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The shrub enhancement areas were prepared for planting by selectively pre-treating existing <br />vegetation within the shrub enhancement "planting" areas with a broad leaf herbicide. Root stock <br />and sprigs (cuttings) were planted approximately one week following herbicide treatment. A woven <br />synthetic weed barrier was installed, as appropriate, over each individual planting site to minimize <br />herbaceous competition and enhance plant water availability. <br />The seedlings and/or cuttings were clumped into various groups to provide better cover for foraging <br />and nesting. The shrubs were planted at a minimum density of 1,000 stems per acre. Limited, <br />' supplemental plantings of black currant (gibes spp.) and Woods rose (Rosa woodsii) occurred in <br />1997. The planting areas were protected by 8-foot high woven wire fences to keep out elk, deer and <br />antelope <br />The planting areas were irrigated during 1996 and 1997. A sprinkler irrigation system was utilized <br />' in 1996. A salt residue on shrub leaves and adjacent soils was observed at the end of that first <br />growing season. To minimize effects from the high total dissolved solids concentration in the <br />' irrigation water, a flood irrigation system was used in 1997. <br />The success criterion was 750 stems per acre for Phase [II bond release of the three shrub <br />' enhancement parcels. <br />' Highwall Stability <br />A slump feature formed along the former highwall in 1992. The slump feature dimensions were <br />approximately 150 wide by 250 feet long and created a head scarp approximately three feet high. <br />The slump mass was approximately eight to 12 feet deep. The cause of the slump was believed to <br />be lubrication due to infiltration of water along the contact between bedrock and reclaimed spoils. <br />[n 1994, a French drain was installed above the head scarp to a depth of approximately 20 feet. The <br />French drain was designed to prevent or minimize the infiltration of water along the sliding surface <br />of the slump. Field observations conducted during the spring 1997 following snowmelt indicated <br />additional movement. <br />Further slump mitigation measures were completed in 1998. The additional measures included: <br />• An upper French drain to intercept subsurface water from the south and west, near the <br />upslope portion of the slump; <br />• A middle French drain to intercept subsurface water that may drain from the upslope portion <br />of the slump and/or collect in the middle portion of the slump; <br />Hayden Gulch ,Cline 2006 Award Nomination Page 3 <br />