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• Subsidence monument surveys disclosed no unusual developments during the reporting period. Projected <br />subsidence magnitudes and draw angles were within the anticipated ranges previously documented for the area. <br />Structures remained essentially unaffected during the period with the exception of the predicted impacts to the <br />Union Pacific Railroad and YVEA power line poles. No adverse impacts, i.e. imminent failure of structure, were <br />evident with regard to these structures. <br />During the summer of 2002, subsidence ponding became evident in the immediate azea of surface site 1002. This <br />azea will be surveyed in 2003. The 14 Rt longwall panels will undermine Fish Creek in November 2002. <br />Potential impacts will be surveyed in 2003. <br />Foidel Creek: has been undernuned and subsided by TCC's mining of the 9 Rt, 8 Rt, 7 Rt, and to a very limited <br />extent the 6 Rt panels, and extreme eastern end of panel 12 Rt. Mining in 12 Rt was completed in 2001, and <br />subsequently sealed in September 2001. Figure 135 provides the location of the creek in relation to the <br />previously mentioned longwall panels. The figure also reflects the ponding that occurred over the panels. As <br />noted on Figure 135, the lazgest area of ponding resulted from mining of 7 Rt. Pond 4 had the greatest surface <br />area, approximately 3 acres, of all of the ponds over the mined area. Field observations indicate that this pond <br />dries up in late summer. It appears that this is due to the fact that the creek is no[ deeply incised and after the <br />completion of spring run-off the flooded areas quickly dries as the creek returns to its historic channel. The 2002 <br />field observations indicated that the area did not flood as extensively as it did in 2000. <br />• No adverse impacts (i.e. imminent failure of stmc[ure) were evident with regard [o these structures. No <br />significant ponding along Foidel Creek, relating to subsidence effects of 12 Rt mining, were observed. Drought <br />conditions in 2002 may have minimized potential impacts. <br />Middle Creek: As shown on Figure 136, Middle Creek Profile Over Panels 2 Rt through 6 Rt, no significant <br />changes to the creek channel were noted. Current survey data shows that no ponds were formed over the mined <br />out panels. <br />5.0 SUMMARY AND CONCLUSIONS <br />No significanUunexpected hydrology impacts, attributable to the activities or developments at the Foidel Creek <br />Mine, were noted during 2002. The previously noted declining water level trend in Wadge Overburden well <br />91 M006 (Figure 9) appears to have continued during 2002. This trend may be related to localized dewatering of <br />the formation as a result of mining activities in the vicinity. The marked decline in water level noted in 1999, in <br />wells 93M001 (Figure 13) and 93M003 before it was abandoned (Figure 15), appears to correspond to longwall <br />mining in the EMD. No significant water quality degradation is noted for the Wadge Overburden formation as a <br />result of evaluating data collected during 2002. <br />• Water levels monitored in the Twentymile Sandstone wells remained stable and comparable to previously <br />collected data, and no significant water quality influences were evident from data obtained during 2002, with the <br />exception of well FBR-11B. Water quality data obtained from this well in April 2002 was comparable to that of <br />15 <br />