In recent years, carbon capture and storage (CCS) has been advocated as a means to continue using fossil fuels until carbon-free energy systems are developed while at the same time reducing anthropogenic carbon emissions (IPCC, 2005). CCS entails capturing carbon dioxide (CO2) from fossil fuel combustion and sequestering it from the atmosphere for thousands to hundreds of thousands of years. Storage can be accomplished through mineral carbonation, ocean storage, biological storage, or geologic storage. For a variety of reasons, geologic carbon sequestration (GCS) is the technology that can be deployed in the shortest timeframe while capturing significant amounts of CO2.
Given the wide range of stakeholders this publication is intended for and its broad subject matter, it is unlikely that any one reader will be well versed in all topics. Thus, this report has introductory material incorporated into each content area to guide the reader through these possibly unfamiliar subjects. For example, in discussing the chemistry of CO2, phase diagrams are explained, so the discussion of the phase relations of injected CO2 and its implications for project design, safety, and monitoring can be understood by the non-specialist. Likewise, the regulatory section provides an overview of environmental laws before investigating the details of the Safe Drinking Water Act’s UIC program. Equipped with this background information readers can effectively assess the various claims and counterclaims about CCS.