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Home My WebLink AboutDWQ-2024-000931 Page 1 of 4 Utah Division of Water Quality Statement of Basis ADDENDUM Wasteload Analysis and Antidegradation Level I Review Date: February 3, 2023 Prepared by: Suzan Tahir Standards and Technical Services Facility: Perry/Willard Regional WWTP UPDES No. UT- 025721 Receiving water: Willard Spur Tailrace (2B, 3D) => Great Salt Lake Transitional Wetlands/Bear River National Wildlife Refuge (5E/2B, 3B, 3D) This addendum summarizes the wasteload analysis that was performed to determine water quality based effluent limits (WQBEL) for this discharge. Wasteload analyses are performed to determine point source effluent limitations necessary to maintain designated beneficial uses by evaluating projected effects of discharge concentrations on in-stream water quality. The wasteload analysis also takes into account downstream designated uses (UAC R317-2-8). Projected concentrations are compared to numeric water quality standards to determine acceptability. The numeric criteria in this wasteload analysis may be modified by narrative criteria and other conditions determined by staff of the Division of Water Quality. Discharge Outfall 001: The mean monthly discharge for the facility is 2 MGD (3.1 cfs). Receiving Water The receiving water for Outfall 001 is the Willard Spur tailrace, and then to the Great Salt Lake Transitional Wetlands/Bear River National Wildlife Refuge. Willard Spur Tailrace is classified as a 2B, 3E drainage canal/ditch as per UAC R317-2-13.10: • Class 2B - Protected for infrequent primary contact recreation. Also protected for secondary contact recreation where there is a low likelihood of ingestion of water or a low degree of bodily contact with the water. Examples include, but are not limited to, wading, hunting, and fishing. • Class 3E -- Severely habitat-limited waters. Narrative standards will be applied to protect these waters for aquatic wildlife. Utah Division of Water Quality Wasteload Analysis Perry/Willard Regional WWTP UPDES No. UT- 025721 Page 2 of 4 The receiving water of the Willard Spur tailrace is a combination of the Great Salt Lake Transitional Wetlands (5E) and the Bear River National Wildlife Refuge (2B, 3B, 3D). GSL Transitional Wetlands are classified as 5E as per UAC R317-2-13.11: • Class 5E - Protected for infrequent primary and secondary contact recreation, waterfowl, shore birds and other water-oriented wildlife including their necessary food chain. Waters within the Bear River National Wildlife Refuge are classified as 2B, 3B, 3D as per UAC R317-2-13.11: • Class 2B - Protected for infrequent primary contact recreation. Also protected for secondary contact recreation where there is a low likelihood of ingestion of water or a low degree of bodily contact with the water. Examples include, but are not limited to, wading, hunting, and fishing. • Class 3B -- Protected for warm water species of game fish and other warm water aquatic life, including the necessary aquatic organisms in their food chain. • Class 3D -- Protected for waterfowl, shore birds and other water-oriented wildlife not included in Classes 3A, 3B, or 3C, including the necessary aquatic organisms in their food chain. The hydrology in the area of the area of the Perry/Willard WWTP discharge is complicated and appears to vary considerably both seasonally and in relation to wet and dry climatic periods. A hydrologic assessment of the Willard Spur (CH2M HILL, 2016) summarized the findings of investigations conducted by DWQ and others over the last several years. Willard Spur water levels and the surface area over which the effluent spreads were identified as two most significant factors controlling the quantity of effluent reaching the open waters of the Willard Spur. Local runoff, irrigation return flow and leakage from Willard Reservoir into the Tailrace were characterized as likely reach the open waters of Willard Spur only during spring runoff and when water levels in Willard Spur are high. Evaporation and more significantly, infiltration rates appear to be high in periods when water levels in Willard Spur are low. The report noted that effluent discharged to the Willard Bay Tailrace was more likely to reach the open water of Willard Spur when water levels were low than if discharged to wetlands simply because the channel is deep and remains connected to the open water for most dry conditions. Typically, the critical flow for the wasteload analysis is considered the lowest stream flow for seven consecutive days with a ten year return frequency (7Q10) or alternatively, the 20th percentile value of available flow data. Due to a lack of flow records for the Willard Spur tailrace neither approach could be used. The critical low flow condition for Willard Spur tailrace was estimated at 0.1 cfs. To ensure protection of downstream uses, applicable water quality criteria associated with 2B, 3B and 3D uses classes will be met after complete mixing with the Willard Spur Tailrace. Ambient Utah Division of Water Quality Wasteload Analysis Perry/Willard Regional WWTP UPDES No. UT- 025721 Page 3 of 4 