Norfolk Southern freight train 15T derailed 27 cars, resulting in the release of oleum or fuming sulfuric acid.

On the morning of the derailment, Norfolk Southern train 703 approached the spring switch at the west end of the Boyd Siding and was given a signal restriction.

The crew immediately noted a white cloud rising from the derailed cars and radioed the dispatcher at the same time as the signal maintainer was calling the incident in via telephone.

[2] The result of this spill was a large plume of acid vapors, that began to envelop the area and drift southeast with the prevailing wind.

Responders from the Rural/Metro Fire Department and Knox County Sheriffs Office began to arrive within five minutes and met with the train crew.

As a result of incidental exposure to the toxic cloud, 15 residents and two law enforcement officers were treated and released from local hospitals for irritation.