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<br /> <br />Exhibit A <br />APPENDIX B <br />Capacity Parameter Allocation Basis <br />System Capacity Parameters are based on permitting requirements. Facility process <br />components (defined in Appendix A) are allocated to each of the system capacity <br />parameters, as described below. <br />Collection System Pipelines <br />This category consists of major gravity sewer pipelines and force mains (pressure lines) that <br />convey flow for the regional wastewater collection system. Since the primary function of the <br />pipelines is to convey flow, the allocation is assigned to either average or peak flow and <br />none to wastewater strength parameters (i.e., BOD and TSS). The majority of the time the <br />conveyance system is carrying average flows. However, the limiting design criteria when <br />sizing pipelines is based on peak flows. <br />An assessment of the wet season I/I, which is the key driver in determining the peak flows, <br />can be used as a guide in determining the average/peak allocation breakdown. Table B-1 <br />presents the wet season I/I as a percentage of total peak flow for existing capacity, current <br />loading, and future required capacity. <br />TABLE B-1 <br />Design Criteria Basis For Unit Processes Driven By Peak Flow <br />Average Wet Weather I/I as a <br />Wet Weather I/I Total Peak Flow <br />Flow Percentage of Total Peak <br /> (mgd) (mgd) (mgd) Flow, % <br />Existing capacity 49 126 175 72% <br />Current loading (current 43.8 220.2 264 83% <br />capacity required) <br />a <br />Projected 2025 loading 59.3 218.7 277 79% <br />(future capacity required) <br />Notes: <br />a) Net reduction in total I/I occurs between now and 2025 as a result of I/I reduction efforts by the cities. <br />The range of wet weather I/I as a percentage of total peak flow for these three scenarios <br />ranges from 72 to 84 percent. The arithmetic average of these three values is 78 percent. <br />Therefore, a reasonable approach is to allocate a quarter to functional use basis, or average <br />flow; and three quarters to the design criteria sizing basis, or peak flow. <br />? <br />Average Flow – 1/4 <br /> <br />? <br />Peak Flow – 3/4 <br /> <br />Page 23 OF 39 <br /> <br /> <br /> <br />