Scientists want to use an unconventional method to remove pollution at former General Motors properties near Lansing where an underground plume of chemicals is creeping toward drinking water wells.
The Revitalizing Auto Communities Environmental Response Trust controls the former GM plants. It is proposing a remediation method called "biosparging," which removes pollution by injecting air into groundwater. The method encourages bacteria to consume 1,4-dioxane, an industrial chemical that GM used to clean oil off car parts.
Should the trust gain state approval, the project would be among the first and likely the largest to use the method, the Lansing State Journal reported . It's unclear how much the project would cost, but engineers said it could take six to 12 years to fully clean the water.
The pollution was discovered after the trust was established by the federal government to take over the GM sites following the company's bankruptcy reorganization in 2009. The dioxane plume is located under two former GM plants in Lansing Township and Lansing.
Dave Favero, deputy cleanup manager for the Michigan properties, said dioxane is very soluble. If dioxane is in oil, as it was used at the GM plants, "it leaches out and starts to migrate with the groundwater," he said.
Long-term exposure could lead to liver, kidney and reproductive problems and possibly cancer, according to the Environmental Protection Agency.
The Lansing-area plume is within the Lansing Board of Water and Light's wellhead protection area for some of its drinking water wells. Up to 10 of the utility's wells are downstream from the polluted groundwater.
The utility started monitoring for dioxane in 2015, and found a small amount within the limits of what the EPA considers safe. The utility hasn't monitored dioxane levels that exceed the EPA's safe limit yet.
The trust will need to get approval from state environmental regulators. Scientists and engineers could begin installing biosparging wells this year if the plan is approved.