As a plume of contaminated ground water keeps expanding in Ann Arbor, the city council wants the state to move faster to protect people from harmful exposure.
To be clear: Ann Arbor drinking water is safe.
But growing swaths of the city’s ground water is no longer a good idea to ingest (and again, the city is NOT getting their water from those areas,) thanks to chemical runoff from years ago.
That chemical compound is 1,4 dioxane and it seeped into ground water between the 1960's and 1980's when a manufacturer stored it in unlined lagoons.
That manufacturer is Gelman Science, now called Pall Life Sciences. They used the chemical to make medical filters, though they no longer have a business operation in Ann Arbor.
During that period, some of that leakage (for example, when Gelman-Pall was spraying the water that had the chemical directly onto the ground) was approved by the DNR.
In part, that’s because the science around 1,4 dioxane is evolving.
Scientists have known it causes cancer in animals since the 1960's.
And right now, the Michigan Department of Environmental Quality draws the safety line for 1,4 dioxane at 85 parts per billion.
That’s the amount of dioxane in drinking water the EPA thought would, over a lifetime of exposure, raise your risk of cancer.
Yet more recently, EPA studies suggest 1,4 dioxane is more dangerous than previously thought.
The most recent science suggests being exposed over your lifetime to water that has just 3 parts per billion 1,4 dioxane can increase your risk of cancer.
At that level, the EPA studies suggest 1 in 100,000 people will be diagnosed with cancer.
Meanwhile, the state’s cleanup standards still don’t mandate cleaning up 1,4 dioxane until water pollution reaches that 85 parts per billion mark.
Currently, the MDEQ is looking at updating their standards.
But it’s taking a long time.
Too long, according to the resolution passed by the Ann Arbor city council this week:
“The MDEQ missed its self-imposed deadline of December 2012 to set new standards for cleanup criteria…which were to be passed on the EPA…review.”
Now, the MDEQ’s new deadline is the end of this year.
Sue Erickson is with the MDEQ, and she’s says they’re “cautiously optimistic” that they can make that deadline this time.
But she stresses that revising these standards isn’t simple.
Erickson says the MDEQ can’t just update standards for one chemical: instead, they release new standards for 309 separate chemicals all at once.
And getting a compromise out of environmentalists and the regulated businesses is no cake walk.
"We are looking at this as a holistic process. And I wouldn't say that they are dragging their feet. What we are trying to do is get consensus."
But for Ann Arbor city councilwoman Sabra Briere, delays could be dangerous.
“One of the big concerns is that the [contaminated] plume will travel…and will enter the drinking water,” she says.
“Another concern is it will bypass the open water and end up in well water downstream. These are things nobody can accurately predict,” Briere says.
“And that creates a tension. And the tension can be mitigated by increasing the cleanup standard, and not having 85 parts per billion [allowed in the water], which is [a standard] they’ve been clinging to for the last 10 years.”
You can see a map of where the plume currently is, and a timeline of how the contamination entered Ann Arbor water here.