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• since the actual test showed a much higher density) <br />b) as compacted cohesion of 0.14 tons per square foot or 280 Ibs/sq.ft. (This is the low end of <br />the range in Table 1) <br />c) friction angle of 30 degrees. (This is also the low end of the range in Table 1). <br />Foundation (classified as an GM soil) <br />a) maximum dry density 82 Ibs/cu.ft (this is slightly lower than the actual test desnity) <br />b) as compacted cohesion of 0.0 tons per square foot or 0 Ibs/sq.ft.-(See Table 1) <br />c) friction angle of 33 degrees. (This is also below the low end of the range in Table 1). <br />Due to the possibility of different soils being present for both the dam and the foundation <br />material, various cases will be run with different strength parameters to account for any soil type <br />which could be encountered. <br />Since the slopes of the pond are mild (2.5:1) and the height is no greater than 10.0 feet, it is <br />shown that any possible combination of strength parameters will attain the long-term safety <br />factor of 1.3, therefore, no triaxial shear testing of the material has been done. Also, it would be <br />very difficult to get a representative sample from all the pond areas in question, therefore <br />varying cases would need to run regardless of the results of any single test. <br />4. Other Parameters Used in the Slooe Stability Analysis <br />The program SB-SLOPE was used to analyze the slope stability, which uses the Bishops <br />• F method of slices for cylindrical failure. It is not possible that the dam and foundation for this <br />case would result in a plane failure therefore, this failure type will not be studied. Map 1 shows <br />the dam geometry used for the input as well as the phreatic surface which will be used for the <br />worst case assuming that the pond is near full and has not yet been dewatered. <br />Other parameters of the analysis include a minimum depth of slice for a failure circle in the <br />embankment of 3.0 feet. Also, the limiting depth of a circle is an elevation of 10.0 feet, which is <br />the bottom of the drawing, well into the foundation soil. It is unlikely that the lowest factor of <br />safety would have a circle going this deep in the foundation soil, but it has also been chosen to <br />be conservative. <br />• <br />R&VISED MARCH zoos Attachment 2.05.3(3)-15-4 <br />