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Train Derails, Chlorine Leaked

Gas cloud blankets area near San Antonio, killing three

by Marc S. Reisch
July 5, 2004 | A version of this story appeared in Volume 82, Issue 27

Two freight trains collided early on June 28 in a rural area just 15 miles west of San Antonio, Texas, killing a conductor, derailing 40 cars, and releasing a cloud of chlorine that drifted for miles and killed two more people.

According to reports from the area, about 50 people were hospitalized after being exposed to the gas cloud. Search crews found the bodies of two people in a house not far from the crash site; their deaths, according to the local medical examiner, were related to the inhalation of chlorine.

The collision occurred when a Union Pacific train heading west toward Arizona struck a Burlington Northern Santa Fe train with 123 empty cars heading east to Tulsa, Okla., a Union Pacific spokesman says. The eastbound train was moving to a siding. However, the Union Pacific train did not wait for the other to finish pulling over and hit it broadside at about 20 mph.

Union Pacific was hauling one tank car of chlorine. It derailed and leaked about two-thirds of its contents. Two days after the accident, crews had plugged the leak in the car and were moving it to a safe site, the spokesman says. Seven tank cars carrying ammonium nitrate were also involved, but the spokesman says it was unclear how many of those were breached.

A spokeswoman for the National Transportation Safety Board says nine investigators are now on-site leading an investigation with assistance from the Federal Railroad Administration and the Railroad Commission of Texas. The engineers and transport workers unions are also involved in the investigation, as is the chlorine tank-car maker, American Railcar. It will take at least a year to investigate and report on the accident, the spokeswoman notes.


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