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20 <br />Twentymile Sandstone <br />Elevated pH levels were observed at the wells completed in <br />the Twentymile Sandstone. It appears that the pH observed <br />is within the historic levels identified in Table 08o of the <br />permit. No other impacts were noted by TC. <br />Trout Creek Sandstone. <br />Page 2.05-141.1 of the PHC indicates drawdown in the Trout <br />Creek Sandstone will occur if communication is established <br />with mine workings through fault zones and that this is not <br />expected to occur. However is appears water levels in the <br />Trout Creek Sandstone have drawn down based on the well <br />data for this aquifer. TC indicates that the decline in water <br />levels in the Trout Creek Sandstone at well 001-83-106 is <br />likely due to pumping at this well for domestic use at the <br />mine. TC believes that significant inflow from the Trout <br />Creek Sandstone into the mine working have not been <br />encountered to date. However, TC also indicates that <br />declines in water well 001-83-006 may be attributed to <br />longwall mining that began in the western mining district in <br />1990 in addition to the water well use. TC indicates that a <br />drop in water level at well 97013TC occurred in mid -2010 <br />which is the result of being mined through. <br />Given these observations, it does not appear the PHC is <br />correct. It appears drawdown is occurring in the Trout <br />Creek Sandstone and the PHC and the AHR appear to <br />contradict whether or not mining is the cause of this <br />drawdown. The PHC will need to be updated to address <br />the drawdown of this aquifer and negative impacts <br />assessed. <br />Foidel Creek Alluvium <br />The PHC indicates that mine discharge water will impact <br />Foidel Creek and its alluvium. <br />-Well 008 -AV -2 <br />• The manganese levels reported on August 18, 2014 <br />20 <br />