Opponents of the proposed Horse Heaven wind and solar project in southeast Washington have asked a state siting council to postpone hearings until the council releases an environmental report on the project.

Benton County, the Yakama Nation and Tri-Cities C.A.R.E.S. stated in separate requests May 18 that without a final environmental impact statement they won’t know exactly what they are testifying about.

“This can’t be the way the system works,” C.A.R.E.S. attorney J. Richard Aramburu said. “We want to be able to use the document in our testimony.”

Scout Clean Energy of Boulder, Colo., has proposed a wind and solar installation that would stretch for 25 miles and encompass 113 square miles near the Tri-Cities. The turbines also would be visible in Franklin and Walla Walla counties, as well as Oregon.

The Energy Facility Site Evaluation Council is reviewing the project and will recommend to Gov. Jay Inslee whether it be approved or denied. Most council members are in the Inslee administration.

The council’s review will include formal hearings before an administrative law judge on how the turbines and solar panels will affect wildlife and the landscape and what Scout should do to minimize the impacts.

The county, tribe and C.A.R.E.S., a citizens group, have intervened to participate in the formal proceedings as witnesses. Judge Adam Torem has set 10 hearing dates beginning Aug. 10.

Hearing topics will include subjects typically covered in an environmental impact statement, such as how the project will affect hawks, habitat, tribal cultural resources and society, including agriculture.

EFSEC released a preliminary environmental impact statement in December, but has not indicated when it will have a final report. EFSEC requested more information from Scout for the final report.

The final report may address opponents’ concerns, or may not, and may raise new concerns, Aramburu said. “People should have an opportunity to look at the evidence,” he said.

“We didn’t create this problem,” he said. “There’s nothing we can do to push this along.”

EFSEC needed one to two business days to respond to questions about when the final EIS will be issued and whether the hearings will be postponed, a spokeswoman said in an email May 19.

Scout Clean Energy did not respond to a request to comment.

Landowners, including farmers, who would lease land to Scout say rent payments would diversify their income and support their agricultural operations.

Benton County officials, however, are concerned about whether the final environmental impact statement will discuss whether the project will break up farmland, according to their request to EFSEC.

Without the final report out in advance, the hearings will be based on a deficient environmental record and will undermine the recommendation to Inslee, according to the county.

The Yakama tribe made the same complaint, arguing a final report was necessary for an “informed dialogue.”

The tribe asserts the project will destroy wildlife habitat and cultural resources.

Brookfield Renewable, a company owned by Brookfield Asset Management, bought Scout last year.