At approximately 2:00 PM on Tuesday, May 28, 2013 a CSX train hit a rolloff truck that was crossing at an at-grade railroad crossing, causing the train to derail. Subsequent to the derailmant, a car containing sodium chlorate apparently exploded, causing nearby cars of terephthalate acid (TPA) to burn. There was one car of sodium hydroxide and one car with fluorosilicic acid residue involved in the derailment, but these cars were not compromised. The fire burned until approximately midnight. Multiple fire departments were onscene, with Baltimore County as the lead. The Maryland Department of the Environment and an EPA OSC were onscene. Air monitoring of the incident was being conducted by the Fire Departments and CSX.