The Northwest Territories (NWT) is rich in minerals including gold and uranium. As a result, many mines, active and abandoned, dot the landscape. Some have left a legacy of metal pollution.
The Sub-Arctic Metal Mobility Study (SAMMS) began in 2017 but traces its roots back to 2011, when Professor Brent Wolfe and some colleagues were invited to investigate whether pollutants from the Alberta oil sands industry might be reaching the Slave River Delta in the NWT. The researchers did not find evidence of oil sands contaminants – however, they found elevated levels of arsenic in sediments deposited in the 1950s. They concluded the arsenic likely came from the now-defunct Giant Mine near Yellowknife, meaning atmospheric emissions had travelled much farther than previously recognized.
Funded through Global Water Futures, SAMMS aims to understand how legacy pollutants from mining activity move through the landscape, with potential negative effects on drinking water and aquatic organisms.
Co-principal investigators Wolfe and Assistant Professor Jason Venkiteswaran are working with a multi-university team of researchers on an array of field, laboratory and modelling studies. Since metals tend to bind to organic material, the researchers aim to trace the transport and behaviour of dissolved organic matter and metals through terrestrial and aquatic ecosystems along a 200-kilometre stretch between the former Giant Mine site and Whatì, an area of concentrated mining activity.
Ultimately, SAMMS is designed to identify, quantify and predict the mobility of metals in soil, wetlands and lake sediment as climate change alters subarctic watersheds and their dissolved organic matter. Their work will help inform decision-making by governments and Indigenous communities about the legacies of mining activities and the implications of new mining developments on water quality in a changing environment.