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Memorandum to Christine Johnston <br />October 7, 1999 <br />Page 9 <br />' Location 9. Located at monitoring wells SOM-45-H-1 and SOM-45-H-2 above projected <br />longwall Panel 13A where no mining has yet been done. <br />' • Overburden depth to the B-Seam is about 850 ft. <br />' • No cracks were observed in our traverse from previous site (Location 10 of September <br />1998) to this location. <br />' Water level measurements were normal on 7-20-99. <br />Location 10. Located above the mined-out area of longwall Panel 12 at the southern end of a <br />2,000-ft, semi-circulaz traverse in the upper part of the Horse Gulch drainage. <br />• Overburden thickness to B-Seam ranges from 1,000 to 1,250 ft. <br />• Traverse was done to see if any subsidence features were present in this area where soil <br />and colluvium is relatively free of brush, and features could be readily detected. <br />• No cracks or depressions were observed throughout the length of the traverse. <br />Location 11. Located at the largest sandstone outcropping of sandstone (Apache Rocks) in the <br />Apache Rocks Permit Area. <br />• Overburden depth to B-Seam is about 1,300 ft. <br />• No cracks are present in this expanse of rock at present. The longwall face in Panel 12 is <br />' 400 ft west of point as of 9-16-99. <br />• This site should show subsidence features when the face moves within the azea of <br />influence ofthis location. <br />Location 12. Located north of Minnesota Reservoir and about 400 ft west of the confluence of <br />' the Horse Gulch drainage with the reservoir. <br />Landslide-related cracks, which Ron has observed over the last 2 years, trend N55°W, and <br />' are as much as 1 %: ft wide and 1'/~ ft deep. <br />• The cracks appear to be part of a IandsGde caused by water seepage 200 to 300 ft above <br />this location. Movement seems to be southeastward toward the confluence of Horse <br />Gulch and Minnesota Reservoir. <br />Wright Water Engineers, Inc., 2490 W. 26'" Avenue, Ste. 100A, Demer, CO 60211 <br />Tel. 303/480.1700; Fax. 303/480.1020, e-mail:krwright@wrightwater.com <br />