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Melanie Lawrence <br />September 30, 2009 <br />Page 2 <br />Depletions <br />This plan describes the projected uses for 2009. According to the information submitted, <br />no water surface was exposed within the permit boundary prior to January 1, 1981. <br />The anticipated consumptive use for 2009 consists of 30.63 acre-feet of evaporation loss <br />from an exposed ground water surface area of 10.1 acres and 2.5 acre-feet of water used for dust <br />control (total 33.13 acre-feet). The 10.1 acres of ground water was exposed due to previous <br />mining that occurred outside of the liner. In 2009, the Applicant will continue backfilling some of <br />the currently exposed pit with overburden material, thereby reducing the exposed ground water <br />surface area. This SWSP currently assumes that the entire 10.1 acres will be exposed for the <br />entire plan period. <br />The depletions from evaporation and dust control were lagged to the stream using a <br />Glover analysis and assuming a distance to the stream of 2,900 feet, distance to,the impermeable <br />boundary of 16,100 feet, permeability of 1,043 ft/day, saturated thickness of 20 feet and specific <br />yield of 0.2. The Applicant has provided a monthly schedule of lagged actual depletions to the <br />river system, together with a schedule of replacement requirements. This SWSP accounts for <br />actual depletions determined to accrue to the steam system during this plan period. <br />Replacements <br />The proposed source of replacement for this pit is water stored in priority within <br />Sharkey's Reservoir. The Applicant has stored 346.5 acre-feet in priority in Sharkey's Lake <br />between December 18, 2007 and July 30, 2009. This water was booked over into Sharkey's <br />Lake during periods of free-river and is a portion of the total calculated 663 acre-feet of water <br />stored in the material within the slurry wall lined pit. In 2008, 52 acre-feet was pumped from the <br />Lake for replacement purposes. For the period of January 1, 2009 through July 20, 2009 an <br />additional 23.14 acre-feet was released to cover 20.19 acre-feet of out-of-priority depletions, <br />even though an approved SWSP did not exist during this period. <br />The monthly consumptive use and lagged depletions for this plan period are shown in <br />the table below: <br />Month Consumptive Use <br />(acre-feet) Lagged Depletions <br />(acre-feet) <br />Aug 4.57 4.15 <br />Sep 3.66 4.08 <br />Oct 2.70 3.78 <br />Nov 1.24 3.27 <br />Dec 1.06 2.70 <br />Total 13.23 17.98