Image above: Fieldwork involves downloading data loggers installed in monitoring wells. However during the summer dragon fly accessories are also included..
Photo Credit: Michelle Barnes.
In areas impacted by permafrost, frozen ground is an impermeable barrier between the suprapermafrost and subpermafrost portions of the aquifer. Discontinuities in permafrost are areas of possible connection between these two main portions of the aquifer. In contaminated aquifers these areas of connection between the two portions of the aquifer influence the transport of contaminants necessitating the delineation of these discontinuities and the influence they have on the groundwater flow. Identifying the locations for discontinuities has previously been limited to evaluating well logs and the use of ground penetrating radar. A method focused on using tracers to identify areas of discontinuities in the permafrost would not only help locating thawed through-taliks, but may also improve our understanding of the interaction between the subpermafrost and suprapermafrost portions of a discontinuous permafrost aquifer. Understanding this is paramount to characterizing the transport of contaminants in these types of aquifers and may aid in the development of water supplies. In this study we use groundwater elevation trends and environmental tracers (e.g. stable isotopes and temperature) to delineate the location of discontinuities in a contaminated aquifer located in a region of discontinuous permafrost in the Interior of Alaska.
