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VI. BACKFILLING AND GRADING <br />Information relevant to backfilling and grading is presented in Sections 3.0 and 3.3-1, <br />of the application. Postmining contour maps and cross sections are included as Figures <br />3.1-1 and 3.1-2, premine topogaphy is depicted on Figure 3.1-3, and a stability <br />analysis section is depicted on Figure 3.1-4. <br />The lower portion of the affected area will be returned to approximate original contour <br />(AOC), but the mine bench area will not be returned to AOC. The operator submitted <br />information in the original permit application, and in association with the 1985 permit <br />renewal demonstrating that the mine bench area qualified as steep slope mining pursuant <br />to 2.06 and 4.27. The Division approved a limited variance to the AOC requirements <br />of 4.14 and 4.27.3, to allow for backfilled slopes of lesser steepness, which would meet <br />applicable stability criteria and support the approved post-mine land use. Average <br />slopes in the mine bench area prior to mining ranged from 80% to 85%, whereas the <br />backfilled valley side slopes will range from approximately 40% to 60%. The <br />post-mine topogaphic configuration will be similar to premine, and stable drainage <br />channels will be reconstructed in their approximate original locations. The highwall will <br />be completely backfilled, with the natural sandstone outcrop which forms a near vertical <br />face above the portals to remain undisturbed. The existing cut slope along the south <br />side of the mine bench area will be cut back a short distance to tie in with the backfill, <br />and ensure a stable configuration. Stability analyses performed by the operator indicate <br />that the reclaimed slopes will achieve the required 1.3 factor of safety. <br />Adequacy issues raised by the Division during the review associated with RN-04 <br />included a request for additional reclaimed area cross sections for the mine bench area, <br />denoting approximating original, existing, and proposed reclamation configuration. <br />Narrative description of the proposed reclaimed configuration was amended to <br />correspond to the topogaphic maps and cross sections. <br />The Division is proposing to approve a modification of the general gading requirements <br />of 4.14.2 for reclamation to approximate original contour because the requirements of <br />4.27.1 and 4.27.4 have been met. Please see Section B.VII of this document. <br />VII. OPERATIONS ON STEEP SLOPES <br />A. The Division proposes to approve a variance from meeting approximate original <br />contour for reclaimed areas. This variance is proposed following a demonstration <br />that the requirements of Rule 2.06.4 and 2.06.5 have been met (4.27.3). In <br />addition the Division believes that the applicant has demonstrated that the <br />requirements of Rule 4.27.4 will be met. <br />Information upon which the above fmding is based can be found on pages 3-2 <br />through 3-5 of the permit application. The landowner request from the Bureau of <br />25 <br />u 116 <br />