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. Attachment A <br /> of vegetation and are subject to significant erosion, as evidenced by the well developed gullies which <br /> are common on each slope. Soils are essentially non-existent on the slopes. <br /> Quantitative measurements of sediment generation from the various slopes have not been made. <br /> Visual observations, however, confirm that these areas are significant areas of sediment generation. <br /> Please refer to the attached photographs. <br /> It is apparent that the timing of sediment delivery from the outslopes to the adjacent streams is <br /> coincident with spring snow melt and runoff from summer rain events. <br /> 3.0 PROJECT DESCRIPTION <br /> 3.1 The goals of the project are to minimize erosion of five mine bench outslopes, to minimize <br /> transport of sediment which is generated from the mine bench outslopes, to demonstrate that cost- <br /> effective, low maintenance methods of accomplishing erosion control and sediment containment are <br /> achievable at high altitude locations, and to disseminate information relevant to high altitude <br /> sedimentation and erosion control to the public, local land use planners and scientific communities. <br /> In order to facilitate successful completion of the Project, research, including assessment of a site <br /> where similar work has been attempted, will be accomplished. <br /> To accomplish these goals, a measure of the degree of current sedimentation will be recorded. The <br /> slopes will be scarified and prepared for seeding by construction of small benches for seed <br /> establishment purposes. Revegetation efforts, including application of seed and soil amendments, <br /> will be undertaken. A hay mulch will be applied to the surface to act as a protective cover for the <br /> seed. Vegetative sediment barriers will be constructed at the base of the slopes. <br /> Timing of seed application is critical. The Project will be scheduled for late September and early <br /> October. Test plot results indicate best success is achieved when revegetation can be accomplished <br /> between the light fall snow storms which blanket Coal Basin. A light snow immediately after <br /> distribution of the hay mulch helps bond the seed to the soil surface and promotes retention of the <br /> mulch on the slope. Further, seeding during this period of the year minimizes the potential of rains <br /> washing seed off the slope. The contract for the construction work shall be crafted so that flexibility <br /> is provided, in order to ensure that revegetation occurs during these optimal weather patterns. <br /> Construction of wetlands areas at the base of suitable outslopes and planting of shrub barriers at <br /> other locations will help minimize further transportation of sediment from the slopes. This is an <br /> effective sediment control method, which will be particularly useful until the vegetative cover is <br /> established. Public involvement will be solicited to help in the planting efforts. This will build an <br /> effective partnership with affected local residents and provide educational opportunities. <br />