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Prior to triaxial shear testing, the material was screened using a screen with 3/8 inch openings. Approximately 23~ of the material was larger than this opening. The triaxial test was performed on the material passing this screen. It is felt that this is representative of the distribution in the fill because no construction techniques were used that would create areas of high fines or large gravel areas. The triaxial tests were performed at three different confining pressures of 7, 14 and 21 psi. The results at all three confining pressures, when graphed, produce the internal friction angle and cohesion of the material. The direct shear tests were performed at the actual density of the placed material or 116 lbs/cu.ft - dry. The GSI tests showed a cohesion of 900 psf and an internal angle of friction of 14 degrees. This is reasonable for a fill comprised of clay with considerable silt and rock fragments. Since the friction angle was determined for the material passing the 3/8 screen and this material represented only 77~ of the total sample, an adjustment must be made for the total materiai. All material not passing through this sieve is greater than 3/8 inch in diameter. This material will have little cohesion, however, its internal friction angle should be even greater, up to 44 degrees. See the enclosed table from "Stability Analysis of Earth Slopes" by DR. Yang Huang describing the average effective shear strength of compacted soils. Therefore, the internal angle of friction of the overall material is more accurately stated as 17 degrees. A number of cases at different cohesions and friction angles will be evaluated. The REAME computer model for slope stability analysis developed by Yang Huang of the University of Kentucky is used in determining the slope safety factor of the rock fill. This program is based on the Bishop's method of slices for cylindrical failure. The material properties for the dam fill used as input for the program are as follows: Dry Density 115 lbs/cu.ft Cohesion 900 lbs/sq.ft. Angle of Friction 17 degrees