About 65% of residents in the small town of Casselton, N.D., remained evacuated Tuesday after a train carrying crude oil collided with another train and exploded a mile west of town Monday afternoon, sending noxious smoke billowing into the air, officials said.
Although the air quality was improving Tuesday, Mayor Ed McConnell had urged people to leave overnight when winds blew the potentially hazardous smoke toward Casselton, which has a population of 2,432 and is about 20 miles west of Fargo.
Cass County Sheriff Mitch Burris said no injuries or deaths were reported in the Monday afternoon collision.
The National Transportation Safety Board is conducting an investigation into the cause of the crash. Officials at the Centers for Toxicology and Environmental Health are assessing air quality.
Amy McBeth, public information officer for Burlington Northern Santa Fe Railroad, said Tuesday that the railroad also has a hazardous materials crew on site.
“All entities involved will determine when it is safe for residents to return and communicate those decisions as soon as they are made,” a statement from the Cass County Sheriff's office.
Following the accident, some residents sought refuge at an emergency shelter set up at Discovery Middle School in Fargo. A claims hotline and local claims center to help displaced residents will open on Thursday.
Officials first received reports of the collision at 2:10 p.m. on Monday.
Steven Forsberg, a spokeswoman for the railroad, told The Times that the accident occurred when a grain train derailed on a track parallel to an eastbound crude oil train. The explosions and fire erupted after cars from the grain train struck some of the oil tank cars, he said.
"A fire ensued, and quickly a number of the cars became engulfed," Sgt. Tara Morris said on Monday.
Local residents and media captured images of large explosions and a pillar of smoke coming out of the flaming wreckage.
The North Dakota crash is the fourth serious accident involving trains hauling crude in North America this year.
In July, an unattended train with 72 tank cars carrying crude oil from North Dakota’s Bakken shale fields rolled downhill and set off a major explosion in Lac-Megantic, Quebec, killing more than 40 people.
Two other accidents followed shortly after, though neither involved fatalities.
The accidents have put a spotlight on the growing reliance on rail to move surging oil production from new fields in Texas, North Dakota and Colorado.
U.S. railroads are moving 25 times more crude than they did in 2008, often in trains with more than 100 tank cars that each carry 30,000 gallons.
In the aftermath of the accidents, the Federal Railroad Administration issued an emergency order that tightened operating rules on carrying crude, prohibiting operators from leaving crude trains unattended without getting prior regulatory approval. Separately, the federal Pipeline and Hazardous Materials Safety Administration began steps to improve the safety of tank cars.
Times staff writers Matt Pearce and Ralph Vartabedian contributed to this report.