test. In this situation, because continuous exposure and
acclimation cannot be assured to provide adequate protection in field
situations, the FACR should be assumed to be two, so that the FCV is
equal to the Criterion Maximum Concentration (CMC). (See section X.B of
this appendix.)
If the available SMACRs do not fit one of these cases, a FACR may
not be obtained and a Tier I FCV probably cannot be calculated.
L. Calculate the FCV by dividing the FAV by the FACR.
FCV=FAV/FACR
If there is a Final Acute Equation rather than a FAV, see also section V
of this appendix.
M. If the SMCV of a commercially or recreationally important species
of the Great Lakes System is lower than the calculated FCV, then that
SMCV must be used as the FCV instead of the calculated FCV.
N. See section VIII of this appendix.
VII. Final Chronic Equation
A. A Final Chronic Equation can be derived in two ways. The
procedure described in section VII.A of this appendix will result in the
chronic slope being the same as the acute slope. The procedure described
in sections VII.B through N of this appendix will usually result in the
chronic slope being different from the acute slope.
1. If ACRs are available for enough species at enough values of the
water quality characteristic to indicate that the ACR appears to be the
same for all species and appears to be independent of the water quality
characteristic, calculate the FACR as the geometric mean of the
available SMACRs.
[[Page 502]]
2. Calculate the FCV at the selected value Z of the water quality
characteristic by dividing the FAV at Z (see section V.M of this
appendix) by the FACR.
3. Use V=pooled acute slope (see section V.M of this appendix), and
L=pooled chronic slope.
4. See section VII.M of this appendix.
B. When enough data are available to show that chronic toxicity to
at least one species is related to a water quality characteristic, the
relationship should be taken into account as described in sections C
through G below or using analysis of covariance. The two methods are
equivalent and produce identical results. The manual method described
below provides an understanding of this application of covariance
analysis, but computerized versions of covariance analysis are much more
convenient for analyzing large data sets. If two or more factors affect
toxicity, multiple regression analysis shall be used.
C. For each species for which comparable chronic toxicity values are
available at two or more different values of the water quality
characteristic, perform a least squares regression of the chronic
toxicity values on the corresponding values of the water quality
characteristic to obtain the slope and its 95 percent confidence limits
for each species.
Note: Because the best documented relationship is that between
hardness and acute toxicity of metals in fresh water and a log-log
relationship fits these data, geometric means and natural logarithms of
both toxicity and water quality are used in the rest of this section.
For relationships based on other water quality characteristics, such as
Ph, temperature, no transformation or a different transformation might
fit the data better, and appropriate changes will be necessary
throughout this section. It is probably preferable, but not necessary,
to use the same transformation that was used with the acute values in
section V of this appendix.
D. Decide whether the data for each species are relevant, taking
into account the range and number of the tested values of the water
quality characteristic and the degree of agreement within and between
species. For example, a slope based on six data points might be of
limited value if it is based only on data for a very narrow range of
values of the water quality characteristic. A slope based on only two
data points, however, might be more useful if it is consistent with
other information and if the two points cover a broad range of the water
quality characteristic. In addition, chronic values that appear to be
questionable in comparison with other acute and chronic data available
for the same species and for other species in the same genus in most
cases should not be used. For example, if after adjustment for the water
quality characteristic, the chronic values available for a species or
genus differ by more than a factor of 10, rejection of some or all of
the values is, in most cases, absent countervailing circumstances,
appropriate. If a useful chronic slope is not available for at least one
species or if the available slopes are too dissimilar or if too few data
are available to adequately define the relationship between chronic
toxicity and the water quality characteristic, it might be appropriate
to assume that the chronic slope is the same as the acute slope, which
is equivalent to assuming that the ACR is independent of the water
quality characteristic. Alternatively, return to section VI.H of this
appendix, using the results of tests conducted under conditions and in
waters similar to those commonly used for toxicity tests with the
species.
E. Individually for each species, calculate the geometric mean of
the available chronic values and then divide each chronic value for a
species by the mean for the species. This normalizes the chronic values
so that the geometric mean of the normalized values for each species
individually, and for any combination of species, is 1.0.
F. Similarly, normalize the values of the water quality
characteristic for each species individually.
G. Individually for each species, perform a least squares regression
of the normalized chronic toxicity values on the corresponding
normalized values of the water quality characteristic. The resulting
slopes and the 95 percent confidence limits will be identical to those
obtained in section VII.B of this appendix. Now, however, if the data
are actually plotted, the line of best fit for each individual species
will go through the point 1,1 in the center of the graph.
H. Treat all of the normalized data as if they were all the same
species and perform a least squares regression of all of the normalized
chronic values on the corresponding normalized values of the water
quality characteristic to obtain the pooled chronic slope, L, and its 95
percent confidence limits.
If all normalized data are actually plotted, the line of best fit
will go through the point 1,1 in the center of the graph.
I. For each species, calculate the geometric mean, M, of the
toxicity values and the geometric mean, P, of the values of the water
quality characteristic. (These are calculated in sections VII.E and F of
this appendix.)
J. For each species, calculate the logarithm, Q, of the SMCV at a
selected value, Z, of the water quality characteristic using the
equation:
Q=ln M--L(ln P-ln Z)
Note: Although it is not necessary, it is recommended that the same
value of the water quality characteristic be used here as was used in
section V of this appendix.
K. For each species, calculate a SMCV at Z using the equation:
[[Page 503]]
SMCV=e\Q\
Note: Alternatively, the SMCV at Z can be obtained by skipping
section VII.J of this appendix, using the equations in sections VII.J
and K of this appendix to adjust each chronic value individually to Z,
and then calculating the geometric means of the adjusted values for each
species individually. This alternative procedure allows an examination
of the range of the adjusted chronic values for each species.
L. Obtain the FCV at Z by using the procedure described in sections
IV.J through O of this appendix.
M. If the SMCV at Z of a commercially or recreationally important
species of the Great Lakes System is lower than the calculated FCV at Z,
then that SMCV shall be used as the FCV at Z instead of the calculated
FCV.
N. The Final Chronic Equation is written as:
FCV=e(L&[ln(waterqualitycharacteristic)]=lnS-L[lnZ])
Where:
L=pooled chronic slope and S = FCV at Z.
Because L, S, and Z are known, the FCV can be calculated for any
selected value of the water quality characteristic.
VIII. Final Plant Value
A. A Final Plant Value (FPV) is the lowest plant value that was
obtained with an important aquatic plant species in an acceptable
toxicity test for which the concentrations of the test material were
measured and the adverse effect was biologically important. Appropriate
measures of the toxicity of the material to aquatic plants are used to
compare the relative sensitivities of aquatic plants and animals.
Although procedures for conducting and interpreting the results of
toxicity tests with plants are not well-developed, results of tests with
plants usually indicate that criteria which adequately protect aquatic
animals and their uses will, in most cases, also protect aquatic plants
and their uses.
B. A plant value is the result of a 96-hour test conducted with an
alga or a chronic test conducted with an aquatic vascular plant.
Note: A test of the toxicity of a metal to a plant shall not be used
if the medium contained an excessive amount of a complexing agent, such
as EDTA, that might affect the toxicity of the metal. Concentrations of
EDTA above 200 [micro]g/L should be considered excessive.
C. The FPV shall be obtained by selecting the lowest result from a
test with an important aquatic plant species in which the concentrations
of test material are measured and the endpoint is biologically
important.
IX. Other Data
Pertinent information that could not be used in earlier sections
might be available concerning adverse effects on aquatic organisms. The
most important of these are data on cumulative and delayed toxicity,
reduction in survival, growth, or reproduction, or any other adverse
effect that has been shown to be biologically important. Delayed
toxicity is an adverse effect to an organism that results from, and
occurs after the end of, its exposure to one or more test materials.
Especially important are data for species for which no other data are
available. Data from behavioral, biochemical, physiological, microcosm,
and field studies might also be available. Data might be available from
tests conducted in unusual dilution water (see sections IV.D and VI.D of
this appendix), from chronic tests in which the concentrations were not
measured (see section VI.B of this appendix), from tests with previously
exposed organisms (see section II.F.3 of this appendix), and from tests
on formulated mixtures or emulsifiable concentrates (see section II.D of
this appendix). Such data might affect a criterion if the data were
obtained with an important species, the test concentrations were
measured, and the endpoint was biologically important.
X. Criterion
A. A criterion consists of two concentrations: the CMC and the
Criterion Continuous Concentration (CCC).
B. The CMC is equal to one-half the FAV. The CMC is an estimate of
the highest concentration of a material in the water column to which an
aquatic community can be exposed briefly without resulting in an
unacceptable effect.
C. The CCC is equal to the lowest of the FCV or the FPV (if
available) unless other data (see section IX of this appendix) show that
a lower value should be used. The CCC is an estimate of the highest
concentration of a material in the water column to which an aquatic
community can be exposed indefinitely without resulting in an
unacceptable effect. If toxicity is related to a water quality
characteristic, the CCC is obtained from the Final Chronic Equation or
FPV (if available) that results in the lowest concentrations in the
usual range of the water quality characteristic, unless other data (see
section IX) show that a lower value should be used.
D. Round both the CMC and the CCC to two significant digits.
E. The criterion is stated as:
The procedures described in the Tier I methodology indicate that,
except possibly where a commercially or recreationally important species
is very sensitive, aquatic organisms should not be affected unacceptably
if the four-day average concentration of (1) does not exceed (2)
[micro]g/L more than once
[[Page 504]]
every three years on the average and if the one-hour average
concentration does not exceed (3) [micro]g/L more than once every three
years on the average.
Where:
(1) = insert name of material
(2) = insert the CCC
(3) = insert the CMC
If the CMC averaging period of one hour or the CCC averaging period
of four days is inappropriate for the pollutant, or if the once-in-
three-year allowable excursion frequency is inappropriate for the
pollutant or for the sites to which a criterion is applied, then the
State may specify alternative averaging periods or frequencies. The
choice of an alternative averaging period or frequency shall be
justified by a scientifically defensible analysis demonstrating that the
alternative values will protect the aquatic life uses of the water.
Appropriate laboratory data and/or well-designed field biological
surveys shall be submitted to EPA as justification for differing
averaging periods and/or frequencies of exceedance.
XI. Final Review
A. The derivation of the criterion should be carefully reviewed by
rechecking each step of the Guidance in this part. Items that should be
especially checked are:
1. If unpublished data are used, are they well documented?
2. Are all required data available?
3. Is the range of acute values for any species greater than a
factor of 10?
4. Is the range of SMAVs for any genus greater than a factor of 10?
5. Is there more than a factor of 10 difference between the four
lowest GMAVs?
6. Are any of the lowest GMAVs questionable?
7. Is the FAV reasonable in comparison with the SMAVs and GMAVs?
8. For any commercially or recreationally important species of the
Great Lakes System, is the geometric mean of the acute values from flow-
through tests in which the concentrations of test material were measured
lower than the FAV?
9. Are any of the chronic values used questionable?
10. Are any chronic values available for acutely sensitive species?
11. Is the range of acute-chronic ratios greater than a factor of
10?
12. Is the FCV reasonable in comparison with the available acute and
chronic data?
13. Is the measured or predicted chronic value for any commercially
or recreationally important species of the Great Lakes System below the
FCV?
14. Are any of the other data important?
15. Do any data look like they might be outliers?
16. Are there any deviations from the Guidance in this part? Are
they acceptable?
B. On the basis of all available pertinent laboratory and field
information, determine if the criterion is consistent with sound
scientific evidence. If it is not, another criterion, either higher or
lower, shall be derived consistent with the Guidance in this part.
Methodology for Deriving Aquatic Life Values: Tier II
XII. Secondary Acute Value
If all eight minimum data requirements for calculating an FAV using
Tier I are not met, a Secondary Acute Value (SAV) for the waters of the
Great Lakes System shall be calculated for a chemical as follows:
To calculate a SAV, the lowest GMAV in the database is divided by
the Secondary Acute Factor (SAF) (Table A-1 of this appendix)
corresponding to the number of satisfied minimum data requirements
listed in the Tier I methodology (section III.B.1 of this appendix).
(Requirements for definitions, data collection and data review,
contained in sections I, II, and IV shall be applied to calculation of a
SAV.) If all eight minimum data requirements are satisfied, a Tier I
criterion calculation may be possible. In order to calculate a SAV, the
database must contain, at a minimum, a genus mean acute value (GMAV) for
one of the following three genera in the family Daphnidae--Ceriodaphnia
sp., Daphnia sp., or Simocephalus sp.
If appropriate, the SAV shall be made a function of a water quality
characteristic in a manner similar to that described in Tier I.
XIII. Secondary Acute-Chronic Ratio
If three or more experimentally determined ACRs, meeting the data
collection and review requirements of Section VI of this appendix, are
available for the chemical, determine the FACR using the procedure
described in Section VI. If fewer than three acceptable experimentally
determined ACRs are available, use enough assumed ACRs of 18 so that the
total number of ACRs equals three. Calculate the Secondary Acute-Chronic
Ratio (SACR) as the geometric mean of the three ACRs. Thus, if no
experimentally determined ACRs are available, the SACR is 18.
XIV. Secondary Chronic Value
Calculate the Secondary Chronic Value (SCV) using one of the
following:
[[Page 505]]
[GRAPHIC] [TIFF OMITTED] TR23MR95.099
If appropriate, the SCV will be made a function of a water quality
characteristic in a manner similar to that described in Tier I.
XV. Commercially or Recreationally Important Species
If for a commercially or recreationally important species of the
Great Lakes System the geometric mean of the acute values or chronic
values from flow-through tests in which the concentrations of the test
materials were measured is lower than the calculated SAV or SCV, then
that geometric mean must be used as the SAV or SCV instead of the
calculated SAV or SCV.
XVI. Tier II Value
A. A Tier II value shall consist of two concentrations: the
Secondary Maximum Concentration (SMC) and the Secondary Continuous
Concentration (SCC).
B. The SMC is equal to one-half of the SAV.
C. The SCC is equal to the lowest of the SCV or the Final Plant
Value, if available, unless other data (see section IX of this appendix)
show that a lower value should be used.
If toxicity is related to a water quality characteristic, the SCC is
obtained from the Secondary Chronic Equation or FPV, if available, that
results in the lowest concentrations in the usual range of the water
quality characteristic, unless other data (See section IX of this
appendix) show that a lower value should be used.
D. Round both the SMC and the SCC to two significant digits.
E. The Tier II value is stated as:
The procedures described in the Tier II methodology indicate that,
except possibly where a locally important species is very sensitive,
aquatic organisms should not be affected unacceptably if the four-day
average concentration of (1) does not exceed (2) [micro]g/L more than
once every three years on the average and if the one-hour average
concentration does not exceed (3) [micro]g/L more than once every three
years on the average.
Where:
(1) = insert name of material
(2) = insert the SCC
(3) = insert the SMC
As discussed above, States and Tribes have the discretion to specify
alternative averaging periods or frequencies (see section X.E. of this
appendix).
XVII. Appropriate Modifications
On the basis of all available pertinent laboratory and field
information, determine if the Tier II value is consistent with sound
scientific evidence. If it is not, another value, either higher or
lower, shall be derived consistent with the Guidance in this part.
Table A-1--Secondary Acute Factors
------------------------------------------------------------------------
Adjustment
Number of minimum data requirements satisfied factor
------------------------------------------------------------------------
1........................................................... 21.9
2........................................................... 13.0
3........................................................... 8.0
4........................................................... 7.0
5........................................................... 6.1
6........................................................... 5.2
7........................................................... 4.3
------------------------------------------------------------------------
Appendix B to Part 132--Great Lakes Water Quality Initiative
Methodology for Deriving Bioaccumulation Factors
Great Lakes States and Tribes shall adopt provisions consistent with
(as protective as) this appendix.
I. Introduction
A. The purpose of this methodology is to describe procedures for
deriving bioaccumulation factors (BAFs) to be used in the calculation of
Great Lakes Water Quality Guidance (Guidance) human health Tier I
criteria and Tier II values and wildlife Tier I criteria. A subset of
the human health BAFs are also used to identify the chemicals that are
considered bioaccumulative chemicals of concern (BCCs).
B. Bioaccumulation reflects uptake of a substance by aquatic
organisms exposed to the substance through all routes (i.e., ambient
water and food), as would occur in nature. Bioconcentration reflects
uptake of a substance by aquatic organisms exposed to the substance only
through the ambient water. Both BAFs and bioconcentration factors (BCFs)
are proportionality constants that describe the relationship between the
concentration of a substance in aquatic organisms and its concentration
in the ambient water. For the Guidance in this part, BAFs, rather than
BCFs, are used to calculate Tier I criteria for human health and
wildlife and Tier II values for human health because they
[[Page 506]]
better account for the total exposure of aquatic organisms to chemicals.
C. For organic chemicals, baseline BAFs can be derived using four
methods. Measured baseline BAFs are derived from field-measured BAFs;
predicted baseline BAFs are derived using biota-sediment accumulation
factors (BSAFs) or are derived by multiplying a laboratory-measured or
predicted BCF by a food-chain multiplier (FCM). The lipid content of the
aquatic organisms is used to account for partitioning of organic
chemicals within organisms so that data from different tissues and
species can be integrated. In addition, the baseline BAF is based on the
concentration of freely dissolved organic chemicals in the ambient water
to facilitate extrapolation from one water to another.
D. For inorganic chemicals, baseline BAFs can be derived using two
of the four methods. Baseline BAFs are derived using either field-
measured BAFs or by multiplying laboratory-measured BCFs by a FCM. For
inorganic chemicals, BAFs are assumed to equal BCFs (i.e., the FCM is
1.0), unless chemical-specific biomagnification data support using a FCM
other than 1.0.
E. Because both humans and wildlife consume fish from both trophic
levels 3 and 4, two baseline BAFs are needed to calculate either a human
health criterion or value or a wildlife criterion for a chemical. When
appropriate, ingestion through consumption of invertebrates, plants,
mammals, and birds in the diet of wildlife species to be protected may
be taken into account.
II. Definitions
Baseline BAF. For organic chemicals, a BAF that is based on the
concentration of freely dissolved chemical in the ambient water and
takes into account the partitioning of the chemical within the organism;
for inorganic chemicals, a BAF that is based on the wet weight of the
tissue.
Baseline BCF. For organic chemicals, a BCF that is based on the
concentration of freely dissolved chemical in the ambient water and
takes into account the partitioning of the chemical within the organism;
for inorganic chemicals, a BCF that is based on the wet weight of the
tissue.
Bioaccumulation. The net accumulation of a substance by an organism
as a result of uptake from all environmental sources.
Bioaccumulation factor (BAF). The ratio (in L/kg) of a substance's
concentration in tissue of an aquatic organism to its concentration in
the ambient water, in situations where both the organism and its food
are exposed to and the ratio does not change substantially over time.
Bioconcentration. The net accumulation of a substance by an aquatic
organism as a result of uptake directly from the ambient water through
gill membranes or other external body surfaces.
Bioconcentration factor (BCF). The ratio (in L/kg) of a substance's
concentration in tissue of an aquatic organism to its concentration in
the ambient water, in situations where the organism is exposed through
the water only and the ratio does not change substantially over time.
Biota-sediment accumulation factor (BSAF). The ratio (in kg of
organic carbon/kg of lipid) of a substance's lipid-normalized
concentration in tissue of an aquatic organism to its organic carbon-
normalized concentration in surface sediment, in situations where the
ratio does not change substantially over time, both the organism and its
food are exposed, and the surface sediment is representative of average
surface sediment in the vicinity of the organism.
Depuration. The loss of a substance from an organism as a result of
any active or passive process.
Food-chain multiplier (FCM). The ratio of a BAF to an appropriate
BCF.
Octanol-water partition coefficient (KOW). The ration of
the concentration of a substance in the n-octanol phase to its
concentration in the aqueous phase in an equilibrated two-phase octanol-
water system. For log KOW, the log of the octanol-water
partition coefficient is a base 10 logarithm.
Uptake. Acquisition of a substance from the environment by an
organism as a result of any active or passive process.
III. Review and Selection of Data
A. Data Sources. Measured BAFs, BSAFs and BCFs are assembled from
available sources including the following:
1. EPA Ambient Water Quality Criteria documents issued after January
1, 1980.
2. Published scientific literature.
3. Reports issued by EPA or other reliable sources.
4. Unpublished data.
One useful source of references is the Aquatic Toxicity Information
Retrieval (AQUIRE) database.
B. Field-Measured BAFs. The following procedural and quality
assurance requirements shall be met for field-measured BAFs:
1. The field studies used shall be limited to those conducted in the
Great Lakes System with fish at or near the top of the aquatic food
chain (i.e., in trophic levels 3 and/or 4).
2. The trophic level of the fish species shall be determined.
3. The site of the field study should not be so unique that the BAF
cannot be extrapolated to other locations where the criteria and values
will apply.
4. For organic chemicals, the percent lipid shall be either measured
or reliably estimated for the tissue used in the determination of the
BAF.
[[Page 507]]
5. The concentration of the chemical in the water shall be measured
in a way that can be related to particulate organic carbon (POC) and/or
dissolved organic carbon (DOC) and should be relatively constant during
the steady-state time period.
6. For organic chemicals with log KOW greater than four,
the concentrations of POC and DOC in the ambient water shall be either
measured or reliably estimated.
7. For inorganic and organic chemicals, BAFs shall be used only if
they are expressed on a wet weight basis; BAFs reported on a dry weight
basis cannot be converted to wet weight unless a conversion factor is
measured or reliably estimated for the tissue used in the determination
of the BAF.
C. Field-Measured BSAFs. The following procedural and quality
assurance requirements shall be met for field-measured BSAFs:
1. The field studies used shall be limited to those conducted in the
Great Lakes System with fish at or near the top of the aquatic food
chain (i.e., in trophic levels 3 and/or 4).
2. Samples of surface sediments (0-1 cm is ideal) shall be from
locations in which there is net deposition of fine sediment and is
representative of average surface sediment in the vicinity of the
organism.
3. The KOW s used shall be acceptable quality as
described in section III.F below.
4. The site of the field study should not be so unique that the
resulting BAF cannot be extrapolated to other locations where the
criteria and values will apply.
5. The tropic level of the fish species shall be determined.
6. The percent lipid shall be either measured or reliably estimated
for the tissue used in the determination of the BAF.
D. Laboratory-Measured BCFs. The following procedural and quality
assurance requirements shall be met for laboratory-measured BCFs:
1. The test organism shall not be diseased, unhealthy, or adversely
affected by the concentration of the chemical.
2. The total concentration of the chemical in the water shall be
measured and should be relatively constant during the steady-state time
period.
3. The organisms shall be exposed to the chemical using a flow-
through or renewal procedure.
4. For organic chemicals, the percent lipid shall be either measured
or reliably estimated for the tissue used in the determination of the
BCF.
5. For organic chemicals with log KOW greater than four,
the concentrations of POC and DOC in the test solution shall be either
measured or reliably estimated.
6. Laboratory-measured BCFs should be determined using fish species,
but BCFs determined with molluscs and other invertebrates may be used
with caution. For example, because invertebrates metabolize some
chemicals less efficiently than vertebrates, a baseline BCF determined
for such a chemical using invertebrates is expected to be higher than a
comparable baseline BCF determined using fish.
