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Vantage to Pomona Heights Chapter 2 <br />230 kV Transmission Line Project FEIS Proposed Action and Alternatives <br /> PAGE 2-22 <br />their current conditions, and the anticipated road construction based on slope and vegetation cover. Level <br />0 was assigned in areas where no ground disturbance is anticipated, such as the crossing of surface water. <br />Access Levels were assigned for each 0.1 mile increment along all segments (see Appendix A: Map 1 – <br />Access Map). Access levels are summarized in Table 2-3. <br />Table 2-3 Access Levels and Ground Disturbance (Overhead and Underground Construction <br />Standards) <br />ACCESS <br />LEVEL ACCESS SUMMARY DISTURBANCE ASSUMPTIONS <br />Level 0 <br />No Roads (at river crossing <br />or helicopter construction); <br />or Use Existing Improved <br />Roads. No Preparation <br />Required. <br />Crossing of the Columbia River (open water) and very steep terrain (helicopter <br />construction); urbanized areas with improved roads; no road construction <br />necessary. <br />Level 1 <br />Overland Access in Flat <br />Areas, Limited Disturbance <br />in Flat Terrain (0 to 8%) <br />Low ground disturbance for new access road construction; assume generally <br />overland access across grassy/low veg. areas and limited areas of grooming and <br />grading; 4 to 5 inches of crushed rock applied in limited areas. Assume 10% of <br />travel way graded, groomed, and/or graveled. <br />Level 2 Existing Improved Roads <br />Previously disturbed. Roads generally are in good condition, but may require small <br />improvements at stream crossings, steep slope areas, and other locations. New <br />ground disturbance would be minimal. New spur roads would be required to <br />access each structure site; an average of 300 feet of new spur road for each <br />structure. Spur roads would disturb approximately 0.4 acres per mile of <br />transmission line. <br />Level 3 Roads that Require <br />Improvement <br />Previously disturbed. Existing two-track or narrow unimproved roads would require <br />improvement to make roads serviceable (e.g., mowing, grading) for construction. <br />Low ground disturbance; assume approximately 0.5 to 1.0 mile of road <br />improvements for each mile of transmission line. Road improvements would <br />disturb approximately 0.75 to 1.0 acre per mile of transmission line. An average of <br />300 feet of spur roads would be required to access each structure site. Spur roads <br />would disturb about 0.4 acre per mile of transmission line. <br />Level 4 Construct Road in Flat <br />Terrain (0 to 8%) <br />Low to moderate ground disturbance for new access road construction; assume <br />approximately 1.0 to 1.2 miles of new roads would be required for each mile of <br />transmission line. Road construction would disturb approximately 1.7 to 2.0 acres <br />per mile of transmission line. <br />Level 5 Construct Road in Sloping <br />Terrain (8 to 15%) <br />Moderate ground disturbance for new access road construction; assume 1.2 to 1.5 <br />miles of new road would be required for each mile of transmission line. Road <br />construction would disturb approximately 2.0 to 2.5 acres per mile of transmission <br />line. <br />Level 6 Construct Road in Steep <br />Terrain (15 to 30%) <br />Moderate to high ground disturbance for new access road construction; assume <br />approximately 1.5 to 2.0 miles of new road would be required for each mile of <br />transmission line. Road construction would disturb approximately 2.5 to 3.4 acres <br />per mile of transmission line. <br />Level 7 Construct Road in Very <br />Steep Terrain (over 30%) <br />High to very high ground disturbance for new access road construction; assume <br />approximately 2.0 to 3.0 miles of new road would be required for each mile of <br />transmission line. Road construction would disturb approximately 3.4 to 5.0 acres <br />per mile of transmission line. <br />Access Assumptions: <br />1. Permanent new access roads would be graded to travel service width of 14 feet, including cut and fill. <br />2. Spur roads would be an average of 300 feet in length. <br />Access levels were assigned along the assumed Project centerlines of Action Alternatives by determining <br />the location and condition of existing roads within the proposed Project ROW corridors based on field <br />review and aerial photography analysis. During preliminary engineering, Pacific Power identified areas <br />where helicopter construction would occur due to extreme slope and access limitations for the Action