water quality for the Willard Spur tailrace was characterized by samples collected from DWQ sampling station 4920420, WB-RES-N-OUTLET (2011-2013). TMDL None of the receiving waters are listed on the state’s 2022 303(d) Water Quality Assessment. Mixing Zone The maximum allowable mixing zone is 15 minutes of travel time for acute conditions, not to exceed 50% of stream width, and 2,500 feet for chronic conditions, per UAC R317-2-5. Water quality standards must be met at the end of the mixing zone. The effluent was consider to be totally mixed as the ratio of receiving water flow (estimated 7Q10) to discharge flow was .03 (<=2). Acute limits were calculated using 50% of the seasonal critical low flow. Parameters of Concern The potential parameters of concern identified for the discharge/receiving water were ammonia and nutrients as determined in consultation with the UPDES Permit Writer. Nutrients controls are addressed in a separate document; Incorporating Results of Willard Spur Scientific Investigations into the UPDES Permit for the Perry-Willard POTW (DWQ 2016). WET Limits The percent of effluent in the receiving water in a fully mixed condition, and acute and chronic dilution in a not fully mixed condition are calculated in the WLA in order to generate WET limits. The LC50 (lethal concentration, 50%) percent effluent for acute toxicity and the IC25 (inhibition concentration, 25%) percent effluent for chronic toxicity, as determined by the WET test, needs to be below the WET limits, as determined by the WLA. The WET limit for LC50 is typically 100% effluent and does not need to be determined by the WLA. IC25 WET limits for Outfall 011 should be based on 96.9% effluent. Effluent Limits Effluent limits were determined for conservative constituents using a simple mass balance mixing analysis (UDWQ 2012). The mass balance analysis is summarized in the Wasteload Addendum. The water quality standard for chronic ammonia toxicity is dependent on temperature and pH, and the water quality standard for acute ammonia toxicity is dependent on pH. The AMMTOX Model developed by University of Colorado and adapted by Utah DWQ and EPA Region VIII was used to determine ammonia effluent limits (Lewis et al. 2002). The analysis is summarized in the Wasteload Addendum. Utah Division of Water Quality Wasteload Analysis Perry/Willard Regional WWTP UPDES No. UT- 025721 Page 4 of 4 Models and supporting documentation are available for review upon request. Antidegradation Level I Review The objective of the Level I ADR is to ensure the protection of existing uses, defined as the beneficial uses attained in the receiving water on or after November 28, 1975. No evidence is known that the existing uses deviate from the designated beneficial uses for the receiving water. Therefore, the beneficial uses will be protected if the discharge remains below the WQBELs presented in this wasteload. A Level II Antidegradation Review (ADR) is not required for this discharge since the pollutant concentration and load is not increasing under this permit renewal. Documents: WLA Document : Willard-PerryWLADoc_2023.docx Wasteload Analysis and Addendum: Willard-PerryWLADoc_2023.xlsm References: Utah Division of Water Quality. 2022. Final 2022 Integrated Report on Water Quality Utah Division of Water Quality. 2021. Utah Wasteload Analysis Procedures Version 2.0. CH2M HILL. 2016. Hydrology Assessment of Willard Spur, Great Salt Lake, 2011-2013: Development of Water Quality Standards for Willard Spur. Final report prepared for Utah Division of Water Quality. January 2016. DWQ, 2016.Incorporating Results of Willard Spur Scientific Investigations into the UPDES Permit for the Perry- Willard POTW. Utah Division of Water Quality Salt Lake City, Utah WASTELOAD ANALYSIS [WLA]30-Nov-22 Addendum: Statement of Basis 4:00 PM Facilities: Willard/Perry UPDES No:UT-025721 Discharging to:Willard Spur Tailrace-> 5E transitional Wetlands->BRMBR I. Introduction Wasteload analyses are performed to determine point source effluent limitations necessary to maintain designated beneficial uses by evaluating projected effects of discharge concentrations on in-stream water quality. The wasteload analysis also takes into account downstream designated uses [R317-2-8, UAC]. Projected concen- trations are compared to numeric water quality standards to determine acceptability. The anti-degradation policy and procedures are also considered. The primary in-stream parameters of concern may include metals (as a function of hardness), total dissolved solids (TDS), total residual chlorine (TRC), un-ionized ammonia (as a function of pH and temperature, measured and evaluated interms of total ammonia), and dissolved oxygen. Mathematical water quality modeling is employed to determine stream quality response to point source discharges. Models aid in the effort of anticipating stream quality at future effluent flows at critical environmental conditions (e.g., low stream flow, high temperature, high pH, etc). The numeric criteria in this wasteload analysis may always be modified by narrative criteria and other conditions determined by staff of the Division of