A. For waste strengths above normal strength of 200 mg/l BOD and 250 mg/l SS, a surcharge of five cents per pound BOD and two cents per pound SS shall be applied. The surcharge for each month period shall be computed by the following formulae:

SCBOD = (X-200) x A x 0.0000083 x $0.05

SCSS = (Y-250) x A x 0.0000083 x $0.02

where:

SCBOD = surcharge above the basic user rate for BOD concentration above 200 mg/l;

SCSS = surcharge above the basic user rate for SS concentration above 250 mg/l;

X = average BOD concentration in mg/l;

Y = average SS concentration in mg/l;

A = monthly metered water flow adjusted for appropriate losses in gallons.

B. Computation of Surcharge. The concentration of wastes used for computing surcharges shall be established by waste sampling. Waste sampling shall be performed as often as may be deemed necessary and shall be binding as a basis for surcharges.

C. Computation of Total Wastewater User Charge. The wastewater user charge shall be computed by the following formula:

CW = MC + BC + SCBOD + SCSS

where:

CW = total wastewater user charge;

MC = minimum charge as set out in Section 13.12.050;

BC = basic user charge as set out in Section 13.12.050;

SCBOD = surcharge for BOD as set out in subsection A of this section;

SCSS = surcharge for SS as set out in subsection A of this section. (Ord. 1979-7 § 8, 1979)