The U.S. Pipeline and Hazardous Materials Safety Administration said the Canadian pipeline company paid the full penalty amount for a release from a section of the Lakehead system in Michigan, the Detroit Free Press reports.
The rupture released about 20,000 barrels of oil into southern Michigan waters starting July 26, 2010. The National Transportation Safety Board said the rupture on the pipeline measured about 6 feet by 4.5 inches at its widest point.
Federal investigators said Enbridge overruled an analysis in 2005 that would've required excavation of the pipeline, suggesting the company knew of defects on the system by then.
Enbridge, in a statement, had said it took full responsibility for the incident, adding NTSB findings "are generally consistent" with an internal probe.
The company aims to replace hundreds of miles of Line 6B under a $268 million plan that would upgrade the pipeline's safety features and increase its volume to 500,000 barrels of oil per day.