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Utah Division of Water Quality
Statement of Basis
ADDENDUM
Wasteload Analysis and Antidegradation Level I Review
Date: June 9, 2025
Prepared by: Suzan Tahir
Standards and Technical Services
Facility: McWane Ductile
UPDES No. UT0000612
Receiving water: Ironton Mill RaceProvo Bay of Utah Lake
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
001 Treatment plant discharge 3.5 MGD
Receiving Water
The discharge flows into Ironton Canal which is a tributary of Utah Lake. As per UAC R317-2-
13.5(c), the designated beneficial uses of Ironton Canal from Utah Lake (Provo Bay) to the east
boundary of the Denver and Rio Grande Western Railroad right-of-way are 2B, 3C, 4.
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 3C - Protected for nongame fish and other aquatic life, including the necessary
aquatic organisms in their food chain.
Class 4 - Protected for agricultural uses including irrigation of crops and stock watering.
Utah Division of Water Quality
Wasteload Analysis
McWane Ductile
UPDES No. UT0000612
Page 2 of 4
Critical Flow
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). The critical flow data was
calculated using data provided by the permittee for Ironton Weir for the period 2015-2024.
Season 7Q10 cfs
Summer 3.52
Fall 3.26
Winter 2.23
Spring 4.22
TMDL
According to DWQ’s 2024 Integrated Report and 303(d) Assessment, assessment unit UT-L-
16020201-004_02, (Provo Bay portion of Utah Lake), is listed as impaired for Ammonia,
Eutrophication, Harmful Algal Blooms, PCB in fish tissue, pH and total phosphorus.
Utah Lake is also listed as impaired for all the parameters and TDS .A TMDL has not been
completed for any of these constituents. If effluent concentrations for any of these constituents
exceed end of pipe water quality criteria, further analysis should be conducted to limit impacts to
downstream waters.
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. Streams with a flow equal to or less
than twice the flow of a point source discharge may be considered to be totally mixed.
Since the receiving water low flow (1.13 cfs) is equal to or less than twice the flow of a point
source discharge (5.43 cfs), the combined flows are considered to be totally mixed as per R317-2-
5.
Parameters of Concern
The potential parameters of concern identified for the discharge/receiving water were ammonia,
phosphorus, TDS and pH, based on review of the past permit and the impairment status of the
receiving water. Additional parameters of concern may become apparent as a result of reasonable
potential analysis, technology-based standards, or other factors as determined by the UPDES
Permit Writer.
Utah Division of Water Quality
Wasteload Analysis
McWane Ductile
UPDES No. UT0000612
Page 3 of 4
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 001: 60.7% effluent
Wasteload Allocation Methods
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.
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.
Antidegradation Review Level II Review
A Level II Antidegradation Review (ADR) is not required for this facility. The proposed permit
is a simple renewal of an existing UPDES permit. No increase in flow or concentration of
pollutants over those authorized in the existing permit is being requested.
Documents:
WLA Document : McWaneDuctile_WLADoc_6-9-2025.docx
Wasteload Analysis and Addendums:
McWaneDuctile_WLA_6-9-20265.xlsm,
McWaneDuctile_WLA _6-9-2025_VAR.pdf
McWaneDuctile_WLA_SOB_6-9-2025.pdf
Utah Division of Water Quality
Wasteload Analysis
McWane Ductile
UPDES No. UT0000612
Page 4 of 4
References:
Utah Division of Water Quality. 2024. Final 2024 Integrated Report on Water Quality
Utah Division of Water Quality. 2021. Utah Wasteload Analysis Procedures Version 2.0.
Lewis, B., J. Saunders, and M. Murphy. 2002. Ammonia Toxicity Model (AMMTOX, Version2): A Tool for
Determining Effluent Ammonia Limits. University of Colorado, Center for Limnology.