Water Quality. II. Receiving Water and Stream Classification Willard Spur Tailrace-> 5E transitional Wetlands->BRMBR:2B,3B,3D,3E,5E Antidegradation Review:Level I review completed. Level II review not required. III. Numeric Stream Standards for Protection of Aquatic Wildlife Total Ammonia (TNH3)Varies as a function of Temperature and pH Rebound. See Water Quality Standards Chronic Total Residual Chlorine (TRC)0.011 mg/l (4 Day Average) 0.019 mg/l (1 Hour Average) Chronic Dissolved Oxygen (DO) 5.50 mg/l (30 Day Average) 4.00 mg/l (7Day Average) 3.00 mg/l (1 Day Average Maximum Total Dissolved Solids N/A mg/l Background Page 1 Utah Division of Water Quality Salt Lake City, Utah Acute and Chronic Heavy Metals (Dissolved) 4 Day Average (Chronic) Standard 1 Hour Average (Acute) Standard Parameter Concentration Load*Concentration Load* Aluminum 87.00 ug/l**1.454 lbs/day 750.00 ug/l 12.532 lbs/day Arsenic 190.00 ug/l 3.175 lbs/day 340.00 ug/l 5.681 lbs/day Cadmium 0.44 ug/l 0.007 lbs/day 4.09 ug/l 0.068 lbs/day Chromium III 145.65 ug/l 2.434 lbs/day 3047.28 ug/l 50.917 lbs/day ChromiumVI 11.00 ug/l 0.184 lbs/day 16.00 ug/l 0.267 lbs/day Copper 16.13 ug/l 0.270 lbs/day 25.60 ug/l 0.428 lbs/day Iron 1000.00 ug/l 16.709 lbs/day Lead 7.19 ug/l 0.120 lbs/day 184.58 ug/l 3.084 lbs/day Mercury 0.0120 ug/l 0.000 lbs/day 2.40 ug/l 0.040 lbs/day Nickel 89.70 ug/l 1.499 lbs/day 806.78 ug/l 13.480 lbs/day Selenium 4.60 ug/l 0.077 lbs/day 20.00 ug/l 0.334 lbs/day Silver N/A ug/l N/A lbs/day 11.39 ug/l 0.190 lbs/day Zinc 206.20 ug/l 3.445 lbs/day 206.20 ug/l 3.445 lbs/day * Allowed below discharge **Chronic Aluminum standard applies only to waters with a pH < 7.0 and a Hardness < 50 mg/l as CaCO3 Metals Standards Based upon a Hardness of 189.79 mg/l as CaCO3 Organics [Pesticides] 4 Day Average (Chronic) Standard 1 Hour Average (Acute) Standard Parameter Concentration Load*Concentration Load* Aldrin 1.500 ug/l 0.025 lbs/day Chlordane 0.004 ug/l 0.074 lbs/day 1.200 ug/l 0.020 lbs/day DDT, DDE 0.001 ug/l 0.017 lbs/day 0.550 ug/l 0.009 lbs/day Dieldrin 0.002 ug/l 0.033 lbs/day 1.250 ug/l 0.021 lbs/day Endosulfan 0.056 ug/l 0.964 lbs/day 0.110 ug/l 0.002 lbs/day Endrin 0.002 ug/l 0.040 lbs/day 0.090 ug/l 0.002 lbs/day Guthion 0.010 ug/l 0.000 lbs/day Heptachlor 0.004 ug/l 0.065 lbs/day 0.260 ug/l 0.004 lbs/day Lindane 0.080 ug/l 1.377 lbs/day 1.000 ug/l 0.017 lbs/day Methoxychlor 0.030 ug/l 0.001 lbs/day Mirex 0.010 ug/l 0.000 lbs/day Parathion 0.040 ug/l 0.001 lbs/day PCB's 0.014 ug/l 0.241 lbs/day 2.000 ug/l 0.033 lbs/day Pentachlorophenol 13.00 ug/l 223.804 lbs/day 20.000 ug/l 0.334 lbs/day Toxephene 0.0002 ug/l 0.003 lbs/day 0.7300 ug/l 0.012 lbs/day Page 2 Utah Division of Water Quality Salt Lake City, Utah IV. Numeric Stream Standards for Protection of Agriculture 4 Day Average (Chronic) Standard 1 Hour Average (Acute) Standard Concentration Load*Concentration Load* Arsenic ug/l lbs/day Boron ug/l lbs/day Cadmium ug/l #VALUE!lbs/day Chromium ug/l lbs/day Copper ug/l lbs/day Lead ug/l lbs/day Selenium ug/l lbs/day TDS, Summer mg/l tons/day V. Numeric Stream Standards for Protection of Human Health (Class 1C Waters) 4 Day Average (Chronic) Standard 1 Hour Average (Acute) Standard Metals Concentration Load*Concentration Load* Arsenic ug/l lbs/day Barium ug/l lbs/day Cadmium ug/l lbs/day Chromium ug/l lbs/day Lead ug/l lbs/day Mercury ug/l lbs/day Selenium ug/l lbs/day Silver ug/l lbs/day Fluoride (3)ug/l lbs/day to ug/l lbs/day Nitrates as N ug/l lbs/day Chlorophenoxy Herbicides 2,4-D ug/l lbs/day 2,4,5-TP ug/l lbs/day Endrin ug/l lbs/day Hexachlorocyclohexane (Lindane)ug/l lbs/day Methoxychlor ug/l lbs/day Toxaphene ug/l lbs/day VI. Numeric Stream Standards the Protection of Human Health from Water & Fish Consumption [Toxics] Maximum Conc., ug/l - Acute Standards Class 1C Class 3A, 3B Toxic Organics [2 Liters/Day for 70 Kg Person over 70 Yr.] [6.5 g for 70 Kg Person over 70 Yr.] Acenaphthene ug/l lbs/day 2700.0 ug/l 46.48 lbs/day Acrolein ug/l lbs/day 780.0 ug/l 13.43 lbs/day Acrylonitrile ug/l lbs/day 0.7 ug/l 0.01 lbs/day Benzene ug/l lbs/day 71.0 ug/l 1.22 lbs/day Benzidine ug/l lbs/day 0.0 ug/l 0.00 lbs/day Carbon tetrachloride ug/l lbs/day 4.4 ug/l 0.08 lbs/day Chlorobenzene ug/l lbs/day 21000.0 ug/l 361.53 lbs/day 1,2,4-Trichlorobenzene Hexachlorobenzene ug/l lbs/day 0.0 ug/l 0.00 lbs/day 1,2-Dichloroethane ug/l lbs/day 99.0 ug/l 1.70 lbs/day 1,1,1-Trichloroethane Hexachloroethane ug/l lbs/day 8.9 ug/l 0.15 lbs/day 1,1-Dichloroethane 1,1,2-Trichloroethane ug/l lbs/day 42.0 ug/l 0.72 lbs/day 1,1,2,2-Tetrachloroethane ug/l lbs/day 11.0 ug/l 0.19 lbs/day Chloroethane 0.0 ug/l 0.00 lbs/day Bis(2-chloroethyl) ether ug/l lbs/day 1.4 ug/l 0.02 lbs/day Page 3 Utah Division of Water Quality Salt Lake City, Utah 2-Chloroethyl vinyl ether ug/l lbs/day 0.0 ug/l 0.00 lbs/day 2-Chloronaphthalene ug/l lbs/day 4300.0 ug/l 74.03 lbs/day 2,4,6-Trichlorophenol ug/l lbs/day 6.5 ug/l 0.11 lbs/day p-Chloro-m-cresol 0.0 ug/l 0.00 lbs/day Chloroform (HM)ug/l lbs/day 470.0 ug/l 8.09 lbs/day 2-Chlorophenol ug/l lbs/day 400.0 ug/l 6.89 lbs/day 1,2-Dichlorobenzene ug/l lbs/day 17000.0 ug/l 292.67 lbs/day 1,3-Dichlorobenzene