7. If laboratory-measured BCFs increase or decrease as the
concentration of the chemical increases in the test solutions in a
bioconcentration test, the BCF measured at the lowest test concentration
that is above concentrations existing in the control water shall be used
(i.e., a BCF should be calculated from a control treatment). The
concentrations of an inorganic chemical in a bioconcentration test
should be greater than normal background levels and greater than levels
required for normal nutrition of the test species if the chemical is a
micronutrient, but below levels that adversely affect the species.
Bioaccummulation of an inorganic chemical might be overestimated if
concentrations are at or below normal background levels due to, for
example, nutritional requirements of the test organisms.
8. For inorganic and organic chemicals, BCFs shall be used only if
they are expressed on a wet weight basis. BCFs reported on a dry weight
basis cannot be converted to wet weight unless a conversion factor is
measured or reliably estimated for the tissue used in the determination
of the BAF.
9. BCFs for organic chemicals may be based on measurement or
radioactivity only when the BCF is intended to include metabolites or
when there is confidence that there is no interference due to
metabolites.
10. The calculation of the BCF must appropriately address growth
dilution.
11. Other aspects of the methodology used should be similar to those
described by ASTM (1990).
E. Predicted BCFs. The following procedural and quality assurance
requirements shall be met for predicted BCFs:
1. The KOW used shall be of acceptable quality as
described in section III.F below.
2. The predicted baseline BCF shall be calculated using the
equation: predicted baseline BCF = KOW
where:
KOW = octanol-water partition coefficient.
F. Octanol-Water Partition Coefficient (KOW). 1. The
value of KOW used for an organic chemical shall be determined
by giving priority to the experimental and computational techniques used
as follows:
Log KOW < 4:
------------------------------------------------------------------------
Priority Technique
------------------------------------------------------------------------
1......................................... Slow-stir.
1......................................... Generator-column.
1......................................... Shake-flask.
2......................................... Reverse-phase liquid
chromatography on C18
chromatography packing with
extrapolation to zero
percent solvent.
[[Page 508]]
3......................................... Reverse-phase liquid
chromatography on C18
chromatography packing
without extrapolation to
zero percent solvent.
4......................................... Calculated by the CLOGP
program.
------------------------------------------------------------------------
Log KOW 4:
------------------------------------------------------------------------
Priority Technique
------------------------------------------------------------------------
1................................. Slow Stir.
1................................. Generator-column.
2................................. Reverse-phase liquid chromatography
on C18 chromatography packing with
extrapolation to zero percent
solvent.
3................................. Reverse-phase liquid chromatography
on C18 chromatography packing
without extrapolation to zero
percent solvent.
4................................. Shake-flask.
5................................. Calculated by the CLOGP program.
------------------------------------------------------------------------
2. The CLOGP program is a computer program available from Pomona
College. A value of KOW that seems to be different from the
others should be considered an outlier and not used. The value of
KOW used for an organic chemical shall be the geometric mean
of the available KOW s with highest priority or can be
calculated from the arithmetic mean of the available log KOW
with the highest priority. Because it is an intermediate value in the
derivation of a BAF, the value used for the KOW of a chemical
should not be rounded to fewer than three significant digits and a value
for log KOW should not be rounded to fewer than three
significant digits after the decimal point.
G. This methodology provides overall guidance for the derivation of
BAFs, but it cannot cover all the decisions that must be made in the
review and selection of acceptable data. Professional judgment is
required throughout the process. A degree of uncertainty is associated
with the determination of any BAF, BSAF, BCF or KOW. The
amount of uncertainty in a baseline BAF depends on both the quality of
data available and the method used to derive the BAF.
H. Hereinafter in this methodology, the terms BAF, BSAF, BCF and
KOW refer to ones that are consistent with the procedural and
quality assurance requirements given above.
IV. Four Methods for Deriving Baseline BAFs
Baseline BAFs shall be derived using the following four methods,
which are listed from most preferred to least preferred:
A. A measured baseline BAF for an organic or inorganic chemical
derived from a field study of acceptable quality.
B. A predicted baseline BAF for an organic chemical derived using
field-measured BSAFs of acceptable quality.
C. A predicted baseline BAF for an organic or inorganic chemical
derived from a BCF measured in a laboratory study of acceptable quality
and a FCM.
D. A predicted baseline BAF for an organic chemical derived from a
KOW of acceptable quality and a FCM.
For comparative purposes, baseline BAFs should be derived for each
chemical by as many of the four methods as available data allow.
V. Calculation of Baseline BAFs for Organic Chemicals
A. Lipid Normalization. 1. It is assumed that BAFs and BCFs for
organic chemicals can be extrapolated on the basis of percent lipid from
one tissue to another and from one aquatic species to another in most
cases.
2. Because BAFs and BCFs for organic chemicals are related to the
percent lipid, it does not make any difference whether the tissue sample
is whole body or edible portion, but both the BAF (or BCF) and the
percent lipid must be determined for the same tissue. The percent lipid
of the tissue should be measured during the BAF or BCF study, but in
some cases it can be reliably estimated from measurements on tissue from
other organisms. If percent lipid is not reported for the test organisms
in the original study, it may be obtained from the author; or, in the
case of a laboratory study, lipid data for the same or a comparable
laboratory population of test organisms that were used in the original
study may be used.
3. The lipid-normalized concentration, Cl, of a chemical
in tissue is defined using the following equation:
[GRAPHIC] [TIFF OMITTED] TR23MR95.100
Where:
CB=concentration of the organic chemical in the tissue of
aquatic biota (either whole organism or specified tissue) ([micro]g/g).
fl=fraction of the tissue that is lipid.
B. Bioavailability. By definition, baseline BAFs and BCFs for
organic chemicals, whether measured or predicted are based on the
concentration of the chemical that is freely dissolved in the ambient
water in order to account for bioavailability. For the purposes of this
Guidance in this part, the relationship between the total concentration
of the chemical in the water (i.e., that which is freely dissolved plus
that which is sorbed to particulate organic carbon or to dissolved
organic carbon) to the freely dissolved concentration of the chemical in
the ambient water shall be calculated using the following equation:
[[Page 509]]
[GRAPHIC] [TIFF OMITTED] TR23MR95.101
Where:
C\fd\w=freely dissolved concentration of the organic chemical
in the ambient water;
C\t\w=total concentration of the organic chemical in the
ambient water;
ffd=fraction of the total chemical in the ambient water that
is freely dissolved.
The fraction of the total chemical in the ambient water that is
freely dissolved, ffd, shall be calculated using the
following equation:
[GRAPHIC] [TIFF OMITTED] TR23MR95.102
Where:
DOC=concentration of dissolved organic carbon, kg of dissolved organic
carbon/L of water.
KOW=octanol-water partition coefficient of the chemical.
POC=concentration of particulate organic carbon, kg of particulate
organic carbon/L of water.
C. Food-Chain Multiplier. In the absence of a field-measured BAF or
a predicted BAF derived from a BSAF, a FCM shall be used to calculate
the baseline BAF for trophic levels 3 and 4 from a laboratory-measured
or predicted BCF. For an organic chemical, the FCM used shall be derived
from Table B-1 using the chemical's log KOW and linear
interpolation. A FCM greater than 1.0 applies to most organic chemicals
with a log KOW of four or more. The trophic level used shall
take into account the age or size of the fish species consumed by the
human, avian or mammalian predator because, for some species of fish,
the young are in trophic level 3 whereas the adults are in trophic level
4.
D. Calculation of a Baseline BAF from a Field-Measured BAF. A
baseline BAF shall be calculated from a field-measured BAF of acceptable
quality using the following equation:
[GRAPHIC] [TIFF OMITTED] TR23MR95.103
Where:
BAF\t\T=BAF based on total concentration in tissue and water.
fl=fraction of the tissue that is lipid.
ffd=fraction of the total chemical that is freely dissolved
in the ambient water.
The trophic level to which the baseline BAF applies is the same as the
trophic level of the organisms used in the determination of the field-
measured BAF. For each trophic level, a species mean measured baseline
BAF shall be calculated as the geometric mean if more than one measured
baseline BAF is available for a given species. For each trophic level,
the geometric mean of the species mean measured baseline BAFs shall be
calculated. If a baseline BAF based on a measured BAF is available for
either trophic level 3 or 4, but not both, a measured baseline BAF for
the other trophic level shall be calculated using the ratio of the FCMs
that are obtained by linear interpolation from Table B-1 for the
chemical.
E. Calculation of a Baseline BAF from a Field-Measured BSAF. 1. A
baseline BAF for organic chemical ``i'' shall be calculated from a
field-measured BSAF of acceptable quality using the following equation:
[GRAPHIC] [TIFF OMITTED] TR23MR95.105
Where:
(BSAF)i=BSAF for chemical ``i''.
(BSAF)r=BSAF for the reference chemical ``r''.
(KOW)i=octanol-water partition coefficient for
chemical ``i''.
(KOW)r=octanol-water partition coefficient for the
reference chemical ``r''.
2. A BSAF shall be calculated using the following equation:
[[Page 510]]
[GRAPHIC] [TIFF OMITTED] TR23MR95.106
Where:
Ct=the lipid-normalized concentration of the chemical in
tissue.
CSOC=the organic carbon-normalized concentration of the
chemical in sediment.
3. The organic carbon-normalized concentration of a chemical in
sediment, CSOC, shall be calculated using the following
equation:
[GRAPHIC] [TIFF OMITTED] TR23MR95.107
Where:
CS=concentration of chemical in sediment ([micro]g/g
sediment).
fOC=fraction of the sediment that is organic carbon.
4. Predicting BAFs from BSAFs requires data from a steady-state (or
near steady-state) condition between sediment and ambient water for both
a reference chemical ``r'' with a field-measured BAFl fd and
other chemicals ``n=i'' for which BSAFs are to be determined.
5. The trophic level to which the baseline BAF applies is the same
as the trophic level of the organisms used in the determination of the
BSAF. For each trophic level, a species mean baseline BAF shall be
calculated as the geometric mean if more than one baseline BAF is
predicted from BSAFs for a given species. For each trophic level, the
geometric mean of the species mean baseline BAFs derived using BSAFs
shall be calculated.
6. If a baseline BAF based on a measured BSAF is available for
either trophic level 3 or 4, but not both, a baseline BAF for the other
trophic level shall be calculated using the ratio of the FCMs that are
obtained by linear interpolation from Table B-1 for the chemical.
F. Calculation of a Baseline BAF from a Laboratory-Measured BCF. A
baseline BAF for trophic level 3 and a baseline BAF for trophic level 4
shall be calculated from a laboratory-measured BCF of acceptable quality
and a FCM using the following equation:
[GRAPHIC] [TIFF OMITTED] TR23MR95.108
Where:
BCF\t\T=BCF based on total concentration in tissue and water.
fl=fraction of the tissue that is lipid.
ffd=fraction of the total chemical in the test water that is
freely dissolved.
FCM=the food-chain multiplier obtained from Table B-1 by linear
interpolation for trophic level 3 or 4, as necessary.
For each trophic level, a species mean baseline BAF shall be calculated
as the geometric mean if more than one baseline BAF is predicted from
laboratory-measured BCFs for a given species. For each trophic level,
the geometric mean of the species mean baseline BAFs based on
laboratory-measured BCFs shall be calculated.
G. Calculation of a Baseline BAF from an Octanol-Water Partition
Coefficient. A baseline BAF for trophic level 3 and a baseline BAF for
trophic level 4 shall be calculated from a KOW of acceptable
quality and a FCM using the following equation:
Baseline BAF=(FCM) (predicted baseline BCF)=(FCM) (KOW)
Where:
FCM=the food-chain multiplier obtained from Table B-1 by linear
interpolation for trophic level 3 or 4, as necessary.
KOW=octanol-water partition coefficient.
VI. Human Health and Wildlife BAFs for Organic Chemicals
A. To calculate human health and wildlife BAFs for an organic
chemical, the KOW of the chemical shall be used with a POC
concentration of 0.00000004 kg/L and a DOC concentration of 0.000002 kg/
L to yield the fraction freely dissolved:
[[Page 511]]
[GRAPHIC] [TIFF OMITTED] TR23MR95.109
B. The human health BAFs for an organic chemical shall be calculated
using the following equations:
For trophic level 3:
[GRAPHIC] [TIFF OMITTED] TR23MR95.110
For trophic level 4:
[GRAPHIC] [TIFF OMITTED] TR23MR95.111
Where:
0.0182 and 0.0310 are the standardized fraction lipid values for
trophic levels 3 and 4, respectively, that are used to derive human
health criteria and values for the GLI.
C. The wildlife BAFs for an organic chemical shall be calculated
using the following equations:
For trophic level 3:
[GRAPHIC] [TIFF OMITTED] TR23MR95.112
For trophic level 4:
[GRAPHIC] [TIFF OMITTED] TR23MR95.113
Where:
0.0646 and 0.1031 are the standardized fraction lipid values for
trophic levels 3 and 4, respectively, that are used to derive wildlife
criteria for the GLI.
VII. Human Health and Wildlife BAFs for Inorganic Chemicals
A. For inorganic chemicals, the baseline BAFs for trophic levels 3
and 4 are both assumed to equal the BCF determined for the chemical with
fish, i.e., the FCM is assumed
[[Page 512]]
to be 1 for both trophic levels 3 and 4. However, a FCM greater than 1
might be applicable to some metals, such as mercury, if, for example, an
organometallic form of the metal biomagnifies.
B. BAFs for Human Health Criteria and Values.
1. Measured BAFs and BCFs used to determine human health BAFs for
inorganic chemicals shall be based on edible tissue (e.g., muscle) of
freshwater fish unless it is demonstrated that whole-body BAFs or BCFs
are similar to edible-tissue BAFs or BCFs. BCFs and BAFs based on
measurements of aquatic plants and invertebrates should not be used in
the derivation of human health criteria and values.
2. If one or more field-measured baseline BAFs for an inorganic
chemical are available from studies conducted in the Great Lakes System
with the muscle of fish:
a. For each trophic level, a species mean measured baseline BAF
shall be calculated as the geometric mean if more than one measured BAF
is available for a given species; and
b. For each trophic level, the geometric mean of the species mean
measured baseline BAFs shall be used as the human health BAF for that
chemical.
3. If an acceptable measured baseline BAF is not available for an
inorganic chemical and one or more acceptable edible-portion laboratory-
measured BCFs are available for the chemical, a predicted baseline BAF
shall be calculated by multiplying the geometric mean of the BCFs times
a FCM. The FCM will be 1.0 unless chemical-specific biomagnification
data support using a multiplier other than 1.0. The predicted baseline
BAF shall be used as the human health BAF for that chemical.
C. BAFs for Wildlife Criteria.
1. Measured BAFs and BCFs used to determine wildlife BAFs for
inorganic chemicals shall be based on whole-body freshwater fish and
invertebrate data unless it is demonstrated that edible-tissue BAFs or
BCFs are similar to whole-body BAFs or BCFs.
2. If one or more field-measured baseline BAFs for an inorganic
chemical are available from studies conducted in the Great Lakes System
with whole body of fish or invertebrates:
a. For each trophic level, a species mean measured baseline BAF
shall be calculated as the geometric mean if more than one measured BAF
is available for a given species.
b. For each trophic level, the geometric mean of the species mean
measured baseline BAFs shall be used as the wildlife BAF for that
chemical.
3. If an acceptable measured baseline BAF is not available for an
inorganic chemical and one or more acceptable whole-body laboratory-
measured BCFs are available for the chemical, a predicted baseline BAF
shall be calculated by multiplying the geometric mean of the BCFs times
a FCM. The FCM will be 1.0 unless chemical-specific biomagnification
data support using a multiplier other than 1.0. The predicted baseline
BAF shall be used as the wildlife BAF for that chemical.
VIII. Final Review
For both organic and inorganic chemicals, human health and wildlife
BAFs for both trophic levels shall be reviewed for consistency with all
available data concerning the bioaccumulation, bioconcentration, and
metabolism of the chemical. For example, information concerning octanol-
water partitioning, molecular size, or other physicochemical properties
that might enhance or inhibit bioaccumulation should be considered for
organic chemicals. BAFs derived in accordance with this methodology
should be modified if changes are justified by available data.
IX. Literature Cited
ASTM. 1990. Standard Practice for Conducting Bioconcentration Tests
with Fishes and Saltwater Bivalve Molluscs. Standard E 1022. American
Society for Testing and Materials, Philadelphia, PA.
Table B-1--Food-Chain Multipliers for Trophic Levels 2, 3 & 4
------------------------------------------------------------------------
Trophic Trophic\1\ Trophic
Log KOW level 2 level 3 level 4
------------------------------------------------------------------------
2.0.............................. 1.000 1.005 1.000
2.5.............................. 1.000 1.010 1.002
3.0.............................. 1.000 1.028 1.007
3.1.............................. 1.000 1.034 1.007
3.2.............................. 1.000 1.042 1.009
3.3.............................. 1.000 1.053 1.012
3.4.............................. 1.000 1.067 1.014
3.5.............................. 1.000 1.083 1.019
3.6.............................. 1.000 1.103 1.023
3.7.............................. 1.000 1.128 1.033
3.8.............................. 1.000 1.161 1.042
3.9.............................. 1.000 1.202 1.054
4.0.............................. 1.000 1.253 1.072
4.1.............................. 1.000 1.315 1.096
4.2.............................. 1.000 1.380 1.130
4.3.............................. 1.000 1.491 1.178
4.4.............................. 1.000 1.614 1.242
4.5.............................. 1.000 1.766 1.334
4.6.............................. 1.000 1.950 1.459
4.7.............................. 1.000 2.175 1.633
4.8.............................. 1.000 2.452 1.871
4.9.............................. 1.000 2.780 2.193
5.0.............................. 1.000 3.181 2.612
5.1.............................. 1.000 3.643 3.162
5.2.............................. 1.000 4.188 3.873
5.3.............................. 1.000 4.803 4.742
5.4.............................. 1.000 5.502 5.821
5.5.............................. 1.000 6.266 7.079
5.6.............................. 1.000 7.096 8.551
5.7.............................. 1.000 7.962 10.209
5.8.............................. 1.000 8.841 12.050
5.9.............................. 1.000 9.716 13.964
6.0.............................. 1.000 10.556 15.996
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6.1.............................. 1.000 11.337 17.783
6.2.............................. 1.000 12.064 19.907
6.3.............................. 1.000 12.691 21.677
6.4.............................. 1.000 13.228 23.281
6.5.............................. 1.000 13.662 24.604
6.6.............................. 1.000 13.980 25.645
6.7.............................. 1.000 14.223 26.363
6.8.............................. 1.000 14.355 26.669
6.9.............................. 1.000 14.388 26.669
7.0.............................. 1.000 14.305 26.242
7.1.............................. 1.000 14.142 25.468
7.2.............................. 1.000 13.852 24.322
7.3.............................. 1.000 13.474 22.856
7.4.............................. 1.000 12.987 21.038
7.5.............................. 1.000 12.517 18.967
7.6.............................. 1.000 11.708 16.749
7.7.............................. 1.000 10.914 14.388
7.8.............................. 1.000 10.069 12.050
7.9.............................. 1.000 9.162 9.840
8.0.............................. 1.000 8.222 7.798
8.1.............................. 1.000 7.278 6.012
8.2.............................. 1.000 6.361 4.519
8.3.............................. 1.000 5.489 3.311
8.4.............................. 1.000 4.683 2.371
8.5.............................. 1.000 3.949 1.663
8.6.............................. 1.000 3.296 1.146
8.7.............................. 1.000 2.732 0.778
8.8.............................. 1.000 2.246 0.521
8.9.............................. 1.000 1.837 0.345
9.0.............................. 1.000 1.493 0.226
------------------------------------------------------------------------
\1\ The FCMs for trophic level 3 are the geometric mean of the FCMs for
sculpin and alewife.
Appendix C to Part 132--Great Lakes Water Quality Initiative
Methodologies for Development of Human Health Criteria and Values
Great Lakes States and Tribes shall adopt provisions consistent with
(as protective as) this appendix.
I. Introduction
Great Lakes States and Tribes shall adopt provisions consistent with
this appendix C to ensure protection of human health.
A. Goal. The goal of the human health criteria for the Great Lakes
System is the protection of humans from unacceptable exposure to
toxicants via consumption of contaminated fish and drinking water and
from ingesting water as a result of participation in water-oriented
recreational activities.
B. Definitions.
Acceptable daily exposure (ADE). An estimate of the maximum daily
dose of a substance which is not expected to result in adverse noncancer
effects to the general human population, including sensitive subgroups.
Adverse effect. Any deleterious effect to organisms due to exposure
to a substance. This includes effects which are or may become
debilitating, harmful or toxic to the normal functions of the organism,
but does not include non-harmful effects such as tissue discoloration
alone or the induction of enzymes involved in the metabolism of the
substance.
Carcinogen. A substance which causes an increased incidence of
benign or malignant neoplasms, or substantially decreases the time to
develop neoplasms, in animals or humans. The classification of
carcinogens is discussed in section II.A of appendix C to part 132.
Human cancer criterion (HCC). A Human Cancer Value (HCV) for a
pollutant that meets the minimum data requirements for Tier I specified
in appendix C.
Human cancer value (HCV). The maximum ambient water concentration of
a substance at which a lifetime of exposure from either: drinking the
water, consuming fish from the water, and water-related recreation
activities; or consuming fish from the water, and water-related
recreation activities, will represent a plausible upper-bound risk of
contracting cancer of one in 100,000 using the exposure assumptions
specified in the Methodologies for the Development of Human Health
Criteria and Values in appendix C of this part.
Human noncancer criterion (HNC). A Human Noncancer Value (HNV) for a
pollutant that meets the minimum data requirements for Tier I specified
in appendix C of this part.
Human noncancer value (HNV). The maximum ambient water concentration
of a substance at which adverse noncancer effects are not likely to
occur in the human population from lifetime exposure via either:
drinking the water, consuming fish from the water, and water-related
recreation activities; or consuming fish from the water, and water-
related recreation activities using the Methodologies for the
Development of Human Health criteria and Values in appendix C of this
part.
Linearized multi-stage model. A conservative mathematical model for
cancer risk assessment. This model fits linear dose-response curves to
low doses. It is consistent with a no-threshold model of carcinogenesis,
i.e., exposure to even a very small amount of the substance is assumed
to produce a finite increased risk of cancer.
Lowest observed adverse effect level (LOAEL). The lowest tested dose
or concentration of a substance which resulted in an observed adverse
effect in exposed test organisms when all higher doses or concentrations
resulted in the same or more severe effects.
No observed adverse effect level (NOAEL). The highest tested dose or
concentration of a substance which resulted in no observed adverse
effect in exposed test organisms where higher doses or concentrations
resulted in an adverse effect.
Quantitative structure activity relationship (OSAR) or structure
activity relationship (SAR). A mathematical relationship between a
[[Page 514]]
property (activity) of a chemical and a number of descriptors of the
chemical. These descriptors are chemical or physical characteristics
obtained experimentally or predicted from the structure of the chemical.
Relative source contribution (RSC). The factor (percentage) used in
calculating an HNV or HNC to account for all sources of exposure to a
contaminant. The RSC reflects the percent of total exposure which can be
attributed to surface water through water intake and fish consumption.
