Photo: Kids fishing from Starkweather Creek at the Olbrich boat launch in summer 2018 (Maria Powell)
By Abigail Becker, Cap Times
Wisconsin’s Department of Natural Resources confirmed Thursday high concentrations of contaminants known as PFAS in a sample of foam collected at Starkweather Creek near the Olbrich Park boat launch at the end of October.
In a statement Thursday, Madison Mayor Satya Rhodes-Conway called the high concentrations of contaminants “concerning.”
“I’ve asked the City Parks Division to increase monitoring of the boat launch and to report any cases of foam they identify to the DNR,” Rhodes-Conway said. “City staff are also working with the county and the state on a coordinated response to PFAS pollution in Starkweather Creek.”
PFAS, per- and polyfluoroalkyl substances, are a class of man-made chemicals whose whose indestructible molecular carbon-flourine bonds allow them to exist in the environment for decades and possibly centuries.
They’re found in products microwave popcorn bags and disposable plates. These “forever chemicals” are also found in firefighting foam and contributed to elevated PFAS levels at an outlet into Lake Monona under Blount Street after a transformer fire at Madison Gas and Electric over the summer.
As of Dec. 13, the Madison Fire Department started using a brand of firefighting foam shown to be PFA-free, according to manufacturer claims and an independent test of the product.
The DNR found that the sample of foam taken Oct. 25 from Starkweather Creek near Olbrich Boat Launch showed 460 to 610 parts per trillion of PFOA and 80,000 to 92,000 parts per trillion of PFOS. PFOA, perfluorooctanoic acid, and PFOS, perfluorooctanesulfonic acid, are types of PFAS.
Samples taken of water at the surface showed 9.5 to 10 parts per trillion of PFOA and 400 parts per trillion of PFOS.
PFAS in waterways tend to accumulate where air and water meet and concentrate in foam, which lead to higher levels in foam than in the surrounding wtaer, according to the city.
Other PFAS contaminants were also detected in the foam and water samples and can be found in the DNR’s report.
Given the high levels of PFAS in the foam, the DNR and state Department of Health Services recommends people avoid making any contact with the foam. Swallowing foam with PFAS could have adverse health effects, according to health officials.
The Environmental Protection Agency warns against consuming water with more than 70 parts per trillion of PFOA and PFOS. The state’s Department of Health has proposed a safe drinking water standards of 20 ppt for the two.
If people or pets come into contact with foam from the waterway, they should rinse off with fresh water. Signs installed by the city warn residents of the elevated contaminant levels.
City staff are coordinating with Public Health Madison and Dane County to hold a public information meeting in January 2020 about PFAS in Starkweather Creek. A date and location will be announced when finalized.