https://lf-public.deq.utah.gov/WebLink/DocView.aspx?id=14329&repo=Public&searchid=4ecc38d5-3973-4b1c-
a285-2e959fb813ef
https://provopw.org/resources/reports/water/canal/SpringCreekWebData.html
Utah Division of Water Quality
Salt Lake City, Utah
WASTELOAD ANALYSIS [WLA]9-Jun-25
Addendum: Statement of Basis 4:00 PM
Facilities: McWane Ductile UPDES No:UT-0000612
Discharging to: Ironton - Mill Race - Provo Bay of Utah Lake
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
Ironton - Mill Race - Provo Bay of Utah Lake:2B, 3C, 4
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) 5.00 mg/l (30 Day Average)
N/A mg/l (7Day Average)
3.00 mg/l (1 Day Average
Maximum Total Dissolved Solids 1200.0 mg/l
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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**2.544 lbs/day 750.00 ug/l 21.931 lbs/day
Arsenic 150.00 ug/l 4.386 lbs/day 340.00 ug/l 9.942 lbs/day
Cadmium 0.76 ug/l 0.022 lbs/day 8.73 ug/l 0.255 lbs/day
Chromium III 268.22 ug/l 7.843 lbs/day 5611.67 ug/l 164.089 lbs/day
ChromiumVI 11.00 ug/l 0.322 lbs/day 16.00 ug/l 0.468 lbs/day
Copper 30.50 ug/l 0.892 lbs/day 51.68 ug/l 1.511 lbs/day
Iron 1000.00 ug/l 29.241 lbs/day
Lead 18.58 ug/l 0.543 lbs/day 476.82 ug/l 13.942 lbs/day
Mercury 0.0120 ug/l 0.000 lbs/day 2.40 ug/l 0.070 lbs/day
Nickel 168.54 ug/l 4.928 lbs/day 1515.91 ug/l 44.326 lbs/day
Selenium 4.60 ug/l 0.135 lbs/day 20.00 ug/l 0.585 lbs/day
Silver N/A ug/l N/A lbs/day 41.07 ug/l 1.201 lbs/day
Zinc 387.83 ug/l 11.340 lbs/day 387.83 ug/l 11.340 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 400 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 0.044 lbs/day
Chlordane 0.004 ug/l 0.207 lbs/day 1.200 ug/l 0.035 lbs/day
DDT, DDE 0.001 ug/l 0.048 lbs/day 0.550 ug/l 0.016 lbs/day
Dieldrin 0.002 ug/l 0.091 lbs/day 1.250 ug/l 0.037 lbs/day
Endosulfan 0.056 ug/l 2.691 lbs/day 0.110 ug/l 0.003 lbs/day
Endrin 0.002 ug/l 0.111 lbs/day 0.090 ug/l 0.003 lbs/day
Guthion 0.010 ug/l 0.000 lbs/day
Heptachlor 0.004 ug/l 0.183 lbs/day 0.260 ug/l 0.008 lbs/day
Lindane 0.080 ug/l 3.844 lbs/day 1.000 ug/l 0.029 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 0.673 lbs/day 2.000 ug/l 0.058 lbs/day
Pentachlorophenol 15.00 ug/l 720.737 lbs/day 19.000 ug/l 0.556 lbs/day
Toxephene 0.0002 ug/l 0.010 lbs/day 0.7300 ug/l 0.021 lbs/day
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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 100.0 ug/l lbs/day
Boron 750.0 ug/l lbs/day
Cadmium 10.0 ug/l 0.15 lbs/day
Chromium 100.0 ug/l lbs/day
Copper 200.0 ug/l lbs/day
Lead 100.0 ug/l lbs/day
Selenium 50.0 ug/l lbs/day
TDS, Summer 1200.0 mg/l 17.54 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 129.73 lbs/day
Acrolein ug/l lbs/day 780.0 ug/l 37.48 lbs/day
Acrylonitrile ug/l lbs/day 0.7 ug/l 0.03 lbs/day
Benzene ug/l lbs/day 71.0 ug/l 3.41 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 0.21 lbs/day
Chlorobenzene ug/l lbs/day 21000.0 ug/l 1009.03 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 4.76 lbs/day
1,1,1-Trichloroethane
Hexachloroethane ug/l lbs/day 8.9 ug/l 0.43 lbs/day
1,1-Dichloroethane
1,1,2-Trichloroethane ug/l lbs/day 42.0 ug/l 2.02 lbs/day
1,1,2,2-Tetrachloroethane ug/l lbs/day 11.0 ug/l 0.53 lbs/day
Chloroethane 0.0 ug/l 0.00 lbs/day
Bis(2-chloroethyl) ether ug/l lbs/day 1.4 ug/l 0.07 lbs/day
2-Chloroethyl vinyl ether ug/l lbs/day 0.0 ug/l 0.00 lbs/day
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Utah Division of Water Quality
