Drainage ditch near Tyco again shows elevated levels of PFAS
Elevated levels of “forever chemicals” were once again found at a Marinette-based plant known for mixing firefighting foams.
Tyco Fire Products, a subsidiary of Johnson Controls, announced Friday that the levels of PFAS found in a drainage ditch near its property showed levels of PFAS roughly 50 times higher than the recommended threshold for groundwater. According to a press release from the Wisconsin Department of Natural Resources, Ditch B showed concentrations of 1,000 parts per trillion of PFOA and 73 parts per trillion of PFOS, in addition to other PFAS compounds. The state’s recommended limit is about 20 parts per trillion, the release said.
PFAS, or per- and polyfluoroalkyl substances, are a group 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 chemicals are persistent, remaining both in the environment and human body over time. Accumulation of the chemicals in the body can cause cancer, studies have shown, or other adverse health effects.
The chemicals have been a legacy problem in Marinette at the Tyco facility, where fire-fighting foam is mixed.
The company starting mixing and testing the compounds outdoors in 1962, but was halted in 2017 when environmental pollution came to light.
According to a release from Tyco, the company has been regularly monitoring Ditch B, which measured below the limit until recently. The company attributed the issue to an unusually rainy summer, which has made the water levels higher in bodies of water in Marinette, including the ditch.
The Ditch B system, the release said, can handle up to 450 gallons per minute typically, with a surge rate of 600 gallons per minute, the release said. This summer, the flow rate of the ditch has been about 1,700 gallons per minute, putting unusual stress on the filtration system and allowing some water to get around it.
The company will install a new pump system, the release said, as well as addressing sediment accumulating in the ditch from the high water levels.
“The current situation at Ditch B is not up to our standards as an environmental leader and we will do everything we can to resolve it quickly,” the release said.
The company also submitted test results to the DNR for Ditch A, which is on the company’s property and for the mouth of Green Bay. Both results were below 20 parts per trillion, according to Tyco’s release.