Risk associated dose (RAD). A dose of a known or presumed
carcinogenic substance in (mg/kg/day) which, over a lifetime of
exposure, is estimated to be associated with a plausible upper bound
incremental cancer risk equal to one in 100,000.
Slope factor. Also known as q1*, slope factor is the
incremental rate of cancer development calculated through use of a
linearized multistage model or other appropriate model. It is expressed
in (mg/kg/day) of exposure to the chemical in question.
Threshold effect. An effect of a substance for which there is a
theoretical or empirically established dose or concentration below which
the effect does not occur.
Uncertainty factor (UF). One of several numeric factors used in
operationally deriving criteria from experimental data to account for
the quality or quantity of the available data.
C. Level of Protection. The criteria developed shall provide a level
of protection likely to be without appreciable risk of carcinogenic and/
or noncarcinogenic effects. Criteria are a function of the level of
designated risk or no adverse effect estimation, selection of data and
exposure assumptions. Ambient criteria for single carcinogens shall not
be set at a level representing a lifetime upper-bound incremental risk
greater than one in 100,000 of developing cancer using the hazard
assessment techniques and exposure assumptions described herein.
Criteria affording protection from noncarcinogenic effects shall be
established at levels that, taking into account uncertainties, are
considered likely to be without an appreciable risk of adverse human
health effects (i.e., acute, subchronic and chronic toxicity including
reproductive and developmental effects) during a lifetime of exposure,
using the risk assessment techniques and exposure assumptions described
herein.
D. Two-tiered Classification. Chemical concentration levels in
surface water protective of human health shall be derived based on
either a Tier I or Tier II classification. The two Tiers are primarily
distinguished by the amount of toxicity data available for deriving the
concentration levels and the quantity and quality of data on
bioaccumulation.
II. Minimum Data Requirements
The best available toxicity data on the adverse health effects of a
chemical and the best data on bioaccumulation factors shall be used when
developing human health Tier I criteria or Tier II values. The best
available toxicity data shall include data from well-conducted
epidemiologic and/or animal studies which provide, in the case of
carcinogens, an adequate weight of evidence of potential human
carcinogenicity and, in the case of noncarcinogens, a dose-response
relationship involving critical effects biologically relevant to humans.
Such information should be obtained from the EPA Integrated Risk
Information System (IRIS) database, the scientific literature, and other
informational databases, studies and/or reports containing adverse
health effects data of adequate quality for use in this procedure.
Strong consideration shall be given to the most currently available
guidance provided by IRIS in deriving criteria or values, supplemented
with any recent data not incorporated into IRIS. When deviations from
IRIS are anticipated or considered necessary, it is strongly recommended
that such actions be communicated to the EPA Reference Dose (RfD) and/or
the Cancer Risk Assessment Verification Endeavor (CRAVE) workgroup
immediately. The best available bioaccumulation data shall include data
from field studies and well-conducted laboratory studies.
A. Carcinogens. Tier I criteria and Tier II values shall be derived
using the methodologies described in section III.A of this appendix when
there is adequate evidence of potential human carcinogenic effects for a
chemical. It is strongly recommended that the EPA classification system
for chemical carcinogens, which is described in the 1986 EPA Guidelines
for Carcinogenic Risk Assessment (U.S. EPA, 1986), or future
modifications thereto, be used in determining whether adequate evidence
of potential carcinogenic effects exists. Carcinogens are classified,
depending on the weight of evidence, as either human carcinogens,
probable human carcinogens, or possible human carcinogens. The human
evidence is considered inadequate and therefore the chemical cannot be
classified as a human carcinogen, if one of two conditions exists: (a)
there are few pertinent data, or (b) the available studies, while
showing evidence of association, do not exclude chance, bias, or
confounding and therefore a casual interpretation is not credible. The
animal evidence is considered inadequate, and therefore the chemical
cannot be classified as a probable or possible human carcinogen, when,
because of major qualitative or quantitative limitations, the evidence
cannot be interpreted as showing either the presence or absence of a
carcinogenic effect.
[[Page 515]]
Chemicals are described as ``human carcinogens'' when there is
sufficient evidence from epidemiological studies to support a causal
association between exposure to the chemicals and cancer. Chemicals
described as ``probable human carcinogens'' include chemicals for which
the weight of evidence of human carcinogenicity based on epidemiological
studies is limited. Limited human evidence is that which indicates that
a causal interpretation is credible, but that alternative explanations,
such as chance, bias, or confounding, cannot adequately be excluded.
Probable human carcinogens are also agents for which there is sufficient
evidence from animal studies and for which there is inadequate evidence
or no data from epidemiologic studies. Sufficient animal evidence is
data which indicates that there is an increased incidence of malignant
tumors or combined malignant and benign tumors: (a) in multiple species
or strains; (b) in multiple experiments (e.g., with different routes of
administration or using different dose levels); or (c) to an unusual
degree in a single experiment with regard to high incidence, unusual
site or type of tumor, or early age at onset. Additional evidence may be
provided by data on dose-response effects, as well as information from
short-term tests (such as mutagenicity/genotoxicity tests which help
determine whether the chemical interacts directly with DNA) or on
chemical structure, metabolism or mode of action.
``Possible human carcinogens'' are chemicals with limited evidence
of carcinogenicity in animals in the absence of human data. Limited
animal evidence is defined as data which suggests a carcinogenic effect
but are limited because: (a) The studies involve a single species,
strain, or experiment and do not meet criteria for sufficient evidence
(see preceding paragraph); or (b) the experiments are restricted by
inadequate dosage levels, inadequate duration of exposure to the agent,
inadequate period of follow-up, poor survival, too few animals, or
inadequate reporting; or (c) the studies indicate an increase in the
incidence of benign tumors only. More specifically, this group can
include a wide variety of evidence, e.g., (a) a malignant tumor response
in a single well-conducted experiment that does not meet conditions for
sufficient evidence, (b) tumor response of marginal statistical
significance in studies having inadequate design or reporting, (c)
benign but not malignant tumors with an agent showing no response in a
variety of short-term tests for mutagenicity, and (d) response of
marginal statistical significance in a tissue known to have a high or
variable background rate.
1. Tier I: Weight of evidence of potential human carcinogenic
effects sufficient to derive a Tier I HCC shall generally include human
carcinogens, probable human carcinogens and can include, on a case-by-
case basis, possible human carcinogens if studies have been well-
conducted albeit based on limited evidence, when compared to studies
used in classifying human and probable human carcinogens. The decision
to use data on a possible human carcinogen for deriving Tier I criteria
shall be a case-by-case determination. In determining whether to derive
a Tier I HCC, additional evidence that shall be considered includes but
is not limited to available information on mode of action, such as
mutagenicity/genotoxicity (determinations of whether the chemical
interacts directly with DNA), structure activity, and metabolism.
2. Tier II: Weight of evidence of possible human carcinogenic
effects sufficient to derive a Tier II human cancer value shall include
those possible human carcinogens for which there are at a minimum, data
sufficient for quantitative risk assessment, but for which data are
inadequate for Tier I criterion development due to a tumor response of
marginal statistical significance or inability to derive a strong dose-
response relationship. In determining whether to derive Tier II human
cancer values, additional evidence that shall be considered includes but
is not limited to available information on mode of action such as
mutagenicity/genotoxicity (determinations of whether the chemical
interacts directly with DNA), structure activity and metabolism. As with
the use of data on possible human carcinogens in developing Tier I
criteria, the decision to use data on possible human carcinogens to
derive Tier II values shall be made on a case-by-case basis.
B. Noncarcinogens. All available toxicity data shall be evaluated
considering the full range of possible health effects of a chemical,
i.e., acute/subacute, chronic/subchronic and reproductive/developmental
effects, in order to best describe the dose-response relationship of the
chemical, and to calculate human noncancer criteria and values which
will protect against the most sensitive endpoint(s) of toxicity.
Although it is desirable to have an extensive database which considers a
wide range of possible adverse effects, this type of data exists for a
very limited number of chemicals. For many others, there is a range in
quality and quantity of data available. To assure minimum reliability of
criteria and values, it is necessary to establish a minimum database
with which to develop Tier I criteria or Tier II values. The following
represent the minimum data sets necessary for this procedure.
1. Tier I: The minimum data set sufficient to derive a Tier I human
HNC shall include at least one well-conducted epidemiologic study or
animal study. A well-conducted epidemiologic study for a Tier I HNC must
quantify exposure level(s) and demonstrate positive association between
exposure to a chemical and adverse effect(s) in humans. A
[[Page 516]]
well-conducted study in animals must demonstrate a dose response
relationship involving one or more critical effect(s) biologically
relevant to humans. (For example, study results from an animal whose
pharmacokinetics and toxicokinetics match those of a human would be
considered most biologically relevant.) Ideally, the duration of a study
should span multiple generations of exposed test species or at least a
major portion of the lifespan of one generation. This type of data is
currently very limited. By the use of uncertainty adjustments, shorter
term studies (such as 90-day subchronic studies) with evaluation of more
limited effect(s) may be used to extrapolate to longer exposures or to
account for a variety of adverse effects. For Tier I criteria developed
pursuant to this procedure, such a limited study must be conducted for
at least 90 days in rodents or 10 percent of the lifespan of other
appropriate test species and demonstrate a no observable adverse effect
level (NOAEL). Chronic studies of one year or longer in rodents or 50
percent of the lifespan or greater in other appropriate test species
that demonstrate a lowest observable adverse effect level (LOAEL) may be
sufficient for use in Tier I criterion derivation if the effects
observed at the LOAEL were relatively mild and reversible as compared to
effects at higher doses. This does not preclude the use of a LOAEL from
a study (of chronic duration) with only one or two doses if the effects
observed appear minimal when compared to effect levels observed at
higher doses in other studies.
2. Tier II: When the minimum data for deriving Tier I criteria are
not available to meet the Tier I data requirements, a more limited
database may be considered for deriving Tier II values. As with Tier I
criteria, all available data shall be considered and ideally should
address a range of adverse health effects with exposure over a
substantial portion of the lifespan (or multiple generations) of the
test species. When such data are lacking it may be necessary to rely on
less extensive data in order to establish a Tier II value. With the use
of appropriate uncertainty factors to account for a less extensive
database, the minimum data sufficient to derive a Tier II value shall
include a NOAEL from at least one well-conducted short-term repeated
dose study. This study shall be of at least 28 days duration, in animals
demonstrating a dose-response, and involving effects biologically
relevant to humans. Data from studies of longer duration (greater than
28 days) and LOAELs from such studies (greater than 28 days) may be more
appropriate in some cases for derivation of Tier II values. Use of a
LOAEL should be based on consideration of the following information:
severity of effect, quality of the study and duration of the study.
C. Bioaccumulation factors (BAFs).
1. Tier I for Carcinogens and Noncarcinogens: To be considered a
Tier I cancer or noncancer human health criterion, along with satisfying
the minimum toxicity data requirements of sections II.A.1 and II.B.1 of
this appendix, a chemical must have the following minimum
bioaccumulation data. For all organic chemicals either: (a) a field-
measured BAF; (b) a BAF derived using the BSAF methodology; or (c) a
chemical with a BAF less than 125 regardless of how the BAF was derived.
For all inorganic chemicals, including organometals such as mercury,
either: (a) a field-measured BAF or (b) a laboratory-measured BCF.
2. Tier II for Carcinogens and Noncarcinogens: A chemical is
considered a Tier II cancer or noncancer human health value if it does
not meet either the minimum toxicity data requirements of sections
II.A.1 and II.B.1 of this appendix or the minimum bioaccumulation data
requirements of section II.C.1 of this appendix.
III. Principles for Development of Tier I Criteria or Tier II Values
The fundamental components of the procedure to calculate Tier I
criteria or Tier II values are the same. However, certain of the aspects
of the procedure designed to account for short-duration studies or other
limitations in data are more likely to be relevant in deriving Tier II
values than Tier I criteria.
A. Carcinogens.
1. A non-threshold mechanism of carcinogenesis shall be assumed
unless biological data adequately demonstrate the existence of a
threshold on a chemical-specific basis.
2. All appropriate human epidemiologic data and animal cancer
bioassay data shall be considered. Data specific to an environmentally
appropriate route of exposure shall be used. Oral exposure should be
used preferentially over dermal and inhalation since, in most cases, the
exposure routes of greatest concern are fish consumption and drinking
water/incidental ingestion. The risk associated dose shall be set at a
level corresponding to an incremental cancer risk of one in 100,000. If
acceptable human epidemiologic data are available for a chemical, it
shall be used to derive the risk associated dose. If acceptable human
epidemiologic data are not available, the risk associated dose shall be
derived from available animal bioassay data. Data from a species that is
considered most biologically relevant to humans (i.e., responds most
like humans) is preferred where all other considerations regarding
quality of data are equal. In the absence of data to distinguish the
most relevant species, data from the most sensitive species tested,
i.e., the species showing a carcinogenic effect at the lowest
administered dose, shall generally be used.
[[Page 517]]
3. When animal bioassay data are used and a non-threshold mechanism
of carcinogenicity is assumed, the data are fitted to a linearized
multistage computer model (e.g., Global '86 or equivalent model). Global
'86 is the linearized multistage model, derived by Howe, Crump and Van
Landingham (1986), which EPA uses to determine cancer potencies. The
upper-bound 95 percent confidence limit on risk (or, the lower 95
percent confidence limit on dose) at the one in 100,000 risk level shall
be used to calculate a risk associated dose (RAD). Other models,
including modifications or variations of the linear multistage model
which are more appropriate to the available data may be used where
scientifically justified.
4. If the duration of the study is significantly less than the
natural lifespan of the test animal, the slope may be adjusted on a
case-by-case basis to compensate for latent tumors which were not
expressed (e.g., U.S. EPA, 1980) In the absence of alternative
approaches which compensate for study durations significantly less than
lifetime, the permitting authority may use the process described in the
1980 National Guidelines (see 45 FR 79352).
5. A species scaling factor shall be used to account for differences
between test species and humans. It shall be assumed that milligrams per
surface area per day is an equivalent dose between species (U.S. EPA,
1986). All doses presented in mg/kg bodyweight will be converted to an
equivalent surface area dose by raising the mg/kg dose to the 2/3 power.
However, if adequate pharmacokinetic and metabolism studies are
available, these data may be factored into the adjustment for species
differences on a case-by-case basis.
6. Additional data selection and adjustment decisions must also be
made in the process of quantifying risk. Consideration must be given to
tumor selection for modeling, e.g., pooling estimates for multiple tumor
types and identifying and combining benign and malignant tumors. All
doses shall be adjusted to give an average daily dose over the study
duration. Adjustments in the rate of tumor response must be made for
early mortality in test species. The goodness-of-fit of the model to the
data must also be assessed.
7. When a linear, non-threshold dose response relationship is
assumed, the RAD shall be calculated using the following equation:
[GRAPHIC] [TIFF OMITTED] TR23MR95.114
Where:
RAD=risk associated dose in milligrams of toxicant per kilogram body
weight per day (mg/kg/day).
0.00001 (1x10-5)=incremental risk of developing cancer equal
to one in 100,000.
q1*=slope factor (mg/kg/day)-1.
8. If human epidemiologic data and/or other biological data (animal)
indicate that a chemical causes cancer via a threshold mechanism, the
risk associated dose may, on a case-by-case basis, be calculated using a
method which assumes a threshold mechanism is operative.
B. Noncarcinogens.
1. Noncarcinogens shall generally be assumed to have a threshold
dose or concentration below which no adverse effects should be observed.
Therefore, the Tier I criterion or Tier II value is the maximum water
concentration of a substance at or below which a lifetime exposure from
drinking the water, consuming fish caught in the water, and ingesting
water as a result of participating in water-related recreation
activities is likely to be without appreciable risk of deleterious
effects.
For some noncarcinogens, there may not be a threshold dose below
which no adverse effects should be observed. Chemicals acting as
genotoxic teratogens and germline mutagens are thought to possibly
produce reproductive and/or developmental effects via a genetically
linked mechanism which may have no threshold. Other chemicals also may
not demonstrate a threshold. Criteria for these types of chemicals will
be established on a case-by-case basis using appropriate assumptions
reflecting the likelihood that no threshold exists.
2. All appropriate human and animal toxicologic data shall be
reviewed and evaluated. To the maximum extent possible, data most
specific to the environmentally relevant route of exposure shall be
used. Oral exposure data should be used preferentially over dermal and
inhalation since, in most cases, the exposure routes of greatest concern
are fish consumption and drinking water/incidental ingestion. When
acceptable human data are not available (e.g., well-conducted
epidemiologic studies), animal data from species most biologically
relevant to humans shall be used. In the absence of data to distinguish
the most relevant species, data from the most sensitive animal species
tested, i.e., the species showing a toxic effect at the lowest
administered dose (given a relevant route of exposure), should generally
be used.
3. Minimum data requirements are specified in section II.B of this
appendix. The experimental exposure level representing the highest level
tested at which no adverse effects were demonstrated (NOAEL) from
studies satisfying the provisions of section II.B of this appendix shall
be used for criteria calculations. In the absence of a NOAEL, the LOAEL
from studies satisfying the provisions of section II.B of this appendix
may be
[[Page 518]]
used if it is based on relatively mild and reversible effects.
4. Uncertainty factors shall be used to account for the
uncertainties in predicting acceptable dose levels for the general human
population based upon experimental animal data or limited human data.
a. An uncertainty factor of 10 shall generally be used when
extrapolating from valid experimental results from studies on prolonged
exposure to average healthy humans. This 10-fold factor is used to
protect sensitive members of the human population.
b. An uncertainty factor of 100 shall generally be used when
extrapolating from valid results of long-term studies on experimental
animals when results of studies of human exposure are not available or
are inadequate. In comparison to a, above, this represents an additional
10-fold uncertainty factor in extrapolating data from the average animal
to the average human.
c. An uncertainty factor of up to 1000 shall generally be used when
extrapolating from animal studies for which the exposure duration is
less than chronic, but greater than subchronic (e.g., 90 days or more in
length), or when other significant deficiencies in study quality are
present, and when useful long-term human data are not available. In
comparison to b, above, this represents an additional UF of up to 10-
fold for less than chronic, but greater than subchronic, studies.
d. An UF of up to 3000 shall generally be used when extrapolating
from animal studies for which the exposure duration is less than
subchronic (e.g., 28 days). In comparison to b above, this represents an
additional UF of up to 30-fold for less than subchronic studies (e.g.,
28-day). The level of additional uncertainty applied for less than
chronic exposures depends on the duration of the study used relative to
the lifetime of the experimental animal.
e. An additional UF of between one and ten may be used when deriving
a criterion from a LOAEL. This UF accounts for the lack of an
identifiable NOAEL. The level of additional uncertainty applied may
depend upon the severity and the incidence of the observed adverse
effect.
f. An additional UF of between one and ten may be applied when there
are limited effects data or incomplete sub-acute or chronic toxicity
data (e.g., reproductive/developmental data). The level of quality and
quantity of the experimental data available as well as structure-
activity relationships may be used to determine the factor selected.
g. When deriving an UF in developing a Tier I criterion or Tier II
value, the total uncertainty, as calculated following the guidance of
sections 4.a through f, cited above, shall not exceed 10,000 for Tier I
criteria and 30,000 for Tier II values.
5. All study results shall be converted, as necessary, to the
standard unit for acceptable daily exposure of milligrams of toxicant
per kilogram of body weight per day (mg/kg/day). Doses shall be adjusted
for continuous exposure (i.e., seven days/week, 24 hours/day, etc.).
C. Criteria and Value Derivation.
1. Standard Exposure Assumptions. The following represent the
standard exposure assumptions used to calculate Tier I criteria and Tier
II values for carcinogens and noncarcinogens. Higher levels of exposure
may be assumed by States and Tribes pursuant to Clean Water Act (CWA)
section 510, or where appropriate in deriving site-specific criteria
pursuant to procedure 1 in appendix F to part 132.
BW = body weight of an average human (BW = 70kg).
WCd = per capita water consumption (both drinking and
incidental exposure) for surface waters classified as public water
supplies = two liters/day.
--or--
WCr = per capita incidental daily water ingestion for
surface waters not used as human drinking water sources = 0.01 liters/
day.
FC = per capita daily consumption of regionally caught freshwater
fish = 0.015kg/day (0.0036 kg/day for trophic level 3 and 0.0114 kg/day
for trophic level 4).
BAF = bioaccumulation factor for trophic level 3 and trophic level
4, as derived using the BAF methodology in appendix B to part 132.
2. Carcinogens. The Tier I human cancer criteria or Tier II values
shall be calculated as follows:
[GRAPHIC] [TIFF OMITTED] TR23MR95.115
Where:
HCV=Human Cancer Value in milligrams per liter (mg/L).
RAD=Risk associated dose in milligrams toxicant per kilogram body weight
per day
[[Page 519]]
(mg/kg/day) that is associated with a lifetime incremental cancer risk
equal to one in 100,000.
BW=weight of an average human (BW=70 kg).
WCd=per capita water consumption (both drinking and
incidental exposure) for surface waters classified as public water
supplies=two liters/day.
or
WCr=per capita incidental daily water ingestion for surface
waters not used as human drinking water sources=0.01 liters/day.
FCTL3=mean consumption of trophic level 3 of regionally
caught freshwater fish=0.0036 kg/day.
FCTL4=mean consumption of trophic level 4 of regionally
caught freshwater fish=0.0114 kg/day.
BAF\HH\TL3=bioaccumulation factor for trophic level 3 fish,
as derived using the BAF methodology in appendix B to part 132.
BAF\HH\TL4=bioaccumulation factor for trophic level 4 fish,
as derived using the BAF methodology in appendix B to part 132.
3. Noncarcinogens. The Tier I human noncancer criteria or Tier II
values shall be calculated as follows:
[GRAPHIC] [TIFF OMITTED] TR23MR95.116
Where:
HNV=Human noncancer value in milligrams per liter (mg/L).
ADE=Acceptable daily exposure in milligrams toxicant per kilogram body
weight per day (mg/kg/day).
RSC=Relative source contribution factor of 0.8. An RSC derived from
actual exposure data may be developed using the methodology outlined by
the 1980 National Guidelines (see 45 FR 79354).
BW=weight of an average human (BW=70 kg).
WCd=per capita water consumption (both drinking and
incidental exposure) for surface waters classified as public water
supplies=two liters/day.
or
WCr=per capita incidental daily water ingestion for surface
waters not used as human drinking water sources=0.01 liters/day.
FCTL3=mean consumption of trophic level 3 fish by regional
sport fishers of regionally caught freshwater fish=0.0036 kg/day.
FCTL4=mean consumption of trophic level 4 fish by regional
sport fishers of regionally caught freshwater fish=0.0114 kg/day.
BAF\HH\TL3=human health bioaccumulation factor for edible
portion of trophic level 3 fish, as derived using the BAF methodology in
appendix B to part 132.
BAF\HH\TL4=human health bioaccumulation factor for edible
portion of trophic level 4 fish, as derived using the BAF methodology in
appendix B to part 132.
IV. References
A. Howe, R.B., K.S. Crump and C. Van Landingham. 1986. Computer
Program to Extrapolate Quantitative Animal Toxicity Data to Low Doses.
