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Subsidence Field Observations <br />West Elk Mine <br />July 22-24, 2003 <br />4.0 OBSERVATIONS AND EVALUATIONS ALONG FIELD TRAVERSES, AND AT <br />INDIVIDUAL LOCATIONS DURING JULY 22 THROUGH JULY 24 <br />4.1 Subsidence Observations and Evaluations on July 22, 2003 <br />4.1.1 Traverse A-A' <br />Traverse A-A' begins at sharp bend in road about 3,000 feet north and east of the locked gate, <br />thence to the fork in road to West Flatiron and road [o Drill Holes 96-27-1 and SOM-123 (Map 1 <br />and video for details). <br />• Traversed above the eastern portions of longwall Panels 13 and 13A, the un-mined, western <br />part of the un-mined part of longwall Panel 17, mined longwall Panels 15 and 16, and the <br />southern, middle part of longwall Panel 14. <br />• Bedrock (sandstones, siltstones, and mudstones of the Barren Member of the Mesaverde <br />Formation), weathered bedrock, and surficial material (colluvium and soil) were encountered <br />during the traverse. <br />• Overburden depth to the B-Seam ranges from 1,000 to 1,100 feet. <br />• No subsidence features (cracks, bulges) were observed. <br />• A slump feature was observed in the cut bank located about 4,500 feet east of Point A. <br />However, this feature is not related to mining because only development mining has been <br />done in the area. <br />4.1.2 Traverse B-B' <br />Traverse B-B' begins at Point A' and ends at fork in drill roads-one that goes to the top of West <br />Flatiron and the other to Drill Hole RAV-10. <br />831-032.610 Wright Water Engineers, Inc. Page 7 <br />September 2003 <br />