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Mr. Jim Stover, P.E. <br />July 16, 2008 <br />Page 4 <br />Rule 2.05.3(4) requires a detailed design plan be submitted for each sediment <br />pond and more specifically 2.05.3(4)(a)(ii)(C) requires that the operation and <br />maintenance of each structure be described. Please clarify the discrepancies <br />described above and provide revised design information which clearly <br />demonstrates how the pond will be operated in compliance with 4.05.2(7), <br />4.05.6, and 4.05.9. In accordance with 2.05.3(4) provide a description of the <br />operation and maintenance of the new pond and incorporate this description <br />into the permit document. <br />20. through 23. Items Resolved. <br />Rule 2.05.3(8) Coal Mine Waste and Non-Coal Processing Waste <br />24. There are still some inconsistencies with the use of terminology for the "Coal <br />Mine Waste Pile". Page 2-34 makes several references to "refuse pile" and the <br />second full paragraph on page 2-27iii refers to the "waste rock disposal area". If <br />appropriate please replace these references with "Coal Mine Waste Pile". <br />25. through 31. Items Resolved. <br />32. Excavation of the subsoil, as illustrated in Section D-D' will result in the creation <br />of a basin approximately six feet in depth. The occurrence of a sizable <br />precipitation event prior to the basin being completely filled with coal mine waste <br />may result in the collection of water, which could saturate the soils at the floor of <br />the basin, or any coal mine waste that has already been placed within it. <br />Please address the anticipated effect upon the stability of the coal mine waste <br />pile foundation, should such an event occur, or explain what would prevent <br />this scenario from developing (e.g. the permeability of the surrounding in <br />situ soils may be great enough to prevent retention of water in the basin). <br />33. Item Resolved. <br />34. CAM's response indicates that an additional stability analysis would be conducted <br />after five feet of material had been placed in the coal mine waste pile. Please <br />clarify the intent of this proposal: does it refer to five feet above the <br />surrounding native ground, or to the first five feet placed in the sub- <br />excavated basin shown on Section D-D'. <br />35. The Division requested further waste pile design detail to specify how drainage <br />requirements would be maintained during interim stages of waste pile <br />construction (to divert runoff from above the pile and from the pile surface to <br />stabilized drainages off the fill, prevent runoff from being directed over the <br />outslope, and to prevent ponding on the fill). Amended text on page 2-27iii, and <br />notation on amended Figure 2.2-3 (Section D-D') addressed interim grading to <br />avoid runoff over the face and ponding on the surface of the pile. The apparent