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changes in water levels were noted. More data will be needed to <br />determine if these values were anomalies. However, the elevated TDS <br />values may not be attributed to spoil water. The maximum TDS value for <br />spoil springs upgradient of this well in 2009 was 4490 mg/1, and <br />exhibited a CaMg-SO4 type water. <br />- Wadge Coal. Three wells monitor the Wadge coal seam. North area Well <br />WW14 exhibits an increasing TDS trend. Middle area Well WW17 exhibits a <br />nearly level TDS trend. South area Well WW25 was drilled in September <br />2004. TDS values at this well display an increasing trend. <br />The Seneca II-W PHC predicts an annual average TDS value of 2630 mg/l <br />for Well WW14, while a value of 5310 mg/l (4930 mg/l calculated) was <br />observed this year. For Well WW17, a value of 3002 m.g11 was predicted, <br />while a value of 660 mg/l was observed this year. <br />As noted in the previous paragraph, Well WW14 exper_Lenced this year a <br />TDS exceedence 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). <br />These assumptions, however, do not hold true for Well WW14. Prior to <br />mining in the north area (November 1992), this well was almost always <br />dry (see the 1993 AHR for a complete listing of earlier water level <br />data). Since this particular portion of the Wadge seam was dry prior to <br />mining, spoils water will now contribute 100% of the water present. <br />- Sage Creek Overburden. This unit exits between the Wadge and Wolf <br />Creek coal seam. Mining of the Sage Creek coal seam began in September <br />2003. Well WSOV24 was drilled in August 2001 in the II-W South area. <br />Only five samples were collected until this well failed due to a <br />landslide that occurred in April 2003. A replacement well, WSOV25, was <br />drilled in September 2004. TDS values at this well display a decreasing <br />trend from 2007's value (SF 0.5). All values have been below 800 mg/1. <br />7