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6eah <br />• The slopes are very steep (about 360) and covered with about 5-10 feet of <br />slopewash and talus. No high terraces were observed near the site. A 5-15 <br />foot high scarp on each side of the river is evident indicating that the <br />river is downcutting. The river bottom consists of at least two flat terraces <br />with vegetation greatly obscuring the contacts. <br />The colluvium consists of gray and brown angular sedimentary rocks and <br />soils. The alluvium consists of rounded igneous and metamorphic rock with <br />rounded sandstone a rare occurrence. The cut scarps consist of the more angular <br />colluvium with some rounded boulders which were probably left by a high flood <br />flow. <br />The road cut and fill is on the upslope colluvium and into sedimentary rock. <br />It appears that the upslope location was chosen to get above the water level <br />for the 100 year flood. The top of the fill is above the scarp. The slump <br />seems to have occurred by lubricating (wet spring season) the talus above the <br />cut on such a steep slope. Due to the steepness of the slopes any cut into <br />this material will probably result in slumping. Several are evident down the <br />canyon. <br />DRILLING RESULTS <br />A drill hole near the site was bored on August 25, 1980, to determine litho- <br />logy and hydrologic information. The location is shown on Figure I and the drill <br />hole log is attached. About 25-30 feet of road fill and talus was encountered <br />but no alluvium. Essentially no water was encountered. Pio hydraulic connec- <br />tion with the alluvial aquifer is evident. <br />• Two drill holes at the proposed air intake shaft location were bored on <br />December 10, 1980, to determine lithology and hydrologic information. The drill <br />- 2 - <br />