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J.E. Stover & Associates -12- Bowie No. 2 Mine May 31, 1996 the hazards on this specific site, as recommended by Mr. Junge. Appropriate geotechnical reconnaissance should be completed, including visual inspection, mapping and aerial photographic examination. This should be followed by detailed investigations through test pits and/or angering. Appropriate samples should be collected for field and laboratory determination of material strengths. After the specific type and location of geologic hazards have been defined, the geotechnical engineers and engineering geologists can identify the design parameters of concern. Appropriate material strengths and failure plain orientations can then be utilized to complete foundational analyses and stability analyses for the proposed facilities. Finally, similar analyses should be performed to demonstrate the long term structural and geomorphic stability of proposed reclaimed configurations for these surface facilities. Reports of all of these activities must be reviewed and approved by the Division and incorporated into the permit application by BRL. Cuts and fills on landslide materials, such as those proposed to accommodate the surface facilities at the Bowie No. 2 mine, can be particularly problematic. The removal of lateral resistance and the placement of surcharge loads can rejuvenate long-dormant landslide movement. Significant surcharges will result from the placement of buildings, conveyors, road surfacing, coal and rock stockpiles, coal silos and sediment ponds. Topographic modification and the construction of drainage conveyances can introduce water into landslide materials resulting in the rejuvenation of movement. Vibration from conveyors, trucks, coal breakers, rock crushers, ventilation fans, and blasting can impose dynamic loads on cuts and embankments, resulting in landslide rejuvenation. Because of the unique peak strength versus ultimate strength relationships commonly characteristic of landslide-prone materials, once initiated, movement is extremely difficult to stop. The Bowie No. 1 mine (previously the Orchard Valley mine) occupies areas with similar geologic hazard designations. Similar facilities proposed, approved and constructed at the Bowie No. 1 were the subject of detailed investigations and comprehensive engineering designs to mitigate the potential hazards. BRL should revisit the permit documentation of the Bowie No. 1 mine as an example of the type of site investigation and specific facility design documentation that the Division will require to demonstrate the adequacy of the proposed location and construction of the Bowie No. 2 mine surface facilities. If other examples are preferred, similar site investigations and facility engineering can be examined within the permit documents