Salt Lake City, Utah
2-Chloronaphthalene ug/l lbs/day 4300.0 ug/l 206.61 lbs/day
2,4,6-Trichlorophenol ug/l lbs/day 6.5 ug/l 0.31 lbs/day
p-Chloro-m-cresol 0.0 ug/l 0.00 lbs/day
Chloroform (HM)ug/l lbs/day 470.0 ug/l 22.58 lbs/day
2-Chlorophenol ug/l lbs/day 400.0 ug/l 19.22 lbs/day
1,2-Dichlorobenzene ug/l lbs/day 17000.0 ug/l 816.84 lbs/day
1,3-Dichlorobenzene ug/l lbs/day 2600.0 ug/l 124.93 lbs/day
1,4-Dichlorobenzene ug/l lbs/day 2600.0 ug/l 124.93 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 0.15 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 37.96 lbs/day
1,2-Dichloropropane ug/l lbs/day 39.0 ug/l 1.87 lbs/day
1,3-Dichloropropylene ug/l lbs/day 1700.0 ug/l 81.68 lbs/day
2,4-Dimethylphenol ug/l lbs/day 2300.0 ug/l 110.51 lbs/day
2,4-Dinitrotoluene ug/l lbs/day 9.1 ug/l 0.44 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 0.03 lbs/day
Ethylbenzene ug/l lbs/day 29000.0 ug/l 1393.43 lbs/day
Fluoranthene ug/l lbs/day 370.0 ug/l 17.78 lbs/day
4-Chlorophenyl phenyl ether
4-Bromophenyl phenyl ether
Bis(2-chloroisopropyl) ether ug/l lbs/day 170000.0 ug/l 8168.36 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 76.88 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 17.30 lbs/day
Dichlorobromomethane(HM)ug/l lbs/day 22.0 ug/l 1.06 lbs/day
Chlorodibromomethane (HM)ug/l lbs/day 34.0 ug/l 1.63 lbs/day
Hexachlorobutadiene(c)ug/l lbs/day 50.0 ug/l 2.40 lbs/day
Hexachlorocyclopentadiene ug/l lbs/day 17000.0 ug/l 816.84 lbs/day
Isophorone ug/l lbs/day 600.0 ug/l 28.83 lbs/day
Naphthalene
Nitrobenzene ug/l lbs/day 1900.0 ug/l 91.29 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 672.69 lbs/day
4,6-Dinitro-o-cresol ug/l lbs/day 765.0 ug/l 36.76 lbs/day
N-Nitrosodimethylamine ug/l lbs/day 8.1 ug/l 0.39 lbs/day
N-Nitrosodiphenylamine ug/l lbs/day 16.0 ug/l 0.77 lbs/day
N-Nitrosodi-n-propylamine ug/l lbs/day 1.4 ug/l 0.07 lbs/day
Pentachlorophenol ug/l lbs/day 8.2 ug/l 0.39 lbs/day
Phenol ug/l lbs/day 4.6E+06 ug/l 2.21E+05 lbs/day
Bis(2-ethylhexyl)phthalate ug/l lbs/day 5.9 ug/l 0.28 lbs/day
Butyl benzyl phthalate ug/l lbs/day 5200.0 ug/l 249.86 lbs/day
Di-n-butyl phthalate ug/l lbs/day 12000.0 ug/l 576.59 lbs/day
Di-n-octyl phthlate
Diethyl phthalate ug/l lbs/day 120000.0 ug/l 5765.90 lbs/day
Dimethyl phthlate ug/l lbs/day 2.9E+06 ug/l 1.39E+05 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
Indeno(1,2,3-cd)pyrene (PAH)ug/l lbs/day 0.0 ug/l 0.00 lbs/day
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Utah Division of Water Quality
Salt Lake City, Utah
Pyrene (PAH)ug/l lbs/day 11000.0 ug/l 528.54 lbs/day
Tetrachloroethylene ug/l lbs/day 8.9 ug/l 0.43 lbs/day
Toluene ug/l lbs/day 200000 ug/l 9609.83 lbs/day
Trichloroethylene ug/l lbs/day 81.0 ug/l 3.89 lbs/day
Vinyl chloride ug/l lbs/day 525.0 ug/l 25.23 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 0.10 lbs/day
beta-Endosulfan ug/l lbs/day 2.0 ug/l 0.10 lbs/day
Endosulfan sulfate ug/l lbs/day 2.0 ug/l 0.10 lbs/day
Endrin ug/l lbs/day 0.8 ug/l 0.04 lbs/day
Endrin aldehyde ug/l lbs/day 0.8 ug/l 0.04 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 640.00 ug/l 30.75 lbs/day
Asbestos ug/l lbs/day
Beryllium
Cadmium
Chromium (III)
Chromium (VI)
Copper
Cyanide ug/l lbs/day 4.0E+02 ug/l 19.22 lbs/day
Lead ug/l lbs/day
Mercury 0.15 ug/l 0.01 lbs/day
Nickel 4600.00 ug/l 221.03 lbs/day
Selenium ug/l lbs/day
Silver ug/l lbs/day
Thallium 0.50 ug/l 0.02 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.
