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

加工油砂以提取沥青会产生大量的矿山废物(如水、淤泥/粘土、残留沥青、金属和残留溶剂)。目前的废物做法是重力沉降，然后在大盆地中储存。然后将较稠密的沉淀物(成熟的细粒尾矿)转移到矿坑中。在麦克默里堡地区的设施，一项正在进行的可持续战略是通过将采空坑(例如西坑)合并为一系列尾坑湖泊来创建遏制区域。当前的存储做法可能会通过几种不同的机制影响周围环境。例如，在散装MFT中可能会发生许多过程，这些过程将影响最终基地矿湖中的水帽的体积和质量。这些变化包括还原-氧化(氧化还原)反应引起的溶解成分水平的生物和化学变化，以及尾矿层随时间的普遍固结。拟议的研究计划将在艾伯塔省麦克默里堡的辛克鲁德和森科尔油砂租赁业务中调查MFT的生物地球化学和氧化还原梯度的开发。这些信息将用于促进和支持目前正在为末端坑湖设计和实施而开发的沉积物需氧量(SOD)环境模型。该研究计划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，为一名博士后研究员、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都将获得多学科经验，包括油砂开采和加工、尾矿坑湖泊修复、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)，以调查新加工和储存的MFT在尾矿坑湖泊复垦中的长期行为。

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.