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excavation in the toe area of the coal mine waste bank. It is <br />i possible the tow of the coal mine waste bank may require redesign <br />to provide a keyway, rock wall buttress, mechanically stabilized <br />earth section or a combination of these methods to provide proper <br />stability in this critical area. <br />If the top of the Rollins Formation is <br />between 6080' and 6090', as indicated by our surface reconnais- <br />sance of this site, the slope stability calculations prepared by <br />WESTEC would be based upon an improper cross section and <br />soil/rock profile. It is believed the majority of calculations <br />preformed by WESTEC would be on the very conservative side, as <br />the placement of the low strength Bowie Member of the Nesa Verde <br />Formation would be less extensive beneath the base area of the <br />• coal Mine waste Bank but, the stability of the toe area may be in <br />question. <br />It is believed that significant amounts <br />of top soil can be obtained from this site. It is also believed <br />that significant amounts of construction materials, principally <br />the alluvial gravels and cobbles, can be recovered prior to <br />placement of the coal mine waste. It is possible that the vol- <br />umes of the eastern portions of this waste pile may be somewhat <br />increased due to mining of usable gravels and cobbles. It is <br />recommended that signifiaant attention be given to the access <br />roads and final road construction at the east end of the waste <br />pile. It is believed that fill slope angles may be increased, <br /> with proper use of mechanically stabilized earth techniques and <br />• other slope retention measures. Such slope retention measures <br />7 <br />