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Mr. Forrest Leaf <br />March 6, 2006 <br />Page 2 <br />The remaining uses at the site are water lost in mined product and water used for dust <br />suppression. The plan specifies that for 2005, 22.06 acre-feet of water was removed in <br />750,000 tons of mined product and in 2006, 11.77 acre-feet of water will be removed in 400,000 <br />tons of mined product. The water required for dust control is 3.31 acre-feet for both 2005 and <br />2006. <br />The depletions from evaporation, water removed in product and dust suppression were <br />lagged to the stream system using a Glover analysis and assuming the parameters specified in <br />Table 1 below. <br />e <br />Dewatering of the site commenced in October 2003 at a rate of 750 gallons per minute <br />In 2004 dewatering decreased to 350 gallons per minute. All water pumped for dewatering in <br />2003 and 2004 was pumped from the dewatering trench into one of the silt ponds located <br />outside of the slurry wall for recharge back to the river. In September 2004 the dewatering <br />activities within the slurry wall were completed and the lined cell was effectively dewatered. Any <br />residual water remaining within the pit is used for dust suppression. All depletions that result <br />due to evaporation and consumption of the residual water are covered under this plan. The <br />depletions resulting from dewatering pumping and accretion resulting from dewatering recharge <br />were lagged to the stream using a Glover analysis and assuming the parameters specified in <br />Table 1 below. <br />The calculated lagged depletions are based on actual use at the site and account for all <br />past use. Those lagged depletions are shown in attached Table 4. <br />Table 1 <br />Lagged Dealetion W <br />ft T <br />d/ft S X <br />ft <br />Concrete Batching (well no. 60729-F) 2,587 100,000 0.2 1,510 <br />Evaporation, water removed in product and <br />dust su ression <br />2.976 <br />100,000 <br />0.2 <br />715 <br />Dewatering Depletions 2,976 100,000 0.2 715 <br />Dewatering Recharge 2,976 100,000 0.2 771 <br />W- Distance from Stream to No Flow boundary <br />T - Aquifer Transmissivity <br />S -Aquifer Specific Yield <br />X -Distance from well to stream <br />Replacements <br />The proposed source of replacement for this pit is fully consumable water leased from <br />the Town of Milliken ("Milliken") pursuant to excess augmentation credits from Milliken's 2005 <br />and 2006 SWSPs filed under Division 1 Water court case no. 02CW339. The excess credits <br />from Milliken accrue to the Big Thompson River in the same location that the lagged depletions <br />from the Bernhardt Pit impacts the river, therefore, no river conveyance losses will be <br />assessed. <br />h' <br />