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The results of the two tests indicate that the hydraulic conductivities of the sandstones below <br />the coals to be mined are lo~v and variable. Because the hydraulic conductivities are low, <br />tittle groundwater is transmitted through the sandstones and discharged to the surface as <br />springs or as base-flow in creeks. Groundwater that is encountered on the property moves <br />extremely slowly. <br />Recharge and Discharue_ <br />Aquifer tests conducted on the two Taylor Creek wells revealed low average hydraulic <br />conductivities for the sandstones. Because the hydraulic conductivity values are relatively <br />low, recharge rates are also low. Recharge to a groundwater system can be estimated by <br />determining discharge from that groundwater system. The U. S. Geological Survey (USGS) <br />installed a continuous recording stream gage at the mouth of Goodspring Creek. Analysis of <br />the data reveals that the average groundwater discharge over the entire Goodspring Basin is <br />on the order of 0.2 to 0.35 inches per year. Since over a long period of time groundwater <br />recharge equals groundwater discharge, the recharge rates for the Taylor Creek Basin are also <br />on the order of 0.2 to 0.35 inches per year. These recharge rates are 1.0 to 1.5 percent of the <br />annual precipitation across the property. These are relatively low values, but the total runoff <br />measured at the USGS gage is only 2.6% of the annual precipitation. <br />This recharge rate includes groundwater recharged to the alluvial aquifer of Goodspring <br />Creek and groundwater recharged to deeper sandstones below the elevations of Goodspring <br />Creek. Because no appreciable quantities of water were observed to be discharging from [he <br />upper sandstones on the mine property and because no appreciable quantities of groundwater <br />were observed during the drilling operations, the calculated recharge rate for the Goodspring <br />Basin is probably closer to an estimate of recharge to the alluvium materials in the valley of <br />Goodspring Creek. Recharge rates of the sandstones that contribute to Goodspring Creek are <br />probably considerably less. <br /> <br />2.04.7-11 <br />