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initial waste disposal at the Munger Canyon disposal site occurred in late November 2004. <br />Several small temporary coal waste stockpiles are approved in the vicinity of the product <br />coal stockpile at McClane. There is also an approved sediment drying area stockpile near <br />the McClane sediment pond. Material from these stockpile locations will be periodically <br />hauled to the permanent disposal site in the Munger Canyon permit area. <br />The McClane Canyon application also notes that rock slope material will be disposed of <br />in areas of the mine that are no longer actively producing coal, as authorized by MSHA. <br />As noted on page 7 of the Division's February 19, 1999 mid-term review document, <br />disposal within the mine is limited to rock generated during the normal course of mining <br />operations, in accordance with standard industry practice, and in compliance with <br />applicable MSHA requirements. Return of coal mine waste from the surface to <br />underground workings is not approved. <br />Non-coal waste (e.g. trash and non-coal combustibles) are stored in a dumpster on site and <br />hauled off for permanent disposal by a commercial trash company. There is no <br />permanent disposal of non-coal waste material on-site. <br />VI. BACKFILLING AND GRADING <br />Information relevant to backfilling and grading is presented in Sections 3.0 and 3.3-1, of <br />the application. Postmining contour maps and cross sections are included as Figures 3.1-1 <br />and 3.1-2, premine topography is depicted on Figure 3.1-3, and a stability analysis section <br />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 of <br />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 slopes <br />in the mine bench area prior to mining ranged from 80% to 85%, whereas the backfilled <br />valley side slopes will range from approximately 40% to 60%. The post-mine <br />topographic configuration will be similar to premine, and stable drainage channels will be <br />reconstructed in their approximate original locations. The highwall will be completely <br />backfilled, with the natural sandstone outcrop which forms a near vertical face above the <br />portals to remain undisturbed. The existing cut slope along the south side of the mine <br />bench area will be cut back a short distance to tie in with the backfill, and ensure a stable <br />configuration. Stability analyses performed by the operator indicate that the reclaimed <br />slopes will achieve the required 1.3 factor of safety. <br />The Division has previously approved a variance from the general grading 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 />24