In addition to the base user charges applicable pursuant to Section 929.02, users discharging pollutants to the wastewater treatment works whose average concentration, as defined in Section 925.07, in one or more classifications exceeds in any month that concentration defined as normal in Section 925.07 in the corresponding classification, shall be subject to surcharges calculated as follows:
(a) Surcharges for each billing period during a calendar year shall be based upon the following values for that calendar year: the estimated total operation and maintenance expense (Cto); the estimated total pounds of BOD received at the plant (Bt); and the estimated total pounds of suspended solids received at the plant (St). Data not available shall be estimated in the most practical manner possible.
(b) The surcharge on user charges per pound of BOD in excess of normal equals:
Cto x 0.05 Bt |
Until revised pursuant to the provisions of Section 929.06, the surcharge for BOD in excess of normal concentration shall be $0.05 per pound.
(c) The surcharge on user charges per pound of suspended solids in excess of normal equals:
Cto 0.10 St |
Until revised pursuant to the provisions of Section 929.06, the surcharge for suspended solids in excess of normal concentration shall be $0.07 per pound.
(d) Pounds of BOD per billing period subject to surcharge equals: (average concentration of BOD, calculated pursuant to Section 925.07, in milligrams per liter minus 200 milligrams per liter) times the volume of wastewater discharge from the user to the wastewater treatment works per billing period, in 100 cubic feet times 0.00624. If the average concentration of BOD is 200 milligrams per liter, or less, no surcharge for BOD shall apply.
(e) Pounds of suspended solids per billing period subject to surcharge equals: (average concentration of suspended solids, calculated pursuant to Section 925.07, in milligrams per liter minus 240 milligrams per liter) times the volume of wastewater discharged from the user to the wastewater treatment works per billing period, in 100 cubic feet times 0.00624. If the average concentration of suspended solids is 240 milligrams per liter, or less, no surcharge for suspended solids shall apply.
(f) The surcharge on user charges equals the pounds of BOD calculated pursuant to Section 929.03(d) times surcharge per pound calculated pursuant to Section 929.03(b); plus pounds of suspended solids calculated pursuant to Section 929.03(e); times surcharge per pound calculated pursuant to Section 929.03(c).
(g) Formulas as contained in Section 929.03(b) and (c) shall be subject to adjustment as necessary based upon annual audit of sewer revenue fund expenses.
(Ord. 1991-34. Passed 9-16-91.)