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2-28 shear force. An automatic search is incorporated by the program . in determining the most critical circle or lowest factor of safety. Four sections were analyzed to determine factors of safety. These sections are defined in Figures 2.2-7. SS through 2.2-7.BS. Assumed soil boundaries are as shown with the soil strengths noted on the sections. These sections were selected as the most critical and their locations are shown on Figures 2.2-7.2S and 2.2-7.45. A soil shear strength of 0 = 34°, C = 0.0 was used for the foun- dation material. This was based on triaxial testing performed on the foundation material and represents a drained or slow loading condition. Samples used for testing were taken by Geo- Hydro, Inc. and lab work was performed by Geo-Hydro, Inc. A copy of test results is included in Appendix Bs. • Since no refuse is available for testing, shear strength pro- perties of Q = 30° and C = 150 PSF were assigned to the refuse material. Reported values for eastern coarse refuse have a lower boundary of 0 = 28° and a cohesion of 400 PSF. More typically, values range from 33° to 35° for ~ with a cohesion in the range of 150-300 PSF. When refuse is generated, analysis will provide accurate values of physical properties to be expected. Since these more accurate values will be obtained while the refuse area is small and has no stability problems, designs can be evaluated to assess the appro- priateness of parameters used in stability analysis. If signifi- cant changes to the design of the refuse area are warranted, CMI.RB will be notified. Optimum final design incorporates slopes at 2H:1V with intermediate benches. This effectively reduces overall slope to 2.SH:1V. Incorporation of benches will also allow runoff from outslopes to be diverted, thus reducing runoff veloc- • ities and minimizing erosion.