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0 <br />• order of 1.5 to 1.7. Although these may be considered adequate, suitable drainage <br />through this zone is still considered necessary. <br />A pseudo-static earthquake analysis is appropriate since liquefaction of <br />foundation soils is not considered likely. Pseudo-static horizontal coefficients of 0.05, <br />0.10 and 0.15 were evaluated. The calculated factor of safety and a 0.05 coefficient was <br />1.6. With the 0.15 coefficient a factor of safety of over 1.2 is calculated. We believe the <br />hazard classification associated with the fills (remote location, lack of population or <br />public improvement) indicates these results are satisfactory. <br />To summarize, static analysis shows adequate factors of safety (>1.5) for the <br />range of strengths evaluated. Buildup of water in the fills results in potential slumping <br />near the toe, indicating drainage is required: Pseudo-static analysis indicates <br />satisfactory conditions (F.S > 1.3). <br />A parametric analysis was performed for Fill 7-2 which has a steeper base slope <br />• that the model used for remaining excess spoil fills. Adequate factors of safety were <br />calculated (Fig. C-24). <br />Contour and Surface Mine Fills <br />For these configurations (Fig. C-2) the spoil properties control stability. The <br />lower bound friction angle of 30 degrees results in a factor of safety of 1.4 (Table C-1). <br />Psuedo-static earthquake analysis with a horizontal coefficient of 0.1 results in a factor <br />of safety of 1.3. Our analysis indicates a slope of 2.5:1 is appropriate for these fills. <br />Sedimentary Pond Embankments <br />The previous analysis performed for small sedimentation ponds (Job No. 26,559) <br />is considered appropriate (Refer to Appendix D). The soil properties used are <br />• LORENCITO COAL COMPANY, LLC <br />LORENCITO SURFACE MINE -PHASE I <br />CTLR 72, 611 <br />11 <br />