(a) Every industrial discharger which discharges "High Strength sewage" rather than, or in addition to "Normal sewage", either directly or indirectly, into the POTW shall be charged and pay a sewer system surcharge in addition to the sewerage service charge. Every person discharging sewage into the POTW having a concentration of any one or more of the sewage constituents described in subparagraph (1) of this paragraph (a), which is more than two (2) times the "Normal sewage" value of that sewage constituent, as defined in Section 916.01(w), shall be charged a base surcharge for the billing period. The surcharge will apply at all volumes discharged during a billing period above 15,000 gallons per day and shall be determined by the average daily discharge per billing period. Every person discharging sewage into the POTW having a concentration of any one or more of the sewage constituents described in subparagraph (1) of this paragraph (a), which is more than seven and one half (7.5) times the "High Strength sewage" value for that sewage constituent, as defined in Section 916.01(p), (i.e. a Slug or sometimes called a "Slug Load"), shall be charged an enhanced surcharge for the billing period.
(1) The amount of the surcharge shall be based on the levels of the following three sewage constituents pertinent to the wastewater being discharged into the POTW:
A. Total Suspended Solids (TSS)
B. Biochemical Oxygen Demand (CBOD)
C. Ammonia Nitrogen (NH3)
(2) Surcharges imposed under this paragraph (a) shall be calculated based on all constituent values over the "High Strength sewage" value for the concentration values for the sewage constituents described in subparagraph (1) of this paragraph (a) discharged by the customer during the billing period, as determined by use of the applicable formulas shown below.
"High Strength sewage" Formula:
SC1 = Q x (CV - SL - HSS) x 8.34 x SCR "Slug Load" Formula: SC2 = Q x SL x 8.34 x (SCR x 4) Wherein: SL = Surchargeable Slug Load concentration (mg/L). SL = CV - SLV (When SL is less than or equal to zero, the SL value used in the above formulas shall be zero.) SC1 = Surcharge for a constituent's High Strength sewage concentration ($). SC2 = Total charge for Slug Load surcharge for concentration ($). Q = Total quantity of the waste flow million gallons (MG). CV = Constituents concentration from sampling (mg/L). HSS = High Strength sewage value for constituent (mg/L). CBOD = 400 mg/L TSS = 500 mg/L NH3 = 30 mg/L SLV = Slug Load value for constituent (mg/L) CBOD = 3000 mg/L TSS = 3750 mg/L NH3 = 225 mg/L SCR = Base rate of surcharge per pound for constituent ($). Table Of Base Rates Of Surcharge Per Pound For Constituent High Strength sewage Slug Load value CBOD Surcharge per Lb $0.16 $0.64 TSS Surcharge per Lb $0.13 $0.52 NH3 Surcharge per Lb $0.60 $2.40 |
The total of all surcharges imposed under this paragraph (a) for a billing period shall be the sum of SC1 plus SC2 computed for each of the three constituents listed in Section 916.06(a)(1) [this may require six calculations and the summation of six surcharge numbers]. Surcharge amounts will be added to the discharger's bill for the billing period.
(3) The measurements described in Section 916.06(a)(2) shall be analytical measurements determined from samples taken from discharge points determined by the City at such a time or times, of such duration and in such a manner as the City may elect.
(4) If for any one or more of the sewage constituents described in Section 916.06(a)(1) the mass amount of the sewage constituent discharge for a sample is equivalent to five percent (5%) or more of the POTW Average Headworks Loading for that sewage constituent, as defined herein, the Director may establish a compliance schedule under which the customer must reduce the concentration of the discharged sewage constituent: (a) so that the discharge of the sewage constituent does not meet the definition of a slug; or (b) to a maximum mass discharge amount of four percent (4%) of the POTW Average Headworks Loading, whichever is greater. POTW Average Headworks Loading is defined as the average monthly mass amount of each sewage constituent, described in Section 916.06(a)(1), received by the POTW, as determined from the latest POTW influent analysis, less any process recycle loading in the most recent calendar year for which data is available.
(b) Industrial Users who seek greater consistency in the amount charged per billing period may make a written request to the Finance Director to receive what is known as an 'average monthly bill'. Upon approval, an average monthly bill shall mean, the amount billed for the remainder of the calendar year which shall be calculated using the average monthly surcharge for the previous one or three calendar years, whichever is greater. Average monthly bills will be recalculated and adjusted accordingly each calendar year.
An Industrial User may return to standard/actual monthly billing upon written request to the Finance Director. Industrial Users who return to standard/actual monthly billing will have the option of catching up any outstanding balance with either: (1) a one-time payment in full or (2) having the balance evenly distributed over the next 12 monthly bills. Once an Industrial User elects to return to standard/actual monthly billing they shall not be permitted to receive average monthly billing for a period of 18 months.