Page 6
Utah Division of Water Quality
Salt Lake City, Utah
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.
Current Upstream InformationStream
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 3.50 17.5 7.8 0.04 1.00 7.29 0.00 1016.7
Fall 3.30 14.0 7.4 0.03 1.00 --- 0.00 1050.0
Winter 2.20 13.8 7.6 0.03 1.00 --- 0.00 980.0
Spring 4.20 16.3 7.8 0.03 1.00 --- 0.00 971.3
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 2.385*0.795*0.0795*0.795*3.975*0.8*1.25*0.795*
Dissolved Hg Ni Se Ag Zn Boron
Metals ug/l ug/l ug/l ug/l ug/l ug/l
All Seasons 0.0000 0.795*1.59*0.15*0.0795*1.59** ~80% MDL
Projected Discharge Information
Season Flow, MGD Temp.
Summer 3.50000 29.0
Fall 3.50000 23.1
Winter 3.50000 20.0
Spring 3.50000 26.4
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 3.500 MGD 5.415 cfs
Fall 3.500 MGD 5.415 cfs
Winter 3.500 MGD 5.415 cfs
Spring 3.500 MGD 5.415 cfs
Flow Requirement or Loading Requirement
The calculations in this wasteload analysis utilize the maximum effluent discharge flow of 3.5 MGD. If the
discharger is allowed to have a flow greater than 3.5 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 >100.0%Effluent [Acute]
IC25 >60.7%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 18.0 mg/l as BOD5 525.3 lbs/day
Fall 18.0 mg/l as BOD5 525.3 lbs/day
Winter 18.0 mg/l as BOD5 525.3 lbs/day
Spring 18.0 mg/l as BOD5 525.3 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 5.00
Fall 5.00
Winter 5.00
Spring 5.00
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 2.45 mg/l as N 71.5 lbs/day
1 Hour Avg. - Acute 13.9 mg/l as N 406.9 lbs/day
Fall 4 Day Avg. - Chronic 3.6 mg/l as N 105.4 lbs/day
1 Hour Avg. - Acute 15.7 mg/l as N 457.3 lbs/day
Winter 4 Day Avg. - Chronic 3.6 mg/l as N 103.7 lbs/day
1 Hour Avg. - Acute 15.3 mg/l as N 445.3 lbs/day
Spring 4 Day Avg. - Chronic 4.5 mg/l as N 130.6 lbs/day
1 Hour Avg. - Acute 22.4 mg/l as N 652.7 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 0.017 mg/l 0.51 lbs/day
1 Hour Avg. - Acute 0.031 mg/l 0.89 lbs/day
Fall 4 Day Avg. - Chronic 0.017 mg/l 0.50 lbs/day
1 Hour Avg. - Acute 0.030 mg/l 0.87 lbs/day
Winter 4 Day Avg. - Chronic 0.015 mg/l 0.44 lbs/day
1 Hour Avg. - Acute 0.026 mg/l 0.77 lbs/day
Spring 4 Day Avg. - Chronic 0.019 mg/l 0.55 lbs/day
1 Hour Avg. - Acute 0.033 mg/l 0.96 lbs/day
Effluent Limitations for Total Dissolved Solids based upon Water Quality Standards
Season Concentration Load
Summer Maximum, Acute 1318.5 mg/l 19.24 tons/day
Fall Maximum, Acute 1297.0 mg/l 18.93 tons/day
Winter Maximum, Acute 1342.2 mg/l 19.59 tons/day
Spring Maximum, Acute 1347.8 mg/l 19.67 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 400 mg/l):
