2092 Amendments to Comprehensive Plan, Water Code of the Delaware River Basin and Administrative Manual--Part III Water Quality Regulations
DELAWARE RIVER BASIN COMMISSION [25 PA. CODE CH. 901] Amendments to Comprehensive Plan, Water Code of the Delaware River Basin and Administrative Manual--Part III Water Quality Regulations [26 Pa.B. 5973] Agency: Delaware River Basin Commission.
Action: Final rule.
Summary: At its October 23, 1996 business meeting, the Delaware River Basin Commission amended its Comprehensive Plan, Water Code and Water Quality Regulations concerning water quality criteria for toxic pollutants, and policies and procedures to establish wasteload allocations and effluent limitations for point source discharges to Zones 2 through 5 (Trenton, New Jersey to the Delaware Bay) of the tidal Delaware River.
Effective Date: January 1, 1997.
Addresses: Copies of the Commission's Water Code of the Delaware River Basin, Administrative Manual--Part III Water Quality Regulations, the full text of the amendments and Response Document--September 5, 1996 Public Hearing are available from the Delaware River Basin Commission, P.O. Box 7360, West Trenton, New Jersey 08628.
For Further Information Contact: Susan M. Weisman, Commission Secretary, Delaware River Basin Commission: Telephone (609) 883-9500 ext. 203.
Supplementary Information: On October 5, 11 and 13, 1995, the Commission held public hearings on proposed amendments to its water quality regulations as noticed in the Pennsylvania Bulletin issues of August 26 and September 23, 1995. As a result of comments received on that proposal and discussions with the Commission's Water Quality and Toxics Advisory Committees, the Commission modified its initial proposal. The proposed regulations, as modified, were the subject of a public hearing on September 5, 1996 as noticed in the Pennsylvania Bulletin issue of July 27, 1996.
Specifically, water quality criteria for selected toxic pollutants are incorporated in the Comprehensive Plan and Article 3 of the Water Code and Water Quality Regulations as stream quality objectives. Article 4 of the Water Quality Regulations has also been amended to include policies and procedures to be used to establish wasteload allocations for those discharges containing pollutants which exceed the stream quality objectives and impact the designated uses of the river.
Adoption of these amendments provides a mechanism for identifying toxic pollutants which impair aquatic life and human health, and developing uniform and equitable wasteload allocations for those NPDES discharges to the tidal Delaware River which contribute to their impairment. The permitting authorities of the Basin states will utilize allocations developed by the Commission to establish effluent limitations for NPDES permittees in their jurisdiction, as appropriate.
Based upon testimony received since the initial proposal and considerable deliberation, the Commission has amended its Comprehensive Plan, Water Code of the Delaware River Basin and Administrative Manual--Part III Water Quality Regulations.
1. Article 3 of the Administrative Manual--Part III Water Quality Regulations, the Comprehensive Plan and Article 3 of the Water Code of the Delaware River Basin are hereby amended as follows:
a. Subsections 3.10.3C. and D. are added to read as follows:
C. Aquatic Life Objectives for Toxic Pollutants. It is the policy of the Commission to designate numerical stream quality objectives for the protection of aquatic life for the Delaware River Estuary (Zones 2 through 5) which correspond to the designated uses of each zone. Aquatic life objectives for the protection from both acute and chronic effects are herein established on a pollutant-specific basis for:
pollutants listed as toxic under Section 307(a)(1) of the Clean Water Act for which the U. S. Environmental Protection Agency (EPA) has published final criteria,
other chemicals for which EPA has published final criteria under Section 304(a) of the Act, and
pollutants and other chemicals in combinations.
Other toxic substances for which any of the three Estuary states have adopted criteria or standards may also be considered for the development of stream quality objectives.
1. For the purpose of determining compliance with stream quality objectives for the protection of aquatic life, the duration of exposure of aquatic organisms shall be 1 hour for acute objectives and 4 days for chronic objectives.
2. Stream quality objectives for cadmium, chromium, copper, lead, nickel, silver and zinc shall be expressed as the dissolved form of the metal. Adjustment factors established by the Commission based upon the best available scientific information shall be used to convert total recoverable criteria published by the U.S. Environmental Protection Agency to dissolved stream quality objectives. In the absence of data to develop a factor for any of the metals, an adjustment factor of 1.0 shall be utilized. Stream quality objectives for other metals shall be expressed as the concentration of the total recoverable form of the metal.
D. Human Health Objectives for Toxic Pollutants. It is the policy of the Commission to designate numerical stream quality objectives for the protection of human health for the Delaware River Estuary (Zones 2 through 5) which correspond to the designated uses of each zone. Stream quality objectives for protection from both carcinogenic and systemic effects are herein established on a pollutant-specific basis for:
pollutants listed as toxic under Section 307(a)(1) and other toxic pollutants, and
other chemicals for which EPA has published final criteria under Section 304(a) of the Act.