Prepared for EPA under subcontract 2-251U-2745 to Research
Triangle Institute.
B. U.S. Environmental Protection Agency. 1980. Water Quality
Criteria Availability, Appendix C Guidelines and Methodology Used in the
Preparation of Health Effects Assessment Chapters of the Consent Decree
Water Quality Criteria Documents. Available from U.S. Environmental
Protection Agency, Office of Water Resource Center (WH-550A), 1200
Pennsylvania Ave., NW., Washington, DC 20460.
C. U.S. Environmental Protection Agency. 1986. Guidelines for
Carcinogen Risk Assessment. Available from U.S. Environmental Protection
Agency, Office of Water Resource Center (WH-550A), 1200 Pennsylvania
Ave., NW., Washington, DC 20460.
Appendix D to Part 132--Great Lakes Water Quality Initiative Methodology
for the Development of Wildlife Criteria
Great Lakes States and Tribes shall adopt provisions consistent with
(as protective as) this appendix.
I. Introduction
A. A Great Lakes Water Quality Wildlife Criterion (GLWC) is the
concentration of a substance which is likely to, if not exceeded,
protect avian and mammalian wildlife populations inhabiting the Great
Lakes basin from adverse effects resulting from the ingestion of water
and aquatic prey taken from surface waters of the Great Lakes System.
These criteria are based on existing toxicological studies of the
substance of concern and quantitative information about the exposure of
wildlife species to the substance (i.e., food and water consumption
rates). Since toxicological and exposure data for individual wildlife
species are limited, a GLWC
[[Page 520]]
is derived using a methodology similar to that used to derive noncancer
human health criteria (Barnes and Dourson, 1988; NAS, 1977; NAS, 1980;
U.S. EPA, 1980). Separate avian and mammalian values are developed using
taxonomic class-specific toxicity data and exposure data for five
representative Great Lakes basin wildlife species. The wildlife species
selected are representative of avian and mammalian species resident in
the Great Lakes basin which are likely to experience the highest
exposures to bioaccumulative contaminants through the aquatic food web;
they are the bald eagle, herring gull, belted kingfisher, mink, and
river otter.
B. This appendix establishes a methodology which is required when
developing Tier I wildlife criteria for bioaccumulative chemicals of
concern (BCCs). The use of the equation provided in the methodology is
encouraged, but not required, for the development of Tier I criteria or
Tier II values for pollutants other than those identified in Table 6-A
for which Tier I criteria or Tier II values are determined to be
necessary for the protection of wildlife in the Great Lakes basin. A
discussion of the methodology for deriving Tier II values can be found
in the Great Lakes Water Quality Initiative Technical Support Document
for Wildlife Criteria (Wildlife TSD).
C. In the event that this methodology is used to develop criteria
for pollutants other than BCCs, or in the event that the Tier II
methodology described in the Wildlife TSD is used to derive Tier II
values, the methodology for deriving bioaccumulation factors under
appendix B to part 132 must be used in either derivation. For chemicals
which do not biomagnify to the extent of BCCs, it may be appropriate to
select different representative species which are better examples of
species with the highest exposures for the given chemical. The equation
presented in this methodology, however, is still encouraged. In
addition, procedure 1 of appendix F of this part describes the
procedures for calculating site-specific wildlife criteria.
D. The term ``wildlife value'' (WV) is used to denote the value for
each representative species which results from using the equation
presented below, the value obtained from averaging species values within
a class, or any value derived from application of the site-specific
procedure provided in procedure 1 of appendix F of this part. The WVs
calculated for the representative species are used to calculate
taxonomic class-specific WVs. The WV is the concentration of a substance
which, if not exceeded, should better protect the taxon in question.
E. ``Tier I wildlife criterion,'' or ``Tier I criterion'' is used to
denote the number derived from data meeting the Tier I minimum database
requirements, and which will be protective of the two classes of
wildlife. It is synonymous with the term ``GLWC,'' and the two are used
interchangeably.
II. Calculation of Wildlife Values for Tier I Criteria
Table 4 of Part 132 and Table D-1 of this appendix contain criteria
calculated by EPA using the methodology provided below.
A. Equation for Avian and Mammalian Wildlife Values. Tier I wildlife
values for the pollutants designated BCCs pursuant to part 132 are to be
calculated using the equation presented below.
[GRAPHIC] [TIFF OMITTED] TR23MR95.117
Where:
WV=Wildlife Value in milligrams of substance per liter (mg/L).
TD=Test Dose (TD) in milligrams of substance per kilograms per day (mg/
kg-d) for the test species. This shall be either a NOAEL or a LOAEL.
UFA=Uncertainty Factor (UF) for extrapolating toxicity data
across species (unitless). A species-specific UF shall be selected and
applied to each representative species, consistent with the equation.
UFS=UF for extrapolating from subchronic to chronic exposures
(unitless).
UFL=UF for LOAEL to NOAEL extrapolations (unitless).
Wt=Average weight in kilograms (kg) for the representative species.
W=Average daily volume of water consumed in liters per day (L/d) by the
representative species.
FTLi=Average daily amount of food consumed from trophic level
i in kilograms per day (kg/d) by the representative species.
BAF\WL\TLi=Bioaccumulation factor (BAF) for wildlife food in
trophic level i in liters per kilogram (L/kg), developed using the BAF
methodology in appendix B to part 132, Methodology for Development of
Bioaccumulation Factors. For consumption of piscivorous birds by other
birds (e.g., herring gull by eagles), the BAF is derived by multiplying
the trophic level 3 BAF for fish by a biomagnification factor to account
for the biomagnification from fish to the consumed birds.
B. Identification of Representative Species for Protection. For
bioaccumulative chemicals, piscivorous species are identified as the
focus of concern for wildlife criteria development in the Great Lakes.
An analysis of known or estimated exposure components for avian and
mammalian wildlife species is presented in the Wildlife TSD. This
analysis identifies three avian species (eagle, kingfisher and herring
gull) and two mammalian
[[Page 521]]
species (mink and otter) as representative species for protection. The
TD obtained from toxicity data for each taxonomic class is used to
calculate WVs for each of the five representative species.
C. Calculation of Avian and Mammalian Wildlife Values and GLWC
Derivation. The avian WV is the geometric mean of the WVs calculated for
the three representative avian species. The mammalian WV is the
geometric mean of the WVs calculated for the two representative
mammalian species. The lower of the mammalian and avian WVs must be
selected as the GLWC.
III. Parameters of the Effect Component of the Wildlife Criteria
Methodology
A. Definitions. The following definitions provide additional
specificity and guidance in the evaluation of toxicity data and the
application of this methodology.
Acceptable endpoints. For the purpose of wildlife criteria
derivation, acceptable subchronic and chronic endpoints are those which
affect reproductive or developmental success, organismal viability or
growth, or any other endpoint which is, or is directly related to,
parameters that influence population dynamics.
Chronic effect. An adverse effect that is measured by assessing an
acceptable endpoint, and results from continual exposure over several
generations, or at least over a significant part of the test species'
projected life span or life stage.
Lowest-observed-adverse-effect-level (LOAEL). The lowest tested dose
or concentration of a substance which resulted in an observed adverse
effect in exposed test organisms when all higher doses or concentrations
resulted in the same or more severe effects.
No-observed-adverse-effect-level (NOAEL). The highest tested dose or
concentration of a substance which resulted in no observed adverse
effect in exposed test organisms where higher doses or concentrations
resulted in an adverse effect.
Subchronic effect. An adverse effect, measured by assessing an
acceptable endpoint, resulting from continual exposure for a period of
time less than that deemed necessary for a chronic test.
B. Minimum Toxicity Database for Tier I Criteria Development. A TD
value is required for criterion calculation. To derive a Tier I
criterion for wildlife, the data set shall provide enough data to
generate a subchronic or chronic dose-response curve for any given
substance for both mammalian and avian species. In reviewing the
toxicity data available which meet the minimum data requirements for
each taxonomic class, the following order of preference shall be applied
to select the appropriate TD to be used for calculation of individual
WVs. Data from peer-reviewed field studies of wildlife species take
precedence over other types of studies, where such studies are of
adequate quality. An acceptable field study must be of subchronic or
chronic duration, provide a defensible, chemical-specific dose-response
curve in which cause and effect are clearly established, and assess
acceptable endpoints as defined in this document. When acceptable
wildlife field studies are not available, or determined to be of
inadequate quality, the needed toxicity information may come from peer-
reviewed laboratory studies. When laboratory studies are used,
preference shall be given to laboratory studies with wildlife species
over traditional laboratory animals to reduce uncertainties in making
interspecies extrapolations. All available laboratory data and field
studies shall be reviewed to corroborate the final GLWC, to assess the
reasonableness of the toxicity value used, and to assess the
appropriateness of any UFs which are applied. When evaluating the
studies from which a test dose is derived in general, the following
requirements must be met:
1. The mammalian data must come from at least one well-conducted
study of 90 days or greater designed to observe subchronic or chronic
effects as defined in this document.
2. The avian data must come from at least one well-conducted study
of 70 days or greater designed to observe subchronic or chronic effects
as defined in this document.
3. In reviewing the studies from which a TD is derived for use in
calculating a WV, studies involving exposure routes other than oral may
be considered only when an equivalent oral daily dose can be estimated
and technically justified because the criteria calculations are based on
an oral route of exposure.
4. In assessing the studies which meet the minimum data
requirements, preference should be given to studies which assess effects
on developmental or reproductive endpoints because, in general, these
are more important endpoints in ensuring that a population's
productivity is maintained. The Wildlife TSD provides additional
discussion on the selection of an appropriate toxicity study.
C. Selection of TD Data. In selecting data to be used in the
derivation of WVs, the evaluation of acceptable endpoints, as defined in
Section III.A of this appendix, will be the primary selection criterion.
All data not part of the selected subset may be used to assess the
reasonableness of the toxicity value and the appropriateness of the Ufs
which are applied.
1. If more than one TD value is available within a taxonomic class,
based on different endpoints of toxicity, that TD, which is likely to
reflect best potential impacts to wildlife populations through resultant
changes in mortality or fecundity rates, shall be used for the
calculation of WVs.
[[Page 522]]
2. If more than one TD is available within a taxonomic class, based
on the same endpoint of toxicity, the TD from the most sensitive species
shall be used.
3. If more than one TD based on the same endpoint of toxicity is
available for a given species, the TD for that species shall be
calculated using the geometric mean of those TDs.
D. Exposure Assumptions in the Determination of the TD. 1. In those
cases in which a TD is available in units other than milligrams of
substance per kilograms per day (mg/kg/d), the following procedures
shall be used to convert the TD to the appropriate units prior to
calculating a WV.
2. If the TD is given in milligrams of toxicant per liter of water
consumed by the test animals (mg/L), the TD shall be multiplied by the
daily average volume of water consumed by the test animals in liters per
day (L/d) and divided by the average weight of the test animals in
kilograms (kg).
3. If the TD is given in milligrams of toxicant per kilogram of food
consumed by the test animals (mg/kg), the TD shall be multiplied by the
average amount of food in kilograms consumed daily by the test animals
(kg/d) and divided by the average weight of the test animals in
kilograms (kg).
E. Drinking and Feeding Rates. 1. When drinking and feeding rates
and body weight are needed to express the TD in milligrams of substance
per kilograms per day (mg/kg/d), they are obtained from the study from
which the TD was derived. If not already determined, body weight, and
drinking and feeding rates are to be converted to a wet weight basis.
2. If the study does not provide the needed values, the values shall
be determined from appropriate scientific literature. For studies done
with domestic laboratory animals, either the Registry of Toxic Effects
of Chemical Substances (National Institute for Occupational Safety and
Health, the latest edition, Cincinnati, OH), or Recommendations for and
Documentation of Biological Values for Use in Risk Assessment (U.S. EPA,
1988) should be consulted. When these references do not contain exposure
information for the species used in a given study, either the allometric
equations from Calder and Braun (1983) and Nagy (1987), which are
presented below, or the exposure estimation methods presented in Chapter
4 of the Wildlife Exposure Factors Handbook (U.S. EPA, 1993), should be
applied to approximate the needed feeding or drinking rates. Additional
discussion and recommendations are provided in the Wildlife TSD. The
choice of the methods described above is at the discretion of the State
or Tribe.
3. For mammalian species, the general allometric equations are:
a. F = 0.0687 x (Wt)\0.82\
Where:
F = Feeding rate of mammalian species in kilograms per day (kg/d) dry
weight.
Wt = Average weight in kilograms (kg) of the test animals.
b. W = 0.099 x (Wt)\0.90\
Where:
W = Drinking rate of mammalian species in liters per day (L/d).
Wt = Average weight in kilograms (kg) of the test animals.
4. For avian species, the general allometric equations are:
a. F = 0.0582 (Wt)\0.65\
Where:
F = Feeding rate of avian species in kilograms per day (kg/d) dry
weight.
Wt = Average weight in kilograms (kg) of the test animals.
b. W = 0.059 x (Wt)\0.67\
Where:
W = Drinking rate of avian species in liters per day (L/d).
Wt = Average weight in kilograms (kg) of the test animals.
F. LOAEL to NOAEL Extrapolations (UFL). In those cases in
which a NOAEL is unavailable as the TD and a LOAEL is available, the
LOAEL may be used to estimate the NOAEL. If used, the LOAEL shall be
divided by an UF to estimate a NOAEL for use in deriving WVs. The value
of the UF shall not be less than one and should not exceed 10, depending
on the dose-response curve and any other available data, and is
represented by UFL in the equation expressed in Section II.A
of this appendix. Guidance for selecting an appropriate UFL,
based on a review of available wildlife toxicity data, is available in
the Wildlife TSD.
G. Subchronic to Chronic Extrapolations (USS). In
instances where only subchronic data are available, the TD may be
derived from subchronic data. In such cases, the TD shall be divided by
an UF to extrapolate from subchronic to chronic levels. The value of the
UF shall not be less than one and should not exceed 10, and is
represented by UFS in the equation expressed in Section II.A
of this appendix. This factor is to be used when assessing highly
bioaccumulative substances where toxicokinetic considerations suggest
that a bioassay of limited length underestimates chronic effects.
Guidance for selecting an appropriate UFS, based on a review
of available wildlife toxicity data, is available in the Wildlife TSD.
H. Interspecies Extrapolations (UFA). 1. The selection of
the UFA shall be based on the available toxicological data
and on available data concerning the physicochemical, toxicokinetic, and
toxicodynamic properties of the substance in question and the amount and
quality of available data. This value is
[[Page 523]]
an UF that is intended to account for differences in toxicological
sensitivity among species. Guidance for selecting an appropriate
UFA, based on a review of available wildlife toxicity data,
is available in the Wildlife TSD. Additional discussion of an
interspecies UF located in appendix A to the Great Lakes Water Quality
Initiative Technical Support Document for Human Health Criteria may be
useful in determining the appropriate value for UFA.
2. For the derivation of Tier I criteria, a UFA shall not
be less than one and should not exceed 100, and shall be applied to each
of the five representative species, based on existing data and best
professional judgment. The value of UFA may differ for each
of the representative species.
3. For Tier I wildlife criteria, the UFA shall be used
only for extrapolating toxicity data across species within a taxonomic
class, except as provided below. The Tier I UFA is not
intended for interclass extrapolations because of the poorly defined
comparative toxicokinetic and toxicodynamic parameters between mammals
and birds. However, an interclass extrapolation employing a
UFA may be used for a given chemical if it can be supported
by a validated biologically-based dose-response model or by an analysis
of interclass toxicological data, considering acceptable endpoints, for
a chemical analog that acts under the same mode of toxic action.
IV. Parameters of the Exposure Component of the Wildlife Criteria
Methodology
A. Drinking and Feeding Rates of Representative Species. The body
weights (Wt), feeding rates (FTli), drinking rates (W), and
trophic level dietary composition (as food ingestion rate and percent in
diet) for each of the five representative species are presented in Table
D-2 of this appendix. Guidance on incorporating the non-aquatic portion
of the bald eagle and mink diets in the criteria calculations is
available in the Wildlife TSD.
B. BAFs. The Methodology for Development of Bioaccumulation Factors
is presented in appendix B to part 132. Trophic level 3 and 4 BAFs are
used to derive Wvs because these are the trophic levels at which the
representative species feed.
V. References
A. Barnes, D.G. and M. Dourson. 1988. Reference Dose (RfD):
Description and Use in Health Risk Assessments. Regul. Toxicol.
Pharmacol. 8:471-486.
B. Calder III, W.A. and E.J. Braun. 1983. Scaling of Osmotic
Regulation in Mammals and Birds. American Journal of Physiology.
244:601-606.
C. Nagy, K.A. 1987. Field Metabolic Rate and Food Requirement
Scaling in Mammals and Birds. Ecological Monographs. 57(2):111-128.
D. National Academy of Sciences. 1977. Chemical Contaminants: Safety
and Risk Assessment, in Drinking Water and Health, Volume 1. National
Academy Press.
E. National Academy of Sciences. 1980. Problems of Risk Estimation,
in Drinking Water and Health, Volume 3. National Academy Press.
F. National Institute for Occupational Safety and Health. Latest
edition. Registry of Toxic Effects of Chemical Substances. Division of
Standards Development and Technology Transfer. (Available only on
microfiche or as an electronic database.)
G. U.S. EPA. 1980. Appendix C. Guidelines and Methodology Used in
the Preparation of Health Effect Assessment Chapters of the Consent
Decree Water Criteria Documents, pp. 79347-79357 in Water Quality
Criteria Documents; Availability. Available from U.S. Environmental
Protection Agency, Office of Water Resource Center (WH-550A), 1200
Pennsylvania Ave., NW, Washington, DC 20460.
H. U.S. EPA. 1988. Recommendations for, and documentation of,
biological values for use in risk assessment. NTIS-PB88-179874.
I. U.S. EPA. 1993. Wildlife Exposure Factors Handbook, Volumes I and
II. EPA/600/R-93/187a and b.
Tables to Appendix D to Part 132
Table D-1--Tier I Great Lakes Wildlife Criteria
------------------------------------------------------------------------
Substance Criterion ([micro]g/L)
------------------------------------------------------------------------
DDT & Metabolites........................... 1.1E-5
Mercury..................................... 1.3E-3
PCBs (total)................................ 7.4E-5
2,3,7,8-TCDD................................ 3.1E-9
------------------------------------------------------------------------
Table D-2--Exposure Parameters for the Five Representative Species Identified for Protection
----------------------------------------------------------------------------------------------------------------
Water
Adult body ingestion Food ingestion rate of Trophic level of prey
Species (units) weight rate (L/ prey in each trophic (percent of diet)
(kg) day) level (kg/day)
----------------------------------------------------------------------------------------------------------------
Mink................................. 0.80 0.081 TL3: 0.159; Other: TL3: 90; Other: 10.
0.0177.
Otter................................ 7.4 0.600 TL3: 0.977; TL4: 0.244. TL3: 80; TL4: 20.
Kingfisher........................... 0.15 0.017 TL3: 0.0672............ TL3: 100.
Herring gull......................... 1.1 0.063 TL3: 0.192; TL4: 0.0480 Fish: 90--TL3: 80; TL4:
20.
[[Page 524]]
.......... ........... Other: 0.0267.......... Other: 10.
Bald eagle........................... 4.6 0.160 TL3: 0.371; TL4: 0.0929 Fish: 92--TL3: 80; TL4:
20.
.......... ........... PB: 00283; Other: Birds: 8--PB: 70; non-
0.0121. aquatic: 30.
----------------------------------------------------------------------------------------------------------------
Note: TL3=trophic level three fish; TL4=trophic level four fish; PB=piscivorous birds; Other=non-aquatic birds
and mammals.
Appendix E to Part 132--Great Lakes Water Quality Initiative
Antidegradation Policy
Great Lakes States and Tribes shall adopt provisions consistent with
(as protective as) appendix E to part 132.
The State or Tribe shall adopt an antidegradation standard
applicable to all waters of the Great Lakes System and identify the
methods for implementing such a standard. Consistent with 40 CFR 131.12,
an acceptable antidegradation standard and implementation procedure are
required elements of a State's or Tribe's water quality standards
program. Consistent with 40 CFR 131.6, a complete water quality
standards submission needs to include both an antidegradation standard
and antidegradation implementation procedures. At a minimum, States and
Tribes shall adopt provisions in their antidegradation standard and
implementation methods consistent with sections I, II, III and IV of
this appendix, applicable to pollutants identified as bioaccumulative
chemicals of concern (BCCs).
I. Antidegradation Standard
This antidegradation standard shall be applicable to any action or
activity by any source, point or nonpoint, of pollutants that is
anticipated to result in an increased loading of BCCs to surface waters
of the Great Lakes System and for which independent regulatory authority
exists requiring compliance with water quality standards. Pursuant to
this standard:
A. Existing instream water uses, as defined pursuant to 40 CFR 131,
and the level of water quality necessary to protect existing uses shall
be maintained and protected. Where designated uses of the waterbody are
impaired, there shall be no lowering of the water quality with respect
to the pollutant or pollutants which are causing the impairment;
B. Where, for any parameter, the quality of the waters exceed levels
necessary to support the propagation of fish, shellfish, and wildlife
and recreation in and on the waters, that water shall be considered high
quality for that parameter consistent with the definition of high
quality water found at section II.A of this appendix and that quality
shall be maintained and protected unless the State or Tribe finds, after
full satisfaction of intergovernmental coordination and public
participation provisions of the State's or Tribe'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
are located. In allowing such degradation, the State or Tribe shall
assure water quality adequate to protect existing uses fully. Further,
the State or Tribe 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. The State or Tribe shall utilize the
Antidegradation Implementation Procedures adopted pursuant to the
requirements of this regulation in determining if any lowering of water
quality will be allowed;
C. Where high quality waters constitute an outstanding national
resource, such as waters of national and State parks and wildlife
refuges and waters of exceptional recreational or ecological
significance, that water quality shall be maintained and protected; and
D. In those cases where the potential lowering of water quality is
associated with a thermal discharge, the decision to allow such
degradation shall be consistent with section 316 of the Clean Water Act
(CWA).
II. Antidegradation Implementation Procedures
A. Definitions.
Control Document. Any authorization issued by a State, Tribal or
Federal agency to any source of pollutants to waters under its
jurisdiction that specifies conditions under which the source is allowed
to operate.
High quality waters. High quality waters are water bodies in which,
on a parameter by parameter basis, the quality of the waters exceeds
levels necessary to support propagation of fish, shellfish, and wildlife
and recreation in and on the water.
[[Page 525]]
Lake Superior Basin--Outstanding International Resource Waters.
Those waters designated as such by a Tribe or State consistent with the
September 1991 Bi-National Program to Restore and Protect the Lake
Superior Basin. The purpose of such designations shall be to ensure that
any new or increased discharges of Lake Superior bioaccumulative
substances of immediate concern are subject to best technology in
process and treatment requirements.
Lake Superior Basin--Outstanding National Resource Waters. Those
waters designated as such by a Tribe or State consistent with the
September 1991 Bi-National Program to Restore and Protect the Lake
Superior Basin. The purpose of such designations shall be to prohibit
new or increased discharges of Lake Superior bioaccumulative substances
of immediate concern from point sources in these areas.
