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Please amend Figure 2.2-3 to show riprap locations. <br />30. Table 4.2-13 Culvert and Ditch Sizing Calculations - The Table lists Design <br />Points L, M, N, and O. These points do not appear on Figure 2.2-3. <br />Please amend Figure 2.2-3 to identify the referenced design points. <br />31. Division aerial photos of the site show the existence of a fence beginning across <br />McClane Creek, due south of the office area, and extending southeast to the <br />southern limit of the proposed Coal Mine Waste pile. This fence does not appear <br />on Figure 2.2-2. The fence will likely need to be reconstructed on a new <br />alignment to the south of the proposed new area of disturbance. <br />Please address the use and state of repair of this fence, and whether <br />relocation or removal of the fence during the period of mining operations will <br />impact surface owner management plans. <br />32. Section D-D' of Figure 2.2-3 depicts the original and proposed ground surfaces. <br />It does not depict the depth of excavation of native material (topsoil and subsoil) <br />that will be performed. This information will be a critical component for <br />evaluation of any subdrainage system proposed for the pile. <br />Please address depth of excavation in the appropriate narrative sections of <br />the application, and provide an amended section D-D' that depicts original <br />and excavated ground elevations. <br />33. Two separate drainage basins are labeled as "D-6" on Figure 2.2-3. <br />Please revise the drainage basin labels on Figure 2.2-3 as appropriate. <br />34. For analysis of material that will comprise the Coal Mine Waste pile, the <br />geotechnical consultant had access to only a small stockpile from which to collect <br />samples. Consequently, the stability analyses conducted may not represent the <br />potential variability in coal mine waste that may occur as the pile is constructed. <br />In order to validate the findings and factors of safety reported, additional testing <br />of physical properties should be conducted from the additional volumes of waste <br />that have accumulated subsequent to the original sampling. If these test results <br />[i.e. gradations, Atterberg limits, and moisture/density (Proctor) curves] bear <br />close resemblance to those achieved for the original samples collected, then no <br />additional testing and analysis may be warranted. However, if it becomes <br />apparent that the coal mine waste is quite variable in composition, further <br />analyses may be required. <br />Please obtain additional samples from the mine bench and sediment storage <br />stockpiles, and from pond and ditch sediments, with separate samples for <br />10