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~• The engineering properties of the existing colluvium and landslide materials were obtained from the geotechnical investigations by Chen and Associates and Geo- Hydro Consulting, Inc. Properties for the backfill materials were based on those properties of the exisitng materiels, modified to account for the degree of compaction and saturation. It has been assumed herein that the backfill material most Iikely to be used, will have originally been part of those existing, natural materials. The effective stress parameters which have been used in these investigations are as follows. The Simplified Bishop Method satisfies overall moment and vertical force equilibrium oP individual slices, but does not satisfy the moment equilibrium of individual slices or horizontal forces equilibrium. However, this method is widely used, and hes been shown to produce accurate results over a wide range of soil conditions. C. Assumed Material Properties: Existing Materials ci ~, Friction angle Cohesion IInsaturated unit weight Saturated unit weight Backfill compacted to 85% of maximum density Friction angle Cohesion IInsaturated unit weight Saturated unit weight Friction angle Cohesion IInsaturated unit weight Saturated unit weight 30.5 Degrees 300 PSF 111 PCF 119 PCF Backfill compacted to 95% of maximum density 30.5 Degrees 300 PSF 115 PCF 120 PCF 33.0 Degrees 300 PSF 124 PCF 125 PCF D. Reclamation Alternatives at a Cross Section at Access Road Station 60+83 Station 60+83 of the access road is a critical road cross section in that portion of the road within the landslide area. A large cut at the portal road turnout has also been considered end is discussed in the next section. Six possible variations or alternatives for reclaiming the cross section at Access. Road Station 60+83 were analyzed. These cases are summarized in TABLE 1, below. C~