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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 /> Fanthert arth Asaatudes <br /> CONSULTING GEOTECHNICAL ENGINEERS AND <br /> MATERIAL TESTING <br /> Appendix 2.05.3(4)-6 Page 9 December 2018(TR-19) <br />