NWT RESEARCH DATABASE

Regions: Inuvialuit Settlement Region, Gwich'in Settlement Area

Tags: physical sciences, contaminants, water quality, hydrology, metals, groundwater

Objective(s): To investigate the environmental chemistry of the borrow pits and immediate surrounding areas to determine what, if any, environmental risk do the elevated concentrations represent; to investigate the environmental chemistry of an undisturbed area around the Inuvik to Tuktoyaktuk Highway (ITH) to see how it differs to that of the borrow pits (i.e. a control site); and, to determine the origin of, and main geochemical controls over, the elevated concentrations.

Project Description: This licence has been issued for the scientific research application No.4544. The objectives of this research are: 1) To investigate the environmental chemistry of the borrow pits and immediate surrounding areas to determine what, if any, environmental risk do the elevated concentrations represent; 2) To investigate the environmental chemistry of an undisturbed area around the Inuvik to Tuktoyaktuk Highway (ITH) to see how it differs to that of the borrow pits (i.e. a control site); and, 3) To determine the origin of, and main geochemical controls over, the elevated concentrations. Together, the research aims to clearly identify the main chemical process operating within this environment, thereby addressing the knowledge gap identified. The sites are not fully selected, but at each site there will be the same suite of data collected. Surface and groundwater samples will be taken on a detailed grid pattern at each site and throughout the active hydrological season. Groundwater samples will be taken via a new device currently under development that can withstand the annual feeze-thaw cycle. Sampling will be mostly via standard water collection methods (filtered at 0.45 microns into pre-cleaned HDPE bottles). There will be some ultrafiltration techniques deployed aimed at identifying colloidal phases. All water sampling will be accompanied by a complete suite of thermodynamic measurements (pH, ORP, Conductivity, Temperature). Samples will be analysed by CIP-MS and anion techniques at the Geological Survey of Canada's laboratories in Ottawa, Ontario. This data will define the annual chemical cycling that is occurring at each site. As the research matures, it is likely that there will need to be the deployment of more rapid analytical methods to identify discrete, but perhaps short duration, events within the sites. This will be done through collaboration with the Aurora Research Institute (ARI) in Inuvik, who have indicated that the team can access their laboratories for this purpose. ARI has also expressed an interest in such collaborations being used to build their chemical capabilities. These kinds of technology transfer/mentoring is well within the GSC's capabilities. At each site, wells and pits will be dug or augured to collect solid phase samples (e.g. ice, and organic soils). These will be analysed by sequential leach methods at the Geological Survey of Canada's laboratories in Ottawa, Ontario. This will identify what are the reservoirs of bioavailable versus lattice-bound elements within the matrices in the research areas. The hydrology at each site, especially the subsurface flow and surface-groundwater interactions, will be investigated via the water chemistry noted above, plus the use of hydrogen and oxygen isotopes. Hydraulic heads will be measured to determine potential flow rates. This data will define the basic hydrological cycles at each site. The PI has already visited community representatives in Inuvik to consult with their priorities. The Inuvik Hunters and Trappers Committee (IHTC) has expressed support for the project and wishes to be kept informed. This will happen on an annual basis, or more frequently if results warrant it. The Inuvialuit Regional Corp. also wish to be kept informed of the results, although how frequently is unclear. The NWT Department of infrastructure has also expressed support, as has the ARI. I will be irregular contact with each of these organisations as they will be important collaborators. The fieldwork for this study will be conducted from October 20, 2019 to December 31, 2019.