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GROUND WATER MONITORING Bedrock Two monitored wells (008-77-58 and 008 79-G; see Figure 2) are completed in the Wadge Overburden (which includes the Wadge Coal). Water Levels -Levels in the wells have been measured since 1979 (Figures 4 and 5). Water levels in Well 008-77-58 showed a sharp decline from March 1979 to February 1980. A generally increasing trend has been noted since, with recorded water levels approaching the initial levels documented a[ this site. An wwsually large fluctuation was noted for 1998. Water levels in Well 008-79-G rose abnrptly in 1980 and continued to show an increasing trend during the period 1981 Hmrough mid-1986, followed by a slight decreasing trend during the period 1987 through 1993. Water levels since 1993 have shown to be generally increasing. The abrupt rise in 1980 is probably due [o water level recovery in the Wadge Coal and overburden following cessation of mining in the vicinity of this well in 1979 or 1980. The trends from 1983 on appear to follow the general climatic trends illustrated by the flow data presented as Figures IS and I7. The data illustrated in Figures 4 and 5 generally indicates Heat Hme water level in time Wadge overburden varies seasonally. Recorded water levels N the spring are typically higher than in the fall. Seasonal fluctuations in both wells typically vary by as much as G feet AlHmough the seasona! fluctuation in Well 008-79-G appeared to have diminished somewhat in the time period following 1986. The 1997 • ^uctuation in well 008-79-6 was somewhat greater than that recent trend, but Hie similar pattern seen in Hme nearby alluvial well 008-AV-2 continues to demonstrate a relationship to [he trends and fluctuations of Foidel Creek and tlme alluvium. Water level fluctuations observed during 1998 were consistent with previously established patterns at both wells. Ecplanations for Hie water level Fluctuations and Vends in Well 0118-77-58 are not readily appazent. The water levels dropped abruptly behveen 1979 and 1980. Tlme reason for Hie decline may be related [o dewatering operations occurring during Hie aborted wmderground mining attempt at Mine No. 3 (May 79 to Jwme 1980). Water level recoveries, however, are not nearly as abrupt although a relatively steady upward trend is evident. Within this long term pattern, the water level fluctuations at this well generally follow Hme longer term climatic trend, with slight increases noted for the wetter period 1982 through 1986 followed by a slight decrease for the dryer period 1987 through 1992. Water levels from 1992 tlwuglm 1998 are again noted as generally increasing, though 1998 displayed a greater than usual fluctuation similar that experienced in 1990. The associated climatic patterns are again reflected in the flow data presented as Figtmres 15 and 17. A relatively dry year occurred in 1993 but a corresponding decrease in water level is not reflected in the water level data recorded for Well 0(18-77-58. A declining response is noted in time water level data for 1993 at Wcll 008-79-G. The t}yical seasonal fluctuation expected, with higher water levels in the spring and relatively lower levels in tlme fall, is apparent in both wells 008-77-58 and 008-79-G. Tables 6B and 7B provide period of record statistical summary information for water levels at Wells (108-77-58 and 008-79-G. Water Quality -Water qualiq• data for the Wadge Overburden wells at Mine 3 is presented on Tables 6, GA, 7, and 7A. Plots of period of record total dissolved solids (TDS) data for both wells are presented as Figures G and 7. Water quality constituent concentrations for most of the parameters • measured during 1998 were within the established ranges historically associated with each site. However, in September ,anew nummum value was recorded for pH (lab). 2