Accident occurred on existing Line 5 pipeline where a bypass valve is being added to connect to $1-billion pipeline under construction
Canadian energy firm Enbridge has shut down part of its Line 5 pipeline in Wisconsin as it works to stabilize the site of a line strike near Saxon, Wis., that happened Aug. 25 when an unoccupied, parked semi truck rolled into an excavation site and hit a valve.
The accident occurred at about 10 a.m. on the Line 5 valve project resulting in the release of natural gas liquids (NGLs), according to the Iron County Sheriff’s Office. Two nearby homes in the rural area were evacuated. No injuries were reported.
The cause of the accident is under investigation.
“I don’t know if it was operator error or equipment error,” said Stacy Ofstad, emergency management director for Iron County on Aug. 27. “Right now, [the semi truck is] sitting in a pool of natural gas.”
The existing pipeline, which has shut-off valves situated at intervals along its length, was shut down for a ten-mile zone in the area of the accident.
Ofstad said “initially the natural gas was a plume that’s highly volatile. Now it’s in gas form and it’s still volatile but there is extensive air monitoring going on for safety of residents outside of the perimeter.”
NGLs are hydrocarbons—including ethane, propane, butane, isobutane and natural gasoline—that are separated from natural gas during processing. They are used as fuels and as feedstocks in the production of plastics, medical supplies, electronics, clothing, fertilizers and other products.
Ofstad said the accident occurred on the far east side of the existing Line 5 pipeline where Enbridge is adding a bypass valve to connect the existing pipeline to a new pipeline that’s being built.
Ongoing Disputes Over Pipeline Projects
Enbridge is building a $1-billion, 41-mile stretch of pipeline to avoid tribal lands in Wisconsin, while still operating a disputed 12-mile pipeline segment on reservation land owned by the Bad River Band of Lake Superior Chippewa, which is currently in legal proceedings to have it removed. The pipeline is part of a network that brings oil and gas to the U.S. from Canada.
The U.S. Army Corps of Engineers issued a permit Aug. 12 to Enbridge for construction of another part of the Line 5 pipeline that would be enclosed in a four-mile-long tunnel along the bottom of the Straits of Mackinac in Michigan to fully enclose twin oil and gas pipelines.
David Holtz, campaign coordinator for Oil & Water Don’t Mix, which opposes the Michigan project, said in a statement that he has safety concerns about both projects.
“This is the project that Enbridge has claimed it can build safely around sensitive waters, and the reroute meant to move Line 5 off the Bad River Reservation. But it didn’t survive its own construction phase without a breach and an evacuation order.”
Enbridge did not immediately respond to a request for comment.
