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has served to alter the shale to make it extremely resistant to <br />weathering. When cut to create the roads, the material is very <br />gravelly, hard, angular, and does not chemically weather to produce <br />residual clays and loam needed for revegetation. This type of <br />material generally has very little cohesion but has a high internal <br />angle of friction. <br />In certain road areas, past igneous activity has not occurred and <br />the resulting cut Mancos Shale material is more amenable to <br />weathering. It therefore has a higher percentage of fine material <br />and clay. It is easier for vegetation to re- establish in this <br />material and it usually has some cohesion and a lesser internal <br />angle of friction than the altered material. <br />Other road areas constructed near drainages show signs of poorly <br />sorted colluvial materials with cobbles and gravels mixed with <br />finer sands, silts and some clay. <br />Exhibit 1 shows the approximate locations of these different types <br />of materials with respect to the roads. <br />3 <br />