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. collected data at well 001-83-106 with Tables 17a through 20a providing the period of record statistical summaries of collected data a[ wells 9~M001, FBR-2-E, 97012TC a,td 97013TC. Figures 39 through 39 provide graphical representations of water levels and selected water quality parameters recorded at each site. The continuous pumping of well 001-83-106 (Figure 29) complicates the potentiometric surface in the Trout Creek Sandstone. The potentiometric surface trends prevalent in the Twentymile Sandstone and Wadge Overburden aquifers are not evident in the monitored Trout Creek wells. The previously monitored well 006-83- 48C routinely ex}tibi[ed water levels in the 7100 ft elevation range while replacement well FCM#2 returned levels around elevation 620 during 1995. In the fall of 1995, well 95M001 was established in part [o address dte apparent discrepancy in water levels between wells 006-83-48C and FCM#2. Water levels rehtmed from well 95M001 confirm that levels recorded from well FCM#2 were accurate (Figure 31). InFlon•s from the Trout Creek Sandstone into the mine workings have not bezn encountered to date to account for [he apparent lowering of the potentiometric surface in the Trout Creek formation as indicated by [he water level data previously recorded for well 006-83-48C. Some dewatering of [he aquifer does occur from [he pumping of well 001-83-106 to supply the mine with domestic water. During 1999, the southernmost Trout Creek well (001-83-107 -Figure 30) continued to exhibited lower water levels in the 6850 ft elevation range while the northernmost well (008-7i-EFC -Figure 32) remained around the 6620 ft elevation level. Well FBR-2-E (Figure 30) returned levels around 6670 ft elevation during 1999, which is appreciably lower than [hz historical level of 6720 ft. Well 95M001 (Figure 31) returned levels around 6460 ft elevation during 1999, which is appreciably lower than the historical level of 6510 ft. Well 001-83-107 continued to show lower water levels than those typical prior ro 1992. Well 001-83-106 remains drawn down presumably due to consistent pumping. Well 95M001 (Figure 31) returned levels around 6460 ft elevation during 1999, which is appreciably lower than the historical level of 6510 ft. Field measuretnen[s are presented in Tables I~ and 16 for+vells 001-83-107 and 00875-EFC. Field parameter measurements on these Trout Creek Sandstone wells monitored during 1999 returned values within anticipated ranges with no mine related impacts evident. Field measurements and water quality parameters for wells 001-83- 106, 95M001, FBR-'~-E, 97012TC, and 97013TC are provided on Table 14, and Tables 17 through 20. At well 001-83-106 (Table 14) a new minimum value was recorded for lab pH, and new maximum values were recorded for field and lab conductivity's. The historically elevated pH readings for this sight seem to have moderated slightly. At well 95M001 (Table 17) a new minimum value for dissolved iron was recorded, and ne+a maximum values for lab pH, carbonate, dissolved molybdenum, and ortho-diss phosphate +azre recorded. The 1999 pH readings continue to be relatively Itiglt at this site. At +vell FBR-.'.-E (Table 18) a new maximum value for bicarbonate +vas recorded. Higlt pH readings appear typical for this well also. Fish Creek Sandstone: During 1999, nvo Fish Creek Sandstone wells (91M001 and 91M004) required monitoring for water levels on a quarterly basis. Monitoring requirements were met during the 1999 Water Year at these wells. An additional well (Ashley) required semi-annual monitoring for water levels and field parameters, and annual water qualiq~ sampling. We wire unable [o obtains an adequate water quality sample from this well due to temporary subsidence related dewatzring. A sample has been obtained recently and will be • reported in the 2000 AHR. Tables 21, 22, and 23 provide summaries of the 1999 Water Year data collected a[ each site. Figure 40 provides graphical representation of the period of record +vater levels measured at sites -4