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Mr. Jim Stover, P.E. <br />September 19, 2008 Page 2 <br />7. through 10. Items Resolved. <br />Rule 2.05.3(3)(c) Description of Roads. Conveyors, or Rail Systems <br />11. through 13. Items Resolved. <br />Rule 2 05 3(4) Ponds Impoundments Other Treatment Facilities and Diversions <br />14. through 18. Items Resolved. <br />19. CAM has updated the permit text and Figure 2.2-3 to demonstrate how the <br />proposed sediment pond will be operated. This portion of the response is <br />acceptable. In CAM's response they also propose removing the Elevation- <br />Capacity-Discharge table from the SEDCAD demonstration and replacing it with <br />a spreadsheet to show the designed capacity of the sediment pond, location of the <br />spillways, and demonstrate that the pond will adequately contain the 10-year <br />event. Two critical pieces of information are missing from the revised <br />demonstration. <br />To comply with Rules 4.05.9(2)(b) and 4.05.9(7)(d), CAM must show the peak <br />stage of water in the pond resulting from the 10-year 24-hour precipitation event <br />and the elevation of the water surface with the emergency spillway flowing at <br />design depth during the 25-year precipitation event. There shall be no outflow <br />through the emergency spillway during the passage of the runoff resulting from <br />the 10-year event [4.05.9(2)(b)] and the minimum elevation of the top of the <br />settled embankment shall be 1.0 foot above the water surface in the pond with the <br />emergency spillway flowing at design depth [4.05.9(7)(d)]. Please revise the <br />spreadsheet demonstration accordingly. Alternatively, CAM could retain the <br />original Elevation-Capacity-Discharge table from the 10-year SEDCAD <br />demonstration and update it with the corrected spillway elevations and the <br />top of sediment storage elevation and provide a revised 25-yearaSEDCAD <br />run showing the peak stage on an Elevation-Capacity-Discharge table. <br />20. through 23. Items Resolved. <br />Rule 2 05 3(8) Coal Mine Waste and Non-Coal Processing, Waste <br />24. through 33. Items resolved. <br />34. CAM's response is acceptable; however, the revised text (in the third to last <br />paragraph on page 2-27i) needs further clarification. Please edit the text added <br />to page 2-27i, for clarity and state that CAM will perform another stability <br />analysis after 5 feet total of material is placed in the over-excavated founding <br />of the pile in order to get a representative sample for analysis.