4 Day Average 1 Hour Average
Concentration Load Concentration Load
Aluminum*N/A N/A 991.6 ug/l 29.0 lbs/day
Arsenic*246.45 ug/l 4.6 lbs/day 449.6 ug/l 13.1 lbs/day
Cadmium 1.19 ug/l 0.0 lbs/day 11.5 ug/l 0.3 lbs/day
Chromium III 441.09 ug/l 8.3 lbs/day 7,425.1 ug/l 217.1 lbs/day
Chromium VI*15.54 ug/l 0.3 lbs/day 19.9 ug/l 0.6 lbs/day
Copper 49.70 ug/l 0.9 lbs/day 68.1 ug/l 2.0 lbs/day
Iron*N/A N/A 7,162.3 ug/l 209.4 lbs/day
Lead 30.08 ug/l 0.6 lbs/day 630.7 ug/l 18.4 lbs/day
Mercury*0.02 ug/l 0.0 lbs/day 3.2 ug/l 0.1 lbs/day
Nickel 276.97 ug/l 5.2 lbs/day 2,005.6 ug/l 58.6 lbs/day
Selenium*6.55 ug/l 0.1 lbs/day 26.0 ug/l 0.8 lbs/day
Silver N/A ug/l N/A lbs/day 54.3 ug/l 1.6 lbs/day
Zinc 638.47 ug/l 12.0 lbs/day 513.2 ug/l 15.0 lbs/day
Cyanide*8.56 ug/l 0.2 lbs/day 29.1 ug/l 0.9 lbs/day
*Limits for these metals are based on the dissolved standard.
Page 10
Utah Division of Water Quality
Salt Lake City, Utah
Effluent Limitations for Heat/Temperature based upon
Water Quality Standards
Summer 24.1 Deg. C.75.4 Deg. F
Fall 20.5 Deg. C.68.8 Deg. F
Winter 19.4 Deg. C.66.9 Deg. F
Spring 23.4 Deg. C.74.1 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 6.79E-02 lbs/day
Chlordane 4.30E-03 ug/l 1.25E-01 lbs/day 1.2E+00 ug/l 5.43E-02 lbs/day
DDT, DDE 1.00E-03 ug/l 2.92E-02 lbs/day 5.5E-01 ug/l 2.49E-02 lbs/day
Dieldrin 1.90E-03 ug/l 5.54E-02 lbs/day 1.3E+00 ug/l 5.65E-02 lbs/day
Endosulfan 5.60E-02 ug/l 1.63E+00 lbs/day 1.1E-01 ug/l 4.98E-03 lbs/day
Endrin 2.30E-03 ug/l 6.71E-02 lbs/day 9.0E-02 ug/l 4.07E-03 lbs/day
Guthion 0.00E+00 ug/l 0.00E+00 lbs/day 1.0E-02 ug/l 4.52E-04 lbs/day
Heptachlor 3.80E-03 ug/l 1.11E-01 lbs/day 2.6E-01 ug/l 1.18E-02 lbs/day
Lindane 8.00E-02 ug/l 2.33E+00 lbs/day 1.0E+00 ug/l 4.52E-02 lbs/day
Methoxychlor 0.00E+00 ug/l 0.00E+00 lbs/day 3.0E-02 ug/l 1.36E-03 lbs/day
Mirex 0.00E+00 ug/l 0.00E+00 lbs/day 1.0E-02 ug/l 4.52E-04 lbs/day
Parathion 0.00E+00 ug/l 0.00E+00 lbs/day 4.0E-02 ug/l 1.81E-03 lbs/day
PCB's 1.40E-02 ug/l 4.09E-01 lbs/day 2.0E+00 ug/l 9.05E-02 lbs/day
Pentachlorophenol 1.50E+01 ug/l 4.38E+02 lbs/day 1.9E+01 ug/l 8.59E-01 lbs/day
Toxephene 2.00E-04 ug/l 5.84E-03 lbs/day 7.3E-01 ug/l 3.30E-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 146.2 lbs/day
Nitrates as N 4.0 mg/l 117.0 lbs/day
Total Phosphorus as P 0.05 mg/l 1.5 lbs/day
Total Suspended Solids 90.0 mg/l 2631.7 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 4.45E+03 ug/l 1.30E+02 lbs/day
Acrolein 1.28E+03 ug/l 3.75E+01 lbs/day
Acrylonitrile 1.09E+00 ug/l 3.17E-02 lbs/day
Benzene 1.17E+02 ug/l 3.41E+00 lbs/day
Benzidine ug/l lbs/day
Carbon tetrachloride 7.24E+00 ug/l 2.11E-01 lbs/day
Chlorobenzene 3.46E+04 ug/l 1.01E+03 lbs/day
1,2,4-Trichlorobenzene
