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EXHIBIT G <br />Water Information <br />The Platte Valley Pit is located in Sections 30 and 31, Township 1 North, Range 66 West in <br />Weld County. The site is located north of Brighton, west of Highway 85, and east of the South <br />Platte River. Depletions from the South Platte River as a result of the sand and gravel operation <br />will be due to evaporation and operational losses associated with mining. These depletions can <br />be mitigated without injury to the vested senior rights downstream of the site. <br />The reclamation plan for the site calls for the creation of groundwater lakes, wetland areas, and <br />backfilling of the pits created during the mining of the site. Reclamation of the site will proceed <br />concurrent with the mining operation. A substitute supply plan for the replacement of stream <br />depletions during the mining phase is currently in place with the State Engineer's Office. The <br />length of time for the completion of the project is estimated at 2 years <br />Water iJse <br />Water use at the site includes evaporation from exposed groundwater, water retained in material <br />removed from the site, and water for dust control. The exposed groundwater is the result of <br />settling ponds and dewatering trenches constructed to enable dry mining at the site. The <br />maximum exposed surface area during mining is estimated at 6.75 acres. After mining at the site <br />has been completed, the pit will be allowed to fill with groundwater during reclamation of the <br />site. The maximum surface area of the exposed groundwater is estimated at 100 acres. <br />The NOAA Technical Report NWS 33, Eveoration Atlas for the Contiguous 48 States (U.S. <br />Department of Commerce) was used to determine gross evaporation. For this location, the <br />annual evaporation is 42 inches. <br />Precipitation was estimated from the High Plains Regional Climate Center for the Brighton <br />Weather Station. Annual precipitation at the site was assumed to be equal to the Brighton <br />Station, which is 14.55 inches. Effective precipitation was calculated as 70% of the total <br />precipitation. Net evaporation was then computed as the difference between gross evaporation <br />and effective precipitation. The net annual evaporation at the site is 31.81 inches or 2.65 feet. <br />Thus, the resulting net annual evaporative consumptive use during the mining operation is 17.89 <br />acre-feet. <br />Following extraction, the raw material will be processed and hauled off-site for use. The water <br />retained in this material is considered as a consumptive use. The anticipated amount of raw <br />material that will be mined and washed from the site each year is estimated at 1,000,000 tons. <br />Assuming 4 percent moisture content by weight as suggested by the State Engineer's Office, the <br />total annual depletion due to water retained in product is 29.43 acre-feet. <br />In addition, water use at the site will include dust control. From previous experience in mining <br />operations similar to this one, a reasonable estimation of dust control water usage is 2.0 acre-feet <br />per year. <br />Plate Palley Operadian <br />OMG 112 PermitAmendment <br />Page 74 <br />