The explosion occurred on Monday morning around 7:30am.
An evacuation of the area was ordered by fire officials who feared potentially hazardous chemicals may have been leaked into the air. According to MyStateline.com, Chemtool produces fluids, lubricants and grease products.
Approximately 70 Chemtool employees were evacuated from the facility.
Rockton Fire Chief Kirk Wilson said the city’s HAZMAT teams conducted air quality tests and found that “there is no danger to air quality” at the ground level.
Prior to the tests, Mr Wilson said it was “strongly suggested” that 150 businesses and residents within the one-mile “danger zone” should leave the area.
Mr Wilson said the fire in the chemical plant could become an “environmental disaster” due to the release of harmful substances into the air.
One firefighter has been injured while responding to the incident. There are no other known injuries.
The Lubrizol Corporation, which owns Chemtool, released a statement on Monday addressing the blaze.
“We have confirmed all on site are safe and accounted for. Our concern right now is for the safety of all our employees and the surrounding community. As a precaution, authorities have evacuated residents in a one-mile radius of the site,” the company said.
The company said it was working to help solve the problem.
“We do not yet know what caused this incident, but we will be working with local authorities and with our own risk management team to determine what happened and identify any corrective actions. We will share more details as they are known,” the statement said.
A local middle school is being used as an evacuation site.
MyStateline.com spoke with an employee at the plant who said everyone escaped unharmed.
“Everybody that got us out of there – they were on top of it. We had plenty of time to get out. Everybody got out. It was pretty well organised,” the employee said. “There’s a lot of grease, oil and fluids in there. It’s gonna burn for a while. If it was going to explode, it would’ve already done it. Those small explosions that everyone’s seeing are drums of fluid or grease.”
The employee told the outlet that they were told a pipe that pumps hot grease along the ceiling from kettles in the facility broke, prompting the fire.
The company has not released a statement confirming the cause of the blaze.