Due to public health concerns related to the spread of the novel corona virus (COVID-19), the Energy Facility Site Evaluation Council office (EFSEC) is closed to the public as of March 16, 2020. All EFSEC staff are telecommuting until further notice and EFSEC operations will continue remotely. You may reach EFSEC by phone (360) 664-1345 or by email efsec@efsec.wa.gov during regular business hours, 8 am – 5 pm, Monday through Friday. EFSEC Council meetings will be held by teleconference until further notice. Please check this site regularly for updates.

Changes are coming to EFSEC

Effective June 30, 2022 EFSEC has become an independent state agency through the passage of E2SHB 1812 by the 2022 Washington State Legislature. There will be several changes to internal structure and operations, most notably EFSEC no longer depends on the Utilities and Transportation Commission (UTC) for administrative and staff support services. Click here to learn more information.

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Horse Heaven SEPA


The State Environmental Policy Act (SEPA) is a Washington State law known as the Revised Code of Washington (RCW) 43.21C.  RCW 43.21C was enacted in 1971 which requires state and local agencies to identify and analyze the adverse environmental impacts of a proposal before making a decision on that proposal (RCW 43.21C.030). As part of analyzing the proposal for impacts, EFSEC sends data requests to the applicant requesting additional information or clarification regarding their proposal and/or the site. When a decision is made to prepare an Environmental Impact Statement (EIS) for SEPA review, the EIS process is initiated with a Determination of Significance (DS). EFSEC announces the DS in a Scoping Notice which begins a public comment period. EFSEC is required to consider all comments received during Scoping in determining the Scope of the EIS but is not required to respond to those comments in writing. A Scoping Report or Memo can be prepared and informs the public about the comments received during Scoping and how that information will set the Scope of the EIS. Once the Scope of the EIS is determined, a draft EIS is prepared.

For more information on the SEPA process visit the Certification Process page.

Data Requests

Data Request 4

Document Title Document Date
Data Request 4 Data Layers 11/02/2021
Data Request 4 Table 10/27/2021

Data Request 5

Data Request 6

Document Title Document Date
Data Request 6 Table 01/13/2022


SEPA Scoping

Determination of Significance

SEPA Comments Received

The SEPA Scoping comment period closed as of June 10, 2021.

Comments outside of a comment period can be sent to the EFSEC general mailbox at any time: EFSEC@utc.wa.gov

Important Note: Public comments submitted to the Council via the internet or in writing become public records under the Washington State Public Records Act (RCW 42.17). Information included in the comment such as the commenter's e-mail and mailing address becomes a public record once it is provided to EFSEC and may be subject to public inspection and copying if not protected by federal or state law. For additional information please see our Privacy Notice.