The Michigan Department of Environmental Quality is holding a public meeting tonight about changes to the 1,4-dioxane groundwater cleanup plan in Ann Arbor.
The meeting will be held at 7:00 p,m. at Abbot Elementary School, 2670 Sequoia Parkway, Ann Arbor.
From the MDEQ:
The Michigan Department of Environmental Quality (DEQ) will hold a public meeting to provide information to the public regarding the Third Amendment to Consent Judgment that went into effect on March 8, 2011 regarding the Gelman Sciences, Inc. site of environmental contamination. The amendment reflects negotiations between the DEQ and Pall Life Sciences, Inc. (PLS), successor to Gelman Sciences, that began after the Department denied PLS's May 2009 Comprehensive Proposal to Modify Cleanup Program. The amendment expands the Prohibition Zone, established by the Court in 2005 to restrict the use of groundwater, into the Evergreen subdivision. The amendment also divides the site into two areas, west and east of Wagner Road, and amends the cleanup objectives for these areas.
The 1,4-dioxane groundwater plume is the result of industrial pollution from Gelman Sciences (now Pall Life Sciences). The company used the chemical in making medical filters.
The CDC's Agency for Toxic Substances and Disease Registry says few human studies have been done on the effects of 1,4-dioxane on humans, but "laboratory rats and mice that drank water containing 1,4-dioxane during most of their lives developed liver cancer; the rats also developed cancer inside the nose." The ATSDR says, "scientists are debating the degree to which the findings in rats and mice apply to exposure situations commonly encountered by people."
Here's some background from MDEQ on how the contamination started:
Groundwater in parts of Washtenaw County, including areas in the City of Ann Arbor and Ann Arbor and Scio Townships, is contaminated with the industrial solvent 1,4-dioxane…
Gelman Sciences, now Pall Life Sciences (PLS), used 1,4-dioxane in their manufacturing process.
Between 1966 and 1986, wastewater containing 1,4-dioxane was sprayed on its lawns and stored in unlined lagoons. The chemical seeped through soil and rock layers into the groundwater and began to spread; 1,4-dioxane is now found in a deep ground-water aquifer called Unit E.
Its physical properties allow 1,4-dioxane to spread rapidly in groundwater.
The Washtenaw County Circuit Court issued an order to protect the public from exposure to contaminated groundwater in some parts of Ann Arbor and the surrounding area. The order "prevents use of groundwater that is or may become contaminated with unacceptable levels of 1,4-dioxane."
The area with these restrictions is called the "Prohibition Zone". You can see a map of the Prohibition Zone here.