Code of Maine Rules
06 - DEPARTMENT OF ENVIRONMENTAL PROTECTION
096 - DEPARTMENT OF ENVIRONMENTAL PROTECTION - GENERAL
Chapter 584 - SURFACE WATER QUALITY CRITERIA FOR TOXIC POLLUTANTS
Appendix 096-584-A

Current through 2024-38, September 18, 2024

Statewide criteria for toxic pollutants with national water quality criteria for Priority Pollutants and non Priority Pollutants. "FR Cite/Source" refers to the EPA publication from which the criteria are derived. The "Gold Book" is Quality Criteria for Water: 1986. EPA 440/5-86-001.

1. Table I. Criteria for Priority Pollutant listed pursuant to 304(a) of the Clean Water Act. See also the footnotes following this table.

Footnotes to Table I:

A. This recommended water quality criterion was derived from data for arsenic (III), but is applied here to total arsenic, which might imply that arsenic (III) and arsenic (V) are equally toxic to aquatic life and that their toxicities are additive. In the arsenic criteria document (EPA 440/5-84-033, January 1985), Species Mean Acute Values are given for both arsenic (III) and arsenic (V) for five species and the ratios of the SMAVs for each species range from 0.6 to 1.7. Chronic values are available for both arsenic (III) and arsenic (V) for one species; for the fathead minnow, the chronic value for arsenic (V) is 0.29 times the chronic value for arsenic (III). No data are known to be available concerning whether the toxicities of the forms of arsenic to aquatic organisms are additive.

B. This criterion has been revised to reflect The Environmental Protection Agency's q1* or RfD, as contained in the Integrated Risk Information System (IRIS) as of May 17, 2002. The fish tissue bioconcentration factor (BCF)from the 1980 Ambient Water Quality Criteria document was retained in each case.

E. The freshwater criterion for this metal is expressed as a function of hardness (mg/L) in the water column. The value given here corresponds to a hardness of 20 mg/L. Also see part 7 under "Additional Notes" after Table II.

F. Freshwater aquatic life values for pentachlorophenol are expressed as a function of pH, and are calculated as follows: CMC = exp(1.005(pH)-4.869);CCC = exp(1.005(pH)-5.134). Values displayed in table correspond to a pH of 7.0.

G. This Criterion is based on 304(a) aquatic life criterion issued in 1980, and was issued in one of the following documents: Aldrin/Dieldrin (EPA 440/5-80-019), Chlordane (EPA 440/5-80-027), DDT (EPA 440/5-80-038), Endosulfan(EPA440/5-80-046), Endrin(EPA440/5-047), Heptachlor(440/580-052), Hexachlorocyclohexane(EPA440/5-80-054), Silver (EPA 440/5-80-071). The Minimum Data Requirements and derivation procedures were different in the 1980 Guidelines than in the 1985 Guidelines. For example, a "CMC" derived using the 1980 Guidelines was derived to be used as an instantaneous maximum. If assessment is to be done using an averaging period, the values given should be divided by 2 to obtain a value that is more comparable to a CMC derived using the 1985 Guidelines.

I. This criterion for asbestos is the Maximum Contaminant Level (MCL) developed under the Safe Drinking Water Act.

J. These values are not applicable to bleach kraft pulp mills. See 38 M.R.S., section420(2)(I).

K. This recommended criterion is based on a 304(a) aquatic life criterion that was issued in the 1995 Updates: Water Quality Criteria Documents for the Protection of Aquatic Life in Ambient Water, (EPA-820-B-96-001, September 1996). This value was derived using the GLI Guidelines (60FR15393-15399, March 23, 1995; 40CFR 132 Appendix A); the difference between the 1985 Guidelines and the GLI Guidelines are explained on page iv of the 1995 Updates. None of the decisions concerning the derivation of this criterion were affected by any considerations that are specific to the Great Lakes.

L. The CMC = 1/[(f1/CMC1) + (f2/CMC2)] where f1 and f2 are the fractions of total selenium that are treated as selenite and selenate, respectively, and CMC1 and CMC2 are 185.9 µg/l and 12.83 µg/l, respectively.

M. EPA is currently reassessing the criteria for arsenic.

N. This criterion applies to total PCBs (e.g. the sum of all congener or all isomer or homolog or Aroclor analyses).

O. The derivation of the CCC for this pollutant did not consider exposure through the diet, which is probably important for aquatic life occupying upper trophic levels.

P. Although a new RfD is available in IRIS, the surface water criteria will not be revised until the National Primary Drinking Water Regulations: Stage 2 Disinfectants and Disinfection Byproducts Rule (Stage 2 DBPR) is completed, since public comment on the relative source contribution (RSC) for chloroform is anticipated.

