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• 2.06.5 Permits Incorporating Variances from Approximate Original Contour Restoration Requirements for Steep Slope Mining The operator has requested a variance from the approximate original contour requirements of Rule 4.27.3(3) as provided by Rule 4.27.4. The variance allows for a partial backfilling scheme which will ensure stability of the reclaimed surface at both the Bear No. 2 Mine and Bear No. 3 Mine portals. The portal at the Bear No. 2 Mine has been backfilled to an elevation approximately one-half the height of the highwall. According to a Rocky Mountain Geotechnical (RMG) Report dated August 25, 1981, (page 10), the backfill would achieve the required factor of safety of 1.3 if the high wall materials are assumed to have a minimum friction angle on the order of 41 degrees which RMG considered reasonable for the materials observed. The partial backfilling scheme for the Bear No. 3 Mine portals has not been implemented. According to a Rocky Mountain Geotechnical (RMG) Report dated April 16, 1982, (page 2), a minor reduction in stability conditions (on the order of 5$) will be experienced in a • post reclamation condition below the bench level due to the surcharge effect at the bench level from the portal backfilling operation. 2.06.6 Prime Farmlands This Section is not applicable to the mining operations planned by the operator. Since the negative determination of prime farmland was arrived at using the eligibility requirements established for prime farmland under Section 2.04.12, Prime Farmland Investigation, these performance standards do not apply to the permit application. 2.0.7 Variances for Delav in Contemporaneous Reclamation Requirements in Combined Surface and Underground Mining Operations The operator does not plan for combined surface and underground mining operations; therefore, the requirements for this section are not applicable. • 2.06-3 Rev. 01-31-96