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IX. Coal Mine Waste <br /> 1. The Division proposes to approve a plan for extinguishing coal mine waste fires. <br /> This plan has been approved by MSHA and contains provisions about who will <br /> be involved in the extinguishing operations (4.11.1). The plan can be found in <br /> Exhibit 65 in Volume 11 of the permit document. <br /> 2. No coal mine waste from the West Elk Mine is proposed to be returned to <br /> underground workings (4.11.3). <br /> 3. Disposal of non-coal waste will be handled as required (4.11.4). <br /> 4. No dams or embankments constructed of coal mine waste have been or are <br /> proposed to be constructed (4.11.5). <br /> X. Backfilling and Grading <br /> The Backfilling and Grading plan can be found throughout Section 2.05.4. <br /> Exhibit 54 of the permit document contains detailed information regarding <br /> abandonment and sealing of portals. Maps 58, 58A, 58B, and 59 show post-mining <br /> topography. <br /> During the course of MCC's study of the original West Elk lease property and the <br /> Jumbo Mountain lease area, numerous slope failures and rock falls were identified. <br /> Landslides and rockfalls identified during their study are delineated on Map 32 and <br /> 32A. However, MCC also observed that it believes such slope problems would have <br /> a minimal effect on the operation and these areas can be stabilized or removed when <br /> the facility is built. <br /> In order to judge the credibility of MCC's statements regarding slope stability, the <br /> Division requested the submittal of supporting information. MCC responded by <br /> submitting a report prepared by Geo-Hydro Consultants, Inc., entitled "Landslide <br /> Study, Geo-Hydro Consultants, Mt. Gunnison No. I Mine," included within the <br /> permit document in Exhibit 14. This report, prepared in conformance with.the <br /> current state-of-the-art, includes design recommendations for the surface facilities to <br /> be constructed within the landslide deposit delineated in the surface facility area of <br /> the West Elk Mine site. One of the design recommendations forwarded within the <br /> report is the installation of a dewatering system consisting of horizontally inclined <br /> dewatering wells installed throughout the affected area, specifically within the portal <br /> bench and access road. Specific engineering design plans for this system have been <br /> included within the permit document. In addition, intricate bin-wall retaining <br /> structures were subsequently included within the design documents in the permit <br /> section. <br /> The area of the surface facilities has been the focus of historic and recent landslide <br /> activity. The Division required MCC to demonstrate, through appropriate <br /> geotechnical analyses, that the proposed backfilled surfaces would satisfy the required <br /> static slope safety factor of 1.3. Merrick and Company prepared a 'Report of <br /> 47 <br />