Q. This recommended water quality criterion is expressed as µg free cyanide (as CN)/L.

R. This value for Selenium was announced (61FR58444-58449, November 14, 1996) as a proposed GLI 303(c) aquatic life criterion. EPA is currently working on this criterion and so this value might change substantially in the near future.

S. This recommended water quality criterion refers to the inorganic form only.

U. The organoleptic effect criterion is more stringent than the value for priority toxic pollutants. Also see Part 6.

V. This value was derived from data for heptachlor and the criteria document provides insufficient data to estimate the relative toxicities of heptachlor and heptachlor epoxide.

W. Although EPA has not published a final criteria document for this compound, it is EPA's understanding that sufficient data exist to allow calculation of aquatic criteria. It is anticipated that industry intends to publish in the peer reviewed literature draft aquatic life criteria generated in accordance with EPA Guidelines. EPA will review such criteria for possible issuance as national WQC.

X. There is a full set of aquatic life toxicity data that show that BEHP is not toxic to aquatic organisms at or below its solubility limit.

Y. This value was derived from data for endosulfan and is most appropriately applied to the sum of alpha- endosulfan and beta-endosulfan.

Z. A more stringent MCL has been issued. Also see part 6 below.

aa This criterion is based on a 304(a) aquatic life criterion issued in 1980 or 1986, and in one of the following documents: Aldrin/Dieldrin (EPA 440/5-80-019), Chlordane (EPA 440/5-80-027), DDT (EPA 440/5-80-038), Endrin (EPA 440/5-80-047), Heptachlor (EPA 440/5-80-052), Polychlorinated Biphenyls (EPA 440/5-80-019), Toxaphene (EPA 440/5-86-038). The CCC is currently based on the Final Residual Value (FRV) procedure. Since the publication of the Great Lakes Aquatic Criteria Guidelines in 1995 (60FR15393-15399, March 23, 1995), the Agency no longer uses the FRV procedure for deriving CCCs for new or revised 304(a) aquatic life criteria. Therefore, the Agency anticipates that future revisions of this CCC will not be based on the FRV procedure.

bb This water quality criterion is based on a 304(a) aquatic life criterion that was derived using the 1985 Guidelines (Guidelines for Deriving Numerical NationalWater Quality Criteria for the Protection of Aquatic Organisms and Their Uses, PB85-227049, January 1985) and was issued in one of the following criteria documents: Arsenic (EPA 440/5-84-033), Chromium (EPA 440/5-84-029), Copper (EPA 440/5-84-031), Cyanide (EPA 440/5-84-028), Lead (EPA 440/5-84-027), Nickel (EPA 440/5-86-004), Pentachlorophenol (EPA 440/5-86-009), Toxaphene, (EPA 440/5-86-006), Zinc (EPA 440/5-87- 003).

cc When the concentration of dissolved organic copper is elevated, copper is substantially less toxic and use of Water Effect Ratio might be appropriate.

dd The selenium criteria document (EPA 440/5-87-006, September 1987) provides that if selenium is as toxic to saltwater fishes in the field as it is to freshwater fishes in the field, the status of the fish community should be monitored whenever the concentration of selenium exceeds 5.0 µg/L in saltwater because the saltwater CCC does not take into account uptake via the food chain.

ff This recommended water quality criterion was derived in Ambient Water Quality Criteria Saltwater Copper Addendum (Draft, April 14, 1995) and was promulgated in the Interim final National Toxics Rule (60FR22228-222237, May 4, 1995).

gg EPA is actively working on this criterion and so this recommended water quality criterion may change substantially in the near future.

ii This criterion applies to DDT and it metabolites (i.e. the total concentration of DDT and its metabolites should not exceed this value).

jj. This criterion is expressed as total cyanide, even though the IRIS RfD used to derive the criterion is based on free cyanide. The multiple forms of cyanide that are present in ambient water have significant differences in toxicity due to their differing abilities to liberate the CN-moiety. Some complex cyanides require even more extreme condition the refluxing with sulfuric acid to liberate the CN-moiety. Thus these complex cyanides are expected to have little or no 'bioavailability' to humans. If a substantial fraction of the cyanide present in water body is present in a complex form (e.g. Fe4[Fe(CN)6]3), this recommended criterion may be over conservative.

