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Gelman 1,4-Dioxane Litigation

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On August 31, 2020, the Washtenaw County Circuit Court partially lifted the confidentiality restriction against disclosure of the negotiations between Gelman Sciences, the State of Michigan and the intervenors (City of Ann Arbor, Scio Township, Washtenaw County and its Health Department, and the Huron River Watershed Council). The proposed settlement documents that resulted from these negotiations are now public and can be viewed via a document repository webpage. The proposed documents, which still need to be voted on by the intervenors, include the Fourth Amendment to the 1992 Consent Judgment, Dismissal Order, and Settlement Agreements. Other documents and a set of videos that help with an understanding of the proposed settlement documents are also available on the repository webpage.

This Gelman 1,4-Dioxane Litigation webpage and the following frequently asked questions are intended to provide background and context, as well as additional information regarding the contents of these documents. It will explain the context of the latest negotiated settlement, illustrate the below timeline of activities over the life of both the litigation and cleanup, and answer many frequently asked questions including how community members can find more information and  how they can provide input into upcoming decisions that will be made by elected officials of the intervening parties in the litigation.

Historic Timeline Link


Frequently Asked Questions (FAQs)

1. Who is currently in charge of the cleanup?

The Michigan Department of Environment, Great Lakes, and Energy (EGLE).  

2. What is 1,4-dioxane (“dioxane") and what are the potential health impacts that might result from exposure to it?  

Dioxane is a manmade compound that mixes easily in water. It is used in industry as a solvent to manufacture other chemicals and it is a by-product in many items, including paint strippers, dyes, greases, antifreeze and aircraft deicing fluids. It also is found in other chemicals that are used to manufacture cosmetics, detergents, deodorants and shampoos.

The International Agency for Research on Cancer has determined that 1,4-dioxane is  'possibly carcinogenic' to humans because it is a known carcinogen in animals. USEPA states that it is likely to be carcinogenic to humans. More information on exposure to 1,4-dioxane and its health effects is availabe via a State of Michigan Department of Health and Human Services Fact Sheet (PDF).

3. Where is the dioxane in the groundwater and how did it get there?

Dioxane was used from the mid-1960s to the mid-1980s in the manufacturing processes at Gelman's facility on Wagner Road. Gelman's wastewater, containing dioxane, was disposed onsite during that time. In the  mid-1980s dioxane was discovered offsite, in nearby surface waters and groundwater. 

The groundwater in underground aquifers that is carrying dioxane is referred to as a plume. Multiple plumes have been spreading west in Scio Township and northeast then east into Ann Arbor, moving towards the Huron River. More information on dioxane and its location in the groundwater is located via a Washtenaw County Public Health Department Fact Sheet (PDF).  

4. When was the original Consent Judgment established and what does it now require?

 In 1992, the Washtenaw County Circuit Court entered a Consent Judgment regarding Gelman's dioxane contamination. Three amendments to the original Consent Judgment have been approved by the Court and are in effect.

The Consent Judgment and its amendments dictate the obligations of Gelman to investigate, clean up, contain and monitor the contaminated groundwater, under the direction of EGLE. 

The Court did not require full cleanup of all of the released dioxane. As one example, the  portion of the plume within the City of Ann Arbor and its projected pathway toward the Huron River, including buffer areas, is designated as the “Prohibition Zone." Because of existing and projected groundwater contamination within this zone, no uses of groundwater, such as residential wells for irrigation or other purposes, are permitted within this zone.

5. What is the Prohibition Zone (or “PZ") and how does it affect my property?

In the State vs. Gelman lawsuit, the Court approved a Prohibition Zone (“PZ") as an Institutional Control. This allows dioxane above the groundwater cleanup criterion to migrate, rather than be cleaned up, within the PZ. The “prohibition" part of the PZ title refers to a prohibition against installing or maintaining wells for drinking water or irrigation purposes on land within the PZ boundaries. All of the PZ is within the boundaries of the City of Ann Arbor, which requires all properties—regardless of where they are relative to the PZ—to connect to the city's municipal water supply system rather than get water from wells on their properties. The location of the PZ can be viewed on the map (11.19 MB).

6. What is the current status of the cleanup effort?

Gelman has been pumping and treating groundwater contaminated with dioxane it released since the early 1990's. Gelman discharges the treated water into Honey Creek which is a tributary of the Huron River. The discharge is permitted by the State of Michigan through a National Pollutant Discharge Elimination System (NPDES) permit.

7. What is the Proposed Fourth Amendment and Restatement to the Consent Judgment and what is its current status?

Following EGLE's approval of a reduction of the groundwater cleanup criterion for dioxane from 85 parts per billion (ppb) to 7.2 ppb in October 2016, a proposed fourth amendment to and restatement of the Consent Judgment has been under negotiation between Gelman, the State of Michigan (EGLE), the City of Ann Arbor, Washtenaw County and its Health Department, Scio Township, and the Huron River Watershed Council since the spring of 2017. The result of this negotiation is the proposed Fourth Amendment to and Restatement of the Consent Judgment. The proposed fourth amendment and related documents, including a chart of key changes it proposes is available via the document repository webpage.