Hexachlorobenzene 1.27E-03 ug/l 3.70E-05 lbs/day
1,2-Dichloroethane 1.63E+02 ug/l 4.76E+00 lbs/day
1,1,1-Trichloroethane
Hexachloroethane 1.47E+01 ug/l 4.28E-01 lbs/day
1,1-Dichloroethane
1,1,2-Trichloroethane 6.91E+01 ug/l 2.02E+00 lbs/day
1,1,2,2-Tetrachloroethane 1.81E+01 ug/l 5.29E-01 lbs/day
Chloroethane
Bis(2-chloroethyl) ether 2.30E+00 ug/l 6.73E-02 lbs/day
2-Chloroethyl vinyl ether
2-Chloronaphthalene 7.08E+03 ug/l 2.07E+02 lbs/day
2,4,6-Trichlorophenol 1.07E+01 ug/l 3.12E-01 lbs/day
p-Chloro-m-cresol
Chloroform (HM)7.74E+02 ug/l 2.26E+01 lbs/day
2-Chlorophenol 6.59E+02 ug/l 1.92E+01 lbs/day
1,2-Dichlorobenzene 2.80E+04 ug/l 8.17E+02 lbs/day
1,3-Dichlorobenzene 4.28E+03 ug/l 1.25E+02 lbs/day
1,4-Dichlorobenzene 4.28E+03 ug/l 1.25E+02 lbs/day
3,3'-Dichlorobenzidine 1.27E-01 ug/l 3.70E-03 lbs/day
1,1-Dichloroethylene 5.27E+00 ug/l 1.54E-01 lbs/day
1,2-trans-Dichloroethylene1
2,4-Dichlorophenol 1.30E+03 ug/l 3.80E+01 lbs/day
1,2-Dichloropropane 6.42E+01 ug/l 1.87E+00 lbs/day
1,3-Dichloropropylene 2.80E+03 ug/l 8.17E+01 lbs/day
2,4-Dimethylphenol 3.79E+03 ug/l 1.11E+02 lbs/day
Page 12
Utah Division of Water Quality
Salt Lake City, Utah
2,4-Dinitrotoluene 1.50E+01 ug/l 4.37E-01 lbs/day
2,6-Dinitrotoluene
1,2-Diphenylhydrazine 8.89E-01 ug/l 2.59E-02 lbs/day
Ethylbenzene 4.77E+04 ug/l 1.39E+03 lbs/day
Fluoranthene 6.09E+02 ug/l 1.78E+01 lbs/day
4-Chlorophenyl phenyl ether
4-Bromophenyl phenyl ether
Bis(2-chloroisopropyl) ether 2.80E+05 ug/l 8.17E+03 lbs/day
Bis(2-chloroethoxy) methane
Methylene chloride (HM)2.63E+03 ug/l 7.69E+01 lbs/day
Methyl chloride (HM)
Methyl bromide (HM)
Bromoform (HM)5.93E+02 ug/l 1.73E+01 lbs/day
Dichlorobromomethane(HM)3.62E+01 ug/l 1.06E+00 lbs/day
Chlorodibromomethane (HM)5.60E+01 ug/l 1.63E+00 lbs/day
Hexachlorocyclopentadiene 2.80E+04 ug/l 8.17E+02 lbs/day
Isophorone 9.88E+02 ug/l 2.88E+01 lbs/day
Naphthalene
Nitrobenzene 3.13E+03 ug/l 9.13E+01 lbs/day
2-Nitrophenol
4-Nitrophenol
2,4-Dinitrophenol 2.30E+04 ug/l 6.73E+02 lbs/day
4,6-Dinitro-o-cresol 1.26E+03 ug/l 3.68E+01 lbs/day
N-Nitrosodimethylamine 1.33E+01 ug/l 3.89E-01 lbs/day
N-Nitrosodiphenylamine 2.63E+01 ug/l 7.69E-01 lbs/day
N-Nitrosodi-n-propylamine 2.30E+00 ug/l 6.73E-02 lbs/day
Pentachlorophenol 1.35E+01 ug/l 3.94E-01 lbs/day
Phenol 7.57E+06 ug/l 2.21E+05 lbs/day
Bis(2-ethylhexyl)phthalate 9.71E+00 ug/l 2.83E-01 lbs/day
Butyl benzyl phthalate 8.56E+03 ug/l 2.50E+02 lbs/day
Di-n-butyl phthalate 1.98E+04 ug/l 5.77E+02 lbs/day
Di-n-octyl phthlate
Diethyl phthalate 1.98E+05 ug/l 5.77E+03 lbs/day
Dimethyl phthlate 4.77E+06 ug/l 1.39E+05 lbs/day
Benzo(a)anthracene (PAH)5.10E-02 ug/l 1.49E-03 lbs/day
Benzo(a)pyrene (PAH)5.10E-02 ug/l 1.49E-03 lbs/day
