NWT RESEARCH DATABASE

Tags: contaminants, water quality, metals, organic matter, sediment

Objective(s): To identify, quantify, and predict mobility of natural-source and legacy mine-source metals in soil, wetlands, and lake sediments that extend from former, present, and planned mine sites currently and as climate change alters the quantity and quality of dissolved organic matter.

Project Description: The seven-year objective of Sub-Arctic Metal Mobility Study (SAMMS) is to identify, quantify, and predict mobility of natural-source and legacy mine-source metals in soil, wetlands, and lake sediments that extend from former, present, and planned mine sites currently and as climate change alters the quantity and quality of dissolved organic matter produced and exported in subarctic NWT watersheds. During the first three years of SAMMS, the research team will quantify the current and future mobility of legacy atmospheric-source contaminants, above naturally occurring levels, from Giant Mine along a 200 km transect northwest of Yellowknife. Lake sediment cores will be obtained with a hammer-driven gravity corer from the floats of a helicopter. Sediment cores will be sectioned at 0.5 cm intervals. Lake sediment samples will be subjected to radiometric, physical, geochemical, and metals analyses. Lake water samples will be obtained for chemistry and metals analysis. In selected lake catchments, soil/wetland cores will be collected and analyzed for physical properties and metal concentrations. Water samples will be collected along flow pathways for chemistry and metals analysis. All samples will be transported to Wilfrid Laurier University and stored at 4C prior to analysis. Laboratory analyses will take place at Wilfrid Laurier University, University of Waterloo, and commercial labs. The research team will explore opportunities to provide training in the sampling techniques for local peoples, as the team have previously done in collaboration with the Marian Watershed Stewardship Program (MWSP). Findings will inform improved decision-making by multiple stakeholders in the NWT, including Indigenous peoples, about the legacy of mining activities and implications of new mining developments on water quality. SAMMS builds upon collaborative research the team have conducted with the Tlicho Government’s Marian Watershed Stewardship Program. The team will continue the practice of providing research updates at the annual MWSP Results Workshop. The research team issued an inaugural SAMMS newsletter to the partners in February 2018, and will continue to provide these periodically. During a recent trip to Yellowknife in February, a team member met with GNWT staff (Environment and Natural Resources, Health and Social Services) and members of the Giant Mine Oversight Board to relay the rationale, objectives, and research plan for SAMMS. A presentation about SAMMS at Sir John Franklin High School. The research team will continue to use field sampling visits to also communicate SAMMS research progress with interested individuals and communities. The fieldwork for this study will be conducted from June 28, 2018 to August 31, 2018.