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anticipated cu[ and fill slopes along Roads "A" and "B", we have conducted stability analyses using the • <br />proposed cut and fill sections provided by the client and strength values obtained from the triaxial <br />shear and unconfined compression tests. This information was used with the microcomputer program <br />"SB-Slope" which uses the Simplified Bishop method of slices to calculate factors of safety. <br />During the stability analyses we conducted a total of eleven separate analyses. The results of the <br />stability analyses indicate that the factor of safety against failure for the fill slopes to be constructed <br />along Roads "A" and "B' ranged from 2.27 Cora 2.1(horizontal):1(vertical) slope at Station 89+00 along <br />Road "A" t > 1.92 forte 2.0:1 slope at Station 77+j0 along Road "B". These results indicate [hat the <br />~phs j proposed fdl slopes should be stable a[ the co~gurahons an }za7-e3"-- <br />D <br />The analyses also indicated that the cu[ slopes along Roads "A" and "B" should be stable at the <br />proposed configurations. The 2.0:1 cut slope at Station 126+00 along Road "A" exhibited a factor of <br />sa[ety of 2.21 and a factor of safety of 1.67 was obtained for the l.j:l cut slope to be constructed at <br />Station j7+j0 along Road "B". <br />It should be noted that the analyses completed above were conducted using the "effective" shear <br />strength coefficients obtained from the [riaxial shear tests. A number of the cut and fill slope analyses <br />were also completed using [he "total" shear svength coefficents and these results are also shown is <br />Appendix A. Based on the results, it appears that the factors of safety for the fill slopes will be reduced • <br />on the order of 030 to O.j6 and [hat the cut slopes constructed in the clays will be reduced by <br />approtdmately 0.64 if the "total" shear strength coefficients are used. <br />The risk of slope instability will be significantly iaaeased if seepage is encountered in the cuts. We do. <br />not anticipate seepage will be encountered. However, if seepage is encountered during cooswction, <br />we should be advised [o determine if additional measures will be required to stabilize the slope. <br />Good surface drainage should be provided around all permanent cuts and fills to direct surface runoff <br />away from the cut faces and fill slopes. All cut and fill slopes and other stripped areas should be <br />protected against erosion by revege[ation or other methods. Fills should also be benched into hillsides <br />exceeding 4 horizontal [0 1 vertical. A minimum bench width of 8 feet is recommended. <br />Comp-action: All fill materials placed in the embankments should be compacted to at least 9j% of the <br />maximum standard Proctor density and within 3% of the optimum moisture content, as determined in <br />accordance with ASTM D-698. The fill should be placed under controlled conditions and tested by a <br />soils engineer. The ground surface underlying all fills should be carefully prepazed by removing all <br />organic matter, scariFcation to a depth of 8 inches and recompacting to 9j% of the maximum standazd <br />Proctor density prior [o fill placement. The fill lifts should not exceed 8 inches in thickness, unless it <br />can be proven in the Geld that adequate compaction can be achieved with thicker lifts. The fill <br />materials should be free of topsoil, vegetation, brush and other deleterious substances and should not <br />contain rocks or lumps greater that 8 inches in size. <br />Borrow Materials: The clays, sandstone and clays[one bedrock materials encountered in the test holes • <br />drilled along the proposed haul road alignment will be suitable for use in the roadway embankment <br />6 <br />