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• calendar year, monitoring was commenced on two additional Foidel Creek alluvium wells (FO-I and FO-4) and two additional Middle Creek alluvium wells (AVM-1 and AVM-2). Fidel Creek Alluvial Groundwater: During 1998, five Foidel Creek alluvial wells (009-S-1Q 001-5-5, 008-AV- 2, FO-I, and FO-4) required monitoring for water levels and field parameters on a monthly basis, and water quality sampling on a quarterly basis. An additional well (008-A V-1) required only monthly monitoring for water levels and field parameters. All monitoring requirements were met at these sites. Tables 20 through 25 provide summaries of the 1998 Water Year data collected at each site. Tables 20a through 25a provide period of record statistical summaries of collected data at each site. Figures 35 through 47 provide graphical representations of water levels and selected water quality parameters recorded a[ each site. Water levels during 1998 remained generally consistent with established ranges and patterns and showed the typical seasonal variability of elevated water levels in the spring. Well 009-5-10 provides data far the alluvial aquifer upgradient from the mine portals. Well 001-5-5 is located just downgradient form the mine portals and surface facilities location and is monitored in conjunction with surface water monitoring site 8. Figure 39 is indicative of the general relationship between the alluvial groundwater elevations and surface water elevations at these two sites. Wells 008-AV-1 and 008-AV-2 are monitored in conjunction with surface water site 304 at a point on Foidel Creek approximately 1000 feet upstream of the confluence of Foidel and Middle Creeks. Water levels in these wells and the stream show the typical seasonal interrelationship of relatively rapid increases and • declines associated with spring runoff (Figure 40). The longer-term trends in water levels a[ these sites generally parallel the fluctuations observed in annual stream flows. Wells FO-1 and FO-4 are situated on Foidel Creek approximately overlying the gateroads between [he second and third panels [o be mined in the EMD. Typical seasonal fluctuations in water levels are depicted at these sites on figures 44 and 46. Field conductivity measurements in general at well 001-5-5 (1998 average approximately 2000) were again noted to be higher than [he upgradien[ site 009-5-10 (1998 average approximately 1300). Moving downgradient, field conductivities at wells FO-4 and FO-I averaged 2800 and 3100 respectively based on the 1998 data. Further downgradient, field conductivities at well 008-AV-2 are averaging approximately 1620. Conductivity values a[ well 009-5-10 fluctuated within previously established ranges during 1998. The generally increasing field conductivity trend noted in previous years for well 001-5-5 appears to be leveling off in the 1998 data. Field conductivity measurements at wells 008-AV-I and 008-AV-2 are comparable to measurements at well 001-5-5 and occurred within previously established ranges for these sites. As indicated on Figure 43, TDS concentrations at well 008-AV-2 continued to be stable during 1997. TCC will continue to monitor the direction of this trend. Atwell 009-5-10 (Table 20), new minimum value was documented in August 1998 for lab pH. At well 008-AV- 2 (Table 22),a new minimum value was recorded for lab pH August. Well FO-I (Table 24) and FO-4 (Table 25) established many new maximum and minimum values for tested parameters due to the limited period for which • values have been collected at these sites. FO-I and FO-4 exhibit field conductivities notably higher than alluvial -6-