Dioxane found in shallow groundwater in Ann Arbor park

Associated Press

Ann Arbor — The toxic chemical 1,4-dioxane has been detected in shallow groundwater in Ann Arbor.

MLive reports the discovery of the chemical beneath Waterworks Park is the latest revelation following new investigations into the plume spreading from the former Gelman Sciences property.

Michigan Department of Environmental Quality officials say the concentrations are about 2-3 parts per billion, below the department’s precautionary screening levels for risk of vapor intrusion into buildings. Officials say there isn’t an immediate public health risk.

But some citizens worry that the discovery of the chemical not far below the surface in a relatively dense neighborhood has the potential for human exposure.

The department has proposed a new vapor-intrusion screening level of 29 parts per billion for when dioxane-contaminated groundwater is in contact with a building foundation.