Risk Assessment and Monitoring Techniques for Geological CO2 sequestration

Abstract:

The National Risk Assessment Partnership (NRAP) has developed an integrated assessment model (NRAP-IAM-CS) of a carbon storage system that is able to model the full subsurface system from the reservoir to groundwater aquifers and release into the atmosphere. The approach taken uses reduced order models so that systems simulations occur rapidly, even for simulations times of hundreds to thousands of years. In that way, uncertainties of the entire system can be probed in a reasonable time period, using a Monte Carlo approach. The model presented here uses third generation NRAP ROMs that are able to realistically represent several key properties of reservoirs, wells, seals, and groundwater aquifers. Results from the NRAP-IAM-CS model are used to quantify risk profiles for selected parameter distributions of reservoir properties, seal properties, numbers of wells, well properties, thief zones, and groundwater aquifer properties. A series of risk profiles show how the risk under different storage conditions evolves over time, both during injection, in the near-term post injection period, and over the long term. In this study, the NRAP-IAM-CS was also used to investigate the importance of different parameters across the system on risk of leakage and risk of groundwater contamination, under different storage conditions.