Lake Superior bioaccumulative substances of immediate concern. A
list of substances identified in the September 1991 Bi-National Program
to Restore and Protect the Lake Superior Basin. They include: 2, 3, 7,
8-TCDD; octachlorostyrene; hexachlorobenzene; chlordane; DDT, DDE, and
other metabolites; toxaphene; PCBs; and mercury. Other chemicals may be
added to the list following States' or Tribes' assessments of
environmental effects and impacts and after public review and comment.
Outstanding National Resource Waters. Those waters designated as
such by a Tribe or State. The State or Tribal designation shall describe
the quality of such waters to serve as the benchmark of the water
quality that shall be maintained and protected. Waters that may be
considered for designation as Outstanding National Resource Waters
include, but are not limited to, water bodies that are recognized as:
Important because of protection through official action, such as
Federal or State law, Presidential or secretarial action, international
treaty, or interstate compact;
Having exceptional recreational significance;
Having exceptional ecological significance;
Having other special environmental, recreational, or ecological
attributes; or waters whose designation as Outstanding National Resource
Waters is reasonably necessary for the protection of other waters so
designated.
Significant Lowering of Water Quality. A significant lowering of
water quality occurs when there is a new or increased loading of any BCC
from any regulated existing or new facility, either point source or
nonpoint source for which there is a control document or reviewable
action, as a result of any activity including, but not limited to:
(1) Construction of a new regulated facility or modification of an
existing regulated facility such that a new or modified control document
is required;
(2) Modification of an existing regulated facility operating under a
current control document such that the production capacity of the
facility is increased;
(3) Addition of a new source of untreated or pretreated effluent
containing or expected to contain any BCC to an existing wastewater
treatment works, whether public or private;
(4) A request for an increased limit in an applicable control
document;
(5) Other deliberate activities that, based on the information
available, could be reasonably expected to result in an increased
loading of any BCC to any waters of the Great Lakes System.
b. Notwithstanding the above, changes in loadings of any BCC within
the existing capacity and processes, and that are covered by the
existing applicable control document, are not subject to an
antidegradation review. These changes include, but are not limited to:
(1) Normal operational variability;
(2) Changes in intake water pollutants;
(3) Increasing the production hours of the facility, (e.g., adding a
second shift); or
(4) Increasing the rate of production.
C. Also, excluded from an antidegradation review are new effluent
limits based on improved monitoring data or new water quality criteria
or values that are not a result of changes in pollutant loading.
B. For all waters, the Director shall ensure that the level of water
quality necessary to protect existing uses is maintained. In order to
achieve this requirement, and consistent with 40 CFR 131.10, water
quality standards use designations must include all existing uses.
Controls shall be established as necessary on point and nonpoint sources
of pollutants to ensure that the criteria applicable to the designated
use are achieved in the water and that any designated use of a
downstream water is protected. Where water quality does not support the
designated uses of a waterbody or ambient pollutant concentrations
exceed water quality criteria applicable to that waterbody, the Director
shall not allow a lowering of water quality for the pollutant or
pollutants preventing the attainment of such uses or exceeding such
criteria.
C. For Outstanding National Resource Waters:
1. The Director shall ensure, through the application of appropriate
controls on pollutant sources, that water quality is maintained and
protected.
2. Exception. A short-term, temporary (i.e., weeks or months)
lowering of water quality may be permitted by the Director.
D. For high quality waters, the Director shall ensure that no action
resulting in a lowering of water quality occurs unless an
antidegradation demonstration has been completed pursuant to section III
of this appendix and the information thus provided is
[[Page 526]]
determined by the Director pursuant to section IV of this appendix to
adequately support the lowering of water quality.
1. The Director shall establish conditions in the control document
applicable to the regulated facility that prohibit the regulated
facility from undertaking any deliberate action, such that there would
be an increase in the rate of mass loading of any BCC, unless an
antidegradation demonstration is provided to the Director and approved
pursuant to section IV of this appendix prior to commencement of the
action. Imposition of limits due to improved monitoring data or new
water quality criteria or values, or changes in loadings of any BCC
within the existing capacity and processes, and that are covered by the
existing applicable control document, are not subject to an
antidegradation review.
2. For BCCs known or believed to be present in a discharge, from a
point or nonpoint source, a monitoring requirement shall be included in
the control document. The control document shall also include a
provision requiring the source to notify the Director or any increased
loadings. Upon notification, the Director shall require actions as
necessary to reduce or eliminate the increased loading.
3. Fact Sheets prepared pursuant to 40 CFR 124.8 and 124.56 shall
reflect any conditions developed under sections II.D.1 or II.D.2 of this
appendix and included in a permit.
E. Special Provisions for Lake Superior. The following conditions
apply in addition to those specified in section II.B through II.C of
this appendix for waters of Lake Superior so designated.
1. A State or Tribe may designate certain specified areas of the
Lake Superior Basin as Lake Superior Basin--Outstanding National
Resource Waters for the purpose of prohibiting the new or increased
discharge of Lake Superior bioaccumulative substances of immediate
concern from point sources in these areas.
2. States and Tribes may designate all waters of the Lake Superior
Basin as Outstanding International Resource Waters for the purpose of
restricting the increased discharge of Lake Superior bioaccumulative
substances of immediate concern from point sources consistent with the
requirements of sections III.C and IV.B of this appendix.
F. Exemptions. Except as the Director may determine on a case-by-
case basis that the application of these procedures is required to
adequately protect water quality, or as the affected waterbody is an
Outstanding National Resource Water as defined in section II.A of this
appendix, the procedures in this part do not apply to:
1. Short-term, temporary (i.e., weeks or months) lowering of water
quality;
2. Bypasses that are not prohibited at 40 CFR 122.41(m); and
3. Response actions pursuant to the Comprehensive Environmental
Response, Compensation and Liability Act (CERCLA), as amended, or
similar Federal, State or Tribal authorities, undertaken to alleviate a
release into the environment of hazardous substances, pollutants or
contaminants which may pose an imminent and substantial danger to public
health or welfare.
III. Antidegradation Demonstration
Any entity seeking to lower water quality in a high quality water or
create a new or increased discharge of Lake Superior bioaccumulative
substances of immediate concern in a Lake Superior Outstanding
International Resource Water must first, as required by sections II.D or
II.E.2 of this appendix, submit an antidegradation demonstration for
consideration by the Director. States and Tribes should tailor the level
of detail and documentation in antidegradation reviews, to the specific
circumstances encountered. The antidegradation demonstration shall
include the following:
A. Pollution Prevention Alternatives Analysis. Identify any cost-
effective pollution prevention alternatives and techniques that are
available to the entity, that would eliminate or significantly reduce
the extent to which the increased loading results in a lowering of water
quality.
B. Alternative or Enhanced Treatment Analysis. Identify alternative
or enhanced treatment techniques that are available to the entity that
would eliminate the lowering of water quality and their costs relative
to the cost of treatment necessary to achieve applicable effluent
limitations.
C. Lake Superior. If the States or Tribes designate the waters of
Lake Superior as Outstanding International Resource Waters pursuant to
section II.E.2 of this appendix, then any entity proposing a new or
increased discharge of any Lake Superior bioaccumulative substance of
immediate concern to the Lake Superior Basin shall identify the best
technology in process and treatment to eliminate or reduce the extent of
the lowering of water quality. In this case, the requirements in section
III.B of this appendix do not apply.
D. Important Social or Economic Development Analysis. Identify the
social or economic development and the benefits to the area in which the
waters are located that will be foregone if the lowering of water
quality is not allowed.
E. Special Provision for Remedial Actions. Entities proposing
remedial actions pursuant to the CERCLA, as amended, corrective actions
pursuant to the Resource Conservation and Recovery Act, as amended, or
similar actions pursuant to other Federal or State environmental
statutes may submit information to the Director that demonstrates that
the action utilizes the most cost effective
[[Page 527]]
pollution prevention and treatment techniques available, and minimizes
the necessary lowering of water quality, in lieu of the information
required by sections III.B through III.D of this appendix.
IV. Antidegradation Decision
A. Once the Director determines that the information provided by the
entity proposing to increase loadings is administratively complete, the
Director shall use that information to determine whether or not the
lowering of water quality is necessary, and, if it is necessary, whether
or not the lowering of water quality will support important social and
economic development in the area. If the proposed lowering of water
quality is either not necessary, or will not support important social
and economic development, the Director shall deny the request to lower
water quality. If the lowering of water quality is necessary, and will
support important social and economic development, the Director may
allow all or part of the proposed lowering to occur as necessary to
accommodate the important social and economic development. In no event
may the decision reached under this section allow water quality to be
lowered below the minimum level required to fully support existing and
designated uses. The decision of the Director shall be subject to the
public participation requirements of 40 CFR 25.
B. If States designate the waters of Lake Superior as Outstanding
International Resource Waters pursuant to section II.E.2 of this
appendix, any entity requesting to lower water quality in the Lake
Superior Basin as a result of the new or increased discharge of any Lake
Superior bioaccumulative substance of immediate concern shall be
required to install and utilize the best technology in process and
treatment as identified by the Director.
Appendix F to Part 132--Great Lakes Water Quality Initiative
Implementation Procedures
Procedure 1: Site-specific Modifications to Criteria and Values
Great Lakes States and Tribes shall adopt provisions consistent with
(as protective as) this procedure.
A. Requirements for Site-specific Modifications to Criteria and
Values. Criteria and values may be modified on a site-specific basis to
reflect local environmental conditions as restricted by the following
provisions. Any such modifications must be protective of designated uses
and aquatic life, wildlife or human health and be submitted to EPA for
approval. In addition, any site-specific modifications that result in
less stringent criteria must be based on a sound scientific rationale
and shall not be likely to jeopardize the continued existence of
endangered or threatened species listed or proposed under section 4 of
the Endangered Species Act (ESA) or result in the destruction or adverse
modification of such species' critical habitat. More stringent
modifications shall be developed to protect endangered or threatened
species listed or proposed under section 4 of the ESA, where such
modifications are necessary to ensure that water quality is not likely
to jeopardize the continued existence of such species or result in the
destruction or adverse modification of such species' critical habitat.
More stringent modifications may also be developed to protect candidate
(C1) species being considered by the U.S. Fish and Wildlife Service
(FWS) for listing under section 4 of the ESA, where such modifications
are necessary to protect such species.
1. Aquatic Life.
a. Aquatic life criteria or values may be modified on a site-
specific basis to provide an additional level of protection, pursuant to
authority reserved to the States and Tribes under Clean Water Act (CWA)
section 510.
Guidance on developing site-specific criteria in these instances is
provided in Chapter 3 of the U.S. EPA Water Quality Standards Handbook,
Second Edition--Revised (1994).
b. Less stringent site-specific modifications to chronic or acute
aquatic life criteria or values may be developed when:
i. The local water quality characteristics such as Ph, hardness,
temperature, color, etc., alter the biological availability or toxicity
of a pollutant; or
ii. The sensitivity of the aquatic organisms species that ``occur at
the site'' differs from the species actually tested in developing the
criteria. The phrase ``occur at the site'' includes the species, genera,
families, orders, classes, and phyla that: are usually present at the
site; are present at the site only seasonally due to migration; are
present intermittently because they periodically return to or extend
their ranges into the site; were present at the site in the past, are
not currently present at the site due to degraded conditions, and are
expected to return to the site when conditions improve; are present in
nearby bodies of water, are not currently present at the site due to
degraded conditions, and are expected to be present at the site when
conditions improve. The taxa that ``occur at the site'' cannot be
determined merely by sampling downstream and/or upstream of the site at
one point in time. ``Occur at the site'' does not include taxa that were
once present at the site but cannot exist at the site now due to
permanent physical alteration of the habitat at the site resulting, for
example, from dams, etc.
c. Less stringent modifications also may be developed to acute and
chronic aquatic life criteria or values to reflect local physical and
hydrological conditions.
[[Page 528]]
Guidance on developing site-specific criteria is provided in Chapter
3 of the U.S. EPA Water Quality Standards Handbook, Second Edition--
Revised (1994).
d. Any modifications to protect threatened or endangered aquatic
species required by procedure 1.A of this appendix may be accomplished
using either of the two following procedures:
i. If the Species Mean Acute Value (SMAV) for a listed or proposed
species, or for a surrogate of such species, is lower than the
calculated Final Acute Value (FAV), such lower SMAV may be used instead
of the calculated FAV in developing site-specific modified criteria; or,
ii. The site-specific criteria may be calculated using the
recalculation procedure for site-specific modifications described in
Chapter 3 of the U.S. EPA Water Quality Standards Handbook, Second
Edition--Revised (1994).
2. Wildlife.
a. Wildlife water quality criteria may be modified on a site-
specific basis to provide an additional level of protection, pursuant to
authority reserved to the States and Tribes under CWA section 510.
b. Less stringent site-specific modifications to wildlife water
quality criteria may be developed when a site-specific bioaccumulation
factor (BAF) is derived which is lower than the system-wide BAF derived
under appendix B of this part. The modification must consider both the
mobility of prey organisms and wildlife populations in defining the site
for which criteria are developed. In addition, there must be a showing
that:
i. Any increased uptake of the toxicant by prey species utilizing
the site will not cause adverse effects in wildlife populations; and
ii. Wildlife populations utilizing the site or downstream waters
will continue to be fully protected.
c. Any modification to protect endangered or threatened wildlife
species required by procedure 1.A of this appendix must consider both
the mobility of prey organisms and wildlife populations in defining the
site for which criteria are developed, and may be accomplished by using
the following recommended method.
i. The methodology presented in appendix D to part 132 is used,
substituting appropriate species-specific toxicological,
epidemiological, or exposure information, including changes to the BAF;
ii. An interspecies uncertainty factor of 1 should be used where
epidemiological data are available for the species in question. If
necessary, species-specific exposure parameters can be derived as
presented in Appendix D of this part;
iii. An intraspecies uncertainty factor (to account for protection
of individuals within a wildlife population) should be applied in the
denominator of the effect part of the wildlife equation in appendix D of
this part in a manner consistent with the other uncertainty factors
described in appendix D of this part; and
iv. The resulting wildlife value for the species in question should
be compared to the two class-specific wildlife values which were
previously calculated, and the lowest of the three shall be selected as
the site-specific modification.
Note: Further discussion on the use of this methodology may be found
in the Great Lakes Water Quality Initiative Technical Support Document
for Wildlife Criteria.
3. BAFs.
a. BAFs may be modified on a site-specific basis to larger values,
pursuant to the authority reserved to the States and Tribes under CWA
section 510, where reliable data show that local bioaccumulation is
greater than the system-wide value.
b. BAFs may be modified on a site-specific basis to lower values,
where scientifically defensible, if:
i. The fraction of the total chemical that is freely dissolved in
the ambient water is different than that used to derive the system-wide
BAFs (i.e., the concentrations of particulate organic carbon and the
dissolved organic carbon are different than those used to derive the
system-wide BAFs);
ii. Input parameters of the Gobas model, such as the structure of
the aquatic food web and the disequilibrium constant, are different at
the site than those used to derive the system-wide BAFs;
iii. The percent lipid of aquatic organisms that are consumed and
occur at the site is different than that used to derive the system-wide
BAFs; or
iv. Site-specific field-measured BAFs or biota-sediment accumulation
factor (BSAFs) are determined.
If site-specific BAFs are derived, they shall be derived using the
methodology in appendix B of this part.
c. Any more stringent modifications to protect threatened or
endangered species required by procedure 1.A of this appendix shall be
derived using procedures set forth in the methodology in appendix B of
this part.
4. Human Health.
a. Human health criteria or values may be modified on a site-
specific basis to provide an additional level of protection, pursuant to
authority reserved to the States and Tribes under CWA section 510. Human
health criteria or values shall be modified on a site-specific basis to
provide additional protection appropriate for highly exposed
subpopulations.
b. Less stringent site-specific modifications to human health
criteria or values may be developed when:
i. local fish consumption rates are lower than the rate used in
deriving human health
[[Page 529]]
criteria or values under appendix C of this part; and/or
ii. a site-specific BAF is derived which is lower than that used in
deriving human health criteria or values under appendix C of this part.
B. Notification Requirements. When a State proposes a site-specific
modification to a criterion or value as allowed in section 4.A above,
the State should notify the other Great Lakes States of such a proposal
and, for less stringent criteria, supply appropriate justification.
C. References.
U.S. EPA. 1984. Water Quality Standards Handbook--Revised. Chapter 3
and Appendices. U.S. Environmental Protection Agency, Office of Water
Resource Center (RC-4100), 1200 Pennsylvania Ave., NW., Washington, DC
20960.
Procedure 2: Variances from Water Quality Standards for Point Sources
The Great Lakes States or Tribes may adopt water quality standards
(WQS) variance procedures and may grant WQS variances for point sources
pursuant to such procedures. Variance procedures shall be consistent
with (as protective as) the provisions in this procedure.
A. Applicability. A State or Tribe may grant a variance to a WQS
which is the basis of a water quality-based effluent limitation included
in a National Pollutant Discharge Elimination System (NPDES) permit. A
WQS variance applies only to the permittee requesting the variance and
only to the pollutant or pollutants specified in the variance. A
variance does not affect, or require the State or Tribe to modify, the
corresponding water quality standard for the waterbody as a whole.
1. This provision shall not apply to new Great Lakes dischargers or
recommencing dischargers.
2. A variance to a water quality standard shall not be granted that
would likely jeopardize the continued existence of any endangered or
threatened species listed under Section 4 of the Endangered Species Act
(ESA) or result in the destruction or adverse modification of such
species' critical habitat.
3. A WQS variance shall not be granted if standards will be attained
by implementing effluent limits required under sections 301(b) and 306
of the Clean Water Act (CWA) and by the permittee implementing cost-
effective and reasonable best management practices for nonpoint source
control.
B. Maximum Timeframe for Variances. A WQS variance shall not exceed
five years or the term of the NPDES permit, whichever is less. A State
or Tribe shall review, and modify as necessary, WQS variances as part of
each water quality standards review pursuant to section 303(c) of the
CWA.
C. Conditions to Grant a Variance. A variance may be granted if:
1. The permittee demonstrates to the State or Tribe that attaining
the WQS is not feasible because:
a. Naturally occurring pollutant concentrations prevent the
attainment of the WQS;
b. Natural, ephemeral, intermittent or low flow conditions or water
levels prevent the attainment of the WQS, unless these conditions may be
compensated for by the discharge of sufficient volume of effluent to
enable WQS to be met without violating State or Tribal water
conservation requirements;
c. Human-caused conditions or sources of pollution prevent the
attainment of the WQS and cannot be remedied, or would cause more
environmental damage to correct than to leave in place;
d. Dams, diversions or other types of hydrologic modifications
preclude the attainment of the WQS, and it is not feasible to restore
the waterbody to its original condition or to operate such modification
in a way that would result in the attainment of the WQS;
e. Physical conditions related to the natural features of the
waterbody, such as the lack of a proper substrate cover, flow, depth,
pools, riffles, and the like, unrelated to chemical water quality,
preclude attainment of WQS; or
f. Controls more stringent than those required by sections 301(b)
and 306 of the CWA would result in substantial and widespread economic
and social impact.
2. In addition to the requirements of C.1, above, the permittee
shall also:
a. Show that the variance requested conforms to the requirements of
the State's or Tribe's antidegradation procedures; and
b. Characterize the extent of any increased risk to human health and
the environment associated with granting the variance compared with
compliance with WQS absent the variance, such that the State or Tribe is
able to conclude that any such increased risk is consistent with the
protection of the public health, safety and welfare.
D. Submittal of Variance Application. The permittee shall submit an
application for a variance to the regulatory authority issuing the
permit. The application shall include:
1. All relevant information demonstrating that attaining the WQS is
not feasible based on one or more of the conditions in section C.1 of
this procedure; and,
2. All relevant information demonstrating compliance with the
conditions in section C.2 of this procedure.
E. Public Notice of Preliminary Decision. Upon receipt of a complete
application for a variance, and upon making a preliminary decision
regarding the variance, the State or
[[Page 530]]
Tribe shall public notice the request and preliminary decision for
public comment pursuant to the regulatory authority's Administrative
Procedures Act and shall notify the other Great Lakes States and Tribes
of the preliminary decision. This public notice requirement may be
satisfied by including the supporting information for the variance and
the preliminary decision in the public notice of a draft NPDES permit.
F. Final Decision on Variance Request. The State or Tribe shall
issue a final decision on the variance request within 90 days of the
expiration of the public comment period required in section E of this
procedure. If all or part of the variance is approved by the State or
Tribe, the decision shall include all permit conditions needed to
implement those parts of the variance so approved. Such permit
conditions shall, at a minimum, require:
1. Compliance with an initial effluent limitation which, at the time
the variance is granted, represents the level currently achievable by
the permittee, and which is no less stringent than that achieved under
the previous permit;
2. That reasonable progress be made toward attaining the water
quality standards for the waterbody as a whole through appropriate
conditions;
3. When the duration of a variance is shorter than the duration of a
permit, compliance with an effluent limitation sufficient to meet the
underlying water quality standard, upon the expiration of said variance;
and
4. A provision that allows the permitting authority to reopen and
modify the permit based on any State or Tribal triennial water quality
standards revisions to the variance.
The State shall deny a variance request if the permittee fails to
make the demonstrations required under section C of this procedure.
G. Incorporating Variance into Permit. The State or Tribe shall
establish and incorporate into the permittee's NPDES permit all
conditions needed to implement the variance as determined in section F
of this procedure.
H. Renewal of Variance. A variance may be renewed, subject to the
requirements of sections A through G of this procedure. As part of any
renewal application, the permittee shall again demonstrate that
attaining WQS is not feasible based on the requirements of section C of
this procedure. The permittee's application shall also contain
information concerning its compliance with the conditions incorporated
into its permit as part of the original variance pursuant to sections F
and G of this procedure. Renewal of a variance may be denied if the
permittee did not comply with the conditions of the original variance.
I. EPA Approval. All variances and supporting information shall be
submitted by the State or Tribe to the appropriate EPA regional office
and shall include:
1. Relevant permittee applications pursuant to section D of this
procedure;
2. Public comments and records of any public hearings pursuant to
section E of this procedure;
3. The final decision pursuant to section F of this procedure; and,
4. NPDES permits issued pursuant to section G of this procedure.
5. Items required by sections I.1 through I.3. of this procedure
shall be submitted by the State within 30 days of the date of the final
variance decision. The item required by section I.4 of this procedure
shall be submitted in accordance with the State or Tribe Memorandum of
Agreement with the Regional Administrator pursuant to 40 CFR 123.24.
6. EPA shall review the State or Tribe submittal for compliance with
the CWA pursuant to 40 CFR 123.44, and 40 CFR 131.21.
J. State WQS Revisions. All variances shall be appended to the State
or Tribe WQS rules.
Procedure 3: Total Maximum Daily Loads, Wasteload Allocations for Point
Sources, Load Allocations for Nonpoint Sources, Wasteload Allocations in
the Absence of a TMDL, and Preliminary Wasteload Allocations for
Purposes of Determining the Need for Water Quality Based Effluent Limits
The Great Lakes States and Tribes shall adopt provisions consistent
with (as protective as) this procedure 3 for the purpose of developing
Total Maximum Daily Loads (TMDLs), Wasteload Allocations (WLAs) in the
Absence of TMDLs, and Preliminary Wasteload Allocations for Purposes of
Determining the Need for Water Quality Based Effluent Limits (WQBELs),
except as specifically provided.
