Residents living near a railroad tanker car that released a hazardous chemical, sickening 23 people, were allowed to return home Saturday night, officials said.
An evacuation notice for 44 homes had been issued Saturday morning because the temperature inside the rail car, which was leaking styrene, was increasing and its pressure relief valve apparently was not working.
“There’s no appreciable pressure inside the tank,” said Matt Higgins, an environmental scientist with the Delaware Department of Natural Resources and Environmental Control. “We don’t anticipate any additional impact to the surrounding community.”
The car is parked at the Dow Reichhold Specialty Latex plant, which was evacuated Friday evening. Twenty-three people were treated for flulike symptoms and released.
None of the injured were plant workers, said Reichhold site manager Michael Galbus.
No chemicals have been released since around midnight, said Jamie Turner, director of the Delaware Emergency Management Agency. The cause of the release remained unknown.
Equipment added to car weeks ago
An inhibitor was added to the tank car several weeks ago at the recommendation of the supplier, Chevron Phillips, Galbus said. He refused to speculate on whether the inhibitor was working properly but said it was meant to prevent polymerization, a chemical reaction that officials cited as the reason for the temperature increase inside the tanker.
On Friday night, people living within five miles had been asked to stay indoors. The restriction on residents more than 1,500 feet away was lifted late Saturday morning.
Victoria Brown, 44, who lives within about a mile of the plant with her mother and two brothers, said they spent the night in cars parked outside Dover High School, where the American Red Cross has set up a shelter.
“They just had the little floor mats,” Brown said.
The Red Cross later brought in cots and additional supplies to accommodate the evacuees.
Styrene is used by chemical companies that make plastics, synthetic rubber, resins and insulators, according to the Environmental Protection Agency’s Web site. Styrene vapor irritates the eyes, the nose, and the throat and can adversely affect the human nervous system.