§ 51.041 SPECIFIC POLLUTANT LIMITATIONS.
   (A)   No person shall discharge to the POTW wastewater containing in excess of the following.
Pollutant
Mg/l
As measured by:
Pollutant
Mg/l
As measured by:
Arsenic
0.28 mg/l daily maximum
24-hour composite sample
Cadmium
0.17 mg/l daily maximum
24-hour composite sample
Copper
1.9 mg/l daily maximum
24-hour composite sample
Cyanide, Available
0.18 mg/l daily maximum (using Method OIA-1677 or city-approved equivalent)
Average of grab samples collected within a 24-hour period
Lead
1.4 mg/l daily maximum
24-hour composite sample
Mercury
<0.0002 mg/l daily maximuma (using EPA Method 245.1 or city-approved equivalent)
24-hour composite sample
Molybdenum
0.73 mg/l daily maximum
24-hour composite sample
Nickel
1.5 mg/l daily maximum
24-hour composite sample
Selenium
0.15 mg/l daily maximum
24-hour composite sample
Silver
0.052 mg/l daily maximum
24-hour composite sample
Total Chromium
2.3 mg/l daily maximum
24-hour composite sample
Hexavalent Chromium
0.19 mg/l daily maximum
Average of grab samples collected within a 24-hour period
Zinc
8.9. mg/l daily maximum
24-hour composite sample
Ammonia Nitrogen
23 mg/l daily maximumb
24-hour composite sample
Total Phenolics
0.92 mg/l daily maximumc (using EPA Method 420.1 or city-approved equivalent)
Average of grab samples collected within a 24-hour period
COD
User-specific daily maximum concentration based on BOD limit and average COD: BOD ratio for the POTW discharge, as measured a minimum of six times over a four-week period
24-hour composite sample
Fats, Oil and Grease
250 mg/l instantaneous maximum
Any grab sample
BOD
570 mg/l daily maximum
24-hour composite sample
Total Suspended Solids
280 mg/l daily maximum
24-hour composite sample
Phosphorus
12 mg/l daily maximum
24-hour composite sample
Total Dissolved Solids
3,500 mg/l monthly average
24-hour composite samples
6,900 mg/l daily maximum
24-hour composite sample
a   Below the level of quantification (LOQ) for EPA Method 245.1, which may be adjusted by the WWTP Superintendent on a case-by-case basis where there is laboratory-demonstrated sample matrix interference. Where deemed necessary by the WWTP Superintendent to meet requirements of the city’s Mercury pollutant minimization program, the administrator may specify a limit lower than 0.0002 mg/l and require low-level mercury testing with EPA Method 1631; in such cases, mercury sampling procedures shall comply with EPA Method 1669. Discharge to the POTW of quantifiable mercury using EPA Method 245.1 is prohibited, except as specifically approved by the WWTP Superintendent subject to the conditions listed below. Failure to comply with all conditions may result in revocation of this approval and subject the user to enforcement:
   (i)   The user shall have a city-accessible point for monitoring the discharge to the POTW. All costs for installation of this monitoring point shall be the user’s responsibility.
   (ii)   The user shall routinely self-monitor its effluent for mercury using a representative sample collected over the period of normal operation, tests conducted in accordance with the required EPA method, and at a frequency specified by the WWTP Superintendent. If the user contracts with a commercial laboratory to perform this sampling and/or analytical testing, all associated costs shall be the user’s responsibility.
   (iii)   The user shall develop and implement a pollutant minimization program (PMP) to establish actions and schedule commitments for reducing mercury entering the collection system. A PMP plan, which the user shall submit to the WWTP Superintendent for review and concurrence, shall address the following at a minimum: pretreatment system for removal of mercury; written procedures for disposal of mercury-contaminated wastes; new employee training and refresher training for current employees; review, and elimination, where feasible, of purchased materials containing mercury; and other activities deemed appropriate by the user or the WWTP Superintendent.
b   May be expressed as Total Kjeldahl Nitrogen (TKN) at the city’s discretion.
c   Applies to 2-Chlorophenol, 4-Chlorophenol, o-Cresol (i.e., 2-methylphenol), m-Cresol (i.e., 3-methylphenol), p-Cresol (i.e., 4-methylphenol), 2-Nitrophenol, 4-Nitrophenol, and Phenol. Discharge to the POTW of other phenolic compounds is prohibited without specific approval and development of pollutant-specific limits by the WWTP Superintendent.
