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ICI <br />• spoil is attributed to the 10-foot thick clay slope-wash layer present in the test pit at <br />this location. <br />Saoil Properties. The representative samples of typical spoil from each portal <br />location were then tested for compaction properties (standard Proctor) and direct <br />shear testing. For both of the bulk samples the materials larger than 3/8-inch were <br />scalped from the sample prior to testing. The coarser particles were not replaced in <br />the samples tested. This method is considered conservative, using the finer matrix <br />portion of the spoil without the influence due to gravel-sized or larger particles. <br />Direct shear tests were performed on remolded samples at 85 and 95 percent of <br />standard Proctor maximum dry density at approximately optimum moisture content. <br />The results of this testing is shown on Figs. A-3 through A-8. <br />Direct Shear Test Results. The results of the direct shear testing are <br />• summarized and shown graphically on Fig. A-9. Overall, the typical spoil from R1 <br />showed slightly lower strengths than the typical spoil from P3 which is to be <br />expected considering the higher clay content of the R1 typical spoil. The friction <br />angles for the two types of typical spoil were generally consistent at different degrees <br />of compaction, the cohesion varied depending on the degree of compaction. The <br />lowest strength value measured was a friction angle of 28 degrees with a cohesion <br />of 400. This is a residual strength for R1 typical spoil compacted at 85 percent of <br />maximum Proctor dry density. <br />STABILITY ANALYSIS <br />The stability of seven sections through the proposed portal areas were <br />analyzed. The location of the sections analyzed are shown on Figs. 2 and 4. The <br />results of the stability analysis are presented in Appendix B. The stability analysis <br />was performed using the program Slope/WTM developed by Slope International Ltd. <br />We used modified Bishop analysis methods for circular shaped failure surfaces. <br />• <br />LORENCITO COAL COMPANY, LLC <br />CTUT 25,863 t1 <br />