Jim Prentice, the premier of Alberta, Canada, says the fight over the Keystone XL pipeline has been a long and tortured process. But, he adds, if President Obama vetoes a bill that would approve construction, the issue will not necessarily go away.

There is enormous opposition among environmentalists to the $8 billion pipeline project that's designed to bring crude oil extracted from the Canadian tar sands to refineries along America's Gulf Coast.

Environmentalists on both sides of the border say extracting the thick crude oil is scarring Northern Alberta's landscape, and there are concerns about oil spills. The tar sands are also part of a larger debate about climate change, with opponents claiming the extraction process increases greenhouse gases.

A report released by the Environmental Protection Agency on Monday says, "Over the 50-year lifetime of the pipeline, this could translate into releasing as much as 1.37 billion more tons of greenhouse gases into the atmosphere."

Prentice is in Washington, D.C., to counter those concerns and to lobby Congress and the administration for the go-ahead on the pipeline. In an interview with NPR's David Greene, he says Alberta "has the most exacting standards around in terms of carbon emissions, the regulatory framework that surrounds industrial emissions." He says Alberta has taken steps to control venting and flaring of methane. "In all these areas, I think we're world-class."

Prentice's comments come as Republican leaders announce that the House will vote final approval next week on legislation that would clear the way for construction of the pipeline. Obama has threatened to veto any bill approving the pipeline.

Prentice says the fight over Keystone has become a symbolic issue "in terms of the exercise of authority by the president versus the Congress."

Prentice, a former environment minister, says Alberta is Canada's largest supplier of oil, exporting 2.5 million barrels per day. He says crude will continue to be transported to the U.S., whether it's by pipeline or rail car.

Alberta's tar sands have transformed the prairie province over the past 15 years. New, expensive projects aimed at extracting the roughly 160 billion barrels of reserves from the ground have provided jobs to thousands of people. But plummeting oil prices are having an effect. The New York Times reports several companies are reducing their workforce, including Suncor, the largest oil sands operator, which says 1,000 contract jobs will be eliminated. The newspaper says Shell Canada will cut its oil sands workforce by about 10 percent, and Cenovus Energy will cut investment spending by more than a quarter.

Prentice says despite a lack of project expansion, oil sands production will increase by over 300,000 barrels per day because capital investments are already locked into place and it's too difficult to shut the projects down. There's also a concern about losing valuable market share.

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