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CWA Section 401 Certification

Final Rule Implementation Materials

Pursuant to the April 10, 2019 Executive Order on Promoting Energy Infrastructure and Economic Growth, the U.S. Environmental Protection Agency (EPA) engaged with states, authorized tribes, and relevant federal agencies to identify provisions that require clarification within Section 401 of the Clean Water Act (CWA) and related federal regulations and guidance. On June 1, 2020, the EPA finalized the "Clean Water Act Section 401 Certification Rule" to implement the water quality certification process consistent with the text and structure of the CWA. The final rule became effective on September 11, 2020. EPA created the following internal materials to support EPA’s implementation of the final Clean Water Act Section 401 Certification Rule.

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