Damaged track switch derailed sulfur-hauling train in Whatcom County

Federal officials say a damaged track switch knocked a train carrying hazardous materials off the rails in Whatcom County last week.

Three tank cars carrying diesel fuel and two carrying molten sulfur tipped over along the BNSF Railway tracks in the tiny trackside town of Custer. Molten sulfur is a hazardous material used in oil refining and paper milling and transported at about 290 degrees Fahrenheit.

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Six cars in total ran off the rails just before 11 p.m. on June 4, according to an email from BNSF spokesperson Lena Kent. The Washington Department of Ecology, which sent a responder to the crash site, said five cars derailed.

No spills or injuries were reported.

The train derailed where two tracks converged, according to Federal Railroad Administration spokesperson Warren Flatau. The track switch there had been damaged by the previous train running through it when it was not aligned properly.

That maneuver, known as "running through a switch," left the switch “gapped,” or in between alignments, when the 26-car mixed-freight train, heading the opposite direction, then hit it and derailed late on June 4.

Such switch problems are common enough that the railroad agency conducted a special investigation of them in 2019. They are usually caused by human error, such as a worker forgetting to align a switch, and rarely just one error at a time, according to the rail agency.

"Railroads must address multiple factors to reduce [run-through switch] events," the Federal Railroad Administration concluded after studying one passenger railroad with an exceptional number of run-through switches.

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The Custer train derailed less than a mile from where an apparently sabotaged oil train — its brakes and couplings disabled — pulled apart and crashed into itself, bursting into flames, in 2020.

BNSF is investigating the incident and has until July 31 to submit its crash report to the agency.

Flatau with the Federal Railroad Administration said he did not know the train’s origin or destination and that the railroad administration is not conducting a formal investigation of the incident. With no injuries or spilled hazardous materials and less than $1 million in track and equipment damage, the derailment does not meet the agency’s threshold for opening investigations.

Kent with BNSF Railway did not respond to KUOW’s questions on the train’s destination and origin.