Three tanker cars carrying chlorine jumped the tracks Friday morning in Magnolia, Arkansas.
It happened about 8:30 am near the former Alcoa and Unit Structures facility.
No injuries were reported and none of the tank cars ruptured, however authorities evacuated the campus of Southern Arkansas University as a precaution.
People living near the plant were not immediately evacuated, but they will be asked to leave once railroad crews begin picking the wrecked tanker cars up.
The cars were headed to a plant in McNeil, Arkansas.
Officials think the train cars derailed because of a break in the tracks.