It was April of 2010 when Enbridge Line 6b ruptured, spilling more than a million gallons of Canadian heavy crude oil into a creek near Kalamazoo.
It was the largest inland spill in United States history.
That spill gave Michiganders a very good reason to sit up and pay closer attention to the nearly 3,300 miles of hazardous liquid pipelines that weave through our state, particularly Enbridge Line 5, which runs in the Straits of Mackinac.
That pipeline is making headlines again in Michigan. This time, because the pipeline's structural integrity has been questioned.
There are people who fear another pipeline leak, and there are others who think the science is not being represented properly and that the fears are overblown.
Richard Kuprewicz is the president of Accufacts Inc. His company works with pipeline companies.
Line 5 is over 60 years old now, but Kuprewicz told us the pipeline’s age isn’t a concern.
“Even steel of over 100 years ago, pipe steel does not wear out. It isn’t like an automobile engine. The real factor on pipe steel, this is a very important distinction, is what we call the vintage. Depending on how the pipe was made and what its specifications were and the various processes to make the pipe, there can be various different types of threats,” he said.
He told us that even brand new steel, if not “respected appropriately,” can fail faster than 100-year-old pipelines.
According to Kuprewicz, corrosion is “a leading, if not the major cause” of failure in liquid transmission pipelines like the Line 5.
“There are some people who will say third party damage is the leading cause of pipeline failure, but for liquid transmission pipelines in the United States, we don’t think that’s an accurate statement.”
He told us that considerable advancements have been made in the fight against internal and external corrosion over the past several decades, but corrosion still tends to be the leading cause of pipeline failures.
The Line 6b failure was caused by two specific types of corrosion, he said, that both thinned and cracked the pipe walls.
“It got to a certain thickness of pipe steel from these two types of corrosion and went to failure at a very low operating pressure,” he said.
Kuprewicz told us that in over four decades of investigation, he’s never seen a single-event failure. It’s always “a whole series of failure,” and the 6b was no different.
“If you were to look and read in detail the public [National Transportation Safety Board] report, you’re going to find there were failures on many levels, on many fronts, in many areas of that operation,” he said.
“I’m not here to belittle or badger the operator ... it’s just, when you read the report, it’s just downright embarrassing. And that’s not a place I want a pipeline company to be at.”
Kuprewicz admitted it can be difficult for the public to get a sense of when a pipeline operator is doing things the way they should, but said there are signs to look for.
“I would suggest that people look for consistency and … truthiness,” he said. “Respect that they cannot disclose everything about their pipeline, but what they do disclose ought to be factual, truthful and consistent. If they’re caught in too much PR spin, it’s hard to maintain their stories, and so you’ll see inconsistencies in some of the way they deal with problems.”
“That’s the thing I constantly warn operators about. We understand you can’t disclose everything to the public, but what you tell them, if you’ve got a good story, you should be able to tell them the truth.”
Stateside originally aired this segment on April 5, 2016.