The National Transportation Safety Board released thousands of pages of documents on Thursday about the derailment of a Norfolk Southern freight train in East Palestine, Ohio, providing the fullest account yet of what had led to the accident.
The agency released the trove of documents ahead of a two-day hearing in East Palestine, which began on Thursday. The hearing is examining several aspects of the derailment and the emergency response that followed, including the decision to conduct a controlled burn of some toxic chemicals the train was carrying.
The N.T.S.B. held a community meeting on Wednesday night to field questions from residents, and the agency’s chairwoman, Jennifer Homendy, opened the hearing on Thursday with a message for those affected by the derailment.
“Just know that all of us think about you, not just during this hearing, not just during the investigation, but well after our final board report is issued,” she said.
The N.T.S.B. had previously said that a wheel bearing on one of the rail cars had overheated as the 149-car train passed through Ohio on Feb. 3. The documents released on Thursday offered a more detailed picture of what happened in the moments before the train left the tracks and how officials responded to the derailment and the fire that ensued.
According to the documents, a part of the rail car’s wheel set came off, leading to the derailment. The wheel bearing that overheated was found just over 100 feet from the point of derailment and had “extensive thermal damage,” the safety board said.
Ultimately, 38 cars ended up derailing, including 11 that contained hazardous materials, according to the agency.
No one died or was injured in the accident. In its aftermath, officials said they had not detected dangerous levels of chemicals in the air or the municipal water system. But some people experienced symptoms like rashes and headaches, leaving residents to worry about potential long-term health risks stemming from the release of toxic chemicals.
The Justice Department sued Norfolk Southern in March over the derailment, and the N.T.S.B. opened a special investigation into safety practices at the company. The incident also prompted a bipartisan effort in Congress to pass new rail safety legislation. At a Senate hearing in March, Norfolk Southern’s chief executive, Alan H. Shaw, told lawmakers that he was “deeply sorry” for the effects of the derailment.
On Thursday, the N.T.S.B. hearing focused in part on the decision to vent vinyl chloride, a toxic flammable gas, from five tank cars and burn it off to avoid a possible explosion. The action, three days after the derailment, released chemicals into the air around East Palestine and led to huge smoke plumes.
According to a transcript released before the hearing, the East Palestine fire chief, Keith A. Drabick, told investigators that he “kind of got blindsided” when Norfolk Southern and its contractors sought to undertake that procedure because they believed the vinyl chloride was having a chemical reaction, known as polymerization, that could lead to an explosion.
Chief Drabick said he was given only 13 minutes to decide whether to give his approval, because there was a desire to undertake the procedure during daylight hours, according to the transcript. Employees of the company that produced the vinyl chloride, OxyVinyls, did not see obvious signs of polymerization, according to the materials released on Thursday.
But Norfolk Southern sought to vent and burn the vinyl chloride in part because pressure release devices on the tank cars appeared to be plugged, which it attributed to polymerization.
“Eventually, if we did nothing, the cars were going to go through a violent explosion,” Robert Wood, Norfolk Southern’s director of hazardous materials, said at the hearing. “We believed our only alternative left was a vent and burn.”
The materials released on Thursday documented the train’s journey on its way to eastern Ohio. It encountered mechanical problems twice on the day before the derailment, requiring a stop in Illinois and an emergency brake application in Indiana, according to investigators.
The train was 1.75 miles long, and on the day before the accident, the train’s engineer voiced concern about its size, according to a report that described the engineer’s account. But the yardmaster replied, “Well, this is what they want,” according to the report. The engineer on a relief crew that came on duty said, “It handled really, really well for an 18,000-ton train.”
Early in the afternoon on Feb. 3, a new crew took over the train, consisting of an engineer with 27 years of experience, a conductor with less than a year of experience and a conductor trainee.
Overheated wheel bearings are a major cause of derailments. As part of the East Palestine inquiry, investigators looked at sensors that Norfolk Southern places alongside its tracks to provide alerts when overheating occurs, known as hot-bearing detectors. They found that the detectors leading up to East Palestine had worked, but the materials released by the N.T.S.B. revealed that a Norfolk Southern employee working in a monitoring center in Atlanta did not initially see an alert showing that the bearing was heating up.
That alert came from a detector roughly 20 miles from where the train derailed, and it showed the bearing’s temperature to be 103 degrees above the ambient temperature, up from the 38 degrees that an earlier detector had registered. “Honestly, I didn’t see it when it first came in,” the employee told investigators, saying he was looking at alerts from three other trains.
By the time the train traveled over the next detector, in East Palestine, the bearing’s temperature had soared to 253 degrees above the ambient temperature. That reading set off a critical alarm for the train’s crew, who began stopping the train and called into the monitoring center. It was then that the employee there noticed the earlier 103 degree reading. But he had not received the latest, critical reading because the readings do not come in until the entire length of the train has traveled over a detector. The train derailed soon after.
Norfolk Southern’s monitoring center “functioned as it was supposed to with respect to train 32N,” Connor Spielmaker, a spokesman for the company, said in an email, referring to the derailed train. He added that the initial alert did not require that the train be stopped and was “a first data point to begin monitoring as it passes over subsequent detectors.”
Mr. Spielmaker said the train’s crew “operated the train below the track speed limit and handled the train in an approved manner.”
After the derailment, there have been calls to place hot-bearing detectors closer together to increase the likelihood that overheating can be discovered earlier, allowing crews to stop trains before they derail.
A rail safety bill proposed in the Senate initially required that the detectors be 10 miles apart on tracks used by trains carrying hazardous materials, but a later version of the bill imposes a looser requirement. The legislation is awaiting a vote by the full Senate.
Daniel McGraw contributed reporting from East Palestine, Ohio.