Other toxic substances for which any of the three Estuary states have adopted criteria or standards may also be considered for the development of stream quality objectives.
1. An objective to protect against carcinogenic effects shall only be established if the pollutant is classified A, B or C under the EPA classification system for carcinogens, and if a cancer potency factor (CPF) exists in IRIS.
2. An objective to protect against systemic effects shall only be established for a pollutant if a reference dose (RfD) exists in IRIS. An additional safety factor of 10 shall be utilized in establishing the stream quality objectives to protect against systemic effects for pollutants classified as carcinogens if a CPF is not available in IRIS.
3. In the absence of toxicological data for an RfD or CPF in IRIS, data published in the 1980 U.S. EPA water quality criteria documents will be considered.
4. In establishing stream quality objectives for carcinogens, the level of risk is established at 10-6 or one additional cancer in every 1,000,000 humans exposed for a lifetime (70 years).
5. For the purpose of determining compliance with human health stream quality objectives, the duration of exposure shall be 70 years for carcinogens and 30 days for systemic toxicants.
6. A rate of ingestion of water of 2.0 liters per day is assumed in calculating objectives for river zones where the designated uses include public water supplies after reasonable treatment. A rate of ingestion of fish of 6.5 grams per day (equivalent to consuming a 1/2 pound portion every 35 days) is assumed in calculating freshwater stream quality objectives for human health. A rate of ingestion of fish of 37 grams per day (equivalent to consuming a 1/2 pound portion every 6 days) is assumed in calculating marine stream quality objectives for human health.
7. Maximum Contaminant Levels (MCLs) shall be applied as stream quality objectives in Zones 2 and 3 which are designated for use as public water supplies for those toxic pollutants where the MCL value is more stringent than the calculated human health objectives for carcinogens or systemic toxicants.
8. Numerical criteria for toxic pollutants to protect the taste and odor of ingested water and fish shall be applied as stream quality objectives in the Estuary if these criteria are more stringent than the calculated human health objectives for carcinogens or systemic toxicants.
b. Subsection 3.10.5D. is revised to read as follows:
D. Streamflow. Numerical stream quality objectives are based on a minimum consecutive 7-day flow with a 10-year recurrence interval unless otherwise specified.
c. Subsection 3.10.5E. is added to read as follows:
E. Requests for Modification of Stream Quality Objectives. The Commission will consider requests to modify the stream quality objectives for toxic pollutants based upon site-specific factors. Such requests shall provide a demonstration of the site-specific differences in the physical, chemical or biological characteristics of the area in question, through the submission of substantial scientific data and analysis. The demonstration shall also include the proposed alternate stream quality objectives. The methodology and form of the demonstration shall be approved by the Commission.
d. Subsections 3.10.6H. through P. are added to read as follows:
H. IRIS. The Integrated Risk Information System established and maintained by the U.S. Environmental Protection Agency. An electronic data base containing information on the toxicity and carcinogenicity of individual substances which can be accessed by regulatory agencies and the public.
I. Carcinogen. A substance for which there is no level of exposure that does not pose a small, finite probability of inducing benign or malignant tumors.
J. Systemic Toxicant. A substance having a threshold exposure which must be exceeded before deleterious effects (other than cancer) are observed in organ systems.
K. Acute Effects. Effects (including but not limited to lethality) due to exposure to a toxicant over a short time period.
L. Chronic Effects. Effects (including but not limited to reduced reproduction, reduced growth and lethality) due to exposure to a toxicant over a relatively long period of time relative to the life span of the exposed organism.
M. Cancer Potency Factor (CPF). The slope of the dose response curve in the low dose region expressed as the risk per milligram of a toxic substance per kilogram of body weight per day (mg/KG/day)u1.
N. Reference Dose (RfD). The daily exposure to a substance that is likely to be without an appreciable risk of deleterious effects during a lifetime expressed as milligram of the substance per kilogram of body weight per day (mg/KG/day).
O. Maximum Contaminant Level (MCL). The maximum permissible level of a contaminant in water which is delivered to any user of a public water system.
P. Stream Quality Objectives. Numeric values for specific pollutants and narrative descriptions of the quality of a waterbody that will assure that the designated uses of the waterbody, including the protection of aquatic life and human health, are achieved.
e. Subsection 3.30.2C.14. is added to read as follows:
14. Toxic Pollutants.
a. Applicable MCLs and criteria to protect the taste and odor of ingested water and fish are presented in Tables 3 and 4.
b. Applicable freshwater stream quality objectives for the protection of aquatic life are presented in Table 5.
c. Applicable freshwater stream quality objectives for the protection of human health are presented in Tables 6 and 7.
f. Subsection 3.30.3C.15. is added to read as follows:
15. Toxic Pollutants.
a. Applicable MCLs and criteria to protect the taste and odor of ingested water and fish are presented in Tables 3 and 4.
b. Applicable freshwater stream quality objectives for the protection of aquatic life are presented in Table 5.
