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<br />Please reconcile these differences. <br />34. Drawing 95266-04 shows that the emergency spillway side slopes <br />are 2H:iV. However, the sediment pond spillway worksheet in <br />Appendix C shows side slopes of 1H:1V. Please reconcile this <br />difference. <br />35. In Appendix B of Volume IV, a curve number of 63 is used for <br />basin A3b. However, examination of Map 3, Vegetation, and Map <br />20, Sedimentation Control Plan, suggest a larger curve number <br />may be appropriate. It appears that the drainage basin for A3b <br />is composed of about 75$ disturbed area and about 25$ burned <br />area. Using a curve number of 89 for the disturbed area and 65 <br />for the burned area, an average curve number of about 83 would <br />seem appropriate. Please justify a curve number of 63 for <br />basin A3b. <br />36. The construction of the underdrain for the coal waste pile <br />does not mention the use of a filter blanket over the rock <br />underdrain, to add further protection from clogging. Please <br />comment on this. <br />37. The coal waste pile topsoil pile and coverfill stockpile need <br />to be added to Map 21-1, Drainage Plans, and Map 20, <br />Sedimentation Control Plan. <br />38. On page 2.04-36, it is stated that mining will not impact <br />a surface source of water. Please comment on the possibility <br />of subsidence impacting water flow in Terror Creek and Hubbard <br />Creek. <br />39. Rules 2.04.7(2)(a) and (b) require surface water quantity data <br />for streams in the permit area and adjacent area. Page 2.04-33 <br />lists flow data for Hubbard Creek. Please provide flow data <br />for Terror Creek. <br />40. Rules 2.04.7(2)(a) and (b) require specific surface water <br />quality data for those streams receiving discharges from <br />affected areas within the permit area. Since springs that may <br />be affected by mining flow into Terror Creek and Hubbard <br />Creek, please submit surface water quality data for those two <br />streams. <br />2.05.6 MZTIGATION OF THE IMPACTS OF MINING OPERATIONS <br />41. On page 2.05-64 of the permit application, speed limits of 20 <br />to 30 mph are stated. The Division wishes to add that there <br />may be further limitations on speeds due to fugitive dust <br />potential. The fugitive dust air emissions permit will state <br />such limitations, if any. <br />7 <br />