_GENERAL DOCUMENTS - C1981017 (247)

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facility. As vegetation becomes established, the ditches will be allowed to breach. Significant erosion is not expected to occur at that time. Of greater concern is Ditch 8, which traverses down the south face of the facility. This steep ditch has not stabilized, and remains problematic. A repair was implemented in October, 1996, which may help to alleviate the problem. The liner installed in Ditch 1 , per the approved reclamation plan, was considerably undersized for the drainage dynamics. It has been removed from the ditch. The Old Refuse pile appears to be relatively stable, however, long term drainage concerns need to be addressed. This should be accomplished when the facilities area is reclaimed. Initial observations indicate that revegetation efforts at both facilities were marginally successful. A prolonged rainless period in late spring may have hampered revegetation success. Mine 3 : The land form created at the highwall and from the borrow area east of the wall appears stable. Sloughing from the top of the highwall onto the backfill is blending the cliff face and backfill into a natural looking talus like slope. The area of the fill which experienced the depression failure in 1995 has not reopened, however a slight depression appears to be forming at this location. This area will be monitored in 1997. The leveling of the north facing outslope crest from a nearly vertical edge to a 5h:1V slope, along with the construction of retention furrows, appears to have successfully encouraged sheet flow from the bench. Significant erosion of the north slope gullies was not observed in 1996. The use of the furrows on the south east side of the bench appears to have been similarly successful. The vegetation on the fill and borrow areas was sparse through mid- summer. However the advent of afternoon showers in July through September contributed to increased germination in these areas. Unfortunately a wide variety of weeds were observed as well. These are thought to have been introduced with the mulch used at this site. The hydroseeded outslopes enjoyed varying degrees of success. These slopes were hydroseeded a distance of about 300 feet downslope. Through mid-summer, neither the north or south east slopes appeared to support any degree of newly introduced vegetation. However, by late August, vegetation on the north slope was visible from the Mine 5 fan area. Hydroseeding of the south east slope does not appear to have been successful. Mine 4: The land form created at the highwall and at the borrow areas on the outslope crests appear to be stable. The leveling of the north and east facing slope crests from a nearly vertical edge to a 5h:1V slope, along with the construction of retention berms appears to have successfully encouraged sheet flow from the bench. 9