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10-5/8 inch holes (LW2-1 to LW2-8, LW2-4B and LW2-6B) were drilled in the longwall #2 and
<br />eleven holes (LW3-1 to LW3-11) were drilled in the longwall #3. Disturbance of the archaeological
<br />site 5RB859 was mitigated. Hole LW3-12 and holes LW4-1 to LW4-13 were drilled in 1990.
<br />Holes LW4-14 to LW4-17 and LW5-1 to LW5-17 were drilled in 1991. Holes LW5-8 to LW5-15
<br />and LW6-1 to LW6-3 were drilled during 1992. Vent holes LW6-4 to LW6-12 and LW7-3 to LW7-5
<br />were drilled during 1993. Holes LW7-6, LW7-8, LW7-10, LW8-2, LW8-3 and LW8-5 were drilled in
<br />1994. LW7-1 and LW7-2 were permitted but not drilled because of the change in the start line
<br />location for LW -7. Holes LW7-7, LW7-9, LW8-1, LW8-4 and LW8-6 were permitted but not drilled.
<br />On January 31, 1996, the mine caught fire near LW -9 face. Emergency holes LW9-1 and LW9-2
<br />were drilled to inject CO2. The working districts were sealed. Hole LW9-3 was drilled to monitor
<br />mine gases and assess fire conditions. Vent hole LW10-1 thru 7 were drilled in 1997, LW11-1
<br />thru 4 in 1997, LW11-6, LW12-1, 3, and 5 in 1998, LW67-1 thru 4 in 2005, LW139-2 and 3 in 2007,
<br />LWB10-1 thru 4 in 2008, LWB11-1 thru 4 in 2009, LWB12-1A thru 5 in 2011, LWB13-1 thru 5 in
<br />2013, LWB14-1 thru 5 in 2015, and LWB15-1 thru 5 in 2018. Degasification holes are utilized as
<br />necessary to ventilate longwall gob gasses from active panels and mining districts.
<br />Spontaneous combustion forced extensive drilling to locate and control the resulting fire in 2007.
<br />Nineteen drill holes on 18 drill pads were constructed to address this issue (SC-xxxx holes). A
<br />containerized nitrogen unit with buildings and compressors were installed at RDH -3 (see Map 155)
<br />with a 2 and 3" surface pipeline strung to various drill holes. A second nitrogen plant was installed
<br />south of Slot Storage in 2014 (Map 159). Nitrogen is injected to help inert the mined out areas.
<br />MSHA requires nitrogen injection/monitoring holes for current longwall panels. N7-53; N8-12, 21,
<br />36, 51, 55; N9-12, 26, 38, 57, 62; N 10-12, 26, 38, 53, 62; N 11-15, 28, 43, 58, 71; N 12-12, 26, 38,
<br />53, 60; N13-11, 21, 33, 47, and 59 were drilled to the 7th thru 13th Left entries. 43,000 feet of 2, 3
<br />or 4" plastic surface pipeline carries nitrogen to these holes.
<br />Drill locations are shown on Map 147. Access to the locations are along existing roads where
<br />feasible. New light use roads are constructed where necessary.
<br />The two -track access to LW2-1 from LW2-2 is about 1/2 -mile long. Part of the track is constructed
<br />around the side of a hill necessitating approximately 60 feet of the track to have a cut ranging up
<br />to 6 feet deep. The track width is maintained around 12 feet. The only disturbance of any
<br />significance was for the cut to be made on the side of the hill. Some rock blasting was required.
<br />An 18 -inch culvert was installed on the access road to well LW2-1.
<br />The drill sites are about 100' x 100'. A site is formed by first salvaging available topsoil. The
<br />topsoil is stockpiled at one end of the drill site. Additional earthwork is minimized since the drill
<br />Minor Revision #171 (06/2017) III -27
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