HYDROGEOLOGY AND HYDROCHEMISTRY OF AN AQUIFER AQUITARD SYSTEM WITHIN GLACIAL DEPOSITS, SASKATCHEWAN, CANADA

The hydrology and hydrochemistry of an aquifer-aquitard system within glacial drift has been studied, utilizing data for the aquitard as well as the aquifer. The study area lies in the western glaciated plains near Saskatoon, Saskatchewan, Canada. Hydrological and chemical processes within the overlying till control the recharge rate, major-ion chemistry and isotopic composition of the water in the aquifer. The bedrock is hydraulically isolated from the system and does not affect the groundwater chemistry. Reaction products generated in the till are fed into the aquifer by advection and diffusion. The aquifer acts as a chemically inert lateral transmission and mixing zone. Hydrochemical patterns in the aquifer are regional in extent and appear to be related to the geochemical conditions within the till and the flow pattern in the aquifer. The system is evolving geochemically on a time scale of thousands of years.