§ 52.011 LOCAL LIMITS FOR SPECIFIC POLLUTANTS.
   (A)   Generally. Local limits for specific pollutants discharged pursuant to this subchapter shall be as follows:
      (1)   Dilution. Dilution of the discharge from a pretreatment facility or from a regulated process is prohibited as a method for treatment of wastes in order to meet the limits set forth in this section.
      (2)   Sample location. Measurement of pollutant concentrations to determine compliance shall be made at the point immediately following the pretreatment facility and before mixture with other waters, unless another point is designated by the WRA Director. If necessary, the concentrations so measured shall be recomputed to exclude the effect of any dilution that is improper using the combined waste stream formula.
   (B)   Headworks limits; average mass. The average composite loading of all industrial users contributing the following specific pollutants to the POTW shall not exceed the allowable total pounds. The allocation of pollutants between industrial and nonindustrial sources may be adjusted by the Director provided that the allowable total loading for any pollutant at the headworks of the WRF is not exceeded
 
30-Day Average Allowable Pounds/Day
Pollutant
Total
Industrial
BOD
195,600
135,153
TSS
300,400
208,463
NH3
13,000
6,959
TKN
27,760
16,950
 
Maximum Allowable Headworks Loading Pounds/Day
Maximum Allowable Industrial Loading Pounds/Day
Pollutant
Total
Industrial
Maximum Allowable Headworks Loading Pounds/Day
Maximum Allowable Industrial Loading Pounds/Day
Pollutant
Total
Industrial
Arsenic-T
7.58
3.81
Cadmium-T
3.65
2.16
Chromium-T
136.35
120.90
Copper-T
148.56
125.51
Cyanide-T
17.08
8.28
Lead-T
28.17
20.94
Mercury-T
0.999
0.747
Nickel-T
87.27
75.75
Silver-T
23.30
19.77
Zinc-T
360.59
283.53
 
   (C)   Discharge concentration limits and review criteria. Discharge concentration limits and review criteria shall be as follows:
      (1)   The discharge into the POTW of any materials, water or waste having a pollutant concentration greater than the limits in divisions (C)(3), (4), and (5) of this section or containing pollutants not listed in this division shall be subject to the review and approval of the WRA Director. After review of the proposed discharges, the WRA Director may:
         (a)   Reject the waste for reasons consistent with § 52.005.
         (b)   Require pretreatment to an acceptable pollutant concentration for discharge to the POTW.
         (c)   Require control of the quantities and rates of discharge of the water or waste.
         (d)   Require payment to cover the added cost of handling and treatment of water and waste or any combination thereof.
         (e)   Reduce the maximum or average mass loading of present and prospective individual users on any reasonable prorated basis to meet headworks loading limits at the WRF.
         (f)   Require the user to obtain a wastewater discharge permit and be subject to any of the rules and regulations contained therein.
         (g)   Require the user to meet local limits when local limits are more restrictive than National Categorical Pretreatment Standards, provided that headworks loading limits are met.
         (h)   Initiate enforcement action in response to any noncompliance with this subchapter using the enforcement procedures outlined in this chapter.
         (i)   Take any combination of the steps in divisions (C)(1)(a) through (C)(1)(g), as appropriate.
      (2)   Users discharging wastewater to the POTW whose pollutant concentrations or flows are greater than the following shall be considered industrial users for purposes of sewer charges and may be regulated or permitted by the WRA Director as appropriate:
Pollutant
Daily Maximum (mg/l)
Pollutant
Daily Maximum (mg/l)
BOD
200
TSS
250
COD
300
O&G-T
100
TKN
30
NH3-N
15
An average daily flow greater than 5,000 gallons or having an unusual concentration of flow.
 
      (3)   Pollutant limits. Average and maximum concentration limits for users without national categorical pretreatment standards for these pollutants shall be as follows:
Pollutant
Daily Maximum (mg/l)
Monthly Average (mg/l)
Pollutant
Daily Maximum (mg/l)
Monthly Average (mg/l)
Arsenic-T
0.38
0.25
Cadmium-T
0.08
0.05
Chromium-T
6.43
4.29
Copper-T
10.21
6.80
Cyanide-T
0.53
0.36
Lead-T
1.43
0.95
Mercury-T
0.042
0.028
Nickel-T
7.22
4.81
O&G-T
400.0
- -
O&G-Mineral
100.0
- -
Silver-T
1.30
0.87
VPH
10.0
- -
Zinc-T
19.64
13.09
pH range shall be not lower than 5.0 or greater than 12.0.
Temperature (liquids or vapors) shall be not greater than 150 degrees Fahrenheit at the point of entry into the POTW.
 
      (4)   Daily maximum pollutant limits for hauled waste. Daily maximum pollutant limits for hauled waste. Wastes delivered to the WRF by truck or rail shall not exceed the following concentrations in any load or overall daily loading limits unless otherwise approved by the WRA Director:
Pollutant
Concentration (mg/l)
Loading (pounds/day)
Pollutant
Concentration (mg/l)
Loading (pounds/day)
COD
100,000
--
O&G-T
50,000
--
VPH
10.0
--
Arsenic-T
--
0.014
Cadmium-T
--
0.93
Chromium-T
--
24.74
Copper-T
--
23.71
Cyanide-T
--
0.29
Lead-T
--
6.70
Mercury-T
--
0.12
Nickel-T
--
3.71
Silver-T
--
0.26
Zinc-T
--
87.62
pH range shall be not lower than 5.0 or greater than 12.0.
 
      (5)   Daily maximum limit for gasoline cleanup projects. Discharge of wastewater from sites where gasoline is being removed from the soil or groundwater shall meet the following limits prior to discharge to the POTW:
 
Pollutant
mg/l
Benzene
0.050
BETX
0.750
 
   (D)   No division of this section shall be construed to provide lesser discharge standards than are or that may be imposed and required by U.S. Environmental Protection Agency or the Iowa Department of Natural Resources, nor to allow the average allowable total loading for any pollutant at the headworks of the WRF to be exceeded.
(Ord. 2010-09, passed 7-13-2010; Am. Ord. 2019-03, passed 2-26-2019; Am. Ord. 2022-09, passed 8-23-2022)