Tom Giesen writes in a guest column for Informed Comment
The US already imports over 2.5 million barrels of Canadian oil each day. Much of it is tar sands oil. The proposed Keystone XL pipeline in the US for tar sands oil is a huge and irreversible mistake.
Tar sands processes have contaminated huge quantities of water, poisoned downstream communities, and destroyed incomparable ecosystems, replacing them with toxic waste dumps.
Alberta’s tar sands produce the dirtiest oil on the planet. The tar sands stretch across a huge area in Alberta’s boreal forests.
The process of getting oil from tar sands is destructive, hugely polluting, and expensive. Here is what is involved:
To access the near-surface tar sand, the boreal vegetation is clear-cut logged and/or stripped off, the covering soils dug up and hauled off, and the exposed tar sand – a mix of bitumen, sand and clay – is strip-mined and transported to a processing plant. It takes more than two and a half tons of tar sands to make one barrel of oil.
In processing, the tar sands are mixed with river water (making the water toxic); then dumped in a separator and heated to induce the bitumen to float to the top.
The floating bitumen is then skimmed off, and the remaining highly toxic wastes – non-floating bitumen, sand, clay and water – are taken to ponds in the open pit mining area and dumped. Birds beware!
The thick bitumen from the separator is mixed with lighter hydrocarbons so it can be pumped and then refined into a heavy crude oil.
The carbon dioxide emissions caused by the multiple processes are more than 20% greater than those from normal crude oil. Tar sands emissions are nearly as bad as coal.
The only thing more toxic than tar sands waste ponds is the thinking that allowed them to be created.
Ed. note: for more on the campaign to stop Keystone XL see:
“Bill McKibben pushes Obama on Keystone”