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Memorandum to Christine Johnston <br />October 7, 1999 <br />Page 7 <br />• The model for downwarping and flexure of differing rock types presented in Exhibit 60 of <br />the West Elk Mine Permit indicates that a zone of compression would occur below this <br />10-foot depth. <br />• The cracks trend N-S with only a 5 <br />degree variation, are as much as 1'/= <br />inches wide, and are locally offset <br />vertically by as much as '/< inch (Figure <br />5). Cracks cutting the sandstone aze <br />locally offset horizontally along planes of <br />weakness, but then maintain the N-S <br />trend. <br />• The cracks range in spacing from 5 ft to <br />50 ft neaz location and from 50 to 150 ft <br />either way from point along ridge. <br />• Two compression <br />inches high 4 ft <br />observed next to <br />cracks (Figure 6). <br />bulges, as much as 6 <br />long and wide, were <br />two different tension <br />Location 7. Located at monitoring well SOM-16-H (F-Seam Well). <br />• Overburden depth to B-Seam is about 1,400 ft. <br />• Ron Hanna reports that the monitoring probe was obstructed at 840 ft during his visit on <br />7-20-99. The casing is apparently offset or kinked at this depth now. Before this, he was <br />able to record a water level at 1,000 ft depth, a level that remained relatively constant over <br />the last ten yeazs. <br />t Wright Water Engineers, Inc., 2490 W. 26'" Avenue, Ste. 100A, Deng, CO 80211 <br />Tel. 303/480.1700; Fax 303/480.1020, e-mail:krwright@wrighMater.can <br />