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Memo to Tony Waldron <br />Bowie IJo. 2 Geotechnical Adequacy <br />page 6 <br />constructed at the Bowie No. 1 were the subject of detailed investigations and <br />comprehensive engineering designs to mitigate the potential hazards. BRL <br />should revisit the permit documentation of the Bowie No. 1 mine as an example <br />of the type of site investigation and specific facility design documentation that <br />the Division will require to demonstrate the adequacy of the proposed location <br />and construction of the Bowie No. 2 mine surface facilities. If other examples <br />are preferred, similar site investigations and facility engineering can be <br />examined within the permit documents for the Mount Gunnison No. 1 and Bear No. <br />3 mine:>. The history of operations of both of these same mines can provide <br />unfortunate examples of the difficulty caused by geotechnical hazards. The <br />Bear No. 3 lost its ventilation capability and had to rehabilitate its portal bench <br />and haul road due to debris flow and landslide activity. The Mount Gunnison No.1 <br />has suffered numerous expensive slope movement events impacting its portals, <br />electric substation, conveyors, refuse pile, and haul roads. <br />The following comments apply specifically to the indicated surface facilities. <br />Haul Road Along the Railroad Bed -Drainage <br />BRL proposes to build this road without a sediment control facility. Further, <br />BRL recluests a variance because a portion of these facilities lie within 100 <br />feet of the Right-of-Way for old State Highway 133. Old Highway 133 appears <br />to provide access for several of the neighboring residents as well as the Bowie <br />No. 2 mine. If Highway 133 were compromised emergency access might be <br />eliminated to the mine and the neighbors. BRL will have to provide detail <br />concerning the existing drainage conveyances along and under old Highway 133 <br />to demonstrate that changes within the mine permit area, which affect water <br />retention and routing will not overload the existing ditches and culverts and <br />compromise the old Highway. further, BRL will have to specify which <br />alternative sediment control devices and techniques will be implemented and at <br />what specific locations. <br />Haul F;oad Reclamation <br />BRL suites; "The haul road from old State Highway 133 to the portal area will <br />