Hydro-mechanical Simulations of Well Abandonment at the Ketzin Pilot Site for CO2 Storage Verify Wellbore System Integrity

In geological underground utilization, operating and abandoned wells have been identified as main potential leakage pathways for reservoir fluids. In the scope of the well abandonment procedure currently carried out at the Ketzin pilot site for CO2 storage in Germany, we implemented a hydro-mechanical wellbore model to assess the integrity of the entire wellbore system. Thereto, we investigated the impacts of stress changes associated with site operation and abandonment, including the final casing removal and cement backfill to be undertaken for well abandonment. Simulation results show a high unlikeliness of potential formation of fluid leakage pathways in the wellbore system.