When a ruptured pipeline spilled 20,000 barrels of oil into a North Dakota wheat field last month, a state health official said it was "the best place it could've occurred" -- far from population centers and water supplies.
But what if a similar spill occurs in the worst place?
That's the concern raised in a video released by a national environmental group this month.
In the cold, fast-flowing depths of the Straits of Mackinac run pipelines which the National Wildlife Federation (NWF) says could pose a dire threat to the Great Lakes and the beloved tourist culture of nearby Mackinac Island.
And while Enbridge, which operates the pipelines, says it's taking rigorous measures to prevent such a disaster, advocates and pipeline experts say a lack of transparency coupled with the company's checkered safety record leave them unconvinced. Enbridge is the same company whose pipeline in Marshall, Michigan spilled more than 23,000 barrels of heavy tar sands oil into the Kalamazoo River in July 2010 – the largest onshore oil spill in U.S. history.
The ongoing cleanup of that spill, along with the recent North Dakota incident, have elevated worries that current regulations and industry safeguards aren't strong enough to prevent another disaster.
A 'recipe for disaster'
The twin 20-inch-diameter pipelines more than 200 feet deep below the Straits are coated in ragged algae and encrusted with mussels and sediment, as shown in the video, and long spans hover unsupported above the lake floor.
The pipelines were built in 1953 and carry oil from the western U.S. and Canada to refinery facilities in Sarnia, Ontario.
The Mackinac pipelines, part of Line 5 in the company’s Lakehead System, have never had a serious spill. But due to the sensitive location and the pipelines’ increasing age, the NWF calls them a “recipe for economic and environmental disaster” in its 2012 report Sunken Hazard.
Given the swift and fluctuating currents of the stretch separating Michigan’s Lower and Upper peninsulas not far from the Canadian border, the report says:
A large oil spill in the Straits of Mackinac could potentially spread across vast areas of Lake Michigan and Lake Huron. A far-reaching oil slick that spread into Lake Huron could also affect Georgian Bay, one of the most vibrant freshwater ecosystems on the planet.
The NWF is a member of RE-AMP, which also publishes Midwest Energy News.
In 2012 Enbridge increased the amount of oil being transported on the Mackinac pipelines, to handle increased outputs from the Bakken oil shale in North Dakota. The NWF is concerned this increase could put more stress on the pipelines.
NWF community outreach regional coordinator Beth Wallace said the group thinks a public comment period and environmental impact statement should have been required before Enbridge was allowed to increase capacity on the pipeline.
However, Enbridge spokesperson Jackie Guthrie called the increase a “relatively minor expansion” in which pumps and other facilities were upgraded but no new pipeline was added.
“The Straits crossing is regularly inspected, using both underwater autonomous vehicles (UAVs) and state-of-the-art inline inspection tools,” said Guthrie. The reports are not made public for security reasons, she said, but the company has posted photos of the pipelines online.
NWF is demanding that Enbridge provide more details about its monitoring and inspection procedures and potential cleanup plans for Line 5. The group's 2012 report notes that Enbridge’s emergency response plan says it takes a minimum of eight minutes to isolate a leak and shut down a pipeline:
“Enbridge has estimated that a ‘worst case’ discharge for line 5, with the eight minute shut off, would be up to 1.5 million gallons [about 36,000 barrels] of oil released," the report notes. "However, that is hardly worst case. Enbridge did not react to the Kalamazoo River spill for 17 hours despite warnings from their leak detection system, and instead had to be told about that release by a local utility.”
Enbridge has been under scrutiny since the Michigan spill as well as smaller but significant spills, including one in the Chicago suburb of Romeoville that affected gas prices nationwide, just weeks after the Michigan disaster.
In all, according to NWF, Enbridge’s North American pipelines have spilled almost 170,000 barrels of oil since 1999. Enbridge adopted monitoring improvements in the wake of the Michigan spill, detailed on their website, but environmental groups are still wary.
The Marshall spill shed light more generally on a federal oversight process which many legislators and industry watchdogs have found lacking, leading to Congressional scrutiny of the Pipeline and Hazardous Materials Safety Administration (PHSMA), part of the Department of Transportation.
Last week the Wall Street Journal reported that PHMSA has significantly increased its grants aimed at helping companies find flaws in their pipelines, noting that existing monitoring technology including “smart pigs” that run through pipelines often miss serious flaws.
Images raise questions
The NWF team experienced the Straits of Mackinac’s trademark strong and unpredictable winds during their dive to get the video of Line 5.