c. Applicable freshwater stream quality objectives for the protection of human health are presented in Tables 6 and 7.
g. Subsection 3.30.4C.12. is added to read as follows:
12. Toxic Pollutants.
a. Applicable criteria to protect the taste and odor of ingested water and fish are presented in Table 4.
b. Applicable freshwater stream quality objectives for the protection of aquatic life are presented in Table 5.
c. Applicable freshwater stream quality objectives for the protection of human health are presented in Tables 6 and 7.
h. Subsection 3.30.5C.11. is added to read as follows:
11. Toxic Pollutants. Freshwater stream quality objectives apply in areas upstream of the Delaware Memorial Bridges (River Mile 68.75), and the more stringent of the freshwater or marine stream quality objectives apply in areas below RM 68.75.
a. Applicable criteria to protect the taste and odor of ingested water and fish are presented in Table 4.
b. Applicable freshwater and marine stream quality objectives to protect aquatic life are presented in Table 5.
c. Applicable freshwater and marine stream quality objectives to protect human health are presented in Tables 6 and 7.
Table 3: MAXIMUM CONTAMINANT LEVELS TO BE APPLIED AS HUMAN HEALTH STREAM QUALITY OBJECTIVES IN ZONES 2 AND 3 OF THE DELAWARE RIVER ESTUARY. Maximum Contaminant Parameter Level (ug/l) Antimony 6 Arsenic 50 Barium 2.0 mg/l Cadmium 5 Chromium (total) 100 Nickel 100 Selenium 50 1,2-trans-Dichloroethene 100 1,2-Dichloropropane 5 Ethylbenzene 700 gamma-BHC (Lindane) 0.2 1,2,4-Trichlorobenzene 70 Total Trihalomethanes 100 Table 4: CRITERIA TO PROTECT THE TASTE AND ODOR OF INGESTED WATER AND FISH TO BE APPLIED AS HUMAN HEALTH STREAM QUALITY OBJECTIVES IN ALL ZONES OF THE DELAWARE RIVER ESTUARY. STREAM QUALITY Parameter OBJECTIVE (ug/l) Phenol 300 2-Chlorophenol 0.1 2,4-Dichlorophenol 0.3 2,4-Dimethylphenol 400 4-Chloro-3-methylphenol 3.0 mg/l Pentachlorophenol 30 Acenaphthene 20 Chlorobenzene 20 Hexachlorocyclopentadiene 1.0 Nitrobenzene 30
Table 5: STREAM QUALITY OBJECTIVES FOR TOXIC POLLUTANTS FOR THE PROTECTION OF AQUATIC LIFE IN THE DELAWARE RIVER ESTUARY.Freshwater Objectives (ug/l) Marine Objectives (ug/l) Parameter Acute Chronic Acute Chronic Metals (Values indicated are total recoverable;
see Section 3.10.3.C.2. for form of metal)
Aluminum 750 87 -- -- Arsenic (trivalent) 360 190 69 36 Cadmium e(1.128*LN(Hardness)-3.828) e(0.7852*LN(Hardness)-3.49) 43 9.3 Chromium (trivalent) e(0.8190*LN(Hardness)+3.688) e(0.8190*LN(Hardness)+1.561) -- -- Chromium (hexavalent) 16 11 1,100 50 Copper e(0.9422*LN(Hardness)-1.464) e(0.8545*LN(Hardness)-1.465) 5.3 3.4 Cyanide (total) 22 5.2 1.0 -- Lead 48 16 220 8.5 Mercury 2.4 0.012 2.1 0.025 Nickel e(0.846*LN(Hardness)+3.3612) e(0.846*LN(Hardness)+1.1645) 75 8.3 Selenium 20 5.0 300 71 Silver e(1.72*LN(Hardness)-6.52) -- 2.3 -- Zinc e(0.8473*LN(Hardness)+0.8604) e(0.8473*LN(Hardness)+0.7614) 95 86 Pesticides/PCBs
Aldrin 1.5 -- 0.65 -- gamma-BHC (Lindane) 1.0 0.08 0.08 -- Chlordane 1.2 0.0043 0.045 0.004 Chlorpyrifos (Dursban) 0.083 0.041 0.011 0.0056 DDT and metabolites
(DDE & DDD)0.55 0.001 0.065 0.001 Dieldrin 1.25 0.0019 0.355 0.0019 Endosulfan 0.11 0.056 0.017 0.0087 Endrin 0.09 0.0023 0.019 0.0023 Heptachlor 0.26 0.0038 0.027 0.0036 PCBs (Total) 1.0 0.014 5.0 0.03 Parathion 0.065 0.013 -- -- Toxaphene 0.73 0.0002 0.21 0.0002 Acid Extractable Organics Pentachlorophenol e(1.005*pH-4.83) e(1.005*pH-5.29) 13 7.9 Indicator Parameters
