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• May and early June of 1996. Signs of previous activity include the site road, abandoned mine <br />buildings and residences at the base of the project, scattered artifacts in the wck loadout area, <br />and two previously completed cased boreholes, marked DH-42, located next to our Boring 18, <br />and DH-55, located next to our Boring 13. <br />SITE GEOLOGY <br />Figure 2 presents a generalized geologic map of the project site. Most of the surface <br />facilities for the mine will be situated on an ancient landslide within steep terrain formed by <br />horizontally interbedded sandstone and shale of the Mesaverde Formation and underlying <br />Mancos Shale. The valley sides trend to northwest-southeast, parallel to a prominent nearly <br />• vertical joint set noted in the bedrock formation. Many IandsGdes are known in the project area. <br />Most slopes exposing formational rock typically exhibit some obvious active instability, usually <br />rotational sliding, translational flow or toppling. <br />The bedrock at this site consists of the nearly flat-lying Cretaceous age Mancos Shale <br />(Km), a transitional deep to shallow water-deposited marine shale with sandstone interbeds that <br />forms the base of the steep-sided valley in which the North Fork of the Gumtison River flows. <br />Outcrops of the Mancos Shale were not observed on the project site, but are observable on the <br />south valley side. Colluvium (Qc) generally covers the Mancos Shale, consisting of gravity- <br />deposited slopewash from the rocks above. Outcropping about 350 feet above the valley floor <br />is the Rollins Sandstone, a massive to bedded cemented beach sandstone about 100 feet thick that <br />forms the basal unit of the Cretaceous age Mesaverde Formation (Kmv). Above the Rollins <br />I. ~ S <br />