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Vantage to Pomona Heights Chapter 2 230 kV Transmission Line Project FEIS Proposed Action and Alternatives PAGE 2-2 2.1 PROPOSED ACTION 2.1.1 New Overhead 230 kV Transmission Line Pacific Power proposes to construct, operate and maintain the new Vantage to Pomona Heights 230 kV Transmission Line from its existing Pomona Heights Substation east of Selah in Yakima County, Washington to the existing Bonneville Power Administration (BPA) Vantage Substation east of the Wanapum Dam in Grant County, Washington. Action Alternatives analyzed in this FEIS range in length from 40.5 miles (NNR Alternative – Overhead Design Option) to 66.9 miles (Alternative H), and are routed either through or to the south and east of the Joint-Base Lewis McCord Yakima Training Center (JBLM YTC; see Figures 2-1, 2-2, and 2-3). As proposed by Pacific Power, most of the proposed transmission line would be constructed on H-frame wood pole structures between 65 and 90 feet tall, typically, and spaced approximately 650 to 1,000 feet apart depending on terrain. The H-frame structures would typically be used in open flat to gently rolling terrain. In developed or agricultural areas, single wood or steel monopole structures would be used. The single pole structures would be between 70 and 110 feet tall and spaced approximately 400 to 700 feet apart. The right-of-way (ROW) width necessary/required for the H-frame structure type would range between 125 to 150 feet. The ROW width for the single pole structure would range between 75 to 100 feet. Dead-end or angle structures would require additional ROW width to accommodate guy wires and anchors. For the Columbia River crossing below the Wanapum Dam or below the Priest Rapids Dam (depending on the Action Alternative), steel lattice structures approximately 200 feet tall would be used to safely span the approximate 2,800-foot crossing. Illustrations of the structure types and typical design characteristics are presented in Section 2.2.2.1 and Figure 2-4. Final design characteristics would be determined in the detailed design phase of the proposed Project. Construction of the proposed transmission line would require vehicle, truck, and crane access to each new structure site for construction crews, materials, and equipment. Access along the transmission line ROW corridor would include existing roads in their current condition, existing roads that would be improved as part of this Project and new access roads. The proposed Project would use existing roads and trails wherever feasible to minimize the construction of new access roads. In areas that overland travel is not possible and where no roads are present, permanent new roads would be graded to a total width of between 14 and 24 feet (including both the travel surface and shoulders) depending on location and terrain. The roadway (cuts and fills) would remain for transmission line maintenance, but vegetation would be restored in accordance with agency requirements. Access would not be required from the Selah Cliffs Natural Area Preserve or Burkett Lake Recreation Area. During construction of the proposed transmission line, there would be temporary work areas at each structure site to facilitate the safe operation of equipment and construction operations. There would also be temporary work areas at pulling and tensioning sites, material staging sites, and turn-around areas. Work areas would require a temporary disturbance area of 150 feet by 125 feet (18,750 square feet [sq. ft.]/0.43 acre) for H-frame structures and 150 feet by 80 feet (12,000 sq. ft./0.28 acre) for single pole structures. Pulling and tension sites for stringing the conductor would require a temporary disturbance area of 125 feet by 400 feet (50,000 sq. ft./1.15 acres). Sites for pulling and tensioning would be located approximately every 11,000 feet (about 2.1 miles) or less.