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,~ <br />• The North Fork of the Gunnison River should not be subsided or strained by <br />longwall mining in the nearest longwall panel (Panel 1) <br />• A possible landslide area which overlies portions of Panels 5 through 7 should <br />not be adversely impacted and, in fact, potential subsidence should enhance <br />stability of the possible landslide mass by creating a buttressing trough. <br />• Subsidence will probably progressively drain any water impounded in the <br />overlying mine workings, although it is not known whether water is actually <br />present in the old workings. <br />These conclusions do not change the subsidence considerations presently discussed or <br />illustrated in the permit document so revision of existing permit materials is not necessary. <br />The report does identify potential concerns relative to subsidence of old State Highway 133 <br />and the adjacent cut slopes due to longwall mining in Panel 1. Progressive mine <br />development in this area has identified constraints related to both the configuration of the <br />coal seam and roof conditions which effectively preclude longwall mining in the eastern end <br />of this panel. Any coal extraction in this azea will involve conventional room and pillar <br />operations, effectively precluding the potential longwall-related subsidence effects identified <br />in the report. Oxbow is also proceeding with installation of an additional subsidence survey <br />monument at the location of water monitoring Station WSC-22. This point will be <br />incorporated into Oxbow's subsidence monitoring program as soon as longwall mining <br />operations progress into the adjacent panels. <br />We appreciate your continuing cooperation and consideration and trust that this submittal <br />will effectively address the requirement of Stipulation 28. Please feel free to contact Tom <br />Anderson at (9970) 959-5122 or myself at (970) 879-6260 with any questions regazding this <br />submittal or related matters. <br />Best regards, <br />Watson for Oxbow Carbon & Minerals, Inc. <br />/~~i~i/~~~~4zGZL~IOia <br />Jerry .°°ettleton <br />Senior rolect Manager <br />JMN::ypl <br />cc: T. Anderson/Oxbow <br />