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A consequence of the use of sediment ponds for treatment of the mine <br />site runoff is the increased concentration of dissolved solids in waters <br />discharged to the receiving streams. It is anticipated that, due to the <br />high dilution ratio of Hubbard Creek to the outflow rates of ponds at <br />the Blue Ribbon Mine, discharges have only minimally increased total <br />dissolved solids (TDS) in Hubbard Creek if at all. No effect has been <br />noted to date. <br />There is no indication that water from Hubbard Creek has been directly <br />flowing through faults into the mine workings, although mine water <br />inflow monitoring ceased when the portals were sealed in 1986. The <br />initial mine workings were above the level of Hubbard Creek. As <br />mining progressed to the north and west, mine workings were <br />developed below the level of the streambed and alluvium of Hubbard <br />Creek. This area of the mine is approximately five acres and is more <br />than 2,000 feet, horizontally, from the Hubbard Creek alluvium. The <br />mine never encountered faults and fractures in this northern area. If <br />faults and fractures are in contact with streambed or alluvium, they <br />would, in turn, provide conduits through which stream water may be <br />routed into the mine workings. The depletion in Hubbard Creek due to <br />mine inflows would not be significant since the area ofthe mine below <br />the level of Hubbard Creek is small. The net depletion of the quantity <br />of water in Hubbard Creek during mining would be zero. However, <br />following mining, there is a possibility that water tributary to Hubbard <br />Creek will continue to be depleted until the mine workings and all <br />dewatering faults, fractures and rock strata below the creek level are <br />filled or recharged. The amount of water involved in the filling of the <br />workings and affected strata will be small, given the limited area of <br />mining below the level of the creek. <br />Subsidence fractures extending to the surface may impact overland <br />surface flow and stream flows in the small ephemeral drainage above <br />the mine workings. This impact to surface water has been negligible <br />due to the small total area of the mine, the steep slopes (60 percent <br />slope, or 30 degrees) and the steep stream gradients encountered in the <br />permit area. The steepness of the slopes and streambeds would favor <br />runoffover infiltration even with subsidence fractures intercepting the <br />surface. <br />Blue Ribbon Coal Company has conducted a spring survey of the <br />permit area. One spring was located within the permit area. This spring <br />is located below the mine bench and discharges from rock strata which <br />are stratigraphically below the E seam. The Blue Ribbon mining <br />operation should have no effect on the quantity and quality of flow in <br />this spring. <br />Impacts from Coal Mine Waste Disposal on Surface Water. The <br />primary concern with regard to the underground coal mine waste <br />25 <br />