New findings in an investigation have determined the cause of the train derailment in Raymond earlier this year.

The National Transportation Safety Board released a report on the train derailment that resulted in the town of Raymond being evacuated. It highlights a “catastrophic rail failure” that led to the derailment and spill of ethanol and corn syrup.

As previously reported, a northbound BNSF Railway local freight train derailed in Raymond due to an in-service broken rail on March 30.

Post-accident inspections and evidence indicated that track and train dynamics worsened a rail head surface until a complete sectional break of the rail head occurred underneath the train.

The incident resulted in 23 mixed freight rail cars being impacted — rail lines 9-21 went on their sides, while lines 22-32 derailed in an accordion style near the point of derailment.

The report states that there were 14 loaded hazardous materials cars throughout the train, with ten cars containing ethanol.

A 1/2-mile evacuation radius impacting about 800 residents in Raymond was implemented, with no fatalities or injuries being reported.

On-scene tank car inspections were completed on April 1 and preliminary findings showed that hazardous materials were released from five breached tank cars. Two of the tank cars sustained punctured shells that released ethanol, which then ignited and destroyed the manway gaskets of three additional tank cars.

According to the report, the thermally damaged manway closures had been sealed with elastomeric butadiene acrylonitrile gaskets that, according to the manufacturer data, could sustain temperatures of up to 225 degrees Fahrenheit.

The insufficiency of the thermal protection system and the regulations and standards for gaskets used in tank car service equipment are being addressed as part of the investigation.

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