Joanne Stanton grew up in Warminster, Pennsylvania, in a neighborhood where kids rode bikes past the perimeter of the Naval Air Development Center and nobody thought twice about the occasional plume of white foam drifting from the base. The foam was AFFF — aqueous film-forming foam — a firefighting agent the Department of Defense had used since the 1970s to extinguish jet fuel fires. It was effective, reliable, and laced with PFAS, a family of synthetic chemicals that do not break down in the environment.
Stanton didn't learn any of this until 2014, when her world fractured. Her oldest son had been diagnosed with a cancerous brain tumor at age six. Years later, testing revealed that the drinking water she and her family had consumed for decades was contaminated with PFOS and PFOA — two of the most studied and dangerous PFAS compounds — at levels hundreds of times above what the EPA would eventually deem safe.
"My exposure may have actually caused cancer in my child," Stanton told Community Action Works. It was the kind of sentence no parent should ever have to say — and it became the spark that lit a movement.
The Scale of Contamination
The contamination didn't come from one base. It came from two: the former Naval Air Station Joint Reserve Base Willow Grove (now Horsham Air Guard Station) in Montgomery County, and the former Naval Air Development Center in Warminster, Bucks County. Both had used AFFF extensively for fire training exercises over decades, and both sat atop the same regional aquifer that supplied drinking water to Horsham, Warminster, and Warrington townships — a combined population of roughly 70,000 people.
In 2014, the EPA's Unregulated Contaminant Monitoring Rule (UCMR3) program detected PFAS in five of the fourteen wells operated by the Horsham Water and Sewer Authority (HWSA). The numbers were staggering. Well #26 tested at 700 parts per trillion (ppt) for PFOS and 290 ppt for PFOA. Well #40 came in at 1,000 ppt for PFOS alone — five times the EPA's then-provisional health advisory of 200 ppt.
Those two wells were shut down immediately. But the problem was far larger than two wells. By 2015, testing at a detection threshold of approximately 2.5 ppt revealed PFAS contamination in all fourteen HWSA wells and one interconnect supply. The aquifer itself was compromised.
In 2016, when the EPA lowered its health advisory to a combined 70 ppt for PFOA and PFOS, three more wells — #10, #17, and #21 — were taken offline. The Horsham Water and Sewer Authority, which had relied on groundwater for roughly 90 percent of its supply, was suddenly scrambling to replace nearly half its production capacity.
The Private Well Crisis
Public water systems, for all their vulnerabilities, at least get tested. Private wells do not. And in the townships surrounding the two Navy bases, hundreds of families drew their water from private wells with no monitoring, no treatment, and no idea what was in their water.
Under pressure from the EPA and state regulators, the Navy eventually sampled 511 private wells in the affected area. The results confirmed the worst fears: 97 wells exceeded the 70 ppt health advisory, and another 60 fell in a gray zone between 40 and 70 ppt — levels considered concerning enough to warrant quarterly monitoring. Some private wells near the bases tested as high as 5,000 ppt for PFOS, more than 1,250 times the EPA's current maximum contaminant level of 4 ppt.
For families on those wells, the contamination wasn't abstract. It was in every glass of water, every pot of pasta, every bath their children took. And for many, it had been for years — sometimes decades — before anyone thought to test.
Two Mothers Build a Movement
Joanne Stanton and Hope Grosse had grown up in different parts of the same contaminated landscape. Grosse lived near the Warminster base; Stanton near Willow Grove. Both had raised families on the local water. Both had health scares that, in retrospect, aligned disturbingly well with known PFAS health effects — thyroid disease, reproductive complications, cancer.
In the years following the 2014 discovery, the two women co-founded the Buxmont Coalition for Safer Water, a grassroots organization dedicated to research, education, and advocacy for residents of Bucks and Montgomery counties coping with PFAS exposure. Grosse also became a CERCLA (Superfund) oversight representative for the Warminster cleanup, embedding community accountability directly into the federal remediation process.
Their work was unglamorous and relentless: organizing public meetings, compiling health data, pressuring the Navy and EPA for faster action, and testifying before Congress. In Senate testimony, Stanton told lawmakers: "Seven years ago, my community of Warminster was devastated to discover that our drinking water had been highly contaminated with PFAS for 50 years."
Alongside the coalition, state Senator Maria Collett (D-12) of Lower Gwynedd championed the cause in Harrisburg, pushing for state-level PFAS standards and increased funding for water treatment infrastructure. The political alignment of grassroots activism and legislative advocacy proved critical.
