Husky Energy will continue using hydrogen fluoride, a highly toxic chemical, at the Superior, Wis., refinery that exploded and burned a year ago.
The Calgary-based company announced Tuesday it will spend more than $400 million to rebuild the refinery but said that ditching hydrogen fluoride would not be economically practical. Some Twin Ports residents and public officials have urged Husky to retool its refining process to eliminate the chemical.
Tanks of hydrogen fluoride were never breached during the conflagration, which was caused by an eroded valve. But large parts of Superior, a city of about 27,000, were evacuated because of fears of its release.