By Jan Axelson
Northside News
This is the second in a 3-part series that focuses on PFAS, a class of human-made chemicals found in our waters and in many everyday items. You will learn where PFAS are found, how they can be harmful to human health and the environment, and how to protect your health by reducing your exposure to PFAS.
The group of chemicals known as PFAS, or “forever chemicals,” have strong chemical bonds that resist breaking down. Studies show that PFAS can contribute to health issues such as cancers, high cholesterol, high blood pressure in pregnant women, low infant birth weight, decreased fertility for women, interference with hormones, and reduced response to vaccines.
Part 1 of this series explored the presence of PFAS in everyday items such as cookware and cosmetics. Another major use of PFAS is in fire-fighting foam. Use of the foam by the Dane County Regional Airport has resulted in PFAS pollution in our local waters, leading to health advisories for fishing and other water recreation.
PFAS in firefighting foams
Firefighting foam containing PFAS works by forming a film that cuts off oxygen and keeps flammable vapors from escaping. (Household fire extinguishers typically use dry chemical powder or carbon dioxide and are unlikely to contain PFAS.) While airport fires may be rare, training activities with foam can put large amounts of PFAS on the ground. Storm water can then carry PFAS into nearby streams, lakes and other waters.
The airport receives its firefighting services from the Wisconsin Air National Guard based at Truax Field in the southeast corner of the airport. The use of PFAS at the airport likely began in the early 1970s.
A former training site is located north of Darwin Road between International Lane and Starkweather Creek, just south of the airport’s cell phone parking lot. Sometimes referred to as a “burn pit,” the site was an open area where training activities occurred, including putting out fires with PFAS foam. The site hasn’t been used since 1986, but the ground remains polluted.
PFAS in our waters
If you fish, swim, paddle, or recreate in other ways in or around local waters, you want to be aware of how to keep from exposing yourself to harmful levels of PFAS.
The biggest source of PFAS in local waters is Starkweather Creek. The West Branch flows in ditches along the north and west ends of the airport, past the burn pit, and continues south toward Lake Monona. The East Branch follows Fair Oaks Avenue and joins the West Branch in O.B. Sherry Park, about half a mile upstream from the lake. The combined creek empties into the lake at Olbrich Park on Madison’s east side.
In summer 2024, with support from the national Sierra Club, volunteers from the Friends of Starkweather Creek surveyed 20 waterbodies in Dane County to measure levels of PFAS chemicals. The goal was to learn if PFAS were still flowing from the foam used by the airport into Starkweather Creek and the downstream Yahara Lakes.
To protect human health, Wisconsin has set standards, or limits, for PFOS and PFOA in surface waters where people recreate, including fishing. PFOS and PFOA are two of the most widely used and most studied PFAS chemicals. Waters that measure above the limits are considered impaired. Drinking water has stricter standards than surface-water standards.
In Starkweather Creek just below the airport, the study measured PFOS levels 245 times above the surface-water limit, and PFOA levels were more than twice the limit. Downstream in the West Branch and where the two branches combine, PFOS levels remained well above the limits. In Lake Monona, Lake Waubesa and Lake Kegonsa, PFOS levels were slightly above the limits.
Locations with PFAS levels below the limits included Lake Mendota, Starkweather Creek’s West Branch upstream from the airport, Starkweather Creek’s East Branch, Nine Springs Creek, Black Earth Creek, Indian Lake, Fireman’s Park Beach in Verona, and Stewart Lake Beach in Mt. Horeb.
Other locations with levels below the state limits were the Wisconsin River and water flowing into Badfish Creek and Badger Mill Creek from the two Madison Metropolitan Sewage District outfalls.
Staying safe in and around the water
Fish absorb PFAS in water, and there is no known way to remove PFAS from fish before eating them. The Department of Public Health Madison & Dane County provides guidelines for limiting the amount of fish consumed from local waters with PFAS. (See table.)
Wind and current can cause patches and areas of foam to form in water. The foam may be from a natural source such as decaying leaves or from human-made chemicals, including PFAS. Christy Remucal, interim director of the University of Wisconsin Aquatic Sciences Center, led a recent study of foam in Wisconsin rivers and lakes and found that foams contained much higher concentrations of PFAS than the water below them.
The Wisconsin Department of Health Services recommends that everyone, including pets and young children, avoid surface-water foams. Even foam from natural sources can contain high amounts of algae, viruses, bacteria, parasites and other contaminants that can be a health risk if swallowed.
If you contact foam in water, use soap and clean water to wash your hands and other body parts that were in contact with the foam, especially any areas with open wounds. Rinse pets with clean water, and bring clean drinking water for pets.
Ending PFAS use at the airport
For many years, Federal Aviation Administration (FAA) regulations required airports to use a firefighting agent containing PFAS for emergencies. In 2023, a PFAS-free foam was approved for use. In September 2024, the Guard at Truax announced they had completed the transition to PFAS-free foam in firefighting trucks servicing the airport.
While the new foam doesn’t contain PFAS, studies suggest more research is needed on the foam’s impact on human and environmental health, including aquatic life.
FAA regulations require vehicle fire-system testing once a year. In 2019, the FAA began allowing airports to use testing equipment that doesn’t require any dispensing of foam. The Guard uses this equipment.
Removing PFAS from the land
The Wisconsin Department of Natural Resources has identified Dane County, Madison and the Guard as the parties responsible for removing the existing PFAS contamination at the airport. Possible solutions include removing the contaminated soil and disposing of it offsite or burning at high temperature. These methods would be very expensive and hard to do.
As an alternative, the Dane County Board has approved funding for a new approach offered by ORIN Technologies in Verona and a Canadian partner. The method uses microbes injected into the soil to break down the PFAS and a carbon sponge to absorb the resulting chemicals. While a test run appeared to show success, whether this method will work on a larger scale remains to be seen.
In February, the Dane County Board passed a resolution to release a deed restriction on land near the airport. The resolution included a provision that funds resulting from the release will be used for cleaning up PFAS contamination.
Learn more
Friends of Starkweather Creek, stark
weatherfriends.org
Dane County Regional Airport PFAS Information, msnairport.com/about/ecomentality/PFAS-Information
Wisconsin National Guard PFOS/PFOA Information Page, wi.ng.mil/Resources/PFAS
Lake and river foams study reveals high PFAS levels, news.wisc.edu/lake-and-riv
er-foams-study-reveals-high-pfas-levels-even-though-underlying-water-may-be-less-contaminated
Public Health Madison & Dane County PFAS page, publichealthmdc.com/home-environment/pfas-in-dane-county
Part 1 of this series: Benefit your health by avoiding “forever chemicals” in everyday items. northsidenews.org/benefit-your-health-by-avoiding-forever-chemi
cals-in-everyday-items
