American Transmission Company (ATC), in a July 24 quarterly progress report for the period April 1 through June 30 filed with Wisconsin regulators, said that its Boscobel to Lone Rock (Line Y124) Rebuild Project is on schedule for substantial completion of the Y-124 rebuild in December 2019.
As TransmissionHub reported, the Public Service Commission of Wisconsin last September told ATC that the company’s request for an extension of time to begin construction on the Boscobel to Lone Rock project is granted.
“Order Condition 17 of the above-stated final decision is revised to require starting date for the subject project by June 1, 2018,” the commission said. “All other conditions of the commission’s September 17, 2016, final decision remain unchanged.”
ATC, in an Aug. 30, 2017, filing made with the commission, requested an extension until June 2018 to begin construction on the project.
As noted in that filing, the commission granted to ATC a certificate of authority, effective Sept. 17, 2016, to rebuild its 69-kV transmission line between the Boscobel and Lone Rock substations. Condition 17 of the order granting the certificate requires ATC to request an extension and receive approval if construction will not begin within one year of the effective date of the order, the company noted.
ATC said that as described in its application and the commission’s order, the company intended to begin construction in June by starting ROW clearing activities. The company added in its filing that it intended to begin construction in late 2017, or early 2018 with ROW clearing.
The requested extension would allow additional time for permitting and easement acquisition, and would better align ROW clearing activities with Order Condition 12, which requires the company to consider modifying its schedule to perform vegetation management activities during winter months when vegetation is dormant, to mitigate impacts.
The company added that the requested extension would not impact the approved project cost or change the planned December 2019 in-service date.
The commission, in its September 2016 final decision, granted, subject to conditions, ATC’s application for authority to rebuild about 25 miles of the existing 69-kV transmission line between the existing Boscobel substation in the city of Boscobel, Grant County, and the Lone Rock substation in the town of Buena Vista, Richland County.
Other than rerouting the line in two segments for a total distance of about nine miles, the existing line will be rebuilt within its existing ROW, the commission said in its decision.
The operating voltage of the line will remain at 69 kV, the commission said. ATC proposes to rebuild about 25 miles of the existing 27.6-mile line, the commission said, adding that the company and its predecessor transmission owner have performed maintenance rebuilding on the remaining 2.6 miles of the line during the past 20 to 30 years. On that section of the line, ATC proposes to selectively replace additional facilities following regular maintenance inspections, the commission said.
In its July 24 filing, ATC noted that Muscoda Utilities recently initiated a project to expand its industrial substation. ATC said that it will delay the rebuild of a short section of Y-124 in the vicinity of that substation to avoid rework and additional construction cost.
The substation expansion is in the very early planning stage, and the transmission line design needed to accommodate that expansion is unclear, ATC said. The gap in the Y-124 transmission line rebuild will be completed with the substation expansion project, which is planned for construction in 2020 or 2021.
All major permit applications have been submitted, and permits received since the last report include a utility permit from the Lower Wisconsin State Riverway Board and an erosion control permit from the Wisconsin Department of Natural Resources.
Detailed design activities for the transmission line portion of the project are nearly complete, ATC said, adding that the final construction drawings and specifications are under review.
Concrete foundation work for that portion of the project is planned to begin in late August, and the remaining vegetation management activities will be completed in the fall.
ATC also said that detailed design activities for the substation portion of the project are nearly complete, and the final construction drawings, as well as specifications, will be issued for review this month.
Actual project costs as of June 30 were about $6m out of the approved $32.4m, the company said.