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1 SCOPE This report presents results of our density testing and stability analysis of the Refuse Disposal Area at the New Elk Coal Mine in Weston, Colorado. The scope of our investigation was to estimate 1 the relative density of the existing refuse pile and to perform stability analyses to form an opinion of the mass stability of the existing and planned refuse configuration. This report describes field and laboratory procedures we used to pertorm additional field ~ density tests and our stability analyses. The density data were used to revise previous density tests based upon corrections for down-hole nuclear gauge moisture and density. We obtained comparatively undisturbed samples of the in-place materials and pertormed laboratory tests to estimate the shear strength of these materials. Analyses were pertormed to evaluate the stability of the existing refuse and to develop our opinions of the need for remedial actions to improve stability and measures a to maintain stability for the future refuse construction. SITE CONDITIONS ~ The Refuse Disposal Area (RDA) is located in a gulch sloping upward north of Colorado Highway 12 on the New Elk Mine property (Fig. 1). A belt conveyor places refuse at the south edge of the disposal area and a tracked loader is then used to distribute the refuse around the area. We ~ understand the loader is the sole source of compactive effort. At the time of this investigation, the filled area was approximately 500 feet wide, 165 feet deep at the south end and tapered to the north approximately 1100 feet from the south edge. The fill surface will enlarge as the fill rises in the future. • The design calls fora 2:1 (horizontal to vertical) slope on the face, withtwenty-toot wide benches every r fifty feet of vertical rise. The RDA will extend approximately 7,800 feet from the south toe to the northern boundary and will reach a maximum depth of approximately 300 feet (Fig. 2). •