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degrees west and dip from 1 to 3 degrees to the northeast. These sediments have been incised by erosion, creating a topography characterized by deep canyons that control drainage patterns which flow into the North Fork of the Gunnison River and eventually into the Colorado River. Geologic studies both in the field and of new large scale, color, aerial photographs do not reveal any folding or faulting in the area. This has also been upheld by the fact that no faulting has yet been encountered in the workings of the Blue Ribbon Mine. The overburden of the Blue Ribbon Mine ranges from a few feet to approximately 1,450 feet. b. Ground Water The largest and most useful alluvial deposits found in the region are associated with the North Fork of the Gunnison River. Smaller, more isolated alluvial deposits are associated with several of the other tributaries of the North fork. Directly adjacent to the Blue Ribbon Mine along Hubbard Creek is a small alluvial deposit. The most continuous sandstone aquifers of any significance in the region are the Rollins Sandstone and the massive sandstone separating the upper and lower coal members of the Mesaverde Formation. However, the latter massive sandstone produces very little water, as evidenced by the dryness of the Bear Mine and the lack of springs associated with this unit. Also, the Rollins Sandstone has been found to have insufficient yield to sustain ground water supply wells (Orchard Valley Mine MRP). This unit lies 270 feet below the F coal seam. Occurrences of ground water have been noted in the Mesaverde Formation from information obtained from drilling, experience in the mines, and from the presence of springs and seeps in the region. This information also indicates that the only potential regional bedrock aquifer in the general area is the laterally continuous Rollins Sandstone. The laterally discontinuous lenticular sandstones within the Upper Mesaverde Formation support only localized ground water flows. Recharge to the Rollins Sandstone occurs along outcrops, along subcrops beneath stream alluvium and in the channels of the North Fork and its tributaries. However, due to the steepness of the topography in the outcrop area (i.e., sandstones are ledge formers) and the narrowness of the stream valleys, these local aquifers receive little recharge. Some recharge to the continuous units and much of the recharge to the more discontinuous, lenticular units will come directly from the percolation of snowmelt and precipitation downward through sandstone lens and along fractures. _21_