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page Three <br />7 January 2013 <br />M12058MT <br />Our stability analyses of the embankment slope was based on the <br />Bishops Method of Slices. This method is based on the assumption <br />that the slope soil mass will fail in a rotation mode on a <br />circular arc plane. In this method of analysis the mass of soil <br />is divided into vertical slices. The forces acting on each slice <br />are evaluated from the equilibrium of the slices; that is, the <br />forces that tend to drive the slice downhill and the forces that <br />tend to resist the movement of the slice. The equilibrium of the <br />entire mass is determined by summing the driving and summing the <br />resisting forces acting on all slices and comparing these forces. <br />Our slope stability analysis was performed using "Slope <br />Stability Analysis" by Geosoft computer software. Our slope <br />stability analysis considered one (1) assumed a typical cross <br />section, as noted above, with a total of about 225 separate <br />possible failure surface iterations to help identify the <br />potential theoretical slope stability. Our discussions and data <br />presentation are based only on the calculated critical circle <br />which presented the lowest factor of safety against failure. Our <br />presentation does not include the results of all of the itera- <br />tions which resulted in a theoretical factor of safety greater <br />than the lowest factor of safety and therefore were not critical. <br />Our analysis was based on laboratory strength test results for <br />the fill material. The soil strength values used in our analysis <br />included: <br />an internal angle of friction (phi) of sixteen (16) <br />degrees, <br />. cohesion of one -hundred twenty-eight (128) pounds per <br />square foot and <br />. a moist unit weight of 122.6 pounds per cubic foot, which <br />is the average of the passing field density tests of the <br />embankment material. <br />The configuration was also calculated using a moist unit <br />weight of 115 pcf. <br />The height of the embankment slope used in the analysis was 9.5 <br />feet. The crest width of the embankment is 10 feet and the slope <br />inclination is three (3) to one (1) (horizontal to vertical). <br />The calculated theoretical factor of safety for the configuration <br />and the soil strength parameters discussed above is 1.76 (122.6 <br />pcf) and 1.73 (115 pcf), <br />C_rt <br />CONSULTING GEOTECHNICAL ENGINEERS AND <br />MATERIAL TESTING <br />Appendix 2.05.3(4)-6 Page 9 December 2018 (TR -19) <br />