Construction of a controversial lithium-ion battery storage system in Rochester can now go forward, the Thurston County Hearing Examiner decided this week.
The new decision, issued March 9, comes after Hearing Examiner Sharon A. Rice denied special use permits for the proposed 5.4-megawatt lithium-ion battery energy storage system (BESS) at 7505 183rd Ave. SW in Rochester on Nov. 10. The applicant, Convergent Energy & Power, appealed the decision.
The facility is intended to address possible rolling blackouts and other reliability issues as the demand for electricity in the Rochester area continues to grow, according to Convergent.
Rochester residents largely opposed the proposal, with 13 citizens testifying in person during the hearing on Oct. 14. Nearly 100 additional public comments, including letters from local tribes and the West Thurston Regional Fire Authority, were submitted between Jan. 2 and Oct. 20.
An additional 55 public comments were submitted after Rice granted Convergent Energy & Power’s request for reconsideration on Dec. 2. At that time, the record was reopened to receive new evidence on fire and life safety, groundwater impacts and compatibility with the rural surroundings and rural character of the facility.
Primary concerns from the public include the risk of fire associated with lithium-ion batteries and the attendant public health and environmental risks if a fire were to occur, including degradation of air and water quality.
In her initial Nov. 10 decision, Rice found that the proposed facility would “impose an undue burden on the local fire district,” West Thurston Regional Fire Authority; was not consistent with the purpose of the rural commercial center zone; would not meet the everyday needs of the community; and would not be functionally and visually compatible with the surrounding rural area.
“As supplemented at the reconvened hearing on reconsideration, the record as a whole demonstrates that, as conditioned, the special use can be appropriate operated in the location proposed,” Rice states in the new decision.
Upon reconsideration, Rice found that the proposed BESS facility is “similar in nature and impact” to industrial uses allowed in Thurston County code, and is allowed under county code provided it generates fewer than 220 pounds of hazardous waste per month.
“While the surrounding community remains understandably concerned about the fire risk associated with LFP lithium-ion battery installations, the record on reconsideration addresses these concerns more credibly and in more detail than was provided at the October 2025 hearing,” Rice states in her March 9 decision.
For example, Rice stated, current fire codes at BESS facilities “contain provisions addressing many of the previously unaddressed hazards.”
There are still hazard mitigation plans regarding fire safety and groundwater contamination that need to be worked out before the BESS facility goes online, but “Due to their technical nature, it is not with the Examiner’s authority to determine the adequacy of the required plans,” Rice stated.
Rice did make the acquisition of those hazard mitigation plans conditions of the special permit approval.
Conditions include:
• Convergent Energy & Power must collaborate with West Thurston Regional Fire Authority to create an emergency operations plan that includes incident response protocols, emergency contact procedures, and site-specific firefighting tactics. The plan must be submitted prior to final building inspection.
• Convergent Energy & Power must submit a fire safety compliance plan, signed and sealed by a fire protection engineer licensed within Washington state, that demonstrates compliance with fire codes regarding thermal runaway prevention, ventilation and spatial separation.
• West Thurston Regional Fire Authority must conduct at least one pre-incident planning walk-through and training session for responding personnel, including explanation of system layout, shut-down procedures, access routes, and water supply.
• A third-party hazard mitigation analysis assessing thermal event propagation, adjacent equipment interaction, toxic gas release and code compliance must be submitted and approved before final building inspection.
• To the extent possible, post-incident remediation must include a plan to ensure that stormwater does not come into contact with post-fire debris. If contaminated stormwater does flow into the nearby bioinfiltration facility, amended soil must be tested.
• A decommissioning plan must be submitted before final inspection and approval.
Rochester citizens with ongoing safety concerns about the facility have appealed Rice’s most-recent decision.
To learn more about the proposal, visit the county’s hearing examiner page at https://tinyurl.com/ywcxnwwx.
