Ameren crews are preparing for an excavation project to remove potentially dangerous chemicals from the soil at the former Ameren headquarters building in Columbia.
On Wednesday, crews were demolishing the rest of the building near Ash and Orr Street.
Before it was Ameren headquarters, the site was used to manufacture gas dating back to the Civil War times. The site was abandoned in the 1930s and since then, the leftover waste has leaked into the soil.
Ameren officials told ABC 17 News gas used to be stored at the site in underground holders. The holders, however, were put in the ground inside storage units made of bricks and mortar, which are not long-term materials.
"There are tars and oils, and tars and oils have different types of chemicals and the one we're mostly concerned about is benzine, because that's a human carcinogen and it's also something that's very volatile," said Warren Mueller with Ameren Services. "There's benzine in gasoline."
Ameren will monitor the cleanup closely to make sure none of the hazardous chemicals get into the air. Crews will put up a tent covering the area to control the contaminants.
"We'll pump the air from inside that tent through the big, carbon filters and that way we'll control all the emissions from the most heavily contaminated part of the site," Mueller said.
He told ABC 17 News the most contaminated part is under the old building's foundation. He said crews will continue to monitor the air quality even after it has passed through the filter.
"There will be three devices collecting air at this point," Mueller said. "We also have somebody who is walking around the perimeter. They'll be using handheld instruments, and again, they'll be monitoring for volatile compounds and particulates."
Ameren said Columbia residents don't need to worry about their safety.
"We're making sure that this project is going to be done in a completely safe manner and we've done many of these before, so we're using experienced contractors and they are familiar with this material and how to properly excavate and manage it," Mueller said.
Ameren said this is a voluntary cleanup, and because the plan is for the land to be used for another purpose, they want it to meet environmental standards.
Ameren said they expect the project to be completed in July.