Leaking underground storage tanks that are scattered across Chicago and its suburbs may be leaving toxic patches of soil in neighborhoods around northern Illinois.
Approximately 21,150 underground storage tanks (UST) are known to exist within city limits, according to data provided to NBC5 Investigates by the city of Chicago, and approximately 3,353 leaking tanks have been reported to Chicago's Department of Public Health as of last year. City officials estimate nearly 1,800 still require clean up. Cleanup is the responsibility of the property owner/perator and managed by the Illinois EPA. CDPH said it inspects sights following cleanup to ensure compliance.
One known contaminated area sits on land designated for a proposed school on Chicago's southeast side. The school would be used to relieve overcrowding at Gallistel Academy and Jane Addams Elementary. But the planned site at 104 and Indianapolis Avenue has been found to contain a small, but still significant reading of benzene, a known carcinogen, according to the Illinois EPA.
"That will be a big question mark and a big concern for folks having their children come here and being exposed to that," said Jose Garza, the chair of the Local School Council for Gallistel Academy.
A spokesperson for the Illinois EPA said the contamination at the proposed school site leaked from a 5,000 gallon gasoline tank.
The city's Public Building Commission said, however, it is creating a comprehensive remediation plan to ensure the safety of everyone who uses the school. The plan will need to be approved by the Illinois EPA.
The Chicago Department of Public Health permits and inspects all underground storage tanks under the supervision of the Office of the State Fire Marshal.
"If it's a registered tank, it's got leak detection and leak prevention. So we will know about it," said Fred Schneller, the OSFM's division manager for petroleum and chemical safety.
Leaking oil and gasoline can pollute water and streams. The OSFM said in some rare cases leaking tanks can cause explosions.
The OSFM issues violation notices to owners of non-compliant USTs. A total of 7,448 violations were issued in the Chicago metropolitan area, excluding within Chicago city limits, since 2003.
"Typically we get compliance in 60 days," Schneller said.
But city and state statistics only include commercial underground storage tanks, similar to those under gas stations. It's not known how many residential tanks are buried under Chicago and its suburbs. Older heating oil tanks buried across the country do not require registration.
"They were left behind by people who converted from heating oil to natural gas," said David Streich of Chicago Tank Removal.
Streich said his business removes more than 400 storage tanks a year. He also collects soil for testing.
"These tanks are 80 to a 100 years old and steel returns to its natural state, which is iron ore," Streich said. "They all corrode and so they will continue to leak."
State law requires property owners to disclose their tanks before a potential sale.
"They need to make it known because it does present the possibility for hazard and danger," said James Votanek, president of the North Shore-Barrington Association of Realtors.
The Illinois EPA keeps track of reported leaks in a database. Search by address to see a past or present violation and its status.