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• working districts were eventually sealed. Drill hole LW9-3 was drilled to monitor mine gases and assess the fire condition. Venthole LW10-1 through LW10-7 were drilled in 1997. Venthole LW11-1 to LW11-4 were drilled in 1997. Ventholes LW11-6, LW12-1, LW12-3, and LW12-5 were drilled in 1998. When necessary, air pumps are installed at the wellhead to improve mine ventilation. Degasification holes are utilized as necessary to degas the underground workings. The vent holes located within Longwall Panels #1 through #12 are shown on Map 1, Surface Facilities Map and/or Map 147, Small Area Exemptions Location Map. Access to the locations are along existing roads and from there to hole locations by cross country at-grade access with minimal blade work only where necessary. Red Wash crossing by heavy equipment during drilling will be across solid rock base, or gravel base if a solid rock base is not present. 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. The access route constructed was waterbarred to prevent erosion until abandonment. 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 removing about one foot of 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 disturbance during drilling. Sediment control of the drill pad areas is achieved by various methods described in Illustration 44. See Illustration 44 "Typical Borehole, Exploration, and Shaft Pads", "Drill Sites -Gentle Slopes", and "Drill Sites with Good Cover'. During the grazing period from December 1 through May 15, the mud pits will be left in a reasonably dry condition so they do not pose a hazard to sheep. Upon successful drilling and hole completion, the overburden from the mud pits is backfilled and smoothed out. The disturbed area (drill site and mud pits) is ripped to a minimum depth of one foot below grade prior to topsoil replacement. Stockpiled topsoil is spread evenly back over the • Minor Revision 121 (5/2001) III-28