Whole Effluent Toxicity 0.3 Toxic Unitsacute 1.0 Toxic Unitschronic 0.3 TUa 1.0 TUc
Table 6: STREAM QUALITY OBJECTIVES FOR CARCINOGENS FOR THE DELAWARE RIVER ESTUARY. MARINE OBJECTIVES FRESHWATER OBJECTIVES (µg/l) (µg/l) FISH & WATER FISH INGESTION FISH INGESTION PARAMETER EPA CLASS. INGESTION ONLY ONLY Beryllium B2 0.00767 0.132 0.0232 Aldrin B2 0.00189 0.0226 0.00397 alpha-BHC B2 0.00391 0.0132 0.00231 Chlordane B2 0.000575 0.000588 0.000104 DDT B2 0.000588 0.000591 0.000104 DDE B2 0.00554 0.00585 0.00103 DDD B2 0.00423 0.00436 0.000765 Dieldrin B2 0.000135 0.000144 0.0000253 Heptachlor B2 0.000208 0.000214 0.0000375 Heptachlor epoxide B2 0.000198 0.000208 0.0000366 PCBs (Total) B2 0.0000444 0.0000448 0.0000079 Toxaphene B2 0.000730 0.000747 0.000131 Acrylonitrile B1 0.0591 0.665 0.117 Benzene A 1.19 71.3 12.5 Bromoform B2 4.31 164.0 28.9 Bromodichloromethane B2 0.559 55.7 9.78 Carbon tetrachloride B2 0.254 4.42 0.776 Chlorodibromomethane C 0.411 27.8 4.88 Chloroform B2 5.67 471.0 82.7 1,2-Dichloroethane B2 0.383 98.6 17.3 1,1-Dichloroethene C 0.0573 3.20 0.562 1,3-Dichloropropene B2 87.0 14.1 2.48 Methylene chloride B2 4.65 1,580 277 Tetrachloroethene B2 0.80 8.85 1.55 1,1,1,2-Tetrachloroethane C 1.29 29.3 5.15 1,1,2,2-Tetrachloroethane C 0.172 10.8 1.89 1,1,2-Trichloroethane C 0.605 41.6 7.31 Trichloroethene B2 2.70 80.7 14.2 Vinyl chloride A 2.00 525.0 92.9 Benzidine A 0.000118 0.000535 0.000094 3,3-Dichlorobenzidine B2 0.0386 0.0767 0.0135 PAHs Benz[a]anthracene B2 0.00171 0.00177 0.00031 Benzo[b]fluoranthene B2 0.000455 0.000460 0.000081 Benzo[k]fluoranthene B2 0.000280 0.000282 0.000049 Benzo[a]pyrene B2 0.0000644 0.0000653 0.0000115 Chrysene B2 0.0214 0.0224 0.00394 Dibenz[a,h]anthracene B2 0.0000552 0.0000559 0.0000098 Indeno[1,2,3-cd]pyrene B2 0.0000576 0.0000576 0.0000101 Bis(2-chloroethyl)ether B2 0.0311 1.42 0.249 Bis(2-ethylhexyl)phthalate B2 1.76 5.92 1.04 Dinitrotoluene mixture (2,4 & 2,6) B2 17.3 1420 249 1,2-Diphenylhydrazine B2 0.0405 0.541 0.095 Hexachlorobenzene B2 0.000748 0.000775 0.000136 Hexachlorobutadiene C 0.445 49.7 8.72 Hexachloroethane C 1.95 8.85 1.56 Isophorone C 36.3 2590 455 N-Nitrosodi-N-methylamine B2 0.000686 8.12 1.43 N-Nitrosodi-N-phenylamine B2 4.95 16.2 2.84 N-Nitrosodi-N-propylamine B2 0.00498 1.51 0.265 Pentachlorophenol B2 0.282 8.16 1.43 2,4,6-Trichlorophenol B2 2.14 6.53 1.15 Dioxin (2,3,7,8-TCDD) -- 1.3 x 10-8 1.4 x 10-8 2.4 x 10-9
Table 7: STREAM QUALITY OBJECTIVES FOR SYSTEMIC TOXICANTS FOR THE DELAWARE RIVER ESTUARY. MARINE OBJECTIVES FRESHWATER OBJECTIVES (ug/l) (ug/l) FISH & WATER FISH INGESTION FISH INGESTION PARAMETER EPA CLASS. INGESTION ONLY ONLY Antimony 14.0 4,310 757 Arsenic A 9.19 73.4 12.9 Beryllium B2 165 2,830 498 Cadmium 14.5 84.1 14.8 Chromium (Trivalent) 33,000 673,000 118,000 Hexavalent chromium A 166 3,370 591 Mercury D 0.144 0.144 0.144 Nickel 607 4,580 805 Selenium D 100 2,020 355 Silver D 175 108,000 18,900 Thallium 1.70 6.20 1.10 Zinc 9,110 68,700 12,100 Aldrin B2 0.96 11.5 2.03 gamma-BHC (Lindane) 7.38 24.9 4.37 Chlordane B2 0.0448 0.0458 0.00805 DDT B2 0.100 0.100 0.0176 Dieldrin B2 0.108 0.115 0.020 Endosulfan 111 239 42.0 Endrin D 0.755 0.814 0.143 Heptachlor B2 0.337 0.344 0.060 Heptachlor epoxide B2 0.0234 0.0246 0.00433 Total PCBs B2 0.00839 0.00849 0.00149 Acrolein 320 780 137 Ethylbenzene 3,120 28,700 5,050 Bromoform B2 682 25,900 4,560 Bromodichloromethane B2 693 69,000 12,100 Dibromochloromethane C 690 46,600 8,190 Carbon tetrachloride B2 23.1 402 70.6 