The Washington State Department of Agriculture says solar installations will damage soils, disputing a claim by an energy company that 1,000 acres of prime farmland in Klickitat County could revert to agriculture in 25 years and be as productive as before.

Agriculture department policy adviser Kelly McLain said Jan. 24 in an email to the Energy Facility Site Evaluation Council that the proposed Carriger solar project near Goldendale would compact and shade ground, depriving it of sunlight and organic material.

The soil may need decades to recover after the solar panels and posts are gone, she stated. “Even with decommissioning, WSDA does not expect the ground to meet pre-project agricultural viability.”

The project’s developer, Cypress Creek Renewables, based in Santa Monica, Calif., disagrees with WSDA’s assessment and rejects McLain’s suggestion that soils be regularly tested.

The solar panels will rotate to follow the sun, exposing the ground to sunlight. Hard surfaces will cover 40 acres and the rest will be undisturbed or planted with low-growing vegetation, according to the company.

“Because we do not anticipate widespread soil compaction or long-term impacts to soil health in regard to future farming practices, Cypress Creek does not see the need for soil sampling,” company spokeswoman Angeli Chandler said in an email.

Cypress Creek is owned by EQT Infrastructure, an investment firm based in Stockholm.

The company estimates the 1,326-acre solar project would last 25 to 40 years. The land has 634 acres of wheat; 358 acres of hay, including 70 irrigated acres; and 179 acres of pasture, according to Cypress.

More than 93% of the land is classified as “prime farmland” or “farmland of statewide significance,” according to the agriculture department.

Soil tests would document the degradation of the soil and suggest what needs to be done to restore the ground for agriculture, McLain said in an interview.

“Without data, we don’t know how much damage they’re causing,” she said. “I don’t feel like we’re asking a lot.”

Decommissioning plans

Several Eastern Washington counties are concerned about permanently losing farmland to solar projects, even though companies are required to have plans to restore the land to its pre-project condition.

Energy companies must file an “initial” decommissioning plan before starting construction. A “detailed” decommission plan is not due until the company is ready to start demolishing the project.

Companies will have to do more than remove the panels and posts and fill the holes, McLain said.

“The project impact is not short term or transitory in nature because not all damage will be remediated at the point of decommissioning,” she said.

EFSEC has yet to do a study on the project’s potential environmental impact. EFSEC reviews renewable energy projects and submits recommendations to Gov. Jay Inslee.