BILLINGS, Mont. — At least 10 times since 2008, freight trains hauling oil across North America have derailed and spilled significant quantities of crude, with most of the accidents touching off fires or explosions.
The derailments released almost 3 million gallons of oil, nearly twice as much as the largest pipeline spill in the United States since at least 1986. And the deadliest wreck killed 47 people in the town of Lac-Megantic, Quebec.
Those findings, from a review of US and Canadian accident records, underscore a lesser-known danger of America’s oil boom, which is changing the global energy balance and raising urgent safety questions closer to home.
Experts say recent efforts to improve the safety of oil shipments have not eliminated an unsettling fact: With increasing volumes of crude moving by rail, it has become impossible to send oil-hauling trains to refineries without passing major population centers, where more lives and property are at risk.
Adding to the danger is the high volatility of the light, sweet crude from the Bakken oil patch in Montana and North Dakota, where many of the trains originate.
Because it contains more natural gas than heavier crude, Bakken oil can have a lower ignition point. Of the six oil trains that derailed and caught fire since 2008, four came from the Bakken and each caused at least one explosion. That includes the accident at Lac-Megantic, which spilled an estimated 1.6 million gallons and set off a blast that levelled a large section of the town.
After recent fiery derailments in Quebec, Alabama, North Dakota, and New Brunswick, companies and regulators in the United States and Canada are pursuing an array of potential changes such as slowing or rerouting trains, upgrading rupture-prone tank cars, and bolstering fire departments.