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1 ' Memorandum to Christine Johnston October 7, 1999 Page 9 ' Location 9. Located at monitoring wells SOM-45-H-1 and SOM-45-H-2 above projected longwall Panel 13A where no mining has yet been done. • Overburden depth to the B-Seam is about 850 ft. 1 • No cracks were observed in our traverse from previous site (Location ]0 of September 1998) to this location. ' Water level measurements were normal on 7-20-99. Location 10. Located above the mined-out area of longwall Panel 12 at the southern end of a 2,000-ft, semi-circular traverse in the upper part of the Horse Gulch drainage. • Overburden thickness to B-Seam ranges from 1,000 to 1,250 ft. ' • Traverse was done to see if any subsidence features were present in this azea where soil and colluvium is relatively free of brush, and features could be readily detected. ' • No cracks or depressions were observed throughout the length of the traverse. ' Location 11. Located at the largest sandstone outcropping of sandstone (Apache Rocks) in the Apache Rocks Permit Area. ' • Overburden depth to B-Seam is about 1,300 ft. • No cracks are present in this expanse of rock at present. The longwall face in Panel 12 is 400 ft west of point as of 9-16-99. • This site should show subsidence features when the face moves within the area of influence ofthis location. Location 12. Located north of Minnesota Reservoir and about 400 ft west of the confluence of ' the Horse Gulch drainage with the reservoir. • Landslide-related cracks, which Ron has observed over the last 2 years, trend N55°W, and are as much as 1 % ft wide and 1'/~ ft deep. • The cracks appear to be part of a landslide caused by water seepage 200 to 300 ft above this location. Movement seems to be southeastward toward the confluence of Horse Gulch and Minnesota Reservov. 1 Wright Water Engineers, Inc., 2490 W. 26'" Avenue, Sle. 100A, Demer, CO 80211 Tel. 303J480.1700; Fax. 303/460.1020, e-mail:krwright@vrtighhvater.com