Laserfiche WebLink
Water contained in the sediment pond will not be discharged into the <br />meadow, but allowed to evaporate. The only water to be discharged from <br />the ponds will be from precipitation events approaching or exceeding the <br />ten year, twenty -four hour storm event. The ponds are described in <br />Section 2.05.6 and are designed to manage the precipitation events as <br />required by regulation and in accordance with the requirements of GCC <br />Energy's N.P.D.E.S permit No. CO -G- 850001. <br />PONDS, IMPOUNDMENTS, AND DIVERSIONS <br />DRAINAGE PLAN <br />The drainage plan for the King II Mine will consist of diversion of <br />uncontaminated water originating upstream of the mine yard, through <br />the yard to the discharge point at the south end of site. Runoff <br />generated on the yard itself will be collected and routed through the <br />sedimentation ponds. <br />Refer to 2.05.6 (Hydrologic Balance) Appendix 10 & 11 and Maps King II- <br />007 A thru G for a detailed description of Mine Surface Drainage and <br />Sediment Pond design and descriptions. <br />The sediment control system for the King II Mine will be comprised of <br />undisturbed area drainage ditches and one sediment pond. Designs for <br />sediment control system structures are included in Appendix 11. <br />Approximately 1.3 acres of the disturbed area lies below the <br />sediment pond, consisting of the haul road between County Road 120 <br />and the north end of the Sediment Pond. Runoff from this area will tend <br />to collect and drain along the haul road bypassing the sediment pond. <br />Alternate sediment control measures are to be used in this area. These <br />measures consist of the use of rock check dams, rock filters and gravel <br />surface. This area is too small and too flat to run a SEDCAD <br />demonstration. Therefore, GCC Energy, LLC commits to sampling any <br />discharge from this area for Total Settable Solids. This runoff flows into <br />the area on either side of the haul road. This area will be similar to <br />Small Area Exemption # 1 of the current King I Mine permit, as approved <br />by the Division. <br />UNDISTURBED AREA DRAINAGE DITCHES <br />Two undisturbed area drainage ditches will convey undisturbed surface <br />flow around the disturbed area of the mine surface facilities and return <br />the flow to the native surface drainage channel below the mine bench. <br />The ditches encircle the mine disturbance. One ditch conveys surface <br />flow along the west side of the mine facilities to the native channel, while <br />the corresponding ditch drains east and south above the mine portal and <br />down the east side of the mine bench and surface facilities to the native <br />channel. These open earthen channels will be sized to contain the <br />precipitation events as required by regulation. The channels will be <br />GCC Energy, LLC King II Mine <br />Section 2.05.3 <br />Page 5 March, 2010 <br />