§ 50.151 INDUSTRIAL PRETREATMENT CHARGES.
   (A)   Definitions. For the purposes of this section, the following definitions shall apply unless the context clearly indicates or requires a different meaning.
      AMMONIA NITROGEN. The quantity of nitrogen in the form of ammonia (NH3) as determined by laboratory analysis expressed in parts per million by weight.
      BIOCHEMICAL OXYGEN DEMAND (BOD) (also known as BOD5). The quantity of oxygen utilized in the biochemical oxidation of organic matter under standard laboratory procedure, five days at 20 degrees Celsius expressed in terms of weight and concentration in milligrams per liter (mg/l).
      CHEMICAL OXYGEN DEMAND (or COD). COD of sewage, sewage effluent, polluted waters or industrial wastes is a measure of the oxygen equivalent of that portion of the organic matter in a sample that is susceptible to oxidation by a strong chemical oxidant. The laboratory determination shall be made in accordance with procedures set forth in 40 CRF 136.
      DOMESTIC WASTEWATER. Wastewater from typical residential users and having pollutant characteristics of not greater than 250 mg/l BOD and 250 mg/l suspended solids and 20 mg/l ammonia nitrogen.
      INDUSTRIAL WASTES. The wastewater from industrial or commercial processes as distinct from domestic or sanitary wastes.
      OIL AND GREASE. A group of substances, including hydrocarbons, fatty acids, soaps, fats, waxes, oils or any other material that is extracted by a solvent from the acidified sample that is not volatilized during the laboratory test procedures. OIL AND GREASES are defined by the method of their determination in accordance with 40 CFR 136.
      SHALL. Is mandatory.
      SURCHARGE. A charge for services in addition to the basic sewer user and debt service charges, for those users whose contributions contain biochemical oxygen demand (BOD5), chemical oxygen demand (COD), total suspended solids (TSS), oil and grease or ammonia-nitrogen (NH3-N) and thiocyanate (SCN) in concentrations which exceed limits specified herein for such pollutants. Where authorized by the control authority, payment of a surcharge will authorize the discharge of the referenced pollutants so long as the discharge does not cause pass through or interference.
      SUSPENDED SOLIDS (TSS). Total suspended matter that either floats on the surface of, or is in suspension in, water, wastewater, or other liquids and that is removable by laboratory filtering as prescribed in "Standard Methods for the Examination of Water and Wastewater".
      THIOCYANATE. The quantity of thiocyanate (SCN) as determined by laboratory analysis expressed in parts per million by weight.
   (B)   Surcharges.
      (1)   (a)   Sewage or industrial wastes above normal domestic wastewater concentrations as defined herein but acceptable for discharge into the sewer system shall be subject to a surcharge.
         (b)   Maximum allowable concentrations without surcharges:
 
Parameter
Limits
Units
Ammonia Nitrogen (NH3-N)
20
mg/l
BOD5
250
mg/l
COD
658
mg/l
Oil & Grease (Total)
50
mg/l
Suspended Solids (Total)
250
mg/l
Thiocyanate
0
mg/l
 
      (2)   (a)   Any user discharging wastewater exceeding the maximum allowable concentration as noted above, shall be subject to a surcharge fee for each pound loading over and above the set limit as listed below:
 
Ammonia Nitrogen (NH3-N)
$0.5327/pound
Biochemical Oxygen Demand (BOD5)
$0.2193/pound
Oil & Grease
$0.5007/pound
Suspended Solids (Total)
$0.2706/pound
Thiocyanate
As stated below
 
         (b)   A unit weight of thiocyanate will produce 0.24 unit weight of ammonia and therefore 24% of all thiocyanate loading shall be surcharged as ammonia.
      (C)   Other industrial pretreatment charges. In addition to the above, all users shall pay a separate sewer user charge, fee or assessment for monitoring, inspections, surveillance, discharge reviews, construction, appeals, permit applications, consulting engineering, etc. as established by separate ordinances.
(Ord. 36, 2023, passed 3-24-23)