May 11, 2020

Milwaukee Estuary Area of Concern Sees PFAS in Surface Water

The Wisconsin Department of Natural Resources found the presence of per- and polyfluoroalkyl substances (PFAS) in surface water and sediment sampling


pfas contamination

The Wisconsin Department of Natural Resources (DNR) has received results from surface water and sediment sampling conducted in November 2019. 

The results indicate the presence of per- and polyfluoroalkyl substances (PFAS) in areas targeted for dredging across the Milwaukee Estuary Area of Concern (AOC).

There is a presence of PFAS compounds in sediment and all surface water samples taken in the Milwaukee Estuary AOC, reported the Milwaukee Courier. Perfluorobutanoate (PFBA) was found in 100% of the surface water samples as well. 

In total, fourteen locations were sampled for 35 PFAS compounds. The locations are in the Milwaukee, Menomonee, Kinnickinnic Rivers and inner and outer harbors, as well as one location in Lake Michigan. 

The highest concentrations of PFAS were found in the samples taken furthest upstream from Lake Michigan, reported the Milwaukee Courier. Among the 14 locations sampled, PFAS concentrations in sediment and surface water are highest in the Kinnickinnic River with Perfluorohexanesulfonate (PFHxS) at 44.4 parts per trillion (ppt) in surface water and Perfluorooctanesulfonic acid (PFOS) at 9.1 parts per billion (ppb) in sediment.

"The WDNR Office of Great Waters (OGW) is responsible for implementing Wisconsin’s AOC Program, which is a nonregulatory program aimed at restoring Beneficial Use Impairments (BUIs) in AOCs," said the Removal Target Updates for the Milwaukee AOC document, written by WDNR Office of the Great Waters. "This program is intended to address legacy issues, such as problems caused by historical contamination, and does not replace or supplant existing regulatory programs. Removal targets are a key element of the AOC program. They define the end goal that determines when BUIs can be considered adequately addressed for the AOC program, and thus eligible to be removed."

Location 14, which is closest to the drinking water source intake for the Linnwood and Howard Avenue Water Treatment Plants, show concentrations of PFOA and PFOS at less than detection limits of 1 part per trillion (ppt) each, reported the Milwaukee Courier.

The results will assist the future management of river sediment dredged during the clean-up of the AOC, since some of the river sediment in the AOC is contaminated.

The Department is currently awaiting PFAS results from fish that were collected from the Milwaukee River and additional fish will be collected from the AOC in 2020. DNR’s fish consumption guidance restricts consumption in the Milwaukee Estuary based on Polychlorinated biphenyls (PCBs). 

DHS recommends people avoid drinking or swallowing water and to shower after coming into contact with the water, to prevent accidental ingestion. Pets should be thoroughly rinsed off after contact with water as well, adds the DHS.

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