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The North Thompson Creek Mines are impacting the quantity and quality of <br />ground water in the North and Middle Thompson Creek drainage basins. <br />These impacts are minimal, at present. <br />Both the North Thompson Creek No. 1 and No. 3 Mines are experiencing <br />mine inflows. The inflow maps, descriptions of inflows, and water quality <br />analyses of inflows are within the permit document. The inflow water quality <br />analyses indicate at least two sources of water. The inflows with low total <br />dissolved solids (TDS) concentrations have water qualities similar to surface <br />waters. This suggests that these inflows may be transmitted directly [o the <br />mine workings from the surface water system with very little residence time <br />in the transmitting aquifer. These low TDS inflows are also generally found <br />emanating from fractures beneath or directly adjacent to the stream valleys of <br />North and Middle Thompson Creeks. High TDS inflows indicate longer <br />residence time and reactive time with soluble minerals in the transmitting <br />aquifer. These inflows represent the dewatering of overlying and underlying <br />aquifers whose ultimate source of recharge cannot readily be determined. <br />The impacts of depleting ground water in overlying and underlying aquifers <br />were predicted to be minimal as long as these aquifers do not add significantly <br />to the depletion of springs and stream flows. <br />The depletion of ground water from aquifers may impact the discharge of <br />over- and underlying aquifers by drying up springs and seeps. The applicant <br />has identified only two springs, SP-1 and SP-2, in the petmit and adjacent <br />areas. The drying up of these springs will slightly reduce surface flow during <br />high flow periods and also improve water quality, as these springs are <br />intermittent and have poor water qualities. The net impact of drying up these <br />springs will be minimal and even beneficial, because the water quality of <br />these springs is poor. <br />The depletion of bedrock ground water in the mine area did not impact any <br />wells within the permit and hydrologically adjacent areas. Water depleted <br />from ground water aquifers was replenished after closure of the mine. The <br />depletion continued until the mine workings filled and an equilibrium was <br />established between the mine workings and the overlying and underlying <br />strata. <br />All underground mines that induce subsidence have the potential to increase <br />mine inflows, particularly if the subsidence occurs within a significant source <br />of water (e.g., stream, pond, alluvial aquifer). However, coal mine <br />subsidence does not seem to be a source of significant inflows into the North <br />Thompson Creek Mines. Areas which have undergone longwall and pillar <br />extraction (e.g., areas of controlled subsidence) do not contribute significant <br />inflows. This can be attributed to the fact that these mine areas are not under <br />is <br />