The Energy Facility Site Evaluation Council has rescheduled a vote on the Horse Heaven wind and solar project in southeast Washington for 8 a.m. Wednesday, Sept. 4.

The meeting will be online. The council postponed a vote set for Aug. 29 because one member was absent.

EFSEC went ahead with an hourlong discussion on the proposal by Scout Clean Energy to place up to 222 turbines and more than 5,000 acres of solar panels on rolling hills near the Tri-Cities.

EFSEC last spring recommended Gov. Jay Inslee permit the project, but with restrictions on placing turbines and solar panels that Scout complained would cut the installation’s maximum 1,150-megawatt output by half.

Inslee rejected EFSEC’s recommendation and asked the council to restore the project’s proposed capacity to help the state meet its need for renewable energy.

Based on council discussions since May, EFSEC planners have prepared a new recommendation. It’s unknown, however, how far the new recommendation would go in restoring the power output envisioned by Scout.

EFSEC has reduced to 0.6 mile from 2 miles a hard buffer around 63 historic Ferruginous hawk nests. The larger buffer potentially eliminated 107 turbines. The smaller buffer eliminates 12 turbines.

EFSEC planners, however, are recommending 2-mile buffers around an undetermined number of nests that are “available” and habitat that is “viable.”

Wildlife experts on an advisory group would help EFSEC define “available” and “viable,” EFSEC planner Sean Greene told the council. “That process is certainly going to be involved,” he said.

Based on the advisory group’s recommendations, EFSEC probably would end up nixing more than 12 turbines by stretching the buffers to 2 miles, Greene said.

“It’s almost certainly going to go up,” he said. “How much it’s going to go up is still to be determined.”

Scout CEO Michael Rucker said in an Aug. 25 letter to EFSEC that uncertainty over the project’s layout and the definitions of “available” and “viable” was unacceptable.

He accused EFSEC of shirking its duty to approve a final layout. He also called on Inslee to override EFSEC if necessary, an idea rejected by the governor’s office as beyond his authority to edit recommendations.

EFSEC Chairwoman Kathleen Drew defended using a pre-construction advisory group to birddog the project’s design and to respond to unanticipated impacts. EFSEC will make the final decisions on buffers, she said.

As currently drafted, the new recommendation assigns Scout the leading role in establishing the advisory group, recruiting members and running meetings.

The recommendation does not dictate the group’s makeup. Members could be drawn from state agencies, tribes, landowners and local-interest groups.

The Washington Department of Fish and Wildlife recommended 2-mile buffers around all nests. No hawks are nesting in the area now, but hawks can reoccupy nests after many years, according to state biologists.

Besides encouraging the return of the hawks to the Horse Heaven Hills, the hard 2-mile buffers reduced impacts to views and Yakama Nation tribal culture.

The new recommendation prohibits windmills within 1 mile of Webber Canyon, a site important to the tribe. The tribe remains opposed to the project.