2015-04-03_PERMIT FILE - C1981041 (4)

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Roadside North Portal Final contours for the Roadside North Portal area are shown on Exhibit 8C. Cross - sections representing the existing and final grade are shown on Exhibit 27. These final contours closely resemble the original contours, see Exhibit 8D for the pre- mining contours. During 2002 this area was regraded to approximate original contour. Backfill material came from areas filled near Coal Creek and around the stockpile area. There was no coal remaining in the stockpile. Dirt and rock placed in the decline was spread in approximately 2-4' lifts in such a way as to minimize voids in the fill. There were no specific compaction requirements. Lifts were basically spread in horizontal layers and hauling equipment was routed over the fill to provide compaction. The small amount of settling that will take place with this fill technique will have little affect on the final contours and drainage. Concrete and other material left after demolition of the facilities was placed in the fill material. Topsoil pile 3 and a portion of Topsoil pile 1 was distributed over the regraded site. The majority of Topsoil pile 2 was also used in the 2002 reclamation project. The small remnant of Topsoil Pile 2, as depicted on Exhibit 8C, will remain as part of the final contours. There are currently 7 guy wire anchors, which support three transmission power poles, buried in the remnant of Topsoil Pile 2. As there is adequate volume of material remaining in Topsoil Pile 1 to complete reclamation at Roadside North and South disturbed areas, the small volume left in Topsoil Pile 2 is unnecessary for final reclamation and the cost of relocating the guy wires and /or poles in order to retrieve this material is not economically feasible. The small berm at the toe of Topsoil Pile 2 will be removed and graded so that no impounding of water will occur and the drainage will flow around the toe toward Coal Creek. The remnant of Topsoil Pile 2 is stable, well vegetated and blends into the surrounding terrain. The sediment pond shown on Exhibit 8B was utilized for sediment control at the North portal. A grass filter design is presented in Appendix 14 -6 beginning on page 147. The grass filter design demonstrates the silt fence, previously shown on 86, is no longer required. Demonstration that disturbed area sediment controls are no longer necessary at the North Portal is presented in Appendix 14 -13. Upon approval of PR -5, Pond 13 will be backfilled. The small berms running along Coal Creek and ditch D10, as depicted on Exhibit 8C, are stable and well vegetated and will remain intact as permanent features. Also, the West Diversion Ditch and East Diversion Ditch, with slight modifications, will remain as permanent features as depicted on Exhibit 8C. The East Diversion Ditch will be divided into two sections. Ditches designed to carry the flows from storm runoff from the drainage above the slopes of the disturbed area will be constructed as depicted on Exhibit 8C. The existing concrete headwall and 36" CMP flume at the end of the East Diversion Ditch will be removed and the area will be backfilled and seeded. The design of the ditches is presented in Appendix 14 -6. The East and West Diversion ditches are stabilized with well established vegetation and have been constructed to meet the requirements of Rule 4.05.3 (see Appendix 14 -6, pages A14 -6 -127 through A14 -6 -131). If the existing East and West Diversion ditches were required to be reclaimed and replaced by the new construction of multiple ditches, as depicted in previous approvals, over 2 acres of well established vegetation would be re- disturbed unnecessarily. Land owner consent is presented as Appendix pages A14 -5- 42 and A14 -5-43. PR -5 14 -10 (Rev 05/12)