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• regulations in force at this time. The design shown in Figure <br />4.4-1 and 4.4-2, specifically designed for the portals #1 and <br />#2, respectively, has been followed. A minor variation of the <br />plans, replacing the concrete block walls with solid concrete <br />walls, has been approved by MSHA. <br />It is part of this plan not only to adequately secure the <br />tunnels and keep them safe in the long term, but also to <br />recontour and vegetate the areas around them to return them to <br />approximately their original contours. At both portals, the <br />natural contours divert water away from the portal openings. In <br />particular for portal #1, the natural ridge from above the <br />portal has been extended. The extension was designed so that any <br />run-off will be channeled approximately 50 feet to the west of <br />the portal opening. No special diversion structure is necessary <br />as the actual construction dimensions by far exceed the minimum <br />design requirements see discussion of page 4-57, Exhibit 4.7-1 <br />and Figure 4.7-3. Both portals have been sealed according to <br />the approved plans. <br />Some of the waste rock from the tunnel excavation was placed <br />back inside the tunnels, between the two concrete walls, one 25 <br />feet inside the tunnel, the other one at the surface opening. <br />Remaining waste material at benches and in front of the portals <br />has been sloped and covered with a minimum 16 inches of topsoil. <br />• All remaining water monitoring wells have been plugged according <br />to state regulations. At a minimum the casing was pulled, if <br />possible, and the hole filled within a few feet of the surface <br />with a bentonite grout. The upper portion of the holes were <br />backfilled with soil. In the case of the horizontal hole SK-3H, <br />the packer was pulled and the hole filled with bentonite grout. <br />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 <br />nature of the pre-development topography. The slopes around the <br />portals are nearly the same as those of the pre-mining <br />condition. The areas further downslope from the portal were <br />terraced. As discussed earlier, the flat terrace configuration <br />will keep run-off to a minimum and benefit vegetation through <br />diminished erosion and better water retention. The terraces <br />also promote livestock and wildlife feeding. The roads and <br />terraces will also facilitate the access to the individual <br />areas. <br />The post-mining final graded slopes promote a higher and better <br />use of the land for the pasturing, grazing, and watering of <br />livestock, the cropping, cultivation, and harvesting of plants <br />and wildlife grazing. <br />• NCIG - Coal Ridge No. 1 4-61 07-18-96 <br />