A letter penned earlier this month by the Transportation Safety Board (TSB) recently posted to their website suggests a broken rail was the cause of a pair of derailments this winter near Guernsey, Sask.
The letter was addressed to Transport Canada and indicates that despite newer, safer train cars, maintenance standards have to be adjusted to prevent future derailments.
The letter examines seven derailments since 2015 that involved petroleum crude oil, including one from December 9 of last year and another from February 6, 2020 that took place near Guernsey. Of the seven derailments examined, six happened during the winter.
The February derailment saw a large fire and a precautionary evacuation of about 85 people from Guernsey. A post-accident examination suggested that 27 of the cars leaked oil. No mechanical defects were found on the train or its cars.
The two Guernsey derailments resulted in a total of 3.1 million litres of crude oil released and took place when the temperature hovered around the -20 C mark.
The cause of both is listed as “suspected broken rail.”
The TSB said both involved key trains as well as key routes. Key trains include dangerous goods, while key routes are tracks that carry 10,000 or more loaded tank cars or intermodal portable tanks containing dangerous goods.
“Over the past ten years or so … advancements have facilitated more effective management of in-train forces allowing for longer, heavier trains,” The TSB wrote. At the same time, there has been an increase in dangerous goods transported by rail.
Yet current inspection and maintenance standards haven’t been adjusted since 2012, TSB found. The key route designation was established in 2016. That means the 2012 guidelines don’t address the need for enhanced track standards for key routes, TSB wrote, “despite sometimes significant increases in (dangerous goods) traffic volumes.”
“Maintaining track to the .. minimum standards on key routes may not be adequate to protect against derailments,” TSB concluded.
TSB recommended that Transport Canada revise the rules to include enhanced standards for key routes.
In 2015, two investigations involved the release of large volumes of crude oil. In both cases, the cause of the derailment was either broken joint bars or a broken rail.
The TSB found that maintenance standards at the time did not anticipate the need for increased maintenance in light of increases in volume, traffic and weight.
After those 2015 derailments, CN made a significant investment in the track involved, improving its inspection and maintenance.
There hasn’t been a significant derailment on that stretch since.
TSB said the Guernsey derailments occurred with trains travelling a permitted speed using the “best tank cars available.”
Still, about 1.6 million litres of oil was released.
“This suggests that the recent tank car design improvements are alone are insufficient to fully mitigate the risk of adverse consequences” from dangerous goods derailments, the letter said.
In response, Transport Canada issued orders earlier this month slowing train speeds and mandating that railway companies address the management of their track maintenance and inspection and update the current industry rules involving track safety.
The new inspection and maintenance plans are due on Sept. 1 and need to be filed each year.