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J.E. Stover & Associates -23- May 31, 1996 Bowie No. 2 Mine waste pile toe is within 150 feet of the right-of-way of old State Highway 133, it might compromise the drainage facilities adjoining that highway and subject the public to an health and safety risk. In consideration of the potential risk, BRL should obtain samples of each of the three earthen material for which WESTEC assumed strength parameters and determine those properties by appropriate laboratory testing. In the case of the Mancos Shale (material "3") and the old coal mine refuse (material "4"), tests should be performed in both saturated and unsaturated conditions to determine the effect of ground water saturation. Sensitivity- style stability analyses can then be completed to determine the possible effect of unanticipated saturation of the subject materials. 2.05.4 Reclamation Plan 2.05.4(2)(c) Backfilling and Grading 71. BRL states that it will reclaim the mine facilities area, haul road and conveyor corridor by returning the borrowed material from fill slopes to cut slopes. For all the roads, benches and surface facility disturbances at this challenging site, BRL will have to propose specific reclaimed configurations. Cuts and embankments proposed to be retained as part of the reclaimed configuration will have to be analyzed to demonstrate their structural and geomorphic stability. The stability of backfilled facilities will also require analysis, at least of typical situations. In potentially unstable sites, simply backfilling cuts to original configuration may not result in a stable surface. Because of the unique peak strength versus ultimate strength relationships commonly characteristic of landslide-prone materials, once disturbed the placement and recompaction of these materials may not recover their original pre-disturbance strength. Particular attention will also have to focus upon the drainage of reclaimed areas and facilities, because of the deleterious effects of introduction of water to landslide landforms. In the case of the Mount Gunnison No. 1 mine, stability analyses determined that many of the retaining walls along roadways and portal bench cuts need to be backfilled in place to attain stable final reclaimed slopes. 72. Referring to map No. 18, Postmining Topography, and map no.