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-34- The underground workings of the Bear No. 3 mine and the additional permit area in the revision, does 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. The workings in the permit revision area are not beneath any springs, ponds or any other water source for which a water right has been filed. The mine plan calls for limited extraction in the area of Lone Pine Gulch to ensure this ephemeral drainage is not affected. The Bear No. 3 mine plan is designed to minimize the impacts of the project on the surface water hydrology of the region. The surface disturbance at the Bear No. 3 is limited to approximately 8 acres. Drainage from the disturbed area is routed to a sediment pond and will meet NPDES permit requirements prior to discharge. All discharges are monitored for pH, total suspended solids (TSS), total dissolved solids, iron, manganese, and oil and grease content. The 19 acre disturbed area at the Bear No. 1 and No. 2 portals will be revegetated in the fall of 1985, and runoff rates and quality of runoff from the area should approximate that from adjacent areas in succeeding years. The hydrologic consequence of the Bear mine operation on the North Fork of the Gunnison are minimal. For a detailed discussion of the potential impacts on surface water in the permit and adjacent area, please see the Section VII, Alluvial Valley Floors. CUMULATIVE HYDROLOGIC IMPACT ASSESSMENT Impacts on Ground Water The six underground mines along the North Fork of the Gunnison may impact ground water quantity by one or more of the following: - induced inflows into the mines through faults and fractures which provide communication between the mine and overlying and underlying aquifers and surface waters; - dewatering of the coal, roof and floor with the advance of mining; and, - subsidence-induced flows into the mines. Faults and Fractures Faults and fractures which cut the bedrock strata produce a localized increase in secondary permeability within the strata. If the faults and fractures do not become sealed by clays, they may become conduits for the flow of ground and surface water. When encountered within the mine, faults and fractures will dewater. The amount of water flowing into the mine from these sources depends on porosity and permeability of faults or fractures, and on the open vertical connection within the faults and fractures between the coal seam and sources of ground or surface water.