EPA Proposes to Give Colorado Primacy to Protect Underground Water Resources

DENVER - Today, U.S. Environmental Protection Agency (EPA) announced its proposed approval of the state of Colorado's request to administer permitting for Class VI underground injection wells (UIC) under the Safe Drinking Water Act (SDWA). The proposal would support EPA's Powering the Great American ComebackExit EPA's websiteinitiative,which prioritizes clean and safe water for Americans, restoring American energy dominance and advancing cooperative federalism. EPA is accepting public comments on the proposal through May 4, 2026.

"Congress laid out a clear vision under the Safe Drinking Water Act for delegating decision-making from EPA to the states," said EPA Regional Administrator Cyrus Western. "This primacy proposal supports Congress' vision and recognizes that Colorado has the local expertise to protect its groundwater resources while supporting economic growth."

After conducting a comprehensive technical and legal review, EPA is seeking comment on whether Colorado's proposed UIC program meets all requirements for approval and that the state will implement and enforce the program consistent with the SDWA.

EPA is committed to expediting the review of UIC permits and primacy applications received by the agency. Today's proposed approval helps fulfill this commitment. To date, six states have received primacy for Class VI wells, including North Dakota and Wyoming in EPA Region 8. More information about UIC primacyExit EPA's websiteis available on the EPA website.

EPA is requesting public comment on the agency's proposed decision for 45 days after the proposal is published in the Federal Register. The public can comment on the proposal online through the Federal RegisterExit EPA's website using Docket ID No. EPA-HQ-OW-2025-2829.

EPA will hold a public hearing virtually on April 23, 2026, from 5-8 p.m. Mountain Standard Time. Registration for the hearing is available onlineExit EPA's website or by email at [email protected].

Background

UIC programs under SDWA play a key role in our nation's economic future by protecting underground drinking water supplies and ensuring that byproducts of industrial and energy projects are safely stored underground. Class VI wells are used to inject carbon dioxide into deep rock formations for long-term underground storage, also known as geologic sequestration.