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Golder Associates Inc. <br />200 Union Boulevard. Sulte 500 <br />Lakewood. CO USA 80228 <br />Telephone (303) 980 -0540 <br />Fax (303) 985 -2080 <br />January 9, 1996 <br />Cripple Creek & Victor Gold Mining Company <br />2755 State Highway 67 <br />Victor, CO 80860 <br />Attention: Mr. Ron Roberts <br />RE: SHEAR STRENGTH TESTING RESULTS FOR CRESSON ORE <br />Dear Ron, <br />Our Ref: 943 - 2847.001 <br />The shear strength of the Cresson Ore was determined from tests performed on samples of <br />Pad No. 2 material for the initial characterization . Ore from the Cresson Pit is currently <br />available and the Cripple Creek & Victor Gold Mining Company (CC &V) requested that <br />Golder Associates Inc. (Golder) evaluate the shear strength of the material that has been <br />placed in the Phase I Heap Leach Pad. Golder would like to take this opportunity to <br />present these results to CC &V. <br />The interface shear strength testing was performed in general accordance with the <br />procedure developed for the American Society for Testing and Materials (ASTM) Standard <br />Test Method D5321, "Determining the Coefficient of Soil and Geosynthetic or , <br />Geosynthetic and Geosynthetic Friction by the Direct Shear Method". Tests were <br />conducted at normal stresses ranging from 50 psi to 150 psi in a direct shear device <br />containing an upper and lower shear box. The upper shear box measures 12 inches by 12 <br />inches in plan and 3 inches in depth. The lower shear box measures 12 inches by 14 <br />inches in plan and 3 inches in depth <br />Cresson Ore material was screened to remove material in excess of 1-1 /2 inches.- The <br />screened ore was subjected t6 normal loads of 20 psi, 50 psi, 100 psi and 150 psi, and the <br />shear strength required to fail the sample was measured. From this testing, a normal stress <br />versus shear stress plot could be created in which the cohesion and friction angle for the <br />Cresson ore could be determined. <br />Testing results from the Cresson ore is presented in Attachment A. Based on the Iinear <br />regression performed on the four points, a friction angle of 38 degrees and a cohesion of <br />1275 psf were measured. Upon review of the data by Golder, a straight line was drawn <br />through the origin and the Cresson Ore material was assigned a friction angle of 40 <br />degrees and a cohesion value of 0 psf. <br />