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TABLE 1 1 Reclamation Alternatives at a Cross Section at Access Road Station 60+83 with Corresponding Factors of Safety Refer Dewatering Degree Upslope Minimum Cese to Exhibit System left of Retaining wall Factor of ' Number Number In Place Compaction Left in place Safety 1 1 No 85% No 1.045 2 1 No 95% No 1.058 3 1 No 85% Yes 1.044 4 2 Yes• 85% No 1.691 S 2 Yes 95% No 1.6?5 ' 6 2 Yes 85% Yes 1.676 It is concluded from these analyses, as shown in this table, that, in order to meet the requirement for the minimum factor of safety of 1.3, the dewatering system must be fully operable. This is not unexpected since this area has been deemed as a potential slide area and the Factor of Safety in its natural in-place saturated state has been shown by Geo Hydro to be slightly above 1.0. This supports the recommendation by Geo-Hydro concerning the need for dewatering in this area. Other conclusions which can be made from these results concern the effect of extra compaction and the effect of burying in place the upslope retaining wall. Hoth cases had negligible effect on the minimum factor of safety. In fact, for the dewatering cases, both the higher degree of compaction and the buried upslope retaining wall produced a reduction in the minimum factor of safety. It should be pointed out, however, that for this type of analysis only two significant figures, or perhaps three significant figures in ' the most tightly controlled areas, are appropriate for comparing results. Therefore, to ensure a stability Faetor of Safety of at least 1.3 at Access Road Station 60+83, the full cross section of dewatering system must be in effect. To return this section to its approximate original condition end contours, the downslope retaining wall must be removed and the section should be backfilled in uniform lifts to approximately 85% of the maximum standard proctor density. The upslope retaining wall can be removed or left in place since its affect an stability is neglible. Ie it is left in place, the top segment should be removed so that the top soil depth will not be intercepted by any binwall material. An attempt should be made to protect all piezometers so that the ' dewatering system can be monitored after all reclamation procedures have been completed. Any areas not being effectively dewatered should be delineated and the horizontal drains should be re-drilled in theses areas. ' Therefore, at the cross section at Access Road Station as"0+83, the following procedure is recommended for reclamation to ensure a Stability Factor of Safety of 1.3 or greater. 1