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lowered to the 6612 ft elevation level. Well FBR-2-E (Figure 34) continued to exhibit water levels azound the 6665 ft elevation during 2001, which is similar to the previous two water years. Well 001-83-107 (Figure 30) continued to show lower water levels than those typical prior to 1992. Water levels in well 001-83-106 (Figure 29) continue to increase as seen during the previous two water years. Well 95M001 (Figure 31) wntinues to decline, with water levels around the 6420 ft elevation, an historical low, during 2001. The exact reason for this decline is unknown It might be speculated that water is infiltrating more porous/fractured zones above dre Trout Creek Sandstone aquifer via the annulus area surrounding the well casing. Well 97012TC (Figure 36) continued the steady decline apparent since monitoring began in the 1998 Water yeaz. We1197013TC (Figure 38) continued to show the minor fluctuations appazent since monitoring began in the 1998 Water year. Field measurements are presented in Tables 15 and 16 for wells 001-83-107 and 00875-EFC. Field parameter measurements on these Trout Creek Sandstone wells monitored during 2001 returned values within anticipated ranges with no mine related impacts evident. Field measurements and water quality parameters for wells OOI-83- 106, 95M001, FBR-2-E, 97012TC, and 97013TC are provided on Table 14, and Tables 17 through 20. At well 001-83-106 (Table 14) no new minimum or maximum values were noted. The historically elevated pH readings for 001-83-106 have moderated slightly. At well 95M001 (Table 17) new minimum values were recorded for dissolved magnesium. New maximum values were recorded for lab pH, and carbonate. The 2001 pH readings continue to be relatively high at this site. At well FBR-2-E (Table 18) new minimum values were recorded for field pH. High pH readings appear typical for this well also. Wells 97012TC (Table 19) and 97013TC (Table ZO) established some new maximum and minimum values for tested parameters in 2001, due to the limited period • for which values have been collected at these sites. However, none of these values fell outside the typical historical range of other wells in this aquifer. Fish Creek Sandstone: Two Fish Creek Sandstone wells (91M001 and 91M004) were abandoned late in 2000. These wells had previously required monitoring for water levels on a quarterly basis. An additional well (Ashley) required semi-annual monitoring for water levels and field parameters, and annual water quality sampling. These requirements were met during 2001. Tables 21, 22, and 23 provide summazies of the 2001 Water Yeaz data collected at each site. Figure 40 provides graphical representation of the period of record water levels measured at sites 91M001 and 91M004. Water levels a! the Ashley well (Figure 41) dropped appreciably after subsidence, but have continued to recover since 1998. Field measurements and water quality parameters for the Ashley well are provided on Table 23. This well established several new maximum and minimum values for tested pazameters in 2001, due to the limited period for which values have been collected. However, none of these values fell outside the typical historical range of other wells in this aquifer. 3,2 Alluvial Groundwater Monitoring Alluvial ground water in the Twentymile Pazk Basin exists under unconfured conditions within the alluvial materials underlying the major surface drainages of the area and backfilled areas of adjacent surface mined areas. Stream flows are the primary source of recharge to the alluvial aquifers. Alluvial deposition is limited in areas • where stream gradients are relatively steep and in areas where the stream channel has eroded to or intersects resistant bedrock. Consequently, the alluvial deposits do not tend to be continuous. Shallow wells completed in G