South Plains Complex

The South Plains Complex carbon storage project is a large-scale CO₂ enhanced oil recovery (EOR) and geologic sequestration operation developed and operated by Occidental (Oxy) in the Permian Basin, Texas, encompassing approximately 38 operating units across the Slaughter and Levelland Fields. CO₂ injection began in the mid-1980s and is conducted under Class II permits regulated by the Texas Railroad Commission, with monitoring and accounting under EPA Subpart RR to quantify long-term geologic storage. The South Plains Complex injects CO2 obtained from the Bravo CO2 Pipeline Network and from the Mallet CO2 gas processing plant (Mallet Plant) and the project sends its produced fluids to Mallet Plant for separation and redistribution. Several other nearby EOR operations also utilize the Bravo CO2 Pipeline and the Mallet Plant. The project injects CO₂ into the Lower San Andres Formation, a dolomitized carbonate reservoir with multiple regional confining layers composed of anhydrite and evaporite sequences that provide long-term containment. CO₂ is sourced from pipeline networks and recycled from produced fluids, using water-alternating-gas injection to maintain reservoir pressure while mobilizing hydrocarbons and simultaneously storing CO₂. Historical operations indicate approximately 77 million tonnes of CO₂ have been geologically stored through 2023, with modeling forecasting cumulative storage reaching roughly 94 million tonnes through continued operations extending toward 2080.