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returned levels around elevation 6520 during 1995. The southermnost Trout Creek well (001-83-107) exhibited lower water levels in the 6900 ft elevation range while the northernmost well (008-75-EFC) increased to around the 6630 ft elevation level. During 1995, with the exception of well001-83-107, water levels in the Trout Creek were observed to be consistent with recently obtained measurements. Well001-83- 107 continued to show lower water levels than those typical prior to 1992. Well 001-83-106 remains drawn down presumably due to consistent pumping. Well FCM#2 well levels were somewhat erratic during 1995 and TCC has completed anew monitor well in this location to clarify the potentiometric surface in this area. Measurements will be available from the new well in the 1996 Annual Hydrology Report. We11 006-8 3-48C exhibited a fairly steady decline prior to being undermined during 1993 and well008-75-EFC remains stable. Two measured parameters at well 001-83-106 returned values outside of previously established ranges during 1995, however, neither are believed to evidence mine related impacu. Specifically, new minimum field and lab conductivity values were recorded in September along with a new minimum total alkalinity value. Reduced pH and elevated iron and manganese levels noted at this site last year were no longer evident. Water quality sample results obtained from well FCM #2 are presented in Table 10. Characteristic Trout Creek water is indicated with the exceptions that pH and alkalinity values remain elevated though lower than last years values. This is likely related to the alkaline cement grout material utilized to complete this well. As previously noted, TCC installed a replacement well for this site and will begin monitoring new well in the spring of 1995. Field parameter measurements on monitored Trout Creek Sandstone wells during 1994 • returned values within anticipated ranges with no mine related impacts evident. Fish Creek Sandstone: During 1995, two Fish Creek Sandstone wells (91M001 and 91M004) required monitoring for water levels on a quarterly basis. Monitorin;; requirements were met during the 1995 Water r Year. Tables 50 and 51 provide summaries of the 1995 Water Year data collected at each site. Figure 92 provides graphical representation of the period of record water levels measured at these sites. Dtving the 1995 Water Year, well 91M001 showed a decline in water level between December and March which appears W correspond to mining activity in the area. Well 91M004 showed a similar decline between May and September which also correlates with mining activity in the area. Both wells showed water level increases between March and May which were likely attributable to recharge of the Fish Creek Sandstone associated with spring runoff. ALLUVIAL GROUNDWATER MOMTORING Alluvial deposits containing groundwater are monitored in the Foidel Creek, Fish Creek, and Trout Creek drainages. In the Foidel Creek drainage, sites both upsveam and downsveam of the TCC portals and support facilities are monitored. In the Fish Creek Drainage, sites upsveam and downsveam of the Mine 2 area and the Fish Creek Borehole mine dewatering facilities are monitored. During 1994 on Trout Creek, . an additional monitoring site was established downsveam of the confluence with Fish Creek. -4-