The Minnesota Department of Natural Resources announced Thursday that Enbridge must pay $3.32 million for failure to follow environmental laws.
According to the release, Enbridge breached the confining layer of an artesian aquifer, near a calcareous fen wetland by the Clearbrook Terminal.
The breach resulted in an unauthorized groundwater appropriation during the construction of the Line 3 pipeline.
Enbridge began work on the Clearbrook Terminal site early this year.
Independent environmental monitors, working on behalf of the DNR and the Minnesota Pollution Control Agency, first observed unusual amounts of water in the trench in late January.
In mid-June, the DNR identified there was a potential breach of the aquifer’s confining layer at the Clearbrook terminal construction site.
Through Sept. 5, Enbridge’s violation resulted in an estimated release of approximately 24.2 million gallons of groundwater from the aquifer.
The DNR says this water was pumped from the trench, treated to remove sediment and released to a nearby wetland.
A calcareous fen wetland has stringent statutory protections that rely on mineral-rich groundwater to thrive.
Enbridge’s submitted plans to the DNR called for the use of traditional trench construction methods at a depth of 8-10 feet.
Instead, Enbridge constructed the trench at a depth of about 18 feet, with sheet piling installed to a depth of 28 feet.
This deviation led to the breach, resulting in an uncontrolled flow of groundwater into the trench.
Enbridge failed to notify the DNR of the groundwater situation at the Clearbrook terminal.
The $3.32 million Enbridge must pay includes $300,000 in initial mitigation funds to pay for the loss of groundwater resources, $250,000 for DNR monitoring of the calcareous fen wetlands near the aquifer breach, and a $20,000 administrative penalty, the maximum allowed under state law.
Enbridge must also place $2.75 million in escrow for restoration and mitigation of any damage to the wetland.
The DNR’s restoration order also requires Enbridge to implement numerous plans to address the damage done, and Enbridge must also fund a re-inspection of any and all areas along the entire route where construction depths deviated from the plans.
This matter is also referred to the Clearwater County Attorney’s Office for criminal prosecution, for appropriating waters of the state without obtaining a permit.