WASHINGTON — Crude oil produced in North America's Bakken region may be more flammable and therefore more dangerous to ship by rail than crude from other areas, a U.S. regulator said after studying the question for four months.
The Pipeline and Hazardous Materials Safety Administration announced its preliminary conclusion three days after a BNSF Railway Co. train carrying oil caught fire after a collision in Casselton, N.D.
The North Dakota accident is the fourth major North American derailment in six months by trains transporting crude. Record volumes of oil are moving by rail as production from North Dakota and Texas has pushed U.S. output to the most since 1988 and pipeline capacity has failed to keep up.
The regulator "is reinforcing the requirement to properly test, characterize, classify, and where appropriate sufficiently degasify hazardous materials prior to and during transportation," it said in a safety alert posted on its website Thursday.
The agency's findings may expedite the rail industry's push for stronger tank cars for moving crude and other hazardous materials. It strengthens calls for the petroleum industry to accurately label tank-car contents and test shipments to make sure they don't contain gases produced in the hydraulic fracturing process.
"We believe there is sufficient cause for concern," about whether crude shippers are properly labeling tank cars' contents, Jeannie Shiffer, a pipeline-regulator spokeswoman, said in an e-mail. "That is why PHMSA and FRA issued a safety advisory earlier this summer, why we are conducting Operation Classification and why we are issuing today's safety alert."
U.S. regulators, including the Federal Railroad Administration, began examining whether Bakken crude is more risky to move by rail following an explosion of railcars carrying North Dakota crude in Lac Megantic, Quebec. The agencies Thursday said those inspections will continue. About three-quarters of the oil produced in North Dakota is shipped by rail rather than pipeline.
The "implications for cost and speed of crude out of the Bakken as a result of today's safety alert are likely to depend on the rulemaking" that follows, Kevin Book, managing director for research at ClearView Energy Partners LLC in Washington, said in an e-mail. "We expect that the North Dakota accident will bring a proposal sooner rather than later."
The boom in hydraulic fracturing, in which water, sand and chemicals are shot underground to break apart rock and free the fuel, helped North Dakota pass Alaska in 2012 to become the second-largest onshore producer of oil among U.S. states. Output from that state's portion of the Bakken formation was up by 250,000 barrels per day in September from a year earlier, according to the U.S. Energy Information Administration.
Some supporters of the proposed Keystone XL Canada-U.S. pipeline say rail accidents buttress their argument. Opponents of the project by TransCanada Corp. of Calgary point to spills in Alabama, Michigan
and North Dakota to show that method of transporting oil carries its own hazards. In September, a Tesoro Corp. pipeline ruptured and spilled 20,000 barrels of crude in northwest North Dakota.
Led by production from underground shale, U.S. oil output grew 18 percent in the past 12 months, the fastest pace on record, boosting fuel exports and reducing reliance on imports, according to the energy information agency. The boom will make the U.S. the world's largest producer by 2015, the International Energy Agency said last year.
The oil carried on the train that crashed in Quebec, killing 47 people, in July was improperly labeled as a less volatile liquid with a lower level of hazard, Canada's Transportation Safety Board said in September. The crude was being delivered to Irving Oil's refinery in Saint John, New Brunswick, from the Bakken region. The Bakken shale formation is in northwestern North Dakota and eastern Montana.
Crudes carried in tank cars are classified as flammable liquids and then divided into so-called packing groups based on their level of hazard, with PG I being the most hazardous and PG III being the least. The Bakken oil being transported by the train that derailed in Quebec was described as PG III when it should have been PG II, the board said.