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. Co-op students from Yukon College, Whitehorse and from Aurora College, Inuvik will assist with summer field work as well as with year-round sampling. Students will be trained on advanced analytical methods in our new CFI/OIF-funded environmental isotope sciences facilities, including noble gases, radioisotopes by AMS, and tritium. Success of the program relies on the participation of northerners from local communities and school children for assistance with fall and winter monitoring.