2009-06-18_PERMIT FILE - C1981018A (5)

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• longwall #4 were drilled in 1990. Holes LW4-14 to LW4-17 and LW5-1 to LW5-17 were drilled in 1991. Holes LW5-8 to LW5-15 and LW6-1 to LW6-3 were drilled during 1992. Vent holes LW6-4 to LW6-12 and LW7-3 to LW7-5 were drilled during 1993. Holes LW7-6, LW7-8, LW7-10, LW8-2, LW8-3 and LW8-5 were drilled in 1994. LW7-1 and LW7-2 were permitted but not drilled because of the change in the start line location for LW-7. Holes LW7-7, LW7-9, LW8-1, LW8-4 and LW8-6 were permitted but not drilled. On January 31, 1996, the mine caught fire near LW-9 face. Emergency holes LW9-1 and LW9-2 were drilled to inject COz. The working districts were eventually sealed. Drill hole LW9-3 was drilled to monitor mine gases and assess the fire condition. Vent hole LW10-1 through LW10-7 were drilled in 1997, LW11-1 to LW11-4 in 1997, LW11-6, LW12-1, LW12-3, and LW12-5 in 1998, LWB7-1 thru LWB7-4 in 2005, LWB9-2 and LWB9-3 in 2007, and LW610-1 thru LW610-4 in 2008. Degasification holes are utilized as necessary to ventilate longwall gob gasses from active panels and mining districts. In 2007 a spontaneous combustion event forced extensive drilling to locate and control the resulting fire. Nineteen drill holes on 18 drill pads were constructed to address this issue (SC-xxxx holes). A skid mounted nitrogen generating unit with compressors was installed at RDH-3 with a 3" surface pipeline (6900') strung to SC-HG20, SC-HG26, and SC-HG33. A 575 foot 2" pipeline was stung to SC-HG11. Nitrogen is injected to help inert the mined out areas. Nitrogen injection and monitoring holes are required by MSHA for subsequent longwall panels. . N7-53, N8-51, N8-36, and N8-21 were drilled to the 7tn Left and 8th Left entries. 7,290 feet of 3" surface pipeline was placed to carry nitrogen to these holes. Drill locations are shown on Map 147. Accesses to the locations are along existing roads and by cross country access with minimal blade work only where necessary. The two-track access to LW2-1 from LW2-2, is about 1/2-mile long. Part of the track is constructed around the side of a hill necessitating approximately 60 feet of the track to have a cut ranging up to 6 feet deep. The track width is maintained around 12 feet. The only disturbance of any significance was for the cut to be made on the side of the hill. Some rock blasting was required. An 18-inch culvert was installed on the access road to well LW2-1. The drill sites are about 100' x 100'. A site is formed by first salvaging available topsoil. The topsoil is stockpiled at one end of the drill site. Additional earthwork is minimized since the drill sites are usually relatively flat. A temporary mud pit is constructed next to the drill site. All suitable topsoil material is salvaged from the mud pit areas and placed in the topsoil stockpile. The mud pits are about 20' x 10' x 6'. Any runoff water and/or water/drilling mud mixture is generally collected in the mud pit. The mud pits effectively serve as the sediment control structures for the • Minor Revision #138 (10/2008) III-27