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fluctuations in the concentrations of some analytical parameters (e.g. iron, conductivity, TDS, etc.) do occur at <br />the surface sites. Increases in iron concentration are often related to accumulation and leaching of iron - bearing <br />strata/sediments during spring runoff. Some elevated iron concentrations may also be related to ponding effects <br />(e.g. increased solids in ponded samples) <br />In 2011, subsidence did occur from mining on the new Western Mining District, such as along County Road 79. <br />However Fish Creek was not subsided in 2012. <br />Foidel Creek: was historically undermined and subsided by TC's mining of the 9 Rt, 8 Rt, 7 Rt, and to a very <br />limited extent, the 6 Rt panel, and extreme eastern end of panel 12 Rt. Mining in 12 Rt was completed in 2001, <br />and subsequently sealed in September 2001. No significant changes to the creek channel were noted in 2012. <br />Middle Creek: was historically undermined and subsided by TC's mining of the 2 through 6 RT. No ponds <br />were formed over the mined out panels. Mining in 6 RT was completed in 2000. No significant changes to the <br />creek channel were noted in 2012. <br />5.0 SUMMARY AND CONCLUSIONS <br />No significant hydrology impacts, attributable to activities at the Foidel Creek Mine, were noted during 2012. <br />See discussion below, summarizing data assessments. <br />Water Wells: Water levels monitored in the Twentymile Wadge Overburden wells remained stable and <br />comparable to previously collected data, and no significant water quality influences were evident from data <br />obtained during 2012. <br />Twentymile Sandstone wells remained stable and comparable to previously collected data, and no significant <br />water quality influences were evident from data obtained during 2012. Localized dewatering of the Trout Creek <br />Sandstone appears evident in the vicinity of the TC potable water well 001 -83 -106 (Figure 18), although the level <br />stabilized in 2000, and continues to be stable through 2012. The historical declining water level trend at well <br />001 -83 -107 (Figure 19), continued in 2012. This decline may be attributable to the pumping of well 001-83-106. <br />Well monitoring at 95M001 (Figure 20) indicated a continuing decline in water levels which began in 1997, and <br />appears to have stabilized in 2003. No significant inflows from the Trout Creek formation into the mine <br />workings have been encountered to explain this difference in water level or to suggest that dewatering of the <br />formation is directly attributable to mining activities. No readily apparent water quality impacts associated with <br />mining are noted for the Trout Creek Sandstone aquifer based upon data collected during 2012. <br />Mining related dewatering impacts were noted for the Fish Creek sandstone wells 91M001 and 91M004 (Figure <br />26), and the Ashley well (Figure 27). Wells 91M001 and 91M004 were undermined in 1995 and exhibited <br />historic water level declines corresponding to mining activity. Water levels in these wells subsequently stabilized, <br />exhibiting only seasonal fluctuations. Two springs (SW -1 and SW -2) are monitored in the same vicinity as <br />91M001 and 91M004, although neither of the springs flowed in 2012. The Ashley well was undermined in 1999 <br />and exhibited water level declines corresponding to mining activity. This well appeared to be recovering in 2000, <br />continuing through 2012. <br />17 <br />