Federal safety investigators say a devastating train crash in North Dakota two years ago serves as another stark reminder of why transportation officials have spent decades pushing the railroad industry to retire dangerous tank cars that break apart too easily during accidents.
The National Transportation Safety Board released its final investigation report Thursday, concluding that the standard DOT-111 tank cars are desperately in need of replacement due to how they amplify disaster when trains carrying dangerous chemicals derail, particularly when those materials ignite as occurred near Bordulac, North Dakota.
Some of the most catastrophic railroad accidents in recent years have been worsened by leaking tank cars carrying hazardous substances that ignited, including the 2023 East Palestine, Ohio, disaster and the 2013 Lac Megantic accident that destroyed much of that Canadian community and resulted in 47 deaths. The problematic DOT-111 cars were also factors in multiple devastating crude oil and ethanol crashes during the early 2000s when rail companies frequently transported entire trains loaded with these combustible materials.
Even some improved tank car designs created following earlier accidents dating to the 1990s remain inadequate because they feature thin exterior walls. More robust modern rail tank cars have better resistance to breaking open during derailments.
Additionally, railroad companies must modify how they organize their train consists to prevent flammable liquids from being positioned near chemicals that pose inhalation hazards. When this CPKC train went off the rails on July 5, 2024, methanol poured from five damaged tank cars and ignited. The resulting blaze then caused three cars containing anhydrous ammonia to rupture.
While the actual derailment resulted from a culvert failure beneath the train that broke the rail, NTSB investigators determined that the rupture-prone tank cars dramatically worsened the consequences. The safety board found that although the culvert received regular inspections, those examinations lacked the depth needed to detect the collapse danger beforehand.
The North Dakota incident was fortunate in that the remote location meant few residents were affected when 29 of the train’s 151 cars left the tracks. Just two households chose to evacuate for two days while emergency crews extinguished fires and managed the methanol and anhydrous ammonia releases. A dozen additional derailed cars were transporting plastic pellets.
The derailment itself caused no injuries, though several cleanup workers later sought medical attention and experienced health issues after exposure to anhydrous ammonia.
CPKC spokesman Patrick Waldron stated the company obtained the report following its Thursday afternoon release and is conducting a thorough review.
Representatives from the Pipelines and Hazardous Materials Safety Administration and the Association of American Railroads trade organization did not immediately respond to inquiries about the NTSB conclusions. The Federal Railroad Administration also declined immediate comment on the recommendations.
The NTSB has advocated for eliminating these cars from hazardous materials service since at least the 1990s due to their problematic track record, and Congress has required their replacement for transporting flammable liquids by 2029. However, they would still be permitted for carrying other dangerous materials beyond that deadline.
