City Adding New 1,4 Dioxane Monitoring Wells in Garden Homes Park

By The Ann Arbor Independent Editorial Team Last updated Oct 24, 2022

A July 2021 map of dioxane contamination in the Ann Arbor area’s groundwater. Pink is where readings are above 7.2 parts per billion, the state limit for dioxane in drinking water. The map shows the boundaries of the Gelman Sciences pollution source property off Wagner Road. There is a large, newly expanded zone through which the plume is allowed to spread through Ann Arbor toward the Huron River. In this area, groundwater use is prohibited. Courtesy of the State of Michigan

According to City of Ann Arbor officials, over the coming weeks, the City of Ann Arbor will be installing a pair of sentinel monitoring wells in Garden Homes Park. The cost is expected to be close to $333,000, plus a 10 percent contingency fee, according to information presented at a Sept. 2022 City Council meeting. The vote to spend the money for the new wells was unanimous.

These wells will allow the city to detect 1,4-dioxane in groundwater if the Gelman plume moves northeast and toward the City of Ann Arbor’s drinking water source at Barton Pond. These wells are in important part of the City’s strategy to protect the City’s water supply from contamination.

After drilling, two monitoring wells will be flush with the ground with a small concrete pad around each well. The ground surface and vegetation will otherwise be restored. Occasionally, these wells will be visited to collect a groundwater sample. This sampling will also be limited to a truck and small handheld equipment during normal business hours.

For more information, visit www.a2gov.org/A2H2O