EFSEC received an application for site certification (ASC) for the Horse Heaven Wind project on February 8, 2021. EFSEC held an informational public meeting and land use hearing on March 30, 2021. EFSEC issued a determination of significance on April 5, 2021, and a SEPA scoping notice on May 11, 2021. On May 17, 2022, EFSEC issued an order finding the project consistent with land use regulations. In August 2023, EFSEC conducted adjudicative hearings for the project. EFSEC issued a final environmental impact statement (EIS) for the project on October 31, 2023.
EFSEC submitted their recommendation to Governor Inslee on April 29, 2024. He sent the project back to EFSEC for reconsideration on May 25, 2024. EFSEC subsequently sent a revised recommendation to the Governor on September 17, 2024. He approved the project and signed the site certification agreement (SCA) on October 18, 2024. The project is currently under litigation.