Floodwater overwhelmed a pump at Exxon Mobil's (XOM) 275,000-barrel-per-day refinery in Joliet, Illinois, triggering cleanup efforts and adding to operational strains at the vital Midwest fuel supplier.
According to a filing on Thursday, crews have deployed a containment boom.
The site also flared on Wednesday, noted Patrick De Haan, head of petroleum analysis at GasBuddy, in a post on social media.
The pumping mishap compounds recent operational hurdles at the facility, which serves as a critical fuel supplier for the US Midwest and is capable of producing roughly 11 million gallons of gasoline and diesel daily.