by Laina Stebbins

A state department and a long-polluting manufacturing company on Friday filed for new, strengthened cleanup standards at an Ann Arbor site that has been a source of underground contamination since the 1960s.

The chemical compound known as 1,4-dioxane has plagued northwest Ann Arbor’s water for more than 55 years, since Gelman Sciences — once a leader in the city’s industry — began polluting soil and groundwater with the carcinogen at the company’s Scio Township plant while manufacturing micro-porous filters.

The Michigan Department of Environment, Great Lakes, and Energy (EGLE) and Gelman Sciences, LLC filed a motion Friday requesting that the Washtenaw County Circuit Court enter an updated consent judgment on cleanup activities there. 

The last time the judgement was updated was in 2011, more than a decade ago. It was updated twice more before then.

1,4-dioxane, often referred to simply as dioxane, is an ether used as a solvent for a variety of uses. It is also a suspected human carcinogen that is irritating to the eyes and respiratory system, and damaging to the liver, kidneys and central nervous system.

The late Charles Gelman’s company used an estimated 850,000 pounds of 1,4-dioxane between 1966 and 1986; most was discharged to soil, surface water and groundwater at the Scio Township site. Gelman Sciences was first ordered to address the plume in 1992.

The updated consent judgement seeks to replace the 2011 judgement’s standard of 85 parts per billion (ppb) with the new, much stricter 7.2 ppb.

It also requires additional response activities from Gelman to comply with cleanup criteria for drinking water, surface water and soils, including: 

• Installing wells to monitor the 1,4-dioxane plume and track its migration 
• Investigating groundwater migrating into surface water to determine if the law requires action there
• Providing bottled drinking water to residents if a residential well exceeds 3 ppb
• Developing contingency plans to extend municipal water in certain areas if residential wells are impacted by greater than 7.2 ppb
• Investigating and proposing response activities for the property’s wetland.

“The updated terms put the cleanup on track to bring new extraction wells and monitoring wells online, bolster contingency planning, and take other necessary steps to protect public health and the environment,” said Acting EGLE Director Dan Eichinger.

Neither EGLE nor Gelman believe that a hearing is a necessary requirement for the court to approve the consent judgment, but Attorney General Dana Nessel’s department has nonetheless requested that the court hold a hearing as soon as possible, if one is necessary.