Well to stay closed until winter

Well to stay closed until winter

■ Health officials say dioxane not found in nearby residential wells.

By SUSAN L. OPPAT

NEWS STAFF REPORTER

A municipal well that was shut down in March because of chemical contamination will remain out of operation at least until winter, but health officials say additional testing shows nearby residential wells are not contaminated.

Janice Skadsen, water quality manager for the city of Ann Arbor, said the shutdown of the Montgomery well at Montgomery and Bemidji streets on the west side will not cause any water shortages during high-demand summer months. The well is normally used only during the winter, when the water treatment plant needs warmer water than what is then available in the Huron River.

The well was shut down after water quality testing revealed the presence of 1,4 dioxane, a manmade chemical. The water tested at 2 parts per billion (ppb), well below the state-recommended 85 ppb safely level, but Skadsen said they chose to err on the side of caution. There is no federal safety standard, but dioxane is believed to be a potential carcinogen.

State officials recommended testing two private, residential wells near Montgomery, but neither was contaminated and both remain open.

While dioxane is the substance that polluted an area around the Pall Sciences plant in Scio Township, the chemical has never entered the Huron River or area drinking water, even before treatment, Skadsen said.

Sybil Kolon, environmental quality analyst with the state Department of Environmental Quality, said the source of the recent contamination has not been determined. 

But Skadsen said the city applied last week for a state grant to pay for a wellhead protection program and testing that should, within the next year, map the source of water that feeds into the Montgomery well, then study local land uses and potential contamination sources.

After that, she said, the city can decide where to sink new wells and teach local residents how to avoid contaminating the water.

Skadsen said the city is still evaluating whether it can operate the treatment plant efficiently next winter without the well. They’ll run the well for up to three days to take a sample, she said, “and that will give us information about what to do next.”

Susan Oppat can be reached by e-mail at soppat@annarbornews.com or at (734) 994-6823.