CX-019613: Cascade Steel Tap to Carlton-Sherwood #1 Impairment Removal Project (Update to previous categorical exclusion issued December 14, 2018)

Bonneville Power Administration has identified a transmission line clearance impairment on the Cascade Steel Tap to Carlton-Sherwood #1 transmission line near the Bonneville Power Administration Carlton Substation. At this location, the Cascade Steel Tap to Carlton-Sherwood #1 line is too close to the Bonneville Power Administration Forest Grove McMinnville #1 line. The categorical exclusion issued December 14, 2018, proposed to increase the clearance between the two transmission lines by installing a single pole and associated features (guy wires, cross-arms, insulators, etc.) between Carlton Substation and structure 11/1 of the Cascade Steel Tap to Carlton-Sherwood #1 line. Bonneville Power Administration now proposes to replace Forest Grove-McMinnville #1 Structure 19/8 with single steel pole that would be ten feet shorter, and located in the same location as the existing pole structure. The new steel pole would be installed within a vertically-buried, four-foot diameter by ten-foot long, corrugated metal culvert. The pole would be bedded in crushed rock and native excavated material within the buried culvert. Excess excavated material would be spread in an upland location on-site and managed with appropriate erosion and sediment control best management practices, or hauled off-site to a facility that accepts this material. All project activities would take place on Bonneville Power Administration fee-owned property, and would use traditional transmission line equipment (digger-derrick, back hoe, bucket truck, work trucks, etc.).