Chloroform B2 346 28,700 5,050 Chlorobenzene D 677 20,900 3,670 1,1-Dichloroethene C 309 17,300 3,040 1,2-trans-Dichloroethene 696 136,000 23,900 1,3-Dichloropropene B2 10.4 1,690 297 Methyl bromide 49.0 N/A N/A Methylene chloride B2 2,090 710,000 125,000 1,1,2-Trichloroethane C 138 9,490 1,670 Tetrachloroethene 318 3,520 618 1,1,1,2-Tetrachloroethane C 1,000 22,400 3,940 Toluene 6,760 201,000 35,400 Acenaphthene 1,180 2,670 469 Anthracene D 4,110 6,760 1,190 Benzidine A 81.8 369 64.9 Bis(2-chloroisopropyl)ether 1,390 174,000 30,600 Bis(2-ethylhexyl)phthalate B2 492 1,660 291 Butylbenzl phthalate C 298 520 91.4 Diethyl phthalate D 22,600 118,000 20,700 Dimethyl phthalate D 313,000 2,990,000 526,000 Dibutyl phthalate D 2,710 12,100 2,130 1,2-Dichlorobenzene D 2,670 17,400 3,060 1,3-Dichlorobenzene D 414 3,510 617 1,4-Dichlorobenzene 419 3,870 677 2,4-Dinitrotoluene 69.2 5670 996 Fluoranthene 296 375 65.8 Fluorene D 730 1,530 268 Hexachlorobenzene B2 0.958 0.991 0.174 Hexachlorobutadiene C 69.4 7,750 1,360 Hexachlorocyclopentadiene 242 17,400 3,050 Hexachloroethane C 27.3 124 21.7 Isophorone C 6,900 492,000 86,400 Nitrobenzene D 17.3 1,860 327 Pyrene D 228 291 51.1 1,2,4-Trichlorobenzene D 255 945 166 2-Chlorophenol 122 402 70.6 2,4-Dichlorophenol 92.7 794 139 2,4-Dimethylphenol 536 2,300 403 2,4-Dinitrophenol 70 14,300 2,500 Pentachlorophenol B2 1,010 29,400 5,160 Phenol 20,900 4,620,000 811,000
2. Article 4 of the Administrative Manual--Part III Water Quality Regulations is hereby amended as follows:
a. Subsection 4.20.4B. is revised to read as follows:
B. so that the assimilation of such waste by the interstate waters will not result in a violation of such water quality criteria.
1. For the purposes of establishing wasteload allocations for toxic pollutants for the Delaware River Estuary, the lower of the 95th percentile of the available data at the appropriate criteria duration, or the water quality criterion at or above the head of the tide shall be used to establish boundary conditions.
b. Subsection 4.20.5 is added to read as follows:
4.20.5 Application of Criteria for Toxic Pollutants.
A. Delaware River Estuary.
1. In establishing wasteload allocations and other effluent requirements, exceedances of stream quality objectives for the protection of aquatic life from acute effects may be permitted in small areas near outfall structures, provided that all of the following requirements are met.
a. As a guideline, the dimensions of the area where objectives are exceeded should be limited to the more stringent of the following restrictions:
1). a distance of 50 times the discharge length scale in any direction from the outfall structure, or
2). a distance of 5 times the local water depth in any direction from the outfall structure.
b. Stream quality objectives shall not be exceeded in areas designated as critical habitat for fish and benthic organisms.
c. Stream quality objectives shall not be exceeded where effluent flows over exposed benthic habitat prior to mixing with the receiving waters.
d. A zone of passage for free-swimming and drifting organisms equal to 50% of the surface width of the river at the location of the discharge shall be provided.
e. The total surface area of the Delaware River Estuary where stream quality objectives for the protection of aquatic life from acute effects are exceeded shall be limited to:
1). 5% of the total surface area of Zones 2, 3 and 4, and
2). 5% of the total surface area of Zone 5.
