http://www.wnyc.org/story/apocalyptic-endgame-tar-sand-oil-extraction/
“Mining petroleum from the Canadian tar sands is one of the most labor intensive extraction processes ever undertaken. Ted Genoways explains how tar sands mining is done and looks at its environmental and health consequences: http://www.outsideonline.com/outdoor-adventure/nature/The-High-Cost-of-Oil.html”