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• Fish Creek Alluvial Groundwater: During 1999, three Fish Creek alluvial wells (006-AY-1, 006- AZ-3, and 006-AW-2) required monitoring for water levels and field parameters on a monthly basis, and water quality sampling on a quarterly basis. Tables 11 through 13 provide summaries of the 1999 Water Year data collected at each site. Tables 11a through 13a provide period of record statistical summaries of collected data at each site. Figures 18 through 23 provide graphical representations of water levels and selected water quality parameters recorded at each site. Water levels at well 006-AY-1, located on Fish Creek upstream of Mine 2, had exhibited a relatively steady increase from approximately 1990 through 1994 (see Figure 18). During 1995 and 1996, water levels were more erratic with that trend having reversed. From 1997 through 1999 levels appear more stable, with values recorded for this well more closely resembling those values recorded prior to 1990. Well 006-AZ-3 is situated downstream of 006-AY-1 and below the Fish Creek Borehole associated with mine dewatering operations for the Foidel Creek mine. Well 006-AZ-3 is monitored in conjunction with surface water site 307 and the water level relationship is presented as Figure 20. Further downstream, well 006-AW- 2 and surface water site 1002 are monitored and water levels are plotted as Figure 22. Again in 1999, the interrelationship between alluvial groundwater and surface water is evident on these two plots. No unusual water level fluctuations were noted at any of these sites during 1999. At welt 006-AW-2 new minimum values were recorded for alkalinity and bicarbonate, while a new maximum value was recorded for ammonia-free. Other monitored water quality parameters returned values at the Fish Creek alluvial wells • typically within previously established ranges during 1999. Field conductivities and TDS values are observed in general to increase in the downstream direction along Fish Creek. The highest values are noted to occur in association with well 006-AW-2. Elevated ammonia readings first detected in August of 1995 continue to be observed. SPOILS Five wells (001-SP-6, 001-SP-7, 026-SP-1, 026-SP-2, and 026-SP-3) are monitored in the spoils on a quarterly basis for water levels and field parameters. They are located at Mine 1 and Eckman Park and were installed in 1985 and 1986. Three of these wells (026-SP-1, 026- SP-2, and 026-SP-3) require semi-annual water quality sampling as well. All sampling requirements were completed at these wells during 1999. The plots of the historic water levels in the spoil wells are presented on Figures 24, 26, 28, 30, and 31. The water levels normally have a similar pattern to the alluvial wells: they respond rapidly to the spring runoff and then decline rapidly in the summer. Wells 026-SP-1 and 026- SP-3 have on occasion been dry by the fall, although this has not happened since 1988. Water levels in these wells closely mirror the pattern of the spoil spring discharges discussed elsewhere in the report. Wells 001-SP-6 and 001-SP-7 reflect fluctuation in the spoil aquifer water table attributable to pumping activities associated with the adjacent Foidel Creek Mine. Water quality data for wells 026-SP-1, 2, and 3 are summarized in Tables 14, 15, and 16 for the 1999 water year. Tables 14a through 16a provide period of record statistical summaries of collected water quality data at each site. Figures 25, 27, and 29 provide graphical representations of TDS concentrations recorded at each site. TDS values in all three of these • wells are observed to decrease during spring runoff period and increase during the latter part of the water year. cycc99 02/14/00 4