FILE - In this Wednesday, Feb. 1, 2012 file photo, miles of pipe ready to become part of the Keystone Pipeline are stacked in a field near Ripley, Okla. President Barack Obama says that the proposed

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FILE - In this Wednesday, Feb. 1, 2012 file photo, miles of pipe ready to become part of the Keystone Pipeline are stacked in a field near Ripley, Okla. President Barack Obama says that the proposed Keystone XL pipeline project from Canada to Texas should only be approved if it doesn't worsen carbon pollution. Obama says allowing the oil pipeline to be built requires a finding that doing so is in the nation's interest. He says that means determining that the pipeline does not contribute and "significantly exacerbate" emissions. (AP Photo/Sue Ogrocki, File) less 

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Associated Press
Tue, Jun 25, 2013 11:48 PM EDT