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.

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.

The blast at the Husky Energy refinery in Superior April 26 injured at least 13 people. The U.S. Chemical Safety Board says the initial explosion took place in the fluid catalytic cracking unit ...

FILE - This aerial image from video provided by KSTP-TV in Minneapolis shows smoke rising from the Husky Energy oil refinery after an explosion, April 26, 2018, at the plant in Superior, Wis ...

Image | HUSKY ENERGY-REFINERY/BLAST Caption: Dark smoke rises from a Husky Energy refinery following an explosion in Superior, Wis., on April 26. (Clint Austin/Duluth News Tribune/Reuters) ...

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 ...