In the 1890s, a section of Aurora's Fox River shoreline that's soon to be RiverEdge Park was home to one of the key industrial uses of the time -- a factory that turned coal into gas.
Manufactured gas plants, as facilities of that kind were called, leave chemical residues in the ground long after they're shut down, environmental experts have found.
So before the site begins its next use as part of the park, it has to be cleaned up. ComEd is responsible for site remediation because one of its predecessor companies formerly owned the gas plant, spokesman Bennie Currie said.
An environmental cleanup firm hired by ComEd will begin removing possibly contaminated soil from a slice of the RiverEdge Park site at 330 N. Broadway Ave. in a couple weeks, Currie said. The process of removing the material and replacing it with clean soil to build the site back up to its current grade is expected to take three months.
The timeline of the work was moved up to accommodate RiverEdge Park construction, said Stephane Phifer, Aurora's planning and zoning director.
But the city and ComEd both knew the work had to be done at some point through the Illinois Environmental Protection Agency's Site Remediation Program.
"It's just part of cleaning up old industrial uses along the river," Phifer said.
When manufactured gas plants were shut down, their aboveground structures were demolished, but nothing was done about the materials that may have spilled or leaked underground during the process of turning coal into gas.
"Byproducts such as coal tar were sometimes left behind," Currie said. "The remediation work will remove the residues that remain from the historical manufacturing process."
Once the work is complete, ComEd and the city will submit documentation to the IEPA seeking a letter saying no further remediation is required, according to an agreement between the power company and the city.
The city council last week approved the agreement, which grants ComEd access to the site to complete remediation.
"The site in its current state poses no health risks," Currie said. "But we just want to ensure future uses of the site are not hampered by the material that's left there."