Enbridge fixes aquifer breached during Line 3 construction

Enbridge has stopped the flow of water from an aquifer that its workers breached a year ago during construction of the Line 3 oil pipeline in northern Minnesota, a Minnesota Department of Natural Resources spokesperson told the Reformer Thursday.  

The DNR fined Enbridge $3.3 million in September and ordered the company to repair the puncture, alleging the breach was a violation of state law. The DNR is also looking into two other potential aquifer breaches but has declined to share any information, citing ongoing investigations.

Line 3 opponents say the repair efforts were too little, too late. The Minnesota attorney general is looking into the case for potential criminal charges, the Reformer has learned.

“There’s no doubt they’re taking a lot of money and a lot of effort to (fix the breach),” said Jeffrey Broberg, a retired geologist who has been tracking the breach with Line 3 opponents. “But (Enbridge) should have been required to fix this before they proceeded with the pipeline.”

Enbridge didn’t notify the DNR about the breach, according to the agency, which happened when workers deviated from construction plans that called for digging a trench up to 10 feet deep at the site. Instead, they dug a trench 18 feet deep and installed metal sheets for trench support as deep as 28 feet, piercing the aquifer, the DNR says.

Water from the aquifer flowed to the surface, filling the trench, according to the DNR. Over the next few months, independent environmental monitors at the site continued to notice more water flow than expected. But the monitors enforce permit requirements — not construction plans — so they didn’t identify that Enbridge’s failure to follow construction plans led to an aquifer breach, according to the DNR.

The DNR found out about the issue in June and ordered Enbridge to temporarily halt construction, the agency says. Aquifer ruptures can lower groundwater levels, which can harm rivers and lakes. Minnesota state officials were especially concerned that low groundwater levels could damage a rare wetland near the breach.

News of the rupture became public in September, when the DNR issued a civil enforcement order requiring Enbridge to pay for additional monitoring and restoration of the nearby wetland, and to stop the flow of groundwater in 30 days — which is no easy feat. Stopping uncontrolled flow from a pierced aquifer is a complex, expensive process that involves extensive study of the affected area, data collection and planning.

Enbridge missed the Oct. 15, 2021, cleanup deadline and agreed to pay additional fines for future groundwater losses. 

The company informed the DNR on Tuesday that it stopped the flow of groundwater from the site, said DNR spokesperson Gail Nosek.

“(The) DNR will continue to assess current conditions and monitor the aquifer breach repair for long-term effectiveness,” Nosek said. 

Broberg said based on his experience with aquifer issues during construction, he didn’t think it would be feasible to fix the breach in 30 days and wasn’t surprised Enbridge missed the deadline. Still, he feels Enbridge should face stronger repercussions for failing to comply with the DNR’s initial orders.

“They blew past their deadline — and the deadline probably wasn’t realistic in the first place — but there’s little consequence,” Broberg said. For a multi-billion-dollar-company, “a $3 million (fine) is nothing.”

Enbridge could still face criminal charges for the incident, however.

The DNR alleged the company violated a state law that prohibits appropriating “waters of the state without previously obtaining a permit from the commissioner” and referred the case to the Clearwater County Attorney. The Clearwater County Attorney referred the case to the Minnesota Attorney General’s Office, which is evaluating evidence for a charging decision and potential prosecution, a spokesperson told the Reformer.

The Minnesota Pollution Control Agency is also investigating potential Line 3 permitting violations in more than 10 spills of drilling fluid — a mix of mud and chemicals used as lubrication for drilling under rivers — at 12 river crossings during pipeline construction over the summer. 

Enbridge’s 337-mile Line 3 pipeline became operational in October 2021, following six years of permitting, review and litigation and nearly a year of construction.

Correction: An earlier version of this story misstated the status of the aquifer breach. The story has been updated to reflect that Enbridge said it stopped the flow of water on Jan. 18.