Plug & abandon strategies for Canada's oil & gas wells

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With the increasing public scrutiny of the oil and gas industry in the past 10-20 years, the attention of the**industry, regulatory authorities and all levels of government is driven towards tackling serious questions of**environmental stewardship that afflict the industry. High amongst the list is the question of safe long-term**abandonment of oil and gas wells. By 2013, more than 550,000 oil & gas well had been drilled in Canada, most**of which were in the Western Canada Sedimentary Basin. In Alberta alone, 35% of total wells are abandoned:**this number adds up to around 151,000 abandoned wellbores in the province. Much of the current well stock is**30-40 years old or more. Canada is entering an era of P&A (Plug and Abandonment) in which 1000's of wells**will be abandoned annually for the foreseeable future. Environmental & public safety concerns abound.****Long term sealing of wellbores requires proper placement of sealing materials (cement), avoidance of**contamination/mixing and ensuring a good bond of the cement to the surrounding rock. This 4-year project is**about the engineering design of P&A operations. The project has 2 key objectives. First we will assess the**status of typical Canadian P&A operations, well architectures and regulatory practices, within a more global**context. We will conduct a detailed review of the scientific and engineering literature as it pertains to**longevity/sealing, clarify knowledge gaps and expose technological issues. Second, through a network of**collaborative Canadian researchers and targeted complementary sub-projects we will provide physical and**engineering rationale for regulatory and operational decisions that concern fluid mechanical issues (placement,**cleaning, mixing, and thus potential bonding). Our team will conduct 7 complementary and interlinked studies**addressing P&A knowledge gaps while providing fundamental advances, using a combination of experimental,**analytical and computational methodologies, combined with field survey work with industrial partners.