WASHINGTON Five years before a train loaded with crude oil derailed and exploded last year in Quebec, killing 47 people, another derailment in Oklahoma should have given federal regulators an early warning that the type of oil both trains carried was more flammable than authorities realized.
But little has been done to improve the safety of tens of thousands of railroad tank cars that have been pressed into service in recent years to haul large quantities of crude oil and ethanol.
The rail industry supports tougher safety requirements for new and existing tank cars, including thicker shells, puncture-resistant shields and stronger valve fittings to prevent spills and fires if the cars should derail. But new rules have been delayed amid concern about the estimated $1 billion cost of making the changes and the time it would take amid a surge in profitable shipments.
The Railway Supply Institute, an industry group, last month proposed a 10-year timeline for retrofitting the entire tanker fleet. A final decision from the Pipeline and Hazardous Materials Safety Administration on what steps to take is expected this year.
The delay has come even though fiery crashes as far back as 2006 have highlighted a safety issue that's growing as the U.S. oil boom drives skyrocketing growth in the use of railroad tankers to move crude oil across the country.
At least two derailments involving crude oil from the Bakken region of North Dakota and Montana have taken place in the past two months, one in Alabama in November and another in North Dakota this week. Bakken oil is a key ingredient in an American energy renaissance, and in the absence of new pipelines, rail has become the primary way to transport it.
On Monday, a BNSF Railway crude oil train derailed near Casselton, N.D., resulting in a massive fire and the temporary evacuation of two-thirds of the town's 2,500 residents in subzero temperatures. Crews are working to restore rail service to the area while the National Transportation Safety Board continues its investigation.
Compounding the worry over the tank cars is the composition of the crude they're carrying. The Pipeline and Hazardous Materials Safety Administration said Thursday that Bakken crude oil had a lower flash point than other forms of crude oil, meaning it's easier to form vapors that could ignite. The agency said the oil posed "significant fire risk" if released and warned that it needs careful handling.
The pipeline agency and the Federal Railroad Administration, which share responsibility for regulating such shipments, may have had prior indications that the oil posed unique hazards.
According to publicly available reports from both agencies, a BNSF Railway freight train that derailed in Luther, Okla., in August 2008, was carrying eight cars of crude from the Bakken region. The reports show that five of the derailed cars caught fire.
Local TV news footage available on YouTube shows black smoke pouring from the scene, in a rural area about 30 miles northeast of Oklahoma City. At one point, a large explosion sends a massive fireball hundreds of feet into the air.
No one was injured or killed in the derailment, which federal investigators blamed on a track defect. But spectacular derailments have become a familiar sight in recent years, and reports of the events compiled by federal rail and pipeline regulators share notable details, including the use of tank cars prone to catastrophic failures.
Many towns across North America, from New Brighton, Pa., to Columbus, Ohio, to Plevna, Mont., have had close calls in explosive train derailments in the past several years. But Lac-Megantic, Quebec, wasn't so lucky.
Canadian authorities haven't completed their investigation of the deadly July derailment of a Montreal, Maine & Atlantic Railway train that destroyed a large portion of the lakeside town and shattered the lives of those who survived the inferno.
Railroad officials initially blamed human error and noted the unusual combination of circumstances that led to the accident. But the 2008 derailment and at least two more in the past two months point to other factors.
Eight U.S. incidents involving DOT-111 tank cars in the seven years before Lac-Megantic could have warned federal regulators that the cars weren't up to the task.
The NTSB expressed concern about the integrity of the DOT-111 cars as far back as 1991, and regulators had proposed studying whether the fleet could be improved at least a decade before that.
Karen Darch, the village president of Barrington, Ill., a Chicago suburb, has called DOT-111s the "Ford Pinto" of railcars, comparing them to the 1970s automobile vulnerable to fire. She and other mayors have expressed alarm as more hazardous shipments move through their communities, sometimes within feet of homes, schools and businesses.
A 2012 NTSB report singled out the faults of the tank cars as a major factor in a June 2009 derailment in Cherry Valley, Ill. One woman was killed and several other people were injured, including two firefighters, when a Canadian National Railway ethanol train derailed and caught fire at a road crossing after heavy rains had washed out the track.
"The release of hazardous materials likely would have been significantly reduced, mitigating the severity of the accident," the NTSB concluded, had the DOT-111 tank cars been better able to resist puncture and rupture.
According to the Association of American Railroads, an industry group, railroads hauled 70 percent to 75 percent of the country's ethanol production in 2012. In 2010, 325,000 carloads of ethanol moved by rail, up from 40,000 a decade before.
The growth of crude oil shipments is even more staggering. Railroads handled 200,000 carloads of crude in 2012, up from 9,500 in 2008. In October, 70 percent of the oil produced in the Bakken region moved by train.
Rail has helped North Dakota become the nation's No. 2 oil producer, behind Texas. Alaska now ranks third.
The director of North Dakota's Department of Mineral Resources has predicted that rail's share of crude oil shipments might increase to 90 percent this year.
Darch said she visited Lac-Megantic last month with a group of mayors from Quebec and Maine. She said it was incredible to see the damage firsthand, and how quickly the town was moving to rebuild. But it also showed the cost of waiting to make rail safety improvements.
"Nothing will move until there's a crisis," she said. "The crisis was this summer."
U.S. officials acknowledge the problem, but say they think it's manageable.
"In 2008, petroleum crude oil had yet to be ranked even among the top quarter of hazmat commodities shipped by rail," said Kevin Thompson, a spokesman for the Federal Railroad Administration, "and although there has been exponential growth in the shipment of crude oil over the last three years, the number of accidents are still rare."
NTSB brief on 2011 Illinois derailment and fire
NTSB report on 2006 Pennsylvania derailment and fire
NTSB report on 2009 Illinois derailment and fire
Federal Railroad Administration report on 2008 Oklahoma derailment
YouTube video of 2008 Oklahoma derailment and fire
By Curtis Tate
McClatchy Washington Bureau