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West Elk Mine Approximately seven months following the B Seam mining beneath SOM 38-H-1, the casing of the well was appazently blocked or distorted, thus prohibiting additional water level monitoring. The 1993 Annual Hydrology Report attributes the loss of this well to subsidence. However, B Seam longwall mining was occurring at that time in panel 2NW more than 800 feet away from well SOM 38-H-1 on the opposite side of 200 foot wide chain pillazs dividing the 1NW panel from the 2NW Panel. Following complete mining of the 2NW Panel, no further blockage was observed and a water level was measured in Mazch 1995. Further monitoring of this well was then continued. Monitoring well SOM C-72-H is located above the chain pillars between panels SNW and 6NW. This well is completed immediately above the B Seam and is well within the expected subsidence cave zone. As expected, while advancing the SNW longwall panel, the casing was appazently split and offset sufficiently to disallow continued water level measurements. Figure 25 shows the reaction of the water level in the well as it was approached (December 1994) and finally lost (January 1995) to the longwall mining operation. The water contained within the monitored water- bearing unit immediately above the B Seam was probably lost to the mine workings. However, did not observe an increased seepage or inflow in the area of SOM C-72-H as the longwall face was advanced through the area. In February 1995, water level probes were once again able to reach the bottom of monitoring well SOM C-72-H. At that time, sufficient recompression of the azea azound the well due to adjacent azea subsidence had occurred to allow for water level observation equipment. As . expected, no groundwater was observed at that time. Monitoring wells SW-1 through SW-6 aze all located along the eastern edge of the 1NW longwall panel. Each of these wells is approximately 60 feet deep and completed in the Barren Member of the Mesaverde Formation. Due to the deep overburden cover, these wells would not be expected to show effects resulting from fractures extending up from the mine. However, they aze valuable for detecting effects of surface cracks on shallow groundwater. Figure 26 and Figure 27 shows the observed water levels in the wells since initial observations in 1988. Each of these wells shows consistent water levels at or slightly above the bottom of the well even as the 1NW longwall panel face advanced beneath them. This observation is significant because there is a documented surface or tension crack of approximately 100 linear feet in length between monitoring wells SW-5 and SW-6 which developed sometime prior to its first observation in August 1993. Despite this crack, water levels in SW-5 and SW-6 have remained constant. These observations indicate that surface cracking, to the degree that it exists in the area, does not extend into the water-bearing zones into which wells SW-5 and SW-6 aze completed (approximately 40 to 60 feet below the ground surface). This is consistent with Mr. Dunrud's assessment of surface cracking, as discussed earlier in Section 2.05.6 and Exhibit 60. MCC encountered poor roof conditions and initial colluvial inflows of 50 gpm while mining the bleeder entries at the north ends of panels 6NW and 7NW. These inflows diminished to nearly zero over a few weeks. These locations aze beneath Lone Pine Gulch and have an overburden thickness of 300 to 400 feet. 1.05-116 RevisedNovembes 1004 PRIG