2017-03-15_REPORT - C1981010 - Laserfiche WebLink

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However, some of this higher level could be natural based on natural large concentrations observed in 2nd White Sandstone well P-5. Concentrations are expected to decline in the future if the increase is due to upgradient mining. Figure B-6 also presents TDS values for 2nd White Sandstone well P-5 and shows that the concentration were in the 2500 to 3000 mg/1 range prior to mining in this area and were similar to these values in the most recent samples. Natural water -quality concentrations in the 1st, 2nd and 3rd White Sandstones are expected to vary over a similar range. Figure B-7 presents the TDS concentrations versus time for alluvial wells GC -3, P-1, J-1 and COY. TDS concentrations in Pyeatt alluvial well P-1 were variable in 2016 and similar but slightly higher than historical levels. The TDS concentrations in alluvial ground water in Johnson Gulch (J-1) had been fairly steady since 2000 but very gradually increased the last four years. The recent Johnson Gulch alluvial ground water is within the natural range for TDS in this aquifer. These TDS values and variations are very similar but slightly higher than natural values observed in Flume Gulch alluvial well, COY. Flume Gulch has two alluvial monitoring wells, GC -3 and COY. TDS concentrations overall have been steady in well GC -3 with variations observed the last few years similar to previous values. The 2016 TDS concentrations in the COY well were similar to higher natural values in this well. The TDS concentrations in the COY well and historical variations in well P-1 show that recent Johnson alluvial TDS concentrations are slightly higher than natural alluvial concentrations in the alluvial aquifers in this area. The natural variability in surficial alluvial aquifers in this area is large and the upper limit may have not been fully defined by historical measurements. Trapper Mining Company 3-4 2016 Annual Report