(A) Wastewater having strengths in excess of the concentrations set forth in § 50.020 shall be surcharged at the following rates:
Discharge/Concentration | Surcharge | |||
CBOD5, mg/l | TSS, mg/l | COD, mg/l | NH3-N, mg/l | |
>250 but <400 | >250 but <400 | >500 but <600 | >25 but <30 | $0.18 per second |
>400 but <500 | >400 but <500 | >600 but <700 | >30 but <40 | $0.25 per second |
>500 | >500 | >700 | >40 | Written agreement as contained in § 50.063 |
(B) Surcharges shall be calculated as follows:
(1) Actual concentration of the discharge minus the maximum allowable concentration (from the table above) times the appropriate surcharge rate times the number of days of discharge. The surcharge amount will be based on the actual concentration of the discharge.
(2) Example: CBOD = 450 mg/l
Daily flow = 0.050 MGD
Number of days discharged = 15
450-250 200 mg/l × 0.050 MGD × 8.34 Ib/gal 83.4 lbs/day
83.4 lbs/day × $0.25 $20.85/day × 15 days $312.75 (amount of surcharge added to utility bill)
(Ord. 02-09, passed 5-28-02)