Understanding impacts of microbial methane ebullition in oil sands pit lakes: methane release and transport of petroleum hydrocarbons

艾伯塔省油砂地区的石油是加拿大经济的关键组成部分。目前，对AOSR露天采矿作业影响的土地和产生的尾矿进行复垦是加拿大的一项核心产业和环境优先事项。加拿大辛克鲁德有限公司于2012年通过开发一个8平方公里的坑湖(PL)基矿湖(BML)，委托采用水封尾矿技术(WCTT)进行油砂复垦的首个范例。虽然在硬岩采矿中，PL回收通常用于尾矿管理，但由于尾矿具有丰富的有机特性，AOSR是独一无二的。自2012年以来，辛克鲁德一直支持一项旨在了解BML发展的密集研究计划。该研究计划发现，尾矿中微生物产生的甲烷持续起泡，称为沸腾。除了对温室气体排放的影响外，这种甲烷沸腾还是一种潜在的机制，可以将残留的石油碳氢化合物(PH)和环烷酸(NA)输送到水柱中。这些化合物的运输有可能对生物地球化学循环和生物圈内生态系统的发展产生负面影响。这项研究计划将专注于表征能够在BML内持续产生微生物甲烷的化合物，并将评估在甲烷沸腾过程中PH和/或NA被输送到水柱的潜力。这项研究不仅将为AOSR中BML和未来的PL的适应性管理提供信息，从而有助于AOSR尾矿管理和回收的关键优先事项，而且它还将为控制富有机环境中石油烃运输和命运的过程提供基本见解，这些过程可以转移到其他受影响的环境，包括港口、工业海岸线和溢油地点。它还将培训一支由高技能人员组成的多样化团队，这些人员能够为石油工业、环境修复、政府监测和学术研究做出贡献，了解富含有机物质和受石油影响的环境中的生物地球化学循环。

Petroleum in the Alberta Oil Sands Region (AOSR) is a key component of the Canadian economy. Currently reclamation of land impacted, and tailings produced, by surface mining operations in the AOSR is a central industry and environmental priority in Canada. Syncrude Canada Ltd. has commissioned the first example of oil sands reclamation by water capped tailing technology (WCTT) via the development of an 8 km2 pit lake (PL) Base Mine Lake (BML) in 2012. While PL reclamation is commonly employed for tailings management in hard rock mining, the AOSR is unique due to the organic rich nature of the tailings. Since 2012 Syncrude has supported an intensive research program aimed at understanding the development of BML This research program has identified ongoing bubbling, known as ebullition, of microbially produced methane from the tailings. In addition to its implications to greenhouse gas emissions, this methane ebullition represents a potential mechanism for the transport of residual petroleum hydrocarbons (PH) and naphthenic acids (NA) into the water column. Transport of these compounds has the potential to negatively impact biogeochemical cycling and ecosystem development within BML. This research program will focus on characterizing compounds that can drive ongoing microbial methane production within BML and will evaluate the potential for PH and/or NA to be transported to the water column during methane ebullition. This research will not only inform adaptive management of BML and future PL in the AOSR thereby contributing to the key priorities of tailings management and reclamation of the AOSR, but it will also provide fundamental insights into the processes controlling petroleum hydrocarbon transport and fate in organic rich environments that can be transferred to other impacted environments including harbours, industrial shorelines, and spill sites. It will also train a diverse team of highly skilled personnel capable of contributing to the petroleum industry, environmental remediation, government monitoring and academic research in understanding biogeochemical cycling in organic rich and petroleum impacted environments.