Benzo(b)fluoranthene (PAH)5.10E-02 ug/l 1.49E-03 lbs/day
Benzo(k)fluoranthene (PAH)5.10E-02 ug/l 1.49E-03 lbs/day
Chrysene (PAH)5.10E-02 ug/l 1.49E-03 lbs/day
Acenaphthylene (PAH)
Anthracene (PAH)
Dibenzo(a,h)anthracene (PAH)5.10E-02 ug/l 1.49E-03 lbs/day
Indeno(1,2,3-cd)pyrene (PAH)5.10E-02 ug/l 1.49E-03 lbs/day
Pyrene (PAH)1.81E+04 ug/l 5.29E+02 lbs/day
Tetrachloroethylene 1.47E+01 ug/l 4.28E-01 lbs/day
Toluene 3.29E+05 ug/l 9.61E+03 lbs/day
Trichloroethylene 1.33E+02 ug/l 3.89E+00 lbs/day
Vinyl chloride 8.64E+02 ug/l 2.52E+01 lbs/day
Pesticides
Aldrin 2.30E-04 ug/l 6.73E-06 lbs/day
Dieldrin 2.30E-04 ug/l 6.73E-06 lbs/day
Chlordane 9.71E-04 ug/l 2.83E-05 lbs/day
4,4'-DDT 9.71E-04 ug/l 2.83E-05 lbs/day
4,4'-DDE 9.71E-04 ug/l 2.83E-05 lbs/day
4,4'-DDD 1.38E-03 ug/l 4.04E-05 lbs/day
alpha-Endosulfan 3.29E+00 ug/l 9.61E-02 lbs/day
beta-Endosulfan 3.29E+00 ug/l 9.61E-02 lbs/day
Endosulfan sulfate 3.29E+00 ug/l 9.61E-02 lbs/day
Page 13
Utah Division of Water Quality
Salt Lake City, Utah
Endrin 1.33E+00 ug/l 3.89E-02 lbs/day
Endrin aldehyde 1.33E+00 ug/l 3.89E-02 lbs/day
Heptachlor 3.46E-04 ug/l 1.01E-05 lbs/day
Heptachlor epoxide
PCB's
PCB 1242 (Arochlor 1242)7.41E-05 ug/l 2.16E-06 lbs/day
PCB-1254 (Arochlor 1254)7.41E-05 ug/l 2.16E-06 lbs/day
PCB-1221 (Arochlor 1221)7.41E-05 ug/l 2.16E-06 lbs/day
PCB-1232 (Arochlor 1232)7.41E-05 ug/l 2.16E-06 lbs/day
PCB-1248 (Arochlor 1248)7.41E-05 ug/l 2.16E-06 lbs/day
PCB-1260 (Arochlor 1260)7.41E-05 ug/l 2.16E-06 lbs/day
PCB-1016 (Arochlor 1016)7.41E-05 ug/l 2.16E-06 lbs/day
Pesticide
Toxaphene 1.23E-03 ug/l 3.60E-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)2.30E-08 ug/l 6.73E-10 lbs/day
Page 14
Utah Division of Water Quality
Salt Lake City, Utah
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 991.6 991.6 N/A
Antimony 1053.7 1053.7
Arsenic 164.6 449.6 164.6 246.4
Barium
Beryllium 0.0
Cadmium 16.4 11.5 11.5 1.2
Chromium (III)7425.1 7425.1 441.1
Chromium (VI)164.1 19.9 19.89 15.54
Copper 328.8 68.1 68.1 49.7
Cyanide 29.1 658.6 29.1 8.6
Iron 7162.3 7162.3
Lead 164.1 630.7 164.1 30.1
Mercury 3.18 0.25 0.25 0.020
Nickel 2005.6 7573.5 2005.6 277.0
Selenium 81.3 26.0 26.0 6.5
Silver 54.3 54.3
Thallium 0.8 0.8
Zinc 513.2 513.2 638.5
Boron 1234.8 1234.8
Sulfate 3292.8 3292.8
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 991.6 N/A
Antimony 1053.70
Arsenic 164.6 246.4 Acute Controls
Asbestos
Barium
Beryllium
Cadmium 11.5 1.2
Chromium (III)7425.1 441
Chromium (VI)19.9 15.5
Copper 68.1 49.7
Cyanide 29.1 8.6
Iron 7162.3
Lead 164.1 30.1
Mercury 0.247 0.020
Nickel 2005.6 277
Selenium 26.0 6.5
Silver 54.3 N/A
Thallium 0.8
Zinc 513.2 638.5 Acute Controls
Boron 1234.81
