Development of Science-Based Permitting Guidance for Geological Sequestration of CO2 in Deep Saline Aquifers Based on Modeling and Risk Assessment

Jean-Philippe Nicot, principal investigator

The project is funded by the Department of Energy in collaboration with Pacific Northwest National Lab. Geological sequestration of CO2 has been recognized as an important way of mitigating increase in atmospheric CO2. The objective of this study is to develop science-based permitting procedures for CO2 sequestration that are based on

  • review of existing permitting procedures (e.g., deep-well injection and high-level radioactive waste disposal),
  • simulation of flow and transport of CO2 in a generic reservoir and evaluation of CO2 migration pathways (diffuse vs. focused) and potential leakage,
  • evaluation of risk on the basis of probability distributions of input parameters (e.g., permeability, densities of faults,) and related consequences, and
  • ranking of parameters analyzed in the risk assessment to allow site characterization and monitoring to focus on critical parameters for CO2 sequestration.

Permitting is a critical issue for stakeholders because highly restrictive permitting guidelines could limit the use of geologic sequestration of CO2, whereas lax regulation could result in public objection and negative consequences for injection. Our studies will focus on long-term (hundreds to thousands of years) migration of CO2 in the subsurface in the Texas Gulf Coast and Ohio–West Virginia areas, where large volumes of CO2 are currently released and high-quality data are available from pilot injections. The applicability of results from these regions to other sites will be evaluated on the basis of a comparison with the national database on saline aquifers. This comprehensive approach to development of robust, reliable permitting procedures that is based on a thorough evaluation of existing data and risk assessment will increase confidence in operators, regulators, the public, and other stakeholders in the geologic sequestration process.

For more information, please contact Jean-Philippe Nicot, principal investigator.
Telephone 512-471-6246;
e-mail jp.nicot@beg.utexas.edu.

August 2005