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Ground Water Quality Summary. Increasing TDS trends were observed at <br />nine wells downgradient of mining. Four downgradient wells exhibit <br />stable or decreasing TDS trends. The GWPOC well for the Dry Creek <br />Alluvium, DCAL -02, did not exceed the TDS GWPOC standard, 3195 mg /1, or <br />any other standard. <br />In the Probable Hydrological Consequences (PHC, Tab 17) section of the <br />Seneca II -W Mine PAP, predictions were made as to the expected TDS <br />increases to be observed at various monitoring wells. The following <br />table outlines these predictions along with this year's observed average <br />values (annual average for bedrock wells, May- September average for <br />alluvial wells). <br />Well Predicted TDS values (ma /1) <br />WHAL7 -2 <br />1299 <br />WOV14 <br />4385 <br />WOV17 <br />4295 <br />WOV25 <br />none <br />WW14 <br />2630 <br />WW17 <br />3002 <br />WW25 <br />none <br />* indicates <br />value above prediction <br />This year's average TDS (mg /1) <br />630 <br />4760* <br />11,500- <br />2620 <br />5000* <br />660 <br />2880 <br />For Well WOV14, a value of 4385 mg /1 was predicted, while a value of <br />4760 mg /l was observed this year. For Well WOV17, a value of 4295 mg /l <br />was predicted, while a value of 11,500 mg /l was observed in this year. <br />The predicted value for Well WOV17 was predicated on a 5.5% increase of <br />the premining value of 4072 mg /l, which is an average of several <br />overburden wells. However, Well WOV17 exhibited a premining TDS average <br />value of 8043 mg /1, while the next highest TDS Wadge overburden well <br />(WOV15) had a baseline TDS average of 3741 mg /l. Well WOV17 also <br />exhibited a high degree of baseline TDS variability (min. = 6860, max. _ <br />8586 mg /1). The TDS value in this year, 11,500 mg /l, was above the PHC <br />prediction using the average baseline value (8043 + 5.5% = 8485 mg /1), <br />and is also above a 5.5% increase of the maximum baseline TDS value <br />