US EPA Region 5 has entered into an agreement with Peoples Gas Company to oversee the company's investigation of 11 former manufactured gas plant (MGP) sites in Chicago. Peoples Gas will investigate the extent and nature of contamination on each of the sites, and then evaluate potential cleanup options. This process is expected to continue through 2009. Final cleanup determinations will be made by EPA, in consultation with Illinois EPA, the City of Chicago and area residents.
All of the properties covered by the agreement are relatively close to the Chicago River, which was a transportation route when the manufactured gas plants operated. These facilities produced gas from coal from the mid-19th through the mid-20th centuries. After World War II, coal gas was phased out and replaced with natural gas for cooking and heating. Waste from these operations often included tar, oil, cinders and coke (coal residue). The material also usually contains polynuclear aromatic hydrocarbons, volatile organic compounds and heavy metals such as arsenic and lead.
Four of the MGP sites are clustered near Goose Island on the north side and five are on the south side along the river between Halsted St. and Ashland Ave.
Some excavation of contaminated soil is already under way at portions of three of the sites under Illinois EPA's voluntary cleanup program: 22nd Street, Hough Place and Pitney Court. This cleanup will continue under EPA and Illinois EPA oversight while the investigative work proceeds.