Failed fitting caused 190,000-litre oil spill at Trans Mountain site
A Transportation Safety Board report says the failure of a fitting on a section of narrow tubing at a Trans Mountain pumping station in B.C. caused a crude-oil spill last year.
The investigation report into the spill on June 12 at the Trans Mountain Sumas pump station in Abbotsford confirms as much as 190,000 litres of crude, roughly 1,200 barrels, leaked when the fitting separated on the oneinch tube. A board report released Tuesday says tests show the compression fitting wasn't properly tightened when it was installed in 2015 on a tube that carries a small amount of oil to a section of the pump station for analysis.
The pipeline was shut down within an hour of the spill from Trans Mountain's control centre in Edmonton, but the report says it took another four hours to find and manually close valves to the tube, spilling oil into a culvert, the water table and a neighbouring agricultural field.
No one was hurt and no evacuation was ordered, but the safety board report says a “multi-year remediation plan” will be needed to recover contaminants. Trans Mountain's post-spill improvements include remotely operated closure valves and a lined containment area around the aboveground tubes, along with development of a system to check the condition of existing tubing systems.
A safety message at the end of the report says it's “important” that pipeline companies inspect tubing systems to ensure proper installation.
“In the event of an unplanned product release, it is essential that station and isolation systems be properly configured to minimize the quantity of the release.”
It also says secondary containment systems, such as the oil-water separator that was overwhelmed at the Sumas pump station, “must have a means of isolation in order to prevent any off-site migration of the released product.”