Updated: 07/22/2014 7:08 PM
Created: 07/22/2014 1:36 PM KSTP.com
A massive fire at an oil supply company was burning itself out Tuesday afternoon, 12 hours after it began in an industrial part of the western North Dakota oil patch town of Williston.
Authorities had not said as of Tuesday afternoon what caused the fire at Red River Supply, which Williams County Emergency Manager Mike Hallesy said broke out about midnight Monday. Company officials did not immediately respond to requests for comment and law enforcement wouldn't let anyone past the half-mile evacuation border.
Department of Health Air Quality Division director Terry O'Clair said local fire departments are letting the blaze burn itself out. He also said a National Guard hazmat unit is heading to the scene, which is in an area east of downtown filled with warehouses and businesses that service the oil industry.
A large cloud of gray smoke hovered over Williston on Tuesday morning. The North Dakota Department of Health and other agencies are monitoring air quality near the site for any potential threat, according to agency spokesman Tim Wiedrich. Williston Mayor Howard Klug said a hazmat unit that monitored air quality Tuesday morning found nothing of concern.
Klug visited the scene with emergency workers on Tuesday afternoon and told The Associated Press "it'll take days" to figure out the cause of the fire based on his conversations with responders.
The FAA issued a six-hour temporary flight restriction that lasted until 2 p.m. Tuesday for Sloulin Field International Airport, airport manager Steven Kjergaard said, and there is still a flight restriction directly to the southeast.
"Planes can only arrive and depart from the west," Kjergaard said.
O'Clair said the good news is that the plume of smoke is not blowing in the direction of the city.
"If it starts drifting toward the city that would be a concern," he said. O'Clair also said that fire crews were limiting the use of water in order to reduce contamination.
Red River Supply's site has rail spurs for loading and unloading liquids such as crude oil, and dry goods, according to its website. The company's website also says it provides storage, blending and delivery of drilling fluids, such as calcium chloride, calcium bromide, calcium nitrate and pot ash.
Emergency responders are expected to remain on scene for the next day or two, Hallesy said.
Roads are closed near the site, including a stretch of State Highway 1804.
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