The National Energy Technology Laboratory and Sandia National Laboratories are developing a geochemical and desalination assessment tool to examine changes in water quality in brackish water formations, CO2 plume migration during injection, and water extraction and treatment options for new uses. The initial assessment focused on the San Juan Basin of northwestern New Mexico. An extended analysis examines other regions of the country such as the southeastern US. The regional assessment framework modeled changes in San Juan Basin groundwater chemistry using REACT software and also modeled flux and trapping of supercritical CO2 in saline formations using TOUGH2. Initial water-CO2-formation reactions include dissolution of carbonate minerals as expected and suggest that very little CO2 will be sequestered in mineral form within the first few centuries. CO2 plumes within target formations migrate from a given injection well at rates commensurate with the specified well spacing, design, and other constraints. Water treatment options vary depending upon site-specific water characteristics. The high-efficiency reverse osmosis system shows promise for economical desalination at the volumes of recovered water under consideration. The extended analysis examines feasibility for combined water extraction, treatment, and beneficial use with CO2 storage in the southeastern US. This includes examining salinity levels of regional saline formations, evaluating water usage for select power plant profiles, and determining cost and systems management requirements in an effort to develop a decision support analysis for potential CO2 storage and extracted water use at the power plant level.