The U.S. Air Force is contesting an Environmental Protection Agency order to produce a plan to clean up massive contamination by various PFAS compounds in groundwater underneath two Air Force-owned facilities near Tucson International Airport.
The Air Force and EPA appear headed for a major, potentially prolonged legal struggle over EPA’s authority to require a cleanup plan and whether it’s feasible for the Air Force to produce that plan in EPA’s allotted time period, based on records the agencies released to the Arizona Daily Star on Friday.
EPA issued its 23-page order in late May, citing the federal Safe Drinking Water Act as justification, plus a seven-page statement in July affirming and finalizing the order. The Air Force has sent two responses totaling nearly 40 pages this summer challenging the order.
Probably the most contentious issue is whether pollution underlying the entire airport property represents a major public health threat when currently, nobody is known to be drinking that water.
Because of that, the Air Force says, and EPA strongly disagrees, the pollution doesn’t pose an imminent enough health threat to justify a cleanup plan order.
Beyond that, major differences exist between the Air Force and EPA over whether there’s enough information available about the area’s aquifer and hydrology to develop a good treatment plan, and over whether state and local agencies have done all they could to address the pollution on their own.
The upshot is that several more years may pass before a major cleanup will begin of that airport-area groundwater. It’s been publicly known since 2019 that various PFAS compounds are contaminating groundwater underneath Morris Air National Guard Base near the airport.
Many military facilities across the country used a firefighting foam containing toxic PFAS compounds in the past. The Air National Guard’s Tucson base completely stopped using the foam in 2018, the Air Force previously told the Star.
The EPA’s order also says Air Force Plant 44, along with Tucson International Airport, are also partially responsible for groundwater contamination there. Plant 44 was operated for weapons manufacturing by Hughes Aircraft Co. for several decades and is now operated by Raytheon Missile Systems. It acquired Hughes in 1997.
Tucson Water and Arizona Department of Environmental Quality officials have for years been asking the Air Force to commit to and finance a major cleanup. Both renewed that request in letters to the Air Force this year, Tucson Water in February and ADEQ in May.
One concern expressed by local officials is that the city may have to use that water again if its Central Arizona Project drinking water supplies from Colorado River supplies are substantially cut. Even if a cleanup were to begin next year, it would take many years or decades to finish, meaning the water wouldn’t be available for public use for that long. A cleanup is also likely to cost tens or hundreds of millions of dollars, city officials have said.
The Air Force continues to say it first needs to finish a separate detailed, remedial investigation being conducted under the federal Superfund toxic waste cleanup law.
“We believe a science-driven, and data-informed approach is necessary to address the PFAS challenges in the Tucson region,” said Michelle Brown, a top Air Force environmental official, in a statement sent last month to EPA.
“This process needs to involve all potentially responsible parties — and, to this end, we proposed pausing your enforcement actions to allow all stakeholders (and their technical experts) to engage in a collaborative forum or technical working group.”
To evaluate any potential regional solution, a “multi-disciplinary technical team from EPA, ADEQ, the City of Tucson, Tucson International Airport, and other responsible parties” is needed to share all available data, identify additional data needed to complete modeling of the area’s hydrology, develop a plan to collect missing data and conduct additional computer modeling of the area’s hydrology, the Air Force said.
‘Their contamination to our well field’
Based on the Air Force’s recent comments to EPA, Steve Kozachik, a former Tucson city councilman long active in the PFAS issue, worries it could be five more years before a major cleanup will begin.
He cited a boldfaced Air Force statement in a response to EPA that another recent EPA decision setting drinking water limits for PFAS compounds gives public drinking water systems until 2029 “to implement solutions to reduce regulated PFAS in supplied drinking water.”
“We’ve already used a significant amount of taxpayer resources trying to manage their contamination to our well field, all without the Department of Defense at the table ready to ante up cash to assist,” Kozachik told the Star Friday.
“In their letter they’re asking for grace until 2029, assuming the (PFAS) plume will wait on their process, and that our CAP allocations will be fine until then and our reliance on groundwater is status quo for another five years. Both assumptions are bull——,” he said.
“The plume isn’t waiting on their process, and no thinking person believes the threat to the Colorado (River) is not something we should be addressing yesterday. Not in 2029.”
In one of its statements, however, the Air Force said EPA’s order “will not and cannot result in the elimination of PFAS contamination” from the aquifer any faster than an ongoing, separate process the Air Force has been involved in for several years under the Superfund law.
The Air Force has told the Star it’s designing and intends to launch operation of two pilot treatment projects in the airport area in a couple of years. But in an interview Friday, the Air Force’s Brown said that before beginning a major cleanup, it wants to finish conducting a major, computer model-based study of PFAS contamination in the broader Tucson area including areas outside the airport.
“We’ve got a complicated hydrology out there. We want to make sure that whatever remedy is selected is the right remedy,” said Brown, the Air Force’s principal staff advisor on environmental programs. “We will be using significant taxpayer resources. We want to make sure we are as accurate as possible.”
Brown couldn’t immediately respond to a question from the Star about how long it will take to finish that study, which has been going on for about a year. She said the Air Force will respond later.
In a statement to the Star, the Air Force noted the EPA order doesn’t mandate that other potential sources in that area provide information on their PFAS releases, and “that information is needed to address the significant data gaps” in the airport area.
But “EPA cannot wait for any and all alleged data gaps to be filled,” EPA wrote last month in response to an Air Force statement challenging its authority to require the plan.
It’s common to devise an interim response to contamination based on the currently available information, and that response may be revised as more detailed information becomes available, EPA said.
