Laserfiche WebLink
7 of the Division's February 19, 1999 mid-teen review document, disposal within the mine is <br />limited to rock generated during the normal cowse of mining operations, in accordance with <br />standard industry practice, and in compliance with applicable MSHA requvements. Return of <br />coal mine waste from the surface to underground workings is not approved. <br />Non-coal waste (e.g. trash and non-coal combustibles) are stored in a dumpster on site and hauled <br />off for permanent disposal by a commercial trash company. There is no permanent disposal of <br />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 the <br />application. Postmining contow maps and cross sections are included as Figwes 3.1-1 and 3.1-2, <br />premine topography is depicted on Figure 3.1-3, and a stability analysis section is depicted on <br />Figure 3.1-4. <br />The lower portion of the affected azea will be returned to approximate original contow (AOC), but <br />the mine bench area will not be returned to AOC. The operator submitted information in the <br />original permit application, and in association with the 1985 permit renewal demonstrating that the <br />mine bench azea qualified as steep slope mining pursuant to 2.06 and 4.27. The Division approved <br />a limited variance to the AOC requirements of 4.14 and 4.27.3, to allow for backfilled slopes of <br />lesser steepness, which would meet applicable stability criteria and support the approved post- <br />mine land use. Average slopes in the mine bench azea prior to mining ranged from 80% to 85%, <br />whereas the backfilled valley side slopes will range from approximately 40% to 60%. The <br />post-mine topographic configuration will be similar to premine, and stable drainage channels will <br />be reconstructed in their approximate original locations. The highwall will be completely <br />backfilled, with the natwal sandstone outcrop which forms a near vertical face above the portals to <br />remain undistwbed. The existing cut slope along the south side of the mine bench area will be cut <br />back a short distance to tie in with the backfill, and enswe a stable configuration. Stability <br />analyses performed by the operator indicate that the reclaimed slopes will achieve the required 1.3 <br />factor of safety. <br />The Division has previously approved a vaziance from the general grading requirements of 4.14.2 <br />for reclamation to approximate original contow because the requirements of 4.27.1 and 4.27.4 <br />have been met. Please see Section B.VII ofthis document. <br />VII. OPERATIONS ON STEEP SLOPES <br />The Division proposes to approve a variance from meeting approximate original contour for <br />reclaimed areas. This variance is proposed following a demonstration that the requirements of <br />Rule 2.06.4 and 2.06.5 have been met (4.27.3). In addition the Division fmds the applicant has <br />demonstrated that the 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 through 3-5 of the <br />permit application. The landowner request from the Bureau of Land Management (BLM), <br />pursuant to Rules 4.27.4(4) and 2.06.5(2)(e), is included in Appendix K, of Volume N, of the <br />permit application. <br />21 <br />