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Michael Boulay May 21. 2008 <br />Please include in the sediment pond design installation of an energy <br />dissipater or riprap protection at the outfall of the pipe. <br />CAM: Rip Rap protection will be provided at the outfall of the pipe and is shown <br />on Figure 2.2-3. <br />22. DRMS: It appears that it may be necessary to armor the inlets to the <br />sediment pond given the significant velocities and flow volumes entering the <br />north and east sides of the pond. <br />Please evaluate this concern and amend the sediment pond design <br />information as warranted. <br />CAM: See updated Figure 2.2-3 showing new ditches D-17 & 18 and the <br />location of the rip rap. See new SEDCAD pages 41 and 17 (respectively) <br />showing the design for the ditches and updated Table 2.2-12. Ditch 18 could not <br />be sized by SEDCAD and therefore was designed in Excel using mannings <br />equation, however, the peak flow calculated by SedCad is shown on page 69. <br />23. DRMS: At the base of the D-7, Upland drainage an ephemeral stream is <br />shown flowing into the disturbance area east of the Coal Mine Waste Pile. It <br />appears that this flow should be ditched over to either D-7- 1 or D-7-2 to avoid <br />erosive problems at the upper end of the D-7 drainage basin. <br />Please revise the D-7 ditch design accordingly. <br />CAM: See new ditch D-7-3 as shown on Table 2.2-12 and new various revised <br />SEDCAD pages. <br />Rule 2.05.3(8) Coal Mine Waste and Non-Coal Processing Waste <br />24. DRMS: Various different terms are used in the application text and figures <br />to describe the proposed coal mine waste pile. <br />Please amend the various sections to be consistent, and use "Coal Mine <br />Waste Pile" since coal mine waste is the term defined in the regulations. <br />CAM: "Coal Mine Waste Pile" has replaced GOB in application text and figures. <br />25. DRMS: Page 2-27ii states that the operator does not plan to install an <br />underdrain system beneath the coal mine waste pile, unless "for cause" (i.e. <br />springs or seeps are discovered as the work progresses), referring to an <br />alternate design allowed under Rule 4.09.1(3) and 4.10.3(5). This is an incorrect <br />application of Rule 4.09, which refers instead to Disposal of Excess Spoil <br />("overburden"), and not to Coal Mine Waste. <br />10