There’s a good chance you’ve heard about the Canadian tar sands if you’ve been following the debate on the Keystone XL pipeline. But what exactly is tar sands oil? And how is it different from conventional oil? The facts might surprise you.
Let’s start at the beginning — where does tar sands oil come from?
The tar sands region spans about 55,000 square miles in northeast Alberta, Canada. To put this in perspective, we’re talking the size of Florida.
Now you might be picturing a tar sands wasteland, but the reserves actually lie beneath Alberta’s Boreal Forest and wetlands, one of the largest remaining ecosystems on earth.
The tar sands make up the bulk of Alberta’s proven oil reserves, which are the third largest in the world behind Saudi Arabia and Venezuela. These “proven reserves” contain 168 billion barrels of tar sands oil (this is the amount that can be extracted at a profit using today’s technology). But the total reserves contain an estimated 1.8 trillion barrels and as technology improves, more and more of this reserve is expected to become accessible.
What exactly is tar sands oil? A mixture of sand, clay, water and bitumen — an extremely heavy, thick and sticky oil that has the consistency of molasses. Unlike conventional oil, bitumen is too thick to be pumped from the ground — it must be either mined or extracted by injecting steam into the ground.
Before it can flow through pipelines, the bitumen must be mixed with a cocktail of chemicals to give it a similar consistency to conventional crude oil. The result is something called “dilbit” — a mixture of bitumen and these diluting chemicals. We don’t know what exactly is in dilbit because the oil companies aren’t required to disclose what chemicals they use to make it — but we do know that the mixture often includes benzene, a known human carcinogen.
Tar sands is not your typical oil — it’s dirtier and it’s more dangerous.
Subscribe to our Tar Sands Crash Course, we’ll explore the unique challenges and risks associated with tar sands at every stage of the process: extracting, transporting and refining.
Next week, we’ll take a closer look at how oil companies get at this crude, and the impact of the process on local communities.