Environmental advocacy group Sierra Club said the United States will import more than 1.5 million barrels of tar sands oil from Canada by 2020, a 10 percent increase over current levels.
Michael Marx, a campaign director at the Sierra Club, said the group was concerned about the expected rise in Canadian crude oil imports.
"We've got all this unconventional crude and we're completely unprepared for it," he told CNN Money.
Sierra Club and other environmental groups say Canadian crude is more harmful to the environment than conventional oil. It's also more corrosive, meaning pipelines carrying Canadian oil could be prone to leaks.
It sinks in water, adds Marx, meaning U.S. responders "don't have the technical sophistication to vacuum oil off the bottom of a river."
Several tar sands pipelines, including the Keystone XL, are in various stages of construction or planning in the United States.
Andy Black, president of the Association of Oil Pipe Lines, told CNN the industry was prepared for the rush, however.
"No pipeline operator would want to spend billions of dollars to transport something their pipeline can't handle," he said.
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