As part of Norfolk Southern’s settlement of federal probes into an Ohio train derailment last year, the railroad is creating a work group to study the type of decision that was made to burn off toxic chemicals in the wake of the fiery wreck.

The “vent and burn” procedure conducted days after the February 2023 wreck in East Palestine, Ohio, caused a large and noxious black plume of toxic vinyl chloride over the town, and the decision to do the burn has drawn harsh scrutiny and criticism.

While Atlanta-based Norfolk Southern has said the decision was made because of risks of a calamitous explosion, a chemical shipper told Norfolk Southern it did not believe there was a chemical reaction in the cars posing risk of an explosion. The decision on the vent and burn was made by a Unified Command, including key officials who did not know about the chemical shipper’s perspective, according to remarks during a federal hearing last year.

National Transportation Safety Board Chair Jennifer Homendy said earlier this year that the chemical shipper believed “there was no justification to do a vent and burn” of the five tank cars filled with vinyl chloride, and that officials could have just let the tank cars cool down.

In May, Norfolk Southern reached a settlement of more than $310 million to end claims and investigations by the U.S. Department of Justice and the U.S. Environmental Protection Agency related to the East Palestine derailment.

Subject to final court approval of the settlement, Norfolk Southern said Friday it will convene the Vent and Burn Workgroup of “leaders from across stakeholder groups who have a role to play in responding to rail accidents.”

The group will assess current practices and protocols and aim to improve the response to a derailment.

“There is no finish line when it comes to improving safety,” Norfolk Southern Chief Safety Officer John Fleps said in a written statement.

In addition to paying for the cleanup, Norfolk Southern is also agreeing to make safety improvements.

The Justice Department said in a news release on the settlement last month that Norfolk Southern will create and adopt a procedure to coordinate with government officials and others before any vent and burn proposed by the company.

Norfolk Southern has tallied about $1.7 billion in charges in response to the East Palestine derailment, as of its most recent quarterly results. That figure includes settlement costs.