aME As noted in 06-096 CMR 584.4 and CMR 584.5.C, when calculating ambient water quality (human health) criteria for inorganic arsenic, a 10-4 risk level and a state-wide consumption value of 138 grams of organisms per day shall be utilized. In waters subject to a designated use of sustenance fishing as specified under 38 MRS §465-A(1)(D), 38 MRS §467(7)(A)(B)(D) 38 MRS §467(13), 38 MRS §467(15)(C), 38 MRS §467(15)(A)(E)(F) 38 MRS §468(8), 38 MRS §469(7), a fish consumption rate of 200 grams per day shall be used. Other values specific to inorganic arsenic shall include a bioconcentration factor of 26 L/kg, a cancer slope (potency) factor of 1.75 mg/kg/day, and an inorganic factor of 30%.

mm. When calculating acute and chronic permit limits for the Androscoggin River, use a Water Effect Ratio (WER) of 1.3 for acute and 3.0 for chronic for cadmium. Rationale for the WERs is provided in Androscoggin River Water Effect Ratios (Integral Consulting Inc., April 13, 2015). WER is defined as an appropriate measure of the toxicity of a material obtained in on site water divided by the same measure of the toxicity of the same material obtained simultaneously in laboratory dilution water.

When calculating acute permit limits for the St. Croix River, use a Water Effect Ratio (WER) of 1.2 for acute for cadmium. Rationale for the WERs is provided in St. Croix River Water-Effect Ratios (Integral Consulting, Inc., July 2019). WER is defined as an appropriate measure of the toxicity of a material obtained in onsite water divided by the same measure of the toxicity of the same material obtained simultaneously in laboratory dilution water.

nn. When calculating acute and chronic permit limits for the Androscoggin River, use a Water Effect Ratio (WER) of 2.5 for acute and 2.5 for chronic for copper. The final WER for chronic copper was determined to be 3.5, however, 2.5 is used to prevent the chronic criteria from exceeding the acute criteria. Rationale for the WERs is provided in Androscoggin River Water Effect Ratios (Integral Consulting Inc., April 13, 2015). WER is defined as an appropriate measure of the toxicity of a material obtained in on site water divided by the same measure of the toxicity of the same material obtained simultaneously in laboratory dilution water.

When calculating acute permit limits for the St. Croix River, use a Water Effect Ratio (WER) of 3.0 for acute for copper. Rationale for the WERs is provided in St. Croix River Water-Effect Ratios (Integral Consulting, Inc., July 2019). WER is defined as an appropriate measure of the toxicity of a material obtained in onsite water divided by the same measure of the toxicity of the same material obtained simultaneously in laboratory dilution water.

oo. When calculating acute and chronic permit limits for total copper in the Little Androscoggin River from the outfall of the Paris Utility District in Paris, to the confluence of the Little Androscoggin River with the main stem Androscoggin River in Auburn, the ambient water quality criteria (AWQC) for acute exposure must be 10.85 micrograms per liter (µg/L) and the chronic AWQC must be 6.78 µg/L. Rationale for the previously noted AWQCs is based on the Biotic Ligand Model (BLM) that is summarized in the Board of Environmental Protection (BEP) Final Order for the Paris Utility District dated November 20, 2014. As stated in the aforementioned Final Order "The copper BLM calculates metal toxicity to aquatic organisms as a function of simultaneous concentrations of chemical constituents in water that can either compete with copper and render it biologically unavailable, or compete with copper for binding sites at the point of entry into a vulnerable organism."

qq. Human Health Ambient Water Quality Criteria: 2015 Update. EPA 820-F-15-001. It should be noted that EPA used a fish consumption rate of 22 g/day to calculate their 2015 values, however the criteria listed here are calculated using a fish consumption rate of 32.4 g/day, generally, and 200 g/day for waters subject to a designated use of sustenance fishing. It should also be noted that antimony, arsenic, barium, beryllium, cadmium, chromium (III or VI), copper, manganese, nickel, nitrates, nitrosamines, N-nitrosodibutylamine, N-nitrosodiethylamine, N-nitrosodipyrrolidine, N-nitrosodimethylamine, N-nitrosodi-n-propylamine, N-nitrosodiphenylamine, polychlorinated biphenyls (PCBs), selenium, thallium, zinc, or 2,3,7,8-TCDD (dioxin) were not included in the 2015 EPA update due to ongoing research.

rr. When calculating acute and chronic permit limits for the St. Croix River, use a Water Effect Ratio (WER) of 3.0 for acute and 4.8 for chronic for lead. Rationale for the WERs is provided in St. Croix River Water-Effect Ratios (Integral Consulting, Inc., July 2019). WER is defined as an appropriate measure of the toxicity of a material obtained in onsite water divided by the same measure of the toxicity of the same material obtained simultaneously in laboratory dilution water.

ss. When calculating acute permit limits for the St. Croix River, use a Water Effect Ratio (WER) of 2.0 for acute for zinc. Rationale for the WERs is provided in St. Croix River Water-Effect Ratios (Integral Consulting, Inc., July 2019). WER is defined as an appropriate measure of the toxicity of a material obtained in onsite water divided by the same measure of the toxicity of the same material obtained simultaneously in laboratory dilution water.

