A crude oil pipeline operator’s pervasive organizational failures combined with weak federal regulations to cause a massive 2010 spill in Michigan, the National Transportation Safety Board said. Its investigation found that multiple small corrosion fatigue cracks grew in size and linked together, causing a breach more than 80 in. long in Enbridge Energy Partners LP’s line near Marshall, Mich., on July 25, 2010.
NTSB said it identified a complete safety breakdown resulting in the discharge of more than 840,000 gal of crude into Talmadge Creek and the nearby Kalamazoo River for 17 hr until a local utility worker discovered the spill and notified Enbridge.
“Their employees performed like Keystone Kops and failed to recognize their pipeline had ruptured and continued to pump crude into the environment,” NTSB Chairwoman Deborah A.P. Hersman said. “Despite multiple alarms and a loss of pressure in the pipeline, they failed to follow their own shutdown procedures through three shifts.”
The board’s draft finding came after the US Pipeline and Hazardous Materials Safety Administration proposed a record $3.7 million fine and 24 enforcement actions against Enbridge on July 2 in connection with the incident.
NTSB said Enbridge’s Line 6B had been scheduled for a routine shutdown at the time to accommodate changing delivery schedules. Following the shutdown, operators in Enbridge’s control room in Edmonton received multiple alarms indicating a problem with low pressure in the pipeline, which were dismissed as being caused by factors other than a rupture. NTSB cited this as evidence of “inadequate training of control center personnel.”
NTSB also found that Enbridge failed to assess the pipeline’s structural integrity, including correctly analyzing cracks that needed to be repaired. NTSB characterized the control room, leak detection, and environmental response as deficient, and described the event as an “organizational accident.”
The board also found PHMSA’s regulations regarding pipeline assessment and repair criteria at the time were weak, and said a cursory review of Enbridge’s spill response plan contributed to the accident’s magnitude. Its investigation found that Enbridge’s detected the cracks in Line 6B which ultimately ruptured in 2005 and did not repair them. A further examination of records found that the pipeline operator’s crack assessment process was inadequate, it said.
“Enbridge knew for years that this section of the pipeline was vulnerable, yet [it] didn't act on that information,” Hersman said. “Likewise, for the regulator to delegate too much authority to the regulated to assess their own system risks and correct them is tantamount to the fox guarding the hen house. Regulators need regulations and practices with teeth, and the resources to enable them to take corrective action before a spill, not just after.”
As a result of its investigation, NTSB reiterated one recommendation to PHMSA and issued 17 new safety recommendations to the US Department of Transportation, PHMSA, Enbridge, the American Petroleum Institute, the International Association of Fire Chiefs, and the National Emergency Number Association.
Two industry associations welcomed the findings. “Liquid pipeline operators want to learn more about what happened, review the NTSB report, and begin sharing lessons to continue improvements in pipeline safety,” said Andrew J. Black, president of the Association of Oil Pipe Lines.
American Petroleum Institute Pipeline Director Peter Lidiak, in a separate statement, added, “A number of industry safety enhancement initiatives are under way that include improving recognition of, response to and reporting of large ruptures; accelerated research and development to improve in-line inspection tools, or smart pigs; and better ways to share industry learning from incidents, like the Marshall release.”
But Carl Weimer, executive director of the Pipeline Safety Trust, said NTSB’s findings make clear that some of the basic foundations of pipeline safety need to be reexamined. “While the industry through regulations has been given great flexibility to determine the safety and integrity of [its] own pipelines, it has become increasingly clear that [it] does not always handle [its] responsibilities responsibly, and that government regulators do not have the resources, data, or ability to verify that industry decisions are safe enough,” he said.
Contact Nick Snow at firstname.lastname@example.org.