The National Transportation Safety Board has approved the findings of its investigators that Canadian company Enbridge Inc.’s neglect of pipeline cracks and its slow response likely caused the most expensive onshore oil spill in U.S. history.
The board on July 10 approved its staff’s findings about the cause of a 2010 rupture near Marshall in southwestern Michigan that dumped about 843,000 gallons of heavy crude into the Kalamazoo River and an tributary creek.
Investigators say Enbridge knew five years before the rupture that cracks were forming in the pipe but didn’t perform excavations that might have prevented it.
They also say Enbridge control center personnel twice pumped more oil into the line after the spill began and didn’t discover what had happened for more than 17 hours.
The NTSB says Enbridge’s failure to deal adequately with cracks in the pipeline and its slow response to the rupture likely caused the spill near Marshall, a city 95 miles west of Detroit.
The pipeline runs from Griffith, Ind., to Sarnia, Ontario.
Enbridge Inc. says it has improved its operations and training after the spill. It says it also plans to see whether further improvements were needed.
Stephen Wuori is the company’s president for liquids pipelines and says “safety has always been core” to Enbridge’s operations. He says Enbridge wants to learn from what happened to ensure it’s not repeated.
The NTSB report recommended that:
- U.S. Department of Transportation audit the Pipeline and Hazardous Materials Safety Administration’s onshore pipeline program, fix problems and provide more resources.
- The administration toughen regulations dealing with how companies monitor pipelines for cracking, including criteria for determining when lines must be excavated for visual inspections.
- The administration develop requirements for training pipeline control center staff.
- Enbridge improve its pipeline integrity policies, staff training and emergency response plans.
- Enbridge train local first responders about dealing with pipeline spills, including use of oil containment devices.