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operation of the water supply well and the operation of the augmentation reservoir are not anticipated to have any discernable effects upon the hydrologic balance of Hubbard Creek or the use of Hubbard Creek water downstream. The anticipated impacts of the Blue Ribbon Mine on the quality of water flowing in Hubbard Creek are minimal. There is also expected to be no interruption of the quantity of water flowing to Hubbard Creek. Surface flows from disturbed areas are routed through sediment ponds designed to discharge water meeting the effluent limitations of Rule 4.05.2(7). The surface disturbed area associated with the Blue Ribbon Mine is approximately 20 acres, or about 0.1 percent of the drainage area of Hubbard Creek, excluding those areas of upstream diversion. The actual production of water from the surface affected area of the Blue Ribbon Mine will be somewhat less than 0.1 percent of the flow in Hubbard Creek due to the direct relationship of water yield to elevation. Therefore, assuming that all runoff water from the mine is lost through evaporation in sediment ponds (worst case), a loss of less than 0.1 percent of Hubbard Creek yields is expected. A consequence of the use of sediment ponds for treatment of the mine site runoff is the increased concentration of dissolved solids in waters discharged to the receiving streams. It is anticipated that, due to the high dilution ratio of Hubbard Creek to the outflow rates of ponds at the Blue Ribbon Mine, discharges will only minimally increase total dissolved solids (TDS) in Hubbard Creek. Since the mine workings are above the level of Hubbard Creek, the mine presently does not experience any inflows which can be directly related to the water flowing in Hubbard Creek. As mining progressed to the north and west, mine workings are now located below the level of the streambed and alluvium of Hubbard Creek. This area of the mine is approximately five acres and is more than 2,000 feet, horizontally, from the Hubbard Creek alluvium. The mine may encounter faults and fractures in this northern area. If faults and fractures are in contact with streambed or alluvium, they would, in turn, provide conduits through which stream water may be routed into the mine workings. The depletion in Hubbard Creek due to mine inflows would not be significant since the area of the mine below the level of Hubbard Creek is small, and since the water made in the mine would most likely be consumed within the mine or pumped to the surface. The use of mine inflow water would, in turn, reduce the amount of water now being pumped from the well in the Hubbard Creek alluvium. The net depletion of the quantity of water in Hubbard Creek during mining would be zero. However, following mining, _27_