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Wash water losses will be incurred from the evaporative losses in the plant and the sediment ponds. There will be three cells to the ponds with a total exposed acreage of approximately 0.7 acres. The net evaporation from the ponds would require 2.5 acre-feet of replacement water. Minor losses through the plant that did not recharge the groundwater would probably account for an additional 0.5 acre-feet which would increase total wash water consumptive use to 3.0 acre-feet. Dust Coatrol There are approximately 1,950 linear feet of haul road that will be constructed on the property. This road will be watered during the spring, summer, and fall seasons when required as part of the Colorado Department of Health APEN. It is estimated the road will be watered approximately two times per day on the average using a water truck with spray heads. The application rate is approximately 1/8 inch per square foot. This equates to 0.02 acre-feet per day for a 24 foot wide road of this length. The average season will be approximately 140 days per year. The estimated total water consumption for dust control is calculated to be 3.1 acre-feet per year. Moisture Loss is Materials The proposed mining operation will excavate at a maximum between 200,000 to 300,000 tons of material per year. The average material moisture content for stockpiles has been calculated to be 4B from a City and County of Denver study. This study has been used in the approval of mining permits in the past across the state and is assumed to be reasonable. If the maximum amount of material is moved, a 48 water content equates to 8.83 acre-feet. Evaporative Loss from Lakes The net evaporative loss for a reservoir located in the Greeley area would be in the range of 2.5 acre-feet per acre. Assuming minimal credit for historic consumptive use of vegetation, this would equate to allowing 54 acres of lake surface to be exposed. At present, the operator is planning on a project larger than this size which indicates that at the end of mining additional water for covering evaporative uses is needed. The: evaporative loss from the reservoir would only occur after the project has been mined, reclamation has been completed, and the dewatering activities have been suspended. Therefore, these evaporative losses will not be incurred during mining. The owner has committed to acquiring additional rights to cover any lake exposure proposed that is larger than 54 acres. G-4