Safety criteria for CO2 geological storage: Determination workflow and application in the context of the Paris Basin

Abstract : For carbon dioxide capture and storage to make an effective contribution in reducing greenhouse gas emissions, a large number of storage sites will be required. Safety will have to be demonstrated for each of these sites. We present in this paper a simple and flexible framework to assess safety of a CO 2 storage site in a time-efficient manner. It includes the identification by an expert panel of the relevant risk scenarios. Their evaluation privileges analytical or semi-analytical modelling with conservative assumptions. Uncertainty is managed in order to thoroughly represent and propagate the nature of information relative to the site properties. We illustrate the application of this framework with a case study in the context of the Paris Basin. The workflow described is not a complete risk assessment framework, but it constitutes a useful tool for an operator at an early stage of a project or to iteratively screen safety issues, or for a regulating authority to review the safety conditions of a project.