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Page 2 of 3 <br />6. The ditch D49 SEDCAD printout is unclear. In the time of concentration details (page EXH <br />19(22) -49), there are two times listed for SWS #2 for Structure 92: 0.055 hour and 0.377 <br />hour. Please explain. It would be very useful (but not necessary) to provide a schematic <br />and /or map showing structures, sub - watersheds, and flow paths for D49 and other ditches. <br />7. The location where ditch D49 would originate was inspected. Please provide more <br />details on the design of the upper end of this ditch to determine if it is sufficient to <br />prevent flow down the drainage from impacting the proposed DWDA. Additionally, it <br />appears that the proposed location of ditch D49 pre- disturbance goes up- gradient at the <br />upper section. Does NECC plan on cutting the slope back or cutting the ditch deep <br />enough to allow flow down the drainage and into ditch D49? <br />8. During the Division's May 1, 2012 inspection, it was observed that access roads may be <br />needed to perform maintenance on ditch D49 and ditches along the western end of the <br />proposed West DWDA. Please add access roads or provide an explanation as to why <br />roads will not be needed to perform maintenance on these ditches. <br />9. The proposed roads on Map 14 in TR -65 require clarification. In particular, the roads <br />needed to build the proposed DWDA and the Soil Storage Stockpile may have to be <br />altered from the submitted map. It is unclear how these features will be constructed. <br />10. Please connect ditch D28 to ditch D31 or explain why ditch D28 flows to Containment <br />91, where it is co- mingled with runoff from disturbed areas. Perhaps ditch D28 should be <br />connected to ditch D34b. <br />11. There appear to be errors on Map 14 West Portal Sediment and Surface Water Control <br />Plan regarding ditches D34a and D34b. Should these ditches be extended west to the road <br />intersections north of the West Portal Fan? Please provide an updated map correcting <br />these ditches or an explanation regarding their locations and why ditch D34b would <br />connect to ditch D52. <br />12. Please advise how potential subsidence, and impacts on Containment #2, will be <br />addressed (see Rule 2.053(4)(a)(i)D)). In addition to inspections of the pond, will this <br />area be included in subsidence surveys? <br />13. As per Mr. Ron Gehrke's email, MSHA cannot approve refuse piles over abandoned <br />openings. Please provide discussion of NECC plans to address the Allen Mine portal <br />opening in order to gain approval from MSHA to construct the proposed West DWDA. <br />14. The Division has calculated a bond estimate required to regrade and seed the West DWDA <br />footprint. The cost estimate calculated by the Division totals $70,551.08 (see attached cost <br />estimate) compared to NECC's cost estimate of $104,253.16. The Division's estimate is <br />consistent with previous cost estimates approved by both the Division and NECC. If NECC <br />wishes to use the cost estimate calculated by the Division, please submit a revised estimate <br />that matches the estimate calculated by the Division. <br />