Gases burned off from derailed train cars in Matteson, trains operating again

In the day following the derailment, CN said it would be conducting a controlled flaring of 11 cars that contain a residue amount of liquid petroleum gas.

The controlled burn to remove leftover gases from derailed train cars in Matteson was completed, officials announced Sunday, one day after train movement resumed along the tracks.

Canadian National, which operates the train in question, said flaring had been finished at the site where approximately 25 railcars derailed on Thursday. An evacuation order was initially issued to residents after "propane residue" leaked from one of the train cars.

That substance was quickly contained and the evacuation order was lifted within hours, officials said, emphasizing there was no ongoing danger to the public. In the day following the derailment, CN said it would be conducting a controlled flaring of 11 cars that contain a residue amount of liquid petroleum gas.

"...There is no danger to public safety or to the environment..." the railroad said in a statement. "It is required to eliminate any left over product and allow for the safe removal of the railcar. Out of an abundance of caution, CN will be monitoring air quality."

CN said Sunday that clean-up and remediation at the site will continue "over the next few weeks." Crews will remove railcars, repave the road and refurbish the crossing, the railroad said.

The cause of the derailment remained under investigation late Sunday.