On October 13, 2026, the U.S. Environmental Protection Agency (“EPA”) approved Colorado’s application to take over primary permitting and enforcement authority, known as “primacy,” for Class VI underground injection control (“UIC”) wells—wells used for the geologic sequestration of carbon dioxide—under section 1422 of the Safe Drinking Water Act (“SDWA”).1
This approval culminates a multi-year process that began in 2023 when Colorado’s legislature expanded the Energy and Carbon Management Commission’s (“ECMC”) authority to seek primacy over geologic sequestration. Following stakeholder engagement and rulemaking in 2024, ECMC submitted its primacy application to EPA in October of 2025. EPA proposed to approve the application in March 2026, held a public hearing in April 2026, and received public comments before finalizing the approval.
EPA’s approval means that beginning on November 12, 2026, ECMC will now issue and enforce Class VI UIC permits in Colorado instead of EPA.2 EPA will still handle Class VI permitting on tribal lands in the State.3 EPA is also using this rule to formally adopt minor changes to Colorado’s Class II UIC program (applicable to wells used to inject fluids associated with oil and natural gas production).4
Key Takeaways
- Colorado is joining the list of States that have primacy over Class VI UIC permitting and enforcement.
- For project developers in Colorado, primacy may allow permitting to move more quickly.
- Colorado’s requirements go beyond EPA’s requirements in several respects:
- Every proposed Class VI project must include a cumulative impacts analysis, and proposals with negative net cumulative impacts on any disproportionately impacted community must be denied; and
- Class VI UIC wells are required to have 2,000-foot setbacks from residences, schools, high occupancy buildings, commercial building units, and childcare centers.
As ECMC begins accepting Class VI applications next month, project developers should be aware that the agency will process applications primarily on a first-submitted basis, with consideration given to application completeness and project scope. Understanding ECMC’s application requirements and Colorado’s administrative procedures will be essential for project developers seeking timely permitting under the new program.
1 Colorado Underground Injection Control (UIC) Program; Class VI Primacy, 91 Fed. Reg. 64,780 (Oct. 13, 2026).
2 Id. at 64,781.
3 Id.
4 Id.
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