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• Brush matting (crimping) is essentially a mulch of hardwood brusfi crimped into existing drainage cuts. The technique is employed very effectively in stream channels and on stream banks to protect against accelerated erosion rates when a channel needs repair. Geotextiles, erosion blankets and other erosion control fabrics, are used effectively in reducing stream velocities and increasing sedimentation in drainageways. A variety of materials are used at Trapper Mine and include geoweb - a soil confinement system, C125 coconut blanket , landglas erosion control fibers (landglas is tacked with CSS-1 emulsified asphalt), fibron fibers, mirifi erosion cloth, jute erosion netting and miramat blanket. 3.4 Improvements and Repairs Drainageway improvements and repairs were performed to provide benefits to all drainages treated in 1987-89, as well as portions of undisturbed drainage segments. Drainage improvements included the installation of several thousand shrub seedlings in 1987-88 treatment areas, the rock armoring of a few hay bale structures in 1987 treated drainageways, and dozer basin construction in newly stripped topsoil areas and on regraded spoils. Drainage repairs and enhancement were conducted in all previous reconstructed drainageways (87-88) with a minimum of effort required to complete this task. Essentially no downcutting in drainage bottoms occurred, therefore efforts were directed at reinforcing potential problem areas. • Rock structures were installed at an average frequency of 30-75' throughout the recon- structed Johnson Gulch and East Buzzard drainage in 1989. 3.5 Reconstructed Drainageway Profiles (As-Built) Due to adverse weather conditions following final drainage reconstruction, as-built pro- files were not conducted for 1989 segments. As-built profiles will be submitted to the Division for 1989 drainage reconstruction in late spring of 1990. No profiles for drainage repairs in previous reconstructed segments vnll be submitted to the Division as minimal/no repairs occurred. 3.6 Permanent Diversion Establishment As mentioned in a previous section, livestock watering tanks are often constructed on water harvesting diversions to trap water on reclaimed sideslopes and make available reliable water for wildlife/livestock use. To increase the amount of water available to livestock tanks, appropriate water har- vesting diversions may be removed immediately above the target diversion. The rema~mng diversion and stock tank would be permanent landscape features. Perma- nent water harvesting diversions are shown on the "Drainageway Reconstruction" map. 3.7 Results Vegetation response, decreased flow rates and reduced gully formation were the pri- • mary factors in assessing the success of drainage reconstruction projects at Trapper Mine.