A massive fire at the Chemtool Inc. plant in Rockton, Illinois, forced the evacuation of everyone living within one mile of the facility on Monday. The blaze consumed the plant, sending huge plumes of grey smoke into the sky, NBC News reports. “We’re thinking that this is going to be a several-day event to have all of this product burned off. And that’s the best thing we can do right now,” said Rockton Fire Chief Kirk Wilson. The plant continues to burn despite being controlled by firefighters who fear that using water from the nearby Rock River could cause an “environmental disaster” in the Mississippi River tributary. A statement from Chemtool, which lists Rockton as its headquarters, said that all of its employees at the plant are safe and accounted for. “Our concern right now is for the safety of all our employees and the surrounding community,” the statement read. So far, the cause of the fire is unknown.