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326 <br />• The stabilrty analysis was performed using a program developed at the University of <br />Kentucky called REAME. The program allows the user to create a data set to define the soil <br />horizons and rock layers. The soil parameters, conditions of failure and trial centers are <br />defined. REAME then calculates the lowest factor of safety for the data set, working from the <br />trial center to the location of the lowest factor of safety . The reports generated by REAME <br />were edited to fit on one page each and are contained in Table 3.9.4. <br />STATION 18+00 <br />The analysis of this area was complicated by the fact that the original slope was not <br />extremely stable, a common condition in the mine area. The analysis of the assumed original <br />slope indicates a factor of safety of only 1.154. The existing configuration with the road has a <br />factor of safety of 1.081. Since the slope has shown no tendency of failing in the nearly twenty <br />years that the roads has been in place, it is assumed that the soil parameters or underground <br />stratigraphy is not accurately defined within the data set. Although a "true" factor of safety will <br />not be generated ,the relative stability of the various configurations can be attained. <br />• The next configuration that was tested for this line was for the reclaimed configuration. The <br />analysis yielded a factor of safety of 1.166. The reclaimed configuration includes backfilling the <br />cut with material that will be compacted to achieve a density of 135 pounds per cubic foot, while <br />it was assumed that the original ground has a density of 120 pounds per cubic foot. The backfill <br />was also assumed to have a higher cohesion, 300 vs. 200 psf, since it will be a blend of the <br />existing gravelly material and the highly cohesive soils found in the upper portions of the road. ft <br />was noted that none of the failure circles generated by REAME intersected the reclamation <br />backfill. Therefore, the failure would occur in the host material not in the backfill. <br />Since this analysis did not yield a factor of safety of 1.3 or higher, and none of failure <br />circles involved the backfill, analysis of just the backfill was performed. The analysis of the <br />backfill itself indicates a factor of safety of 2.115. Since the backfill is shown to be stable, the <br />stability of the original configuration is the weak point. No effort to enhance the overall stability <br />of the slope would be capable of creating a 1.3 factor of safety without a major reduction in the <br />steepness of the original slope. This option is not feasible. <br />• <br />M~ Volume i 12 - l8 - 96 <br />