A. Where a State or Tribe develops an assessment and remediation
plan that the State or Tribe certifies meets the requirements of
sections B through F of this procedure and public participation
requirements applicable to TMDLs, and that has been approved by EPA as
meeting those requirements under 40 CFR 130.6, the assessment and
remediation plan may be used in lieu of a TMDL for purposes of appendix
F to part 132. Assessment and remediation plans under this procedure may
include, but are not limited to, Lakewide Management Plans, Remedial
Action Plans, and State Water Quality Management Plans. Also, any part
of an assessment and remediation plan that also satisfies one or more
requirements under Clean Water Act (CWA) section 303(d) or implementing
regulations may be incorporated by reference into a TMDL as appropriate.
Assessment and remediation plans under this
[[Page 531]]
section should be tailored to the level of detail and magnitude for the
watershed and pollutant being assessed.
B. General Conditions of Application. Except as provided in Sec.
132.4, the following are conditions applicable to establishing TMDLs for
all pollutants and pollutant parameters in the Great Lakes System, with
the exception of whole effluent toxicity, unless otherwise provided in
procedure 6 of appendix F. Where specified, these conditions also apply
to wasteload allocations (WLAs) calculated in the absence of TMDLs and
to preliminary WLAs for purposes of determining the needs for WQBELs
under procedure 5 of appendix F.
1. TMDLs Required. TMDLs shall, at a minimum, be established in
accordance with the listing and priority setting process established in
section 303(d) of the CWA and at 40 CFR 130.7. Where water quality
standards cannot be attained immediately, TMDLs must reflect reasonable
assurances that water quality standards will be attained in a reasonable
period of time. Some TMDLs may be based on attaining water quality
standards over a period of time, with specific controls on individual
sources being implemented in stages. Determining the reasonable period
of time in which water quality standards will be met is a case-specific
determination considering a number of factors including, but not limited
to: receiving water characteristics; persistence, behavior and ubiquity
of pollutants of concern; type of remediation activities necessary;
available regulatory and non-regulatory controls; and individual State
or Tribal requirements for attainment of water quality standards.
2. Attainment of Water Quality Standards. A TMDL must ensure
attainment of applicable water quality standards, including all numeric
and narrative criteria, Tier I criteria, and Tier II values for each
pollutant or pollutants for which a TMDL is established.
3. TMDL Allocations.
a. TMDLs shall include WLAs for point sources and load allocations
(LAs) for nonpoint sources, including natural background, such that the
sum of these allocations is not greater than the loading capacity of the
water for the pollutant(s) addressed by the TMDL, minus the sum of a
specified margin of safety (MOS) and any capacity reserved for future
growth.
b. Nonpoint source LAs shall be based on:
i. Existing pollutant loadings if changes in loadings are not
reasonably anticipated to occur;
ii. Increases in pollutant loadings that are reasonably anticipated
to occur;
iii. Anticipated decreases in pollutant loadings if such decreased
loadings are technically feasible and are reasonably anticipated to
occur within a reasonable time period as a result of implementation of
best management practices or other load reduction measures. In
determining whether anticipated decreases in pollutant loadings are
technically feasible and can reasonably be expected to occur within a
reasonable period of time, technical and institutional factors shall be
considered. These decisions are case-specific and should reflect the
particular TMDL under consideration.
c. WLAs. The portion of the loading capacity not assigned to
nonpoint sources including background, or to an MOS, or reserved for
future growth is allocated to point sources. Upon reissuance, NPDES
permits for these point sources must include effluent limitations
consistent with WLAs in EPA-approved or EPA-established TMDLs.
d. Monitoring. For LAs established on the basis of subsection b.iii
above, monitoring data shall be collected and analyzed in order to
validate the TMDL's assumptions, to varify anticipated load reductions,
to evaluate the effectiveness of controls being used to implement the
TMDL, and to revise the WLAs and LAs as necessary to ensure that water
quality standards will be achieved within the time-period established in
the TMDL.
4. WLA Values. If separate EPA-approved or EPA-established TMDLs are
prepared for different segments of the same watershed, and the separate
TMDLs each include WLAs for the same pollutant for one or more of the
same point sources, then WQBELs for that pollutant for the point
source(s) shall be consistent with the most stringent of those WLAs in
order to ensure attainment of all applicable water quality standards.
5. Margin of Safety (MOS). Each TMDL shall include a MOS sufficient
to account for technical uncertainties in establishing the TMDL and
shall describe the manner in which the MOS is determined and
incorporated into the TMDL. The MOS may be provided by leaving a portion
of the loading capacity unallocated or by using conservative modeling
assumptions to establish WLAs and LAs. If a portion of the loading
capacity is left unallocated to provide a MOS, the amount left
unallocated shall be described. If conservative modeling assumptions are
relied on to provide a MOS, the specific assumptions providing the MOS
shall be identified.
6. More Stringent Requirements. States and Tribes may exercise
authority reserved to them under section 510 of the CWA to develop more
stringent TMDLs (including WLAs and LAs) than are required herein,
provided that all LAs in such TMDLs reflect actual nonpoint source loads
or those loads that can reasonably be expected to occur within a
reasonable time-period as a result of implementing nonpoint source
controls.
7. Accumulation in Sediments. TMDLs shall reflect, where appropriate
and where sufficient data are available, contributions to the water
column from sediments inside and outside of any applicable mixing zones.
TMDLs
[[Page 532]]
shall be sufficiently stringent so as to prevent accumulation of the
pollutant of concern in sediments to levels injurious to designated or
existing uses, human health, wildlife and aquatic life.
8. Wet Weather Events. Notwithstanding the exception provided for
the establishment of controls on wet weather point sources in Sec.
132.4(e)(1), TMDLs shall reflect, where appropriate and where sufficient
data are available, discharges resulting from wet weather events. This
procedure does not provide specific procedures for considering
discharges resulting from wet weather events. However, some of the
provisions of procedure 3 may be deemed appropriate for considering wet
weather events on a case-by-case basis.
9. Background Concentration of Pollutants. The representative
background concentration of pollutants shall be established in
accordance with this subsection to develop TMDLs, WLAs calculated in the
absence of a TMDL, or preliminary WLAs for purposes of determining the
need for WQBELs under procedure 5 of appendix F. Background loadings may
be accounted for in a TMDL through an allocation to a single
``background'' category or through individual allocations to the various
background sources.
a. Definition of Background. ``Background'' represents all loadings
that: (1) flow from upstream waters into the specified watershed,
waterbody or waterbody segment for which a TMDL, WLA in the absence of a
TMDL or preliminary WLA for the purpose of determining the need for a
WQBEL is being developed; (2) enter the specified watershed, waterbody
or waterbody segment through atmospheric deposition or sediment release
or resuspension; or (3) occur within the watershed, waterbody or
waterbody segment as a result of chemical reactions.
b. Data considerations. When determining what available data are
acceptable for use in calculating background, the State or Tribe should
use best professional judgment, including consideration of the sampling
location and the reliability of the data through comparison to reported
analytical detection levels and quantification levels. When data in more
than one of the data sets or categories described in section B.9.c.i
through B.9.c.iii below exist, best professional judgment should be used
to select the one data set that most accurately reflects or estimates
background concentrations. Pollutant degradation and transport
information may be considered when utilizing pollutant loading data.
c. Calculation requirements. Except as provided below, the
representative background concentration for a pollutant in the specified
watershed, waterbody or waterbody segment shall be established on a
case-by-case basis as the geometric mean of:
i. Acceptable available water column data; or
ii. Water column concentrations estimated through use of acceptable
available caged or resident fish tissue data; or
iii. Water column concentrations estimated through use of acceptable
available or projected pollutant loading data.
d. Detection considerations.
i. Commonly accepted statistical techniques shall be used to
evaluate data sets consisting of values both above and below the
detection level.
ii. When all of the acceptable available data in a data set or
category, such as water column, caged or resident fish tissue or
pollutant loading data, are below the level of detection for a
pollutant, then all the data for that pollutant in that data set shall
be assumed to be zero.
10. Effluent Flow. If WLAs are expressed as concentrations of
pollutants, the TMDL shall also indicate the point source effluent flows
assumed in the analyses. Mass loading limitations established in NPDES
permits must be consistent with both the WLA and assumed effluent flows
used in establishing the TMDL.
11. Reserved Allocations. TMDLs may include reserved allocations of
loading capacity to accommodate future growth and additional sources.
Where such reserved allocations are not included in a TMDL, any
increased loadings of the pollutant for which the TMDL was developed
that are due to a new or expanded discharge shall not be allowed unless
the TMDL is revised in accordance with these proceudres to include an
allocation for the new or expanded discharge.
C. Mixing Zones for Bioaccumulative Chemicals of Concern (BCCs). The
following requirements shall be applied in establishing TMDLs, WLAs in
the absence of TMDLs, and preliminary WLAs for purposes of determining
the need for WQBELs under procedure 5 of appendix F, for BCCs:
1. There shall be no mixing zones available for new discharges of
BCCs to the Great Lakes System. WLAs established through TMDLs, WLAs in
the absence of TMDLs, and preliminary WLAs for purposes of determining
the need for WQBELs for new discharges of BCCs shall be set no higher
than the most stringent applicable water quality criteria or values for
the BCCs in question. This prohibition takes effect for a Great Lakes
State or Tribe on the date EPA approves the State's or Tribe's
submission of such prohibition or publishes a notice under 40 CFR
132.5(f) identifying that prohibition as applying to discharges within
the State or Federal Tribal reservation.
2. For purposes of section C of procedure 3 of appendix F, new
discharges are defined as: (1) A ``discharge of pollutants'' (as defined
in 40 CFR 122.2) to the Great Lakes System from a building, structure,
facility, or installation, the construction of which commences after the
date the prohibition in section C.1
[[Page 533]]
takes effect in that State or Tribe; (2) a new discharge from an
existing Great Lakes discharger that commences after the date the
prohibition in section C.1 takes effect in that State or Tribe; or (3)
an expanded discharge from an existing Great Lakes discharger that
commences after the date the prohibition in section C.1 takes effect in
that State or Tribe, except for those expanded discharges resulting from
changes in loadings of any BCC within the existing capacity and
processes (e.g., normal operational variability, changes in intake water
pollutants, increasing the production hours of the facility or adding
additional shifts, or increasing the rate of production), and that are
covered by the existing applicable control document. Not included within
the definition of ``new discharge'' are new or expanded discharges of
BCCs from a publicly owned treatment works (POTW as defined at 40 CFR
122.2) when such discharges are necessary to prevent a public health
threat to the community (e.g., a situation where a community with
failing septic systems is connected to a POTW to avert a potential
public health threat from these failing systems). These and all other
discharges of BCCs are defined as existing discharges.
3. Up until November 15, 2010, mixing zones for BCCs may be allowed
for existing discharges to the Great Lakes System pursuant to the
procedures specified in sections D and E of this procedure.
4. Except as provided in sections C.5 and C.6 of this procedure,
permits issued on or after this provision takes effect in a Great Lakes
State or Tribe shall not authorize mixing zones for existing discharges
of BCCs to the Great Lakes System after November 15, 2010. After
November 15, 2010, WLAs established through TMDLs, WLAs established in
the absence of TMDLs, and preliminary WLAs for purposes of determining
the need for WQBELs under procedure 5 of appendix F for existing
discharges of BCCs to the Great Lakes System shall be equal to the most
stringent applicable water quality criteria or values for the BCCs in
question.
5. Exception for Water Conservation. Great Lakes States and Tribes
may grant mixing zones for any existing discharge of BCCs to the Great
Lakes System beyond the date specified in section C.4 of this procedure
where it can be demonstrated, on a case-by-case basis, that failure to
grant a mixing zone would preclude water conservation measures that
would lead to overall load reductions in BCCs, even though higher
concentrations of BCCs occur in the effluent. Such mixing zones must
also be consistent with sections D and E of this procedure.
6. Exception for Technical and Economic Considerations. Great Lakes
States and Tribes may grant mixing zones beyond the date specified in
section C.4 of this procedure for any existing discharge of a BCC to the
Great Lakes System upon the request of a discharger, subject to sections
C.6.a through C.6.c below.
a. The State or Tribe must determine that:
i. The discharger is in compliance with and will continue to
implement, for the BCC in question, all applicable requirements of Clean
Water Act sections 118, 301, 302, 303, 304, 306, 307, 401, and 402,
including existing National Pollutant Discharge Elimination System
(NPDES) water-quality based effluent limitations; and
ii. The discharger has reduced and will continue to reduce the
loading of the BCC for which a mixing zone is requested to the maximum
extent possible, such that any additional controls or pollution
prevention measures to reduce or ultimately eliminate the BCC discharge
would result in unreasonable economic effects on the discharger or the
affected community because the controls or measures are not feasible or
cost-effective.
b. Any mixing zone established pursuant to this section shall:
i. Not result in any less stringent limitations than those existing
prior to November 13, 2000;
ii. Be no larger than necessary to account for the technical
constraints and economic effects identified pursuant to paragraph
C.6.a.ii above;
iii. Meet all applicable acute and chronic aquatic life, wildlife
and human health criteria and values within and at the edge of the
mixing zone or be consistent with the applicable TMDL or assessment and
remediation plan authorized under procedure 3.A.
iv. Be accompanied, as appropriate, by a permit condition requiring
the discharger to implement an ambient monitoring plan to ensure
compliance with water quality standards and consistency with any
applicable TMDL or such other strategy consistent with Section A of this
procedure, including the evaluation of alternative means for reducing
the BCC from other sources in the watershed; and
v. Be limited to one permit term unless the permitting authority
makes a new determination in accordance with this section for each
successive permit application in which a mixing zone for the BCC is
sought.
c. For each draft NPDES permit that would allow a mixing zone for
one or more BCCs after November 15, 2010, the fact sheet or statement of
basis for the draft permit that is required to be made available through
public notice under 40 CFR 124.6(e) shall:
i. Specify the mixing provisions used in calculating the permit
limits; and
ii. Identify each BCC for which a mixing zone is proposed.
7. Any mixing zone authorized under sections C.3, C.5 or C.6 must be
consistent with sections D and E of this procedure, as applicable.
[[Page 534]]
D. Deriving TMDLs, WLAs, and LAs for Point and Nonpoint Sources:
WLAs in the Absence of a TMDL; and Preliminary WLAs for Purposes of
Determining the Need for WQBELs for OWGL. This section addresses
conditions for deriving TMDLs for Open Waters of the Great Lakes (OWGL),
inland lakes and other waters of the Great Lakes System with no
appreciable flow relative to their volumes. State and Tribal procedures
to derive TMDLs under this section must be consistent with (as
protective as) the general conditions in section B of this procedure,
CWA section 303(d), existing regulations (40 CFR 130.7), section C of
this procedure, and sections D.1. through D.4 below. State and Tribal
procedures to derive WLAs calculated in the absence of a TMDL and
preliminary WLAs for purposes of determining the need for WQBELs under
procedure 5 of appendix F must be consistent with sections B.9, C.1, C3
through C.6, and D. 1 through D.4 of this procedure.
1. Individual point source WLAs and preliminary WLAs for purposes of
determining the need for WQBELs under procedure 5 of appendix F shall
assume no greater dilution than one part effluent to 10 parts receiving
water for implementation of numeric and narrative chronic criteria and
values (including, but not limited to human cancer criteria, human
cancer values, human noncancer values, human noncancer criteria,
wildlife criteria, and chronic aquatic life criteria and values) unless
an alternative mixing zone is demonstrated as appropriate in a mixing
zone demonstration conducted pursuant to section F of this procedure. In
no case shall a mixing zone be granted that exceeds the area where
discharge-induced mixing occurs.
2. Appropriate mixing zone assumptions to be used in calculating
load allocations for nonpoint sources shall be determined, consistent
with applicable State or Tribal requirements, on a case-by-case basis.
3. WLAs and preliminary WLAs based on acute aquatic life criteria or
values shall not exceed the Final Acute Value (FAV), unless a mixing
zone demonstration is conducted and approved pursuant to section F of
this procedure. If mixing zones from two or more proximate sources
interact or overlap, the combined effect must be evaluated to ensure
that applicable criteria and values will be met in the area where acute
mixing zones overlap.
4. In no case shall a mixing zone be granted that would likely
jeopardize the continued existence of any endangered or threatened
species listed under section 4 of the ESA or result in the destruction
or adverse modification of such species' critical habitat.
E. Deriving TMDLs, WLAs, and LAs for Point and Nonpoint Sources;
WLAs in the Absence of a TMDL; and Preliminary WLAs for the Purposes of
Determining the Need for WQBELs for Great Lakes Systems Tributaries and
Connecting Channels. This section describes conditions for deriving
TMDLs for tributaries and connecting channels of the Great Lakes System
that exhibit appreciable flows relative to their volumes. State and
Tribal procedures to derive TMDLs must be consistent with the general
conditions listed in section B of this procedure, section C of this
procedure, existing TMDL regulations (40 CFR 130.7) and specific
conditions E.1 through E.5. State and Tribal procedures to derive WLAs
calculated in the absence of a TMDL, and preliminary WLAs for purposes
of determining reasonable potential under procedure 5 of this appendix
for discharges to tributaries and connecting channels must be consistent
with sections B.9, C.1, C.3 through C.6, and E.1 through E.5 of this
procedure.
1. Stream Design. These design flows must be used unless data exist
to demonstrate that an alternative stream design flow is appropriate for
stream-specific and pollutant-specific conditions. For purposes of
calculating a TMDL, WLAs in the absence of a TMDL, or preliminary WLAs
for the purposes of determining reasonable potential under procedure 5
of this appendix, using a steady-state model, the stream design flows
shall be:
a. The 7-day, 10-year stream design flow (7Q10), or the 4-day, 3-
year biologically-based stream design flow for chronic aquatic life
criteria or values;
b. The 1-day, 10-year stream design flow (1Q10), for acute aquatic
life criteria or values;
c. The harmonic mean flow for human health criteria or values;
d. The 90-day, 10-year flow (90Q10) for wildlife criteria.
e. TMDLs, WLAs in the absence of TMDLs, and preliminary WLAs for the
purpose of determining the need for WQBELs calculated using dynamic
modelling do not need to incorporate the stream design flows specified
in sections E.1.a through E.1.d of this procedure.
2. Loading Capacity. The loading capacity is the greatest amount of
loading that a water can receive without violating water quality
standards. The loading capacity is initially calculated at the farthest
downstream location in the watershed drainage basin. The maximum
allowable loading consistent with the attainment of each applicable
numeric criterion or value for a given pollutant is determined by
multiplying the applicable criterion or value by the flow at the
farthest downstream location in the tributary basin at the design flow
condition described above. This loading is then compared to the loadings
at sites within the basin to assure that applicable numeric criteria or
values for a given pollutant are not exceeded at all applicable sites.
The lowest load is then selected as the loading capacity.
[[Page 535]]
3. Polluant Degradation. TMDLs, WLAs in the absence of a TMDL and
preliminary WLAs for purposes of determining the need for WQBELs under
procedure 5 of appendix F shall be based on the assumption that a
pollutant does not degrade. However, the regulatory authority may take
into account degradation of the pollutant if each of the following
conditions are met.
a. Scientifically valid field studies or other relevant information
demonstrate that degradation of the pollutant is expected to occur under
the full range of environmental conditions expected to be encountered;
b. Scientifically valid field studies or other relevant information
address other factors that affect the level of pollutants in the water
column including, but not limited to, resuspension of sediments,
chemical speciation, and biological and chemical transformation.
4. Acute Aquatic Life Criteria and Values. WLAs and LAs established
in a TMDL, WLAs in the absence of a TMDL, and preliminary WLAs for the
purpose of determining the need for WQBELs based on acute aquatic life
criteria or values shall not exceed the FAV, unless a mixing zone
demonstration is completed and approved pursuant to section F of this
procedure. If mixing zones from two or more proximate sources interact
or overlap, the combined effect must be evaluated to ensure that
applicable criteria and values will be met in the area where any
applicable acute mixing zones overlap. This acute WLA review shall
include, but not be limited to, consideration of:
a. The expected dilution under all effluent flow and concentration
conditions at stream design flow;
b. Maintenance of a zone of passage for aquatic organisms; and
c. Protection of critical aquatic habitat.
In no case shall a permitting authority grant a mixing zone that
would likely jeopardize the continued existence of any endangered or
threatened species listed under section 4 of the ESA or result in the
destruction or adverse modification of such species' critical habitat.
5. Chronic Mixing Zones. WLAs and LAs established in a TMDL, WLAs in
the absence of a TMDL, and preliminary WLAs for the purposes of
determining the need for WQBELs for protection of aquatic life, wildlife
and human health from chronic effects shall be calculated using a
dilution fraction no greater than 25 percent of the stream design flow
unless a mixing zone demonstration pursuant to section F of this
procedure is conducted and approved. A demonstration for a larger mixing
zone may be provided, if approved and implemented in accordance with
section F of this procedure. In no case shall a permitting authority
grant a mixing zone that would likely jeopardize the continued existence
of any endangered or threatened species listed under section 4 of the
ESA or result in the destruction or adverse modification of such
species' critical habitat.
F. Mixing Zone Demonstration Requirements.
1. For purposes of establishing a mixing zone other than as
specified in sections D and E above, a mixing zone demonstration must:
a. Describe the amount of dilution occurring at the boundaries of
the proposed mixing zone and the size, shape, and location of the area
of mixing, including the manner in which diffusion and dispersion occur;
b. For sources discharging to the open waters of the Great Lakes
(OWGLs), define the location at which discharge-induced mixing ceases;
c. Document the substrate character and geomorphology within the
mixing zone;
d. Show that the mixing zone does not interfere with or block
passage of fish or aquatic life;
e. Show that the mixing zone will be allowed only to the extent that
the level of the pollutant permitted in the waterbody would not likely
jeopardize the continued existence of any endangered or threatened
species listed under section 4 of the ESA or result in the destruction
or adverse modification of such species' critical habitat;
f. Show that the mixing zone does not extend to drinking water
intakes;
g. Show that the mixing zone would not otherwise interfere with the
designated or existing uses of the receiving water or downstream waters;
h. Document background water quality concentrations;
i. Show that the mixing zone does not promote undesirable aquatic
life or result in a dominance of nuisance species; and
j. Provide that by allowing additional mixing/dilution:
i. Substances will not settle to form objectionable deposits;
ii. Floating debris, oil, scum, and other matter in concentrations
that form nuisances will not be produced; and
iii. Objectionable color, odor, taste or turbidity will not be
produced.
2. In addition, the mixing zone demonstration shall address the
following factors:
a. Whether or not adjacent mixing zones overlap;
b. Whether organisms would be attracted to the area of mixing as a
result of the effluent character; and
c. Whether the habitat supports endemic or naturally occurring
species.
3. The mixing zone demonstration must be submitted to EPA for
approval. Following approval of a mixing zone demonstration consistent
with sections F.1 and F.2, adjustment to the dilution ratio specified in
section D.1 of this procedure shall be limited to the dilution available
in the area where discharger-induced mixing occurs.
