2011-03-14_REPORT - C1982056 (3)

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although the level stabilized in 2000, and continues to be stable through 2010. The historical declining water level trend at well 001-83-107 (Figure 19), continued in 2010. This decline may be attributable to the pumping of well 001-83-106. Well monitoring at 95M001 (Figure 20) indicated a continuing decline in water levels which began in 1997, and appears to have stabilized in 2003. No significant inflows from the Trout Creek formation into the mine workings have been encountered to explain this difference in potentiometric surface or to suggest that dewatering of the formation is directly attributable to mining activities. No readily apparent water quality impacts associated with mining are noted for the Trout Creek Sandstone aquifer based upon data collected during 2010. Mining related dewatering impacts were noted for the Fish Creek sandstone wells 91M00l and 91M004 (Figure 26), and the Ashley well (Figure 27). Wells 91M00l and 91M004 were undermined in 1995 and exhibited historic water level declines corresponding to mining activity. Water levels in these wells subsequently stabilized, exhibiting only seasonal fluctuations. Two springs (SW-1 and SW-2) are monitored in the same vicinity as 91M001 and 91M004. Minor flow was detected in SW=1 during May 2010. SW-2 exhibited no flow in 2010. The Ashley well was undermined in 1999 and exhibited water level declines corresponding to mining activity. This well appeared to be recovering in 2000, continuing through 2010. No unusual observations are noted with respect to Foidel Creek alluvium groundwater levels. The historical increasing conductivity trend in well 001-S-5 (Figure 32) stabilized in 2004, and appears to be increasing again through the end of 2010. • No unusual observations are noted with respect to Fish Creek alluvium groundwater levels. The general water level decline noted in well 006-AY-1 (Figure 34) since 1995, appears to continue in 2010. Overall, fluctuations at this well are insignificant. No other notable water level observations are apparent based upon review of the 2010 data. Field conductivity readings at this well appear stable over the last few years. Two new alluvial wells (AVF-13 and AVF-14) were installed in August 2001, and one (AV-F-15) in June 2002. The only unusual observation made to date were elevated iron concentrations in 2003 and 2004, some of which may be related to subsidence ponding. These levels appear to have returned to those seen with normal seasonal fluctuations. The data base for these sites will require expanding before a complete assessment can be made. Surface Water: Recorded surface water flows for Foidel Creek, Fish Creek, and Trout Creek were generally high in comparison to TLC's historic record. Flooding of Fish Creek was observed in March and April. A stream gage study was initiated by TCC with the aid of a consultant in the fall of 2007, continuing through 2010. This study will continue in the spring, summer and fall of 2011. A discussion of this study, including results for re-evaluating stream rating curves will be included in the 2011 AHR. Conductivity concentrations at site 301, 69, and 1005 on Trout Creek appeared elevated during the spring runoff season in April. This may be the result of upgradient spring runoff flushing through the old P & M mine area. No other water quality impacts of concern were evident at any surface water sites monitored during 2010. • Spoil Springs: Recorded 2010 spoil spring discharges remain negligible and, therefore, did not constitute a significant portion of discharge from the TCC mine area with the potential to impact off-site areas. Discharges 19