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Vantage to Pomona Heights Chapter 2 230 kV Transmission Line Project FEIS Proposed Action and Alternatives PAGE 2-33 periodic replacement include insulators, hardware or structure members. It is expected that these replacements would be required infrequently. Pacific Power would safely conduct maintenance on the proposed 230 kV transmission using live-line maintenance techniques, which would avoid an outage to the critical transmission line infrastructure. For the 230 kV H-frame structures, this requires that adequate space be available at each structure site so that a bucket truck can be positioned to access the outside phases. To allow room at each structure for these activities in low slope areas, a pad area is required with the structure in the center of the ROW corridor. The size and location of these required pads near the structures may vary depending on the side slope and access road routes at each site. The work areas and pads would be cleared to the extent needed to safely complete the work. Wood poles are treated to retard rotting and structural degradation (e.g., Dazomet). Personnel access structures by pickup, OHV, or by foot; inspect and test (including the subsurface) the poles; and then treat them by injecting preservatives into the poles. Wood pole inspections and treatments occur on a 10-year cycle. 2.2.4.3 Right-of-Way Repair ROW corridor repairs include grading or repair of existing maintenance access roads and work areas and spot repair of sites subject to flooding or scouring. Required equipment may include a grader, backhoe, four-wheel drive pickup truck, and a cat-loader or bulldozer. The cat-loader has steel tracks whereas the grader, backhoe, and truck typically have rubber tires. Repairs to the ROW corridor would be scheduled as a result of line inspections or would occur in response to an emergency situation. 2.2.4.4 Vegetation Management Work areas adjacent to the proposed electrical transmission structures and along the ROW corridor must be maintained for vehicle and equipment access necessary for operations, maintenance, and repair including for live-line maintenance activities. Shrubs and other obstructions would be regularly removed near structures to facilitate inspection and maintenance of equipment and to ensure system reliability. At a minimum, trees and brush would be cleared within a 25-foot radius of the base or foundation of all electrical transmission structures and to accommodate equipment pads to conduct live-line maintenance operations. Vegetation within the linear area along the ROW corridor under the conductors and extending 10 feet outside the outermost conductor would be maintained to consist of grasses and low growing shrubs or short trees less than five feet tall at maturity. Every effort would be made to ensure that mature sagebrush is maintained intact as it typically does not exceed five feet in height. An area extending from 10 feet outside the outermost conductor to the edge of the ROW corridor would be maintained to consist of tall shrubs or short trees up to 25 feet high at maturity. When conductor ground clearance is greater than 50 feet, for example a canyon or ravine crossing with high ground clearance at mid-span, trees and shrubs would be left in place as long as the conductor clearance to the vegetation tops is 50 feet or more. Noxious weed control will be described in detail in the POD’s Noxious Weed and Invasive Plant Management Plan. This plan will be consistent with the Spokane District RMP and 1992 RMP amendment (BLM 1985; BLM 1992) and subsequent updated RMPs, JBLM YTC Noxious Weed Control Plan (JBLM YTC 2002), Executive Order 13112 (Invasive Species), the Federal Noxious Weed Act, and Washington State Noxious Weed Laws. The plan will describe the pre-construction inventory; prevention measures and treatment methods before and during construction; and monitoring and treatment measures that would be implemented following construction. If revegetation cannot be done immediately following