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Christine Johnston, MCC <br />November l9, 1998 <br />Page 4 <br />within the angle of draw of Panel 10). This location is in the vicinity of the recently <br />constructed Sylvester Gulch Facilities Area and cracking may be due to construction settling. <br />Cracks: <br />• Trend N 1 ~°W, as much as 3 inches wide; estimated cause mass-gravity movement = 90% <br />and subsidence = 10%, with construction of the road causing the mass-gravity movement. <br />Location 7. Located about 1,400 feet south of Location 4, about 500 feet west, and about 150 <br />feet above, old Sylvester Gulch road; designated spring 2l-I, flow estimate by Ron Hanna of <br />4 gpm; spring issues from base of sandstone outcrop about 200 feet east of the east boundary <br />of longwall Panel 10. <br />• Mining influenced spring azea (from subsidence development curves in Exhibit 60) from <br />about December 1997 through January 1998. <br />• The spring was first observed by Ron Hanna on May 19, 1997. <br />Location 7-A. G-l6 Located at the point (toe) of anorth-trending ridge where the strata dip <br />northward at about 5 degrees. According to Ron Hanna, points of ridges in this area are a <br />common location for springs, and this is no exception. <br />• More springs became visible during the construction in the area of the shaft #3. <br />G-16a. Located about 200 feet south of G-l6; a new spring suddenly burst out (punched <br />out according to Ron Hanna) and first measured on May 31, 1996. <br />• There was no construction at the time. <br />• This now is the source of the majority of flow in the G-16 area. <br />• Mining in longwall Panel (0 should not affect this spring because it is located outside its <br />azea of influence (angle of draw would need to be about 55 degrees from the vertical to <br />influence the spring azea). <br />Location 8. Located on a 4-wheeler trail about 1,000 feet south, southwest of the southeast <br />comer of Panel 10 roughly above the B-East Mains. Cracks: <br />• Trend N20°E to diverging, crowfoot, crenulate pattem, up to'/< inch and locally 1 inches <br />wide and 8 to 9 inches deep, ZS to 30 feet long. <br />• ~0 feet north of this location are diverging, crows-foot pattem cracks'/. to'/. inches wide <br />grading into cracks trending N20°E and E-W '/. to'/. inches wide. <br />Location 9. Located 400 to 500 feet southwest of SOM-2-H above development mining only. <br />Cracks: <br />• crenulate. crow-foot diverging cracks that generally trend E-W and N-S and are 1 to Z <br />inches wide and 7 to 8 inches deep. Cracks, which extend about 125 feet along the road <br />and have vertical sidewalls, look very recent (only a few weeks old). <br />Wright Water Engineers, Inc., 2490 W. 26'"Avenue, Ste. f00A, Denver, CO 80271 <br />Tel. 303/480-1700: Fax. 303/480.7020, e-mail:krwright@wrightwater.com <br />