ug/l lbs/day 2600.0 ug/l 44.76 lbs/day 1,4-Dichlorobenzene ug/l lbs/day 2600.0 ug/l 44.76 lbs/day 3,3'-Dichlorobenzidine ug/l lbs/day 0.1 ug/l 0.00 lbs/day 1,1-Dichloroethylene ug/l lbs/day 3.2 ug/l 0.06 lbs/day 1,2-trans-Dichloroethylene1 ug/l lbs/day 0.0 ug/l 0.00 lbs/day 2,4-Dichlorophenol ug/l lbs/day 790.0 ug/l 13.60 lbs/day 1,2-Dichloropropane ug/l lbs/day 39.0 ug/l 0.67 lbs/day 1,3-Dichloropropylene ug/l lbs/day 1700.0 ug/l 29.27 lbs/day 2,4-Dimethylphenol ug/l lbs/day 2300.0 ug/l 39.60 lbs/day 2,4-Dinitrotoluene ug/l lbs/day 9.1 ug/l 0.16 lbs/day 2,6-Dinitrotoluene ug/l lbs/day 0.0 ug/l 0.00 lbs/day 1,2-Diphenylhydrazine ug/l lbs/day 0.5 ug/l 0.01 lbs/day Ethylbenzene ug/l lbs/day 29000.0 ug/l 499.25 lbs/day Fluoranthene ug/l lbs/day 370.0 ug/l 6.37 lbs/day 4-Chlorophenyl phenyl ether 4-Bromophenyl phenyl ether Bis(2-chloroisopropyl) ether ug/l lbs/day 170000.0 ug/l 2926.66 lbs/day Bis(2-chloroethoxy) methane ug/l lbs/day 0.0 ug/l 0.00 lbs/day Methylene chloride (HM)ug/l lbs/day 1600.0 ug/l 27.55 lbs/day Methyl chloride (HM)ug/l lbs/day 0.0 ug/l 0.00 lbs/day Methyl bromide (HM)ug/l lbs/day 0.0 ug/l 0.00 lbs/day Bromoform (HM)ug/l lbs/day 360.0 ug/l 6.20 lbs/day Dichlorobromomethane(HM)ug/l lbs/day 22.0 ug/l 0.38 lbs/day Chlorodibromomethane (HM)ug/l lbs/day 34.0 ug/l 0.59 lbs/day Hexachlorobutadiene(c)ug/l lbs/day 50.0 ug/l 0.86 lbs/day Hexachlorocyclopentadiene ug/l lbs/day 17000.0 ug/l 292.67 lbs/day Isophorone ug/l lbs/day 600.0 ug/l 10.33 lbs/day Naphthalene Nitrobenzene ug/l lbs/day 1900.0 ug/l 32.71 lbs/day 2-Nitrophenol ug/l lbs/day 0.0 ug/l 0.00 lbs/day 4-Nitrophenol ug/l lbs/day 0.0 ug/l 0.00 lbs/day 2,4-Dinitrophenol ug/l lbs/day 14000.0 ug/l 241.02 lbs/day 4,6-Dinitro-o-cresol ug/l lbs/day 765.0 ug/l 13.17 lbs/day N-Nitrosodimethylamine ug/l lbs/day 8.1 ug/l 0.14 lbs/day N-Nitrosodiphenylamine ug/l lbs/day 16.0 ug/l 0.28 lbs/day N-Nitrosodi-n-propylamine ug/l lbs/day 1.4 ug/l 0.02 lbs/day Pentachlorophenol ug/l lbs/day 8.2 ug/l 0.14 lbs/day Phenol ug/l lbs/day 4.6E+06 ug/l 7.92E+04 lbs/day Bis(2-ethylhexyl)phthalate ug/l lbs/day 5.9 ug/l 0.10 lbs/day Butyl benzyl phthalate ug/l lbs/day 5200.0 ug/l 89.52 lbs/day Di-n-butyl phthalate ug/l lbs/day 12000.0 ug/l 206.59 lbs/day Di-n-octyl phthlate Diethyl phthalate ug/l lbs/day 120000.0 ug/l 2065.88 lbs/day Dimethyl phthlate ug/l lbs/day 2.9E+06 ug/l 4.99E+04 lbs/day Benzo(a)anthracene (PAH)ug/l lbs/day 0.0 ug/l 0.00 lbs/day Benzo(a)pyrene (PAH)ug/l lbs/day 0.0 ug/l 0.00 lbs/day Benzo(b)fluoranthene (PAH)ug/l lbs/day 0.0 ug/l 0.00 lbs/day Benzo(k)fluoranthene (PAH)ug/l lbs/day 0.0 ug/l 0.00 lbs/day Chrysene (PAH)ug/l lbs/day 0.0 ug/l 0.00 lbs/day Acenaphthylene (PAH) Anthracene (PAH)ug/l lbs/day 0.0 ug/l 0.00 lbs/day Dibenzo(a,h)anthracene (PAH)ug/l lbs/day 0.0 ug/l 0.00 lbs/day Page 4 Utah Division of Water Quality Salt Lake City, Utah Indeno(1,2,3-cd)pyrene (PAH)ug/l lbs/day 0.0 ug/l 0.00 lbs/day Pyrene (PAH)ug/l lbs/day 11000.0 ug/l 189.37 lbs/day Tetrachloroethylene ug/l lbs/day 8.9 ug/l 0.15 lbs/day Toluene ug/l lbs/day 200000 ug/l 3443.13 lbs/day Trichloroethylene ug/l lbs/day 81.0 ug/l 1.39 lbs/day Vinyl chloride ug/l lbs/day 525.0 ug/l 9.04 lbs/day lbs/day Pesticides lbs/day Aldrin ug/l lbs/day 0.0 ug/l 0.00 lbs/day Dieldrin ug/l lbs/day 0.0 ug/l 0.00 lbs/day Chlordane ug/l lbs/day 0.0 ug/l 0.00 lbs/day 4,4'-DDT ug/l lbs/day 0.0 ug/l 0.00 lbs/day 4,4'-DDE ug/l lbs/day 0.0 ug/l 0.00 lbs/day 4,4'-DDD ug/l lbs/day 0.0 ug/l 0.00 lbs/day alpha-Endosulfan ug/l lbs/day 2.0 ug/l 0.03 lbs/day beta-Endosulfan ug/l lbs/day 2.0 ug/l 0.03 lbs/day Endosulfan sulfate ug/l lbs/day 2.0 ug/l 0.03 lbs/day Endrin ug/l lbs/day 0.8 ug/l 0.01 lbs/day Endrin aldehyde ug/l lbs/day 0.8 ug/l 0.01 lbs/day Heptachlor ug/l lbs/day 0.0 ug/l 0.00 lbs/day Heptachlor epoxide PCB's PCB 1242 (Arochlor 1242)ug/l lbs/day 0.0 ug/l 0.00 lbs/day PCB-1254 (Arochlor 1254)ug/l lbs/day 0.0 ug/l 0.00 lbs/day PCB-1221 (Arochlor 1221)ug/l lbs/day 0.0 ug/l 0.00 lbs/day PCB-1232 (Arochlor 1232)ug/l lbs/day 0.0 ug/l 0.00 lbs/day PCB-1248 (Arochlor 1248)ug/l lbs/day 0.0 ug/l 0.00 lbs/day PCB-1260 (Arochlor 1260)ug/l lbs/day 0.0 ug/l 0.00 lbs/day PCB-1016 (Arochlor 1016)ug/l lbs/day 0.0 ug/l 0.00 lbs/day Pesticide Toxaphene ug/l 0.0 ug/l 0.00 lbs/day Dioxin Dioxin (2,3,7,8-TCDD)ug/l lbs/day Metals Antimony ug/l lbs/day Arsenic ug/l lbs/day 4300.00 ug/l 74.03 lbs/day Asbestos ug/l lbs/day Beryllium Cadmium Chromium (III) Chromium (VI) Copper Cyanide ug/l lbs/day 2.2E+05 ug/l 3787.45 lbs/day Lead ug/l lbs/day Mercury 0.15 ug/l 0.00 lbs/day Nickel 4600.00 ug/l 79.19 lbs/day Selenium ug/l lbs/day Silver ug/l lbs/day Thallium 6.30 ug/l 0.11 lbs/day Zinc There are additional standards that apply to this receiving water, but were not considered in this modeling/waste load allocation analysis. Page 5 Utah Division of Water Quality Salt Lake City, Utah VII. Mathematical Modeling of Stream Quality Model configuration was accomplished utilizing standard modeling procedures. Data points were plotted and coefficients adjusted as required to match observed data as closely as possible. The modeling approach used in this analysis included one or a combination