[[Page 536]]
4. The mixing zone demonstration shall be based on the assumption
that a pollutant does not degrade within the proposed mixing zone,
unless:
a. Scientifically valid field studies or other relevant information
demonstrate that degradation of the pollutant is expected to occur under
the full range of environmental conditions expected to be encountered;
and
b. Scientifically valid field studies or other relevant information
address other factors that affect the level of pollutants in the water
column including, but not limited to, resuspension of sediments,
chemical speciation, and biological and chemical transformation.
Procedure 4: Additivity
The Great Lakes States and Tribes shall adopt additivity provisions
consistent with (as protective as) this procedure.
A. The Great Lakes States and Tribes shall adopt provisions to
protect human health from the potential adverse additive effects from
both the noncarcinogenic and carcinogenic components of chemical
mixtures in effluents. For the chlorinated dibenzo-p-dioxins (CDDs) and
chlorinated dibenzofurans (CDFs) listed in Table 1, potential adverse
additive effects in effluents shall be accounted for in accordance with
section B of this procedure.
B. Toxicity Equivalency Factors (TEFs)/Bioaccumulation Equivalency
Factors (BEFs).
1. The TEFs in Table 1 and BEFs in Table 2 shall be used when
calculating a 2,3,7,8-TCDD toxicity equivalence concentration in
effluent to be used when implementing both human health noncancer and
cancer criteria. The chemical concentration of each CDDs and CDFs in
effluent shall be converted to a 2,3,7,8-TCDD toxicity equivalence
concentration in effluent by (a) multiplying the chemical concentration
of each CDDs and CDFs in the effluent by the appropriate TEF in Table 1
below, (b) multiplying each product from step (a) by the BEF for each
CDDs and CDFs in Table 2 below, and (c) adding all final products from
step (b). The equation for calculating the 2,3,7,8-TCDD toxicity
equivalence concentration in effluent is:
[GRAPHIC] [TIFF OMITTED] TR23MR95.118
where:
(TEC)tcdd=2,3,7,8-TCDD toxicity equivalence concentration in
effluent
(C)x=concentration of total chemical x in effluent
(TEF)x=TCDD toxicity equivalency factor for x
(BEF)x=TCDD bioaccumulation equivalency factor for x
2. The 2,3,7,8-TCDD toxicity equivalence concentration in effluent
shall be used when developing waste load allocations under procedure 3,
preliminary waste load allocations for purposes of determining
reasonable potential under procedure 5, and for purposes of establishing
effluent quality limits under procedure 5.
Table 1--Toxicity Equivalency Factors for CDDs and CDFs
------------------------------------------------------------------------
Congener TEF
------------------------------------------------------------------------
2,3,7,8-TCDD............................................... 1.0
1,2,3,7,8-PeCDD............................................ 0.5
1,2,3,4,7,8-HxCDD.......................................... 0.1
1,2,3,6,7,8-HxCDD.......................................... 0.1
1,2,3,7,8,9-HxCDD.......................................... 0.1
1,2,3,4,6,7,8-HpCDD........................................ 0.01
OCDD....................................................... 0.001
2,3,7,8-TCDF............................................... 0.1
1,2,3,7,8-PeCDF............................................ 0.05
2,3,4,7,8-PeCDF............................................ 0.5
1,2,3,4,7,8-HxCDF.......................................... 0.1
1,2,3,6,7,8-HxCDF.......................................... 0.1
2,3,4,6,7,8-HxCDF.......................................... 0.1
1,2,3,7,8,9-HxCDF.......................................... 0.1
1,2,3,4,6,7,8-HpCDF........................................ 0.01
1,2,3,4,7,8,9-HpCDF........................................ 0.01
OCDF....................................................... 0.001
------------------------------------------------------------------------
Table 2--Bioaccumulation Equivalency Factors for CDDs and CDFs
------------------------------------------------------------------------
Congener BEF
------------------------------------------------------------------------
2,3,7,8-TCDD............................................... 1.0
1,2,3,7,8-PeCDD............................................ 0.9
1,2,3,4,7,8-HxCDD.......................................... 0.3
1,2,3,6,7,8-HxCDD.......................................... 0.1
1,2,3,7,8,9-HxCDD.......................................... 0.1
1,2,3,4,6,7,8-HpCDD........................................ 0.05
OCDD....................................................... 0.01
2,3,7,8-TCDF............................................... 0.8
1,2,3,7,8-PeCDF............................................ 0.2
2,3,4,7,8-PeCDF............................................ 1.6
1,2,3,4,7,8-HxCDF.......................................... 0.08
1,2,3,6,7,8-HxCDF.......................................... 0.2
2,3,4,6,7,8-HxCDF.......................................... 0.7
1,2,3,7,8,9-HxCDF.......................................... 0.6
1,2,3,4,6,7,8-HpCDF........................................ 0.01
1,2,3,4,7,8,9-HpCDF........................................ 0.4
OCDF....................................................... 0.02
------------------------------------------------------------------------
Procedure 5: Reasonable Potential To Exceed Water Quality Standards
Great Lakes States and Tribes shall adopt provisions consistent with
(as protective as) this procedure. If a permitting authority determines
that a pollutant is or may be discharged into the Great Lakes System at
a level which will cause, have the reasonable potential to cause, or
contribute to an excursion above any Tier I criterion or Tier II value,
the permitting authority shall incorporate a water quality-based
effluent limitation (WQBEL) in an NPDES permit for the discharge of that
pollutant. When facility-specific effluent monitoring data are
available, the permitting authority shall make
[[Page 537]]
this determination by developing preliminary effluent limitations (PEL)
and comparing those effluent limitations to the projected effluent
quality (PEQ) of the discharge in accordance with the following
procedures. In all cases, the permitting authority shall use any valid,
relevant, representative information that indicates a reasonable
potential to exceed any Tier I criterion or Tier II value.
A. Developing Preliminary Effluent Limitations on the Discharge of a
Pollutant From a Point Source.
1. The permitting authority shall develop preliminary wasteload
allocations (WLAs) for the discharge of the pollutant from the point
source to protect human health, wildlife, acute aquatic life, and
chronic aquatic life, based upon any existing Tier I criteria. Where
there is no Tier I criterion nor sufficient data to calculate a Tier I
criterion, the permitting authority shall calculate a Tier II value for
such pollutant for the protection of human health, and aquatic life and
the preliminary WLAs shall be based upon such values. Where there is
insufficient data to calculate a Tier II value, the permitting authority
shall apply the procedure set forth in section C of this procedure to
determine whether data must be generated to calculate a Tier II value.
2. The following provisions in procedure 3 of appendix F shall be
used as the basis for determining preliminary WLAs in accordance with
section 1 of this procedure: procedure 3.B.9, Background Concentrations
of Pollutants; procedure 3.C, Mixing Zones for Bioaccumulative Chemicals
of Concern (BCCs), procedures 3.C.1, and 3.C.3 through 3.C.6; procedure
3.D, Deriving TMDLs for Discharges to Lakes (when the receiving water is
an open water of the Great Lakes (OWGL), an inland lake or other water
of the Great Lakes System with no appreciable flow relative to its
volume); procedure 3.E, Deriving TMDLs, WLAs and Preliminary WLAs, and
load allocations (LAs) for Discharges to Great Lakes System Tributaries
(when the receiving water is a tributary or connecting channel of the
Great Lakes that exhibits appreciable flow relative to its volume); and
procedure 3.F, Mixing Zone Demonstration Requirements.
3. The permitting authority shall develop PELs consistent with the
preliminary WLAs developed pursuant to sections A.1 and A.2 of this
procedure, and in accordance with existing State or Tribal procedures
for converting WLAs into WQBELs. At a minimum:
a. The PELs based upon criteria and values for the protection of
human health and wildlife shall be expressed as monthly limitations;
b. The PELs based upon criteria and values for the protection of
aquatic life from chronic effects shall be expressed as either monthly
limitations or weekly limitations; and
c. The PELs based upon the criteria and values for the protection of
aquatic life from acute effects shall be expressed as daily limitations.
B. Determining Reasonable Potential Using Effluent Pollutant
Concentration Data.
If representative, facility-specific effluent monitoring data
samples are available for a pollutant discharged from a point source to
the waters of the Great Lakes System, the permitting authority shall
apply the following procedures:
1. The permitting authority shall specify the PEQ as the 95 percent
confidence level of the 95th percentile based on a log-normal
distribution of the effluent concentration; or the maximum observed
effluent concentration, whichever is greater. In calculating the PEQ,
the permitting authority shall identify the number of effluent samples
and the coefficient of variation of the effluent data, obtain the
appropriate multiplying factor from Table 1 of procedure 6 of appendix
F, and multiply the maximum effluent concentration by that factor. The
coefficient of variation of the effluent data shall be calculated as the
ratio of the standard deviation of the effluent data divided by the
arithmetic average of the effluent data, except that where there are
fewer than ten effluent concentration data points the coefficient of
variation shall be specified as 0.6. If the PEQ exceeds any of the PELs
developed in accordance with section A.3 of this procedure, the
permitting authority shall establish a WQBEL in a NPDES permit for such
pollutant.
2. In lieu of following the procedures under section B.1 of this
procedure, the permitting authority may apply procedures consistent with
the following:
a. The permitting authority shall specify the PEQ as the 95th
percentile of the distribution of the projected population of daily
values of the facility-specific effluent monitoring data projected using
a scientifically defensible statistical method that accounts for and
captures the long-term daily variability of the effluent quality,
accounts for limitations associated with sparse data sets and, unless
otherwise shown by the effluent data set, assumes a lognormal
distribution of the facility-specific effluent data. If the PEQ exceeds
the PEL based on the criteria and values for the protection of aquatic
life from acute effects developed in accordance with section A.3 of this
procedure, the permitting authority shall establish a WQBEL in an NPDES
permit for such pollutant;
b. The permitting authority shall calculate the PEQ as the 95th
percentile of the distribution of the projected population of monthly
averages of the facility-specific effluent monitoring data using a
scientifically defensible statistical method that accounts for and
captures the long-term variability of the monthly average effluent
quality, accounts for limitations associated with sparse
[[Page 538]]
data sets and, unless otherwise shown by the effluent data set, assumes
a lognormal distribution of the facility-specific effluent data. If the
PEQ exceeds the PEL based on criteria and values for the protection of
aquatic life from chronic effects, human health or wildlife developed in
accordance with section A.3 of this procedure, the permitting authority
shall establish a WQBEL in an NPDES permit for such pollutant; and
c. The permitting authority shall calculate the PEQ as the 95th
percentile of the distribution of the projected population of weekly
averages of the facility-specific effluent monitoring data using a
scientifically defensible statistical method that accounts for and
captures the long-term variability of the weekly average effluent
quality, accounts for limitations associated with sparse data sets and,
unless otherwise shown by the effluent data set, assumes a lognormal
distribution of the facility-specific effluent data. If the PEQ exceeds
the PEL based on criteria and values to protect aquatic life from
chronic effects developed in accordance with section A.3 of this
procedure, the permitting authority shall establish a WQBEL in an NPDES
permit for such pollutant.
C. Developing Necessary Data to Calculate Tier II Values Where Such
Data Does Not Currently Exist.
1. Except as provided in sections C.2, C.4, or D of this procedure,
for each pollutant listed in Table 6 of part 132 that a permittee
reports as known or believed to be present in its effluent, and for
which pollutant data sufficient to calculate Tier II values for non-
cancer human health, acute aquatic life and chronic aquatic life do not
exist, the permitting authority shall take the following actions:
a. The permitting authority shall use all available, relevant
information, including Quantitative Structure Activity Relationship
information and other relevant toxicity information, to estimate ambient
screening values for such pollutant which will protect humans from
health effects other than cancer, and aquatic life from acute and
chronic effects.
b. Using the procedures specified in sections A.1 and A.2 of this
procedure, the permitting authority shall develop preliminary WLAs for
the discharge of the pollutant from the point source to protect human
health, acute aquatic life, and chronic aquatic life, based upon the
estimated ambient screening values.
c. The permitting authority shall develop PELs in accordance with
section A.3 of this procedure, which are consistent with the preliminary
WLAs developed in accordance with section C.1.b of this procedure.
d. The permitting authority shall compare the PEQ developed
according to the procedures set forth in section B of this procedure to
the PELs developed in accordance with section C.1.c of this procedure.
If the PEQ exceeds any of the PELs, the permitting authority shall
generate or require the permittee to generate the data necessary to
derive Tier II values for noncancer human health, acute aquatic life and
chronic aquatic life.
e. The data generated in accordance with section C.1.d of this
procedure shall be used in calculating Tier II values as required under
section A.1 of this procedure. The calculated Tier II value shall be
used in calculating the preliminary WLA and PEL under section A of this
procedure, for purposes of determining whether a WQBEL must be included
in the permit. If the permitting authority finds that the PEQ exceeds
the calculated PEL, a WQBEL for the pollutant or a permit limit on an
indicator parameter consistent with 40 CFR 122.44(d)(1)(vi)(C) must be
included in the permit.
2. With the exception of bioaccumulative chemicals of concern
(BCCs), a permitting authority is not required to apply the procedures
set forth in section C.1 of this procedure or include WQBELs to protect
aquatic life for any pollutant listed in Table 6 of part 132 discharged
by an existing point source into the Great Lakes System, if:
a. There is insufficient data to calculate a Tier I criterion or
Tier II value for aquatic life for such pollutant;
b. The permittee has demonstrated through a biological assessment
that there are no acute or chronic effects on aquatic life in the
receiving water; and
c. The permittee has demonstrated in accordance with procedure 6 of
this appendix that the whole effluent does not exhibit acute or chronic
toxicity.
3. Nothing in sections C.1 or C.2 of this procedure shall preclude
or deny the right of a permitting authority to:
a. Determine, in the absence of the data necessary to derive a Tier
II value, that the discharge of the pollutant will cause, have the
reasonable potential to cause, or contribute to an excursion above a
narrative criterion for water quality; and
b. Incorporate a WQBEL for the pollutant into an NPDES permit.
4. If the permitting authority develops a WQBEL consistent with
section C.3 of this procedure, and the permitting authority demonstrates
that the WQBEL developed under section C.3 of this procedure is at least
as stringent as a WQBEL that would have been based upon the Tier II
value or values for that pollutant, the permitting authority shall not
be obligated to generate or require the permittee to generate the data
necessary to derive a Tier II value or values for that pollutant.
D. Consideration of Intake Pollutants in Determining Reasonable
Potential.
1. General.
[[Page 539]]
a. Any procedures adopted by a State or Tribe for considering intake
pollutants in water quality-based permitting shall be consistent with
this section and section E.
b. The determinations under this section and section E shall be made
on a pollutant-by-pollutant, outfall-by-outfall, basis.
c. This section and section E apply only in the absence of a TMDL
applicable to the discharge prepared by the State or Tribe and approved
by EPA, or prepared by EPA pursuant to 40 CFR 130.7(d), or in the
absence of an assessment and remediation plan submitted and approved in
accordance with procedure 3.A. of appendix F. This section and section E
do not alter the permitting authority's obligation under 40 CFR
122.44(d)(vii)(B) to develop effluent limitations consistent with the
assumptions and requirements of any available WLA for the discharge,
which is part of a TMDL prepared by the State or Tribe and approved by
EPA pursuant to 40 CFR 130.7, or prepared by EPA pursuant to 40 CFR
130.7(d).
2. Definition of Same Body of Water.
a. This definition applies to this section and section E of this
procedure.
b. An intake pollutant is considered to be from the same body of
water as the discharge if the permitting authority finds that the intake
pollutant would have reached the vicinity of the outfall point in the
receiving water within a reasonable period had it not been removed by
the permittee. This finding may be deemed established if:
i. The background concentration of the pollutant in the receiving
water (excluding any amount of the pollutant in the facility's
discharge) is similar to that in the intake water;
ii. There is a direct hydrological connection between the intake and
discharge points; and
iii. Water quality characteristics (e.g., temperature, Ph, hardness)
are similar in the intake and receiving waters.
c. The permitting authority may also consider other site-specific
factors relevant to the transport and fate of the pollutant to make the
finding in a particular case that a pollutant would or would not have
reached the vicinity of the outfall point in the receiving water within
a reasonable period had it not been removed by the permittee.
d. An intake pollutant from groundwater may be considered to be from
the same body of water if the permitting authority determines that the
pollutant would have reached the vicinity of the outfall point in the
receiving water within a reasonable period had it not been removed by
the permittee, except that such a pollutant is not from the same body of
water if the groundwater contains the pollutant partially or entirely
due to human activity, such as industrial, commercial, or municipal
operations, disposed actions, or treatment processes.
e. An intake pollutant is the amount of a pollutant that is present
in waters of the United States (including groundwater as provided in
section D.2.d of this procedure) at the time it is withdrawn from such
waters by the discharger or other facility (e.g., public water supply)
supplying the discharger with intake water.
3. Reasonable Potential Determination.
a. The permitting authority may use the procedure described in this
section of procedure 5 in lieu of procedures 5.A through C provided the
conditions specified below are met.
b. The permitting authority may determine that there is no
reasonable potential for the discharge of an identified intake pollutant
or pollutant parameter to cause or contribute to an excursion above a
narrative or numeric water quality criterion within an applicable water
quality standard where a discharger demonstrates to the satisfaction of
the permitting authority (based upon information provided in the permit
application or other information deemed necessary by the permitting
authority) that:
i. The facility withdraws 100 percent of the intake water containing
the pollutant from the same body of water into which the discharge is
made;
ii. The facility does not contribute any additional mass of the
identified intake pollutant to its wastewater;
iii. The facility does not alter the identified intake pollutant
chemically or physically in a manner that would cause adverse water
quality impacts to occur that would not occur if the pollutants were
left in-stream;
iv. The facility does not increase the identified intake pollutant
concentration, as defined by the permitting authority, at the edge of
the mixing zone, or at the point of discharge if a mixing zone is not
allowed, as compared to the pollutant concentration in the intake water,
unless the increased concentration does not cause or contribute to an
excursion above an applicable water quality standard; and
v. The timing and location of the discharge would not cause adverse
water quality impacts to occur that would not occur if the identified
intake pollutant were left in-stream.
c. Upon a finding under section D.3.b of this procedure that a
pollutant in the discharge does not cause, have the reasonable potential
to cause, or contribute to an excursion above an applicable water
quality standard, the permitting authority is not required to include a
WQBEL for the identified intake pollutant in the facility's permit,
provided:
i. The NPDES permit fact sheet or statement of basis includes a
specific determination that there is no reasonable potential for the
discharge of an identified intake pollutant to cause or contribute to an
excursion
[[Page 540]]
above an applicable narrative or numeric water quality criterion and
references appropriate supporting documentation included in the
administrative record;
ii. The permit requires all influent, effluent, and ambient
monitoring necessary to demonstrate that the conditions in section D.3.b
of this procedure are maintained during the permit term; and
iii. The permit contains a reopener clause authorizing modification
or revocation and reissuance of the permit if new information indicates
changes in the conditions in section D.3.b of this procedure.
d. Absent a finding under section D.3.b of this procedure that a
pollutant in the discharge does not cause, have the reasonable potential
to cause, or contribute to an excursion above an applicable water
quality standard, the permitting authority shall use the procedures
under sections 5.A through C of this procedure to determine whether a
discharge causes, has the reasonable potential to cause, or contribute
to an excursion above an applicable narrative or numeric water quality
criterion.
E. Consideration of Intake Pollutants in Establishing WQBELs.
1. General. This section applies only when the concentration of the
pollutant of concern upstream of the discharge (as determined using the
provisions in procedure 3.B.9 of appendix F) exceeds the most stringent
applicable water quality criterion for that pollutant.
2. The requirements of sections D.1-D.2 of this procedure shall also
apply to this section.
3. Intake Pollutants from the Same Body of Water.
a. In cases where a facility meets the conditions in sections
D.3.b.i and D.3.b.iii through D.3.b.v of this procedure, the permitting
authority may establish effluent limitations allowing the facility to
discharge a mass and concentration of the pollutant that are no greater
than the mass and concentration of the pollutant identified in the
facility's intake water (``no net addition limitations''). The permit
shall specify how compliance with mass and concentration limitations
shall be assessed. No permit may authorize ``no net addition
limitations'' which are effective after March 23, 2007. After that date,
WQBELs shall be established in accordance with procedure 5.F.2 of
appendix F.
b. Where proper operation and maintenance of a facility's treatment
system results in removal of a pollutant, the permitting authority may
establish limitations that reflect the lower mass and/or concentration
of the pollutant achieved by such treatment, taking into account the
feasibility of establishing such limits.
c. For pollutants contained in intake water provided by a water
system, the concentration of the intake pollutant shall be determined at
the point where the raw water supply is removed from the same body of
water, except that it shall be the point where the water enters the
water supplier's distribution system where the water treatment system
removes any of the identified pollutants from the raw water supply. Mass
shall be determined by multiplying the concentration of the pollutant
determined in accordance with this paragraph by the volume of the
facility's intake flow received from the water system.
4. Intake Pollutants from a Different Body of Water. Where the
pollutant in a facility's discharge originates from a water of the
United States that is not the same body of water as the receiving water
(as determined in accordance with section D.2 of this procedure), WQBELs
shall be established based upon the most stringent applicable water
quality criterion for that pollutant.
5. Multiple Sources of Intake Pollutants. Where a facility
discharges intake pollutants that originate in part from the same body
of water, and in part from a different body of water, the permitting
authority may apply the procedures of sections E.3 and E.4 of this
procedure to derive an effluent limitation reflecting the flow-weighted
average of each source of the pollutant, provided that adequate
monitoring to determine compliance can be established and is included in
the permit.
F. Other Applicable Conditions.
1. In addition to the above procedures, effluent limitations shall
be established to comply with all other applicable State, Tribal and
Federal laws and regulations, including technology-based requirements
and antidegradation policies.
2. Once the permitting authority has determined in accordance with
this procedure that a WQBEL must be included in an NPDES permit, the
permitting authority shall:
a. Rely upon the WLA established for the point source either as part
of any TMDL prepared under procedure 3 of this appendix and approved by
EPA pursuant to 40 CFR 130.7, or as part of an assessment and
remediation plan developed and approved in accordance with procedure 3.A
of this appendix, or, in the absence of such TMDL or plan, calculate
WLAs for the protection of acute and chronic aquatic life, wildlife and
human health consistent with the provisions referenced in section A.1 of
this procedure for developing preliminary wasteload allocations, and
b. Develop effluent limitations consistent with these WLAs in
accordance with existing State or Tribal procedures for converting WLAs
into WQBELs.
3. When determining whether WQBELs are necessary, information from
chemical-specific, whole effluent toxicity and biological
[[Page 541]]
assessments shall be considered independently.
4. If the geometric mean of a pollutant in fish tissue samples
collected from a waterbody exceeds the tissue basis of a Tier I
criterion or Tier II value, after consideration of the variability of
the pollutant's bioconcentration and bioaccumulation in fish, each
facility that discharges detectable levels of such pollutant to that
water has the reasonable potential to cause or contribute to an
excursion above a Tier I criteria or a Tier II value and the permitting
authority shall establish a WQBEL for such pollutant in the NPDES permit
for such facility.