f. Upon the request of one or more dischargers, the Executive Director may consider requests for alternatives to the requirements of subsections a. through e. of Section 4.20.5.A.1. Such requests shall provide a demonstration that the alternative requirement requested will not adversely impact free-swimming, drifting and benthic organisms. The demonstration(s) shall provide a sound rationale, and be supported by substantial scientific data and analysis. The methodology and form of the demonstration shall be approved by the Executive Director. The Executive Director may reject any requests which are not substantive. The Commission may establish alternative areas where acute stream quality objectives may be exceeded based upon the evaluation of submitted demonstrations.
g. The Executive Director may consider requests to conduct studies to confirm the mixing characteristics and the predicted dilution isopleths of a discharge. Such requests shall provide a demonstration based upon sound scientific and technical rationale, and be supported by substantial data and analysis. The methodology and form of the demonstration shall be approved by the Executive Director. The Executive Director may reject any requests which are not substantive. The Commission may establish alternative dilution factors based upon the evaluation of submitted demonstrations.
2. For those stream quality objectives whose numerical value is related to hardness, a median hardness value of 74 mg/l as CaCO3 shall be used to represent the hardness of the receiving water for the purposes of determining the numerical value of those objectives. This median hardness value shall be used to establish the aquatic life objective for protection from chronic effects; and in conjunction with the site-specific median hardness value of the effluent and the dilution factor, the aquatic life objective for protection from acute effects.
3. For those stream quality objectives whose numerical value is related to pH, a median pH value of 7.1 shall be used to represent the pH of the receiving water for the purposes of determining the numerical value of those objectives. This median pH value shall be used to establish the aquatic life objective for protection from chronic effects; and in conjunction with the site-specific median pH value of the effluent and the dilution factor, the aquatic life objective for protection from acute effects.
4. Assumptions for Estuarine Mixing. Complete vertical and lateral mixing shall be assumed in the Estuary in applying chronic aquatic life and human health stream quality objectives under design conditions. Site-specific data which does not support this assumption will be considered by the Executive Director in establishing allocations to discharges.
5. Deriving Total Recoverable Wasteload Allocations for Metals. Wasteload allocations developed from the dissolved stream quality objectives for seven cationic metals shall be converted into total recoverable wasteload allocations using a translator. The translator shall be determined using procedures specified by the Commission. In the absence of data to develop a translator for any of the metals, the reciprocal of the conversion factor established under Section 3.10.3C.2. shall be used for the translator.
B. Definitions.
1. Critical Habitat. Specific areas within the tidal Delaware River which are or could be occupied by a species absent the toxic effect of pollutants; and which have those physical, chemical and biological features which are essential to the conservation and maintenance of the Delaware Estuary population. The Commission shall identify and determine critical habitat within the tidal Delaware River. Such determination shall consider the spatial and temporal requirements of the species including critical life stages. Determinations shall be governed by the Commission's Rules of Practice and Procedure relating to review, hearing and decisions of objections thereto.
2. Discharge Length Scale. The square root of the cross-sectional area of any discharge outlet.
c. Subsection 4.30.7A.4.a. is revised to read as follows:
a. The reserve in each zone shall be utilized to accommodate new discharges or major revisions to an allocation, or any reallocation, when appropriate in the judgment of the Commission.
d. Subsection 4.30.7A.5. is revised to read as follows:
5. Reallocations.
a. Carbonaceous Oxygen Demand
1). All allocations shall be subject to review by the Commission and, after such review, the Commission may make such reallocation as it deems necessary.
2). If any factors upon which an individual allocation is based change significantly, application shall be made to the Executive Director for a revised allocation.
3). Whenever the reserve in a zone approaches depletion, or when the full use of the assimilative capacity is approached, or when in the judgment of the Commission, the allocations existing at that time are no longer equitable, the capacity in the zone, minus a reserve, will be reallocated among the waste dischargers in that zone.
b. Toxic Pollutants
1). All allocations shall be subject to review by the Commission and, after such review, the Commission may make such reallocation as it deems necessary.
2). If any factors upon which an individual allocation is based change significantly, application shall be made to the Executive Director for a revised allocation. The Executive Director shall provide notice to interested and affected parties prior to establishing the revised allocation.
3). Allocations shall, as a minimum, be reviewed and, if required, revised every five years, or as directed by the Commission.
e. Subsection 4.30.7A.8. is added to read as follows:
8. Design Effluent Flow. For the purpose of determining the waste assimilative capacity of a stream and the wasteload allocations for discharges of toxic pollutants, the following design effluent flows will be used:
a. For industrial wastewater treatment plant discharges covered by Effluent Limitations Guidelines (ELG) promulgated by the U.S. EPA, the effluent design flow shall be the average daily flow associated with:
1). the month having the highest monthly production rate of the previous twelve months or, if greater,
2). the year having the highest annual production rate of the previous five years.
b. If the discharge from an industrial wastewater treatment plant is not covered by Effluent Limitations Guidelines (ELG) promulgated by the U.S. EPA, is mixed with stormwater or cooling water or production data are not available, the effluent design flow shall be the average daily flow associated with:
1). the month with the highest monthly flow rate of the previous twelve months, or if greater,
2). the year having the highest annual flow rate of the previous five years.
