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Ground Water Quality Summary. Increasing TDS trends were observed at <br />eight wells downgradient of mining. Five 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/l. <br /> <br />• <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 (mg/1) <br />WHAL7-2 1299 <br />WOV14 4385 <br />WOV17 4295 <br />WOV25 none <br />WW14 2630 <br />WW17 3002 <br />WW25 none <br />* indicates value above prediction <br />This year's averaqe TDS (mq11) <br />1150 <br />4710* <br />6520* <br />2470 <br />5260* <br />750 <br />2610 <br />For Well WOV14, a value of 4385 mg/l was predicted, while a value of <br />4710 mg/l was observed this year. <br />For Well WOV17, a value of 4295 mg/1 was predicted, while a value of <br />6520 mg/l was observed in this year. The predicted value for Well WOV17 <br />was predicated on a 5.5% increase of the premining value of 4072 mg/l, <br />which is an average of several overburden wells. However, Well WOV17 <br />exhibited a premining TDS average value of 8043 mg/1, while the next <br />highest TDS Wadge overburden well (WOV15) had a baseline TDS average of <br />3741 mg/l. Well WOV17 also exhibited a high degree of baseline TDS <br />variability (min. = 6860, max. = 8586 mg/1). The TDS value in this year, <br />6520 mg/l, was below the PHC prediction using the average baseline value <br />(8043 + 5.5% = 8485 mg/1), and is also below a 5.5% increase of the <br />maximum baseline TDS value (8586 + 5.5% = 9058 mg/1). In 2008 and 2009, <br />9