of the following models. (1) The Utah River Model, Utah Division of Water Quality, 1992. Based upon STREAMDO IV (Region VIII) and Supplemental Ammonia Toxicity Models; EPA Region VIII, Sept. 1990 and QUAL2E (EPA, Athens, GA). (2) Utah Ammonia/Chlorine Model, Utah Division of Water Quality, 1992. (3) AMMTOX Model, University of Colorado, Center of Limnology, and EPA Region 8 (4) Principles of Surface Water Quality Modeling and Control. Robert V. Thomann, et.al. Harper Collins Publisher, Inc. 1987, pp. 644. Coefficients used in the model were based, in part, upon the following references: (1) Rates, Constants, and Kinetics Formulations in Surface Water Quality Modeling. Environmen- tal Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, Athens Georgia. EPA/600/3-85/040 June 1985. (2) Principles of Surface Water Quality Modeling and Control. Robert V. Thomann, et.al. Harper Collins Publisher, Inc. 1987, pp. 644. VIII. Modeling Information The required information for the model may include the following information for both the upstream conditions at low flow and the effluent conditions: Flow, Q, (cfs or MGD)D.O. mg/l Temperature, Deg. C.Total Residual Chlorine (TRC), mg/l pH Total NH3-N, mg/l BOD5, mg/l Total Dissolved Solids (TDS), mg/l Metals, ug/l Toxic Organics of Concern, ug/l Other Conditions In addition to the upstream and effluent conditions, the models require a variety of physical and biological coefficients and other technical information. In the process of actually establishing the permit limits for an effluent, values are used based upon the available data, model calibration, literature values, site visits and best professional judgement. Model Inputs The following is upstream and discharge information that was utilized as inputs for the analysis. Dry washes are considered to have an upstream flow equal to the flow of the discharge. Page 6 Utah Division of Water Quality Salt Lake City, Utah Current Upstream Information Stream Critical Low Flow Temp.pH T-NH3 BOD5 DO TRC TDS cfs Deg. C mg/l as N mg/l mg/l mg/l mg/l Summer (Irrig. Season)0.1 24.5 8.0 0.03 1.50 --- 0.00 ### Fall 0.1 12.0 8.0 0.03 1.50 --- 0.00 ### Winter 0.1 7.4 8.0 0.03 1.50 --- 0.00 ### Spring 0.1 16.8 8.0 0.03 1.50 7.48 0.00 ### Dissolved Al As Cd CrIII CrVI Copper Fe Pb Metals ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l All Seasons 1.59*0.53*0.053*0.53*2.65*0.53*0.83*0.53* Dissolved Hg Ni Se Ag Zn Boron Metals ug/l ug/l ug/l ug/l ug/l ug/l All Seasons 0.0000 0.53*1.06*0.1*0.053*10.0 * 1/2 MDL Projected Discharge Information Season Flow, MGD Temp.TDS mg/l TDS tons/day Summer 2.00000 20.3 600.33 5.00575 Fall 2.00000 14.0 Winter 2.00000 10.8 Spring 2.00000 15.3 All model numerical inputs, intermediate calculations, outputs and graphs are available for discussion, inspection and copy at the Division of Water Quality. Page 7 Utah Division of Water Quality Salt Lake City, Utah IX. Effluent Limitations Current State water quality standards are required to be met under a variety of conditions including in-stream flows targeted to the 7-day, 10-year low flow (R317-2-9). Other conditions used in the modeling effort coincide with the environmental conditions expected at low stream flows. Effluent Limitation for Flow based upon Water Quality Standards In-stream criteria of downstream segments will be met with an effluent flow maximum value as follows: Season Daily Average Summer 2.000 MGD 3.094 cfs Fall 2.000 MGD 3.094 cfs Winter 2.000 MGD 3.094 cfs Spring 2.000 MGD 3.094 cfs Flow Requirement or Loading Requirement The calculations in this wasteload analysis utilize the maximum effluent discharge flow of 2 MGD. If the discharger is allowed to have a flow greater than 2 MGD during 7Q10 conditions, and effluent limit concentrations as indicated, then water quality standards will be violated. In order to prevent this from occuring, the permit writers must include the discharge flow limititation as indicated above; or, include loading effluent limits in the permit. Effluent Limitation for Whole Effluent Toxicity (WET) based upon WET Policy Effluent Toxicity will not occur in downstream segements if the values below are met. WET Requirements LC50 >EOP Effluent [Acute] IC25 >96.9%Effluent [Chronic] Page 8 Utah Division of Water Quality Salt Lake City, Utah Effluent Limitation for Biological Oxygen Demand (BOD) based upon Water Quality Standards or Regulations In-stream criteria of downstream segments for Dissolved Oxygen will be met with an effluent BOD limitation as follows: Season Concentration Summer 11.0 mg/l as BOD5 183.4 lbs/day Fall 11.0 mg/l as BOD5 183.4 lbs/day Winter 11.0 mg/l as BOD5 183.4 lbs/day Spring 11.0 mg/l as BOD5 183.4 lbs/day Effluent Limitation for Dissolved Oxygen (DO) based upon Water Quality Standards In-stream criteria of downstream segments for Dissolved Oxygen will be met with an effluent D.O. limitation as follows: Season Concentration Summer 5.50 Fall 5.50 Winter 5.50 Spring 5.50 Effluent Limitation for Total Ammonia based upon Water Quality Standards In-stream criteria of downstream segments for Total Ammonia will be met with an effluent limitation (expressed as Total Ammonia as N) as follows: Season Concentration Load Summer 4 Day Avg. - Chronic 5.3 mg/l as N 87.9 lbs/day 1 Hour Avg. - Acute 33.5 mg/l as N 558.8 lbs/day Fall 4 Day Avg. - Chronic 3.6 mg/l as N 59.4 lbs/day 1 Hour Avg. - Acute 9.5 mg/l as N 158.9 lbs/day Winter 4 Day Avg. - Chronic 5.0 mg/l as N 83.8 lbs/day 1 Hour Avg. - Acute 16.5 mg/l as N 275.3 lbs/day Spring 4 Day Avg. - Chronic 3.6 mg/l as N 59.4 lbs/day 1 Hour Avg. - Acute 9.5 mg/l as N 158.9 lbs/day Acute limit calculated with an Acute Zone of Initial Dilution (ZID) to be equal to 100.