For more than three decades, the spread of 1,4-dioxane contamination—commonly known as the “Gelman Plume”—has remained one of the most persistent environmental concerns in the Ann Arbor area. What began as an industrial pollution issue with Gelman Sciences has evolved into a long-running public health and environmental debate—one shaped as much by scientific uncertainty as by community persistence.
Now, with the site’s new designation under the federal Superfund program, many residents are asking what this shift will mean for cleanup, transparency, and long-term safety.
Roger Rayle, chair of the Coalition for Action on Remediation of Dioxane (CARD) and Scio Residents for Safe Water (SRSW), has been deeply involved in tracking and advocating around the plume for over 30 years. His reaction to the recent Superfund designation was succinct: “All good news.”
A “fundamental shift” in cleanup
The plume originates from groundwater contamination linked to the former Gelman Sciences site, where 1,4-dioxane—a likely human carcinogen—entered the aquifer and began migrating beneath western Washtenaw County. Over time, the contamination spread far beyond its original source, raising concerns about its reach toward residential neighborhoods and municipal water systems…