2007-09-11_REVISION - M1997054 (2)

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EXHIBIT G ~/ Water Information The mining operation is located in the Sections 11, 12, 13, and 14, Township 18 South, Range 72 West, Sixth P.M. in Fremont County. The Pazkdale Project site is approximately 10 miles west of Canon City on the north bank of the Arkansas River, The operation consists of sand and gravel production, as well as a granite quarry operation. Impacts may occur to the Arkansas River in the form of depletions due to evaporation and operational losses including water used for dust control and water retained in product hauled off site. Mining will continue in this area for approximately 8-12 yeazs for the gravel operation and approximately 50-60 years for the quarry operation. The mining operation will extract sand and gravel deposits from the Arkansas River aquifer and will impact groundwater systems hydraulically connected to the Arkansas River. Monitoring well drilling has found 20 feet to more than 40 feet of gravel above the water table or bedrock and 17 Feet to more than 36 feet of gravel and sand below the water table elevation. For detailed information relating to groundwater impacts, see attached groundwater modeling study. Depletions will result from three settling ponds, a gravel washing pond, dust control of haul roads, and retained water in material transported off-site. To enable dry mining at the site, dewatering trenches will be constructed around the perimeter of the pit. Groundwater and storm water will flow along trenches and surface flow by gravity to collection basins. While mining is active, the exposed water surface will be approximately 1.6 acres, including 0.5 acres for settling ponds, 0.1 acres for a gravel washing pond, and approximately 1 acre for exposed groundwater in the dewatering trenches on site. WATER REQUIREMENTS The annual consumptive use at this site during the mining operation is estimated at 43.63 acre- feet and will result from evaporative losses and operational losses. Evaporative losses are dependent on the exposed water surface area, which may vary throughout the mining operation. Evaporative Consumptive Use Total annual evaporative loss is the product of net annual evaporation and total exposed groundwater surface azea. The maximum exposed surface area at the site during mining is estimated at 1.6 acres. The NOAA Technical Report NWS 33, Evaporation Atlas for the Contiguous 48 United States (U.S. Department of Commerce) was used to determine the gross evaporative loss of 46 inches. Monthly evaporation percentages as suggested by the Office of the State Engineer were used to calculate monthly evaporation. Annual precipitation was determined using Western Regional Climate Center website (www.wrcc.dri.edu) data for the nearest station, Canon City (# 51294). The average annual precipitation of 12.83 inches was used to calculated evaporative consumptive use at the site. Effective precipitation was calculated as 70% of the total precipitation, or 0.75 feet. The net annual evaporation, the difference between the gross and effective precipitation, is approximately 3.08 acre-feet per acre, resulting annual evaporative consumptive use during the mining operation is 4.96 acre-feet. Front Rartge Aggregates, LLC- Parkdale Quarry DMG !72 Permit Amendment Page 15