Contaminated soil removed from spill site on Enbridge’s Line 5 in northern Wisconsin

The scent of natural gas hung heavy over the town of Saxon last month, a stark reminder of the 1.3 million gallons released into the atmosphere when a subcontractor’s truck rolled into an open trench on Enbridge’s Line 5 pipeline. While immediate air quality concerns have subsided, the incident, and the ongoing remediation efforts, highlight the complexities and potential environmental risks associated with this significant infrastructure project traversing northern Wisconsin. The leak, which occurred August 25th during construction of a new 41-mile segment around the Bad River Band of Lake Superior Chippewa’s reservation, represents the state’s largest oil and gas pipeline spill in over 50 years, according to federal data.

What Happened

The incident occurred when an unoccupied flatbed truck, belonging to a subcontractor working on the Line 5 reroute, rolled into an open trench impacting the pipeline. This resulted in the release of over 1.3 million gallons of natural gas liquids into the air. The rerouting project aims to move the pipeline around the Bad River Band’s reservation, a process that has been underway for some time. Enbridge spokesperson Juli Kellner stated that environmental monitoring remains ongoing, though no groundwater impacts have yet been detected. The company is currently sampling and excavating soil to remove contaminated material, a process overseen by the Wisconsin Department of Natural Resources (DNR).

According to a report submitted by GEI Consultants on behalf of Enbridge, initial sampling has shown no impacts to surface water, private wells, or groundwater outside the immediate site perimeter. However, approximately 4,275 tons of contaminated soil and debris have already been removed and disposed of at Waste Management’s Timberline Trail Landfill in Weyerhaeuser, while roughly 4,500 gallons of water mixed with firefighting foam (excluding PFAS) were sent to the Reworld Fox Valley/Oshkosh Material Processing Facility in Winneconne. The contamination detected includes volatile organic compounds (VOCs) and polycyclic aromatic hydrocarbons (PAHs) linked to petroleum products, and initial testing revealed benzene levels exceeding state residual contaminant levels intended to protect groundwater. A temporary monitoring well also exceeded groundwater standards for benzene, prompting further action from Enbridge.

Christine Sieger, remediation and redevelopment director with the Wisconsin DNR, emphasized that the excavation process is ongoing and that a full site investigation will be required once the immediate remediation is complete. This investigation will examine groundwater, surface water, and sediment to understand the full extent of the contamination’s movement. Enbridge has submitted plans to backfill the site with crushed rock topped with soil, a process that is currently under review with input being sought from 11 federally recognized tribes in Wisconsin, along with the Brothertown Indian Nation and Great Lakes Indian Fish and Wildlife Commission. The DNR hopes to see backfilling completed by the end of the year. Wisconsin Department of Natural Resources

Community Reaction

While Enbridge maintains it is addressing concerns related to the Line 5 project, the incident has understandably raised questions and anxieties among residents and tribal communities. The release of such a significant volume of natural gas liquids into the atmosphere poses immediate health risks, and the long-term implications for groundwater contamination are a serious concern for those who rely on these resources. The incident underscores the importance of rigorous safety protocols and environmental safeguards when undertaking large-scale infrastructure projects, particularly those impacting sensitive ecosystems and communities.

DNR Enforcement Actions

The DNR has already taken action, issuing a notice of violation against Enbridge for alleged violations of state environmental laws. This includes the spill itself and the construction of a temporary bypass in September without proper state approvals. An enforcement conference was initially scheduled for October 26th, although the DNR is currently considering options for enforcement. Enbridge insists it takes these concerns seriously, stating that all violations have been mitigated or are in the process of being addressed. The company is also working to meet terms of a corrective action order issued by the federal Pipeline and Hazardous Materials Safety Administration. Environmental Protection Agency

What’s Next

The immediate focus remains on the ongoing soil excavation and remediation efforts, with Enbridge working to contain and remove contaminated material. Simultaneously, investigations are underway to assess the full extent of the groundwater impact, particularly concerning a potential aquifer breach near the Marengo River. Three monitoring wells have been installed along the pipeline’s route to help determine the source of the release, although it remains unknown if an aquifer breach occurred. The DNR is actively seeking input from tribal nations to ensure that remediation plans adequately protect sensitive resources and tribal interests. Federal Bureau of Investigation

Katherine's Take

This incident with Enbridge’s Line 5 serves as a stark reminder of the inherent risks associated with large-scale infrastructure projects and the importance of prioritizing safety and environmental stewardship. While the company is taking steps to address the immediate contamination, the potential for long-term groundwater impacts remains a significant concern for families and communities who depend on these vital resources. The fact that this occurred during construction, while rerouting the pipeline to avoid impacting tribal lands, highlights the complexities of balancing economic development with environmental protection and respecting the rights of indigenous communities. It’s crucial that the DNR continues to hold Enbridge accountable for its actions and that ongoing monitoring efforts are transparent and accessible to the public. Beyond this specific incident, it prompts a larger conversation about the safety and resilience of our nation’s energy infrastructure, and the need for robust oversight and preventative measures to protect our communities and environment. The stability of families and communities often depends on the security of their water supply—it’s a foundational need.

Project Details and Timeline

Line 5 carries up to 23 million gallons of oil daily from Superior to Sarnia, Ontario. The project to reroute the pipeline is now approximately 90 percent complete and employs over 600 workers. Enbridge anticipates the project will be fully completed in the first few months of next year. The company has also been addressing concerns related to a separate fire that destroyed a drill rig on the Line 5 project, and an FBI probe is underway regarding that incident. Enbridge Energy

Resources

Residents concerned about the Line 5 project and its potential impacts can find more information and submit comments through the following resources:

• Wisconsin Department of Natural Resources: Information on environmental regulations, permitting, and enforcement actions.
• Environmental Protection Agency: Federal regulations and resources related to environmental protection.
• Enbridge Energy: Project information and updates from the company.
• Federal Bureau of Investigation: Information on the ongoing investigation into the drill rig fire.
• City of Superior, Wisconsin: Local government resources and information.
• Weyerhaeuser: Information about the Timberline Trail Landfill.
• Reworld Fox Valley/Oshkosh Material Processing Facility: Information about the facility where firefighting foam was disposed of.
• Bad River Band of Lake Superior Chippewa: Information about the tribal nation impacted by the pipeline reroute.
• Great Lakes Indian Fish and Wildlife Commission: Information about the commission involved in the review process.
• Brothertown Indian Nation: Information about the nation involved in the review process.

The situation with the Line 5 pipeline underscores the ongoing challenges of balancing energy infrastructure needs with environmental protection and community well-being. It’s a responsibility that demands transparency, accountability, and a commitment to safeguarding the resources that sustain us all.

As the remediation process continues and the Line 5 project nears completion, it is imperative that residents remain informed and engaged. The long-term health of our communities and environment depends on it.