Hydrogeology of the Swan Hills Area, Alberta: Evaluation for deep waste injection

A detailed hydrogeological study was carried out in a region defined as Tp 62-74 R 1-13 W5M, comprising 15 760 square km effectively centered on the Special Waste Injection Site of the Alberta Special Waste Management Corporation. The objective was the selection of aquifers for environmentally safe disposal of waste water from treatment processes. The approach included: (1) identification of the major hydrogeological and economic constraints; (2) analysis of the natural flow system for all hydrostratigraphic units between the Lower Cretaceous Viking aquifer and the Precambrian basement; (3) numerical simulation of the flow in, effectively, the entire Phanerozoic succession to obtain conformance with the natural flow system; and (4) steady-state perturbation of the system at an injection rate of 225 cubic meters/d in two potential injection aquifers to evaluate the importance of the hydraulic head buildups at a theoretically infinite time of injection. The study was based on examination and interpretation of stratigraphic information from 3276 wells, and on 635 drillstem tests, 3477 core analyses, and 645 formation water analyses, all from the files of the Energy Resources Conservation Board, using specialized software developed by the Basin Analysis Group, and the three-dimensional finite element groundwater model FE3DGW. The preferred injection aquifer is the basal portion of the Wabamun-Winterburn aquifer system. The Basal Cambrian aquifer was selected as a less desirable backup injection aquifer. After completing this study, a well was drilled to the top of the Ireton aquitard and successfully tested and completed in the Wabamun-Winterburn aquifer system.