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mining begins, all disturbed areas of the permit will drain to the lake itself, with a large volume <br />available for runoff storage and sediment control. <br />Once groundwater is encountered approximately 5-10 feet below the existing surface elevation of <br />4494', a pump will be set in the pit with a gravel berm filter to dewater the mining excavation. The <br />berm will be modified as necessary to ensure that all water pumped is clean and will safisfy NPDES <br />standards. During the first month of pumping, flow rates are expected to be 1500 to 2500 gal/minute <br />and then drop off to 800 gaUminute thereafter. The water will be pumped into the old gravel pond <br />located southwest of the permit on the Rigg property. See Map E-1 for details. The pump will uti- <br />lize a small generator for power. All discharges will be regulated under a combined storm wa- <br />ter/process water permit that has been applied for with the Colorado Department of Health.. If the <br />water quality is out of compliance, water will not be pumped until it is in compliance. <br />4. Mining Timetable <br />Mining of the 9.75 acre disturbed area will last approximately 2 winters, although only 5 months of <br />activity are expected in the winters of each of the two years, depending on equipment, weather and <br />gravel demand. Assuming mining starts in January of 2002, reclamation would be completed by <br />May of 2004, except for seeding, which would be done in late fall of 2004. <br />The following timetable is a best estimate of the sequence of operations for the life of the mine: <br />Task # Description Time Needed <br /> Months <br />1 Strip Topsoil from Phase 1 and Constmct Ditches and 0.1 <br /> Stockpile. <br />2 Strip Overburden from Phase 1 and Construct Ditches and 0.2 <br /> Stockpiles. <br />3 Mine Phase 1 (110,000 tons) and dewater pit area. 3.0 <br />19 Road Pit 10(02 15 <br />