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• previous years, however water quality from a second water sample at the end of 2002 indicated new historic maximum conductivities (]ab & field), new historic minimum pH (lab & field), as well as new maximums for TDS, sodium, bicarbonate, sulfate, and manganese. Information from TCC's consultant, Miller Water Monitoring, combined with analytical data, suggests that well FBR-11B may be damaged, and that water may be infiltrating from another source (e.g. shallow alluvium), accounting for the change in water quality. It might be speculated that well FRR-11B has been impacted by subsidence effects from [he 13 Rt longwall panel. Further investigation will be conducted in the spring of 2003, prior to the next required monitoring episode. Localized dewatering of the Trout Creek Sandstone appears evident.in the vicinity of well 001-83-106 (Figure 29), although the level started recovering slightly in 1999, and continues in 2002. The historical declining water level trend at well 001-83-107 (Figure 30), is continuing in 2002. This decline may be attributable to the pumping of well 001-83-106. Well monitoring at 95M001 (Figure 31) indicated a continuing decline in water levels which began in 1997. 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 appazent water quality impacts associated with mining aze noted for the Trout Creek Sandstone aquifer based upon data collected during 2002. Mining related dewatering impacts were noted for the Fish Creek sandstone wells 91M001 and 91M004 (Figure 40), and the Ashley well (Figure 41). Wells 91M001 and 91M004 were undermined in 1995 and exhibited 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) aze monitored in the same vicinity as 91M001 and 91M004. Neither of these springs flowed during 2002. The Ashley well was undermined in 1999 and exhibited water level declines corresponding to mining activity. This well appeazed to be recovering in 2000, and continues in 2002. TCC will continue to monitor these locations in 2003. No unusual observations aze noted with respect to Foidel Creek alluvium groundwater levels. The historical increasing conductivity trend in well 001-S-5 (Figure 46) appears to be continuing in 2002. A trend showing a slight increase in TDS concentrations at Foidel Creek alluvium at well 008-AV-2 (Figure 51) appears to be continuing in 2002. TCC will continue to monitor the direction of this trend. 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 56) since 1995, appears to continue in 2002. Overall, fluctuations at this well are insignificant. No other notable water level observations aze appazent based upon review of the 2002 data. Field conductivity readings at [his well appear stable over the last few years. Two new alluvial wells (AVF-13 and AVF-14) were installed in August 2001, and one (AVF-15) in June 2002. No unusual observations have been made to date, however, the data base for these sites will require expanding before general observations can be made. Monitoring was initiated on trout Creek Alluvial wells back in 1994. In 2002, one Trout Creek Alluvial well • (Jones Well -Table 36) new maximum values were recorded for dissolved magnesium, dissolved sodium, bicazbonate, and sulfate for a sample collected on March 7, 2002. An evaluation of data for surface sites that might have contributed to these new maximum values was conducted. The following was noted. During the 16