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;; . <br />• infer that the general conditions will improve to the east <br />(up valley) with the depth to residual soil/weathered rock <br />Uecoming shallower. <br />We observed the waste dump material being placed <br />r during the course of our field work and obtained representa- <br />R1 tive samples. Tl~e material was primarily a silty fine to <br />coarse sand and gravel with varying amounts of cobbles and <br />boulders. A grain-size analysis of a representative small <br />sample is presented in the Appendix. Based on the behavior <br />of the waste dump embankment and the effective angle of re- <br />pose (measured in the field to be about 380 to 42°), we con- <br />L servatively estimate that the material has a friction angle <br />of 34° to 380. It is our understanding that the waste dump <br />( material will become coarser and cleaner (contain less silt) <br />r as the open pit excavation proceeds into sounder unweathered <br />i rock and as the blasting%fx-agmentat ion portion of the waste <br />• removal effort is optimized. <br />3.5 Ground Water Conditions <br />1 Based on our explorations, the ground water table <br />occurred at a depth of about 30 to 40 feet west of boring <br />f BH-105. The ground water table appears to slope toward Good <br />Spring Creek at about 1-20. East of BIi-105, the water table <br />L was not encountered. <br />After heavy rain and/or during heavy snow melt, <br />areas of perched ground water probably occur. Due to the <br />structure of the bedrock, perched water mny seep out of the <br />canyon walls and discharge into Streeter Creek or percolate <br />~, down to the true ground water table. <br />I <br />