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Section 3.0: Drainageway reconstruction and repairs at Trapper Mine in 1987 Permanent drainageway construction and subsequent control of excessive gully formation is important to successful vegetation recovery on disturbed mined land. The discharge of flows during snow melt and rain storms into newly established waterways may result in excessive gully formation without adequate control measures. Excessive gullies is associated with accelerated erosion and therefore with landscape instability. Recognizing this problem, Trapper Mine initiated an ambitious erosion control program in an attempt to reduce and/or eliminate excessive gully formation in reestablished drainageways. Section 3.1: Drainage Reconstruction in 1987 Portions of four major drainageways were regraded and appropriately treated to reduce the erosion rate and assist in permanent gully stabilization in 1987. Erosion control techniques were applied in Coyote, East No-Name, West No-Name and Johnson Gulch drainages and included 23,050 feet of permanent drainageway treatments. (See the enclosed map 3-1, "Drainage Reconstruction" for approximate locations of treated drainageways in 1987). A wide variety of erosion control materials and methods were used in each drainageway warranting a separate discussion for each. Table 3-1 lists the linear amounts of drainage treated in each of the four watersheds. Coyote Approximately 13,000 feet of drainage was reconstructed and adequately treated in ~ 1987. Nine thousand-one hundred feet were regraded and topsoiled to a depth of v approximately 6 inches. Following topsoiling, erosion control structures (hay bales, rock and vegetation) were keyed in at approximately 12.5-ft to 50-ft intervals in the drainage channel. All rock structures were installed using an appropriate cloth lining. Approximately 350 hay bale structures, 350 vegetation structures (native willow bundles) and 50 rock structures were constructed. Additionally, a 400 foot segment was treated with geoweb soil confinement material (4" and 8") to protect a critical area in the drainageway. All areas were drill seeded with an appropriate perennial seed mix for long term vegetation establishment. A sterile, hybrid perennial grass, drilled at a rate of 20dk/acre, was also used as a cover crop to establish a short term vegetation cover. The drainage channel and associated side slopes were mulched at a rate of 1500ik/acre using a grass-forb hay mix as residue. Following mulching, landglas erosion control fiber was applied (.35i)/yd2) and tacked using an emulsified asphalt solution (.35 gal/yd2) to stabilize and trap sediment on the soil surface. Additional erosion control in Coyote drainage included seeding of rills and small gullies on adjacent reclaim areas, and the placement of hay bales in an adjoining tributary (west of the major drainage -3900') to reduce the erosion potential and increase vegetation cover. Rock armoring was installed downstream of several eroding hay bale structures providing an apron to eliminate future cutting associated with light ephemeral flows and pit de-watering. Several