PORTLAND, Maine (AP) - Railroad cars filled with crude oil from the Bakken oil field of North Dakota are crossing Maine in unprecedented numbers bound for an oil refinery in Canada.
Trains carried nearly 5.3 million barrels of crude across Maine to New Brunswick last year, and officials say the volume is growing.
It's the same story across the country. The Association of American Railroads says U.S. trains last year carried nearly 234,000 carloads of oil, a 256 percent jump from 2011.
The growing volume of oil is raising concern among environmentalists and government officials about the threat of an accident and spill, but railroads say moving oil by train is perfectly safe.
One train derailed this month in Mattawamkeag near the Penobscot River, though only a tiny amount of oil spilled.
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