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1 <br />area will be reclaimed by placing fill over the proposed portal <br />site and sloping it towards the south. <br />1.4 SUMMARY <br />The geologic reconnaissance trip along with information supplied <br />' by Western Associated Coal Company indicated that the local <br />bedrock is sloping five degrees east of north at a dip of <br />' approximately five to 12 degrees. At all proposed bedrock <br />excavations, bedrock is not dipping out of the slope but rather <br />it is either parallel or dipping into the slopes. The geologic <br />investigation indicated that the joint patterns in the bedrock <br />are primarily perpendicular to the bedding planes. This <br />' information, along with shear strength data from previous work in <br />the area, was used in a rock slope stability analysis. This <br />analysis indicated that the proposed portal cut for all <br />alternatives will be stable if excavated no steeper than 0.5 <br />vertical to 1.0 horizontal. The extent of the coal burn visually <br />' observed at the site and its effect on the overall stability of <br />the rock cut can only be determined during the actual excavation <br />process. Therefore, it is recommended that the portal excavation <br />' be closely monitored. The burn areas may require removal or <br />pinning if adverse conditions are found contrary to the stability <br />' analysis. <br />The circular slope stablity analysis performed on the various <br />bench configurations resulted in safety factors of over 1.5. <br />1 This analysis was performed utilizing slope stability charts to <br />determine factors of safety based on assumed shear strength <br />' 2 <br />