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West Elk Mine <br />2.04-35 Rev. 11/04- PR10, 04/06- PR10, 09/07- PR12, 10/08- PR14; 01/22- MR459 <br />Recent published and unpublished reports by H. Maleki and W. Koontz (1997), J. Corbett <br />(1997), A. Mayo (1998, 2000, 2004), R. Harris (1998), and S. Herron (1998) provide insight into <br />the character, distribution, and water bearing capacity of the major tectonic fault systems. <br /> <br />Quotes and a brief discussion from some of the papers follow: <br /> <br />H. Maleki and W. Koontz (1997) studied the joints and cleats as observed in the B Seam mine <br />works and concluded “The predominate jointing of the sedimentary rocks is N 68 E to N 74 E, <br />with secondary jointing at N 28 W and N 35 W. As mining and exploration extend farther east <br />and south, more faults are being discovered. The faults trend almost parallel to the major joint <br />direction with offsets up to 2.5m up thrown to the east.” <br /> <br />In an interpretation of the airborne magnetic survey J. Corbett (1997) summarizes “The newly- <br />defined deep intrusive anomaly, centered south and east of Somerset, is interpreted to have several <br />deeply buried cupolas, rising from a deeper larger source, that cause the two broad lobes of the <br />magnetic anomaly. Most likely the tops of the cupolas are 6,000-10,000 feet below the surface and <br />do not extend into the near surface.” <br /> <br />S. Herron and D. Bagley in the Steffen Robertson and Kirsten report (1998) analyzed the structural <br />data available and concluded “These intrusive are likely to have caused doming of the overlying <br />Rollins Sandstone and coal measures during emplacement. The small-displacement normal faults in <br />the coal measures are interpreted as expressions of this doming.” <br /> <br />Seven major fault systems that were identified from north to south are: Unnamed, Oliver No. 2, B <br />East Mains (BEM), 14HG, West Flatiron, Deep Creek, and Gunnison zones. Two of the seven <br />zones are not positively identified in the mine works but inferred from seismic and analytical <br />techniques. Two of the known five zones, BEM and 14HG, have exhibited displacement greater <br />than five feet and are strong conduits for water and methane gas inflows. The Unnamed, Oliver No. <br />2, and West Flatiron fault zones are low displacement fault and fracture zones that have limited <br />water-bearing capacity. Fault waters are described more thoroughly in Section 2.04.7 under the <br />discussion of Groundwater Quantity Characteristics. <br /> <br />E Seam mining in the South of Divide and Southern panels permit area encountered three prominent <br />fault systems. One of these was crossed in the E South Mains to the west of longwall panel LWE3, <br />and another fault system was crossed to the west of longwall panel LWE6. The third fault system <br />caused the E South Mains to be terminated and the Sunset Mains were turned to the east from that <br />point and paralleled the fault system. Provisions for safely crossing these faults included <br />modifications to pillar and crosscut layouts, additional roof support appliances, and additional floor <br />to roof standing support. <br /> <br />Weathering and Burn <br /> <br />Weathering and burning of the coal and associated strata occur on the property. Burned areas in <br />all seams are mapped from drill hole data, by direct observation of burned areas on the surface, <br />and by careful examination of color and color-infrared aerial photographs. Some burned areas