Michigan Utilities Have Dioxane Plume On Their Radar

A dioxane plume has become an issue for water providers and public health officials in Michigan.

There is a growing concern that dioxane contamination making its way through residential wells could eventually reach a main public water source, the Huron River. A dioxane plume that “is slowly working its way toward the Huron River in Ann Arbor has already reached some private wells on the west side of the city,” Michigan Radio recently reported.

“In response to heightened concerns about the Gelman dioxane plume spreading through the area's groundwater, Washtenaw County Public Health is working to supply residents with more information,” Michigan Live reported.

Dioxane is a synthetic industrial chemical and known carcinogen. The Michigan plume has been working its way through local groundwater for years. Now officials are worried that it could reach a major public water source.

“Since the company responsible for the cleanup, Pall Life Sciences, have done little to slow the spread, city officials think the Environmental Protection Agency needs to step in to take care of the cleanup,” Michigan Radio reported.

The problem dates back to the ‘60s. “Pall purchased Gelman Sciences, the medical supply company that contaminated the area, after it disposed of the solvent 1,4 dioxane by spraying it on nearby fields and using a deep water injection well from the 1960s through the 1980s,” the report said.

Michigan officials are looking for regulatory measures to address the problem. The Department of Environmental Quality proposed to lower the state’s standard for 1,4 dioxane. “The current state standard is 85 parts per billion, while the rest of the world is near three parts per billion. The new proposed Michigan standard is 7.5 parts per billion,” Michigan Radio reported.

How is 1,4 dioxane treated? Here are a few methods described by the U.S. EPA:

• Pump-and-treat remediation can treat dissolved 1,4-dioxane in groundwater and control groundwater plume migration, but requires ex situ treatment tailored for the unique properties of 1,4-dioxane (such as, a low octanol-water partition coefficient that makes 1,4-dioxane hydrophilic).
• Commercially available advanced oxidation processes using hydrogen peroxide with ultraviolet light or ozone is used to treat 1,4-dioxane in wastewater.
• Ex situ bioremediation using a fixed-film, moving bed biological treatment system is also used to treat 1,4-dioxane in groundwater.
• Microbial degradation in engineered bioreactors has been documented under enhanced conditions or where selected strains of bacteria capable of degrading 1,4-dioxane are cultured, but the impact of the presence of chlorinated solvent cocontaminants on biodegradation of 1,4-dioxane needs to be further investigated.
• Photocatalysis has been shown to remove 1,4-dioxane in aqueous solutions. Laboratory studies documented that the surface plasmon resonance of gold nanoparticles on titanium dioxide (Au – TiO2) promotes the photocatalytic degradation of 1,4-dioxane.

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