Seven Mile Hill Wind Energy Project

Project Description

PacifiCorp (doing business as Pacific Power/Rocky Mountain Power) (Applicant) is the developer and operator of the existing Seven Mile Hill I and II (also known as Seven Mile Hill) Wind Energy Project (Project) located in Carbon County, Wyoming. The Project consists of 79 wind turbines and associated infrastructure (roads, transmission lines, etc.) and has been operating since January 17, 2009. The expected life of the project is at least 30 years. The Applicant submitted an Incidental Eagle Take Permit (IETP) (revised and final) application and ECP to the U.S. Fish and Wildlife Service (Service) on December 30, 2019, requesting the maximum 30-year permit.

Potential Eagle Impacts

Monitoring conducted at the Project since 2009 has documented bald and golden eagle mortalities. Take, including killing of eagles, is prohibited by the 2016 Bald and Golden Eagle Protection Act (Eagle Act). However, the Service has been delegated the authority to issue eagle take permits, where the take is determined to be compatible with the preservation of eagles. The Service will issue permits for such take only after an applicant has committed to undertake all practical measures to avoid and minimize such take and mitigate anticipated take to the maximum extent achievable.

The Applicant has developed and provided an ECP that summarizes project design, construction and operational measures taken to avoid and minimize impacts to eagles, and results of pre- and post-construction monitoring efforts.

The Service has completed an Environmental Assessment (EA) for the potential issuance of the permit decision under the 2016 Eagle Act regulations. The EA assesses the potential effects of issuing an IETP and a No Action alternative (i.e., do not issue a permit) on the human and natural environment. The Service’s Collision Risk Model (CRM) predicts that up to 3.78 bald eagles and up to 7.74 golden eagles could be killed incidentally on an annual basis as a result of the operation of the Project. This was partially derived using the Evidence of Absence statistical approach to inform the CRM by analyzing post-construction mortality monitoring data collected at the Project site from 2016 –2019. Additionally, national priors were used to update the CRM eagle exposure parameter. Lastly, collision probability prior was updated iteratively using the expected value of fatalities and adjusted for applicant-provided operational daylight hour data collected during monitored years (2016-2020).

Project Review

The Service has an independent statutory responsibility under the National Environmental Policy Act (NEPA) to evaluate its own actions related to the Project, namely the possible issuance of an IETP. A draft EA evaluating the impact of issuing (and not issuing) an IETP for the existing Project was made available for a 30-day comment period. We received one letter containing comments and recommendations during the public review period. It has been determined that there is no new significant information, and the Service has prepared a Finding of No Significant Impact (FONSI) in accordance with NEPA regulations (40 C.F.R § 1508.13). The IETP will be issued under the 2016 Eagle Act regulations and will authorize non-purposeful take of bald eagle and golden eagles.

News and Updates

The U.S. Fish and Wildlife Service (Service) has released the final Environmental Assessment (EA), Finding of No Significant Impact (FONSI), and findings document for the issuance of an Incidental Eagle Take Permit (IETP) for the operation of the Seven Mile Hill I and II (also known as Seven Mile Hill) Wind Energy Project (Project) facility located in Carbon County, Wyoming. The 30-year permit authorizes the potential take of bald and golden eagles associated with the operation of the existing 79-turbine wind energy Project, and outlines required conservation and compensatory mitigation measures for minimizing and offsetting potential eagle take, pursuant to the 2016 regulations of the Bald and Golden Eagle Protection Act (Eagle Act). PacifiCorp (doing business as Pacific Power/Rocky Mountain Power) (Applicant), is the developer and operator of the existing and operational Project.

Request Documents

If you would like a copy of the documents associated with this project, contact Tomas Kamienski or Rob Doster. 

Documents available upon request: 

• Finding of No Significant Impact (FONSI)
• Final Environmental Assessment
• Eagle Conservation Plan (ECP)