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ExtenOetl Page <br />III IIIIIIIiiIIII III <br />999 <br />bolder ASSOGICtlS Ino. <br />200 lJnion Boulevard, Suite 500 <br />lnkewood, CO USA 80228 <br />TataFhonef3C3)980-OSdO <br />Fax(303J985-2080 <br />August 18, 1995 <br />Cripple Creek & Victor Gold Mining Company <br />2755 State Highway 67 <br />Victor. CO 80860 <br />~~tes <br />Our Ref.: 953-2900.007 <br />RE: RELOCATED TAILINGS STABILITY RE-EVALUATION <br />Deaz John: <br />The original guidelices for the placement of the tailings material to be relocated from the <br />Carlton area to Upper Arequa Gulch were developed in the Response to Comments by <br />Technical Reviewer D. P. Engineering Inc. (DPE), January I8, 1994. In this document, <br />Golder Associates Inc. (Golder) and the Cripple Creek & Victor Gold Mining Company <br />(CC&V) stated that ~`te tailings would be placed in 18 inch lifts and compacted with 1 pass <br />of a dozer. The response stated that the placement method and compaction effort would be <br />used for the following reasons: <br />- Volume: Less storage volume is required in Upper Arequa Gulch to store the <br />tailings if the material is placed at a higher density; and, <br />- Stability: The relocated tailings will be covered with waste rock. Stability of <br />the relocated tailings and overlying waste rock is of concern only until the waste <br />rock is buttressed against the Highway 67 fill. Stability analysis for the <br />relocated tailings have been performed assuming the following effective strength <br />pazameters: a wet density of 120 pcf; a dry density of 110 pcf; and a friction <br />angle of 33 degrees. Maintairrirtg fully drained conditions (resulting in effective <br />strength parameters) in the tailings is therefore important. <br />Golder performed shear .strength testing for the Carlton Tailings material (March 14, 1994 <br />letter to Mr. Grant Shelton entitled "Test Fill Construction For the Cresson Project, <br />Structural Fill Material Utilizing Rockfill and Tailings jot Phase I Toe Berm"). Samples <br />were tested at confining pressures of 10 psi, 3U psi and 60 psi and indicated a friction <br />angle of 38 degrees, for drained conditions. The density and moisntre content vazied from <br />96.1 pcf @ 19.5% to 97.7 pcf @ 19.3%. <br />Golder has re-evaluated the results of the stability analysis performed on the tailings <br />relocated to Upper Arequa Gulch. The object of the analysis was to determine the <br />