Dirty Oil

By Katherine Bourzac

Description text

About 80 percent of Alberta's oil sand is too far below the surface to dig up. The most common method for getting the bitumen out is through two parallel horizontal wells lined with perforated pipe. Heat from high- temperature steam injected down one of the wells softens surrounding bitumen--which in oil sand form normally flows about as easily as Crisco--causing it to separate from the sand and flow down into the second well, from which it is pumped to the surface.