by Laura Schulte – Milwaukee Journal Sentinel

MADISON – A program aimed at destroying “forever chemicals” in the soil at the Dane County airport is showing promising results after its first nine months. 

Since deploying microbes to breakdown PFAS in the soil at the Dane County Regional Airport, there has been a 97% reduction in the amount of the toxic compounds month over month in a well installed to measure the compounds in nearby groundwater. 

“We’re encouraged by the early results of the program and looking forward to expanding it and continuing our dedication to this effort,” airport director Kim Jones said in a release. “Airports across the United States are all seeking solutions to combat this issue, and DCRA is proud to be on the leading edge of this innovative and promising technology.”

The results could indicate a way forward for other contaminated sites in Wisconsin and across the world looking for solution to remove PFAS at their source. 

“This test is just the start of what could possibly be a widespread solution to remediating PFOA and PFOS at sites nationwide. We are very optimistic about these initial results, and look forward to what future tests prove to accomplish,” Maj. Gen. Paul Knapp, adjutant general of Wisconsin and head of the Wisconsin National Guard, said in a release. 

The Dane County airport is one of only a handful of sites in the world testing new technology that utilizes naturally occurring microbes from the soil to consume PFAS, breaking down the bonds in the compounds until all that remains are non-harmful substances. 

The airport and the 115th Fighter Wing of the Air National Guard, which operates Truax Field in the same area, are working with Fixed Earth, a Canadian-based company that specializes in the utilization of microbes to address contamination, as well as the Verona-based ORIN Technologies. 

How are microbes being used to eat PFAS?

The microbes were harvested from the ground at the airport and bred in a lab. The idea came from a similar technique used on oil spills, in which microbes are also used to consume the contaminants in the environment. 

The microbes are injected into the ground in areas where PFAS have been concentrated through the use of charcoal, allowing them to eat through the compounds and break them down into non-harmful waste. 

The PFAS at the airport have become an increasingly large issue for the area since their discovery in 2019. 

The contamination is likely linked to the use of PFAS-containing firefighting foam, which has been recommended for use by the Federal Aviation Administration for years. As a part of yearly requirements, the airport and the Air National Guard were required to test the foam, discharging it on the ground and washing it away. 

The foam is recommended for use at airports because it is so successful in putting out hot fires — like those that occur when there is gasoline or jet fuel involved. 

Over time, the PFAS from the foam migrated through the soil and into the water in the area, including Starkweather Creek, which now faces one of the worst contaminations in the city. The chemicals have also worked themselves into many of the other water bodies in Madison, including Lakes Monona, Waubesa and Kegonsa, as well as a portion of the Yahara River. 

What are PFAS and how are they used?

PFAS, or per- and polyfluoroalkyl substances, are a family of man-made chemicals used for their water- and stain-resistant qualities in products like clothing and carpet, nonstick cookware, packaging and firefighting foam. The family includes 5,000 compounds, which are persistent, remaining both in the environment and human body over time.  

The chemicals have been linked to types of kidney and testicular cancers, lower birth weights, harm to immune and reproductive systems, altered hormone regulation and altered thyroid hormones. The chemicals enter the human body largely through drinking water. 

Laura Schulte can be reached at and on Twitter at @SchulteLaura