BISMARCK, N.D. — Federal investigators have determined that 400,000 gallons of oil was lost last month when a train derailed and caught fire in North Dakota, according to a report released Monday.
The derailment on Dec. 30 has highlighted concerns about shipping crude by rail. It also led to a safety alert from the U.S. Department of Transportation warning about the potential high volatility of crude from the Bakken oil patch in eastern Montana and western North Dakota.
According to the National Transportation Safety Board's preliminary report released Monday, the eastbound train derailed after crashing into a grain car that had fallen onto the track after a westbound train carrying soybeans derailed. The NTSB is studying what role a broken axle might have played in the derailment of the grain train.
The derailments of the two BNSF Railway trains sparked massive explosions about a mile from Casselton, a town of about 2,400 residents in southeast North Dakota. No one was hurt, but about 1,400 people voluntarily evacuated.
How much of the 400,000 gallons of oil that was lost in the derailment burned off and how much spilled into the ground is unclear.
"We do know where the grossly contaminated soil is," said Dave Glatt, chief of North Dakota Department of Health's environmental health section.
He said about 25,000 gallons of oil was recovered from wrecked oil tankers. Each tank car can carry about 650 barrels, or more than 27,000 gallons of oil.
The NTSB said 21 of the 106 cars on the oil train derailed, along with the two leading locomotives. Twenty of the cars were carrying oil and 18 were punctured. Damage is estimated at $6.1 million, the report said.
"With the cleanup ongoing, that is not a final cost," said BNSF spokeswoman Amy McBeth said.
Glatt said about 1,300 tons of oily dirt has been removed so far from the crash site and sent to an industrial landfill in north-central North Dakota.
McBeth said at least 6,000 more tons of dirt is expected to be removed during the cleanup
North Dakota regulators are on site monitoring the cleanup that's being done by a BNSF contractor, Glatt said.
The NTSB's preliminary report said the grain train was traveling at about 28 miles per hour when 13 of its 112 cars left the tracks. The train carrying oil was travelling at about 42 miles per hour when it collided with one of the grain cars. Investigators said the maximum speed on the tracks near Casselton is 60 mph.
Casselton Mayor Ed McConnell said tangled wreckage was still strewn at the crash site on Monday.
"Almost all of it is still here," McConnell said. "They've got it piled off to the side but it would be nice if they'd get it out of here."
McBeth said crews are working clear the wreckage by cutting it up and hauling it away.
"The amount of time it has taken is pretty typical," McBeth said. "It takes a while to cut them up and removed."
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