County staff and EDF renewables advance lease talks for 3 MW solar project at Wark landfill

Thurston County climate staff and EDF Renewables gave an update on a proposed solar array to be sited on unused portions of the closed Wark landfill.

Rebecca Harvey, Thurston County climate mitigation senior program manager, said county staff executed an option to lease and a right-of-entry agreement with EDF in 2024 to allow site evaluation and that EDF and Puget Sound Energy have negotiated a 25-year power purchase agreement (PPA). "The proposal for a landfill solar project has been has enjoyed support from the board of county commissioners, the public works department, and community members because it is understood and expected to provide several benefits to Thurston County," Harvey said.

Harvey described the conceptual plan as a roughly 21-acre fenced area on unused landfill surfaces intended to host an estimated 3 megawatts AC of fixed-tilt, ballasted PV panels (approximately 7,900 panels). A fair-market-value assessment performed for the county estimated annual lease payments at about $30,000 per year. EDF has completed site-assessment tasks, civil and environmental surveys and is advancing interconnection studies with Puget Sound Energy; county and EDF legal teams are negotiating a long-term ground lease.

EDF representatives clarified technical and economic points during the committee discussion. Battery storage is not part of this project design, EDF said, though utilities including PSE have broader storage goals. EDF explained that lease compensation is normally negotiated as a fixed rent paid to the landowner rather than a revenue-sharing arrangement, which can complicate PPA pricing and project finance.

On geotechnical and design matters, EDF and county staff described a concrete-ballasted racking approach and above-ground wiring so the system does not penetrate the landfill cap. EDF said engineers use geotechnical data to set ballast and gravel pads and that minor localized settling can be managed by adjusting ballast and subgrade rock rather than penetrating the cap.

Harvey said further progress is contingent on final lease terms and permitting; if the parties reach agreement and required permits are obtained, EDF targets construction in 2026. Committee members asked about project lifespan: EDF explained the PPA term is 25 years while equipment lifespan could extend roughly 35 years, and noted potential options for operation beyond the PPA if all parties agree.

Ending: Lease and permitting negotiations continue; staff will update the committee as the county finalizes lease terms, completes required permits and receives EDF's final engineering and interconnection work.