A Small City on Green Bay With a Big Contamination Problem
Marinette, Wisconsin sits at the mouth of the Menominee River on Green Bay, right on the Michigan border. It’s a working-class city of about 11,000 people with a history rooted in lumber, paper, and manufacturing. And since the late 2010s, it’s been dealing with one of Wisconsin’s most significant PFAS contamination events.
The source: Tyco Fire Products, a subsidiary of Johnson Controls International, which has operated a fire protection equipment manufacturing and testing facility in Marinette for decades. The company tested AFFF — aqueous film-forming foam, the type used to fight petroleum fires — at its facility. That foam contained PFAS chemicals. And those chemicals migrated into the groundwater.
How Firefighting Foam Contaminated the Water
AFFF contains PFOS, PFOA, and other PFAS compounds that make it effective at smothering fuel fires. Tyco tested AFFF products at outdoor burn pits and test pads at its Marinette facility. The foam was applied, the fires were extinguished, and the residual foam — laden with PFAS — soaked into the ground.
Over years of testing, PFAS accumulated in the soil and migrated into the shallow groundwater aquifer that feeds private wells in the surrounding area. The contamination plume extends from the facility toward Green Bay, affecting residential neighborhoods along the way.
The Scale of Contamination
Testing has revealed widespread PFAS in Marinette-area groundwater:
- Hundreds of private wells have been tested in the area surrounding the Tyco facility
- Many wells exceeded Wisconsin’s groundwater enforcement standard of 20 ppt for PFOA and 20 ppt for PFOS
- Some wells showed combined PFAS levels in the hundreds or thousands of parts per trillion
- The contamination plume extends to the shoreline of Green Bay, raising concerns about surface water impacts
- PFAS has also been detected in fish tissue from the Menominee River and Green Bay near Marinette
Wisconsin’s PFAS standards have been evolving. The state set recommended groundwater standards for PFOA and PFOS at 20 ppt each, and the DNR has been working to establish enforceable standards consistent with the EPA’s 2024 federal MCLs of 4 ppt.
Tyco’s Response and Remediation
Johnson Controls/Tyco has been conducting remediation under Wisconsin DNR oversight:
- Bottled water was provided to households with contaminated wells as an immediate measure
- Whole-house water treatment systems (granular activated carbon) were installed on affected private wells
- The company drilled monitoring wells across the contamination area to track the plume
- A soil excavation project removed contaminated soil from the former testing areas
- Municipal water connections were offered to some affected residents, connecting them to the City of Marinette’s public water system, which draws from a deeper aquifer not affected by the PFAS plume
- Johnson Controls has committed over $50 million to the Marinette cleanup effort
The remediation is far from complete. PFAS contamination in groundwater moves slowly and persists for decades. Full aquifer restoration, if achievable, will take many years.
Marinette’s Public Water Supply
The City of Marinette’s municipal water system draws from deep wells that tap a confined aquifer, which has been largely unaffected by the PFAS contamination. Testing of the public water supply has shown PFAS levels well below state and federal standards.
However, the contamination underscores the vulnerability of private well users who don’t benefit from public water treatment. In Wisconsin, an estimated 900,000 households rely on private wells, and the state’s PFAS testing programs have found contamination in wells near industrial sites, military bases, and fire training areas across the state.
The Community Impact
PFAS contamination has hit Marinette hard beyond just water quality:
- Property values in affected areas have declined, with homeowners struggling to sell homes with known well contamination
- Health concerns are widespread, particularly among long-term residents who drank contaminated water for years before testing began
- Trust in institutions has eroded, with residents questioning why it took so long for testing to begin and whether the contamination extent has been fully disclosed
- Commercial fishing and recreation on Green Bay face stigma from PFAS concerns, affecting the local economy
What Marinette Residents Should Do
- If you use a private well near the Tyco facility: Ensure your well has been tested for PFAS. If you have a treatment system, verify it’s being maintained. Contact the Wisconsin DNR PFAS program for current information on affected areas.
- Consider connecting to municipal water if the option is available. Municipal supply from the deep aquifer eliminates ongoing PFAS exposure risk.
- Talk to your doctor about PFAS exposure. If you’ve been drinking contaminated water, PFAS blood testing can establish your exposure level and inform health monitoring decisions.
- Stay engaged with the remediation process. Public meetings and DNR updates provide information on cleanup progress and any expansion of the known contamination area.
If you’re concerned about your water quality in Marinette or the surrounding area, a certified water treatment professional can test your water and advise on treatment options appropriate for PFAS removal.
Sources: Wisconsin Department of Natural Resources (WDNR), EPA, Johnson Controls/Tyco Fire Products remediation reports, Wisconsin Department of Health Services