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7 <br />Mr. Rick Parsons, P.E. <br />February 22, 2010 <br />Page 2 <br />Depletions <br />This plan describes the projected uses for 2010 and 2011. According to the information <br />submitted, no water surface was exposed within the permit boundary prior to January 1, 1981. <br />The Sharkey's Pond currently exposes approximately 8 acres of ground water. The 8 acres of <br />ground water was exposed due to previous mining that occurred outside of the liner. In 2009, the <br />Applicant backfilling some of the currently exposed pit with overburden material, thereby reducing the <br />exposed ground water surface area. Therefore from the previous SWSP approval the surface area of the <br />Sharkey's Pond has been reduced from 10.1 acre to the current 8 acres. <br />The anticipated consumptive use for 2010 and 2011 consists of 22.9 acre-feet annually of <br />evaporation loss from an exposed ground water surface area of 8 acres and 5 acre-feet annually of water <br />used for dust control (total 27.9 acre-feet annually). In 2010 and 2011, the Applicant will continue <br />backfilling some of the currently exposed pit with overburden material, thereby reducing the exposed <br />ground water surface area. This SWSP currently assumes that the entire 8 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 Glover <br />analysis and assuming a distance to the stream of 1,000 feet, distance to the impermeable boundary of <br />16,100 feet, transmissvity of 156,000 gpd/ft and a specific yield of 0.2. The Applicant has provided a <br />monthly schedule of lagged actual depletions to the river system, together with a schedule of replacement <br />requirements. This SWSP accounts for actual depletions determined to accrue to the steam system <br />during this plan period. <br />Replacements <br />The proposed source of replacement for this pit is water stored in priority within Sharkey's <br />Reservoir. The Applicant has stored 346.5 acre-feet in priority in Sharkey's Lake between December <br />18, 2007 and July 30,: 2009. This water was booked over into Sharkey's Lake during periods of free- <br />river and is a portion of the total calculated 663 acre-feet of water stored in the material within the <br />slurry wall lined pit. In 2008, 52 acre-feet was pumped from the Lake for replacement purposes. <br />Approximately 41.1 acre-feet of stored water was returned to the South Platte River during 2009 for <br />replacement purposes. Therefore approximately 253.4 acre-feet of previously booked over water <br />remains within Sharkey's Reservoir as of January 2010. <br />According to the information provided with the SWSP request, Mr. Scott Edgar the water <br />commissioner approved the additional bookover of water into Sharkey's Reservoir since free river <br />conditions existed on the South Platte River main stem last fall. With approximately four months of free <br />river conditions has allowed the Applicant to bookover the remaining 316.5 acre-feet of water in <br />Sharkey's Reservoir (316 acre-feet=663 acre-feet total storage-346.5 acre-feet previously booked <br />over; 316.5 acre-feet/3.53 acre-feet per day=90 days to fill). This result in a total of 569.9 acre-feet of <br />water in storage available for replacement purposes during this SWSP period (253.4 acre-feet after <br />2009 replacement + 316.5 acre-feet booked over in the fall of 2009). <br />The monthly consumptive use and lagged depletions for this plan period are shown in the <br />attached Table 2.