c. For municipal wastewater treatment plant discharges, the effluent design flow shall be the higher of:
1). the average daily flow of the plant for the previous three years including a growth factor based upon a five-year projection, if available, or
2). the capacity of the plant that was used to establish effluent limitations for the NPDES permit expressed as the annual average flow.
f. Subsection 4.30.7B.2. is added to read as follows:
2. Toxic Pollutants. Pursuant to Sections 3.10.4.E. and 4.30.7.A. of these regulations, the Commission shall establish wasteload allocations and other effluent requirements that may be necessary to meet the stream quality objectives for toxic pollutants contained in Section 3.30.
a. Reserve. A reserve allocation of 5% of the Total Maximum Daily Load (TMDL) shall be established as a part of an allocation or reallocation, by increasing the effluent design flow by 5%.
b. Margin of Safety. As part of an allocation or reallocation, a proportion of the Total Maximum Daily Load shall be established as a margin of safety. The proportion established shall reflect the degree of uncertainty in the data and resulting water quality-based controls.
c. Allocation to Discharges.
1). Wasteload allocations shall be established for Phase 1 continuous point source discharges to address acute aquatic life protection, chronic aquatic life protection and both carcinogenic and systemic toxicants.
a). The water quality objective for the establishment of any allocation or reallocation shall be the stream quality objectives contained in Section 3.30. If the background concentration of a toxic pollutant at the appropriate criteria duration exceeds the stream quality objective as a result of loadings from sources not subject to control, then the water quality objective shall be the background concentration of the pollutant.
b). The minimum flows for aquatic life protection and to protect the taste and odor of ingested water and fish are based on a minimum consecutive 7-day flow with a 10-year recurrence interval for all tributaries; and for the Delaware River, a flow of 2500 cfs at Trenton. For the protection of human health, the harmonic mean flow shall be used for carcinogens, and the minimum consecutive 30-day flow with a 5-year recurrence interval shall be used for systemic toxicants.
2). Allocations shall be determined by the Executive Director using the procedure described in Section 4.30.7.B.2.c.4). or alternative procedures that are consistent with the doctrine of equitable apportionment, and achieve the following:
a). assure compliance with applicable stream quality objectives;
b). provide maximum equity among competing discharges; and
c). minimize the overall cost of compliance.
3). The loadings of toxic pollutants identified in Section 4.30.7.B.2.c. shall be allocated among individual Phase 1 continuous point source discharges which meet any of the following criteria:
a). The discharge has an existing permit limit for the parameter,
b). Effluent data indicates the presence of the parameter, or
c). The reasonable potential exists for the parameter to occur in the discharge.
4). Allocations for Phase 1 continuous point source discharges will be based upon the equal marginal percent reduction procedure which has been determined to be consistent with the requirements of Section 4.30.7.B.2.c.2). This procedure requires all dischargers, whether they are part of a multiple discharge wasteload allocation scenario or not, to provide treatment of their wastewater to achieve the applicable water quality standard; and in addition, requires some dischargers to provide additional treatment due to the cumulative impact of all discharges.
a). Alternative wasteload allocation procedures may be considered by the Commission if they provide timely compliance with Section 4.30.7.B.2.c.2). and include the consent of all dischargers affected by the alternative procedure.
b). Discharges meeting any of the requirements of Section 4.30.7.B.2.c.3). will be assigned an initial loading based upon the following information in order of preference:
i). The average monthly limit obtained from effluent guideline limitations promulgated by the U.S. Environmental Protection Agency for the point source category applicable to the discharge,
ii). Any average monthly limitation for the parameter in the current discharge permit,
iii). Monitoring data of sufficient quantity and quality, as determined by the Executive Director, to characterize the concentration of the parameter in the discharge, or
iv). Minimum performance standards established by the Executive Director for industrial and municipal wastewater treatment plants discharging to the tidal Delaware River.
In assigning the initial loading, the average loading at the appropriate criteria duration will be calculated using the coefficient of variation (CV) calculated from monitoring data or a default value of 0.6 in the absence of data of sufficient quantity and quality, as determined by the Executive Director.
c). Discharges contributing to an exceedance of a stream quality objective due to the cumulative effect of all discharges may not be required to provide additional treatment or loading reduction if the discharge does not represent a significant proportion of the marginal loading.
5). Allocations established by the Executive Director and reallocations required under Section 4.30.7.A.5.b.2). shall be published in a document containing the specific procedures, tools and assumptions used to derive the allocations.
