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1.2. Sediment Control Svstem for Gold Operation (This Section revised for TR -10 in January 2015 <br />The sediment control system for the mine, including the water handling system from the River, is shown <br />on Maps C -2 and C -4. <br />The permit area is basically divided into 2 areas, the area north of Access #1 that drains into Ponds 3 and <br />4, and the area south of Access #1 that will drain into constructed South Ponds #1 and #2 which have <br />not yet been constructed as of January 2015. <br />Area North of Access #1 <br />For the northern area, all runoff around the plant and the regraded area will flow into Ponds 3 and 4. <br />These ponds do not discharge. New controls have been put into effect that prevent any discharge from <br />these ponds or any other disturbed area on the site. <br />The water handling system works as follows: Water from the Point of Diversion in the South Platte <br />River is pumped from the Pump House into a 10" PVC Pipe which runs along the north edge of Access <br />Road #1 to a tee located immediately south of Pond #4. The valve on this tee is marked with very large <br />letters showing whether the water from the pump is being delivered to Pond #4 or if it continues directly <br />into the plant. The discharge into Pond #4 is elevated 3.0 feet above the highest level in Pond #4 so that <br />no water can flow back through the pipe into the pump house and back into the River. In addition, a <br />backflow preventer has been installed to prevent this from occurring even if water were to reach the <br />elevation of the pipe. The overflow culvert drains Pond #4 and allows any excess water to drain to the <br />south to the various existing ponds located in the future mining area, which allow the water to infiltrate <br />into the ground. The top of the overflow culvert is located at least 1.0 feet below the invert of the 10" <br />PVC pipe discharge into the Pond, so that water must flow in the overflow culvert before it can enter the <br />10" PVC pipe. In addition to these items, site personnel have been trained in the full operation of the <br />pump, the valves and the plant, as well as the frequency of cleaning out all 4 ponds so that large water <br />volumes are maintained in the ponds to allow sediment to settle out. <br />The other side of the tee in the 10" PVC pipe goes directly into the plant building for the gold washing <br />operation. It is buried along most of the length after the tee. <br />Alma Place Mine 01/15 16 <br />