2013-02-15_REVISION - C1981020 (2)

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disturbances with the exception of the coal waste disposal site, which was approved by TR- 14, in 2002. The TR -11 plan included appropriate topographic maps, cross - sections, and stability analyses, indicating that the existing road and mine bench would be reclaimed in accordance with applicable requirements. The plan approved in TR -11 was updated and revised by subsequent revisions, particularly, particularly TR -16 and TR -22. Approved plans specify that the upper segment of the access road will be reclaimed in accordance with Rule 4.03.2(7). The short lower segment of access road on the Munger Creek valley floor east of the coal waste disposal area, and the entire road segment from the coal waste disposal area to State Highway 139 (designated as a haul road) will be retained for the postmining land use. The portal bench area will be reclaimed to a stable, approximate original contour configuration, with highwalls and depressions eliminated. The major portion of the backfilling and grading operations were completed in the summer of 2007. Interim reclamation was conducted at the mine bench area in 2001/2002. Coal material from clean-up of the Loma Loadout was hauled to the mine bench area as an initial step in the interim reclamation. The coaly material was spread and compacted in lifts at the base of the portal bench cut slope, in compliance with 4.10.4(3)(a) and (b), and the placement and compaction was inspected and certified by a registered professional engineer, in compliance with 4.09.1(11)(a) and (b). The coal fill (approximately 200' by 75' by up to 15' deep) was subsequently covered with an approximate 2 foot cover soil thickness, and seeded with the approved stabilization seed mix. P.E. certification of the backfill stability is included in Permit Appendix H, along with a stability analysis and associated documentation. The stability analysis was run for the final backfill configuration, with the influence of the coal backfill at the base of the highwall factored into the analysis. The stability analysis indicated a factor of safety of 1.78 for the final reclamation backfill. Final reclamation of the mine site and upper road included the construction of designed, riprapped ephemeral channels across the reclaimed area. Several ephemeral channels cross the lower segment of the road that will be retained, including two major channels (Munger Creek and a significant canyon tributary immediately to the west of the coal waste disposal). All of the drainages are currently culverted beneath the road, but during final reclamation the culverts along the road segment to be retained will be removed, and replaced with dry fords. Restoration of the channel segments along the lower road, including construction of dry fords, is addressed in narrative Sections 3.3.1, 3.3.4 (Lower Road), Table 3.9 -5, and Figure 2.2 -7C. The bridge spanning East Salt Creek will be left in place for the postmining land use. Eight different ephemeral drainages were to be reestablished across the mine bench area and the upper road segment. They are labeled A through H and can be located in Figures 3.1 -5 through 3.1 -7. Narrative regarding these reclaimed channels is found in Section 3.3.4 (Upper Road). Rip -rap keys are to be installed at the top and bottom of each reclaimed channel, except for those areas where rock outcrop is present. The rip -rap keys will ensure that the entrance and exit of each reclaimed channel will not erode during high flow. Extensive backfilling and grading plans associated with disturbances that had been planned 29