(A) Persons generating abnormal industrial waste may discharge the waste into the sanitary sewer provided:
(1) The waste will not cause interference;
(2) The waste will not endanger or be harmful to the operating personnel of the sewer system;
(3) The waste will not cause damage to the collection system;
(4) The waste will not impair the treatment processes;
(5) The waste will not affect sludge quality and/or require modifications in sludge disposal practices;
(6) The waste will not have an affect on receiving water quality;
(7) The discharge is in compliance with all limitations and requirements in this chapter;
(8) The waste shall be assessed a surcharge for any abnormal levels of BOD or TOC, TSS and FOG or TPH. There shall be one surcharge rate for BOD, TOC, FOG, or TPH, and a separate rate for TSS; and
(9) All required permits are in force and approval in writing has been given by the director for any waivers or special agreements.
(B) (1) Computation of the surcharge for the abnormal industrial waste shall be based on the following formulas:
S = V (8.34 [X (BOD/TOC-220 + Y (TSS-220) + Z (FOG-100) + Z (TPH-20)].
S = Surcharge in dollars that will appear on the customer's monthly bill.
V = Volume of wastewater discharge from user, in millions of gallons. This volume may be calculated from discharge meter or by a percentage of water consumption, as determined by the director.
8.34 = Pounds per gallon of water.
X = Unit charge in dollars per pound of BOD or TOC ($0.13).
BOD = BOD strength in milligrams per liter (mg/l).
TOC = Total organic carbon strength in milligrams per liter (mg/l).
220 = Normal BOD/TOC strength in milligrams per liter (mg/l).
Y = Unit charge in dollars per pound for TSS ($0.10).
TSS = Total suspended solids concentration in milligrams per liter (mg/l).
220 = Normal TSS concentration in milligrams per liter (mg/l).
Z = Unit charge in dollars per pound for FOG and TPH ($0.25).
FOG = Fats, oil, and grease concentration in milligrams per liter (mg/l).
TPH - Total petroleum hydrocarbons in mg/l.
100 = Normal FOG concentration in mg/l.
20 = Normal TPH concentration in mg/l.
X, Y, and Z values shall be set by the city council from time to time.
(2) If the strength or concentration for BOD, TOC, TSS, FOG or TPH is less than the normal strength for that category, there shall be no surcharge for that category, nor shall there be a credit given to the total surcharge if the strength or concentration of all three categories is less than the normal. Surcharges payable under this division shall become due monthly after the effective date of the surcharge.
(3) All BOD, TOC, FOG, TPH and TSS values in determining the surcharge shall be reevaluated and adjusted to reflect any changes in wastewater characteristics as sampling results deem it necessary.
(Ord. 041718, passed 4-17-2018)