2. Table II. Criteria for Non-Priority Pollutants. See also the footnotes following this table.

Footnotes to Table II:

A This human health criterion is the same as originally published in the Red Book (EPA 440/9-76-023, July 1976) which predates the 1980 methodology and did not utilize the fish ingestion BCF approach. This same criterion value is now published in the Gold Book (Quality Criteria for Water: 1986. EPA 440/5-86-001).

B The organoleptic effect criterion is more stringent than the value presented in the non priority pollutant table.

C A more stringent Maximum Contaminant Level (MCL) has been issued by EPA under the Save Drinking Water Act. Refer to drinking water regulations 40CFR 141 or Safe Drinking Water Hotline (1-800-426-4791) for values. Also see part 6 below.

D Total Ammonia Nitrogen Aquatic life criteria are pH, temperature and/or salinity dependent. See part 7(C) for fresh water and reference document for marine waters. The values presented in the table are based on pH of 7.0 and temperature of 25°C in fresh waters; and pH of 8.0, temperature of 20°C and salinity of 30 parts per thousand in marine waters.

F The derivation of this value is presented in the Red Book (EPA 440/9-76-023, July, 1976).

G This value is based on a 304(a) aquatic life criterion that was derived using the 1985 Guidelines (Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Organisms and Their Uses, PB85-227049, January 1985) and was issued in one of the following criteria documents: Aluminum (EPA 440/5-86-008); Chloride (EPA 440/5-88-001); Chloropyrifos (EPA 440/5-86-005).

J This value is based on a 304(a)aquatic life criterion that was issued in the 1995 Updates: Water Quality Criteria Documents for the Protection of Aquatic Life in Ambient Water (EPA-820-B-96-001). This value was derived using the GLI Guidelines (60FR15393-15399, March 23, 1995; 40CFR 132 Appendix A); the differences between the 1985 Guidelines and the GLI Guidelines are explained on page iv of the 1995 Updates. No decision concerning this criterion was affected by any considerations that are specific to the Great Lakes.

L There are three major reasons why the use of Water-Effect Ratios might be appropriate. (1) The value of 87 µg/l is based on a toxicity test with the striped bass in water with pH= 6.5-6.6 and hardness <10 mg/L. Data in "Aluminum Water-Effect Ratio for the 3M Plant Effluent Discharge, Middleway, West Virginia" (May 1994) indicate that aluminum is substantially less toxic at higher pH and hardness, but the effects of pH and hardness are not well quantified at this time. (2) In tests with the brook trout at low pH and hardness, effects increased with increasing concentrations of total aluminum even though the concentration of dissolved aluminum was constant, indicating that total recoverable is a more appropriate measurement than dissolved, at least when particulate aluminum is primarily aluminum hydroxide particles. In surface waters, however, the total recoverable procedure might measure aluminum associated with clay particles, which might be less toxic than aluminum associated with aluminum hydroxide. (3) EPA is aware of field data indicating that many high quality waters in the U.S. contain more than 87 µg aluminum/L, when either total recoverable or dissolved is measured.

N This value was announced (62FR42554, August 7, 1997) as a proposed 304(a) aquatic life criterion. Although EPA has not responded to public comment, EPA has published this as a 304(a) criterion as guidance for States and Tribes to consider when adopting water quality criteria.

O When calculating acute and chronic permit limits for the Androscoggin River, use a Water Effect Ratio (WER) of 1.3 for acute and 3.7 for chronic for aluminum. Rationale for the WERs is provided in Androscoggin River Water Effect Ratios (Integral Consulting Inc., April 13, 2015).

P When calculating acute and chronic permit limits for the St. Croix River, use a Water Effect Ratio (WER) of 6.1 for aluminum. Rationale for the WER is provided in Aluminum Water-Effect Ration for Georgia-Pacific Corporation Woodland, Maine Pulp & Paper Operations Discharge and St. Croix River prepared by AScI Corporation/AScI-Duluth dated November 1996, and summarized in the letter from William R. Beckwith of EPA Region 1 to Barry Mower, DEP, dated March 2, 1998.

