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The results of the two tests indicate that the hydraulic <br />conductivities of the sandstones below the coals to be mined are <br />low and variable. Because the hydraulic conductivities are low, <br />little groundwater is transmitted through the sandstones and <br />discharged to the surface as springs or as base flow in creeks. <br />Groundwater that is encountered on the property moves extremely <br />slowly. <br />Recharoe and Discharge <br />Aquifer tests conducted on the two Taylor Creek wells revealed low <br />average hydraulic conductivities for the sandstones. Because the <br />hydraulic conductivity values are relatively low, recharge rates <br />are also low. Recharge to a groundwater system can be estimated by <br />determining discharge from that groundwater system. The U. S. <br />Geological Survey (USGS) installed a continuous recording stream <br />gage at the mouth of Goodspring Creek. Analysis of the data <br />reveals that the average groundwater discharge over the entire <br />Goodspring Basin is on the order of o.2 to 0.35 inches per year. <br />Since over a long period of time groundwater recharge equals <br />groundwater discharge, the recharge rates for the Taylor Creek <br />~• Basin are also on the order of 0.2 to 0.35 inches per year. These <br />recharge rates are 1.0 to 1.5 percent of the annual precipitation <br />across the property. These are relatively low values, but the <br />total runoff measured at the USGS gage is only 2.6$ of the annual <br />precipitation. <br />This recharge rate includes groundwater recharged to the alluvial <br />aquifer of Goodspring Creek and groundwater recharged to deeper <br />sandstones below the elevations of Goodspring Creek. Because no <br />appreciable quantities of water were observed to be discharging <br />from the upper sandstones on the mine property and because no <br />appreciable quantities of groundwater were observed during the <br />drilling operations, the calculated recharge rate for the <br />Goodspring Basin is probably closer to an estimate of recharge to <br />the alluvium materials in the valley of Goodspring Creek. Recharge <br />rates of the sandstones that contribute to Goodspring Creek are <br />probably considerably less. <br />,• <br />2.04.7-11 <br />- l -_-- - r-= - _ r_- c~.~~--._. __ - _. <br />