Investigating the biogeochemical evolution of mature fine tailings associated with end pit lakes in the Alberta oil sands

为提取沥青而加工油砂会产生大量的矿山废物（例如水、淤泥/粘土、残余沥青、金属和残余溶剂）。目前的做法是重力沉降，然后储存在大型盆地中。然后将较致密的沉降产物（成熟的细粒尾矿MFT）转移到坑中。在Fort McMurray地区的设施中，一项正在进行的可持续战略是通过将采空区（例如West in Pit）合并为一系列终端池湖泊来创建一个遏制区域。当前的储存实践可以通过几种不同的机制影响周围环境。例如，在大量MFT中可能发生一些过程，这些过程将影响最终基矿湖泊中水帽的体积和质量。这包括由还原-氧化（氧化还原）介导的反应驱动的溶解成分水平的生物和化学变化，以及随着时间的推移，尾矿层的一般固结。拟议的研究计划将调查艾伯塔省Fort McMurray的Syncrude和Suncor油砂租赁作业中MFT的生物地球化学和氧化还原梯度的发展。这些信息将用于促进和支持目前正在开发的泥沙需氧量（SOD）环境模型，用于端坑湖的设计和实施。该研究项目将包括来自加拿大辛克鲁德有限公司、森科尔能源公司和累积环境管理协会（CEMA）的科学家，他们将为一名博士后、两名博士和一名硕士提供资金。还有三个本科生。该项目中的所有HQP将获得多学科经验，包括油砂开采和加工、尾坑湖修复、地球化学和电化学、分子微生物鉴定（使用新型T-RFLP分析和qPCR），以研究新加工和储存的MFT在尾坑湖填海中的长期行为。

Processing oil sands for the extraction of bitumen produces large volumes of mine waste products (e.g. water, silt/clays, residual bitumen, metals and residual solvents). The current waste practice is gravity settling and subsequent storage in large basins. The denser settled product (mature fine tailings MFT) is then transferred into pits. At the facility in the Fort McMurray region, an ongoing sustainable strategy is creating a containment region by combining the mined-out pits, (e.g. West In Pit) into a series of endpit lakes. The current storage practice can affect the surrounding environment via several different mechanisms. For example, a number of processes can occur within bulk MFT that will affect both the volume and quality of the water cap in the final base mine lakes. These include both biological and chemical alterations of dissolved constituent levels driven by reduction-oxidation (REDOX) mediated reactions, and general consolidation of the tailings layer over time. The proposed research program will investigate the biogeochemistry and development of REDOX gradients of MFT at Syncrude and Suncor oil sand lease operations in Fort McMurray, Alberta. This information will be used to facilitate and support sediment oxygen demand (SOD) environmental models currently being developed for end pit lake design and implementation. The research program will involve scientists from Syncrude Canada Ltd, Suncor Energy, and the Cumulative Environmental Management Association (CEMA) providing funding for one postdoctoral fellow, two Ph.D., one MSc. and three undergraduate students. All HQP in this program will gain multidisciplinary experience encompassing aspects of oil sands mining and processing, end pit lake remediation, geochemistry, and electrochemistry, molecular microbial identification (using novel T-RFLP analysis and qPCR) to investigate the long term behaviour of freshly processed and stored MFT in end pit lake reclamation.