The Tucson City Council is considering banning a specific firefighting foam that contains toxic compounds in an effort to keep it from contaminating more water wells.
The council directed its attorneys to research whether it has the authority to require fire departments, including those on Davis-Monthan Air Force Base and the U.S. Air National Guard base, just north of Tucson International Airport, to immediately stop using the aqueous film-forming foam.
The foam contains per- and polyfluoroalkyl substances that have been found in tainted drinking wells from Tucson’s south side to Marana. The substances are commonly referred to as PFAS.
At least one council member has suggested the city file lawsuits against the U.S. Department of Defense and the state of Arizona, conceding the city may not have the legal authority to stop the use of the foam on state- and federally-controlled land within city limits.
The discussion last week was prompted by the city’s recent release of new well data finding record-high amounts of the toxic and possibly cancer-causing compounds in groundwater in private wells just north of the airport.
The city’s water utility is also spending large amounts of money as it attempts to remove PFAS-contaminated water at eight separate water-treatment plants in the Tucson area, spending nearly $1 million a year to remove the compounds.
City officials note the water sampled is not part of the water delivery system and does not present an immediate threat to the city’s drinking supply.
Councilman Richard Fimbres said he asked for the discussion after seeing the results of recent well testing.
“This council has been transparent and proactive on our water supply,” Fimbres said, outlining council action over the last two decades to address other dangerous chemicals found in some wells controlled by Tucson Water.
In the past, the council has opted to spend the money to build water-treatment plants as soon as the issue was discovered rather than waiting to identify funding sources. Fimbres was referring to finding a carcinogen known as 1,4-Dioxane in the water supply in 2002.
“The mayor and council couldn’t wait and built the (advanced oxidation process water treatment) plant to protect our constituents and our water,” Fimbres said.
Mayor Regina Romero echoed Fimbres’ comments, saying she supports the idea of banning the use of the hazardous foam not only inside the city limits but the entire area that is served by Tucson Water.
“When we found the 1,4-Dioxane, we didn’t wait. We acted immediately, knowing we’d recover the money later,” she said.
Romero said the ban would need to include the Tucson Fire Department, which has a small supply of the foam to use in the event of a particular type of fire — generally involving large amounts of flammable liquids.
Banning the foam is an imperfect solution, concedes Tucson Water Director Tim Thomure, but he stressed the water supplied by the city is safe.
Councilman Steve Kozachik first suggested the ban on the foam during Tuesday’s City Council study session, noting there are other fire departments that have eliminated its use.
“Shutting down wells is not a long-term strategy and no one is pretending that it is,” Kozachik said. “Until we start leading on this thing, we are going to be a little bit complicit ourselves.”
Kozachik suggested the city should sue the state as well as the Defense Department to force the agencies to comply with the ban if it is approved by the council.
“We need to throw down with the DOD and the state and say, ‘You guys are polluting our groundwater,’” Kozachik said. “The litigation takes time, but it is the hook that gets action.”
The city of Tucson and the town of Marana are suing manufacturing company 3M and four other companies that made, marketed and sold firefighting foam that contained PFAS and similar chemical compounds. The lawsuit seeks money to help pay for water-treatment costs.
On Tuesday, it was unclear whether the city has the legal authority to force Davis-Monthan or the Air National Guard to completely stop using the foam.
The council instructed staff to research the issue and report back in January. The city has tested every individual drinking water production well for the compound and have turned off wells with detectable levels that are outside of the city’s water treatment plants. Wells within the range of the treatment plants use specialized filters to remove PFAS.
Thomure said the filters at the plants were not specifically designed to remove PFAS, but work well to remove the compounds.
However, removing the compounds is forcing the city to change carbon filters designed to last between five to 10 years every six months. Between the eight water-treatment plants, the city goes through roughly 16 filters a year, with each filter costing $60,000 apiece.
These are only stop-gap measures, Thomure said, noting the city will eventually need to build new water-treatment plants to better address the PFAS contamination.
Tucson Deputy Fire Chief Joe Gulotta said the department has a limited stock of the foam, but rarely has need to use it. The department is experimenting with other firefighting tools that do not use toxic substances.
The Air National Guard’s Tucson base stopped using a specific version of the firefighting foam that contains PFAS in its fire trucks in December 2016 and in a base hangar in July 2018.
Capt. Aaron Thacker, with the Arizona National Guard, said the guard has taken steps to reduce the use of the dangerous chemical, no longer practicing fighting fires with the foam. The guard has switched to a foam that has trace amounts of PFAS, but would only use the material in the event of a significant fire. Thacker said they are experimenting with other firefighting chemicals that don’t contain dangerous compounds.
Capt. Elias Small, with Davis-Monthan, said that in 2017 the base transitioned to a new formula for its foam that is more environmentally responsible and contains only trace amounts of PFAS and similar chemicals. Davis-Monthan does not use the foam in training and would use it only in the event of an emergency.
“In the event it were to be used, we would take every precaution necessary to mitigate or eliminate the release of (aqueous film-forming foam) into the environment. We are committed to protecting the safety and health of our airmen, their families and Tucson. We will continue to work with our community partners to find a long-term solution,” Small said.
Editor's note: This story was updated to reflect that Davis-Monthan Air Force Base does not use the foam in training.