ADDITIONAL NOTES

3. Criteria Maximum Concentration and Criterion Continuous Concentration

The Criteria Maximum Concentration (CMC) is an estimate of the highest concentration of a material in surface water to which an aquatic community can be exposed briefly without resulting in an unacceptable effect. The Criterion Continuous Concentration (CCC) is an estimate of the highest concentration of a material in surface water to which an aquatic community can be exposed indefinitely without resulting in an unacceptable effect. The CMC and CCC are just two of the six parts of an aquatic life criterion; the other four parts are the acute averaging period, chronic averaging period, acute frequency of allowed exceedence, and chronic frequency of allowed exceedence. Because 304(a) aquatic life criteria are national guidance, they are intended to be protective of the vast majority of the aquatic communities in the United States.

4. Criteria Recommendations for Priority Pollutants, Non Priority Pollutants

This compilation lists all priority toxic pollutants and some non priority toxic pollutants, and both human health effect and aquatic organism effect criteria issued pursuant to CWA §304(a). Blank spaces indicate that EPA has no CWA §304(a) criteria recommendations. For a number of non-priority toxic pollutants not listed, CWA §304(a) "water + organism" human health criteria are not available, but EPA has published MCLs under the SDWA that may be used in establishing water quality standards to protect water supply designated uses. Because of variations in chemical nomenclature systems, this listing of toxic pollutants does not duplicate the listing in Appendix A of 40 CFR Part 423. Also listed are theChemical Abstracts Service CAS registry numbers, which provide a unique identification for each chemical.

5. Water Quality Criteria published pursuant to Section 304(a) or Section 303(c) of the CWA

Many of the values in the compilation were published in the California Toxics Rule. Although such values were published pursuant to Section 303(c) of the CWA, they represent the EPA's most recent calculation of water quality criteria and are thus the Agency's 304(a) criteria.

6. Maximum Contaminant Levels and Organoleptic Effects

The compilation includes footnotes for pollutants with Maximum Contaminant Levels (MCLs) more stringent than the recommended water quality criteria in the compilation. MCLs for these pollutants are not included in the compilation, but can be found in the appropriate drinking water regulations (10-144 CMR Chapter 231, 40 CFR 141.11-16 and 40 CFR 141.60-63). In addition to toxic effects, some pollutants impart organoleptic effects (e.g., taste and odor) that may impair uses of the waters of the State by making water and edible aquatic life unpalatable but not toxic to humans. Pollutants with organoleptic effect criteria more stringent than the criteria based on toxicity (e.g., included in both the priority and non-priority pollutant tables) are footnoted as such. For both MCL and organoleptic effects, the Department will consider all available information regarding such characteristics in regulating the discharge of pollutant to ensure the uses of the waters of the State are protected in all respects.

7. Specific Chemical Calculations

A. Selenium Aquatic Life

This compilation contains aquatic life criteria for selenium that are the same as those published in the proposed CTR. In the CTR, EPA proposed an acute criterion for selenium based on the criterion proposed for selenium in the Water Quality Guidance for the Great Lakes System (61 FR 58444). The GLI and CTR proposals take into account data showing that selenium's two prevalent oxidation states in water, selenite and selenate, present differing potentials for aquatic toxicity, as well as new data indicating that various forms of selenium are additive. The new approach produces a different selenium acute criterion concentration, or CMC, depending upon the relative proportions of selenite, selenate, and other forms of selenium that are present. EPA is currently undertaking a reassessment of selenium, and expects the 304(a) criteria for selenium will be revised based on the final reassessment (63FR26186). However, until such time as revised water quality criteria for selenium are published by the Agency, the recommended water quality criteria in this compilation are EPA's current 304(a) criteria.

B. Parameters for Calculating Freshwater Metals Criteria That Are Hardness-Dependent

Hardness-dependant metals' criteria, as total metal, may be calculated from the following.

CMC = exp{mA [ln(hardness)] + bA}

CCC = exp{mC [ln(hardness)] + bC}

A conversion factor for freshwater cadmium criteria is then applied to the above stated calculation for CCC and CMC as stated in EPA's Aquatic Life Ambient Water Quality Criteria for Cadmium (EPA-820-R-16-002) dated March 2016. Freshwater acute and chronic conversion factors for cadmium are 1.011 and 0.976, respectively.

C. Calculation of Freshwater Ammonia Criterion

Freshwater Ammonia criterion is derived from Aquatic Life Ambient Water Quality Criteria for Ammonia-Freshwater (EPA 822-R-18-002) dated April 2013. Criteria frequency may not be exceeded more than once in three years on average. Chronic criteria (30-day rolling average), may not exceed 2.5 times the criterion continuous concentration as a 4-day average within a 30-day period.