Procedure 6: Whole Effluent Toxicity Requirements
The Great Lakes States and Tribes shall adopt provisions consistent
with (as protective as) procedure 6 of appendix F of part 132.
The following definitions apply to this part:
Acute toxic unit (TUa). 100/LC50 where the
LC50 is expressed as a percent effluent in the test medium of
an acute whole effluent toxicity (WET) test that is statistically or
graphically estimated to be lethal to 50 percent of the test organisms.
Chronic toxic unit (TUc). 100/NOEC or 100/
IC25, where the NOEC and IC25 are expressed as a
percent effluent in the test medium.
Inhibition concentration 25 (IC25). The toxicant
concentration that would cause a 25 percent reduction in a non-quantal
biological measurement for the test population. For example, the
IC25 is the concentration of toxicant that would cause a 25
percent reduction in mean young per female or in growth for the test
population.
No observed effect concentration (NOEC). The highest concentration
of toxicant to which organisms are exposed in a full life-cycle or
partial life-cycle (short-term) test, that causes no observable adverse
effects on the test organisms (i.e., the highest concentration of
toxicant in which the values for the observed responses are not
statistically significantly different from the controls).
A. Whole Effluent Toxicity Requirements. The Great Lakes States and
Tribes shall adopt whole effluent toxicity provisions consistent with
the following:
1. A numeric acute WET criterion of 0.3 acute toxic units
(TUa) measured pursuant to test methods in 40 CFR part 136,
or a numeric interpretation of a narrative criterion establishing that
0.3 TUa measured pursuant to test methods in 40 CFR part 136
is necessary to protect aquatic life from acute effects of WET. At the
discretion of the permitting authority, the foregoing requirement shall
not apply in an acute mixing zone that is sized in accordance with EPA-
approved State and Tribal methods.
2. A numeric chronic WET criterion of one chronic toxicity unit
(TUc) measured pursuant to test methods in 40 CFR part 136,
or a numeric interpretation of a narrative criterion establishing that
one TUc measured pursuant to test methods in 40 CFR part 136
is necessary to protect aquatic life from the chronic effects of WET. At
the discretion of the permitting authority, the foregoing requirements
shall not apply within a chronic mixing zone consistent with: (a)
procedures 3.D.1 and 3.D.4, for discharges to the open of the Great
Lakes (OWGL), inland lakes and other waters of the Great Lakes System
with no appreciable flow relative to their volume, or (b) procedure
3.E.5 for discharges to tributaries and connecting channels of the Great
Lakes System.
B. WET Test Methods. All WET tests performed to implement or
ascertain compliance with this procedure shall be performed in
accordance with methods established in 40 CFR part 136.
C. Permit Conditions.
1. Where a permitting authority determines pursuant to section D of
this procedure that the WET of an effluent is or may be discharged at a
level that will cause, have the reasonable potential to cause, or
contribute to an excursion above any numeric WET criterion or narrative
criterion within a State's or Tribe's water quality standards, the
permitting authority:
a. Shall (except as provided in section C.1.e of this procedure)
establish a water quality-based effluent limitation (WQBEL) or WQBELs
for WET consistent with section C.1.b of this procedure;
b. Shall calculate WQBELs pursuant to section C.1.a. of this
procedure to ensure attainment of the State's or Tribe's chronic WET
criteria under receiving water flow conditions described in procedures
3.E.1.a (or where applicable, with procedure 3.E.1.e) for Great Lakes
System tributaries and connecting channels, and with mixing zones no
larger than allowed pursuant to section A.2. of this procedure. Shall
calculate WQBELs to ensure attainment of the State's or Tribe's acute
WET criteria under receiving water flow conditions described in
procedure 3.E.1.b (or where applicable, with procedure 3.E.1.e) for
Great Lakes System tributaries and connecting channels, with an
allowance for mixing zones no greater than specified pursuant to section
A.1 of this procedure.
c. May specify in the NPDES permit the conditions under which a
permittee would be required to perform a toxicity reduction evaluation.
d. May allow with respect to any WQBEL established pursuant to
section C.1.a of this procedure an appropriate schedule of compliance
consistent with procedure 9 of appendix F; and
e. May decide on a case-by-case basis that a WQBEL for WET is not
necessary if the State's or Tribe's water quality standards do not
contain a numeric criterion for WET,
[[Page 542]]
and the permitting authority demonstrates in accordance with 40 CFR
122.44(d)(1)(v) that chemical-specific effluent limits are sufficient to
ensure compliance with applicable criteria.
2. Where a permitting authority lacks sufficient information to
determine pursuant to section D of this procedure whether the WET of an
effluent is or may be discharged at levels that will cause, have the
reasonable potential to cause, or contribute to an excursion above any
numeric WET criterion or narrative criterion within a State's or Tribe's
water quality standards, then the permitting authority should consider
including in the NPDES permit appropriate conditions to require
generation of additional data and to control toxicity if found, such as:
a. WET testing requirements to generate the data needed to
adequately characterize the toxicity of the effluent to aquatic life;
b. Language requiring a permit reopener clause to establish WET
limits if any toxicity testing data required pursuant to section C.2.a
of this procedure indicate that the WET of an effluent is or may be
discharged at levels that will cause, have the reasonable potential to
cause, or contribute to an excursion above any numeric WET criterion or
narrative criterion within a State's or Tribe's water quality standards.
3. Where sufficient data are available for a permitting authority to
determine pursuant to section D of this procedure that the WET of an
effluent neither is nor may be discharged at a level that will cause,
have the reasonable potential to cause, or contribute to an excursion
above any numeric WET criterion or narrative criterion within a State's
or Tribe's water quality standards, the permitting authority may include
conditions and limitations described in section C.2 of this procedure at
its discretion.
D. Reasonable Potential Determinations. The permitting authority
shall take into account the factors described in 40 CFR 122.44(d)(1)(ii)
and, where representative facility-specific WET effluent data are
available, apply the following requirements in determining whether the
WET of an effluent is or may be discharged at a level that will cause,
have the reasonable potential to cause, or contribute to an excursion
above any numeric WET criterion or narrative criterion within a State's
or Tribe's water quality standards.
1. The permitting authority shall characterize the toxicity of the
discharge by:
a. Either averaging or using the maximum of acute toxicity values
collected within the same day for each species to represent one daily
value. The maximum of all daily values for the most sensitive species
tested is used for reasonable potential determinations;
b. Either averaging or using the maximum of chronic toxicity values
collected within the same calendar month for each species to represent
one monthly value. The maximum of such values, for the most sensitive
species tested, is used for reasonable potential determinations:
c. Estimating the toxicity values for the missing endpoint using a
default acute-chronic ratio (ACR) of 10, when data exist for either
acute WET or chronic WET, but not for both endpoints.
2. The WET of an effluent is or may be discharged at a level that
will cause, have the reasonable potential to cause, or contribute to an
excursion above any numeric acute WET criterion or numeric
interpretation of a narrative criterion within a State's or Tribe's
water quality standards, when effluent-specific information demonstrates
that:
(TUa effluent) (B) (effluent flow/(Qad+effluent
flow))AC
Where TUa effluent is the maximum measured acute toxicity of
100 percent effluent determined pursuant to section D.1.a. of this
procedure, B is the multiplying factor taken from Table F6-1 of this
procedure to convert the highest measured effluent toxicity value to the
estimated 95th percentile toxicity value for the discharge, effluent
flow is the same effluent flow used to calculate the preliminary
wasteload allocations (WLAs) for individual pollutants to meet the acute
criteria and values for those pollutants, AC is the numeric acute WET
criterion or numeric interpretation of a narrative criterion established
pursuant to section A.1 of this procedure and expressed in
TUa, and Qad is the amount of the receiving water available
for dilution calculated using: (i) the specified design flow(s) for
tributaries and connecting channels in section C.1.b of this procedure,
or where appropriate procedure 3.E.1.e of appendix F, and using EPA-
approved State and Tribal procedures for establishing acute mixing zones
in tributaries and connecting channels, or (ii) the EPA-approved State
and Tribal procedures for establishing acute mixing zones in OWGLs.
Where there are less than 10 individual WET tests, the multiplying
factor taken from Table F6-1 of this procedure shall be based on a
coefficient of variation (CV) or 0.6. Where there are 10 or more
individual WET tests, the multiplying factor taken from Table F6-1 shall
be based on a CV calculated as the standard deviation of the acute
toxicity values found in the WET tests divided by the arithmetic mean of
those toxicity values.
3. The WET of an effluent is or may be discharged at a level that
will cause, have the reasonable potential to cause, or contribute to an
excursion above any numeric chronic WET criterion or numeric
interpretation of a narrative criterion within a State's or Tribe's
water quality standards, when effluent-specific information demonstrates
that:
(TUc effluent) (B) (effluent flow/Qad+effluent
flow))CC
[[Page 543]]
Where TUc effluent is the maximum measured chronic toxicity
value of 100 percent effluent determined in accordance with section
D.1.b. of this procedure, B is the multiplying factor taken from Table
F6-1 of this procedure, effluent flow is the same effluent flow used to
calculate the preliminary WLAs for individual pollutants to meet the
chronic criteria and values for those pollutants, CC is the numeric
chronic WET criterion or numeric interpretation of a narrative criterion
established pursuant to section A.2 of this procedure and expressed in
TUc, and Qad
is the amount of the receiving water available for dilution calculated
using: (i) the design flow(s) for tributaries and connecting channels
specified in procedure 3.E.1.a of appendix F, and where appropriate
procedure 3.E.1.e of appendix F, and in accordance with the provisions
of procedure 3.E.5 for chronic mixing zones, or (ii) procedures 3.D.1
and 3.D.4 for discharges to the OWGLs. Where there are less than 10
individual WET tests, the multiplying factor taken from Table F6-1 of
this procedure shall be based on a CV of 0.6. Where there are 10 more
individual WET tests, the multiplying factor taken from Table F6-1 of
this procedure shall be based on a CV calculated as the standard
deviation of the WET tests divided by the arithmetic mean of the WET
tests.
Table F6-1--Reasonable Potential Multiplying Factors: 95% Confidence Level and 95% Probability Basis
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Coefficient of variation
Number of Samples -------------------------------------------------------------------------------------------------------------------------------------------
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.0
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
1................................................... 1.4 1.9 2.6 3.6 4.7 6.2 8.0 10.1 12.6 15.5 18.7 22.3 26.4 30.8 35.6 40.7 46.2 52.1 58.4 64.9
2................................................... 1.3 1.6 2.0 2.5 3.1 3.8 4.6 5.4 6.4 7.4 8.5 9.7 10.9 12.2 13.6 15.0 16.4 17.9 19.5 21.1
3................................................... 1.2 1.5 1.8 2.1 2.5 3.0 3.5 4.0 4.6 5.2 5.8 6.5 7.2 7.9 8.6 9.3 10.0 10.8 11.5 12.3
4................................................... 1.2 1.4 1.7 1.9 2.2 2.6 2.9 3.3 3.7 4.2 4.6 5.0 5.5 6.0 6.4 6.9 7.4 7.8 8.3 8.8
5................................................... 1.2 1.4 1.6 1.8 2.1 2.3 2.6 2.9 3.2 3.6 3.9 4.2 4.5 4.9 5.2 5.6 5.9 6.2 6.6 6.9
6................................................... 1.1 1.3 1.5 1.7 1.9 2.1 2.4 2.6 2.9 3.1 3.4 3.7 3.9 4.2 4.5 4.7 5.0 5.2 5.5 5.7
7................................................... 1.1 1.3 1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.8 3.1 3.3 3.5 3.7 3.9 4.1 4.3 4.5 4.7 4.9
8................................................... 1.1 1.3 1.4 1.6 1.7 1.9 2.1 2.3 2.4 2.6 2.8 3.0 3.2 3.3 3.5 3.7 3.9 4.0 4.2 4.3
9................................................... 1.1 1.2 1.4 1.5 1.7 1.8 2.0 2.1 2.3 2.4 2.6 2.8 2.9 3.1 3.2 3.4 3.5 3.6 3.8 3.9
10.................................................. 1.1 1.2 1.3 1.5 1.6 1.7 1.9 2.0 2.2 2.3 2.4 2.6 2.7 2.8 3.0 3.1 3.2 3.3 3.4 3.6
11.................................................. 1.1 1.2 1.3 1.4 1.6 1.7 1.8 1.9 2.1 2.2 2.3 2.4 2.5 2.7 2.8 2.9 3.0 3.1 3.2 3.3
12.................................................. 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.9 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 3.0 3.0
13.................................................. 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.0 2.1 2.2 2.3 2.4 2.5 2.5 2.6 2.7 2.8 2.9
14.................................................. 1.1 1.2 1.3 1.4 1.4 1.5 1.6 1.7 1.8 1.9 2.0 2.1 2.2 2.3 2.3 2.4 2.5 2.6 2.6 2.7
15.................................................. 1.1 1.2 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.8 1.9 2.0 2.1 2.2 2.2 2.3 2.4 2.4 2.5 2.5
16.................................................. 1.1 1.1 1.2 1.3 1.4 1.5 1.6 1.6 1.7 1.8 1.9 1.9 2.0 2.1 2.1 2.2 2.3 2.3 2.4 2.4
17.................................................. 1.1 1.1 1.2 1.3 1.4 1.4 1.5 1.6 1.7 1.7 1.8 1.9 1.9 2.0 2.0 2.1 2.2 2.2 2.3 2.3
18.................................................. 1.1 1.1 1.2 1.3 1.3 1.4 1.5 1.6 1.6 1.7 1.7 1.8 1.9 1.9 2.0 2.0 2.1 2.1 2.2 2.2
19.................................................. 1.1 1.1 1.2 1.3 1.3 1.4 1.5 1.5 1.6 1.6 1.7 1.8 1.8 1.9 1.9 2.0 2.0 2.0 2.1 2.1
20.................................................. 1.1 1.1 1.2 1.2 1.3 1.4 1.4 1.5 1.5 1.6 1.6 1.7 1.7 1.8 1.8 1.9 1.9 2.0 2.0 2.0
30.................................................. 1.0 1.1 1.1 1.1 1.2 1.2 1.2 1.3 1.3 1.3 1.3 1.4 1.4 1.4 1.4 1.5 1.5 1.5 1.5 1.5
40.................................................. 1.0 1.0 1.1 1.1 1.1 1.1 1.1 1.1 1.2 1.2 1.2 1.2 1.2 1.2 1.2 1.2 1.2 1.2 1.3 1.3
50.................................................. 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.1 1.1 1.1 1.1 1.1 1.1 1.1 1.1 1.1 1.1 1.1 1.1 1.1
60.................................................. 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0
70.................................................. 1.0 1.0 1.0 1.0 1.0 0.9 0.9 0.9 0.9 0.9 0.9 0.9 0.9 0.9 0.9 0.9 0.9 0.9 0.9 0.9
80.................................................. 1.0 1.0 1.0 0.9 0.9 0.9 0.9 0.9 0.9 0.9 0.9 0.9 0.9 0.9 0.8 0.8 0.8 0.8 0.8 0.8
90.................................................. 1.0 1.0 0.9 0.9 0.9 0.9 0.9 0.9 0.9 0.8 0.8 0.8 0.8 0.8 0.8 0.8 0.8 0.8 0.8 0.8
100................................................. 1.0 1.0 0.9 0.9 0.9 0.9 0.9 0.8 0.8 0.8 0.8 0.8 0.8 0.8 0.8 0.8 0.8 0.7 0.7 0.7
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Procedure 7: Loading Limits
The Great Lakes States and Tribes shall adopt provisions consistent
with (as protective as) this procedure.
Whenever a water quality-based effluent limitation (WQBEL) is
developed, the WQBEL shall be expressed as both a concentration value
and a corresponding mass loading rate.
A. Both mass and concentration limits shall be based on the same
permit averaging periods such as daily, weekly, or monthly averages, or
in other appropriate permit averaging periods.
B. The mass loading rates shall be calculated using effluent flow
rates that are consistent with those used in establishing the WQBELs
expressed in concentration.
Procedure 8: Water Quality-based Effluent Limitations Below the
Quantification Level
The Great Lakes States and Tribes shall adopt provisions consistent
with (as protective as) this procedure.
When a water quality-based effluent limitation (WQBEL) for a
pollutant is calculated to be less than the quantification level:
A. Permit Limits. The permitting authority shall designate as the
limit in the NPDES permit the WQBEL exactly as calculated.
[[Page 544]]
B. Analytical Method and Quantification Level.
1. The permitting authority shall specify in the permit the most
sensitive, applicable, analytical method, specified in or approved under
40 CFR part 136, or other appropriate method if one is not available
under 40 CFR part 136, to be used to monitor for the presence and amount
in an effluent of the pollutant for which the WQBEL is established; and
shall specify in accordance with section B.2 of this procedure, the
quantification level that can be achieved by use of the specified
analytical method.
2. The quantification level shall be the minimum level (ML)
specified in or approved under 40 CFR part 136 for the method for that
pollutant. If no such ML exists, or if the method is not specified or
approved under 40 CFR part 136, the quantification level shall be the
lowest quantifiable level practicable. The permitting authority may
specify a higher quantification level if the permittee demonstrates that
a higher quantification level is appropriate because of effluent-
specific matrix interference.
3. The permit shall state that, for the purpose of compliance
assessment, the analytical method specified in the permit shall be used
to monitor the amount of pollutant in an effluent down to the
quantification level, provided that the analyst has complied with the
specified quality assurance/quality control procedures in the relevant
method.
4. The permitting authority shall use applicable State and Tribal
procedures to average and account for monitoring data. The permitting
authority may specify in the permit the value to be used to interpret
sample values below the quantification level.
C. Special Conditions. The permit shall contain a reopener clause
authorizing modification or revocation and reissuance of the permit if
new information generated as a result of special conditions included in
the permit indicates that presence of the pollutant in the discharge at
levels above the WQBEL. Special conditions that may be included in the
permit include, but are not limited to, fish tissue sampling, whole
effluent toxicity (WET) tests, limits and/or monitoring requirements on
internal waste streams, and monitoring for surrogate parameters. Data
generated as a result of special conditions can be used to reopen the
permit to establish more stringent effluent limits or conditions, if
necessary.
D. Pollutant Minimization Program. The permitting authority shall
include a condition in the permit requiring the permittee to develop and
conduct a pollutant minimization program for each pollutant with a WQBEL
below the quantification level. The goal of the pollutant minimization
program shall be to maintain the effluent at or below the WQBEL. In
addition, States and Tribes may consider cost-effectiveness when
evaluating the requirements of a PMP. The pollutant minimization program
shall include, but is not limited to, the following:
1. An annual review and semi-annual monitoring of potential sources
of the pollutant, which may include fish tissue monitoring and other
bio-uptake sampling;
2. Quarterly monitoring for the pollutant in the influent to the
wastewater treatment system;
3. Submittal of a control strategy designed to proceed toward the
goal of maintaining the effluent below the WQBEL;
4. Implementation of appropriate, cost-effective control measures
consistent with the control strategy; and
5. An annual status report that shall be sent to the permitting
authority including:
a. All minimization program monitoring results for the previous
year;
b. A list of potential sources of the pollutant; and
c. A summary of all action undertaken pursuant to the control
strategy.
6. Any information generated as a result of procedure 8.D can be
used to support a request for subsequent permit modifications, including
revisions to (e.g., more or less frequent monitoring), or removal of the
requirements of procedure 8.D, consistent with 40 CFR 122.44, 122.62 and
122.63.
Procedure 9: Compliance Schedules
The Great Lakes States and Tribes shall adopt provisions consistent
with (as protective as) procedure 9 of appendix F of part 132.
A. Limitations for New Great Lakes Dischargers. When a permit issued
on or after March 23, 1997 to a new Great Lakes discharger (defined in
Part 132.2) contains a water quality-based effluent limitation (WQBEL),
the permittee shall comply with such a limitation upon the commencement
of the discharge.
B. Limitations for Existing Great Lakes Dischargers.
1. Any existing permit that is reissued or modified on or after
March 23, 1997 to contain a new or more restrictive WQBEL may allow a
reasonable period of time, up to five years from the date of permit
issuance or modification, for the permittee to comply with that limit,
provided that the Tier I criterion or whole effluent toxicity (WET)
criterion was adopted (or, in the case of a narrative criterion, Tier II
value, or Tier I criterion derived pursuant to the methodology in
appendix A of part 132, was newly derived) after July 1, 1977.
2. When the compliance schedule established under paragraph 1 goes
beyond the term of the permit, an interim permit limit effective upon
the expiration date shall be included in the permit and addressed in the
permit's fact sheet or statement of basis. The administrative record for
the permit
[[Page 545]]
shall reflect the final limit and its compliance date.
3. If a permit establishes a schedule of compliance under paragraph
1 which exceeds one year from the date of permit issuance or
modification, the schedule shall set forth interim requirements and
dates for their achievement. The time between such interim dates may not
exceed one year. If the time necessary for completion of any interim
requirement is more than one year and is not readily divisible into
stages for completion, the permit shall require, at a minimum, specified
dates for annual submission of progress reports on the status of any
interim requirements.
C. Delayed Effectiveness of Tier II Limitations for Existing Great
Lakes Discharges.
1. Whenever a limit (calculated in accordance with Procedure 3)
based upon a Tier II value is included in a reissued or modified permit
for an existing Great Lakes discharger, the permit may provide a
reasonable period of time, up to two years, in which to provide
additional studies necessary to develop a Tier I criterion or to modify
the Tier II value. In such cases, the permit shall require compliance
with the Tier II limitation within a reasonable period of time, no later
than five years after permit issuance or modification, and contain a
reopener clause.
2. The reopener clause shall authorize permit modifications if
specified studies have been completed by the permittee or provided by a
third-party during the time allowed to conduct the specified studies,
and the permittee or a third-party demonstrates, through such studies,
that a revised limit is appropriate. Such a revised limit shall be
incorporated through a permit modification and a reasonable time period,
up to five years, shall be allowed for compliance. If incorporated prior
to the compliance date of the original Tier II limitation, any such
revised limit shall not be considered less-stringent for purposes of the
anti-backsliding provisions of section 402(o) of the Clean Water Act.
3. If the specified studies have been completed and do not
demonstrate that a revised limit is appropriate, the permitting
authority may provide a reasonable additional period of time, not to
exceed five years with which to achieve compliance with the original
effluent limitation.
4. Where a permit is modified to include new or more stringent
limitations, on a date within five years of the permit expiration date,
such compliance schedules may extend beyond the term of a permit
consistent with section B.2 of this procedure.
5. If future studies (other than those conducted under paragraphs 1,
2, or 3 above) result in a Tier II value being changed to a less
stringent Tier II value or Tier I criterion, after the effective date of
a Tier II-based limit, the existing Tier II-based limit may be revised
to be less stringent if:
(a) It complies with sections 402(o) (2) and (3) of the CWA; or,
(b) In non-attainment waters, where the existing Tier II limit was
based on procedure 3, the cumulative effect of revised effluent
limitation based on procedure 3 of this appendix will assure compliance
with water quality standards; or,
(c) In attained waters, the revised effluent limitation complies
with the State or Tribes' antidegradation policy and procedures.
[60 FR 15387, Mar. 23, 1995, as amended at 63 FR 20110, Apr. 23, 1998;
65 FR 67650, Nov. 13, 2000]