%. Page 9 Utah Division of Water Quality Salt Lake City, Utah Effluent Limitation for Total Residual Chlorine based upon Water Quality Standards In-stream criteria of downstream segments for Total Residual Chlorine will be met with an effluent limitation as follows: Season Concentration Load Summer 4 Day Avg. - Chronic 0.011 mg/l 0.19 lbs/day 1 Hour Avg. - Acute 0.020 mg/l 0.33 lbs/day Fall 4 Day Avg. - Chronic 0.011 mg/l 0.19 lbs/day 1 Hour Avg. - Acute 0.020 mg/l 0.33 lbs/day Winter 4 Day Avg. - Chronic 0.011 mg/l 0.19 lbs/day 1 Hour Avg. - Acute 0.020 mg/l 0.33 lbs/day Spring 4 Day Avg. - Chronic 0.011 mg/l 0.00 lbs/day 1 Hour Avg. - Acute 0.020 mg/l 0.00 lbs/day Effluent Limitations for Total Dissolved Solids based upon Water Quality Standards Season Concentration Load Summer Maximum, Acute None mg/l None tons/day Fall Maximum, Acute None mg/l None tons/day Winter Maximum, Acute None mg/l None tons/day Spring 4 Day Avg. - Chronic None mg/l None tons/day Colorado Salinity Forum Limits Determined by Permitting Section Effluent Limitations for Total Recoverable Metals based upon Water Quality Standards In-stream criteria of downstream segments for Dissolved Metals will be met with an effluent limitation as follows (based upon a hardness of 189.79 mg/l): 4 Day Average 1 Hour Average Concentration Load Concentration Load Aluminum N/A N/A 774.2 ug/l 12.9 lbs/day Arsenic 196.12 ug/l 2.1 lbs/day 351.0 ug/l 5.9 lbs/day Cadmium 0.45 ug/l 0.0 lbs/day 4.2 ug/l 0.1 lbs/day Chromium III 150.33 ug/l 1.6 lbs/day 3,145.7 ug/l 52.6 lbs/day Chromium VI 11.23 ug/l 0.1 lbs/day 16.4 ug/l 0.3 lbs/day Copper 16.62 ug/l 0.2 lbs/day 26.4 ug/l 0.4 lbs/day Iron N/A N/A 1,032.3 ug/l 17.2 lbs/day Lead 7.40 ug/l 0.1 lbs/day 190.5 ug/l 3.2 lbs/day Mercury 0.01 ug/l 0.0 lbs/day 2.5 ug/l 0.0 lbs/day Nickel 92.57 ug/l 1.0 lbs/day 832.8 ug/l 13.9 lbs/day Selenium 4.70 ug/l 0.1 lbs/day 20.6 ug/l 0.3 lbs/day Silver N/A ug/l N/A lbs/day 11.8 ug/l 0.2 lbs/day Zinc 212.87 ug/l 2.3 lbs/day 212.9 ug/l 3.6 lbs/day Cyanide 5.37 ug/l 0.1 lbs/day 22.7 ug/l 0.4 lbs/day Page 10 Utah Division of Water Quality Salt Lake City, Utah Effluent Limitations for Heat/Temperature based upon Water Quality Standards Summer 26.6 Deg. C.79.8 Deg. F Fall 14.1 Deg. C.57.3 Deg. F Winter 9.5 Deg. C.49.0 Deg. F Spring 18.9 Deg. C.66.0 Deg. F Effluent Limitations for Organics [Pesticides] Based upon Water Quality Standards In-stream criteria of downstream segments for Organics [Pesticides] will be met with an effluent limit as follows: 4 Day Average 1 Hour Average Concentration Load Concentration Load Aldrin 1.5E+00 ug/l 3.88E-02 lbs/day Chlordane 4.30E-03 ug/l 7.17E-02 lbs/day 1.2E+00 ug/l 3.10E-02 lbs/day DDT, DDE 1.00E-03 ug/l 1.67E-02 lbs/day 5.5E-01 ug/l 1.42E-02 lbs/day Dieldrin 1.90E-03 ug/l 3.17E-02 lbs/day 1.3E+00 ug/l 3.23E-02 lbs/day Endosulfan 5.60E-02 ug/l 9.34E-01 lbs/day 1.1E-01 ug/l 2.84E-03 lbs/day Endrin 2.30E-03 ug/l 3.84E-02 lbs/day 9.0E-02 ug/l 2.33E-03 lbs/day Guthion 0.00E+00 ug/l 0.00E+00 lbs/day 1.0E-02 ug/l 2.58E-04 lbs/day Heptachlor 3.80E-03 ug/l 6.34E-02 lbs/day 2.6E-01 ug/l 6.72E-03 lbs/day Lindane 8.00E-02 ug/l 1.33E+00 lbs/day 1.0E+00 ug/l 2.58E-02 lbs/day Methoxychlor 0.00E+00 ug/l 0.00E+00 lbs/day 3.0E-02 ug/l 7.75E-04 lbs/day Mirex 0.00E+00 ug/l 0.00E+00 lbs/day 1.0E-02 ug/l 2.58E-04 lbs/day Parathion 0.00E+00 ug/l 0.00E+00 lbs/day 4.0E-02 ug/l 1.03E-03 lbs/day PCB's 1.40E-02 ug/l 2.33E-01 lbs/day 2.0E+00 ug/l 5.17E-02 lbs/day Pentachlorophenol 1.30E+01 ug/l 2.17E+02 lbs/day 2.0E+01 ug/l 5.17E-01 lbs/day Toxephene 2.00E-04 ug/l 3.34E-03 lbs/day 7.3E-01 ug/l 1.89E-02 lbs/day Page 11 Utah Division of Water Quality Salt Lake City, Utah Effluent Targets for Pollution Indicators Based upon Water Quality Standards In-stream criteria of downstream segments for Pollution Indicators will be met with an effluent limit as follows: 1 Hour Average Concentration Loading Gross Beta (pCi/l)50.0 pCi/L BOD (mg/l)5.0 mg/l 83.5 lbs/day Nitrates as N 4.0 mg/l 66.8 lbs/day Total Phosphorus as P 0.05 mg/l 0.8 lbs/day Total Suspended Solids 90.0 mg/l 1503.8 lbs/day Note: Pollution indicator targets are for information purposes only. Effluent Limitations for Protection of Human Health [Toxics Rule] Based upon Water Quality Standards (Most stringent of 1C or 3A & 3B as appropriate.) In-stream criteria of downstream segments for Protection of Human Health [Toxics] will be met with an effluent limit as follows: Maximum Concentration Concentration Load Toxic Organics Acenaphthene 2.79E+03 ug/l 4.65E+01 lbs/day Acrolein 8.05E+02 ug/l 1.34E+01 lbs/day Acrylonitrile 6.81E-01 ug/l 1.14E-02 