The Suncor tar sands mining operation north of Fort McMurray, Alberta, is shown in this November 3, 2011 file photo. Suncor said it was slowing down its oil sands operations after a TransCanada Corp ... more 
The Suncor tar sands mining operation north of Fort McMurray, Alberta, is shown in this November 3, 2011 file photo. Suncor said it was slowing down its oil sands operations after a TransCanada Corp natural pipeline break forced some of the Canadian oils sands biggest producers to cut back their output on October 17, 2013. REUTERS/Todd Korol/Files (CANADA - Tags: BUSINESS ENERGY) less 
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Reuters | Photo By TODD KOROL / REUTERS
Fri, Oct 18, 2013 12:13 PM EDT