Demonstrating the integrity of plugged and abandoned legacy wells during CO2 storage projects is a crucial requirement for regulators, stakeholders, and operators. The corrosive nature of CO2 may affect the integrity of such wells, jeopardizing the long-term containment of the CO2. This study illustrates the new capabilities, tailored for CO2 storage applications, of a modeling framework that provides a quantitative, risk-based assessment of the long-term integrity of legacy plugged and abandoned wells. Three new modeling modules are added to this integrated framework to account for key concerns.
Introduction
The plugging and abandonment (P&A) framework translates all well-flow paths into a numerical, spatially discretized, grid-based, digital representation. Multiple grid cell types represent the various well components (e.g., intact and impaired cement, casing, tubing, reservoir formation, and fluid-filled annular space). Appropriate fluid-flow properties are allocated to each cell.