lbs/day Benzene 7.33E+01 ug/l 1.22E+00 lbs/day Benzidine ug/l lbs/day Carbon tetrachloride 4.54E+00 ug/l 7.57E-02 lbs/day Chlorobenzene 2.17E+04 ug/l 3.62E+02 lbs/day 1,2,4-Trichlorobenzene Hexachlorobenzene 7.95E-04 ug/l 1.33E-05 lbs/day 1,2-Dichloroethane 1.02E+02 ug/l 1.70E+00 lbs/day 1,1,1-Trichloroethane Hexachloroethane 9.19E+00 ug/l 1.53E-01 lbs/day 1,1-Dichloroethane 1,1,2-Trichloroethane 4.34E+01 ug/l 7.23E-01 lbs/day 1,1,2,2-Tetrachloroethane 1.14E+01 ug/l 1.89E-01 lbs/day Chloroethane Bis(2-chloroethyl) ether 1.45E+00 ug/l 2.41E-02 lbs/day 2-Chloroethyl vinyl ether 2-Chloronaphthalene 4.44E+03 ug/l 7.40E+01 lbs/day 2,4,6-Trichlorophenol 6.71E+00 ug/l 1.12E-01 lbs/day p-Chloro-m-cresol Chloroform (HM)4.85E+02 ug/l 8.09E+00 lbs/day 2-Chlorophenol 4.13E+02 ug/l 6.89E+00 lbs/day 1,2-Dichlorobenzene 1.75E+04 ug/l 2.93E+02 lbs/day 1,3-Dichlorobenzene 2.68E+03 ug/l 4.48E+01 lbs/day 1,4-Dichlorobenzene 2.68E+03 ug/l 4.48E+01 lbs/day 3,3'-Dichlorobenzidine 7.95E-02 ug/l 1.33E-03 lbs/day 1,1-Dichloroethylene 3.30E+00 ug/l 5.51E-02 lbs/day 1,2-trans-Dichloroethylene1 2,4-Dichlorophenol 8.16E+02 ug/l 1.36E+01 lbs/day 1,2-Dichloropropane 4.03E+01 ug/l 6.71E-01 lbs/day 1,3-Dichloropropylene 1.75E+03 ug/l 2.93E+01 lbs/day Page 12 Utah Division of Water Quality Salt Lake City, Utah 2,4-Dimethylphenol 2.37E+03 ug/l 3.96E+01 lbs/day 2,4-Dinitrotoluene 9.39E+00 ug/l 1.57E-01 lbs/day 2,6-Dinitrotoluene 1,2-Diphenylhydrazine 5.57E-01 ug/l 9.30E-03 lbs/day Ethylbenzene 2.99E+04 ug/l 4.99E+02 lbs/day Fluoranthene 3.82E+02 ug/l 6.37E+00 lbs/day 4-Chlorophenyl phenyl ether 4-Bromophenyl phenyl ether Bis(2-chloroisopropyl) ether 1.75E+05 ug/l 2.93E+03 lbs/day Bis(2-chloroethoxy) methane Methylene chloride (HM)1.65E+03 ug/l 2.75E+01 lbs/day Methyl chloride (HM) Methyl bromide (HM) Bromoform (HM)3.72E+02 ug/l 6.20E+00 lbs/day Dichlorobromomethane(HM)2.27E+01 ug/l 3.79E-01 lbs/day Chlorodibromomethane (HM)3.51E+01 ug/l 5.85E-01 lbs/day Hexachlorocyclopentadiene 1.75E+04 ug/l 2.93E+02 lbs/day Isophorone 6.19E+02 ug/l 1.03E+01 lbs/day Naphthalene Nitrobenzene 1.96E+03 ug/l 3.27E+01 lbs/day 2-Nitrophenol 4-Nitrophenol 2,4-Dinitrophenol 1.45E+04 ug/l 2.41E+02 lbs/day 4,6-Dinitro-o-cresol 7.90E+02 ug/l 1.32E+01 lbs/day N-Nitrosodimethylamine 8.36E+00 ug/l 1.39E-01 lbs/day N-Nitrosodiphenylamine 1.65E+01 ug/l 2.75E-01 lbs/day N-Nitrosodi-n-propylamine 1.45E+00 ug/l 2.41E-02 lbs/day Pentachlorophenol 8.47E+00 ug/l 1.41E-01 lbs/day Phenol 4.75E+06 ug/l 7.92E+04 lbs/day Bis(2-ethylhexyl)phthalate 6.09E+00 ug/l 1.02E-01 lbs/day Butyl benzyl phthalate 5.37E+03 ug/l 8.95E+01 lbs/day Di-n-butyl phthalate 1.24E+04 ug/l 2.07E+02 lbs/day Di-n-octyl phthlate Diethyl phthalate 1.24E+05 ug/l 2.07E+03 lbs/day Dimethyl phthlate 2.99E+06 ug/l 4.99E+04 lbs/day Benzo(a)anthracene (PAH)3.20E-02 ug/l 5.34E-04 lbs/day Benzo(a)pyrene (PAH)3.20E-02 ug/l 5.34E-04 lbs/day Benzo(b)fluoranthene (PAH)3.20E-02 ug/l 5.34E-04 lbs/day Benzo(k)fluoranthene (PAH)3.20E-02 ug/l 5.34E-04 lbs/day Chrysene (PAH)3.20E-02 ug/l 5.34E-04 lbs/day Acenaphthylene (PAH) Anthracene (PAH) Dibenzo(a,h)anthracene (PAH)3.20E-02 ug/l 5.34E-04 lbs/day Indeno(1,2,3-cd)pyrene (PAH)3.20E-02 ug/l 5.34E-04 lbs/day Pyrene (PAH)1.14E+04 ug/l 1.89E+02 lbs/day Tetrachloroethylene 9.19E+00 ug/l 1.53E-01 lbs/day Toluene 2.06E+05 ug/l 3.44E+03 lbs/day Trichloroethylene 8.36E+01 ug/l 1.39E+00 lbs/day Vinyl chloride 5.42E+02 ug/l 9.04E+00 lbs/day Pesticides Aldrin 1.45E-04 ug/l 2.41E-06 lbs/day Dieldrin 1.45E-04 ug/l 2.41E-06 lbs/day Chlordane 6.09E-04 ug/l 1.02E-05 lbs/day 4,4'-DDT 6.09E-04 ug/l 1.02E-05 lbs/day 4,4'-DDE 6.09E-04 ug/l 1.02E-05 lbs/day 4,4'-DDD 8.67E-04 ug/l 1.45E-05 lbs/day alpha-Endosulfan 2.06E+00 ug/l 3.44E-02 lbs/day beta-Endosulfan 2.06E+00 ug/l 3.44E-02 lbs/day Page 13 Utah Division of Water Quality Salt Lake City, Utah Endosulfan sulfate 2.06E+00 ug/l 3.44E-02 lbs/day Endrin 8.36E-01 ug/l 1.39E-02 lbs/day Endrin aldehyde 8.36E-01 ug/l 1.39E-02 lbs/day Heptachlor 2.17E-04 ug/l 3.62E-06 lbs/day Heptachlor epoxide PCB's PCB 1242 (Arochlor 1242)4.65E-05 ug/l 7.75E-07 lbs/day PCB-1254 (Arochlor 1254)4.65E-05 ug/l 7.75E-07 lbs/day PCB-1221 (Arochlor 1221)4.65E-05 ug/l 7.75E-07 lbs/day PCB-1232 (Arochlor 1232)4.65E-05 ug/l 7.75E-07 lbs/day PCB-1248 (Arochlor 1248)4.65E-05 ug/l 7.75E-07 lbs/day PCB-1260 (Arochlor 1260)4.65E-05 ug/l 7.75E-07 lbs/day PCB-1016 (Arochlor 1016)4.65E-05 ug/l 7.75E-07 lbs/day Pesticide Toxaphene 7.74E-04 ug/l 1.29E-05 lbs/day Metals Antimony ug/l lbs/day Arsenic ug/l lbs/day Asbestos ug/l lbs/day Beryllium Cadmium Chromium (III) Chromium (VI) Copper ug/l lbs/day Cyanide ug/l lbs/day Lead Mercury ug/l lbs/day Nickel ug/l lbs/day Selenium Silver Thallium ug/l lbs/day Zinc Dioxin Dioxin (2,3,7,8-TCDD)1.45E-08 ug/l 2.41E-10 lbs/day Metals Effluent Limitations for Protection of All Beneficial Uses Based upon Water Quality Standards and Toxics Rule Class 4 Acute Agricultural Class 3 Acute Aquatic Wildlife Acute Toxics Drinking Water Source Acute Toxics Wildlife 1C Acute Health Criteria Acute Most Stringent Class 3 Chronic Aquatic Wildlife ug/l ug/l ug/l ug/l ug/l ug/l ug/l Aluminum 774.2 774.2 N/A Antimony 4439.0 4439.0 