The U.S. State Department issued a permit Thursday allowing construction of a pipeline that will bring crude oil to the U.S. from Canada's oil sands, where environmental groups say extraction and refinement methods are contributing to global warming.
With the permit in hand, Enbridge Inc. plans to start construction work on the Alberta Clipper pipeline, which will run through Minnesota and the northeastern corner of North Dakota from Superior, Wis., to Hardisty, Alberta.
In a statement announcing the permit, the State Department called Canada a "stable and reliable ally" and said increasing capacity for Canadian crude oil to reach the U.S. will "advance a number of strategic interests of the United States."
Environmental groups had urged Secretary of State Hillary Clinton to reject the permit, saying extracting and refining crude from Canada's oil sands emits high amounts of greenhouse gases and threatens the water and air.
A coalition of environmental and Native American organizations vowed Thursday to challenge the permit in court, expressing disappointment with President Barack Obama's administration.
"Both Obama and Hillary Clinton who had to sign off on this permit campaigned on reducing our reliance on oil and moving to a cleaner and greener energy system. This will be a step backward," said Chuck Laszewski, spokesman for the Minnesota Center for Environmental Advocacy, which is part of the coalition.
Environmentalists say crude extracted from oil sands produces more greenhouse gases than other sources, partly because it requires a more intensive refining process before it can be used. In Canada, extracting the oil leaves behind toxic residue and damaged lands, said Sarah Burt, an attorney for Earthjustice based in Oakland, Calif.
"We are committing to import huge amounts of this oil. It's the most toxic type of oil that there is," Burt said.
The State Department said it considered environmental concerns — including greenhouse gas emissions — in its review, but said emissions reductions are best addressed through domestic policies in each country and a strong international agreement.