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1999 Stabilization Project The North Basin Steep Slope Revegetation Project was originally bid in the summer of 1998. However, due to litigation pending at the time, the Project was suspended until 1999. During the interim, the Division was awarded aNon-Point Source grant from the Water Quality Control Division. This grant provided cash funding in the amount of about $121,000 to supplement the previously planned mine bench outslope revegetation project. The outslopes to be affected by this project included those located below Mine 1, Mine 1 Storage Bench, Mine 3 South, the lower portion of Mine 3 North and the Mine 5 Fan; an area totaling approximately twenty four acres in size. Construction Construction began in early September 1999. Using hand tools, approximately 3,000 shelves per acre were dug into the slopes. The shelves provide numerous slope breaks where seed can accumulate and germinate. Each shelf measured approximately ten inches wide by six to eight inches deep, and were constructed on three foot centers (horizontal and vertical). While one crew was created the shelves, a second crew collected and cleaned seed obtained from the locally occurring native grass Calamagrosti purpurascens. In addition, seed from a locally occurring aster (Aster glaucodes) was collected and cleaned. Seeding was accomplished as the crew worked down the slopes. The seed from the two native species as well as the commercially obtained seed (Table 1, Outslope Seed Mixture) was distributed on the slopes by hand broadcast methods. Using Calamagrostis seedlings grown from seed by the Upper Colorado Environmental Plant Center in Meeker Colorado, approximately two hundred grass tublings were planted across each of the five mine bench outslopes at mid-slope. The mid-slope area was chosen for planting, as it was anticipated that seed produced from the plants would have an equal chance of being distributed either up- or down-slope by winds. Bioso17-2-3, a slow release fertilizer, was applied by helicopter at a rate of 1,800 pounds per acre. Certified weed free straw mulch was applied at a rate of 2,000 pounds per acre. At four of the five outslopes, the mulch was applied by helicopter. The remaining outslope was mulched by hand because it was more readily accessible than the others. Approximately 540 containerized shrubs were planted at the base of each slope. The purpose of this planting was to establish vegetative sediment barriers at the toe of each slope. 4