A federal safety alert Thursday warned that crude oil flowing out of new fields in North Dakota may be more flammable than expected, a caution that comes several days after a train carrying about 3.5 million gallons of the same oil crashed in the state and set off a massive explosion.
The accident on the BNSF Railway, the fourth such explosion in North America involving crude oil trains, has fed mounting concerns over public safety as the rail industry sharply increases the use of rail to transport surging crude production in North Dakota, Texas and Colorado.
Following the latest derailment and crash, which forced the evacuation of more than 1,000 residents from the town of Casselton, the National Transportation Safety Board has launched the nation's first broad examination of the safety of moving petroleum by rail.
Trains carrying oil have multiplied across the country as environmental concerns and political maneuvering have delayed approval of a major new pipeline to transport oil to Gulf Coast refineries. The issue may be most crucial for cities in the West, which were often founded and developed by railroads so that main lines go directly through the centers of today's urban areas.
Crude oil shipments by rail have shot up 25-fold in the last several years as producers rush oil from newly developing shale fields to market. California alone has seen a fourfold increase over the last year, with current shipments of about 200,000 barrels a month.
Refinery operators this summer unveiled a plan to build a rail loading facility in San Luis Obispo County, which could send 100-car oil trains through the densely populated portions of Los Angeles and the Bay Area.
The exponential growth and several accidents in the last half year, including one in Quebec that killed 47 residents in July, has prompted the NTSB to examine potential safety hazards, said Robert Sumwalt, an NTSB board member who is one of those overseeing the investigation. Sumwalt said that the agency should have started the review after a similar crash in Alabama in November, but that it was now focused on finding ways to reduce risks.
"It has certainly raised our attention and we want to make sure that people living in communities surrounded by railroad traffic are safe," he said.
Former NTSB Chairman Jim Hall said a comprehensive review of national policy on carrying crude was long overdue.
"It appears this is going to be in our nation's communities for the next decade," Hall said. "With this kind of transportation of hazardous material, there are a whole lot of issues that come to mind, not the least of which is terrorism. You are creating a movable bomb from community to community."
The string of rail accidents raises issues similar to those that came out of the Exxon Valdez spill in 1989, which prompted the National Research Council to conduct a broad public policy review, said USC safety expert Najmedin Meshkati. Such a review should have started "on the day after the Quebec accident," he said.
The safety alert issued Thursday by the federal Pipeline and Hazardous Materials Safety Administration warned that oil from North Dakota's Bakken shale fields "may be more flammable than traditional heavy crude." The agency said it would conduct new testing to determine the gas content, corrosivity, toxicity and flammability of the Bakken crude. The agency, which also regulates tank car safety, said it issued the alert to remind railroads that they are required to properly label the crude, based on three levels of volatility. The North Dakota shipment was already listed as the most volatile.
In the accident this week near Casselton, on a cloudy day with the temperature below zero, an eastbound train with 105 tank cars full of crude from the Bakken oil fields slammed into a westbound grain train that had derailed less than a minute earlier.
The grain train derailed while it was crossing over a switch at 28 mph. Sumwalt said investigators had found a broken axle from the grain train, though they were trying to determine whether it caused the accident.
A single car from the grain train ended up on the eastbound tracks and was struck by the oil train traveling about 42 mph. The two locomotives pulling the oil train were destroyed.
The accident occurred about a mile west of the town, which has a population of about 2,500.
Elsewhere in the country, "you have rail going through densely populated areas, and that is inherently risky," said Brigham McCown, former chief of the Pipeline and Hazardous Materials Safety Administration.
"The oil is going to get to market any way it can. I favor pipelines. They are buried, out of the way, safer and cheaper," he said.
Pipeline construction, however, has been sharply opposed by environmental groups. The proposed Keystone XL pipeline from Canada that would serve the Bakken fields has been tied up in a lengthy review by the U.S. State Department. Environmental activists believe that by blocking the pipeline they can restrict the development of the tar-sands oil fields in Alberta.
Sumwalt said the NTSB would be searching for ways to improve safety, but one of the most obvious possibilities would be for the Pipeline and Hazardous Materials Safety Administration to adopt an earlier NTSB recommendation for more resilient tank cars. The safety administration began considering strengthening its rules after the deadly accident in Lac-Megantic, Quebec. The accident this week did not result in any deaths or injuries, but it has heightened awareness of the danger.
Bill Keppen, a former Burlington Northern safety expert who is now an independent consultant, said one of the most important things for the federal government to address is human error, which accounts for about 44% of rail accidents. Keppen said he would expect the railroad industry to strongly oppose any attempt to reduce speeds of trains carrying hazardous materials. Railroads are free to set their own speed limits.
"Velocity is directly proportional to earnings and profits," Keppen said. "A small change in speed can translate to millions of dollars of profit a year."
Railroads do not currently have special requirements for training crews carrying hazardous materials, including crude oil.