Levels of per- and polyfluoroalkyl substances (PFAS) in foam samples on the Peshtigo River spiked well above what may be safe, the DNR announced this week.
The samples were collected below the dam in Peshtigo and in a nearby roadside ditch.
Just below the dam, the PFOA level in the foam was 230 parts per trillion (ppt), and the PFOS level was about 17,000 ppt.
PFOA and PFOS are the two best-known PFAS chemicals. PFAS has been linked to health issues.
In the roadside ditch, the values were even higher.
“Those levels really are not acceptable, as far as we’re concerned,” said DNR Environmental Management Division Director Darsi Foss. “As far as people coming into contact with foam like that, we’re concerned about the impact on fish and then people eating the fish.”
Although it has recommendations for PFAS levels in groundwater, Wisconsin has no regulations or recommendations for safe levels of PFAS in surface water.
But, for comparison, Michigan’s water quality standard is 12 ppt for PFOS in streams not used for drinking water and 11 ppt for streams used for drinking water. The Peshtigo River is not a source of municipal drinking water, according to Foss.
However, testing of the water, not the foam, in the Peshtigo River would put it under Michigan’s water quality standard. Below the dam, the water tested at 2.1 ppt for PFOA and 6.2 ppt for PFOS.
“There are very low levels on the surface, but it goes over the dam, for example, in Peshtigo, it gets agitated, and those levels increase,” Foss said.
Foss said she's unaware of any states with standards for foam.
It’s unclear if the high-PFAS foam is related to Johnson Controls/Tyco (JCI). JCI has facilities in Marinette and Peshtigo for making and using fire-fighting foam. Fire-fighting foam is a known source of PFAS.
“We don’t know right now where this is coming from, but we’re going to work very diligently to work with the community and others to identify where the source of this is,” Foss said. “It may be more than one place.”
Foss said PFAS foam looks, smells, and acts differently from natural foam in water.
“The bright white foam that may smell like chemicals, that’s rather sticky, that could be from PFAS and we would urge you not to come into contact with that bright white sticky foam,” she said.
The DNR believes PFAS likes to interact with air on the water’s surface.