Microbiological and geotechnical characterization of oil sands tailings in relation to acid rock drainage

• Main Author: Dean, Courtney
• Language: English
• Published: University of British Columbia 2015
• Online Access: http://hdl.handle.net/2429/51904

Traditional disposal of oil sands fine tailings has been a challenge to the industry, and developing new disposal technologies, such as surface deposition, poses alternative challenges. Unsaturated surface deposits of paraffinic froth treatment (TSRU) tailings have the potential to generate acid rock drainage (ARD). To develop environmentally-sound prevention measures to mitigate this risk, such as phage therapy, knowledge of the microbial and geotechnical characteristics of TSRU tailings is essential. To investigate the native microbial population potentially related to ARD generation in surface deposits of these tailings, enrichment cultures were used to isolate sulfur-oxidizing microbes at three stages of ARD development : pH 7, 4.5 and 2.5. Microbial growth studies were performed to establish the conditions for phage growth. The geotechnical properties and unsaturated behaviors were established of four variations of the tailings : untreated, polymer-amended, and two sand-mixed tailings. The findings indicate that TSRU tailings host native microbial communities potentially capable of playing a role in ARD development, and that the unsaturated tailings behavior would likely expedite this process upon surface deposition and subsequent desaturation. These results highlight the need for the development of ARD prevention technologies in the event of surface deposition of TSRU tailings. This research adds to the limited knowledge of microbial communities in oil sands tailings, and to the geotechnical performance of TSRU tailings. === Applied Science, Faculty of === Engineering, School of (Okanagan) === Graduate