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~ ~ GEOTECH <br />Civil, Structural & Geotechnical Engineers <br />222 South Park Ave. Montrose, CO 81401 <br />(970) 249-6828 FAX (970) 249-0945 <br />CONCEPTUAL EVALUATION OF <br />SYLVESTER GULCH <br />ROADWAY CONSTRUCTION <br />FEASIBILITY <br />Executive Summary <br />This report discusses Buckhom Geotech's findings in assessing the general feasibility of <br />constructing a 5,750-foot-long access road up Sylvester Gulch. The analysis was based on a site <br />visit and review of existing studies, reports, maps, and photographs. Sylvester Gulch is a <br />narrow, steep sided canyon with potentially unstable slopes. However, our analysis has <br />concluded that a narrow road that is designed to limit cut/fill depths and accommodate surface <br />and subsurface drainage can be constructed to provide a basic level of service. The cost of such <br />a road in a most favorable scenario is estimated at azound $45 per linear foot. In a worst case <br />scenario, where significant slope stabilizing measures and drainage control structures are needed, <br />the cost could be as high as $200 per linear foot. The cost of roadway construction will increase <br />as its width is increased. Or, conversely, the narrower the road, the less it will cost. <br />Further analysis of design requirements and costs cannot be made without a detailed survey of <br />the alignment and testing of the soil material. <br />Overview <br />The proposed Sylvester Gulch Road extends about 5,750 feet in length and connects two existing <br />access roads within the West Elk Mine. Sylvester Gulch is generally asteep-sided, narrow <br />canyon trending initially towards the south and then bending towards the southeast and east. <br />Elevations vary from about 6,935 feet above mean sea level at the north end of the project to <br />over 7,470 feet at its east end. <br />The geologic map of the area shows the left canyon wall (moving in the upstream direction) to <br />consist of the Cretaceous Mesa Verde formation. This bedrock material is described as <br />interbedded sandstone, mudstone and shale with thin, non-commercial beds of coal. Bedrock is <br />exposed in numerous places along the lefr canyon wall and elsewhere the soil cover is thin. (A <br />Sylvester Gulch Road Feasibility, Preliminary Report <br />Job No. 01-345 <br />Page I of 4 <br />