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stability analysis was run for the final backfill configuration, with the influence of the coal <br />backfill at the base of the highwall factored into the analysis. The stability analysis indicated <br />a factor of safety of 1.78 for the final reclamation backfill. <br />Final reclamation of the mine site and upper road included the construction of designed, <br />riprapped ephemeral channels across the reclaimed area. Several ephemeral channels cross <br />the lower segment of the road that will be retained, including two major channels (Munger <br />Creek and a significant canyon tributary immediately to the west of the coal waste disposal). <br />All of the drainages are currently culverted beneath the road, but during final reclamation the <br />culverts along the road segment to be retained will be removed, and replaced with dry fords. <br />Restoration of the channel segments along the lower road, including construction of dry <br />fords, is addressed in narrative Sections 3.3.1, 3.3.4 (Lower Road), Table 3.9-5, and Figure <br />2.2-7C. The bridge spanning East Salt Creek will be left in place for the postmining land <br />use. <br />Eight different ephemeral drainages were to be reestablished across the mine bench area and <br />the upper road segment. They are labeled A through H and can be located in Figures 3.1-5 <br />through 3.1-7. Narrative regarding these reclaimed channels is found in Section 3.3.4 (Upper <br />Road). Rip-rap keys are to be installed at the top and bottom of each reclaimed channel, <br />except for those areas where rock outcrop is present. The rip-rap keys will ensure that the <br />entrance and exit of each reclaimed channel will not erode during high flow. <br />Extensive backfilling and grading plans associated with disturbances that had been planned <br />and approved at one time but were never constructed, were eliminated from the permit in <br />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, the <br />Division became aware of instances where final reclamation slopes, permanent channel <br />specifications, and certain other elements of the final topography, differed from approved <br />designs, to varying extents. The operator was requested to submit a technical revision <br />application to address the circumstances that resulted in departures from the approved design, <br />and to provide certified "as-built" topographic maps and specifications, demonstrating <br />compliance with applicable regulatory criteria. The requested documentation was submitted <br />in Technical Revision No. 22 (TR-22), which is currently under review. <br />The proposed operation is in compliance with the requirements of this section. <br />IX. Revegetation <br />Baseline vegetation information for the Munger Canyon Mine can be found in Section 4.8 of <br />Volume I; the Vegetation Map is included as Figure 4.8-1 in Volume 2. The Division has <br />reviewed this portion of the application and determined that the information is adequate. All <br />previous concerns relating to the baseline vegetation information section of the initial <br />permanent program permit application have been resolved. <br />34