Final rule · 2026-20846

Colorado Underground Injection Control (UIC) Program; Class VI Primacy

The U.S. Environmental Protection Agency (EPA or the Agency) is approving an application from the State of Colorado that requests primary enforcement responsibility (primacy) for Class VI injection wells under Safe Drinking Water Act (SDWA) section 1422. The EPA's approval of the State's UIC program primacy application will allow the Colorado Energy and Carbon Management Commission (ECMC) to issue and enforce UIC Class VI permits for geologic carbon sequestration. The EPA will remain the permitting authority for Class VI injection wells on Indian lands within the State. With this action, the EPA also intends to codify previously approved, non-substantial changes to Colorado's UIC program for Class II injection wells.