Why corrosion might take down Energy East

Barely a month after hearings in South Dakota revealed pipeline corrosion problems for TransCanada's Keystone XL pipeline, Canadian groups are warning that the same problem could happen for the company's proposed Energy East pipeline.

TransCanada's Energy East is a massive, continent-spanning 4,200-km pipeline proposal that would carry 1.1 million barrels of crude from Alberta's oil sands to the Atlantic coast every day. Critics worry about the environmental impacts of pipeline building and oil spills along the route, while proponents say it would bring 10,000 jobs to Canadians and generate billions of dollars in revenue for the six provinces it goes through.

When corrosion causes problems

In the early morning of July 29, 1995, hell fire broke loose three kilometres southeast of Rapid City Manitoba.

A pre-existing stress corrosion crack gave away, rupturing TransCanada Limited’s 42-inch natural gas pipeline. It went up with a loud explosion and then caught fire. The fire spread through the compressor station, destroying the communications system, making it difficult to shut off the flow of gas. From the mainline, the fire spread to a secondary gas line, weakening it. The second line ruptured and also went up in flames.

The fires lasted for two hours. An on-duty TransCanada staff member discovered the rupture and made two attempts to contact the regional operations controller. A third attempt from an emergency phone located outside the compressor station failed as well. Ultimately, the employee had to use a bystander’s cell phone to make the call.

A subsequent Transportation Safety Board investigation found that the supervisory control and data acquisition system malfunctioned, delaying the shut-down and the isolation of the two burning pipelines.

The line that suffered the corrosion and ruptured is part of the same line that TransCanada wants to convert and use to carry crude oil for the proposed Energy East project.

It throws into sharp relief a current argument over the reliability of the lines to withstand corrosion and safely transport a million barrels daily of Alberta tar sands crude and highly volatile Bakken crude.

Energy East protesters maintain the line isn’t safe and will ultimately result in a major oil spill, releasing potentially as much as 30 million litres of diluted bitumen into the ground.

For its part, TransCanada asserts that the pipelines are rigorously monitored, state-of-the-art and safe.

Half the ruptures were the result of stress corrosion and cracking

Mark Calzavara, the Council of Canadians’ regional organizer for Ontario and Quebec, frets that a worst-case scenario could take place with a pipeline rupture at the bottom of a river valley with a long upward slope on both sides.

“That’s where you get your worst-case scenario of a maximum leak approaching 30-million litres. That’s absolutely a worst-case scenario,’ Calzavara stresses. “But it’s a possibility.”

In the first week of September, the council released a briefing paper in which it noted that nearly half of the ruptures along the mainline were the result of stress corrosion and cracking, external corrosion and coating and welding failures.

And in 2013, the Alberta Energy Regulator flagged external corrosion as the second leading cause of pipeline failures at 12.7 per cent, largely from either age or excessive production temperatures.

In another briefing document, the Council notes that the mainline pipeline – that TransCanada would employ in Energy East – has had nine events since 1991. “Despite TransCanada’s claims of strict spill monitoring controls, almost all of the spills were discovered by people, not fancy electronic monitoring systems, and most were caused by stress, corrosion and cracking.”

Over time integrity issues will become more common as pipelines age

While TransCanada likes to show images of gleaming silver pipeline on its website, the reality is much different. A confidential 2013 report into corrosion anomalies – as the industry refers to pits, cracks, and other defects – shows a scarred, pitted pipeline.

In this instance, TransCanada caught the pipeline, reportedly built in 2009, before it ruptured. A rupture could have been disastrous: the badly corroded parts of the pipeline included one section 200 feet from the Mississippi River, while another section was a couple hundred feet from a creek that flowed directly into the river.

A 2011 paper from the National Petroleum Council in the U.S. observed that over time integrity issues will become more common as the pipelines age and cited external corrosion as one of the leading challenges.

The same paper also noted that “pipelines operating outside of their design parameters such as those carrying commodities for which they were not initially designed, or high flow pipelines are at the greatest risk of integrity issues in the future due to the nature of their operation.”

The latter describes Energy East, which will carry crude through re-purposed gas lines and which will carry some 40 different kinds of crude using a technology called turbulent flow.

The technology will let TransCanada move different batches of oil down the line, allowing customers to extract their particular crude out at points, while the rest continues to other destinations.

An explosion left a large crater after stress corrosion cracking weakened the pipeline

Tim Duboyce, TransCanada spokesman, said if the company is leaving a piece of pipeline in service, it’s because it’s been tested and monitored and that based on TransCanada’s own technical expertise, best practices and “norms in place according to federal law, that pipeline is still suitable to operate.”

Duboyce said the company uses a number of different measures to alert it if problems crop up. “If something starts to deteriorate and it gets detected, we fix it. I think when you look at our safety record, that’s working.”

According to Duboyce the company has not had an “integrity” leak - jargon for a rupture - on an oil pipeline since it got into the business of transporting oil.

A report from the Polaris Institute from June 2015 disputes that. Using TransCanada’s own data, the report asserts that the company spilled 441.7 barrels of oil in 152 spills between 2010 and 2013 in the U.S. and Canada.

As well, the ruptures have occurred on a number of its gas lines, including on the mainline that TransCanada intends to convert to carry Energy East oil.

They included an explosion in near Beardmore Northern, Ontario in 2011 that left a large crater after stress corrosion cracking weakened the pipeline; and a 2009 explosion, also from stress corrosion cracking, that left a 20-metre crater and a fire that took two days to extinguish.

In northern Alberta in 2009, another rupture from deep external corrosion sent 50-metre flames into the air and destroyed a two-hectare wooded area near the Dene Tha’ First Nation of Chateh.

A National Energy Board report cited corrosion as the cause of six other ruptures and 16 leaks on the same pipeline before 2009.