The project includes building a new substation; rebuilding the 115-kV M13 transmission line from the Bunker Hill switching station in Lincoln County, Wis., to the Blackbrook switching station in Langlade County, Wis.; uprating the 115-kV M13 transmission line from the Kelly substation in Marathon County, Wis., to the Blackbrook switching station; as well as retiring and removing the Bunker Hill and Blackbrook substations.
The route of the rebuild portion of the project begins at the Blackbrook substation in the town of Ackley, Langlade County, and follows the existing M13 line route west to the proposed Ackley substation in the town of Pine River, Lincoln County.
The rebuild would take place adjacent to the existing M13 line and is 8.2 miles long, the PSC added, noting that the route of the uprate follows the existing M13 route south from the proposed Ackley substation to the Kelly substation in the village of Weston, Marathon County.
The proposed project’s estimated cost in 2019 dollars is about $29.7 million, and of that, about $21.3 million would be for transmission line work, about $7.5 million for substation work, and $981,000 for pre-certification costs, the PSC said.
As noted in the decision, ATC in January filed its application with the PSC. Alternatives to the project have been considered, but no other reasonable alternatives to the proposed project exist that could provide adequate service in a more reliable, timely, cost-effective and environmentally acceptable manner, the PSC said.
The need for the proposed project is driven by replacements of aging facilities and the need to ensure reliable and safe operation of the transmission system in the project area, the PSC said.
Old wooden poles at the Blackbrook and Bunker Hill substations have sustained woodpecker damage and will require replacement in the next five to 10 years. The PSC further noted that equipment at the Blackbrook substation including bus supports and disconnect switches, and motor operators at the Bunker Hill substation will require replacement due to age and condition.
The proposed project will not have undue adverse impacts on environmental values, including ecological balance, public health and welfare, historic sites, geological formations, aesthetics and recreational use, the PSC said.
The proposed project will affect state highways and will require permits from the state Department of Transportation, the PSC said, adding that the proposed project will affect waterways and wetlands, and will require permits from the state Department of Natural Resources for construction in waterways and wetlands, construction site erosion control, and storm water handling.
The PSC also said that the proposed project will require ATC to obtain permits from, provide notifications to, and coordinate with the U.S. Army Corps of Engineers.
Discussing the environmental review, the PSC said that the existing line on the uprate section of the project passes near many homes in the village of Weston. About 230 homes lie within 300 feet of the centerline in that area, and of those, about 80 are within 100 feet of the centerline. The PSC also said that the line passes through a mobile home park where three mobile homes may need to be relocated.
For the entire project, 79 structures would be built in wetlands, the PSC said, adding that 16.9 acres of scrub shrub wetlands and 21.8 acres of forested wetland would be permanently converted to herbaceous wetlands. ATC would be required by DNR to provide compensatory mitigation for the unavoidable wetland impacts, including permanent fill in wetlands, temporary impacts due to construction access, and conversion of wooded wetlands.
Off-right of way (ROW) access paths will be needed for project construction, and ATC stated in its application that those access routes will be based on field review of the approved route, negotiations with local landowners, and/or contractor requirements. ATC indicated that it supports working with landowners to the extent practicable regarding the placement of facilities on their properties, the PSC added. ATC also indicated that it supports working with landowners, to the extent practicable, regarding facilities placement to minimize the effects on properties.
Noting that off-ROW access routes can potentially reduce construction impacts on wetlands and waterways, the PSC said that the DNR supports the use of such routes to avoid impacts. ATC said that at all stages of the project planning process, it has attempted to avoid impacts to wetlands and waterways and that it will continue to make decisions that avoid and minimize those types of impacts throughout construction.
The company also said that it supports working with property owners to take advantage of access that further reduces potential impacts to waterways and wetlands to the extent practicable, provided that the landowner voluntarily grants access opportunities to ATC. The PSC added that it finds that approach to be reasonable and therefore requires that ATC take the actions identified, to the extent practicable.
Among other things, the PSC said that should the scope, design or location of the project change significantly, or if it is discovered or identified that the project cost may exceed the estimated cost by more than 10 percent, ATC is to promptly notify the PSC as soon as it becomes aware of the possible change or cost increase.
ATC is to work with property owners to take advantage of access opportunities that further reduce potential impacts to waterways, wetlands, and farmland to the extent practicable, provided that the landowner voluntarily grants access to ATC, the PSC said.
In addition, ATC is to use appropriate landscaping at the Ackley substation site to screen the new facilities from the nearest home. The PSC also said that when building the proposed project, ATC is to implement all construction and environmental mitigation methods included in the project application and those recommended by DNR staff during the project review process, unless specifically modified by a subsequent DNR permit.
In addition, the PSC said that beginning with the quarter ending Sept. 30, and within 30 days of the end of each quarter thereafter and continuing until the facilities are fully operational, ATC is to submit quarterly progress reports to the PSC that include major construction and environmental milestones.