51.04 Discharging Industrial Wastes

(A) Each user who discharges industrial wastes into the Sewer System shall be subject to surcharge, in addition to the regular sewerage service charge, based on both the biochemical oxygen demand (or chemical oxygen demand where B.O.D. cannot be determined) and the suspended solids content of the wastes, if these wastes have a concentration greater than the following:

  1. A biochemical oxygen demand of 200 milligrams per liter; or where B.O.D. cannot be determined, then in lieu of B.O.D., a chemical oxygen demand of 400 milligrams per liter.
  2. A suspended solid content of 250 milligrams per liter.

(B) The rate of surcharge shall be based on the following:

  1. For biochemical oxygen demand, B.O.D. - $0.25/lb.
  2. For chemical oxygen demand, C.O.D. - $0.25/lb.
  3. For suspended solids, (SS) - $0.24/lb.

(C) The surcharge for excessive strength shall be determined by multiplying the difference between the average concentration computed in milligrams per liter of the B.O.D. (or C.O.D.) or of the suspended solids in the users' sewage and the allowed concentration defined in (A) above times 0.00834 times the appropriate surcharge rate specified in (B) above times the volume of water used in thousands of gallons. Sample calculation: Computed average strength of sewage = 300 mg/l B.O.D., 250 mg/l SS, volume of water used per month = 650,000 gallons. Surcharge = (300 - 200) X (.00834) (.06) X 650 = $32.50.

(D) (1) Any industrial wastes discharged into the public sewers shall be subject to periodic inspection and determination of character and concentration. The examination shall be made as often as the Superintendent deems it necessary (but at least once a year), and may include the use of suitable continuously monitoring instruments in appropriate cases. Samples shall be collected either manually or by approved mechanical devices and in such a manner as to be representative of the overall composition of the wastes. Sampling period shall be for a period of seven consecutive days, but may be of longer duration at the discretion of the city. In periods when the sampling program extends for a greater number of consecutive days than seven, the city shall have the prerogative of selecting the seven consecutive days of its choice. Every care shall be exercised in collecting the samples to insure their preservation, until analyzed, in a state comparable to that at the time the samples were collected.

(2) The installation, operation, and maintenance of the sampling facilities shall be the responsibility of the person discharging the wastes, and shall be subject to the approval of the Utility Board. Access to sampling facilities shall be granted at all times to the Superintendent or his duly authorized representative.

(E) Laboratory procedures used in the examination of industrial wastes shall be those set for in "Standard Methods". However, alternative methods for certain analyses of industrial wastes may be used subject to mutual agreement between the Superintendent and the customer. The city shall make, without charge to the customer, the initial analysis and regular periodic check analyses of the customer's wastes as well as other tests the Superintendent may deem advisable. Analyses made by the city at the request of the customer shall be charged to the customer according to the Board's standard work order billing practices. All such analyses shall be binding in determining strength-of-wastes surcharges and other matters dependent on the character and concentration of wastes.

(F) Until an adequate analysis of a representative sample of customer's wastes has been obtained, the city shall, for the purpose of this chapter, make a determination of the character and concentration of the customer's wastes by using date based on analyses of similar processes or data for his type of business that are available for the U. S. Environmental Protection Agency, or from industry-recognized authoritative sources. This method, if selected by the city, shall continue until an adequate analysis has been made.

(G) Review and acceptance by the Superintendent shall be obtained prior to the discharge into the sewer system by any user whose wastewater has a B.O.D. greater than 200 milligrams per liter, a suspended solids content greater than 250 milligrams per liter, or has contaminants or characteristics which from the nature or quantity might be harmful to the structures, processes, or operations of the sewage works, or to health, whether by themselves or through interacting with other wastes in public sewers. The city is authorized to require methods of pretreatment of said wastes as may be determined to be necessary to render the wastes acceptable to the sewer system.

(H) (1) Plans, specifications, and other pertinent information relating to proposed preliminary treatment or processing facilities shall be submitted to the city for examination and approval, and no construction of such facilities shall begin until the city, through its Utility Board, has given its written approval. Such approval shall not exempt the person from the obligation to make further reasonable adoptions of such facilities when such adaptations prove necessary to secure the results desired.

(2) Where such preliminary treatment facilities are provided, they shall be maintained continuously in satisfactory and effective operating condition by the person at his own expense, and shall be subject to periodic inspection by the city. The person shall maintain suitable operating records and shall submit to the superintendent such monthly summary reports of the character of the influent and effluent as the latter may prescribe.

(Ord. 17-1976, passed 7-6-76; Am. Ord. 3-1979, passed 2-19-79; Am. Ord. 14-1989, passed 5-1-89)