TransCanada Corp.’s Columbia Gas Transmission LLC (TCO) has requested FERC’s approval to construct and operate the Buckeye XPress Project in Ohio and West Virginia, which would add another 275 MMcf/d of natural gas capacity to the interstate pipeline system.

Buckeye XPress would include replacing 60.8 miles of aging 20- and 24-inch diameter pipeline with 66.2 miles of 36-inch pipeline in southern Ohio’s Vinton, Jackson, Gallia and Lawrence counties, as well as in western West Virginia’s Wayne County. The project, primarily designed to increase safety and reliability, would replace portions of TCO’s R-system, which was constructed in the 1940s.

The R-system, which supports more than 1 Bcf/d of primary firm transportation, is critical to TCO’s storage operations, according to the application. It provides the main path for gas to move into Ohio for summer storage injections and allows a way for gas to move southward from the Ohio storage fields in the winter.

“The use of the larger diameter replacement pipeline will allow Columbia to be ready to meet an anticipated growth in transportation demand from the Appalachian production area to delivery points in Kentucky and West Virginia, with only minimal additional environmental and landowner impacts,” TCO said in the application. “In fact, no new landowners will be impacted by the upsizing of the pipe for the project.”

TCO launched a nonbinding open season for the project in January 2017, envisioning a larger project at the time. It started the pre-filing process at the Federal Energy Regulatory Commission last August.

Buckeye XPress is expected to cost $709 million. In addition to replacing the old pipe, the project would add four mainline valves, four tie-in assemblies, installation of a regulation run at the existing Ceredo compressor station, and two sets of bidirectional launchers and receivers. The additions would help increase transportation capacity to its Leach, KY, interconnection with the Columbia Gulf Transmission system and the TCO pool market in the West Virginia region.

TCO requested authorization for the project by Jan. 31. The target in-service date is Nov. 1, 2020.