On August 1, EPA’s comment period on its proposal to grant Texas “primacy” over permitting and enforcement of Class VI underground injection wells closed, marking another milestone in the expansion of state-managed Carbon Capture and Sequestration (CCS) regulation. Class VI wells are used for CCS, or the geologic sequestration of atmospheric and other streams of carbon dioxide. With that, while EPA still needs to review comments, Arizona and Texas are expected to be granted primacy – the authority to manage Class VI regulation instead of EPA.
If approved, Arizona and Texas will join the small group of states with authority to regulate their own CCS wells. This regulatory authority would open both states to Class VI business – allowing them to streamline permitting for CCS projects, reduce delays and increase predictability for developers and investors of both carbon capture and collection technologies broadly, and injection technologies specifically. As early entrants to the state CCS regulation field, a small group of states will serve as national models and leaders as CCS activity grows nationally and internationally.
Background regarding Class VI Wells and the National Landscape
Class VI wells are regulated by the Underground Injection Control (UIC) program of the Safe Drinking Water Act. In order to grant primacy, EPA must determine under Section 1422 of the Safe Drinking Water Act that a state meets its minimum requirements for the UIC program, and the state must demonstrate to EPA that it has jurisdiction over and the necessary administrative process, including civil and criminal enforcement penalties, needed to administer, a given well class. Only four states to date have Class VI primacy – Louisiana, North Dakota, Wyoming, and, most recently in February 2025, West Virginia. Several others states – Alabama, Alaska, Colorado, Oklahoma, Mississippi, Nevada, New Mexico, and Utah – are all in the “pre-application” phase of obtaining either primacy or a program revision with regards to class VI wells. Only Texas and Arizona are in the Proposed Rule phase. The comment period on EPA’s proposal for Arizona closed July 3, 2025. After a Public Hearing on July 24, the comment period on EPA’s proposal for Texas closed on August 1.
EPA’s Proposed Rule for Arizona and Texas
EPA proposed primacy for Arizona on May 19, 2025, and for Texas on June 17, 2025. These proposed rules outline the Agency’s intent to approve Arizona’s and Texas’s applications for Class VI primacy. Each state submitted an application that showed a nearly ready-to-go regulatory system in place. Arizona’s application, submitted February 16, 2024, proposed primacy to regulate Class I-VI wells, showing adopted regulations based on state notice and public hearing, and proposing to regulate the wells through the Arizona Department of Environmental Quality (ADEQ). Texas’ application, submitted February 20, 2025, also speaks to both its capacity and methodology for managing Class VI wells if granted the authority. Regulation would run through the Texas Railroad Commission (RRC), where the RRC currently regulates Class II wells in Texas. EPA concluded that Arizona and Texas each met the UIC permit requirements and that they had incorporated the necessary procedures to support a Class VI compliance evaluation and civil and criminal enforcement program. As these proposals undergo final consideration, primacy is expected in the coming months. EPA’s proposed rule in Texas enjoys bipartisan support, with representatives with multiple Democratic and Republican representatives joining the Administration’s national and Region 6 leadership to support the proposal, as not only “a promising step in Texas’s effort to reduce carbon dioxide levels in our atmosphere” but also a testament to Texas’s leadership in “energy production,” of which “pioneering carbon capture and storage practices” forms an important part.
Conclusion
Arizona and Texas are set to become members of a small class of states that are defining state-managed CCS regulation across the nation. With eight other states already working towards this goal, CCS-watchers can expect to see CCS opportunities grow over the next years as Arizona and Texas continue to build momentum around CCS development.
