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-z- <br />Rule 4.05.9 requires that, for permanent impoundments; "the level of <br />water shall be sufficiently stable to support the intended use"; <br />"adequate access to impounded water shall be provided"; and design and <br />construction shall be as specified in SC5 publication '378, "Ponds". <br />SCS publication 378 states that small stock ponds and erosion control <br />dams are permitted only on "water courses; the channels of which are <br />normally dry". It further specifies that "the drainage area shall be <br />large enouyh so that surface runoff will maintain an adequate supply of <br />water in the pond. Ramps are to be provided to the anticipated low water <br />elevation at a slope no steeper than 4:1 to allow safe access". <br />Sediment ponds at pits 1, 2, 3, and 4 obviously are not constructed in <br />ephemeral water courses, and following final reclamation and backfilling <br />of collection ditches it is questionable whether surface runoff would <br />maintain an adequate supply of water in the pond. The proposed sediment <br />pond at pit 8 is within 400 feet of an existing stock pond. <br />1. The applicant should provide a discussion demonstrating that the <br />use of water from these impoundments would be in compliance with <br />State Law. <br />2. For each pond to be left as a permanent impoundment, the applicant <br />must provide a detailed design plan prepared by, or under the <br />direction of, and certified by a qualified registered professional <br />engineer. The plan must show that the pond would meet the <br />appropriate design standards of Rule 4.U5.9(1)(e), and that any <br />permanent diversions associated with the pond would meet the <br />standards of Rule 4.05.3. The plan should specifically identify <br />any renovation required to convert the sediment pond or ditches to <br />the standards for permanent impoundments and ditches. <br />3. For each permanent impoundment, the applicant should provide <br />sufficient hydrologic analysis to show that water levels would be <br />sufficiently stable to support their intended use. It is <br />uncertain if stack ponds located high on the hillsides would <br />receive sufficient runoff to accumulate water. <br />4. The water quality for ponds receiving only surface runoff should <br />be sufficient for stock water use. However, ponds receiving water <br />that has passed through the spoil nay not have a suitable water <br />quality. For any permanent impoundment that would receive spoil <br />water (either becuase the pond is in contact with the bottom of <br />the pit and would receive unsaturated flow or because the spoil <br />would develop an aquifer and the pond would intersect the <br />post-mininy spoil water levels), the applicant should provide <br />water quality predictions demonstrating the suitability of the <br />water for stock water use. <br />