Duwamish Valley Organizers Appeal Permit Allowing Ash Grove to Burn More Tires

South Seattle organizers are opposing a newly approved permit for a South End cement manufacturing plant to burn more tires for fuel.

The Duwamish River Community Coalition (DRCC), Front and Centered, and Earthjustice filed an appeal on Jan. 2 against the Puget Sound Clean Air Agency (PSCAA) and Ash Grove Cement Company, a national company with a plant on East Marginal Way. The complaint alleges the increase in burned tires will worsen the overall air quality of surrounding residential neighborhoods like South Park and Georgetown. According to a 2023 Department of Ecology report, Ash Grove was the source of the most pollution in South Seattle and South King County.

Ash Grove filed their initial request in April 2020. PSCAA announced its final notice for approval Dec. 5. Ash Grove did not respond to a request for comment. The new regulation goes into effect Feb.3.

PSCAA "determined that this change in tire consumption will not cause an increase in emissions of any regulated pollutant," according to the agency's website.

DRCC's Duwamish Valley Clean Air Program manager Mia Ayala-Marshall said Duwamish Valley residents were "outraged" by the permit's approval.

"They just couldn't believe that our clean air agency would allow one of our industries, that is here in our backyard, to burn more tires," Ayala-Marshall said. "They were just super upset."

Ash Grove has used tire-derived fuel (TDF) that burns whole tires to operate its cement kiln since 1995, in addition to coal and fossil fuels. The facility currently has a 30% TDF daily consumption limit. However, the new permit removes that restriction, based on federal regulatory changes that no longer classify the fuel as solid waste, according to the PSCAA website.

"There's no place in the world where there's no air pollution, so the goal is to keep it as low as possible," University of Washington epidemiologist Anjum Hajat said. "If you're thinking about how you're breathing that in every single day, you can sort of start to see over time how that's going to have negative health effects."

Cement plants emit sulfur dioxide, nitrogen oxide, and carbon monoxide and are considered the third largest source of pollution in the United States. Hajat said researchers believe regularly breathing polluted air can cause inflammatory effects that are seen in a variety of health issues like cardiovascular diseases, cancer, respiratory problems, birth defects, and depression.

The Duwamish Valley, where 65% of residents are people of color and household incomes are among the lowest in the city, is impacted by many air pollution hazards — from numerous industrial sites like Ash Grove to major highways like Interstate 5, State Route 99, and State Route 509, as well as Seattle-Tacoma International Airport and King County International Airport Boeing Field.

"Whereas in other parts of the city, maybe you just have one of those," Hajat said. "You just have a highway, and the further you get from a highway, the better off you are."

The DRCC Clean Air Program was created in 2014 after a study found that the Duwamish Valley was disproportionately affected by socioeconomic, public health, and environmental factors. South Park, Beacon Hill, and Georgetown had the highest number of toxic waste sites in the city and the most severe air pollution next to Eastlake.

The South Park, Georgetown, and Beacon Hill neighborhoods also had the highest rates of childhood asthma hospitalizations in the county, along with Mount Baker and University District.

"These types of revelations really made the community want to understand what was going on and where these health disparities were coming from," Ayala-Marshall said.

After PSCAA announced a draft order of approval in December 2024, DRCC "spearheaded" a campaign to gather signatures and show residents how to participate in the agency's public comment and hearing, Ayala-Marshall said. In November 2025, DRCC held a protest outside PSCAA headquarters in downtown Seattle.

As the appeal moves through the legal process, Ayala-Marshall hopes to use the Clean Air Program to keep centering the voices of the Duwamish Valley community in 2026.

These communities "hold so much of the lived experience of what it means to live in an environmental justice community," Ayala-Marshall said.