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the base of the portal bench cut slope, in compliance with 4.10.4(3)(a) and (b), and the <br />placement and compaction was inspected and certified by a registered professional <br />engineer, in compliance with 4.09. 1 (1 1)(a) and (b). The coal fill (approximately 200' by <br />75' by up to 15' deep) was subsequently covered with an approximate 2 foot cover soil <br />thickness, and seeded with the approved stabilization seed mix. P.E. certification of <br />the backfill stability is included in Permit Appendix H, along with a stability analysis <br />and associated documentation. The stability analysis was run for the final backfill <br />configuration, with the influence of the coal backfill at the base of the highwall factored <br />into the analysis. The stability analysis indicated a factor of safety of 1.78 for the final <br />reclamation backfill. <br />Final reclamation of the mine site and upper road included the construction of <br />designed, riprapped ephemeral channels across the reclaimed area. Several ephemeral <br />channels cross the lower segment of the road that will be retained, including two major <br />channels (Munger Creek and a significant canyon tributary immediately to the west of <br />the coal waste disposal). All culverts along the road segment to be retained were removed <br />in 2015 and replaced with dry fords. Restoration of the channel segments along the <br />lower road, including construction of dry fords, is addressed in narrative Sections 3.3.1, <br />3.3.4 (Lower Road), Table 3.9-5, and Figure 2.2-7C. The bridge spanning East Salt <br />Creek will be left in place for the postmining land use. All culverts were removed in <br />2016. <br />Eight different ephemeral drainages were to be reestablished across the mine bench area <br />and the upper road segment. They are labeled A through H and can be located in Figures <br />3.1-5 through 3.1-7 of the permit. Narrative regarding these reclaimed channels is found <br />in Section 3.3.4 (Upper Road). Rip -rap keys are to be installed at the top and bottom <br />of each reclaimed channel, except for those areas where rock outcrop is present. The <br />rip -rap keys will ensure that the entrance and exit of each reclaimed channel will not <br />erode during high flow. <br />Extensive backfilling and grading plans associated with disturbances that had been <br />planned and approved at one time but were never constructed, were eliminated from <br />the permit in association with TR -16 mine plan changes, approved in January 2004. <br />During and following completion of reclamation grading work in the summer of 2007, <br />the Division became aware of instances where final reclamation slopes, permanent <br />channel specifications, and certain other elements of the final topography, differed from <br />approved designs, to varying extents. The operator was requested to submit a technical <br />revision application to address the circumstances that resulted in departures from the <br />approved design, and to provide certified "as -built" topographic maps and <br />specifications, demonstrating compliance with applicable regulatory criteria. The <br />requested documentation was submitted in Technical Revision No. 22 (TR -22), and <br />approved May 23, 2007. <br />The proposed operation is in compliance with the requirements of this section. <br />27 <br />