FBI investigates fires at Enbridge Line 5 drill site and Superior office in Wisconsin

FBI leads multi-agency probe into Ashland County and Superior fires

The Federal Bureau of Investigation is leading a probe into two fires last week at Enbridge sites in northern Wisconsin, according to FBI public affairs officer Caroline Clancy. "The FBI, along with our local, state, and federal partners, are investigating the cause of the fires in Superior and Ashland, Wisconsin," Clancy said, adding the agency had no additional information to provide. The Bureau of Alcohol, Tobacco, Firearms and Explosives is among the agencies investigating the Ashland County fire, with ATF public affairs specialist Ashlee Sherrill saying ATF is "specifically working on the origin and cause determination as well as other matters." Wisconsin's Division of Criminal Investigations and State Fire Marshal's Office are also supporting the probe, and Ashland County Chief Deputy Dave Dawson said his office could not comment while the investigation is ongoing.

Drilling equipment and Superior office targeted in September blazes

On Sept. 17, the Ashland County Sheriff's Office and Ashland Fire Department responded to a fire involving an equipment trailer and two boring machines in the town of Gingles at a drill site for Enbridge's Line 5 reroute. No injuries were reported, and the cause remained under investigation as of the FBI's confirmation. A separate fire occurred on Sept. 14 at Enbridge's Great Lakes office in Superior, which was being sold to the private school Superior Learning Academy. Enbridge spokesperson Juli Kellner said the company supports "everyone's rights to legally and peacefully express their views about energy use" but called the incidents "neither legal nor peaceful," adding that "illegal and unsafe acts by criminal saboteurs endanger themselves, the local community, first responders and our workers." Enbridge declined to provide an estimate of damages.

Fires follow Aug. 25 gas leak on Line 5 in Iron County

The fires came weeks after an Aug. 25 gas leak on Line 5 in the Iron County town of Saxon, where Enbridge has said an unoccupied flatbed truck rolled into an open construction trench and struck the pipeline, releasing 1.3 million gallons of natural gas liquids into the atmosphere. Federal data cited by Wisconsin Public Radio identifies the release as the largest oil and gas pipeline spill involving the company and the state in more than 50 years. Line 5 carries up to 23 million gallons of crude oil and natural gas liquids daily from Superior to Sarnia, Ontario, serving 10 refineries and propane facilities in the Midwest and Great Lakes region.

Bypass restoration and unresolved regulatory dispute

Enbridge restored service to Line 5 over the weekend of Sept. 12 after constructing a temporary bypass, drawing objections from Wisconsin environmental regulators. The Wisconsin Department of Natural Resources had asked the company to halt work, saying it lacked state approvals. The status of those state approvals and any further regulatory action tied to the bypass construction was not detailed in the available reporting.

Open investigative and prosecutorial questions

The FBI, ATF, state and local agencies have not publicly identified suspects or announced charges in connection with either fire. Enbridge said it "will seek the prosecution of those individuals involved to the fullest extent of the law," but no court filings or indictments were referenced in the reporting. The Wisconsin Department of Justice referred questions to local authorities. The published accounts do not include a stated timeline for releasing further findings from the origin-and-cause investigation.