8. What are the major elements included in the proposed Fourth Amendment and Restated Consent Judgment that are new?

The fourth amendment and restated consent judgment includes four significant elements:

  1. Additional monitoring and mapping of the contaminated groundwater
  2. Removal of additional dioxane from areas of high concentration downgradient of the source
  3. Removal/treatment of additional dioxane at the source area on the Gelman Property
  4. Expansion of the Prohibition Zone to protect public health

These elements are expected to result in an increasing of pump and treatment of groundwater by over 40 percent and an increase in removal of dioxane by over 200 percent. This will be completed by the installation of additional extraction wells as well as incorporation of two new treatment technologies for dioxane removal:

  1. Phytoremediation
  2. Heated soil vapor extraction

9. If I would like more information about the proposed Fourth Amendment and Restated Consent Judgment, where can I find it?

There is a document repository webpage with all the documents being considered by the Local Government Intervenors, including:

  • The proposed Fourth Amended and Restated Consent Judgment
  • Seven explanatory or educational videos prepared by Professor Lawrence D. Lemke  

10. How is the city capturing public feedback?

There are several opportunities for the public to provide written or oral comments, including the following:  

  • A virtual public Q&A with Washtenaw County Board of Commissioners, Ann Arbor City Council, Congresswoman Dingell and Intervenors' expert Dr. Lawrence Lemke will be held via Zoom on Thursday, Sept. 24, 2020 at 6:30 p.m. at www.washenaw.org/webcast. This joint public session will be an opportunity for elected officials to hear public input and for the public to get answers to questions regarding the Gelman Dioxane Plume Proposed Fourth Amended and Restated Consent Judgment. View Agenda Due to the complex nature of the proposed consent judgement, the public was asked to submit questions to the city via email by Sept. 18 at 5 p.m. This allowed time for meaningful answers to be provided at the Sept. 24 Q & A session.

  • EGLE conducted a separate virtual public comment session related to the proposed amendments to the consent judgment on September 14. EGLE will accept written public comments until September 21 at EGLE-RRD-Gelman@Michigan.gov.​ EGLE will publish its responses sometime after that.This FAQ will be updated with a link when that happens. Or you can sign up for updates from EGLE on its Gelman web page at https://www.michigan.gov/egle/0,9429,7-135-3311_4109_9846-71595--,00.html.

  • Written questions and comments to the city are welcome at any time by emailing gelmanquestions@a2gov.org. To the extent possible, responses to questions and comments submitted to the city will be provided to City Council and made available to the public.

  • Oral comments will be captured at the Sept. 24 joint session as well as at a future City Council Special Session, which will be scheduled in the coming weeks.

  • ​Answers to common questions received will be published on the city’s website at https://www.a2gov.org/departments/water-treatment/Pages/Gelman-1,4-Dioxane-Litigation.aspx

11. If I submitted a question to gelmanquestions@a2gov.org, will I receive a response?

  • Answers to questions provided before Sept. 18 will be provided during the Sept. 24 joint session, including a video display of relevant documentation by the intervenors’ expert Dr. Lawrence Lemke. The public can watch the Zoom meeting online www.washenaw.org/webcast or via video on demand Meetings.Agendas.Meetings. Due to the number of questions and comments being received, the significant interest in this matter, and the amount of duplication or overlap, individuals will not be sent responses.

  • Answers to common questions may be added to this webpage as available.

  • Questions and comments submitted after the Sept. 24 meeting via the city’s email gelmanquestions@a2gov.org will be provided to City Council and made available to the public.   

12. What are the next steps in advancing the cleanup effort?

The next steps in the cleanup effort are set out in, and are dependent on the fourth amendment to the Consent Judgment being approved and entered by the Court.

13. What decisions are impending, who will make them, and what is the timeline?

Prior to voting on the Fourth Amended and Restated Consent Judgment for the Gelman Sciences site in Ann Arbor and Scio Township, a virtual public Q&A with Washtenaw County Board of Commissioners, Ann Arbor City Council, Congresswoman Dingell and Intervenors' expert Dr. Lawrence Lemke will be held via Zoom on Thursday, Sept. 24, 2020 at 6:30 p.m. This joint public session will be an opportunity for elected officials to hear public input and for the people to get answers to questions regarding the Gelman Dioxane Plume Proposed Fourth Amended and Restated Consent Judgment. Scio township trustees, Ann Arbor township and Huron River Watershed Council leadership have been invited to participate. See the Document Repository webpage to review those documents.

When all three local governments and the Huron River Watershed Council have made their decisions, the parties will notify the court whether they and Gelman have approved or agreed to all these documents. The date for the vote by the Ann Arbor City Council will be posted once identified. If dates for the votes by the County Board of Commissioner or Scio Township Board of Trustees become known to the city, they also will be posted. There will be a hearing prior to each of these entities voting allowing for public comment.

The court will incorporate public comments before it decides whether to approve and enter the Fourth Amended and Restated Consent Judgment, Order of Dismissal, and Settlement Agreements. The parties have a court date on October 22, 2020, to report on the Intervenor votes, so the local government Intervenors are expecting to vote before then.

14. Could the United States Environmental Protection Agency (EPA) take over the cleanup of the site? 

EPA will typically not take over a site if it is being managed by a state agency, such as EGLE, and there is a polluter covering the clean-up costs. However, if the state governor requests that EPA take over the clean-up activities, then a three-year process would begin, during which EPA would determine whether it believes the site should be proposed for listing on the National Priorities List. Following this initial assessment, the EPA process to develop a cleanup plan for a newly listed site can take over a decade. EPA has stated that it does have emergency powers to demand immediate actions if there are actual unacceptable exposures to dioxane which EPA stated would be a threshold of 46 ppb in drinking water. In the case of the Gelman Plume, this threshold has not been exceeded so an emergency intervention would not be available for this site. Representatives of the EPA addressed these questions and more at a community meeting on January 16, 2020