Pall plume agreement announced

Editor's Note: The MDNRE will host a March 30 public meeting in Ann Arbor to discuss the cleanup effort and answer questions about the court order discussed below.

The meeting begins at 7 p.m. at the Abbot Elementary School, 2670 Sequoia Parkway.

The Michigan Department of Natural Resources andEnvironment announced last week an agreement with a Washtenaw County company, amending cleanup requirements for a widespread plume of contaminated groundwater in Ann Arbor.

Washtenaw County Circuit Court Judge Donald Shelton ordered the change for Pall Life Sciences, successor to Gelman Sciences, amending of the plan to address groundwater contaminated with 1,4-dioxane.

The Gelman Sciences property, located on Wagner Road just south of Jackson Road in Scio Township, manufactured medical filters.

Dioxane used at the plant from 1966 to 1986 was disposed of by various methods, resulting in widespread groundwater contamination in portions of the city of Ann Arbor, Scio and Ann Arbor Townships.

The first contaminated private water supply well was discovered in 1985.

Since then, more than 120 contaminated private wells have been replaced with municipal water.

Pall Life Sciences acquired the property from its original owner in 1997 and undertook responsibility for continuing the cleanup efforts.

The court has worked with Pall Life Sciences and the MDNRE since December 2008 to identify needed modifications to its 1992 judgment, and to further address disputes that arose when the MDNRE denied a May 2009 proposal by Pall Life Sciences to modify cleanup obligations in the judgment.

The action resolves those disputes.

The amendment divides the site into two main areas - west and east of Wagner Road, and amends specific cleanup obligations for these areas.

It reflects changes made to the state cleanup law in 1995, which allowed for the initial court-ordered restrictions in 2005 on groundwater use in portions of Ann Arbor known as the Prohibition Zone.

Key components of the amendment include:

* Court-approved expansion of the Prohibition Zone to the north of the current boundary into the Evergreen Subdivision area in Ann Arbor to restrict use of the groundwater.

* Installation of additional groundwater monitoring wells by Pall Life Sciences to define and monitor the plume.

* Continued groundwater extraction by Pall Life Sciences at several locations at a reduced rate (from 1,100 to 750 gallons per minute), along with treatment and discharge to the Honey Creek tributary, with termination of extraction subject to MDNRE approval.

* Continued monitoring by Pall Life Sciences of groundwater contaminated with 1,4-dioxane that exceeds the generic residential cleanup criterion of 85 parts per billion until Pall Life Sciences can demonstrate the remaining groundwater contamination does not pose an unacceptable risk to human health, safety, welfare or the environment, now or in the future.

For more information about this site, go to the MDNRE Remediation Division Web site at , scroll to ''Sites of Interest'' under ''Contaminated Site Information'' and click on ''Gelman Sciences.'' The amendment can be found under ''Legal Documents.''

For additional site information, contact project manager Sybil Kolon at 517-780-7937 or .

Published: Thu, Mar 17, 2011