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<br /> <br />J.E. Stover & Associates -18- May 31, 1996 <br />Bowie No. 2 Mine <br />may be true, please perform an appropriate vegetation <br />sampling program in areas outside of the present sampling <br />area. If the results show a difference from the present <br />sampling results, curve numbers may need to be changed. <br />53. The annotation for the gob pile pond needs to be added to <br />Map 21-1, Drainage Plans, and Map 20, Sedimentation Control <br />Plan. <br />54. The outslope of pond A is listed as 1.5H:1V on Map 22-A, <br />Pond A Design. Rule 4.05.6(11)(f) requires that no pond <br />embankment be steeper than 2H:1V without an appropriate <br />demonstration that the slope is stable. on page 2.05-31, <br />pond A is referred to as a dugout pond. However, examination <br />of Section A - A~, on Map 22-A, seems to suggest that an <br />embankment is present. Rule 4.05.9(6) requires that <br />excavated impoundments meet all of the requirements of Rule <br />4.05.9 that apply. Rule 4.05.9(2) requires that all <br />temporary impoundments that have a dam must follow, among <br />other rules, Rule 4.05.6(11)(f) which refers to dam <br />stability demonstrations. <br />If you agree that pond A has an embankment, please provide <br />the appropriate demonstrations that show that the outslope <br />at 1.SH:lV is stable. If you do not agree that pond A has an <br />embankment, please explain why. <br />55. In Volume IV of the permit application, in Appendix B, ditch <br />designs for the coal waste pile are presented. In Appendix <br />C, ditch designs for the coal waste pile are also presented. <br />The ditch designs in both appendices are different from each <br />other. Why are there two different presentations for these <br />ditches and which presentation applies to the in-the-field <br />situation? <br />56. Drawing 95266-04 shows that the side slopes for the runoff <br />control ditches are 2H:1V. However, the ditch designs in <br />Appendix B of Volume IV list 1H:1V for the side slopes for <br />all of the ditches. In Appendix C, the ditch designs for the <br />crest ditch and the upper diversion show side slopes of <br />1H:1V. Please reconcile these differences. <br />57. Drawing 95266-04 shows that the emergency spillway side <br />slopes are 2H:1V. However, the sediment pond spillway <br />worksheet in Appendix C shows side slopes of 1H:1V. Please <br />reconcile this difference. <br />58. In Appendix B of Volume IV, a curve number of 63 is used for <br />basin A3b. However, examination of Map 3, Vegetation, and <br />