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ATTACHMENT 4 To 05-06-04 Draft MWMC Minutes 1.3 is the selected peaking to convert average dry season load to DSMM (dry season maximum month) load (based on 1990 to 2002 data) The key piece is the selected pounds per capita per day. Per capita loads, according to · the Master Plan, have been lower than the design capacity and the Master Plan identified the per capita load for BeD as 0.17. On two different occasions (the last time at the second public forum), Matt Noeson from CH2MHill assured me that the change in the per capita pounds per day from the 0.17 they had used in the Master Plan to the 0.19 being used now was not based upon any new data or any change in how the capacity should be calculated. [This is incorrect. The change was made based on an additional 7.5 years of flow and load data since the 1997 Master Plan] The .change in per capita load was done solely for the purpose of further reducing our chances of having a permit violation during a wet May. [This is incorrect. BOO would not be an issue even in a wet May. TSS would be the controlling factor] However, the effect on the amount of BOD.capacity is significant. The used capacity drops to 50,500 lbs per day. Changing the per capita load results in an additional 8.5% loss of BeD capacity. If we substitute the population figures that are used in the Draft facility plan for those used above, we have the following formula: (0.19 x 229,145 x 1.3) + 2,402 = 59,000 lbs per day [This. is not how the SDC values were calculated. This equation is using 2005 values for population. The SDC values were calculated based on 2002 population] that we are using of our 66,000 lbs/day capacity, we are now using 89.5% of our BeD capacity. This is the dilemma that we face. According the Master Plan prepared by CH2MHill seven years ago, we were using about 46% of our BeD capacity. According to DEQ, five years later, we are using approximately 60% of our capacity and our current facility would allow us to comply with our new permit requirements. However, according to CH2MHill and MWMC staff in the Draft Facility Plan, the sky is falling. As a ratepayer, I would feel most comfortable going with the more moderate assessment of DEQ and assume that we are using 60% of our BeD and TSS capacities and have 40% available for future use. The same argument applies to TSS capacity. According the Master Plan, we were using 46% of our TSS capacity seven years ago. According to DEQ in 2002, we were using. approximately 60% of our capacity. Using the population numbers in the facility plan and the formula provided by CH2MHill in the System Development Charge Methodology, we are generating the following amount of TS S: (0.21 x 229,145 x 1.4) + 2,224 = 69,593 lbs/day of TSS. [This is not how the $D¢ values were calculated. This equation is using 2005 values for population. The SDC values were calculated based on 2002 population] Our capacity is 71,600, so accdrding CH2MHill and MWMC staff, we are currently using 97% of our Attachment 4 Page 15 of 17 4-18