Even though it was closed decades ago, the Giant Mine on the outskirts of Yellowknife has left a long environmental legacy.
The gold extraction process, which required roasting ores at extremely high temperatures, created a toxic byproduct called arsenic trioxide. For about 55 years (1948-2004), arsenic and other toxic elements were released into the environment, causing widespread contamination of the terrestrial and aquatic ecosystems around Yellowknife.
About 237,000 tonnes of arsenic trioxide dust is buried underground, and several nearby lakes show arsenic contamination.
Elevated arsenic levels have also been reported in soil, vegetation and fish around Yellowknife, but we knew little about how it has affected the health of the small mammals that live in the area.
Continue reading at University of Saskatchewan.
Image via flickr.