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<br />the site. The Lewis Gulch fill material was used to backfill the Golden Quality No. 5 <br />tipple azea and the Twin Pines No. 2 Mine portals. <br />In accordance with 4.14.1(2)(g)(ii), all backfill azeas are reclaimed in a stable <br />configuration. The Golden Quality No. 5 tipple backfill area has a final slope gradient <br />of approximately 4H:1 V. The portal backfill slopes range from approximately 3 ~fiH: l V <br />to approximately 4H:1V. Based upon the limited slope lengths and relatively gentle <br />gradients, all backfill slopes appear sufficiently stable to maintain the required safety <br />factor of 1.3. The slopes are compatible with the approved post-mining land uses of <br />rangeland and wildlife habitat. <br />In accordance with 4.14.1(2)(iii), the remaining highwall has been stabilized to the <br />extent possible. A bench has been intentionally installed and maintained above the <br />portal level and below the highwall. This bench is in place to catch any falling <br />materials. Additionally, athree-strand barbed wire fence has been installed along the <br />outer edge of the bench. This fence has been posted with signs which read <br />"Danger/Falling Material." Steep, undisturbed slopes above the highwall, and the lack <br />of available backfill material prevent any further stabilization of the highwall. <br />In accordance with 4.14.1(2)(iv), all exposed coal seams and potentially combustible <br />materials have been covered. There aze no toxic- and acid-forming materials at the <br />site. <br />In accordance with 4.14.1(2)(v), all reasonably available spoil material located within <br />the permit boundary approved and enforced since 1983 has been used to reclaim the <br />site. Spoil material located downslope from the mine and beyond the permit boundary <br />was placed prior to 1975, and has not been affected since then. The outslopes are <br />reasonably stabilized against erosion by vegetation, and any attempt to move this <br />relatively steep downslope material would cause hillslope stability and erosion <br />problems. Therefore, this material was deemed to be unavailable. <br />In conclusion, the pre-law highwall located at the Twin Pines No. 2 Mine site has been reclaimed to <br />the extent required by the provisions of Rule 4.14.1, and is approved in accordance with the <br />approximate original contour variance provisions of Rule 4.27.4. <br />All drainage and sediment control features required by and approved as part of Technical Revision <br />No. 7 have been installed. The lower Lewis Gulch sediment pond remains in place and functional. <br />Approximately 1500 cubic yards of material have been stockpiled adjacent to the upper pond for future <br />use in reclaiming the pond. <br />The mine waste rock pile has also been reclaimed in accordance with the approved plan. Reclamation <br />plans for the pile aze found on page 88 of the permit, including grading, cover depth and drainage <br />control requirements. <br />Since this site was severely disturbed by historic mining operations conducted prior to initiation of <br />operations under Permit No. C-83-058, a very small amount of topsoil was available for use during <br />reclamation. However, all available topsoil was redistributed on the reclaimed mine area. The <br />available topsoil was stockpiled in two piles located along the county road which provides access to <br />the site. Both pile locations have been properly graded, seeded and mulched. Additionally, silt fences <br />5 <br />