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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 average TDS (mg/1) <br />924 <br />3960 <br />4750* <br />1610 <br />4790* <br />624 <br />600 <br />For Well Wadge Overburden WOV17, a value of 4295 mg/l was predicted, <br />while a value of 4750 mg/l was observed in this year. The predicted <br />value for Well WOV17 was predicated on a 5.54 increase of the pre -mining <br />(prior to August 1990 for the central area) value of 4072 mg/l, which is <br />an average of several overburden wells. However, Well WOV17 exhibited a <br />pre -mining TDS average value of 8043 mg/1, while the next highest TDS <br />Wadge overburden well (WOV15) had a baseline TDS average of 3741 mg/1. <br />Well WOV17 also exhibited a high degree of baseline TDS variability <br />(min. = 6860, max. = 8586 mg/1). The TDS value in this year, 4750 mg/l, <br />was below the PHC prediction using the average baseline value (8043 + <br />5.5% = 8485 mg/1) and is below a 5.54 increase of the maximum baseline <br />TDS value (8586 + 5.54 = 9058 mg/1). In 2008, 2009 and 2011, unusually <br />high TDS values (over 10,000 mg/1) were observed at this well. These <br />values were over the pre -mining average, 8043 mg/l, for this well. The <br />TDS value for this well in 2010, 2012, 2013, 2014, 2015, 2016 and 2017 <br />dropped back down to a value within the 1988-2007 range (3766 to 9580 <br />mg/1). The overall TDS trend for this well is decreasing. <br />10 <br />