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3. Strenath Parameters Used in Slone Stability Analysis <br />Based on Table 1 and the density tests, the soil materials for this analysis will have the following <br />strength parameters: <br />Embankment (classified as an SM -SC soil) <br />a) maximum dry density 119 Ibs /cu.ft (this is conservative since the actual test showed a much <br />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 the <br />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 material, <br />various cases will be run with different strength parameters to account for any soil type which could <br />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 shown <br />that any possible combination of strength parameters will attain the long -term safety factor of 1.3, <br />therefore, no triaxial shear testing of the material has been done. Also, it would be very difficult to <br />get a representative sample from all the pond areas in question, therefore varying cases would <br />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 method <br />of slices for cylindrical failure. It is not possible that the dam and foundation for this case would <br />result in a plane failure therefore, this failure type will not be studied. Map 1 shows the dam <br />geometry used for the input as well as the phreatic surface which will be used for the worst case <br />assuming that the pond is near full and has not yet been dewatered. <br />Attachment 2.05.3(3) -15 -7 <br />