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\ Chapter IV <br /> All sediment ponds wil be examined quarterly by the company, and <br /> the reports will be submitted to the Division, for the following: <br /> - Seepage from the downside side of the embankment. <br /> - Erosion of embankment slopes. <br /> - obstructions to emergency and/or principal spillways. <br /> - Properly cleaned and maintained dewatering devices. <br /> - Sediment storage volume. <br /> - Sloughing, tension cracks, piping, etc. <br /> Sedimentation ponds will be removed after disturbed areas have been <br /> restored and revegetated, following mine closure, in accordance <br /> with the post-mine reclamation plan. Each pond will be removed, <br /> unless approved for retention as part of the post mining land use, <br /> and the area disturbed by the pond will be regraded, topsoiled and <br /> revegetated. <br /> Reclamation of sedimentation ponds will be accomplished following <br /> mine abandonment, although ponds approved for retention in support <br /> of the post mine land use plan will remain. They will be removed <br /> after the disturbed areas have been restored and revegetated in <br /> accordance with the post mine reclamation plan. The reclamation of <br /> the ponds wil be accomplished when the drainages meet applicable <br /> water quality standards. When the sedimentation pond is removed, <br /> the disturbed area will be regraded, topsoiled and revegetated. <br /> Small Area exemptions have been approved for the following areas: <br /> Southeast corner of the Mine No. 4 bench. <br /> Mine No. 3 lower coal storage pad. <br /> Mine No. 3 upper storage pad <br /> Mine No. 3 lower coal storage bin pad <br /> Mine No. 1 powder magazine <br /> Mine No. 4 powder magazine <br /> Adit/Rock Tunnel Area powder magazine <br /> 7. Discharge Standards. <br /> The sedimentation ponds have been designed to provide a minimum <br /> sediment storage of 0.1 acre feet of sediment per acre of disturbed <br /> land, or designed to contain the 3 year sediment storage from the <br /> disturbed area using the Universal Soil Loss Equation (USLE) . The <br /> designed retention time of the ponds is 24 hours, with dewatering <br /> devices of either a valve activated or T-culvert discharge system <br /> or unlined impoundment natural filtration. <br /> 20 Revised 6/91 <br />