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The strong coloring of the Wasatch (Ruby) Formation <br />contrasts sharply with that of the light-colored Ohio Creek <br />Conglomerate and with the sandstone of the Mesaverde <br />Group. Conglomerate and sandstone predominate in the <br />lower 100 feet of the Wasatch (Ruby) Formation. Several <br />boulders of scoriaceuos basalt as much as 2-1/2 feet in <br />diameter are present, and smaller pebbles of chert, jasperoid <br />quartz, and a vaziety of igneous and metamorphic rocks are <br />widely distributed. Above the conglomerate and sandstone <br />zone, red and green shale and silt predominate. <br />The local geology azound the Blue Ribbon Mine consists of <br />Tertiary and Cretacious sediments that strike north 77 degrees <br />west and dip from 1 to 3 degrees to the northeast. These <br />sediments have been incised by erosion, creating a topography <br />characterized by deep canyons that control drainage patterns <br />which flow into the North Fork of the Gunnison River and <br />eventually into the Colorado River. Geologic studies both in <br />the field and of new lazge scale, color, aerial photographs do <br />not reveal any folding or faulting in the area. This has also <br />been upheld by the fact that no faulting has yet been <br />encountered in the workings of the Blue Ribbon Mine. <br />The overburden of the Blue Ribbon Mine ranges from a few <br />feet to approximately 1,450 feet. <br />b. Groundwater <br />The lazgest and most useful alluvial deposits found in the <br />region aze associated with the North Fork of the Gunnison <br />River. Smaller, more isolated alluvial deposits aze associated <br />with several of the other tributaries of the North Fork. <br />Directly adjacent to the Blue Ribbon Mine along Hubbazd <br />Creek is a small alluvial deposit. <br />The most continuous sandstone unit of any significance in the <br />region aze the Rollins Sandstone and the massive sandstone <br />separating the upper and lower coal members of the <br />Mesaverde formation. However, the latter massive sandstone <br />produces very little water, as evidenced by the dryness of the <br />Beaz Mine and the lack of springs associated with this unit. <br />Also, the Rollins sandstone has been found to have <br />insufficient yield to sustain ground water supply wells <br />(Orchazd Valley Mine MRP). This unit lies 270 feet below the <br />21 <br />