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EXHIBIT G -WATER INFORMATION <br />This information provided in this Exhibit is intended to satisfy the requirements outlined in Section <br />6.4.7 of the Colorado Mined Land Reclamation Board Construction Material Rules and <br />Regulations: <br />(a) Locate on the map (Exhibit C) tributary water courses, wells, springs, stock water <br />ponds, reservoirs and ditches <br />The Whitney Ditch flows through the project site and the Cache La Poudre River is <br />approximately 1,500 feet to the south. Please refer to Exhibit C for locations of water <br />courses in close proximity to the site, including wells, springs, stock water ponds, reservoirs <br />and ditches. Also attached is a well inventory of surrounding wells plotted from the Colorado <br />State Engineer's Office data base (2000). We have requested updated information from the <br />State Engineer's Office. <br />(b) Identify all known aquifers <br />The Site is underlain by the Cache la Poudre alluvial aquifer. <br />(c) Show how water from dewatering operations or runoff from disturbed areas, piled <br />material and operating surfaces will be managed to protect against pollution of either <br />surface or groundwater both during and after the operation. <br />Please refer to the Mining Plan Map in Exhibit C of this application. Mine areas will drain <br />internally. Uncontrolled releases of surface water in disturbed areas will not occur. <br />Stormwater collected in the active mine area will be managed through the dewatering <br />system. <br />(d) Estimate project water requirements including flow rates and annual volumes for the <br />development, mining and reclamation phases of the project. <br />Projected Use And Consumption: Annual evaporative depletions will be the evaporation <br />from up to 8513 feet of 4-foot wide de-watering trench, located outside of the slurry wall, and <br />an approximately 2.4 acre silt pond, also located outside of the slurry wall. A 3.9-acre fresh <br />water pond will be located inside the slurry wall. The total area of exposed water, including <br />dewatering trenches, the fresh water pond and silt pond, is 7.08 acres. The gross annual <br />pan evaporation at the Long Resource aggregate mine is 55 inches according to NOAH <br />Technical Report NWS 33, Evaporation Atlas for the Contiguous 48 United States (Plate 1). <br />Gross shallow lake evaporation is 70% of the gross annual pan evaporation, or 38.5 inches. <br />Monthly evaporative losses are determined using percentages specified by the State <br />Engineer's Office for locations below 6,300 feet. The nearest weather station is in Greeley <br />where the average annual precipitation is 13.97. Effective precipitation, that part of historical <br />precipitation which was consumed by native vegetation on land to be covered by water <br />surface, is conservatively estimated to be 70 percent of the total precipitation. The annual <br />average effective precipitation at the property is estimated to be 9.78 inches. When <br />subtracting the effective precipitation from the gross evaporation yields, the net annual <br />evaporation is 28.72 inches, or 2.39 acre-feet per acre. The annual amount of evaporation <br />from open water surfaces is 16.93 acre-feet. <br />Hall-Irwin Corporation -Long Resource - MLRB 112 Permit Application <br />Exhibit G -1 <br />