After health experts determined that air quality was safe within city limits, officials in Casselton, N.D., on Tuesday afternoon lifted a voluntary evacuation order that had been issued after a collision involving a train carrying crude oil released clouds of noxious billowing smoke.
Cass County Sheriff Paul D. Laney lifted the voluntary evacuation order at 3 p.m. The sheriff's office estimated that, as of Tuesday morning, 65% of Casselton's 2,432 residents had evacuated.
Steven Forsberg, a spokesman for the Burlington Northern Santa Fe Corp. railroad, told the Los Angeles Times that the accident occurred when a train hauling grain derailed on a track parallel to an eastbound train carrying crude oil. Cars from the two trains collided, setting off explosions and fires.
Laney's decision came after consulting with Cass County Health Officer Dr. John Baird, the North Dakota Department of Health-Division of Air Quality, Fargo Cass Public Health Environmental Health Division and other experts, who determined that residents could safely return to their homes.
However, residents "directly one mile south of the incident location are advised to use extra caution upon returning to their homes," the sheriff's office said.
National Transportation Safety Board officials will remain on site to continue conducting their investigation. Burlington Northern Santa Fe crews will also stay, "working to clear wreckage and extinguish any smoldering fires," the sheriff's office said.