6). Wasteload allocations established under Section 4.30.7.B.2.c. shall be referred to the appropriate agency of the signatory parties, respectively, for use, as appropriate, in developing effluent limitations, schedules of compliance, and other requirements in permits.
d. Adjustment for Pollutants in Intake Water. Wasteload allocations established for an industrial discharge may be adjusted by the Executive Director, in consultation with the appropriate agency of the signatory parties, to account for pollutants present in water withdrawn for use by the facility from the receiving water provided that the following conditions are met:
1). In the absence of pollutants in the water withdrawn, there would be no exceedance of the stream quality objectives for toxic pollutants;
2). Pollutants in the discharge resulting from any other activity, operation or materials used or produced at the facility do not significantly contribute to an exceedance of the stream quality objectives for toxic pollutants contained in Section 3.30.;
3). No statistically significant difference can be detected between the intake and effluent concentrations and loadings of a toxic pollutant based upon a rigorous analysis of data representative of operating and ambient conditions at the facility; and
4). No practicable alternative source of intake water is available.
g. Subsection 4.30.7C. is added to read as follows:
C. Definitions.
1. Wasteload Allocation. The portion of the Total Maximum Daily Load of a body of water or section thereof that is allocated to an existing or future point source of pollution. Or, any limitation on the loading and/or concentration of a pollutant discharged from a point source required to ensure that stream quality objectives are not exceeded.
2. Total Maximum Daily Load (TMDL). The maximum daily loading of a pollutant from all sources which still ensures that water quality objectives are met.
3. Margin of Safety. A factor that takes into account any uncertainty or lack of knowledge about the relationship between pollutant loadings and the quality of the receiving water.
4. Marginal Load. The portion of the loading of a pollutant that contributes to an exceedance of a stream quality objective when the cumulative loading from all point sources is considered.
5. Effluent Limitations Guidelines. Effluent limitations for pollutants for categories and classes of point sources promulgated by the U.S. Environmental Protection Agency under Section 301 of the Clean Water Act which reflect the best available treatment technology.
6. Harmonic Mean Flow. The flow value corresponding to the number of daily flow measurements divided by the sum of the reciprocals of the flows.
7. Background Concentration. The concentration of a toxic pollutant at any point in the Estuary that results from loadings from tributaries, sediments (if applicable), and any point or non-point sources not subject to control in the current allocation or reallocation.
8. Phase 1 Continuous Point Source Discharge. A discharge of wastewater other than non-contact cooling water, permitted under the National Pollutant Discharge Elimination System (NPDES) which occurs without interruption during the operating hours of a facility except for infrequent shutdowns, and is not primarily dependent on precipitation-induced flows.
9. Long-term Average Concentration. The mean concentration of a toxic pollutant in the effluent that represents the desired performance of a wastewater treatment plant.
10. Minimum Performance Standards. The long-term average concentration for a parameter for which stream quality objectives have been established under Section 3.10.3.C. or D.
a. For volatile and non-volatile organic chemicals, the standard is the maximum for a monthly average specified in the effluent guideline limitations for the Organic Chemicals, Plastics, and Synthetic Fibers (OCPSF) industrial category, or the highest reported effluent value for activated sludge treatment specified in the U.S. EPA's Water Engineering Research Laboratory data base.
b. For chlorinated pesticides and polychlorinated biphenyls, the standard is the Practical Quantitation Limit (PQL) for the compound.
c. For metals and indicator parameters, the standard is the average concentration of the parameter in industrial or municipal treatment plant discharges to the Estuary.
11. Initial Loading. The concentration or mass of a pollutant that is initially assigned to a discharge that meets the criteria specified in Section 4.30.7.B.2.c.3). during the baseline analysis portion of a wasteload allocation exercise.
3. Interpretive Guideline No. 1 of the Administrative Manual - Part III Water Quality Regulations is hereby amended as follows:
a. Subsection A.(1)a. is revised to read as follows:
a. Toxic Substances. The following limits shall apply in Basin waters other than Zones 2, 3, 4 and 5.
b. Subsection B.(2)b. is revised to read as follows:
b. Toxicity. The following requirements shall apply in Basin waters other than Zones 2, 3, 4 and 5.
4. a. This resolution shall become effective January 1, 1997 except as otherwise provided in Subsection b. below.
b. The Commission may extend the time within which the provisions of the resolution are effective as to 1) any applications now pending before the Commission or any signatory party or 2) any existing docket conditions which require compliance with the resolution.
Delaware River Basin Compact, 75 Stat. 688
SUSAN M. WEISMAN,
SecretaryFiscal Note: Fiscal Note 68-33 remains valid for the final adoption of the subject regulations.
Annex A TITLE 25. ENVIRONMENTAL PROTECTION PART V. DELAWARE RIVER BASIN COMMISSION CHAPTER 901. GENERAL PROVISIONS § 901.2. Comprehensive Plan and water quality
The Comprehensive Plan regulations as set forth in 18 CFR Part 401, Subpart A (1996) and the Water code and Water Quality Standards as set forth in 18 CFR Part 410 (1996) are hereby incorporated by reference and made a part of this title.
[Pa.B. Doc. No. 96-2092. Filed for public inspection December 13, 1996, 9:00 a.m.]
