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X. Backfilling and Grading <br />The Backfilling and Grading plan can be found throughout Section 2.05.4. Exhibit 54 <br />of the permit document contains detailed information regarding abandonment and <br />sealing of portals. Maps 58, 58A, 58B, and 59 show post-mining topography. <br />During the course of MCC's study of the original West Elk lease property and the Jumbo <br />Mountain lease area, numerous slope failures and rock falls were identified. Landslides <br />and rockfalls identified during their study are delineated on Map 32 and 32A. However, <br />MCC also observed that it believes such slope problems would have a minimal effect on <br />the operation and these areas can be stabilized or removed when 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 Study, <br />Geo-Hydro Consultants, Mt. Gunnison No. 1 Mine," included within the permit <br />document in Exhibit 14. This report, prepared in conformance with the current <br />state-of-the-art, includes design recommendations for the surface facilities to be <br />constructed within the landslide deposit delineated in the surface facility area of the <br />West Elk Mine site. One of the design recommendations forwarded within the report is <br />the installation of a dewatering system consisting of horizontally inclined dewatering <br />wells installed throughout the affected area, specifically within the portal bench and <br />access road. Specific engineering design plans for this system have been included <br />within the permit document. In addition, intricate bin-wall retaining structures were <br />subsequently included within the design documents in the permit 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 geotechnical <br />analyses, that the proposed backfilled surfaces would satisfy the required static slope <br />safety factor of 1.3. Merrick and Company prepared a "Report of Stability Analyses and <br />Recommendations for Reclaimed Surface Facilities at the West Elk Coal Company, Mt. <br />Gunnison No. 1 Mine." The report presents the results of the required stability analyses <br />and recommendations for reclamation of the affected area. <br />MCC proposes to return all surface disturbed areas to approximate original contour, <br />with the exception of the waste disposal sites. <br />XI. Revegetation <br />information regarding the vegetation in the West Elk Mine permit area is found in <br />Section 2.04.10, 2.05.4, Exhibit 31, 32, 33, Map 42, 43, and 44 of the permit document. <br />No threatened and/or endangered plant species were found anywhere within the permit <br />area. <br />Success of revegetation efforts was originally based on reference areas established in <br />July 1980 and enlarged in 1981. Reference areas were established for mixed shrub and <br />dry meadow communities and were shown on Map 44. <br />44