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Vantage to Pomona Heights Chapter 2 230 kV Transmission Line Project FEIS Proposed Action and Alternatives PAGE 2-24 access of equipment from roads and trails without requiring them to travel long distances on the ROW corridors and would be located in more level areas so that blading would not be required. Turn-around areas would be required in certain areas along the ROW corridors where construction travel would be restricted by rock outcrops, washes, ravines, canals, or sensitive habitat and cultural areas. The turn-around areas would be located at the last structure that can be accessed by the road, as well as the first structure on the other side of the restricted access area. Turn-around areas typically occupy an area of 60 feet by 60 feet (3,600 sq. ft.). Specific structure locations, work areas, and set-up sites would be identified in the POD once detailed engineering design for the final selected route is available. 2.2.3.4 Pole and Foundation Installation Wood and Steel Structure Direct Burial Generally, pole excavations would be created with a vehicle-mounted power auger. Where conditions require the installation of pole foundations, excavations would be created with a backhoe or vehicle- mounted power auger. In extremely sandy areas, soils may be stabilized during excavation through the use of water or a gelling agent. An example of a gelling agent is “Novagel™” which acts as a viscosifier and soil stabilizer so that during foundation drilling the sidewalls do not collapse during the drilling process. After excavation is complete, the structures would be put in place by direct burial. Excavation activities would require access by the necessary equipment, including power auger or drill, crane, and material trucks. Poles would be placed in holes or foundations as soon as the holes are ready. In rare instances where holes are left open for any period of time, they would be covered and/or fenced to protect the public, livestock, and wildlife. Soils removed from holes would be stockpiled on the work area and used to backfill holes. All remaining soil not needed for backfilling would be spread on the work area unless otherwise directed by land owner or land manager. Single Steel Pole and Steel Lattice Structure Foundations Some single steel poles and the steel lattice structures for the Columbia River crossing would require the installation of foundations which are typically drilled concrete piers. Holes for the foundation would be drilled using truck or track-mounted augers. Reinforced steel anchor bolt cages would be installed after excavation and prior to structure installation. These cages are designed to strengthen the structural integrity of the foundations and would be assembled at the nearest proposed Project laydown yard and delivered to the structure site via flatbed truck. These cages would be inserted in the holes prior to pouring concrete. The excavated holes containing the reinforced anchor bolt cages would be filled with concrete. Chute debris from concrete trucks would be washed into the excavated holes. 2.2.3.5 Wood Pole Assembly and Erection Wood poles and associated hardware would be delivered to each pole work area by truck. Insulator strings and stringing sheaves would then be installed at each ground wire and conductor position while the pole is on the ground. Stringing sheaves would be used to guide the conductor during the stringing process for attachment onto the insulator strings. The assembled structure would then be hoisted into place by a crane or line truck. Figure 2-6 illustrates typical pole assembly activities.