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Exhibit 1 shows a cross-section of the existing embankment. The <br />analysis was performed using this geometric configuration. <br />The material labelled Soil 1 is the natural unconsolidated <br />material below the dam before bedrock is reached. This material <br />is approximately 2 feet thick, as determined when the incised <br />portion of the pond was dug. Consolidated material was found when <br />the bottom of the pond was excavated. This two feet thick layer <br />of unconsolidated material is a mixture of a class GC and a class <br />SC material, consisting of poorly graded clays, silts and sands <br />with some gravel material, According to the table from Huang, it <br />is assumed that this material will have a cohesion of 500 <br />lb/sq.ft. and a friction angle of 28 degrees. These numbers are <br />conservative and additional cases are shown with even lower <br />numbers. <br />Initially, the existing slope was modelled, using the strength <br />parameters shown above. This resulted in a safety factor of 6.359 <br />which is extremely stable. A minimum depth of tallest slice of <br />zero was used in the analysis so that all circles would be <br />computed. <br />Exhibit 1 shows the details of modelling this slope, including <br />the coordinates of the durable rock below the fill and the fill <br />itself. A]so shown is the failure line for three different cases. <br />Two other cases were performed, varying the strength parameters <br />each time. The results of all cases are as follows: <br /> Base Base Base Dam Dam Dam <br /> Unconsol. Cohes. Dens. Fill Cohe Dens. <br />Case # F. Angie lb/f t2 lb ft3 F. Angle lb ft~ Ib ft3 SF <br /> <br />1 28 500 106 17 900 115 6.35 <br />2 17 250 100 10 300 102 3.15 <br />3 13 200 100 8 100 100 1.55 <br />