§ 28-154. Excessive strength charges.

For any user, when the BOD exceeds 250 mg/L (maximum limit for average domestic waste), the suspended solids exceeds 250 mg/l (maximum limit for average domestic waste), or when other pollutant concentrations exceed the range of concentrations of these pollutants in normal domestic sewage, a surcharge shall be added to the basic charge unless the user has a pretreatment permit and is in compliance with permit requirements as set forth in section 28-167 of Article IV, Division 3. This surcharge shall be calculated by the following formula:

C _s = [B _c (B) + P _c (P)] V _u

(Based on Model No. 2, 40 CFR 35. Appendix B.)

Symbols and definitions:

C _s  = A surcharge for wastewaters of excessive strength.

B _c  = O&M cost for treatment of a unit of biochemical oxygen demand (BOD).

B  = Concentration of BOD from a user above a base level.

S _s  = O&M cost for treatment of a unit of suspended solids (SS).

S  = Concentration of SS from a user above a base level.

P _c  = O&M cost for treatment of a unit of any pollutant.

P  = Concentration of any pollutant from a user above a base level.

V _u  = Volume contribution from a user per unit of time.

(Ord. No. 85-1206, Art. II, 12-17-85; Ord. No. 2016-04, § 1, 3-22-16)