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Christine Johnston, MCC <br />November 19, 1998 <br />Page 6 <br />• Two hundred feet south, southeast of first cracks where surface is offset downward to the <br />south l0 to 12 feet across 3 to 4 cracks. <br />• Cracks have healed considerably since late June 1998 when Ron Hanna observed them. <br />CDMG-lA Location 500 to 600 feet S40°E of CDMG-I above Panel 8 (no number on map or <br />video). Cracks are 6 inches to 2 %Z feet wide and 8 inches to 2 feet deep and locally display <br />bedrock for a distance of 60 to 80 feet along the road and into the brush about l ~0 feet. <br />• Trends of cracks are N-S and N50°E; cracks extend across road and into the brush about <br />I50 feet. <br />• These cracks were not observed last yeaz. Cracks appeaz to be only a few months old and <br />are caused by landsliding, because mining beneath t}ris area was completed more than two <br />years ago. <br />CDMG-4 Located in hummocky topography above the chain pillars between longwall <br />Panels 8 and 9. Cracks: <br />• Four cracks trend north, northeastward aze nearly healed on road due to four-wheeler <br />traffic, but readily visible off road. Cracks began to arc northward to eastward north of <br />site in a typical landslide pattern. <br />• 100 to 200 feet west, southwest of the 4 cracks (still in CDMG-4 azea) are cracks much <br />wider and deeper than last year. One crack trending northwestward is up to 5 feet deep, 2 <br />%: feet wide and offset downward to the northeast about 3 feet. This crack is believed to <br />be almost totally landslide related; the longwall face had passed by this area by July 1996 <br />in Panel 8 and by March 1997 in Pane19. <br />CDMG-5 Located in typical landslide topography (bulges and depressions) above longwall <br />Panel 9. Cracks: <br />• Show local renewed movement from last year; new cracks are locally present among older <br />cracks. <br />• Trend generally east, northeast direction; cracks are 2 to 10 feet apart and are as much as 3 <br />'/: feet wide and 2 '/: feet deep. Cracks are offset downward about 10 to 12 feet to the <br />north, northwest in the northern part of the azea. <br />• Trend changes to roughly eastward on some cracks. <br />• Graben located about 50 feet southeast of previous cracks is about 25 feet wide and 5 feet <br />deep. Cracks are up to 3 to 3 '/~ feet wide in the brush on either side of the graben. <br />• Southeast of the graben are multiple cracks 1 feet to 1 '/: feet wide and deep which are <br />offset downward to the northeast as much as 1 feet; these cracks extend southeastward <br />from the graben about 50 feet. These cracks aze mostly new since last year. <br />CDMG-4A Location is 400 to 500 feet southwest of west location CDMG-4. <br />Wright Water Engineers, Inc., 2490 W. 26'" Avenue, Ste. 100A, Denver, CO 802[ 1 <br />Tel. 303/480-7700; Fax. 303/480-1020, e•mad:knvright@wnghhvater.,:am <br />