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the Williams Creek and Ward Creek valleys. Groundwater movement in the permit area discharges to the stream/alluvial aquifer system. Mining will dewater adjacent portions of the coal seam aquifer and will intercept some of the groundwater currently discharging to the stream/alluvial aquifer system. In addition, the presence of the underground workings beneath the valley could reverse the pre-existing groundwater flow direction between the valley and the mine workings, and water from the stream/alluvial aquifer system could enter the mine workings through the coal seams. This reversal of ground water flow direction would occur only in areas where the coal seams are fractured. The applicant has provided a prediction of inflow to the mine for the D and E coal seams on a yearly basis. The maximum predicted inflow, 78.67 gpm (0.17 cfs) in 1983, provides an estimate of worst-case streamflow depletion. One-third of the measurable mine inflows in the E seam mine were found in the area below Ward Creek. Little inflow was observed below Williams Creek. The effect will be temporary, since once the workings become flooded, discharge will once again be to the surficial aquifer via the su be rop. Since some of the ground water inflow comes from other sources, such as depletion of ground water storage, the actual stream flow depletion would probably be less than predicted. Actual inflow in Mine No. 1 (E-Seam) never exceeded 25 gpm. The applicant's modeling estimates that two years after ground water removal begins, the total volume of water intercepted by the mine would be taken directly from the stream. The addendum reports that the minimum streamflow observed in Ward Creek by the ditch rider was 2.5 cfs in 1977. Therefore, the total mine inflow (and worst-case streamflow depletion) represents only 7 percent of the lowest streamflow observed in Ward Creek. The predicted mine inflow is only about 2 percent of the average flow in Ward Creek. During operations, most of the mine water was returned to the Ward Creek drainage system. Mine water was pumped to a sediment pond, where water not lost to evaporation was discharged to the Ward Creek system via Carbon Ditch. Mine water had a degraded water quality with an average conductivity of 3.5 mmhos/cm and was expected to affect water quality in Ward Creek. Average total dissolved solids (TDS) levels in Ward Creek increased from 99 mg/1 to 194 mg/1. Since the cessation of mining operations, mine water is no longer being pumped from the underground workings. As a result, the mine workings would eventually fill with water, and the natural flow pattern would be restored. Groundwater passing through the abandoned workings would eventually discharge to the glacial/alluvial aquifer. Water passing through the mine workings would be expected to have a 22