EPA has approved Colorado’s request for Class VI primacy, giving the state’s Energy and Carbon Management Commission (ECMC) authority to permit and enforce the wells used to store carbon dioxide underground. The final rule ran in the Federal Register on Oct. 13 and takes effect Nov. 12.
From that date, any new Class VI application goes to ECMC instead of EPA Region 8 in Denver. EPA keeps the Class VI wells on Indian lands in Colorado and stays on as overseer, with quarterly noncompliance reports and annual performance reports due from the state.
What Class VI primacy changes for Colorado carbon storage projects
Not much is moving yet. According to ECMC, one Colorado operator already holds an EPA-issued Class VI permit and a second has an early-stage application pending. Both transfer to the state. Neither operator is named.
The rules developers will work under are already on the books. ECMC finalized them in December 2024 after ten rulemaking and primacy hearings. Every project needs a pre-application meeting, a 2,000-foot minimum setback from homes and businesses, and injection generally deeper than about 2,600 feet. Construction can start under a Commission-approved development plan, but injection needs a separate Authorization to Inject, which ECMC grants only after it reviews construction and testing data. Each project also gets a public comment period.
Long-term liability has a home, too. Operator fees fund a Geologic Storage Stewardship Enterprise, created under HB25-1165, that can take over a site after closure. ECMC hasn’t published the fee amounts or any financial assurance figures.
Why state carbon storage permitting matters to drillers and pipeline contractors
The argument for primacy is speed. EPA’s rule cites a “national backlog” of Class VI applications, and Gov. Jared Polis said state oversight “will allow fast decisions” on permits. That’s a claim, not a commitment. ECMC hasn’t published a review clock, and an agency that has run Class II oil and gas injection wells since 1984 still has to staff up for a heavier technical review: plume modeling, area-of-review work and long-term monitoring plans.
Law firm Hunton Andrews Kurth counts Colorado as the seventh state with Class VI primacy. North Dakota and Wyoming got there years ago, and Texas won approval last November. The practical effect for a developer is a nearer regulator, one that already knows the local geology and the operators’ Class II files.
The construction scope is familiar. A storage site needs injection and monitoring wells drilled and completed to Class VI standards, CO2 gathering lines, compression and metering. Those are the same rigs and crews already working Colorado’s oil and gas basins. What’s been missing is a permit queue anyone could plan a drilling schedule around.
Other states are making the same bet on different rulebooks. Georgia is chasing a handoff of highway environmental reviews through NEPA assignment, on the theory that a state agency moves faster than a federal one applying the same rules.
Comments on the Colorado rule and the open questions
EPA received 11 written comments. Most supported approval, including the Ground Water Protection Council and Reliant Carbon Capture and Storage. Opponents raised Tribal consultation and groundwater risk from CO2 plume migration. The Southern Ute Indian Tribe backed the rule but asked EPA to define “Indian lands,” which the final rule doesn’t do.
That gap matters in southwest Colorado, where the jurisdiction line decides which agency a developer files with. It’s the kind of question that’s cheap to settle before a project is sited and expensive after.
The first new application filed with ECMC after Nov. 12 is the real test. How long it takes to clear will tell developers more about Colorado than the primacy rule does.