EAST PALESTINE, Ohio (NewsNation) — Communication and training were pain points for the agencies that responded to the Feb. 3 toxic chemical train derailment in East Palestine, Ohio, witnesses said at hearing Thursday.

Among the key details delayed by communication breakdowns was which hazardous chemical the derailed train was carrying. About an hour passed before responders learned what was on the train, even though the rail company Norfolk Southern sent that information to its contractor minutes after the wreck, National Transportation Safety Board (NTSB) chairwoman Jennifer Homendy pointed out.

“It is not the fire service’s responsibility to drive a mile up and find a train crew while they’re trying to deal with a terrible incident, Homendy said. “It is the railroad’s responsibility to maintain that and provide that information, according to federal regulations.”

The National Transportation Safety Board (NTSB) on Thursday began its two-day investigative hearings examining the catastrophic Norfolk Southern train derailment in East Palestine.

Thursday’s hearing focused on the emergency response to the derailment and the crucial decision officials made days later to release the toxic vinyl chloride in five tank cars and burn it to keep those cars from exploding.

It led to the deaths of aquatic life, the evacuation of hundreds of families and the contamination of the town’s water and soil.

Since then, residents have been advocating for answers regarding potential health and personal consequences. Many continue to report inexplicable health issues.

During questioning Thursday, East Palestine Fire Chief Keith Drabick called communication a “ginormous issue in this county.”

“The first challenge of course was communication — being able to communicate with all the other agencies coming in, being able to get those agencies there and get them on the correct side of the tracks that we needed them on, and then just overall coordination of the incident,” Drabick said.

Notably, there were delays in getting first responders’ information about what was in the derailed cars.

An app called AskRail might have helped them access that information sooner and guide them through how to act. Responders, however, didn’t have access to the app, which requires special permissions.

Additionally, dispatchers at the time of the derailment were overwhelmed with radio traffic calls, Drabick said.

“Our dispatch center dispatches three fire departments and one and two police departments ,” he said. “So something of this magnitude is overwhelming to them…a centralized 911 center would be a great step forward to solving the communication problem.”

Training requirements for those on the scene also varied. Volunteer firefighters, for example, receive 36 hours of initial training upon certification. That’s compared to the 200 hours of training that professional firefighters receive, witnesses said.

Although Drabick said there should be “standard training across the board” for both volunteer and professional firefighters, he acknowledged that setting more stringent requirements would likely limit the pool of available volunteers.

“The majority of the fire departments in this country operate as volunteer fire departments, men and women working full-time jobs elsewhere, sacrificing their time coming in the evenings or days if they’re off.”

On Wednesday, Homendy hosted a community meeting, addressing plans and emphasizing transparency.

A resident raised a question on Norfolk Southern train video footage, to which Homendy responded, “We did not get all the video from Norfolk Southern. They’re not required to collect 12 hours, but some of it was overwritten. We did get a portion of it.”

NewsNation’s Rich McHugh had an exclusive interview with Mark Durno, the EPA official in charge of operations, raising concerns regarding the safety of residents, the findings of independent testing regarding dioxins, the decision to burn vinyl chloride-filled tank cars and the criticism surrounding their actions in East Palestine.

Rich asked, “At any point during that process, did the U.S. EPA say, ‘Hey, guys, this might not be a good idea to burn five tankers of vinyl chloride over this town?'”

“Not that I’m aware of,” Durno responded “When you’re dealing with the emergencies like this and you have to make decisions on a very critical pathway, I don’t see where another decision was possible.”

Watch NewsNation’s Rich McHugh’s full exclusive interview on “Elizabeth Vargas Reports” Thursday at 6 p.m. EST.

According to the EPA, despite the independent testing revealing the presence of dioxins, their data indicates that is safe for residents in East Palestine.

Since the Feb. 3 derailment, Norfolk Southern has been working to dig up and remove contaminated soil and water from the derailment site. The EPA and Ohio officials have been overseeing the cleanup.

Norfolk Southern has committed more than $62 million to help the town recover. The railroad has said it expects the derailment to cost it nearly $400 million, although insurance will cover some of that and any other companies that are found responsible may have to contribute. But the total cost will likely increase over time as various lawsuits filed by states, the federal government and residents work their way through the courts.

The NTSB said in its preliminary report that an overheating bearing on one of the railcars likely caused the derailment, but it may take more than a year before the agency publishes its final report. The bearing started heating up miles before the derailment, according to sensors Norfolk Southern has along the tracks, but it didn’t get hot enough to trigger an alarm until just before the crash. The crew had little time to react.

The derailment, along with several others since February, has generated nationwide concern regarding railroad safety and prompted members of Congress to propose a package of reforms.

All the Democrats on the House Committee on Oversight and Accountability sent Shaw a letter that was released Thursday morning expressing frustration that his railroad has refused to produce documents they asked for related to the way it uses trackside detectors and some of the operating decisions Norfolk Southern has made in recent years as it slashed its workforce to reduce costs.

The railroad has followed the industry practice to rely more on running fewer, longer trains so it doesn’t need as many crews and locomotives. Rail unions have raised concerns about whether all the cuts have made railroads riskier, while executives have defended their approach.

Norfolk Southern’s lawyers told the congressional committee that the railroad couldn’t release the internal documents because of the ongoing NTSB investigation. Committee Democrats have rejected that explanation and said nothing about the NTSB probe should keep the committee from looking into the matter and the railroad knows that. So far, the railroad has provided only two small batches of documents that appear to be publicly available.

“We are profoundly troubled by Norfolk Southern’s illegitimate efforts to mislead Committee Democrats and use NTSB’s investigation as a shield to impede Congressional oversight,” the 21 Democrats wrote in their letter.

NewsNation digital reporter Katie Smith and The Associated Press contributed to this report.