The South Sioux City to Sioux Falls A-line Replacement will allow Northern to abandon in-place approximately 79 miles of its 14-inch-diameter M561A branch line (A-line) and, to replace the lost capacity, install 84.15 miles of 12-inch-diameter A-line between South Sioux City, Nebraska, and Sioux Falls, South Dakota. The majority of the replacement A-line will be installed within a 25-foot offset from the existing A-line with the exception of three areas – the replacement pipeline route will (1) be installed around Elk Point, South Dakota, to avoid multiple crossings of Interstate 29; (2) deviate from the existing pipeline where the pipeline crosses the Missouri River in Dixon County, Nebraska; and (3) deviate from the existing pipeline where the new A-line ties into Northern's B-line at the southern end of the route near Harrisburg, South Dakota.
In addition to the A-line replacement, Northern proposes to replace its Ponca branch line. The 0.2-mile-long 2-inch-diameter Ponca branch line, which currently ties into the A-line to be abandoned, will be abandoned in-place and replaced with two miles of 3-inch-diameter branch line. The extended length and larger diameter is necessary in order to tie the new Ponca branch line into the replacement A-line at a location optimal to meet required pressure profiles. The line will parallel approximately 1.5 miles of the existing A-line and 0.5 mile of the existing Ponca branch line, and terminate at Northern's existing Ponca town border station.
Following the abandonment of the pipeline and the restoration of the land used for the pipeline project, Northern intends to offer the abandoned pipeline to a salvage company. The salvage company will be required, by contract, to comply with federal regulations regarding land restoration and sensitive environmental resource protection.
On July 23 2019, the Federal Energy Regulatory Commission approved Northern's application to use the Commission's pre-filing process. The approval, which has been docketed at the Commission at PF19-8-000, requires Northern to implement a Public Participation Plan that will involve open houses and other outreach opportunities, as needed, with affected landowners and other stakeholders. Northern plans to file its section 7 application for approval to start the project in July 2020. Northern is anticipating that approval for the project, subject to Commission review, will occur in March 2021. The facilities are scheduled to be placed into service November 1, 2021.