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3) It is not clear whether the undisturbed diversion ditch and the refuse area diversion ditches all share the same design. The design drawings should reference which ditches the design is for. 4) Please indicate how the ditches along the road key in with the ditches diverting runoff from the refuse pile. 5) WFU should indicate in the text and/or on Map 77A whether there is a culvert or low water crossing at the pit to pit dozer access. If not, indicate what measures will be taken to prevent the dozer access from interfering with the ditch. 6) WFU's SEDCAD run assumed sheet flow conditions (Land Use Category 3) for a distance of 4000 feet for the undisturbed drainage. However, according to Dr. Warner, coauthor of SEDCAD, sheet flow conditions should be assumed for a maximum of 400 feet (personal communication with Susan Burgmaier, DMG). WFU should select another appropriate land use category for the portion of the undisturbed flow that is below the uppermost 400 feet. 7) The design for the pond spillways shows a vertical side. WFU should indicate how they intend to ensure the stability of.the spillway, and how the vertical side will be riprapped? 8) WFU should submit plans for maintaining the drainage pattern during the construction of the refuse pile. (4.10.1(1)(a) and 4.09.2(5)). Geotechnical Review 9) The geotechnical review by Lincoln-Devore, submitted by WFU, recommends that the sediment pond be lined with clay and located a minimum of 160 feet from the toe of the refuse pile to ensure the stability of the materials underlying the refuse pile. WFU has located the pond the minimal distance from the toe of the refuse pile but has not indicated that the pond will be lined with clay. WFU should indicate whether they intend to follow their consultant's suggestions. If not, they should indicate what measures will be taken to prevent seepage from the pond. 10) WFU should include a schedule for compaction testing on Refuse Pile 5A.