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unusually high TDS values (over 10,000 mg/1) were observed at this well. <br />These values were over the pre -mining average, 8043 mg/l, for this well. <br />The TDS value for this well in 2010, 2012, 2013, 2014 and 2015 dropped <br />back down to a value within the 1988-2007 range (3766 to 9580 mg/1). The <br />overall TDS trend for this well is decreasing. <br />The Seneca II -W PHC predicts an annual average TDS value of 2630 mg/l <br />for Wadge Coal Well WW14, while a value of 4895 mg/1 was observed this <br />year. However, for Wadge Coal Well WW17, a value of 3002 mg/l was <br />predicted, while a value of 648 mg/l was observed this year. <br />As noted in the previous paragraph, Well WW14 experienced this year a <br />TDS exceedance of the PHC prediction. This prediction was based on <br />several assumptions. 1) Baseline water quality values were an average of <br />all Wadge coal wells at Seneca II -W. 2) Aquifer characteristics were an <br />average of all Wadge coal wells at Seneca II -W. 3) The Wadge coal seam <br />was saturated for its entire thickness (11.8 feet). These assumptions, <br />however, do not hold true for Well WW14. Prior to mining in the north <br />area (November 1992), this well was almost always dry (see the 1993 AHR <br />for a complete listing of earlier water level data). Since this <br />particular portion of the Wadge seam was dry prior to mining, spoils <br />water will now contribute much of the water present. Also, the average <br />water level this year, 11.71 feet, indicates that additional strata are <br />being saturated, which may also explain the elevated TDS value. <br />Agricultural ground water standards were exceeded this year at certain <br />monitoring wells. Tab 7 of the Seneca II -W PAP contains a section that <br />discusses the suitability of using water from the various aquifers <br />monitored at the Seneca II -W Mine for irrigation or livestock watering. <br />The discussion mentions that, prior to mining, all aquifers at the <br />Seneca II -W Mine exhibited several parameter concentrations in excess of <br />both irrigation and livestock standards, rendering them questionable <br />regarding their suitability for either irrigation or livestock. All <br />bedrock aquifers affected by mining have been determined to have <br />transmissivities less than 100 ft2/day, which would also preclude their <br />use for yielding sufficient water for irrigation, or even livestock. <br />11 <br />