Field Work in Permafrost Hydrogeology

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Over the past two decades, my students and I have examined the role of groundwater in permafrost terrain, from biomineralization and methanogenesis to ground-ice and river icings. We have demonstrated the importance of water movement through permafrost and its role in catchment hydrology, salmon spawning, ecosystem functioning and water resources. The documented increase in permafrost temperatures potentially enhances the expansion of talik and contribution of groundwater to permafrost hydrology. There are significant implications of enhanced groundwater movement, ranging from heat flux and permafrost stability to solute transport and contaminant migration. Over the next five years, we will focus on understanding the mechanics of groundwater recharge and movement in permafrost on two different scales. One is the watershed scale, comprising groundwater flow through intra-permafrost talik and active layer drainage and its role in nutrient cycling and energy fluxes at a series of monitored permafrost watersheds. The second is in the characterization of ice-bonded sediments as aquitards - low permeability materials that restrict groundwater movement. With increased development in the north, and with the reliance of permafrost as a barrier to contaminant migration (drilling sumps, community waste lagoons, tailings), permafrost aquitards have become an important component of arctic hydrology. The proposed research program will involve field sites in the Yukon and NWT, most of which are accessible from Whitehorse, along the Dempster Highway and by helicopter support from Polar Shelf from Inuvik. Students spend on average 4 weeks in the field, often with multiple trips to gain access at diferent times in the melt season and during freeze-up. Field support is required for the costs of travel (air, truck, boat), deploying camps,visiting communities for outreach and knowledge transfer, and for engaging Yukon College and Aurora College Co-op students as field assistants, contributions to their programs and for off-season sampling.