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4.4.2.8 Mine, Shaft and Drill Hole Closures <br />The closure of the mine portals has been carried out in the compliance with all relevant <br />local, State, DMG and Federal regulations in force at this time. The design shown in <br />Figure 4.4-1 and 4.4-2, specifically designed for the portals #1 and #2, respectively, has <br />been followed. A minor variation of the plans, replacing the concrete block walls with <br />solid concrete walls, has been approved by MSHA. <br />It is part of this plan not only to adequately secure the tunnels and keep them safe in <br />the long term, but also to recontour and vegetate the areas around them to return them <br />to approximately their original contours. At both portals, the natural contours divert <br />water away from the portal openings. In particular for portal #1, the natural ridge from <br />above the portal has been extended. The extension was designed so that any run-off <br />will be channeled approximately 50 feet to the west of the portal opening. No special <br />diversion structure is necessary as the actual construction dimensions by far exceed <br />the minimum design requirements see discussion of page 4-57, Exhibit 4.7-1 and <br />Figure 4.7-3. Both portals have been sealed according to the approved plans. <br />Some of the waste rock from the tunnel excavation was placed back inside the tunnels, <br />between the two concrete walls, one 25 feet inside the tunnel, the other one at the <br />surface opening. Remaining waste material at benches and in front of the portals has <br />been sloped and covered with a minimum 16 inches of topsoil. <br />• All remaining water monitoring wells have been plugged according to state regulations. <br />At a minimum the casing was pulled, if possible, and the hole filled within a few feet of <br />the surface with a bentonite grout. The upper portion of the holes were backfilled with <br />soil. In the case of the horizontal hole SK-3H, the packer was pulled and the hole filled <br />with bentonite grout. The outer three feet were filled with concrete. <br />4.4.2.9 Backfill and Grading <br />The post-mining final graded slopes approximate the general nature of the pre- <br />development topography. The slopes around the portals are nearly the same as those <br />of the pre-mining condition. The areas further downslope from the portal were terraced. <br />As discussed earlier, the flat terrace configuration will keep run-off to a minimum and <br />benefit vegetation through diminished erosion and better water retention. The terraces <br />also promote livestock and wildlife feeding. The roads and terraces will also facilitate <br />the access to the individual areas. <br />The post-mining final graded slopes promote a higher and better use of the land for the <br />pasturing, grazing, and watering of livestock, the cropping, cultivation, and harvesting of <br />plants and wildlife grazing. <br />• <br />NCIG -Coal Ridge No. 1 4-61 5/06 <br />