MADISON, Wis. (AP) — Federal regulators have determined that a lack of safeguards during a maintenance shutdown led to a 2018 explosion at an oil refinery in Superior.
The U.S. Chemical Safety Board released a final report last week on the April 2018 explosion at the refinery, Wisconsin Public Radio reported Wednesday.
Calgary-based Husky Energy owned the refinery at the time of the explosion. The blast injured 36 workers. Fears of a hydrofluoric acid leak forced 2,500 residents to evacuate. No acid leaked but a tank containing hot asphalt spilled 17,000 barrels into the facility. The asphalt caught fire, sending up a plume of black smoke that released thousands of pounds of flammable hydrocarbon vapor. The explosion caused about $550 million in damage to the refinery.
According to the CSB report, the refinery…
