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<br />3-11 <br />The sandstone outcrop above the portals is a natural rock outcrop and was not a result of <br />excavation. The average slope in the disturbed area will approximate original contours. The <br />existing cut slope on the south side of the mine bench will be cut back. Material from the upper <br />portions of the cut will be compacted along the toe of the slope to form a buttress. <br />Fgure 3.1.4 shows the existing cut slope as well as the slope proposed for reclamation. <br />The location of this section (labeled cc). is shown in Fgure 3.1.1. <br />Stability analyses were run for both the existing and proposed configurations. Since no site <br />specific information was available for soil strength parameters, results from Munger Canyon <br />tests were used. These numbers are as follows: <br />Friction Angle = 15 Degrees <br />Cohesion = 1300 PSF <br />• Density = 130 Ib/tuft <br />The analysis for the existing cut slope shows a safety factor of 1.234. This correlates well <br />with the history of this slope as it has been stable with only very minor surface sloughing. An <br />analysis of the proposed configuration (reclamation) shows an increase in the safety factor to <br />1.311. ft should be emphasized that these safety factors are not absolute, but do show that the <br />existing slope, which has been stable, will be improved upon reclamation. <br />Section CC was selected for this analysis because it exhibits the most severe slope in <br />the area to be reclaimed. The smaller cuts in this same area will be reclaimed using the same <br />techniques described herein. Grand Valley has compiled additional information concerning <br />reclamation of the mine bench at the request of CMLR. The information is in response to <br />Stipulation Number 11 of the May 5, 1985 permit approval and is contained in Section 3.0, and <br /> <br />Mc Volume 1 6-29-96 <br />