A federally funded project to treat man-made forever chemicals has been completed at the Tucson Airport Remediation Project facility.
At a ribbon-cutting event Tuesday, dozens of local water stakeholders, elected officials and community members applauded the completion of the project, which is designed to improve the treatment of per- and polyfluoroalkyl substances, otherwise known as PFAS.
“We’re very fortunate that Tucson Water is being proactive instead of reactive,” said Yolanda Herrera, a community co-chair of the Unified Community Advisory Board for the Tucson International Airport Area Superfund Site.
In 2022, the Arizona Department of Environmental Quality awarded Tucson Water $25 million from the Biden-era American Rescue Plan Act to improve treatment of forever chemicals, a group of manufactured chemicals that are tied to cancer and other health problems.
The Tucson Water system has about 40 wells that have been affected by PFAS, 30 of which are located in and around the city and have been turned off or put in emergency standby status as PFAS was detected over the last decade, according to John Kmiec, Director of Tucson Water.
The other 10 wells that were affected are part of the TARP and have been treated and discharged into the reclaimed water system on the Santa Cruz River.
“This expansion also protects and restores critical local groundwater resources, further diversifying Tucson’s water supply portfolio and strengthening system reliability during drought, shortage and other supply disruptions,” Kmiec said.
Kmiec said that if water testing results yield positive results, Tucson Water could present them to the mayor and council to see if the treated water should return back into the drinking water system.
“There’s no crisis or necessity to bring the TARP water back to the drinking water system,” Kmiec said. “That can be done slowly, methodically with the community support and impact if they want to do that in the future and it’s because we have such a diverse water portfolio.”
In 2021, Tucson Water temporarily shut down the TARP due to the rising levels of PFAS in the groundwater wells serving the plant, taking that treated water out of the drinking water supply.
During Tuesday’s event, Governor Katie Hobbs praised Tucson for bolstering its water portfolio amid ongoing negotiations over the Colorado River’s future.
“You can’t talk about water conservation without talking about Tucson,” Hobbs said. “This expanded TARP facility is a testament to what we achieve when we refuse to wait for someone else to solve our problems.”
Historic contamination
The TARP facility has been around since 1994.
The facility was constructed to initially treat a portion of the aquifer that was contaminated by the industrial solvent trichloroethylene, or TCE, that was used by Hughes Aircraft to clean airplanes at the Air Force Plant 44 in the 1950s and improperly disposed of until the 1980s.
In 2014, Tucson Water began its treatment of 1,4-dioxane, a stabilizer in industrial solvents in aircraft manufacturing facilities that was used from the 1940s to the 1970s.
Michael Montgomery is the director of the Superfund and Emergency Management Division for the U.S. Environmental Protection Agency for the Pacific Southwest.
He said that 64 billion gallons of contaminated water have been treated and 6,800 pounds of TCE have been removed at the TARP facility.
“As we approached the promulgation of a federal drinking water standard for PFAS and another rulemaking that made it a hazardous substance, we worked very closely with Tucson Water so that we were ready,” Montgomery said. “To help (the city) as best as we could, the city to deal with this new challenge which is plaguing communities across our nation.”
In 2024, the EPA called on the U.S. Air Force and Arizona Air National Guard to address the threat to human health by PFAS at the Tucson Superfund Site, including the TARP water well field.
In a letter to the EPA, the Air Force also said it was willing to enter into an interim settlement agreement with the City of Tucson and Tucson Airport Authority, agreeing to cover 50% of past water treatment plant costs and 50% of future pre-treatment plant costs after federal ARPA dollars are used.
President Trump's EPA
In May, the EPA announced its plan to roll back regulations for several types of PFAS that were introduced in 2024 under President Biden that required community water systems to monitor and reduce the levels of PFAS and notify the public of any exceedances.
It was the first time the agency set an enforceable national drinking water standard.
The EPA is proposing to extend the compliance dates for the PFOA and PFOS Maximum Contaminant Levels to 2031.
In July, Attorney General Kris Mayes and other attorneys general opposed the EPA's plans to rescind its regulations for four PFAS substances.
