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Underground Injection Control (UIC)

Wyoming Underground Injection Control Program: Class VI Primacy

The EPA is approving an application from the State of Wyoming under the Safe Drinking Water Act (SDWA) to implement the UIC program for Class VI injection wells to protect underground sources of drinking water located within the state, except within Indian lands. EPA will continue to administer all well classes within Indian lands. Class VI wells are used for the underground injection of carbon dioxide into deep subsurface rock formations for long-term storage.

The EPA's approval is based on a legal and technical review of the State of Wyoming’s application as directed in the Code of Federal Regulations (CFR) at 40 CFR part 145. As a result of this review, EPA is approving Wyoming’s application because it meets or exceeds all applicable requirements for approval under the SDWA section 1422 and the Agency has determined that the state is capable of administering a Class VI UIC program in a manner consistent with the terms and purposes of the SDWA and all applicable regulations to protect underground sources of drinking water.

The Final Rule for the Wyoming Class VI primacy action becomes effective upon publication in the Federal Register.

The document attached below is an unsigned copy of the final FR Notice.  Once the Office of the Federal Register has received the final document with the Administrator’s signature, this page will be updated and the direct link will be provided. Anyone experiencing any accessibility issues while trying to access the document attached here should contact Molly McEvoy ( at (202)-564-4765.

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