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1987 treated drainageways, and dozer basin construction in newly stripped topsoil areas and on regraded <br />spoils. Drainage repairs were primarily in West No Name drainage and Upper Coyote drainage and included <br />the installation of several rock check structures and extensive rock rip-rapping (see "Drainage <br />Reconstruction' map). In addition, four livestock ponds were cleaned as required in our permit agreement <br />with CMLRD. <br />Several conservation practices performed in 1987 were not implemented in 1988 drainage reconstruction <br />and included hay bale structure construction, willow bundle installation and geoweb installation. Alternative <br />practices aimed too reduce costs and increase drainageway stability were implemented. <br />Rock structures were installed more frequently due to the increased slopes of treated drainage segments in <br />1988. The average frequency of rock structures ranged from 30-75' throughout the treated drainages. In <br />1987, rock structures were installed less frequently (50.100') and only in critical portions of drainages. <br />Brush matting was performed in a Bullied undisturbed segment of lower Coyote Drainage. Brush was <br />transported from pre-strip topsoil areas using 50-ton haul trucks and placed with a 988 loader. Following <br />loader placement, a backhoe was used to shape the drainage bottom and protect drainage sideslopes. <br />3.5 Reconstructed Drainagewav Profiles IAs-Builtl <br />Attachment A provides as-built profiles for drainages reconstructed in 1987 and 1988. In addition, <br />Attachment B includes profiles of drainage segments reconstructed in 1987 and repaired in 1988. <br />Attachment B profiles were resurveyed following appropriate drainage repairs. <br />• 3.6 Permanent Diversion Establishment <br />As mentioned in a previous section, livestock watering tanks are often constructed on water harvesting <br />diversions to trap water on reclaimed sideslopes and make available reliable water torwildlife/livestock use. <br />To increase the amount of water available to livestock tanks, appropriate water harvesting diversions may be <br />removed immediately above the target diversion. The remaining diversion and stock tank would be <br />permanent landscape features. Permanent water harvesting diversions are shown on the "Drainagewav <br />Reconstruction' map. <br />3.7 Results <br />Vegetation response and reduced gully formation were the primary factors in assessing the success of <br />drainage reconstruction projects at Trapper Mine. <br />Postmine herbaceous canopy cover, primary production, and woody stem density were evaluated in <br />reconstructed drainage areas in 1988 and compared to sample data from undisturbed premine drainage <br />areas. (Sampling was conducted on drainageways reconstructed in 1987). Various postmine drainage <br />treatments were incorporated to evaluate vegetation response on topsoiled, non-topsoiled, irrigated, and <br />non-irrigated drainage segments. Treatments on undisturbed areas were irrigated and non-irrigated <br />drainage segments. Vegetation cover, production and woody stem densities are reported in Table 2. <br />Generally, vegetation measurements were lower in reconstructed drainageways than 1n undisturbed <br />drainage sites. This is understandable due to the short duration of vegetation re-establishment. However, <br />considerable vegetation growth was reported in all reconstructed drainages after the initial growing season. <br />• <br />