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EXHIBIT G <br />Water Information <br />The 25th Avenue site is located in Weld County north and west of the City of Greeley. The 25a' <br />Avenue site will consist of two existing lakes that lie within the current DMG permit boundary <br />for the Greeley West Pit, M-77-081. The Poudre River is located to the north of the site, Figure <br />G-I shows the location of the 25`h Avenue site and the Greeley West Pit. The Greeley West Pit <br />has operated under a substitute supply plan from the State Engineer's Office (SEO) since ]990 <br />without injury to senior water rights. <br />The Greeley West Pit is owned by Flatiron Companies, but leased by Lafarge Corporation for <br />mining. Since the property has been operated as a sand and gravel mine for many yeazs, the 25°i <br />Avenue site does not contain any active irrigation structures that convey water outside of the site <br />boundary. <br />Prior to mining, the 25`h Avenue site will be sealed from the tributary groundwater system by <br />construction of a slurry wall in accordance with SEO Standazds. The slurry wall liner is <br />scheduled for construction in May 2002. Prior to mining, the lined pit will be dewatered to <br />remove the water trapped in the existing lakes when they were sealed by the slurry wall. This <br />will allow the deposit to be dry mined. Water collected will be pumped back to the Poudre <br />River. <br />The mining operation at the 25'h Avenue site will operate inside the slung wall. The slurry wall <br />will be constructed inside the mining permit boundary. The material mined at the site will be <br />processed on-site using portable equipment. The consumptive uses at the 25"' Avenue site will <br />include evaporation, the moisture retained in the mined material, and water used for dust control. <br />Mining of the 25th Avenue site will occur in two mining phases and last approximately 8 years. <br />Reclamation will occur concurrent with mining operations. After reclamation, the site will be <br />used as a lined water storage reservoir for the City's municipal supply. The City of Greeley will <br />complete the process to test and certify the lining of the pit as required in "State Engineer <br />Guidelines for Lining Criteria for Gravel Pits, August 1999. "The SEO certification of this liner <br />will be obtained prior to use of the facility for future water storage. <br />Water Requirements <br />The evaporative losses from exposed water surface azea include the remaining lake area, settling <br />ponds, dewatering trenches, and collection basins. The operational losses from the mining <br />operation include water used for dust control and water retained in the mined product. <br />The NOAA Technical Report NWS 33, Evaporation Atlas for the Cont~ous 48 United States <br />(U.S. Department of Commerce) was used to determine gross evaporation. For this location, the <br />annual evaporation is 45.0 inches. Monthly evaporation percentages as suggested by the Office <br />of the State Engineer were used to calculate monthly evaporation. <br />25'" Avenue Siie <br />DMG 111 Permi! <br />Page !1 <br />