You are here: Home Government Departments Environmental Health 1,4-Dioxane Coalition

CARD: Coalition for Action on Remediation of Dioxane

Welcome To The CARD Site

The Coalition for Action on Remediation of Dioxane (CARD) is a partnership of local governments and citizens that develops policies and strategies to address the groundwater contamination from the industrial solvent 1,4-dioxane, released by Gelman Sciences, now Pall Life Sciences (PLS).  The groundwater contamination has expanded in Washtenaw County to an area over three miles long and one mile wide.  The remediation of this site is likely to take an additional 20 years or more based on Pall Corporation and the Michigan Department of Environmental Quality (MDEQ) estimates.

CARD's activities include actions related to permits, well installations, remediation technologies, treatment system effluent discharges, contamination migration, pipeline installation and maintenance, and other appropriate measures.

1.4-Dioxane Plume

1,4-Dioxane Plumes and Associated Well Locations Map, Updated May 2015.  (Click on map to enlarge image)


CARD Meeting Calendar:


Meetings are held at the Washtenaw County Western Service Center, 705 N. Zeeb Rd., Ann Arbor, MI 

Click here for directions to Washtenaw County Western Service Center


Click Here to read the Final Report!



Michigan's Department of Environmental Quality Reaches Settlement with Pall Corporation 

On July 1, 2014, a settlement was filed in Washtenaw County Circuit Court between the Michigan Department of Environmental Quality (DEQ) and Pall Corporation.  Pall Corporation is to pay $500,000 to cover past monitoring costs and clean-up oversight to the DEQ.  For more information, read the full Settlement Agreement by clicking here or read the article here.


The dispute resolution (Petition for Dispute Resolution) hearing on the Western Area Monitoring Plan 

was heard on Wednesday, January 11, at 1:30 PM, at 101 E. Huron Street, second floor, Ann Arbor, in the court room of the Honorable Donald E. Shelton.

Honorable Judge Shelton ruled for Gelman Sciences d/b/a PALL Life Sciences, Inc.'s (Defendant) at the hearing "without prejudice" .  The ruling allows for the DEQ to still rejoin the issue with better supporting documentation.  The outcome of the ruling is that Gelman/Pall Life Sciences will not be required to install additional compliance monitoring wells, as requested by the MDEQ. The proposed additional compliance monitoring wells were to be installed at proper depths and closer to the known plume(s) at the core area, to aid in determining if the Consent Judgement requirement of non-expansion is achieved.

Also available for review is the Plaintiff's Brief in Response to Defendant's Petition for Dispute Resolution.


Below is the text of of the Press Release by the DNRE regarding Amendments to the Consent Judgment governing the cleanup of the PALL/Gelman site of 1,4-dioxane contamination.


FOR IMMEDIATE RELEASE                                            Contact:        Brad Wurfe

March 9, 2011                                                                                            517-373-7917


Court revises cleanup plan for Ann Arbor site


The Michigan Department of Natural Resources and Environment today announced 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. Today’s action resolves those disputes.

The amendment divides the site into two main areas – west and east of Wagner Road (see map - link provided below as Attachment E) 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.

The MDNRE will host a March 30 public meeting in Ann Arbor to discuss the cleanup effort and answer questions about the court order. The meeting begins at 7 p.m. at the Abbot Elementary School, 2670 Sequoia Parkway.

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


Below are links to the specific document related to the Third Amendment to Consent Judgment signed by Judge Donald Shelton, Washtenaw County Circuit Court.

Stipulated Order Amending Previous Remediation Orders
Third Amendment to Consent Judgment (final, without signatures)
Attachment A

Attachment B [B-1 and B-2]

Attachment C

Attachment D (not part of 3rd Amendment)

Attachment E

Attachment F

Attachment G

Attachment H

Attachment I


US EPA IRIS Report on 1,4-dioxane Human Health Assessment

The Environmental Protection Agency (EPA) August 11, 2010, published the Integrated Risk Information System assessment for 1,4 dioxane. This assessemt developed a revised cancer slope factor, which is used in the calculation of various cleanup and drinking water related criteria.


