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Memo to Tony Waldron Bowie No. 2 Geotechnical Adequacy page 3 difficult:y, reminiscent of the problems encountered by Mountain Coal while facing up the F-seam portals of the Mountain Gunnison No. 1 mine. The resulting engineE~red remedial construction cost several million dollars and was margin<~Ily effective. The portals continue to evidence displacement fifteen years later, necessitating continued remedial expenditures. 2.05.3(2) Operation Description - Underground Mining The m~ijority of the following comments in this section apply uniformly to all the proposed surface facilities at the Bowie No. 2 mine. BRL included a facsimile of Raye Junge's Colorado Geological Survey Map 06), and excerpts from it's accompanying text (Exhibit 12, Volume III) in the application. Mr. Junge's map was entitled "Geologic Hazards in the Hotchkiss- Paonia Reservoir Area, Gunnison and Delta Counties, Colorado". BRL presents its proposed surface facilities on Maps 15-1 and 15-2 of the application. While comparison is complicated by the significantly differing scales of maps 06 and 15-1 & 2, it appears that the majority of the proposed BRL surface facilities lie within <~reas mapped by Mr. Junge as landslides. The vent shaft pads, the portal bench, and the coal stockpile bench appear to lie within a recent landslide zone (Ise). The conveyor, haul road and stockpiles lie within a larger and older landslide zone (IsZ). The explanation to Mr. Junge's map explains these hazard design~itions as follows. "LANDSLIDE: A landform resulting from the moderate to rapid, downward and outward movement of rock and/or soil where there is a surface or zone of weakness that separates the landslide from more stable underlying material. Landslides, including earthflows, result from the rriass movement of rock and/or soil in response to gravitational stresses and these movements may affect adjacent downslope areas. Natural and man-caused disturbance of landslide areas could initiate additional instability and mass movement. Relative age of Iz~ndslides is indicated by subscripts (1 is the youngest)." [Emphasis added]