As the world’s demand for metals continues to rise, some are using microorganisms to mine and “clean” waste.
When Nadia Mykytczuk first visited the mine sites near Copper Cliff, on the outskirts of Greater Sudbury, Ontario, in 2005, she saw rock piles stretching out in all directions—not so much dotting the landscape as forming their own. On first impression, says Mykytczuk, “you really can’t quite comprehend that everything you see around you is mine waste.” Some of that rubble is what is known as tailings—the crushed rock or wet slurry left behind after a company has extracted raw materials from ore. But to Mykytczuk, then a PhD student, those drab rock heaps looked a lot shinier.
(Celina Gallardo / iStock)
Each year, Canada’s approximately 200 active mines contribute to the billions of tonnes of mining waste already accumulated in the country; that waste is then typically contained in pits or stored underground or in dams. While estimates vary wildly, there are thought to be anywhere between 1,800 and 8,500 tailing facilities worldwide. Many of them still contain some metals but at a concentration that for a long time was deemed too low to be worth extracting. So the discards mostly lie there, untouched, until someone finds another use for them. Which is what Mykytczuk has been working on over the past two decades.