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EXHIBIT G <br />Water Information <br />Introduction <br />The proposed mining operation is located in the Northeast corner of Section 24, Township 6 <br />North, Range 68 West, Sixth P.M. in Larimer County. The proposed SerFer Pit mining site is <br />located between the north bank of the Cache la Poudre River and State Highway 392 and just <br />west of County Road 13. The Cache la Poudre River runs along the southern boundary, State <br />Highway 392 runs along the northern boundary and County Road 13 runs along the eastern <br />boundary of the site. The operation will consist of sand and gravel production and will impact <br />the Cache la Poudre River in the form of depletions due to evaporation and operational losses <br />associated with mining. Mining of the SerFer Pit will last for approximately 3.5 years. Once <br />reclamation is complete, a lined reservoir will be created and will have a total surface area of <br />approximately 20 acres. <br />The mining operation will extract sand and gravel deposits from the Cache la Poudre River <br />aquifer and will impact groundwater systems hydraulically connected to the Cache la Poudre <br />River. The depth to groundwater ranges from 3 to 4 feet. <br />Depletions will result from two settling ponds, dust control of haul roads, and retained water in <br />material transported off-site. To enable dry mining at the site, dewatering trenches will be <br />constructed around half of the perimeter of the pit. Water from the dewatering trenches will be <br />discharged into the settling ponds. While mining is active, the exposed water surface will be <br />approximately 0.49 acres, including 0.09 acres for settling ponds and approximately 0.4 acres for <br />exposed groundwater in the dewatering trenches on site. <br />The entire mining site lies within the Cache la Poudre River 100-year floodplain. All work <br />performed in the floodplain will conform to the Larimer County Flood Hazard Regulations. <br />Water Requirements <br />The annual consumptive use at this site during the mining operation is estimated at 9.2 acre-feet <br />and will result from evaporative losses and operational losses. Evaporative losses are dependent <br />on the exposed water surface area, which may vary throughout the mining operation. <br />Evaporative Consumptive Use <br />Total annual evaporative loss is the product of net annual evaporation and total exposed <br />groundwater surface area. The maximum exposed surface area at the site during mining is <br />estimated at 0.49 acres. The NOAA Technical Report NWS 33, Evaporation Atlas for the <br />Contiguous 48 United States (U.S. Department of Commerce) was used to determine the gross <br />evaporative loss of 40 inches. Monthly evaporation percentages as suggested by the Office of <br />the State Engineer were used to calculate monthly evaporation. <br />Annual precipitation was determined using World Climate website (www.worldclimate.com) <br />data for the Windsor station. The average annual precipitation (from 1941 to 1990) of 12.5 <br />SerFer Project <br />DRMS 112 Permit <br />Page I1 <br />