Carcinogenicity Assessment for Lifetime Exposure

Weight-of-Evidence Characterization:

  • Likely to be carcinogenic to humans

Weight-of-Evidence Narrative:

  • In accordance with the Guidelines for Carcinogen Risk Assessment (U.S. EPA, 2005, 1,4-dioxane is characterized as "likely to be carcinogenic to humans."
  • This may be a synopsis of the full weight-of-evidence narrative. See IRIS Summary.


Quantitative Estimate of Carcinogenic Risk from Oral Exposure


Risk Level Lower Bound on
Concentration Estimate*

E-4 (1 in 10,000)

35 μg/L

E-5 (1 in 100,000)

3.5 μg/L

E-6 (1 in 1,000,000)

0.35 μg/L

*The unit risk and concentration estimates assume water consumption of 2 L/day by a 70 kg human.


Quantitative Estimate of Carcinogenic Risk from Inhalation Exposure

  • Information reviewed but value not estimated. See IRIS Summary.


1,4-Dioxane included on Final EPA Contaminant Candidate List 3

The EPA has finalized the list of chemicals to be included in the Contaminant Candidate List 3 (CCL 3), which identifies contaminants that are currently not subject to any proposed or promulgated national primary drinking water regulations, that are known or anticipated to occur in public water systems, and which may require regulation under the Safe Drinking Water Act (SDWA).  The list includes, among others, pesticides, disinfection byproducts, chemicals used in commerce, waterborne pathogens, pharmaceuticals, and biological toxins. The EPA uses a multi-step process to select 116 candidates for the final CCL 3. The final CCL 3 includes 104 chemicals or chemical groups and 12 microbiological contaminants.

Fact Sheet: Final Third Drinking Water Contaminant Candidate List (CCL 3)


(old) MDEQ Denies Pall/Gelman's (PLS's) Proposal

On 6-15-2009, MDEQ denied Pall/Gelman's (PLS's) 5-4-2009 proposal to reduce its dioxane groundwater cleanup activities and risk polluting more area water supplies... including Barton Pond where Ann Arbor gets 80% of its water.

[DEQ 6-15-2009 Response ] [DEQ Public Comment Response ]

Stay turned to make sure this decision is not overturned as it makes its way through upcoming court hearings.

The MDEQ Powerpoint from the May 27, 2009 Public Meeting is availabe for review.


Past Events:

On May 4, 2009, PALL submitted the "Comprehensive Proposal to Modify Cleanup Program" at the former Gelman site, now owned by PALL. The text of the document is attached, see below. Here is a link to the complete document including maps and tables.

Pall Corporation (PALL) and the Michigan Department of Environmental Quality are required to adhere to the schdule contained in the April 22, 2009, Stipulated Order which modified the previous April 6, 2009, Order.

While the Washtenaw County Circuit Court (Court) is not supporting the public comment period that MDEQ requested, the MDEQ is making one available, albeit much shorter (4 weeks).

A main concern is that PLS is interested in expanding the prohibition zone to include the Evergreen area, eliminating the Consent Order requirement to clean up to 85 there and instead allowing up to 2800 ppb of 1,4-dioxane to migrate further downgradient.

Currently, there is very little geologic or hydrogeologic information to the north of the "evergreen plume" (Dexter-Ann Arbor Rd. area west of Maple Rd. and east of M-14) and no demonstration that expanding the prohibition zone toward Barton Pond will have no detrimental effects at Barton. Ann Arbors drinking water comes from a combination of sources. Eighty-five percent is drawn from the Huron River in Barton Pond. The remainder comes from groundwater wells located on the south side of town.

The concern of those close to the issue is that the Court took the Groundwater Surface Water Interface standard (2800ppb) and "dragged" it back from the Huron River to Maple Road with very little information demonstrating that the plume would head only to the east. It is unclear whether the Court is willing (or MDEQ will be effective in arguing) to "drag" the 34 ppb standard for a drinking water source back to the northern boundary of the prohibition zone.

Key issues related to the the revised "global" remediation strategy are the current lack of demonstration that there is no northerly flow (toward Barton Pond) prior to allowing this and what is the contingency plan if/when something goes wrong. The current proposal by PALL does not include a contingency plan.


Subscribe to CARD News and Updates

Links to 1,4-Dioxane Related Information


We welcome your feedback and suggestions! For more information contact Jennifer Conn at 734-222-3855 or by email.

Document Actions
Google Translate