Union Pacific investigating cause of explosive train derailment

Images and Tweets courtesy FOX2Now St. Louis

Story includes updates

Union Pacific (NYSE: UNP) is investigating why a train carrying flammable liquid derailed and caught fire at UNP’s rail yard in Dupo, Illinois, on Sept. 10. Dupo is across the Mississippi River from St. Louis, Missouri.

A preliminary review of the accident indicates that train handling might have played a role in the derailment, according to UNP spokesperson Kristen South. UNP is undertaking a detailed investigation and it will give its results to the Federal Railroad Administration.

The track reopened early on Sept. 11 following the replacement of some ties, rail and ballast, which is the rock that stabilizes the flat bed.

UNP said environmental contractor CTEH concluded air quality monitoring at 8 a.m. local time on Sept. 11 and determined after repeated tests that there wasn’t a public health concern. The railroad’s hazmat personnel meanwhile is remaining on the scene to address residual environmental impacts, such as testing soil and cleaning ditches. 

The derailment occurred on Sept. 10 at around 12:45 p.m. local time at UNP’s Dupo Yard near Carondelet Avenue between Main and Adams Road.

UNP was building the train so that it could depart. It was then that the train derailed, causing a tank car to catch fire. The tank car was reported as carrying a flammable liquid called methyl isobutyl ketone, which is typically used as a solvent for paints, varnishes and lacquers.

UNP worked with area first responders to put out the fire. No injuries were reported at the time, and the yard and the nearby intermodal ramp were evacuated.


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Joanna Marsh

Joanna is a Washington, DC-based writer covering the freight railroad industry. She has worked for Argus Media as a contributing reporter for Argus Rail Business and as a market reporter for Argus Coal Daily.