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3. Slope Compatibility with Post - Mining Land Use <br />The proposed backfilled slope of 2.OH:1.OV, as shown in the portal <br />area cross - sections, was selected because it is the best balance <br />for a number of concerns. It is steep enough to reclaim as much of <br />the highwall as possible using all reasonably available material, <br />yet it is permanently stable, will revegetate and is compatible <br />with the post- mining land use. Steeper slopes are extremely <br />difficult for dozers to achieve; good compaction is difficult; <br />revegetat i on is difficult and erosion is more severe. Milder slopes <br />are possible but they reclaim lesser amounts of the highwall. <br />Very little topsoil exists naturally on steep slopes of these <br />elevations and none was salvaged during the initial portal bench <br />excavation. Therefore, Mid - Continent is committed to bring in <br />enough topsoil from a nearby borrow area to cover the backfilled <br />slope and the exposed bench area with 3" to 6" of soil. <br />The post- mining land use of wildlife habitat, recreation and <br />grazing will be served by the reclaimed configuration. Wildlife, <br />cattle and sheep can negotiate the 2.OH:1.OV slope with no problems <br />and will certainly welcome the portion of the flat bench that will <br />be revegetated. Also, avalanche chutes have been historically <br />identified at all portal areas. The leaving of a portion of the <br />flat bench area will serve to break avalanches from above and <br />protect wooded areas below. <br />Limited road access to the reclaimed bench areas could provide <br />excellent opportunities for picnicking, scenic viewing, wildlife <br />watching and hunting. It is felt that all human activity below the <br />highwall remnants should be discouraged. <br />4. Handling of Drainage <br />During mine operation, the runoff from each portal area was <br />delivered to sediment ponds and then discharged into the natural <br />drainage. Some of these ponds are located in areas that should be <br />backfilled. Others will remain. One aspect common to all portal <br />areas is the need to keep all runoff from the spoil outslope. This <br />would increase erosion and could possibly cause a failure of the <br />fill slope. <br />The post- mining drainage plans for each of the portal areas are <br />described below: <br />