In 2017, the Huron River Watershed Council joined the case between Gelman Sciences and the State of Michigan to renegotiate the cleanup of the 1,4-dioxane plume in groundwater beneath western Ann Arbor and Scio Township. HRWC joined as an intervenor along with the City of Ann Arbor, Scio Township, and Washtenaw County. A Consent Judgment will dictate the conditions of enforcement for managing the contaminated groundwater.

This week, the renegotiated proposed Consent Judgement (CJ) has been made available to the public. You can see the legal documents, a summary of changes between the existing and renegotiated proposed Consent Judgement, and some videos explaining the technical details of the contamination and clean up here. Other useful links include the HRWC webpage on 1,4-dioxane and the City of Ann Arbor’s webpage on the ligation.

The new proposed CJ (4th Amended) substantially improves protections for residents living near or above the dioxane plume compared to the outdated CJ currently in effect (3rd Amended). It will also provide greater protections for the Huron River and its tributaries. Three key improvements are:

  1. The proposed Consent Judgement is more protective of human health and the environment by setting stricter clean up criteria. A more stringent limit of 7.2 parts per billion will be in effect instead of the old and weak limit of 85 parts per billion.
  2. More monitoring wells will be installed in key areas. Regarding HRWC’s unique interest in this case, new monitoring locations on the east side of the plume will provide an earlier warning if the plume expands toward the river.
  3. More treatment, using updated methods that are safer for the environment, will be required.

Most importantly, the proposed CJ sets a far more protective clean up criteria for 1,4-dioxane that Gelman will now be required to adhere to. Any future legal action involving federal or state agencies to address the contamination will have a much stronger foundation because it will be based on that lower limit.

Negotiations did result in an expansion to the Prohibition Zone. This will affect residents included within the expanded boundary by prohibiting the consumptive use of groundwater in a larger area. However, it will provide additional protection for residents nearest to the expanding plume that would be most at risk of future contamination in their wells and a process for reevaluating the boundary to determine if over time the area can be reduced.

This Consent Judgement is a significant improvement from the last, but risks, uncertainties, and limitations remain. The Gelman plume has been growing since the 1960s and it will continue to negatively impact our communities for decades. This is in part due to limitations of state regulations. It is also extremely difficult to clean up groundwater contamination of this magnitude once the damage has been done. It is a painful reminder that pollution must be kept out of the environment to begin with.

There will be several ways for the public to provide comment on the proposed Consent Judgement.  Currently scheduled, EGLE will be hosting a public meeting on the proposed amended Consent Judgment on September 14th, 2020. HRWC will update our webpage with additional opportunities as they are scheduled.