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Vantage to Pomona Heights Chapter 2 230 kV Transmission Line Project FEIS Proposed Action and Alternatives PAGE 2-21 construction. All roads, bridges, and other such infrastructure existing prior to construction would be left in a condition equal to or better than the condition prior to construction. Wherever existing roads could be used, only spur roads to structure sites may need to be constructed. In some areas, only temporary roads would be needed. Typically, these temporary roads would be graded to a travel surface width of approximately 14 feet minimum (up to 24 feet maximum) depending on terrain. Turnout areas and curves in the road would require a wider surface width. Normally, a ditch drainage system would not be constructed for temporary roads; however, best management practices and required design features (RDFs) would be implemented to control erosion and other resource protection concerns, such as placing water bars in the road. Permanent access roads would be constructed where needed for construction and long-term maintenance. Permanent access roads would be graded to a travel surface width of approximately 14 feet minimum (up to 24 feet maximum) including road prism and cut/fill area depending on terrain and radius of road curve. Turnout areas and curves in the road would require a wider surface width. Culverts or other drainage structures would be installed as necessary across drainages, but the roads would usually follow the natural grade. Wherever possible, roads would be built at right angles to drainages. Clearings for construction of new roads or maintenance of existing roads typically occur five feet beyond the edge of the roadway on level ground. On hillside cuts or fills, clearings would be sufficient width to install the cut or fill without interference. According to Pacific Power’s road development standards (PacifiCorp 2008), where side slopes exceed 60 percent, a full bench cut would be reburied to stabilize the slope bases. No side-casting of material would be allowed in these areas; end-haul of material (dump areas of removed earth where necessary) would be required to a designated location as approved by the landowner or land management agency. The level of ongoing maintenance of permanent roads would be determined by Pacific Power’s local maintenance and operations crews in accordance with state and federal agency stipulations and local landowner agreements. Overland access would occur in areas where no grading would be needed and would be used to the greatest extent possible. Overland travel would consist of “drive and crush” and/or “clear and cut” travel. Drive and crush is vehicular travel to access a site without significantly modifying the landscape. Vegetation is crushed but not cropped. Soil is compacted, but no surface soil is removed. Clear and cut is the removal of vegetation in order to improve or provide suitable access for equipment. Vegetation is removed using above ground cutting methods that leave the root crown intact. Soil is compacted, but no surface soil is removed. In areas of dense vegetation, the surface organic material would be stripped from the ground within the roadway and cut or filled in some areas. Stripping would occur to a maximum depth of six inches unless it is necessary as deemed appropriate by the engineers (Pacific Power, state, federal, and/or local agencies, as appropriate). The stripped area would be compacted as necessary to provide an adequate surface. In certain areas, it could be necessary to block/close roads after construction to restrict future access for general public and undesired use. Such areas would be identified through negotiations with the landowner or land management agency. Methods for road closure or management may include installing locking gates or obstructing the roads with earthen berms or boulders. Blocked/closed access roads would have to be reopened, when necessary for Project maintenance, repair, inspection, etc. For the purposes of calculating estimated access road disturbance created as a result of the Action Alternatives for route segments with overhead and underground construction standards, eight levels of access (Access Levels 0 through 7) were developed). These Access Levels were based on the development standards detailed above and were numerically arranged based on the anticipated ground disturbance expected with Level 0 having the lowest ground disturbance per mile of transmission line and Level 7 having the most. The Access Levels incorporate the presence of existing roads, an assessment of