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expected for the 3rd White Sandstone and is likely due to the upgradient mining based on • <br />the timing and magnitude of the increase. However, some of this higher level could be <br />~, <br />natural based on natural large concentrations observed in 2nd White Sandstone well P-5. <br />Concentrations are expected to decline in the future if the increase is due to upgradient <br />mining. <br />Figure B-8 presents TDS values for 2nd White Sandstone well P-5 and shows that <br />the concentration has been in the 2500 to 3000 mg/I range prior to mining in this area. <br />Natural water-quality concentrations in the 1st, 2nd and 3rd White Sandstones are <br />expected to vary over a similar range. Figure B-8 also presents 2nd and 3rd White <br />Sandstone well GE-3 and 1st White Sandstone well GLUX-1, which consists of low 7DS <br />water. <br />Figure B-9 presents the 7DS concentrations versus time for alluvial wells GC-3, P-1, • <br />J-1 and Coy. Lewis Shale well P-3 is also included in this plot due to its response to the <br />Pyeatt alluvial system. The TDS in well P-3 has increased over the last three years in the <br />shallow aquifer to a concentration similar to the maximum historically observed value. TDS <br />concentrations in Pyeatt alluvial well P-1 have also increased the last few years as <br />expected for a shallow ground-water system but these variations are within the historical <br />natural range. <br />The ailwial ground water in Johnson Gulch has shown an increasing trend in TDS <br />since 1996. The 2000 Johnson Gulch alluvial ground water is still within the natural range <br />for 7DS in this aquifer. These TDS values and variations are very similar to the natural <br />values and variations observed in Flume Gulch alluvial well, COY. <br />• <br />3-4 <br />