(FOX 2) - A medical filter manufacturer responsible for a toxic groundwater plume threatening Ann Arbor's water supply has reached an agreement to clean the contaminated soil and water, the EPA says.
Gelman Sciences LLC and the federal government reached a legal agreement to address the environmental hazard, which includes a long-term plan to remove and rehabilitate the soil and groundwater found within a three-by-one mile plume.
The site was added to a Superfund site list by the EPA in 2026.
Ann Arbors toxic plume
The backstory:
Gelman Sciences manufactured medical filters from 1963 to1986. During the operations, the manufacturer discharged wastewater that contained a forever chemical known as 1,4-dioxane.
Released into surrounding ponds, the man-made chemical has a faint odor and does not break down in the environment. It was used primarily as an industrial solvent and frequently a part of paper, cotton, and textile products.
However, it also a suspected carcinogen and chronic exposure can damage one's livers and kidneys.
The toxic plume containing the chemical has been found in private wells as it migrated into the groundwater under homes in Ann Arbor and Scio Township.
The groundwater plume threatening groundwater in Ann Arbor and Scio Township. Credit: Washtenaw County.
Zoom out:
As a result of the contaminated water, residents have been forced to abandon their private wells for municipal water lines.
The contamination at one point forced the city to close one of its water wells due to the presence of 1,4-dioxane.
After being nominated to the National Priorities List in 2021, which lists Superfund sites, it was officially added in March 2026.
What Gelman Sciences will do
What's next:
As part of its administrative settlement agreement with the EPA, Gelman Sciences is required to carry out the following:
- Conduct a remedial investigation and feasibility study to determine the extent of the contamination and evaluate potential solutions.
- Excavate soils contaminated with 1,4-dioxane from the former burn pit area on Gelman’s property.
- Increase the groundwater extraction and treatment rates in the eastern groundwater plume to reduce the spread of groundwater contamination.
- Install additional groundwater monitoring wells to further define the easternmost extent of 1,4-dioxane groundwater contamination.
- Provide grant funding for community groups to hire an independent technical advisor to help interpret and explain technical reports, site conditions, and EPA’s proposed actions.
What they're saying:
"Since adding the Gelman Sciences site to the National Priorities List in March, EPA has moved quickly to put strong oversight and clear expectations in place," said EPA Region 5 Administrator Anne Vogel. "This order provides a focused path for accelerating critical work to protect residents and advance long-term aquifer restoration, demonstrating EPA’s commitment to delivering effective and timely Superfund cleanups."
The Source: THe EPA and previous reporting were cited for this story.