Cheatham County Generation Site EIS Scoping Report
boom trucks, and forklifts. The result of this work would be that the existing conductor would be raised to provide the proper ground clearance. Disturbance would usually be limited to an approximately 100-foot-radius around the work structure. • Conductor Modification. Conductor modifications include conductor slides, cuts, or floating dead- ends to increase ground clearance. A cut involves removing a small amount of conductor and splicing the ends back together. A slide involves relocating the conductor clamp on the adjacent structure a certain distance toward the area of concern (i.e., “sliding” the clamp). No conductor would be removed. A floating dead-end shortens the suspension insulator string of a structure to gain elevation at the attachment point of the conductor, increasing a span’s clearance. These improvements would require the use of a bucket truck; disturbance would be minimal and confined to the immediate area of the clearance issue. • Conductor Replacement: If the existing conductor size cannot support the TL’s electrical load, the conductor must be replaced. Bucket trucks or other light-duty equipment would be utilized for access and stringing equipment. Reels of conductor would be delivered to various staging areas along the ROW, and temporary clearance poles would be installed at road crossings to reduce interference with traffic. The new conductor would be connected to the old conductor and pulled down the TL through pulleys suspended from the insulators. A bulldozer and specialized tensioning equipment would be used to pull conductors to the proper tension. Crews would then clamp the wires to the insulators and remove the pulleys. Wire pulls vary in length but are limited to a maximum of five miles. Pull point locations depend on the type of structures supporting the conductor as well as the length of conductor being installed and are typically located along the most accessible path on the ROW (adjacent to road crossings or existing access roads). The area of disturbance at each pull point typically ranges from 200 to 300 feet along the ROW. • Adding Surcharge. Adding rock or dirt (surcharge) to structure footing would sometimes be required when height and/or loading modifications are made to a structure. These changes can create uplift on the existing tower footings or grillage, therefore requiring a stone base settlement to be placed around the existing footings. The additional burden prevents the tower from rising under certain conditions (i.e., weather conditions or conductor loading). Typical installation of surcharge would be performed with tracked equipment with minimal ground disturbance. The stone would be piled around the footings as required. The depth varies depending on the uplift on the affected structures. • Modification of Local Power Company Distribution Lines. Local utilities’ distribution lines can intersect TVA TLs. If the local utility crossing does not have adequate clearance, TVA requests that the local utility lower or re-route the crossing. • Fiber Optic Ground Wire Installation. New fiber optic line can be installed with the help of a helicopter. Designated pull points along the TL corridor are used to set up cable reels of optic ground wire for installation. Pull point locations are typically located along the most accessible path on the ROW (adjacent to road crossings or existing access roads). Modifications to the existing TL are typically required along the length of the TL. Existing access roads would be used for the pull point locations. • Access Roads. Development of new permanent access roads to support upgrades to the existing TLs may be needed. Depending on access needs, existing access roads may require modifications such as brush clearing or tree trimming to allow for passage of equipment and
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