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were established using native seed collected at the mine. A new method of preparing the long, <br /> steep mine bench outslopes for revegetation was implemented on three acres of steep outslopes <br /> near Mine 1. A small native grass and forb 'nursery' was established, and an agreement for a <br /> private seed company to grow native plants collected from local seed sources was established. <br /> Additionally, due to concerns about grazing, about 18 acres of the Sutey Refuse Area was fenced <br /> to exclude cattle from that reclaimed area. Maintenance was accomplished at the site in the <br /> summer and fall to repair damage incurred as a result of spring run off and intense summer rain <br /> storms. <br /> In 1997, reclamation of the Warehouse vicinity and of the steep slopes below Mine 4 was <br /> accomplished. The Warehouse Vicinity Project included a great deal of concrete demolition and <br /> disposal at the former location of the three warehouses, at Coal Stockpiles B and M (located <br /> adjacent to Road A, about %2 mile past the Preparation Plant), and along the Overland Conveyor <br /> route. Backfilling and grading, as well as topsoil application in some areas and soil amendment <br /> incorporation in others was accomplished at each of the four major work areas. Due to the <br /> slopes involved, and, in the case of the Overland Conveyor, due to inaccessibility, most of the <br /> eighteen acres were hand seeded and mulched. <br /> Because of the steepness and height of the back walls at coal stockpiles B and M, long backfilled <br /> slopes were created during the reclamation process. In order to alleviate the potential problem of <br /> rilling and gullying occurring at these locations, methods to break up the surface were <br /> considered. Ultimately, the contractor was directed to create a series of depressions and berms <br /> across the face of each backfill. These generally measure eighteen inches from base to crest, and <br /> are about five feet in width. These were constructed throughout the backfilled coal stockpiles <br /> prior to initiating revegetation. These features will not only break up water drainage patterns <br /> sufficiently to minimize gully formation, but the depression portion of the features will act as <br /> collection areas for organic matter and water, and will ultimately act as points of soil generation. <br /> The Mine 4 Steep Slope Revegetation Project was directed at stabilizing the approximately <br /> twelve acres of mine bench outslopes through revegetation processes. A number of techniques <br /> which had been used over the past two years on a smaller scale were specified for <br /> implementation during completion of this Project. An organic, spray-on erosion control mat was <br /> applied to the upper portion of the mine bench. This material, initially experimented with on 1/4 <br /> acre in 1995, holds soil particles in place, while permitting seed sown prior to application to <br /> germinate and grow through the material. The erosion potential of the slopes below the treated <br /> area will be reduced as water flow patterns of the treated area immediately uphill are disrupted <br /> by stabilized soils and increased vegetative growth. <br /> Small benches were created in other areas using a modified roller designed by the contractor and <br /> Division staff. This technique had worked well in other areas, but it did not prove effective at <br /> Mine 4. The volume of large rock present on the outslope significantly diminished the <br /> effectiveness of this technique, and it was ultimately abandoned. Hand seeding and hydro- <br /> seeding of the slopes were employed at various locations. Straw mulch was blown onto the <br /> 4 <br />