The National Transportation Safety Board (NTSB) has released a preliminary report for its ongoing investigation of the July 5, 2025, CN train derailment with hazardous materials release and subsequent fire near Glendora, Miss.
What Happened?
At about 2:26 p.m. local time, a southbound CN mixed-freight train derailed 22 railcars on the Yazoo subdivision at milepost 97.63, according to the NTSB, which published its report on Aug. 5 and noted that the information is “preliminary and subject to change.” One of the derailed railcars, a Department of Transportation Specification 111A100W1 loaded with the benzene, breached and caught fire. “There were no reported fatalities or injuries, and about 160 people were evacuated in a 1 mile radius of the accident,” the agency said. At the time of the accident, visibility conditions were clear, and the weather was 90°F with no precipitation. CN estimated damages to be about $1.5 million, the NTSB said.
The train, whose crew included one engineer and one conductor, had departed Memphis, Tenn., around 11:08 a.m., destined for Baton Rouge, La. It was a key train, which the NTSB defined as “a train with any one of the following components: at least one tank car containing anhydrous ammonia, ammonia solutions, or material designated as a poison or toxic inhalation hazard; 20 railcar loads of any combination of hazardous material; or one or more railcar loads of spent nuclear fuel or radioactive waste.” The 139-car train comprised 59 loaded railcars and 80 empties, including 11 residue cars, which are defined as empty tank cars that have “not yet been refilled or cleaned of hazardous material and purged to remove any hazardous vapors,” with 23 hazmat tank cars. Of the 23 hazmat tank cars, the NTSB said, one was loaded with compressed gas (refrigerant), 16 were loaded with benzene, and six were loaded with petroleum. The train was traveling about 29 mph on a right-hand curve near milepost 97.63 when NTSB said it experienced a train-initiated emergency brake application and derailed railcars 29 through 50.
According to the agency, a few days before the accident, on July 2, a CN autonomous track inspection vehicle “noted two superelevation track defects in the area of the derailment, which CN reported were addressed by a track surfacing unit on July 3.” In accordance with operational procedure, it said, CN subsequently placed a 10 mph speed restriction on that segment of track for the next two trains and then raised it to 30 mph on July 3. At the time of the accident, the speed restriction of 30 mph was still in place for the segment of track on which the accident occurred.
Local emergency responders and CN hazmat responders extinguished the fire around 11:30 p.m. on July 5, the NTSB reported, and the evacuation order was lifted shortly thereafter. CN contractors removed about 25,000 gallons of product from the breached benzene tank car. The “product,” the NTSB said, included both the material itself and water used in firefighting activities.
While on scene, the NTSB reviewed data from locomotive event recorders and inward- and outward-facing image recorders, inspected train equipment and track structures, reviewed CN’s engineering standards and procedures, and completed interviews.
NTSB’s investigation is ongoing. “Future investigative activity will focus on CN’s procedures related to track inspections, engineering defect mitigation, employee training and testing, and emergency response,” it reported.
Parties to the investigation include the Federal Railroad Administration; Pipeline and Hazardous Materials Safety Administration; CN; International Association of Sheet Metal, Air, Rail and Transportation Workers; Brotherhood of Locomotive Engineers and Trainmen; and Brotherhood of Maintenance of Way Employes Division.
According to the NTSB, the timing between the beginning of an investigation and a probable cause determination and report varies based on the complexity of the investigation and the workload of the agency’s investigators. In general, the NTSB said it tries to complete an investigation within 12 to 24 months, “but these and other factors can greatly affect that timing.”
