"On a warm morning in April, workers at a Wisconsin oil refinery were conducting a routine shutdown for maintenance. Suddenly, a gasoline cracking unit exploded, and the workers watched in horror as a huge fireball ripped through the plant. They ran for their lives, barely escaping the blast.
Debris from the explosion ruptured a tank, which spilled more than half a million gallons of hot asphalt that burst into flames and burned for nine hours. Black smoke spread over the port town of Superior. Eleven workers were injured, and about 40,000 people were evacuated from nearby homes and schools.
Within 24 hours of the explosion at the Husky Energy Inc. refinery, a small team of federal investigators arrived. Their mission, Superior Mayor Jim Paine reassured residents, was to “find out what happened and how we prevent it in the future.”"
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