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Memorandum to Henry Barbe <br />September 27, 2000 <br />Page 10 <br /> • No subsidence cracks or other features were observed on traverse from Location 7 to <br /> Location 13 across colluvium and soil consisting of primarily silty and sandy clay. <br /> • Crenulate cracks are observed on road and in a clearing near points: (1) Crenulate crack <br /> in clearing, as much as %: inch wide, and about 12 feet long trends E-W to NSOW; (2) <br /> Straighter crack in drill road (up to 3/8 inch wide) trends N-S. <br /> • Note 1: Both crack trends are roughly parallel to the longwall panel boundary and face. <br />I • Note 2: On September 9, 1998, when no extraction mining had been done, Crenulate and <br /> crow-foot type cracks that generally trended E-W and N-S were also observed at this <br /> location. At this time the cracks were wider and more extensive than now, when <br /> extraction mining had been done. in 1998, the cracks were 1 to 2 inches wide and <br /> extended along the road about 125 feet (see WWE report to MCC dated November 19, <br /> 1998, for more details). <br /> Location 14. Located at Drill Hole SW-1 and also Location 11 of September 9, 1998. <br />' • Made two ATV traverses: (1) along drill road across the heads of Pond and Slide <br /> Gulches and (2) along drill road to Horse Gulch to arrive at this point. Traverse (1) was <br /> located above the western end of longwall panel 13, and extended to its westem limit. <br /> • Projected overburden thickness to the B-seam of Traverse (1) ranges from about 1,000 to <br />' 1,200 feet. <br /> • No cracks or other subsidence features were observed on Traverse (I ). Traverse (2) to <br />' Location 14 is located 1,000 to 1,300 feet west of the westem boundary of panel 13A (the <br /> current position of the longwall face is beneath Horse Gulch). <br />' Location 15. Located in silty clay soil and alluvium at Horse Gulch at twin water <br />monitoring wells SOM 45-H-1, and SOM 45-H-2. The wells are positioned 20 <br />feet apart in a north-south direction. <br />• No cracks or other features resembling subsidence were observed during ATV traverse <br />along drill road from Location 14 to Location 15. The traverse was west, then south of <br />longwall panel 13A. <br />• A 500-foot pace-traverse northward up Horse Gulch, which is located above the current <br />longwall face of panel 13A, revealed no cracks in the soil and alluvium. <br />• A few small cracks were observed in the dam of a small, dry pond located 400 feet north <br />of Location 15 on the return traverse from point I SA. Projected overburden thickness to <br />the B-seam is about 600 feet. The cracks-which are as much as %: inch wide, an <br />estimated 1.5 feet deep, and up to 10 feet long~onverge and diverge in an irregular <br />Wright Water Engineers, Inc., 2490 W. 26'" Avenue, Ste. 100A, Denver, CO 80211 <br />Tel. 303/480-1700; Fax. 303/480-1020, e-mail:knvright@wrightwater.com <br />