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Tables 4 through 7 provide summaries of the 2000 Water Year data collected at each site. Tables 4a through 7a provide period of record statistical summaries of collected data a[ each site. Tables 4b through 76 provide period of record water level summaries for each site. Figures 4 through 1 I provide graphical representations of water levels TDS concentrations recorded at each site. The potentiometric surface in itte Wadge Overburden is generally observed to slope from south to north in monitored wells in the vicinity of Mine I and Eckman Park as shown by water levels in wells 009-79-4, 006- 82-74C, 94M001, and 94M002. During 2000, water levels in well 006-82-74C (Figure 4) re[umed to levels typical prior to the 1998 Water Year. Well 009-79-4 (Figure 6) retumed water level values comparable to those of recent years. Well 94M001 (Figure 8) continued on the decline which began in 1996. And well 94M002 (Figure 10) returned sable water levels. The water quality data for the Mine No. 1 Wadge Overburden wells are summarized on Tables 4 through 7. Plots of TDS concentrations are presented on Figures 5, 7, 9, and l 1. The baseline water quality of the Wadge overburden is a mixed type water with a TDS level ranging from 500 mg/1 to 3500 mg/L. Elevated TDS levels in wells 006-82-74C and 009-79-4 appears to correlate somewhat with seasonal recharges from the spoil aquifer following backfilling and reclamation, indicating that they are affected by seepage from [he spoils aquifer. Wells showing elevated TDS tend to also have elevated sulfate, calcium and magnesium and reduced SAR compared with undisturbed Wadge Overburden groundwater chemistry. This is consistent with mixing with spoil waters which are typically characterized by elevated TDS, sulfate, calcium and magnesium as discussed below. In 2000, the TDS at well 006-82-74C returned to the higher levels typical prior to the 1997 Water Year. In 2000, the TDS at well 009-79-4 continue to be more typical of the normal levels recorded prior to [he higher levels recorded in 1995. TDS levels in wells 94M001 and 94M002 are noted [o be significantly lower than those recorded in wells 006-82-74C and 009-79-4. The data does not indicate any significant changes in the trace metals concentrations. • No anomalous water quality impacts attributable to mining were evident in data collected from Wadge Overburden wells during 2000. Water quality parameters for these sites are typically within previously established ranges with a few exceptions. At well 006-82-74C (Table 4), new maximum values were recorded for field conductivity, total dissolved solids, dissolved sodium, and nitrite. At well 009-79-4 (Table 5), new minimum values were recorded for lab conductivity, lab pH, and dissolved manganese. At well 94M001 (Table 6), new minimum values were recorded for dissolved magnesium and dissolved iron. ALLUVIUM Alluvial sediments are monitored in the Foidel Creek valley upstream and downstream of Mine 1 and Eckman Park and in the Fish Creek valley upstream and downstream of Phase 111 bond released Mine 2. Three wells completed in the Foidel Creek alluvium are monitored (001-5-5, 009-5-10, and 008-AV-2). Three wells completed in the Fish Creek alluvium are also monitored (006-AY-l, 006-AZ-3, and 006-A W-2). Foidel Creek Alluvial Groundwater: During 2000, three Foidel Creek alluvial wells (009-5-10, 001-5-5, and 008-AV-2) required monitoring far water levels and Held parameters on a monthly basis, and water quality sampling on a quarterly basis. All monitoring requirements were met a[ these sites. Tables 8 through 10 provide summaries of the 2000 Water Year data collected at each site. Tables 8a through l0a provide period of record statistical summaries of collected data a[ each site. Figures 12 through 17 provide graphical representations of water levels and TDS concentrations recorded at each site. Water levels during 2000 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 for the alluvial aquifer downgradient from the Eckman Park mine (Figure 14). This well, like most others monitored, exhibited lower levels in the spring and therefore through out the water year than have been observed for a period of several years . Well 001-S-5 is located downgradient from Mine 1 and below the Twentymile Coal • Company mine portals and is monitored in conjunction with surface water monitoring site 8. Figure 12 is indicative of the general relationship between the alluvial groundwater elevations and surface water elevations CYCC2000.doc 1/31/01 2