Nature and Origin of Pristine Groundwater in Confined Glacial Aquifers in the Simcoe Lowland, Ontario

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This project concerns a study of groundwater in sand/ gravel aquifers in part of Simcoe County ON, centred around the Village of Elmvale, 10 km east of Georgian Bay. Groundwater in this area has exceptional characteristics, most notably, many flowing artesian wells at depths between 15 and 70 m. Most of these wells yield water that is fresh, potable and pristine, meaning that there are no chemical constituents in the water derived from human activities including agriculture (i.e. no anthropogenic chemicals), and only very low trace elements. Fresh pristine groundwater is extremely rare in Canada and elsewhere. This study is aimed at determining origins and chemical characteristics of such anthropogenically pristine water and of the other water in the aquifers in the area. One possibility is that the pristine water is in part remnant glacial-age water many thousands of years old, so an objective will be to estimate how many decades will pass before the pristine water disappears, replaced by new younger-aged groundwater. The pristine groundwater is discharging from flowing artesian wells, groundwater is pumped from many other wells in serving the rural population and Elmvale. The aquifers are replenished by infiltration from rainfall and snowmelt in an upland forested area of sand and gravel deposits within a few km of the artesian area. Another possibility for the pristine groundwater is that it is not glacial age but acquires its pristine characteristics by purification processes as it flows in the ground. This study will assess these two possibilities. This project will apply new types of devices, one of which has a patent application submitted in October 2018, to be installed in drill holes for sampling and for monitoring pressure and temperature distribution in the groundwater. These devices will provide, at relatively low cost, much more information than conventional monitoring wells. In addition to answering questions about origin of the rare type of groundwater in Elmvale area, this study will provide an assessment of the value of this new approach to groundwater monitoring. This is important because generally groundwater in Canada and the world at large is poorly monitored, which severely limits prospects for science- based groundwater management. The Elmvale area is most appropriate for this study because other researchers have previously conducted other types of related investigations that serve well to set the stage for this proposed work.