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5.3.2 FLAG/Slope <br /> FLAC/Slope estimated lower factors of safety than SLOPE/W. Of the factors of safety <br /> estimated by FLAC/Slope and SLOPE/W, the limiting(i.e. lower) factor of safety was used <br /> in design. For the analysis case that considered a region of the highwall, the factors of safety <br /> were in line with those estimated in SLOPE/W providing confirmation. For the entire <br /> highwall with global properties,the factors of safety were consistently above 3.70 for all <br /> bench configurations presented in Table 8. For the regional model with weaker global <br /> properties, the factors of safety were around 1.28 to 1.30 for the presented bench <br /> configurations, except for Analysis Case 12 which considered the highwall without an <br /> intermediate bench. <br /> For Cases 9 and 13, which considered the section of the highwall below El. 7000 with the <br /> same properties used as the global models, the slope was shown to have a factor of safety of <br /> approximately 8.00. For Cases 10 and 14, where three benches below El. 7000 were <br /> considered with the regional properties, the factors of safety calculated by FLAC/Slope were <br /> around 1.90. <br /> When the highwall was modeled with a stability bench at El. 6650, the factors of safety <br /> calculated for the entire highwall modeled with global properties was about 3.80. When <br /> modeled with a stability bench width of 100 feet (Case 16), the region of the highwall <br /> modeled was found to be adequate and met stability criteria. A bench width of 50 feet(Case <br /> 18)resulted in a factor of safety just below the 1.20 criterion. <br /> As described above, the factors of safety calculated by FLAC/Slope and SLOPE/W were <br /> used in the strength reduction method to assess the margin of stability of the highwall. Using <br /> the factors of safety previously calculated by SLOPE/W, the resulting reduced material <br /> properties were used in Analysis Cases Analysis Cases 1-1, 3-1, 5-1, 7-1, and 11-1. The <br /> factors of safety calculated by FLAC/Slope for these models were consistently around 1.20, <br /> which meets minimum slope stability criteria. <br /> Reduced strengths estimated from factors of safety calculated by FLAC/Slope for the initial <br /> global models were used in Analysis Cases 1-2, 3-2, 5-2, 7-2, and 11-2. The factors of safety <br /> calculated by FLAC/Slope were all 1.40. As the strength reduction method used to estimate <br /> the reduced strengths is the same method used in FLAC/Slope, this is the expected safety <br /> factor for all analyses cases using the initial global safety factors calculated by FLAC/Slope <br /> Aggregate Industries Morrison Quarry GEI Consultants, Inc. <br /> AM-06 Geotechnical Stability Exhibit 35 August 2018 <br />