It would appear that Canada is sitting on immense wealth. Sadly the down side is the could become one of the world's greatest polluters.

Alberta, Canada's oil sands are the largest known reserve of oil on earth, containing between 1.7 and 2.5 trillion barrels. (Saudi Arabia, by comparison, has only 262 billion barrels of proven reserves. In fact, all OPEC nations combined have less than 900 billion barrels.)

For decades, these sands weren't even considered part of the world's oil reserves because the oil there wasn't economically extractable at prevailing prices using then-current technology.

But times have changed… And the gold rush is on.

In Alberta's oil sands, energy companies don't drill for oil. They dig it up. After excavation, giant trucks three stories high - carrying up to 400 tons of oil sands - carry it off to a processing plant. There, the sands are heated in a cell where the oil comes to the top of the water and the sand drops to the bottom. This oil froth is then sent to an upgrader and eventually to a refiner.