PHOTO GALLERY: DTE using odor controls as workers remove contaminated soil at former MichCon site in Ann Arbor

DTE Energy began a $3 million environmental remediation project this month on the property it inherited by acquiring MichCon.

The most intense part of the work at the site off Broadway Street began this week, as crews from Terra Contracting of Kalamazoo began digging out contamination from hot spots where underground structures left over from a manufactured gas industry still hold residues from years of burning coal and oil to make gas.

Five air monitors placed around the site check for levels of particulate matter, volatile organic compounds and methane as a safety precaution.

The dirt being removed may smell like creosote or mothballs, but officials from DTE have said the odor does not indicate there's a health risk.

To control odors from the site, workers use a floral-smelling masking agent sprayed through a Piian mist sytem during the day, said Shayne Wiesemann, senior project manager for DTE.

At night, workers apply a layer of Rusmar foam that creates a crust-like barrier over the exposed soils to keep the odor down.

Both measures are biodegradable and non-toxic, Wiesemann said. The company has not received complaints about the odor to date, Wiesemann said.

Dirt removed from the site is not considered to be hazardous waste and workers are trucking it to the Veolia Arbor Hills Type 2 Sanitary Landfill in Northville, where it likely will be dumped over the household trash as daily cover.