_GENERAL DOCUMENTS - C1981017 (231)

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JUL-27-1990 13:23 ROBERT DELANEY 970 945 2303 P. 11 97-Cv-131-3 07/21/98 � Page 2 and tree growth was noted. At the lower toe of the slope, a zone of sediment and debris flow accumulation was observed (Figure 2). On slopes such as this, reclamation would be best attempted through construction of sediment collection facilities (such as dozer basins at the toe of the slope), in concert with vegetation plantings along the toe of the slope and above and below the sediment collection facilities. Revegetation will not be successful on the steep upper segments of outslopes such as these. The strip area bench was inspected. This area was seeded in the early 1990's by CDMG under the AML program. Vegetation growth on the north and east sides of the bench area is fair to good, with the most successful species being bluegrass (poa species), which has formed large clumps on the north side of the bench. Orchardgrass was noted as present, but very stunted. Several additional species were noted as present in small numbers; mountain brome, American vetch, fescue, and groundsel. The Mine #5 fan bench and outslope were inspected. Vegetation growth on the bench and outslope was very sparse (Figure 3). Three factors likely account for this. The material available for plant growth is dark shale, the aspect of the bench and outslope is south, and the outslopes are very steep, appearing to exceed those of the north side of the strip area. The surrounding area is rock outcrop, also with little, if any, plant growth. The length of the Mine #5 fan bench outslope was estimated at 800 feet. Given the nature of the surrounding natural areas, it is very unlikely that revegetation efforts will succeed on this outslope (Figure 4). It was also noted that the vegetation test plots on the southeast-facing slope of the strip area have not shown successful revegetation results. Mine #3 On July 15, 1998, I inspected the Mine #3 access road, bin area, fan bench, portal bench, and outslopes. Though the access road had been reseeded, road culverts removed, and water bars installed, the area remained accessible by four-wheeler. Several cut slopes and outslopes along the Mine #3 access road are shaley or rocky in nature. Figure 5 illustrates an area where the road was seeded by CDMG in previous reclamation efforts, but regrowth has been sparse at best. If the plants will not grow on the flat road surface, plant growth will not occur on the steep slopes of the bench outslopes or road cut slopes or outslopes. These areas should be left as they are. Approaching the Mine #3 lower benches, material on the cut slopes and road outslopes is often shaley and dark, and though it is fine grained, little plant growth is present on this material (Figure 6). One road outslope illustrates (Figure 7) that on moderated slopes toward the base of the outslopes, a fair growth of plants can become established. At the edge of the road, at the angle of repose, no plant growth is observed. This is probably due to wind and water erosion, soil creep, exposure, and other environmental factors. Seeding the entire length of such a slope will not result in vegetation becoming established at the slope crown.