“The wind would literally change direction every few minutes,” said Wallace, meaning in the case of a spill, “the weather would hinder any kind of recovery effort. Especially in winter, they might not even get out there.”
The NWF video highlights what the group describes as “broken supports” around the pipeline – pieces of metal looking like big broken staples, and in NWF’s view, indicating evidence of corrosion that could also affect the pipeline itself.
The video also tracks lengths of “unsupported pipeline” – where the pipeline is suspended above the lake floor and could be under greater stress from the current, the weight of encrusted debris or the impact of dropping boat anchors or other foreign objects.
Guthrie said the “broken supports” are not actually supports at all, but old steel bands that had held oak protective coverings when the pipeline was constructed. She said the pipeline is anchored to the ground every 75 to 90 feet, that the sediment and mussels are not harming it and that the company periodically installs new anchors to reduce the lengths of unsupported pipeline.
The current means the bottom is constantly shifting and disappearing from below the pipeline, she said, so a robotic vehicle is used to monitor and add new supports.
Guthrie did not respond to questions about such a pipeline’s expected lifespan, but said, “If properly maintained and protected, pipelines should have extraordinarily long lives. Old age in a pipeline does not – by itself – automatically mean a pipeline segment should be replaced or is unsafe.”
Pipeline expert Richard Kuprewicz said NWF’s images don’t indicate any immediate reason for concern, especially given that the pipeline has never had a serious leak or spill. But Kuprewicz said Enbridge should be more transparent.
“If (environmentalists) were to get straight answers about these questions, they’d know it’s either under control or it’s not,” he said. “Not getting straight answers makes them extremely nervous. That’s the problem in this country, everyone uses the guise of security to avoid answering serious questions that are not actually related to security.”
He said NWF’s concerns about the increased capacity of the pipeline are valid.
“When you increase pressure it creates other complications, even if it’s been running fine for 50 years it can cause new risks,” he said. “It’s fine for NWF to say. ‘We don’t want to get into your specific details of your pipeline operation but what can you show us that answers some questions, that shows this pipeline can deal with (the increased pressure)?’”
Wallace said the NWF was also concerned by documents they obtained from PHMSA that indicated a seemingly high number of “false alarms” on Line 5 – 16 during a 30-day period in 2012, including two having to do with measures of a phenomenon called liquid-column separation.
One of the reasons Enbridge controllers were so slow in identifying the Michigan spill was that they attributed warning signals to column separation that is expected to happen during routine shutdowns like one that pipeline was undergoing. Kuprewicz said such reports "can generate way too many false alarms, training control room personnel to ignore the few times that a leak detection system is indicating a release such as a rupture.”
He said that U.S. regulations adopted in 2012 “require management to track and evaluate their control room alarms periodically and deal with them if too many are, shall we say, ‘false.’”
Kuprewicz added that “Enbridge’s control room may be in Canada, but if it operates pipelines in the U.S. those specific pipeline operations better be following U.S. federal pipeline safety regulations.”
Enbridge spokesman Larry Springer said the pipeline is monitored from the company's Edmonton control room, in compliance with all U.S. PHMSA regulations. He said false alarms should not be a concern since leaks are detected through two types of monitoring -- comparing historical and current data, and a separate leak detection system.
"Either investigation will result in an emergency shutdown and response if indications of a leak exist," Springer said. "The window for completion of these assessments is 10 minutes. If the assessments are inconclusive, the pipeline is shut down. If there are other indications of a possible leak, the pipeline will be immediately shut down."
Tar sands connection
Line 6B, the pipeline that ruptured in 2010, and other Enbridge pipelines in the Lakehead System carry oil from the Albertan tar sands in various states of refining, including the thick gooey tar sands cut with caustic chemicals known as diluted bitumen or “dilbit.”
Line 5 in the Straits of Mackinac does not carry dilbit, according to Enbridge, but “light crude oil, light synthetic crude and natural gas liquids.” The Sunken Hazard report notes that pipeline companies can change what they ship through pipelines without notifying the government or the public.
And Wallace said that while the oil Enbridge says it is shipping may not be as heavy as that which sunk to the bottom and caused a cleanup nightmare in Michigan, it is still on the heavier end of the spectrum and could be difficult to remove.
“It’s tar sands-derived oil, it’s gone through one of many upgrading processes so it’s not as heavy as the dilbit in Kalamazoo but it’s just one step up, not light by any means,” Wallace said. “A leak from this pipeline could be devastating. And unfortunately Enbridge has an operational history in the region that is very poor.”