Sulfate 3292.8 N/A at this Waterbody
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.
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 is not required. The proposed permit is a simple renewal, with no
increase in flow or concentration over that which was approved in the existing permit.
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
Variable Flow-based Effluent Temperature Limits 6/9/2025 Date of Analysis
Substance:Heat
Discharger:McWane Ductile
Receiving Water: Ironton - Mill Race - Provo Bay of Utah Lake
Classification:2B, 3C, 4
Receiving Water Information
Flow cfs Deg. C.
Summer 3.50 17.5
Fall 3.30 14.0
Winter 2.20 13.8
Spring 4.20 16.3
Effluent Information
Flow MGD Flow cfs
Summer 3.5 5.41
Fall 3.5 5.41
Winter 3.5 5.41
Spring 3.5 5.41
Stream Standard
Temperature, Deg. C.27.0 Deg. C.
Temperature Increase, Deg. C.4.0 Deg. C.
Discharge Q (mgd)1.0 1.5 2.0 2.5 3.0 3.5 Effluent Limit Equation
summer 99.4 90.7 86.4 83.8 82.0 80.8 Tel=98. 047 Qe-0.165
fall 91.2 82.5 78.2 75.5 73.8 72.6 Tel=89.855 Qe-0.182
winter 86.6 77.9 73.5 70.9 69.1 67.9 Tel=85.204 Qe-0.193
spring 95.1 86.4 82.0 79.4 77.7 76.4 Tel=93.699 Qe-0.173
Tel = Effluent Limit (degrees F)
Qe = Effluent Flow (mgd)
Temperature Effluent Limits
(Degrees F)
y = 98.047x-0.165
R² = 0.9774
0.0
20.0
40.0
60.0
80.0
100.0
120.0
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0
Ef
f
l
u
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n
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T
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m
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a
t
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e
L
i
m
i
t
(
d
e
g
.
F
)
Effluent Q (mgd)
Summer
y = 89.855x-0.182
R² = 0.9783
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
80.0
90.0
100.0
0.0 1.0 2.0 3.0 4.0
Ef
f
l
u
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n
t
T
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p
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a
t
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L
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m
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t
(
D
e
g
.
F
)
Effluent Q (mgd)
Fall
y = 85.204x-0.193
R² = 0.9789
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
80.0
90.0
100.0
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0
Ef
f
l
u
e
n
t
T
e
m
p
e
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a
t
u
r
e
L
i
m
i
t
(
d
e
g
.
F
)
Effluent Q (mgd)
Winter
y = 93.699x-0.173
R² = 0.9779
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
80.0
90.0
100.0
0.0 1.0 2.0 3.0 4.0
Ef
f
l
u
e
n
t
T
e
m
p
e
r
a
t
u
r
e
L
i
m
i
t
(
d
e
g
.
F
)
Effluent Q (mgd)
Title