What Remediation Looks Like
The Horsham Water and Sewer Authority's response became a case study in municipal resilience under pressure. With five wells offline and every remaining source contaminated, HWSA installed granular activated carbon (GAC) filtration systems — the gold standard for PFAS removal — on its active wells. The Pennsylvania Department of Environmental Protection issued a standard operating procedure in 2018 requiring treated water to meet stringent benchmarks, including arsenic levels below 1 part per billion post-GAC treatment, since the carbon filters can release naturally occurring arsenic from the local geology.
HWSA also built 1.8 miles of new water mains to connect private well users to the public system, giving contaminated households an alternative source. The Navy funded carbon filters for private wells that exceeded the 70 ppt health advisory and continued quarterly monitoring for the 60 wells in the gray zone.
These were meaningful interventions. But they were also expensive, slow, and incomplete. GAC filters require regular replacement — the carbon becomes saturated with PFAS and must be disposed of as contaminated waste. Each well that goes through a filter changeout can be offline for days to weeks. And the fundamental problem — PFAS in the aquifer — remains unsolved. Filtration treats the symptom. The contamination persists.
The Blood Doesn't Lie
In August 2025, the CDC's Agency for Toxic Substances and Disease Registry (ATSDR) released results from a national PFAS Exposure Assessment study that included residents near military bases like Willow Grove and Warminster. The findings were sobering: approximately 100 percent of tested residents living near contaminated sites had elevated blood levels of PFAS, and roughly 30 percent had concentrations high enough to warrant ongoing medical monitoring.
The health effects linked to PFAS exposure at these levels include elevated cholesterol, thyroid dysfunction, liver damage, reproductive complications, immune system suppression, and increased risk of certain cancers — including kidney cancer and testicular cancer. For residents like Stanton, who watched her son fight a brain tumor, the data confirmed what she had long suspected: the water hadn't just been contaminated. It had been dangerous.
A Federal Standard — Finally
In April 2024, after nearly a decade of advocacy from communities like Horsham, the EPA finalized its first-ever enforceable national drinking water standards for PFAS. The rule set maximum contaminant levels (MCLs) at 4 ppt for PFOA and 4 ppt for PFOS — a dramatic tightening from the 70 ppt health advisory that had governed response efforts since 2016.
For the Buxmont Coalition, it was a hard-won victory. Local news outlet Bucks County Today reported that Stanton, Grosse, and Senator Collett celebrated the milestone as validation of nearly ten years of advocacy. But the victory came with caveats: water utilities nationwide now face billions of dollars in compliance costs, and the question of who pays — the military that caused the contamination, the manufacturers who sold the foam, or the ratepayers who drank the water — remains unresolved in most communities.
In Horsham, the answer has been a patchwork. The Navy funds some remediation and private well testing. The water authority absorbs treatment costs that get passed to ratepayers. And the community continues to live on top of an aquifer that will carry PFAS for generations.
What Horsham Teaches Us
The Horsham story is not unique — there are hundreds of military bases across the country with similar AFFF contamination histories. But Horsham stands out for the clarity of its narrative: a known source, a documented contamination pathway, measurable health impacts, and a community that refused to accept silence as an answer.
What Joanne Stanton, Hope Grosse, and the Buxmont Coalition demonstrated is that accountability doesn't happen by accident. It happens when affected people organize, demand data, and refuse to let regulators treat contamination as someone else's problem. Their advocacy directly contributed to the national PFAS drinking water standard that now protects every American served by a public water system.
At EPR Foundation, we believe this is how environmental protection actually works — not through abstract policy debates, but through communities that stand up, document the harm, and demand that the systems built to protect them actually function. Horsham's water is cleaner today because its residents fought for it. The question now is whether we can build systems that catch the next contamination before 70,000 people have been drinking it for decades.
Sources
Horsham Water & Sewer Authority, "PFAS Response Timeline and Well Data," AAEES/NJWEA Presentation, May 2019. • ATSDR, "PFAS Exposure Assessment — Region 3 Site Profiles," 2025. • Community Action Works, "Decades After Contamination: Hope and Joanne's Story." • Bucks County Today, "EPA Introduces Strict PFAS Water Contamination Standards," April 2024. • WHYY News, "U.S. Court Ruling Opens Door to More Suits Over Contaminated Water Supplies." • Buxmont Coalition for Safer Water, buxmontwater.org. • U.S. Senate Committee on Environment and Public Works, Testimony of Joanne Stanton. • EPA, "Horsham Community Engagement Report," November 2018.