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Coal Me(hane Droina,Qe Project - Pane6 1G-24 Wett Elk Mine 3.1.2.2 Effects Common To Alternatives 2, 3, and 4 3-7 Soil removal, stockpiling, and replacement, along with consequent compaction and erosion would change soil characteristics in affected areas. Although disturbed areas can be reclaimed and rehabilitated, the soil productivity will be changed Erom its natural state. In Alternative 2, 3, and 4, approximately 54 temporary drill pads would be constructed for drilling and operation of 70 MDWs. Drill pad surface areas would typically be approximately 0.5 acres and construction related disturbance for each pad would average approximately 0.7 acres (0.5 w/40 percent additional for cut/fill). Surface disturbance for drill pads would be approximately 37.8 acres. Geologic hazard mapping indicates that 13 drillholes on 7 drill pads and two road segments would be located in or adjacent to high geologic hazazd areas, where surface occupancy and use would be precluded or restricted under the NSO stipulation for high geologic hazards. Table T3, Drill Pad Stipulation Effects Summary, and Table T4, Road Stipulation Effects Summary, display the affected drill pads and roads. Short segments of several access roads cross steep slope areas. .Most of these segments aze on existing roads and the segments crossing steep slopes aze short. Proposed roads or road segments would also cross moderate slope areas. These locations aze displayed on Map 1, Project Area Activities With Surface Stipulations. Road locations would be checked in the field by USFS personnel and if any changes or improvements are made to an existing road that crosses the steep slope areas, the steep slope stipulation would apply. If a proposed new road were proposed to cross a steep slope area, consideration would be given to adjusting the road alignment to avoid the steep slope azeas) or an exception to the stipulation would be necessary. If an exception is granted, the stipulations for moderate slopes would be applied. Construction of the new road would need to comply with specific design and mitigation measures described in section 2.4 of this EA. Slope mapping indicates that a total of 16 drill pads and 23 MDWs would be located in or adjacent to ' steep slopes (greater than 60 percent) where surface occupancy and use would be precluded under the NSO for slopes >60 percent lease stipulation. In addition, a total of 36 drill pads and 50 MD Ws would be located in or adjacent to moderate slope areas (40 to 60 percent) where specific design and mitigation measures would be applicable under the CSU for slopes 40-60 percent lease stipulations. Table T3, Drill Pad Stipulation Effects Summary, and Table T4, Road Stipulation Effects Summary, display the affected drill pads and roads. Segments of proposed access roads in Sylvester Gulch, East Fork Sylvester Gulch, and Box Canyon may be located at the foot of steep slopes in the nazrow drainages. These locations are displayed on Map 1, Project Area Activities With Surface Stipulations. There is a risk in these azeas of soil slumping due to construction activities. Construction could result in surface instability and erosion, as well as problems in constructing, maintaining, and reclaiming roads and drill pads. Where project- related construction would occur in geologic hazazd or steep slope areas, exceptions to the applicable stipulations would be necessary. USFS field construction review would focus on modification of the proposed road to shift its location or change its configuration to avoid restricted azeas or minimize impacts. In addition, specific design and mitigation measures would be effective in mitigating potential environmental effects. The Conditions of Approval listed in Section 2.4 of [his document include many measures designed to minimize soil disturbance. Despite these practices, erosion, soil loss, and sediment transport from newly disturbed azeas would still affect nearby drainages. Depending on proximity to streams and the amount of sediment cazried by mnoff, surface water quality (turbidity and suspended solids) could be temporarily impacted. IP.iPP/A/r4i ldG/F~1/D~ 1/a/~).l.I l~2Ff 3/S/OIA r.'nNNRn/Lnta[ft1fLSS)nenl