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Mountain Coa! Comparry 1997 Annual Hydrology Report West E!k A9ine r Water level observations in 96-2-2 showed an increase of more than 8 feet during WY96 and an • additional 7 feet during WY97. Conversely, 96-27-1 showed a decrease of more than 11 feet in WY96 with an additional 200 feet of decline in WY97. While the location of 96-27-] is in general proximity to the surface projection of the B East Mains Fault, it is unlikely that there is any connection because of the elevation difference and the dissimilarities in water quality (i.e., the fault water is much higher in alkalinity, bicarbonate, conductivity/TDS, chlorine, and hardness). Further observations will be closely reviewed and evaluated in an effort to determine an explanation for the decreasing water levels. Well 96-2-2 is located upgradient (i.e., south) of current mining areas. No explanation can be provided at the present time relative to the increasing water levels. Water level data obtained from monitoring well SOM-23-H-2 in WY97 show a seasonal trend representing a lazger interval than observed in WY96. Since March of 1995, water levels in this well have maintained an elevation more than 100 feet higher than observed from 1990 to 1993 and as far back as 1978. Landslide activity in the immediate vicinity of the SOM-23 well cluster, coupled with observed cascading water entering the well, suggests that the existing water level is likely the result of shallow groundwater entering a compromised casing. Because of the observed cascading water and known landslide activity at the well cluster, SOM-23-H-2 will likely be removed from the monitoring program. B-Seam Wells • There are six currently monitored wells that are completed in the B-Seam coal. These include C- 72-H, JMB-12, Rav-46, So.W-l, SOM-23-H-1 and SOM-129-H. Monitoring well C-72-H (a.k.a. SOM-C-72-H) is located in the gateroad entries between SNW and 6NW longwall panels. Observations made in WY97 show a water level that is consistent, with observations made in WY96. However, it is unclear exactly what these observed water levels aze reflecting (i.e., water contained within the B-seam or water entering the caved portion of the longwall panel from a higher elevation). This well is upgradient from the NW Panels sealed sump. Insufficient water was available in WY97 to obtain water quality samples. No water level or water quality data were obtained in WY97 for monitoring well JMB-12 in the Jumbo Mountain mining area because of the lack of water in the well. Since 1993, there has been a gradual decline in water levels to such a point that there is insufficient water in the well to obtain water quality samples. In March 1997, JMB-12 was mined through with the 9NW longwall panel and is no longer functional. MCC will request that it be removed from the monitoring program in a future application. Both monitoring well Rav-4b and So. W-] initiated water level monitoring of the B-Seam during WY96. Baseline monitoring of these two wells continued in WY97. Well Rav-4b shows a continually declining water level that started in October 1996. While the location of Rav-4b is downgradient of the surface projection of the B East Mains Fault, it is unlikely that there is any connection with the fault because of the dissimilarities in water quality (i.e., the fault water is much higher in temperature, alkalinity, bicarbonate, conductivity/TDS and hardness). Further J 8 1-03 .450 Page rig !Water ngineers