Arsenic 351.0 0.0 351.0 196.1 Barium 0.0 Beryllium 0.0 Cadmium 4.2 0.0 4.2 0.4 Chromium (III)3145.7 0.0 3145.7 150.3 Page 14 Utah Division of Water Quality Salt Lake City, Utah Chromium (VI)16.4 0.0 16.39 11.23 Copper 26.4 26.4 16.6 Cyanide 22.7 227110.5 22.7 5.4 Iron 1032.3 1032.3 Lead 190.5 0.0 190.5 7.4 Mercury 2.48 0.15 0.0 0.15 0.012 Nickel 832.8 4748.7 832.8 92.6 Selenium 20.6 0.0 20.6 4.7 Silver 11.8 0.0 11.8 Thallium 6.5 6.5 Zinc 212.9 212.9 212.9 Boron 774.2 774.2 Summary Effluent Limitations for Metals [Wasteload Allocation, TMDL] [If Acute is more stringent than Chronic, then the Chronic takes on the Acute value.] WLA Acute WLA Chronic ug/l ug/l Aluminum 774.2 N/A Antimony 4438.98 Arsenic 351.0 196.1 Asbestos 0.00E+00 Barium Beryllium Cadmium 4.2 0.4 Chromium (III)3145.7 150 Chromium (VI)16.4 11.2 Copper 26.4 16.6 Cyanide 22.7 5.4 Iron 1032.3 Lead 190.5 7.4 Mercury 0.155 0.012 Nickel 832.8 93 Selenium 20.6 4.7 Silver 11.8 N/A Thallium 6.5 Zinc 212.9 212.9 Boron 774.24 Other Effluent Limitations are based upon R317-1. E. coli 126.0 organisms per 100 ml Page 15 Utah Division of Water Quality Salt Lake City, Utah X. Antidegradation Considerations The Utah Antidegradation Policy allows for degradation of existing quality where it is determined that such lowering of water quality is necessary to accommodate important economic or social development in the area in which the waters are protected [R317-2-3]. It has been determined that certain chemical parameters introduced by this discharge will cause an increase of the concentration of said parameters in the receiving waters. Under no conditions will the increase in concentration be allowed to interfere with existing instream water uses. The antidegradation rules and procedures allow for modification of effluent limits less than those based strictly upon mass balance equations utilizing 100% of the assimilative capacity of the receiving water. Additional factors include considerations for "Blue-ribbon" fisheries, special recreational areas, threatened and endangered species, and drinking water sources. An Antidegradation Level I Review was conducted on this discharge and its effect on the receiving water. Based upon that review, it has been determined that an Antidegradation Level II Review was not required. XI. Colorado River Salinity Forum Considerations Discharges in the Colorado River Basin are required to have their discharge at a TDS loading of less than 1.00 tons/day unless certain exemptions apply. Refer to the Forum's Guidelines for additional information allowing for an exceedence of this value. This doesn’t apply to facilities that do not discharge to the Colorado River Basin. XII. Summary Comments The mathematical modeling and best professional judgement indicate that violations of receiving water beneficial uses with their associated water quality standards, including important down- stream segments, will not occur for the evaluated parameters of concern as discussed above if the effluent limitations indicated above are met. Page 16 Utah Division of Water Quality Salt Lake City, Utah XIII. Notice of UPDES Requirement This Addendum to the Statement of Basis does not authorize any entity or party to discharge to the waters of the State of Utah. That authority is granted through a UPDES permit issued by the Utah Division of Water Quality. The numbers presented here may be changed as a function of other factors. Dischargers are strongly urged to contact the Permits Section for further information. Permit writers may utilize other information to adjust these limits and/or to determine other limits based upon best available technology and other considerations provided that the values in this wasteload analysis [TMDL] are not compromised. See special provisions in Utah Water Quality Standards for adjustments in the Total Dissolved Solids values based upon background concentration. Utah Division of Water Quality 801-538-6052 File Name: Willard_Perry_WLA_2023 APPENDIX - Coefficients and Other Model Information CBOD CBOD CBOD REAER.REAER.REAER.NBOD NBOD Coeff.Coeff.Coeff.Coeff.Coeff.Coeff.Coeff.Coeff. (Kd)20 FORCED (Ka)T (Ka)20 FORCED (Ka)T (Kn)20 (Kn)T 1/day (Kd)/day 1/day (Ka)/day 1/day 1/day 1/day 1/day 2.000 0.000 1.727 99.264 0.000 92.009 0.600 0.469 Open Open NH3 NH3 NO2+NO3 NO2+NO3 TRC TRC Coeff.Coeff.LOSS LOSS Decay (K4)20 (K4)T (K5)20 (K5)T (K6)20 (K6)T K(Cl)20 K(Cl)(T) 1/day 1/day 1/day 1/day 1/day 1/day 1/day 1/day 0.000 0.000 4.000 3.453 0.000 0.000 32.000 26.557 BENTHIC BENTHIC DEMAND DEMAND (SOD)20 (SOD)T gm/m2/day gm/m2/day 1.000 0.817 K1 K2 K3 K4 K5 K6 K(Cl)S CBOD Reaer. NH3 Open NH3 Loss NO2+3 TRC Benthic {theta} {theta} {theta} {theta} {theta} {theta}{theta} {theta} 1.0 1.0 1.1 1.0 1.0 1.0 1.1 1.1 Page 17 Utah Division of Water Quality Salt Lake City, Utah Antidegredation Review An antidegradation review (ADR) was conducted to determine whether the proposed activity complies with the applicable antidegradation requirements for receiving waters that may be affected. The Level I ADR evaluated the criteria of R317-2-3.5(b) and determined that a Level II Antidegradation Review is not required. Page 18