ENVIRONMENT

It wasn’t much of a bouquet—just a single lonely dandelion. But it had been plucked from the middle of a barren stretch of polluted oil sands. Researchers knew right away that made it something special. (Canadian Press)

What are oil sands? What’s going on with oil sands in Canada? Get the scoop on this Geography in the News.

Discussion Ideas

• The Globe and Mail article says the presence of a lonely dandelion in the “middle of a barren stretch of oilsands coarse tailings” sparked the interest of a local biologist. What are oil sands? What are coarse tailings? Take a look at our encyclopedic entry section “Petroleum and the Environment: Bitumen and the Boreal Forest” for some help.
  • Oil sands, also known as tar sands, describe a geologic area that contains sand, clay, and a thick, sticky form of crude petroleum called bitumen. In its natural state, bitumen is extremely difficult to extract and an unconventional source of oil. Processing bitumen from tar sands is a complex, expensive procedure; it takes two tons of oil sands to produce one barrel of oil.
  • Tailings describe residue or material left over from a mining process, after valuable minerals (in this case, hydrocarbons) have been extracted. Coarse tailings describe large particles that settle out of water that has been used to separate oil from raw bitumen.
    • According to Oil Sands magazine, tailings ponds like the one where the dandelion was found are “massive earth structures used to store coarse and fine solids contained in the oil sands deposit … These ponds are temporary storage facilities and need to be reclaimed when no longer in use. Fine solids from tailings streams tend to trap large volumes of water, making pond reclamation challenging at best.” Read through their Tailings Ponds 101 for more information.

 

• Why was that lonely Canadian dandelion so intriguing to biologists?
  • Oil sands tailings contain mining residues that are often toxic to indigenous plants. These residues are still being studied, but contain acids, salts, and other chemicals that create an extreme environment.

 

• How did the humble dandelion become an extremophile?
  • It didn’t do it alone! There was a fungus among us. According to the Canadian Press, “The dandelion was hosting a symbiotic fungus that was literally eating what the miners had left behind” and converting it into carbon dioxide and water.

 

• How have biologists and ecologists tested the fungus found on the dandelion?
  • Scientists treated tomato and wheat seedlings with the fungus, and planted them in coarse tailings. According to the Canadian Press, “Standard remediation seed mixes almost completely failed to germinate when planted in tailings. Treated with the fungus, 90 per cent of the seeds germinated.” (Wow!)

 

• What challenges remain for scientists seeking to restore the natural oil sands ecosystems?
  • scale. The fungus shows great promise in helping clean up coarse tailings, but there are 800 square kilometers (309 square miles) of coarse tailings in the region.
  • fine tailings. The fungus does not impact fine tailings, the tiny particles of silt and clay that remain suspended in 1.3 trillion liters (343 million gallons) of water in giant tailings ponds.

 

TEACHERS TOOLKIT

The Globe and Mail: Dandelions found in oil sands tailings could help clean them up: researchers

Nat Geo: Keystone Pipeline and Canadian Tar Sands

Nat Geo: What is Petroleum? (section: “Petroleum and the Environment: Bitumen and the Boreal Forest”)

Oil Sands Magazine: Tailings Ponds 101