Baseline geochemical characterization of potential receiving reservoirs for carbon dioxide in the Greater Green River Basin, Wyoming

Geologic sequestration of anthropogenic carbon dioxide (CO 2 ) will be a necessary part of a carbon management strategy for reducing atmospheric CO 2 emissions so long as fossil fuels are a significant part of the energy mix. Proposed federal and state regulations for underground injection of CO 2 require that underground sources of drinking water be protected. Accordingly, proposed federal regulations require analysis of the suitability of different receiving formations for geologic sequestration. This study compiles all available water quality data for four potential CO 2 receiving formations in the Greater Green River Basin of southwestern Wyoming. The Greater Green River Basin encompasses two large geologic structures, the Moxa Arch and Rock Springs Uplift, which potentially are capable of storing commercial quantities of CO 2 in a number of formations, including the Nugget Sandstone, Tensleep/Weber Sandstone, Madison li mestone, and Bighorn Dolomite. The data suggest that except along the basin margins, the Tensleep/Weber, Madison, and Bighorn Formations are suitable targets under proposed federal and state geologic sequestration regulations. However, low total dissolved solids in Nugget Sandstone groundwater in parts of the Rock Springs Uplift suggest the potential for local, fracture-assisted recharge in this area. For this reason the Nugget Sandstone is less suitable than the deeper formations for CO 2 storage in the Rock Springs Uplift.