Constraining offshore methane leakage from plugged and abandoned petroleum wells using marine microbial genomics

根据对北海和墨西哥湾的研究得出的估计，加拿大东海岸的620口威尔斯井每年可能排放多达200万吨甲烷，总体积相当于1.6亿吨二氧化碳。到目前为止，还没有研究来确定甲烷泄漏超过背景水平的程度，有多少进入大气，甲烷营养的作用（甲烷食用）微生物在减缓其释放方面的作用，以及基于基因组学的新生物技术在加速和加强补救方面的潜力。甲烷排放的气候变暖潜力是二氧化碳的84倍，是一个重大的环境问题。在2021年COP 26峰会上，加拿大政府与100多个国家签署了《全球甲烷承诺》，承诺加拿大将超过目前的监管要求（目标是到2025年减少40-45%），并制定新的监管措施，到2030年将石油和天然气甲烷排放量从2012年的水平减少至少75%。到目前为止，监管机构并不要求评估潜在的海底甲烷泄漏，因为假设这些泄漏得到缓解-但事实并非如此。至关重要的是，通过严谨的科学来更好地理解这一监管鸿沟，这将为省级和国家的政策和政府战略提供信息，以实现净零排放。卡尔加里大学和圣玛丽大学的微生物学家和地球化学家将与其他大学、私营部门（Stantec，Pro Oceanus，Kraken Robotics，自治领潜水），和政府组织（新斯科舍省自然资源和可再生能源部）为了填补这一知识空白，对新斯科舍省近海的废弃井场进行全面调查，收集海底沉积物，在最近废弃的和遗留的井场附近采集水柱和大气样本，以解决这些问题。该项目的成果将为减少温室气体排放的政策制定和规章制度提供依据，并为减少废弃和未来近海威尔斯油井的甲烷排放提供工具。

Based on estimates derived from studies in the North Sea and Gulf of Mexico, Canada's 620 east coast wells could be emitting as much as 2 million tonnes of methane per year, a total volume equivalent to 160 million tonnes of carbon dioxide. To date there has been no research to identify the extent to which methane leakage above background levels is occurring, how much enters the atmosphere, the role methanotrophic (methane eating) microorganisms play in mitigating its release, and the potential for new genomics-based biotechnologies to accelerate and enhance remediation.Over a 20-year time scale, methane emissions have a climate warming potential as much as 84 times that of carbon dioxide and represent a significant environmental concern. The Government of Canada joined more than 100 countries as a signatory to the Global Methane Pledge at the COP26 summit in 2021 committing Canada to exceed current regulatory requirements (aimed at a 40-45% reduction by 2025) and to develop new regulatory measures to reduce oil and gas methane emissions by at least 75% below 2012 levels by 2030. To date, regulatory authorities do not require assessment of potential subsea methane leakage as it is assumed that these leaks are mitigated - but they are not. It is critical that this regulatory chasm is better understood with rigorous science that will inform policy and government strategy, both provincially and nationally, for net zero emissions.Microbiologists and geochemists from the University of Calgary and Saint Mary's University will partner with other universities, the private sector (Stantec, Pro Oceanus, Kraken Robotics, Dominion Diving), and government organizations (Nova Scotia Dept of Natural Resources & Renewables) to fill this knowledge gap through a comprehensive survey of abandoned well sites in the offshore of Nova Scotia to collect seabed sediment, water column and atmospheric samples in proximity to recently abandoned and legacy well sites to address these questions. The results of the project will provide the basis for policy development and regulations for greenhouse gas emissions reduction, as well as tools to mitigate methane emissions from both abandoned and future offshore petroleum wells.