Sheriff's deputies shut down a seven-mile stretch of Arsenal Road after an oily substance escaped into the air from the Channahon ExxonMobil plant Friday morning.
Arsenal Road was closed from Interstate 55 east to Baseline Road and will stay closed for the remainder of the day, according to the Will County Sheriff's Department.
The leak was cut off but the cleanup was continuing Friday afternoon.
Deputy Chief Ken Kaupas of the sheriff's department said the substance is not hazardous but recommended washing cars exposed to it.
"You don't want to drive through this stuff," said Kaupas, who identified the substance as "oil or diesel."
The sheriff's department advised citizens to submit car wash receipts to ExxonMobil for reimbursement.
Police officers from various agencies, as well as emergency management personnel and workers from ExxonMobil, responded to the incident, the sheriff's department said.
The sheriff's department said the company is setting up a hotline for citizens who have incurred costs for clean-up.
ExxonMobil spokeswoman Claire Hassett released a statement about the incident just before 3 p.m.
"The ExxonMobil Joliet Refinery in Channahon experienced a release of hydrocarbon through a safety release system on one of its process units this morning," Hassett said in an email. "ExxonMobil immediately deployed industrial hygienists to monitor the area and no health impacts have been identified. We are cooperating with the Will County Sheriff’s Department to ensure safe travel through the vicinity. We are very sorry for the inconvenience. There were no injuries, and refinery production has not been impacted."