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West Elk Mrne Description o(Possible Subsidence Consequences - 2.05.6(6)(61(1) Pre- and Post-mining Land Uses -2.05.6 (6)(b)(i)(A) According to the Environmental Analysis U-94-37 prepazed by the U.S. Bureau of Land Management (BLM) in cooperation with the U.S. Forest Service (USFS) and the U.S. Office of Surface Mining (OSM) dated November 1994, the permit azea lands support wildlife use, dispersed recreation, and livestock grazing. The Forest Service Amended Land Resource Management Plan prescribed designation of the Box Canyon lease tract and surrounding USFS lands is "6B," which emphasizes livestock grazing and may provide recreational opportunities for semi-primitive non-motorized, semi-primitive motorized and roaded natural settings. The azea is generally open to off-road motorized use, as identified on the "Gunnison Area Basin" National Forest map. It is anticipated that little or no impacts to the wildlife and domestic livestock and their respective habitat will occur as a consequence ofmining-induced subsidence on the permit azea. In the unlikely event that subsidence effects disturb the wildlife and domestic livestock, reclamation of the site will be to those land uses which existed prior to mining. Effects of Mining on Surficial Geologic Features When evaluating the effects of mining in the perrnit area, the present land use, the post-mining land use and the effects of previous mining in the azea should be considered. Present land uses primarily include wildlife habitat, recreational hunting, and livestock grazing. Post-mining land use will be the same: wildlife habitat, recreational hunting, and livestock grazing. Evaluation of the effects of past and current longwall mining on surface features indicates that surface cracks and visible surface effects aze rare and have been documented in only five locations: 1. Numerous cracks occurred in the meadow above and south of the West Elk Mine surface Facilities. Some question exists as to whether these represented subsidence cracks or resulted from slight movement of the lazge landslide complex. Even if they were subsidence cracks, the cracks resulted from room-and-pillar mining, not longwall mining, as the cracks occurred above the F-Seam room-and-pillar areas shortly after they were mined, and north of the area of influence of longwall mining. 2. Cracks occurred on the point of a high ridge immediately north of the forks of Lone Pine Gulch neaz the center of the south line of Section 17. Cursory surface investigation found no evidence that the cracks extended into the shales below a prominent sandstone ledge. Assessing the subsidence cause and relationships of these unique cracks is difficult. These cracks occurred along the south boundary of room-and-pillar B and C-Seam mining by • Beaz Coal Company, along the north boundary of MCC F-Seam room-and-pillaz mining and 700 feet north and east of the boundaries of MCC's B-Seam longwall panels. The 2.05-102 Revised Jun. 1995 PR06; 1/96RN03; Revised May 1999 TR89; Revised Jan 1998 PR08;March 2005 PRl7 `h I~ o