 
      (1)   If any waters are discharged or are proposed to be discharged to the public sewers, which waters contain the substances or possess the characteristics enumerated above, and which in the judgement of the city may have a deleterious effect upon the sewage works, processes, equipment, or receiving waters, or which otherwise create a hazard to life or constitute a public nuisance, the city may do the following:
         (a)   Reject the wastes;
         (b)   Require pretreatment to the level defined as background sewage in division (B)(1) of this section;
         (c)   Issue a wastewater contribution permit, and require control over the quantities and rates of discharge to the POTW or pretreatment as necessary to comply with the maximum limits provided for in division (A) of this section; or
         (d)   Require payment to cover the added cast of handling and treating the wastes not covered by existing taxes and sewer charges.
      (2)   If control over quantities and rates of discharge to the POTW or if pretreatment is necessary, the design and installation of the plant and equipment shall be subject to the review and approval of the city and shall be subject to the requirements of all applicable codes, ordinances and laws.
   (B)   The city may prohibit the admission into the public sewers of any waters or wastes containing any of the following.
      (1)   Concentrations exceeding any of the background sewage constituents indicated below:
Pollutant
Mg/l
As measured by:
Pollutant
Mg/l
As measured by:
Arsenic
0.0016 mg/l monthly average
24-hour composite sample
Cadmium
0.00041 mg/l monthly average
24-hour composite sample
Copper
0.048 mg/l monthly average
24-hour composite sample
Cyanide, Available
<0.002 mg/l instantaneous maximum (using Method OIA-1677 or city-approved equivalent)
Grab sample
Lead
0.0023 mg/l monthly average
24-hour composite sample
Mercury
<0.0002 mg/l instantaneous maximum (using EPA Method 245.1 or city-approved equivalent)
24-hour composite sample
Molybdenum
0.0026 mg/l monthly average
24-hour composite sample
Nickel
0.0043 mg/l monthly average
24-hour composite sample
Selenium
0.00254 mg/l monthly average
24-hour composite sample
Silver
0.001 mg/l monthly average
24-hour composite sample
Total Chromium
0.00782 mg/l monthly average
24-hour composite sample
Hexavalent Chromium
<0.100 mg/l instantaneous maximum (using EPA Method 218.6 or city-approved equivalent)
Grab sample
Zinc
0.098 mg/l monthly average
24-hour composite sample
Ammonia Nitrogen (or TKN at the city's discretion)
20 mg/l monthly average
24-hour composite sample
Total Phenolics
0.92 mg/l monthly average (using EPA Method 420.1 or city-approved equivalent)
Grab sample
COD
500 mg/l monthly average
24-hour composite sample
Fats, Oil and Grease
31 mg/l monthly average
Grab sample
BOD
200 mg/l monthly average
24-hour composite sample
Total Suspended Solids
160 mg/l monthly average
24-hour composite sample
Phosphorus
4.3 mg/l monthly average
24-hour composite sample
Total Dissolved Solids
1,030 mg/l monthly average
24-hour composite sample
 
      (2)   Any quantity substances having the characteristics described in § 51.040.
      (3)   An average daily flow greater than 2% of the average daily sewage flow of the city, or having a rate of flow (gallows per day) greater than 10% of the average daily city flow for a period of one hour or more, which shall be subject to review and approval of the city.
(Ord. 257, passed 6-3-91; Am. Ord. 333, passed 5-16-16) Penalty, see § 51.999