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-30- During mining, the applicant projects that the quality of mine inflow waters will be similar to the qualities of mine inflows encountered in the The applicant, Middle Creek underground mine and the Empire Energy Corporation Eagle ~o. 5 and No. 9 mines. These mines, during operation, have mine waters with TDS levels which average around 800 mg/1. These three mines probably receive a significant percentage of their inflows from overlying surface stream alluvial systems, which tend to dilute the poorer quality ground waters in the rock aquifers. The Foidel Creek underground mine does not underlie similar stream alluvial systems, and, therefore, mine inflow water qualities will probably be similar to the qualities of ground waters in the affected rock aquifers. After the mining operations have ceased at the Foidel Creek underground mine, degraded mine and spoils waters will enter 1) the rock strata affected by mining (i.e., the coal, floor, and roof strata in the zone of subsidence), and 2) the fault and fracture systems encountered during mining. The underground mine, upon cessation of mining, will contain fractured roof and coal strata, and exposed floor strata. Also, the mine inflows will continue until the mine workings are filled, or an equilibrium is reached between the mine inflow rate and the discharge rate through affected strata, faults and fractures. The inflow waters will pick up soluble ions due to the leaching and weathering of the exposed and fractured rock strata. Some of the inflow water will be spoils waters from the adjacent Energy No. 1 and Eckman Park Mines, which mined the Wadge coal seam by surface methods and which have the same exposed strata at their northernmost (downdip) limit. The increased permeability of the abandoned underground mine workings will tend to move the point source of degraded mine and spoils waters downdip, closer to the center of the Twentymile Park Synclinal Basin and closer to the discharge points of the affected strata, faults and fractures. Some of the degraded ground water may discharge from the basin through the Nayden Syncline to the Sandwash Basin. Some may discharge directly to the Fish Creek surface system through faults and fractures. finally, some may enter the Fish Creek surface alluvial system through springs and seeps from outcrops and subcrops of the affected strata. A quantification of the time of travel to discharge points on Fish Creek was made by the applicant. The applicant, using a plume management model, predicts that the pollutant plume will take over 500 years to reach the discharge paint after hydrostatic heads have reached pre-mining levels. The advancing pollutant plume will become diluted through diffusion and dispersion enroute. The resulting discharge rate at the Wadge coal-overburden aquifer discharge point on Fish Creek is projected to be similar to pre-mining conditions (0.14 cfs). The resulting increased salt load to Fish Creek, therefore, is a future effect that will not be significant.