Northwest Territories Geological Survey

Giant Mine, located in Yellowknife NWT, released a large amount of arsenic and other metals during the initial phase of its operation. These contaminants were then deposited on the landscape. Recent paleolimnological evidence has suggested that the pollution dispersed more than 100 km from the source. The landscape surrounding Yellowknife, like many subarctic systems, is dominated by peatlands with large quantities of organic matter that has built up over millennia. Peat and other forms of organic carbon can play important roles in the sequestration and mobility of arsenic, yet little is known about what controls these processes. Understanding these controls is important to anticipate the consequences of climate change on the release of pollutants to downstream ecosystems. Based on current paleolimnological research along an 80-km transect northwest of Yellowknife (see poster by Jasiak et al.), peat cores will be collected from locations of known arsenic pollution. The objectives of this project are to: (1) measure the concentration of metals in peat core samples and characterize the role of peat as a repository of metals, and (2) perform experimental manipulations that mimic wet-dry cycles and fire events to determine if these processes influence metal mobility within peat profiles. This research will provide insight into the potential hazard that remobilized metals pose to ecosystems.