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III. SUMMARY OF CHANGES REQUESTED <br />Coal Mine Waste Banks, 2.05.3(81, and 4.10 <br />The initial waste disposal area site development, including installation of the surface <br />drainage system, was completed in the fall of 2004. The P.E. certification statement that <br />specifically addressed the drainage system installation was dated November 26, 2004. The <br />certification narrative notes that a temporary upper diversion ditch "A" was constructed, as <br />it was not practicable to construct the upper diversion at the final design elevation. The <br />final diversion ditch "A" will be constructed at a later date, when the waste pile surface has <br />achieved an elevation that makes construction of the ditch at the design elevation <br />practicable. The narrative also notes that the upper diversion as constructed would convey <br />the 100 year design flow, with approximately 1.6 feet of freeboard, which was judged by <br />the P.E. to be satisfactory for the temporary ditch. However, the narrative also notes that <br />the permanent ditch design specified a total design depth of 2.9 feet, whereas the <br />temporary upper diversion ditch "A" total depth was approximately 2.0 feet deep. <br />Page 2-12 of the approved permit application, Volume 1, contains the following statement <br />under Diversion Channels. <br />The diversion and co/%ction ditches wi// be constructed according to the design <br />p/ans, with rip-rap if specified, even though they may need to 6e relocated in the <br />future. <br />It appears that the temporary diversion ditch "A" as constructed is adequate to convey the <br />design flow with adequate freeboard, however the temporary ditch does not conform to the <br />final design configuration. <br />Please provide appropriately amended permit tent to allow for temporary ditch dimensions <br />to diverge from permanent ditch design within a specified range (with capacity adequate for <br />design flow plus required freeboardl. In addition, please provide certified "as-built" drawing <br />documentation for any temporary ditches (such as diversion "A") which have not been <br />constructed in accordance with the permanent ditch design plans. <br />6 <br />