Three issues EPA, AF disagree on
EPA issued what it called an emergency order to the Air Force on May 26 to produce the cleanup plan in 60 days.
The Air Force first told EPA on June 24 that it believes the environmental agency lacks authority to issue such an order and it’s not possible to meet the time schedule. On July 11, EPA issued a final decision affirming its order, rebutting the Air Force’s comments and extending the compliance deadline 30 days.
Then, on Thursday, the Air Force sent a formal request to EPA to withdraw the order.
Here’s a summary of three issues separating the agencies:
Public health endangerment. In its original order, EPA said potential drinking water exposure to PFAS compounds at levels exceeding drinking water limits “may present an imminent and substantial endangerment to the health of persons.”
It cited concentrations of five PFAS compounds found to be far exceeding drinking water limits in groundwater under the two Air Force facilities, Tucson International Airport and the aquifer north of those areas. It noted that the contamination from PFAS and other chemicals has shut down five city wells. It said existing city efforts to hold down PFAS concentrations in water feeding its treatment plant are “not sustainable.”
The Air Force, responding, besides noting people aren’t drinking the contaminated water, cites the success of the city‘s south-side Tucson Airport Remediation Project water treatment plant at removing PFAS, trichloroethylene and 1,4-dioxane from groundwater in that area. It notes, “It is undisputed that the TARP-treated water meets all drinking water standards.”
“There is no threat, ‘imminent’ or otherwise, to the public from the treated water,” the Air Force said.
EPA’s own cleanup guidelines recognize that the purposes of such an action “are to prevent an impending dangerous condition from materializing, or to reduce or eliminate a dangerous situation once it has been discovered,” Air Force attorneys wrote on June 24.
Also, EPA guidelines say “such actions should not be used in cases where the risk of harm is remote in time or completely speculative in nature,” the Air Force wrote.
EPA, however, said in its July 11 final order, “Actual service or consumption of the water is not a prerequisite to use of the authority” to order a cleanup. EPA also notes that “the water was being served prior to the discovery of PFAS and would still be served but for the current PFAS contamination.”
That water remains a “vital component of Tucson’s portfolio of drinking water sources,” EPA added.
“Tucson is in the desert and other sources of drinking water have been dramatically reduced. The law does not require EPA to wait for the next severe drought or another even more significant reduction in other drinking water sources such as the Colorado River,” EPA said.
City and state PFAS cleanup actions. To help treat the PFAS-tainted water, Tucson and the Arizona Department of Environmental Quality have obtained $25 million in federal money to design and build a new treatment plant at the site of the existing south-side plant to remove PFAS compounds from water coming into the plant. The new treatment plant, using a different and what officials say will be a more effective technology for PFAS removal, is slated to start operations in 2027, Tucson Water says.
While EPA supports this and other steps state and local officials have taken to address the pollution, it says “Arizona and the local authorities have not acted sufficiently to address all measures covered under this Order that are necessary to protect the health of persons.” This is underscored by the endorsement of EPA’s original order by ADEQ and Tucson, EPA said.
The Air Force, however, said Tucson’s TARP plant’s ability to successfully treat contaminated water to fully meet all applicable drinking water standards shows the local agency is taking sufficient action.
It uses both advanced oxidation and granulated carbon to treat other contaminants in the water, and both of them also remediate PFAS compounds, the Air Force said.
The Air Force also cites the city’s planned new $25 million treatment facility as an example of how the city’s actions toward PFAS are adequate.
EPA’s order doesn’t identify any specific measures that local authorities have not taken, the Air Force said.
“Instead, EPA is ordering the Air Force to do what local authorities are currently doing: a long-term water treatment method to ensure water extracted from the TARP well field meets federal drinking water limits to allow for the TARP water to be used for drinking,” the Air Force said.
Feasibility of EPA cleanup plan deadline. Preparing a plan in 60 to 90 days isn’t possible, the Air Force says, noting “Addressing PFAS in groundwater is a complicated issue.”
The longstanding federal Superfund toxic waste cleanup site that includes the two Air Force facilities is an industrial area.
And, “in addition to known PFAS releases from Air Force Plant 44, Morris Air National Guard Base, and the airport, available data indicates PFAS has also been released from other sources, and sampling has not even begun in some of these areas,” the Air Force wrote EPA on June 24.
“Significant data gaps remain at numerous areas, including for example, the airport, especially the wash, Three Hangers, Runway 3, Texas Instruments, and West Cap areas,” the Air Force said, noting other industrial facilities located in the airport vicinity.
Plus, the site’s hydrogeology is highly complex, and data suggests that different plumes are contributing to the contamination at the north and south ends of where city wells are now feeding the existing water treatment plant, the Air Force said.
“There are three major aquifers underlying the area with varying transmissivity and hydrologic connections. Preliminary data indicates that surface water transport is another major pathway for PFAS migration in this area. All of these factors are poorly understood,” the Air Force said.
But EPA attorneys countered on July 11, “With respect to imminent and substantial endangerment to the health of persons, EPA cannot wait for any and all alleged data gaps to be filled. … Instead, the Air Force must submit the required PFAS Water Treatment Plan promptly and proactively protect the City of Tucson’s drinking water supply.”
Concluding its July 11 response, EPA doubled down on its view that its order is supported by the facts and the law and “is necessary and directs appropriate actions to address the conditions of PFAS contamination to which the respondents significantly contributed.
“The Air Force’s prompt compliance in this matter will send a strong message that the Air Force is committed to ensuring that the people of Tucson have an adequate and safe drinking water supply.”
