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Exhibit C -Water <br />Negotiations are pending for acquisition of an adequate substitute water supply. Currently, the <br />total exposed lake surface for the three existing pits at Worthing Pit is approximately 57 acres. <br />The pre-1981 total exposed lake surface area at the amended permit area was approximately 28 <br />acres. <br />Under this amendment, the post-mining land use for the Worthing Pit will include two remaining <br />lakes totaling approximately 57 acres. After reclamation of the Expansion Area North, the <br />existing 3.6-acre lake will be backfilled and no groundwater will be exposed to evaporation. <br />Should a liner be constructed to isolate the WSF from groundwater, a permanent plan of water <br />augmentation will not be necessary. After installation of the liner, there will be no evaporative <br />loss of groundwater associated with the WSF and the total surface area of the remaining lakes <br />will be less than the exposed lake surface area prior to 1981. <br />A well permit from the State Engineer's Office will be required for the gravel pit in the <br />Expansion Area North. As part of the permitting process, the State Engineer's Office will assess <br />the potential impacts of the proposed project to nearby wells within 600 feet of the gravel pit. The <br />applicant will comply with all the conditions and requirements of the Gravel Pit Well Permit and <br />will make every effort to mitigate impacts to neighboring wells. There are no shallow wells <br />within 600 feet of the area to be dewatered for dry mining in the Expansion Area North. <br />Water Discharge Permit <br />Dewatering water will be routed to the settling basin and then discharged to the South Platte <br />River under existing Colorado Discharge Permit System (CDPS) Permit No. COG-500233. The <br />existing discharge permit will be updated to include the mine Expansion Area. A SWMP was <br />previously prepared for the Worthing Pit and will be updated to include the mine Expansion Area. <br />REFERENCES <br />Bishop-Brogden Associates, Inc. 1990. Albert Frei & Sons, Inc. Sand and Grave] Operations, <br />Seuate Bil] 120 Compliance. Submitted to Colorado State Engineer's Office July 13, 2000. <br />Camp Dresser & McKee, Inc. (CDM) 2001. Major Drainageway Planning South Platte River in <br />Adams County, Colorado, Phase B Report. Prepared for Urban Drainage and Flood Control <br />District, Adams County, City of Brighton, City of Commerce City, Denver Water Department, <br />Metro Wastewater Reclamation District, City of Thornton, and South Adams County Water and <br />Sanitation. <br />Colorado State Engineer 2005. General Guidelines for Substitute Water Supply Plans for Sand <br />and Gravel Pits Submitted to the State Engineer, Pursuant to SB 89-120 & SB93-260. [Web <br />Page]. Located at: http://waterstate.co.us/surfacewater/gravelpits.pdf. Accessed: March 14, <br />2005. <br />Kiowa Engineering Corporation 2004. Second Creek (Downstream of DIA) and DFA 0053 <br />Watersheds, Outfall Systems Planning Update, Preliminary Design Report. Prepared for City of <br />Brighton, Commerce City, Adams County, and Urban Drainage and Flood Control District. <br />U.S. Department of Commerce, National Oceanic and Atmospheric Administration (NOAA) <br />1982. Evaporation from Shallow Lakes in Colorado, Annual 1956 to 1970. Evaporative Atlas for <br />the Contiguous 48 United States, NOAA Technical Report NW S 33, Washington, D.C. <br />1898-Frei ll2 Eshibits_(420.05).doc G-Il <br />