Assessment of Baseline Groundwater Physical and Geochemical Properties for the Quest Carbon Capture and Storage Project, Alberta, Canada

Abstract

Abstract The Shell Quest Carbon Capture and Storage (CCS) project will capture CO2 from the Scotford Upgrader Facility in Fort Saskatchewan, Alberta, Canada, and inject approximately 1 million tonnes of CO2 per annum over 25 years into the Basal Cambrian Sandstone aquifer. An MMV program has been designed and is being implemented. A key MMV component is the ongoing hydrological and geochemical monitoring of a number of groundwater wells. As part of the MMV process, this project has re-evaluated the shallow geology in the study area where necessary, and based upon this, defined four aquifers including the Surficial, Oldman, Foremost and Basal Belly River Sandstone (BBRS). Historic and ongoing groundwater monitoring data has been used to develop a hydrologic and geochemical baseline for the four target aquifers. Inferred regional groundwater flow directions and velocities have been calculated based upon the available hydraulic head, well pump test data and aquifer properties. Groundwaters from the Surficial, Oldman and Foremost aquifers cannot be separated based upon hydraulic head or upon aqueous chemistry. However, groundwater data from the BBRS aquifer suggests that the BBRS aquifer is hydraulically isolated from the overlying aquifers within the limits of the Quest Project Sequestration Lease Area (SQL). Based on the geochemical baseline, groundwater related solution chemical triggers are being defined which may be used to identity whether or not fluid and/or gas migration is occurring from the storage complex and, if that is the case, what impact those fluids and/or gas may have upon the potable groundwaters above the Base of Groundwater Protection (BGWP) across the SQL.