Environmental and public interest advocates expressed alarm on Wednesday following the Washington state Department of Ecology’s announcement supporting a new natural gas power plant on the site of the shuttered TransAlta coal plant in Centralia.
In a news release, the Washington Conservation Action wrote that despite significant public health impacts and a pending air quality and environmental review, the project is being actively promoted by Ecology, the agency charged with permitting oversight.
According to previous Chronicle reporting, TransAlta Centralia is expected to begin operations generating power through burning natural gas by 2028 and cease all burning of fossil fuels by a state deadline of 2044. The facility hasn’t burned coal since last year — powering down under an agreement with the state that dates back well over a decade — but the plant has been ordered by the federal government to maintain its ability to generate power through coal.
Ecology released an announcement on Friday, July 31, that the state agency had reached an agreement with TransAlta, a privately-owned corporation headquartered in Alberta, Canada, for environmental mitigation, clearing the way for the Centralia plant to transition to a natural gas-burning power plant.
In recent permit filings, TransAlta, which has owned the plant since 2000, estimates its proposed gas-fired power plant would generate over 2 million metric tons of new greenhouse gas emissions each year. Emissions at that level would bring the plant into close competition with BP’s Cherry Point oil refinery for the title of Washington’s largest stationary source of climate pollution, according to Washington Conservation Action.
Washington Conservation Action also states that the plant would be a major new source of air pollution for the region. Air quality documents filed by the company show that the facility will emit numerous pollutants and air toxics, including volatile organic compounds (VOCs), nitrogen oxides, particulate matter and carbon monoxide, the conservation group stated. These pollutants contribute to ailments including heart and lung disease, asthma, cancer and premature death, and are regulated under the state and federal clean air acts because of their danger to public health and the environment, Washington Conservation Action stated in the release.
Washington Conservation Action claims TransAlta has been the subject of numerous scandals in recent years after being found responsible for electricity price manipulation and paying for favorable research on the community health impacts of coal power plants.
Until last year, TransAlta’s Centralia coal plant was the only remaining coal plant in Washington and one of the largest stationary sources of air pollution in the state. The facility ceased operations in December 2025 as part of a long-planned closure negotiated in 2011. The facility has not generated electricity since its closure, though TransAlta is still seeking recovery of millions of dollars in costs for the plant.
In addition to pollution impacts, Washington Conservation Action claims the project represents a major financial risk for Washington ratepayers. It’s slated to cost much more than the $600 million that has been publicly disclosed, and far above the norm for a similarly sized coal-to-gas conversion project, the group stated in the release. Puget Sound Energy (PSE) has committed to purchasing power from the new plant. However, regulators at the Washington Utilities and Transportation Commission (UTC) have not yet approved the deal, which would lock costs into customer rates for more than a decade, the news release stated.
PSE has included costs for purchasing power from the new gas plant in its current general rate case, in which the company seeks to increase electric rates for customers by nearly 30% over the next three years, a plan that public interest groups oppose.
Additionally, Washington Conservation Action says TransAlta’s permit filings inaccurately compare the proposed gas facility’s future pollution to both the historical coal plant emissions and a hypothetical scenario in which the coal plant kept operating through 2035. Since the plant is not operating (and is expected to be permanently closed), there are no greenhouse gas emissions or toxic air emissions to reduce. In documents that have been shared for public review, Ecology appears poised to cosign this accounting by the company, the news release stated.
Despite being billed to the public and regulators as a “peaker” plant designed to run only during times of electric grid stress, TransAlta is seeking permits that would allow the facility to run at 59% capacity — far above the threshold of a true peaking resource, typically 5 to 15% capacity, and much closer to baseload power plant operation, Washington Conservation Action stated in the release. However, the proposed plant is too inefficient to be permitted as a baseload facility and cannot meet applicable state standards, the group claims.
Public comment on the project’s environmental review documents and draft air quality permit is open through Sept. 15.
"Washington has positioned itself as a global climate leader, but approving this expensive and dirty project as-is would move us squarely in the wrong direction," Julian Santos, climate and clean energy senior manager at Washington Conservation Action, said in the release. "TransAlta is deliberately misleading the public, and state regulators must commit to a robust permitting process to protect the public interest and fully consider the impacts. State agencies must not rubber stamp new fossil fuel plants without due diligence. Washington residents deserve better.”
