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Permit C-81-071 1996 Annual Hydrology Report • At well 009-S-10 (Table 9), new maximum SAR values were documented in both November 1995 and May 1996. A detectable concentration of nitrite was noted in May as well to establish a new maximum for this parameter. All other measured parameters at well 009-S-10 returned values within the previously established ranges throughout the monitoring year. At well 001-S-5 (Table 8), an elevated nitrate measurement was noted in November 1995. In March, new maximum values for calcium, lab conductivity, hardness, TDS, and sulfate were established along with a new minimum value for SAR. Elevated levels for lab conductivity, TDS, and sulfate persisted into May with subsequent readings returning to more typical levels. With the exception of a new maximum field conductivity reading recorded in October, 1995 at well 008- AV-2 (Table 10), all 1996 values were documented to occur within previously established ranges at this site. Fish Creek Alluvial Groundwater: During 1996, 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. Well 006-AW-2 was frozen in March - field parameters and a water quality sample were not obtained. A bent casing at this well prevented the collection of field parameter data in August and September. Repairs to the well were competed December 12, 1996 with sampling resuming on December 16. Tables 11 through 13 provide summaries of the 1996 Water Year data collected at each site. Tables 11 a 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 the recent trend having reversed. The maximum fluctuation in water level at this site over the period of record is 7.5' to date. 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 1996, 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 1996. Field parameter measurements obtained in 1996 from the Fish Creek alluvial wells remained within previously established ranges with the exception of pH measurements recorded in July at wells 006-AY-1 and 006-AZ-3. Subsequent measurements returned to typical readings. New minimum field temperature was recorded at well 006-AW-2 in February with 006-AW-2 noted as frozen in March. Field conductivities and TDS values are observed in general to increase in the downstream direction along Fish Creek. The highest levels are noted to occur in association with well 006-AW-2. Other monitored water quality parameters returned values at the Fish Creek alluvial wells typically within previously established ranges during 1996. Exceptions include a new minimum dissolved sodium concentration recorded at well 006-AY-1 in March, and new maximum nitrate and nitrate/nitrite as N values documented in May (Table 11). Well 006-AZ-3 returned new maximum calcium levels in November, March, and August, new maximum hardness levels in • November and August, new minimum SAR values in March and August, a new maximum ortho- dissolved phosphorus value in May, and new maximum total alkalinity, ammonia, lab conductivity, and nitrite values in August. Elevated ammonia readings first detected in August I \DOCUMENTWHR\ECKMAN\EP96TE%T.DOC 03/26/97 Page 4