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Permit C-81-071 1995 Annual Hydrology Report Four wells in the Wadge Overburden (which includes the Wadge Coal) are monitored. The wells are in the vicinity of Mines No.1 and Eckman Park. In 1995 wells 026-79-4 and 026-79-6 were replaced by 026-M94-001 and 026-M94-002. Water Levels Water levels in the toe of the Mine No. I Wadge Overburden wells have been measured since 1979 (Figure 4). Water levels have been measured in the two new wells since 1994 (Figures 5 and 6). The water levels generally dropped when strip mining occurs nearby, but recovered when the area is backfilled. The data indicates that the water levels in the Wadge overburden vary a small amount seasonally, with levels typically rising following spring snowmelt and recharge and then declining through the summer, fall and winter. Water Quality The water quality data for the Mine No. 1 Wadge Overburden wells are summarized on Tables 4 through 9. A plot of dissolved solids is presented on Figure 7. The baseline water quality of the Wadge overburden is a mixed type water with a dissolved solids level ranging from 500 mg/I to 3500 mg/L. Elevated dissolved solids levels in well s009-74-4, 026-79-4 and 006-82- 74C appears to coincide with water level recovery following backfilling and reclamation, indicating that they are affected by seepage from the spoils aquifer. Wells showing elevated dissolved solids 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 spoils water which are characterized by elevated dissolved solids, sulfate, calcium and magnesium as discussed below. Well 009-79-4 had increased dissolved solids in 1995 indicating possible impact from spoils water. The data does not indicate any significant changes in the trace metals concentrations. ALLUVIUM Alluvial sediments are monitored in the Foidel creek valley upstream and downstream of Mines 1 and in the Fish Creek valley upstream and downstream of Mine 2. Four wells completed in the Foidel Creek alluvium are monitored. Three wells completed in the Fish Creek alluvium are monitored. Water levels The plots of the historic water levels in the four Foidel Creek alluvial wells are presented on Figures 8 and 10. The plots of the historic water levels in the Fish Creek wells are presented on Figures 11 through 13. The water levels in the adjacent streams show the typical seasonal pattern of relatively rapid increase and decline due to spring runoff. In addition they show the general decline in water levels due to the relatively low runoff since 1987. The water levels in well 009-S-10 returned to previous levels from the higher levels in 1994. While the seasonal variation in the water levels in the Foidel Creek alluvium is readily apparenf, no impact from the mining is evident. The average water level in the 001-S-5, AV-1 and 008- EPSTEXT.DOC 03/14/96 Page 2