Tar Sands

What Are Tar Sands?

Tar Sands Open Pit Mine

Tar Sands Open Pit Mine, Alberta Canada

Tar sands (also referred to as “oil sands” or “heavy crude”) is made up of a thick petroleum sludge called bitumen, mixed with clay, water, and sand. This mixture is scraped or steamed out of vast deposits in Alberta, Canada, leaving behind a sprawling, toxic wasteland where boreal forests once stood. Because bitumen is so thick, it must be diluted with thin natural gas condensates- including the carcinogen benzene- before it will flow through a pipe. This mix of bitumen oil and chemical diluent is referred to “diluted bitumen” or dilbit for short.

Tar sands can be open-pit or strip mined and refined into oil. The Wisconsin Petroleum Council estimates that 80% of our gasoline comes from tar sands oil. Producing a barrel of tar sands oil is a more expensive and destructive process than drilling for conventional crude oil, and the process generates 22% more carbon dioxide emissions than conventional oil. Sadly, our efforts to drive more fuel efficient vehicles are significantly undercut by the lack of cleaner-burning fuels to put in our gas tanks here in the Great Lakes region.