State officials are recommending people watch their intake of certain species of fish from Lake Monona and Starkweather Creek based on new data showing high contamination levels.
Recent sampling by the Wisconsin Department of Natural Resources (DNR) shows elevated PFOS in fish tissue and surface water in those waterways. PFOS is one of many per and polyfluoroalkyl substances (PFAS).
PFAS are a group of human-made chemicals used for decades in numerous products, including nonstick cookware, fast food wrappers, stain-resistant sprays and certain types of firefighting foam. These legacy contaminants have made their way into the environment in a variety of ways, including spills of PFAS-containing materials, discharges of PFAS-containing wastewater to treatment plants and certain types of firefighting foams.
The Federal Aviation Administration requires airport firefighting services to use aqueous film-forming foam (AFFF) in emergencies because of its superior ability to extinguish fires started by jet fuel, gasoline, and other petroleum based chemicals.
Dane County Regional Airport is one of the first airports in the nation to research and implement appropriate mitigation measures for PFAS and will continue working with the DNR, the Wisconsin Air National Guard, and other partners to develop a detailed action plan.
“We are committed to working with local, regional, and national partners to address this issue,” airport director Kim Jones said. “Our most important resource is the health and safety of our residents, and it is essential that all agencies work together to create the best solution for Dane County residents as we once again lead the nation and develop a case study for airport PFAS mitigation nationwide.”
The plan will include rigorous testing, methodical and scientific research, as well as collaboration with local and national experts to ensure an appropriate and sustainable methodology, Jones said. The plan will need to be adaptable as ongoing research of PFAS continues worldwide.
“This is a national problem involving a wide array of industries and commercial applications, as well as many state and federal agencies,” Jones said. “We are investigating appropriate cleanup actions based on risk as well as developing solutions that will be a benchmark for other airports.”
As part of the DNR’s PFAS efforts to monitor fish tissue and water chemistry at select sites around the state, surface water samples were collected at four locations in the east and west branches of Starkweather Creek over the summer of 2019, along with fish near the mouth of the creek where it enters Lake Monona. PFAS was detected in samples from all four locations.
In October, additional surface water sampling was conducted at the four original sampling locations as well as 11 new locations in Starkweather Creek and five locations in Lake Monona.
PFOS was detected in all fish sampled from Lake Monona and Starkweather Creek.
The Department of Health Services (DHS) recommends eating carp, largemouth bass, northern pike, walleye and perch from Lake Monona no more than once a month, and bluegill no more than once a week.
At Startweather Creek, DHS recommends eating carp, largemouth bass, walleye and perch no more than once a month, and bluegill no more than once a week.
PFAS contamination was found in Starkweather Creek from its headwaters northeast and east of the Dane County Regional Airport, through its length to where it discharges into Lake Monona.
PFOS concentrations were lowest northeast and east of the airport and in the East Branch of Starkweather Creek. The highest concentration was found in a stream on the southeast side of the airport.
PFAS concentrations were generally stable in the creek from Anderson Road until the West Branch mixes with the lower PFAS concentrations in the East Branch south of Milwaukee Street. That mixing appears to lower the PFAS concentrations in the creek until it enters Lake Monona.
Concentrations in Lake Monona were less than the concentrations found in Starkweather Creek between Anderson Road and Lake Monona.
Starkweather Creek and Lake Monona are not sources of water for the Madison Water Utility. The DNR is currently working with DHS on developing groundwater, drinking water and surface water standards for PFAS.
Public Health of Madison and Dane County officials said PFAS chemicals do not easily absorb into the skin. It is safe to bathe, as well as do laundry and household cleaning. It is also safe to swim in and use water recreationally. Getting water with PFAS on your skin will not harm you, but it is advised to wash your hands, or rinse your pets after being in water containing PFAS so that water is not accidentally ingested.
Public information meetings will be scheduled soon to update Dane County residents on plans to address PFAS.
For questions about the health effects of PFAS, visit the Public Health of Madison and Dane County website at www.publichealthmdc.com.