_GENERAL DOCUMENTS - C1981017 (232)

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were established using native seed collected at the mine. A new method of preparing the long, steep mine bench outslopes for revegetation was implemented on three acres of steep outslopes near Mine 1. A small native grass and forb 'nursery' was established, and an agreement for a private seed company to grow native plants collected from local seed sources was established. Additionally, due to concerns about grazing, about 18 acres of the Sutey Refuse Area was fenced to exclude cattle from that reclaimed area. Maintenance was accomplished at the site in the summer and fall to repair damage incurred as a result of spring run off and intense summer rain storms. In 1997, reclamation of the Warehouse vicinity and of the steep slopes below Mine 4 was accomplished. The Warehouse Vicinity Project included a great deal of concrete demolition and disposal at the former location of the three warehouses, at Coal Stockpiles B and M (located adjacent to Road A, about Y2 mile past the Preparation Plant), and along the Overland Conveyor route. Backfilling and grading, as well as topsoil application in some areas and soil amendment incorporation in others was accomplished at each of the four major work areas. Due to the slopes involved, and, in the case of the Overland Conveyor, due to inaccessibility, most of the eighteen acres were hand seeded and mulched. Because of the steepness and height of the back walls at coal stockpiles B and M, long backfilled slopes were created during the reclamation process. In order to alleviate the potential problem of rilling and gullying occurring at these locations, methods to break up the surface were considered. Ultimately, the contractor was directed to create a series of depressions and berms across the face of each backfill. These generally measure eighteen inches from base to crest, and are about five feet in width. These were constructed throughout the backfilled coal stockpiles prior to initiating revegetation. These features will not only break up water drainage patterns sufficiently to minimize gully formation, but the depression portion of the features will act as collection areas for organic matter and water, and will ultimately act as points of soil generation. The Mine 4 Steep Slope Revegetation Project was directed at stabilizing the approximately twelve acres of mine bench outslopes through revegetation processes. A number of techniques which had been used over the past two years on a smaller scale were specified for implementation during completion of this Project. An organic, spray -on erosion control mat was applied to the upper portion of the mine bench. This material, initially experimented with on 1/4 acre in 1995, holds soil particles in place, while permitting seed sown prior to application to germinate and grow through the material. The erosion potential of the slopes below the treated area will be reduced as water flow patterns of the treated area immediately uphill are disrupted by stabilized soils and increased vegetative growth. Small benches were created in other areas using a modified roller designed by the contractor and Division staff. This technique had worked well in other areas, but it did not prove effective at Mine 4. The volume of large rock present on the outslope significantly diminished the effectiveness of this technique, and it was ultimately abandoned. Hand seeding and hydro - seeding of the slopes were employed at various locations. Straw mulch was blown onto the 4