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-55- Probable Hydrologic Consequences - Bear Coal Effects of the Bear Coal Company Mining operation on Ground Water Faults and fractures intercepted during the Bear Mining operation could produce mine inflows, as is the case in other mines in the North Fork Basin. Any inflows which may occur are expected to be minor, based on mining of the C seam in the Bear No. 1 and No. 2 and previous mining of the C seam in the old Edwards mine, which has resulted in minor inflows. Apparently, the massive sandstone which caps the lower coal member produces very little water. These mines have not discharged mine water, but have imported water into the mines for underground use. There is a possibility that water existing in the Rollins Sandstone or other sandstones below the C seam could appear as mine inflows from the floor, through faults or fractures penetrating the lower strata, or produce floor heaving. Floor seeps have not been encountered in any of the three Bear mines. Floor seeps have occured in other mines in the area. Mine inflows of 10 gpm have been reported, associated with the D seam floor at the Orchard Valley mine, near Paonia. The only other bedrock aquifers in the general area, above the Bear mines, are the saturated Ieuticular sandstones in the Barren member above the F seam. The C seam is separated from the Barren member by over 300 feet of sedimentary strata. No impact on the hydrologic functions of the Barren member aquifers, including springs supplied by those aquifers is anticipated. A stipulation has been included in Section V of this document to insure that any mine discharges, will be controlled and treated to meet applicable water quality standards. Effects of mining on the alluvial aquifer of the North Fork of the Gunnison are expected to be insignificant, and are discussed in the Alluvial Valley Floor Section (VII) of this document. Disturbance to the alluvium will be limited to construction and operation of surface facilities and coal storage. No underground development waste will be stored on the surface. No coal processing waste will be produced. A portion of the water used in the Bear No. 3 mining operation may come from the alluvium of the North Fork. This would cause only a localized draw down in the alluvial water table, since the alluvium has a high transmissivity, and the well will be located in close proximity to the river. Thus the Bear operation will have little if any impact on alluvial ground water use in the area. The underground workings of the Bear No. 3 mine will not extend to the south of the ground water and topographic divide referred to in the "Regional Geology and Ground Water Hydrology" portions of this section. Therefore, there is no potential that the Bear mine will affect Barren member ground water or surface water in the Minnesota Creek Drainage. For a description of the extent of mine workings at the Bear No. 3, see Attachment No. 1, "U. S. G. S. Findings".