Seven train cars derailed when the bridge over the Mantua Creek collapsed Friday morning. Four tank cars containing vinyl chloride were dumped into the creek. Nearby residents were evacuated and schools were locked down. Nearly 20 people complained of respiratory distress from the vinyl chloride vapor that leaked from the tank cars. (Photo: Rae Lynn Stevenson/South Jersey Times. All rights reserved.)
On November 30, 2012, a train transporting the chemical vinyl chloride derailed while crossing a bridge that collapsed over Mantua Creek, in Paulsboro, N.J., near Philadelphia. Four railcars fell into the creek, breaching one tank and releasing approximately 23,000 gallons of vinyl chloride.
Local, state, and federal emergency personnel responded on scene. A voluntary evacuation zone was established for the area, and nearby schools were ordered to immediately take shelter and seal off their buildings.
Vinyl chloride, which is used to make plastics, adhesives, and other chemicals, is a toxic gas. During this accident, most of the chemical was released directly to the air, and it appears none of it ended up in the creek.
However, there was a possibility that a significant amount of vinyl chloride could have been released into the water when the railcars carrying it tumbled into Mantua Creek, which feeds into the Delaware River. Atlantic sturgeon, a threatened species, are known to spawn where Mantua Creek meets the Delaware, and when dissolved in water, vinyl chloride is toxic to fish.
U.S. Coast Guard Sector Del Bay contacted NOAA’s Office of Response and Restoration (OR&R) and requested scientific support for this environmental and public health threat. The OR&R scientific support team worked to address early concerns about the air hazard, centering around possible health effects, evacuation decisions, proper protective equipment for responders, impacts to the Philadelphia airport two miles away, and reactivity between vinyl chloride and another rail car containing ethyl alcohol. OR&R develops software products responders use to address these issues: ALOHA, an air dispersion model, and CAMEO Chemicals, a hazardous material database.
By later in the day the situation was considered stable. The air hazard was under control, and no chemicals were spilled into Mantua Creek.
