Smoky fire forces evacuations at Wisconsin refinery; 11 injured

Authorities said a fire at a northwestern Wisconsin refinery where an explosion injured at least 11 people was out and people were being allowed back in their homes Thursday night after most of the city of Superior was forced to evacuate.

Douglas County officials posted an update saying the fire was extinguished but asking residents in the evacuation area to stay away from their homes for at least another two hours. The fire had poured thick clouds of noxious black smoke into the air after the explosion rocked the refinery. Schools and a hospital also were evacuated.

Authorities said a tank of crude oil or asphalt exploded about 10 a.m. at the Husky Energy oil refinery in Superior, a city of about 27,000 sharing a Lake Superior shipping port with nearby Duluth, Minnesota. That prompted them to order the evacuation of a three-mile radius around the refinery, as well as a 10-mile corridor south of it where the smoke was heading.

It was unclear how many people were being evacuated, but Mayor Jim Paine said most of the city was being evacuated. The refinery is in an industrial area, but there's a residential neighborhood within a mile to the northeast. The corridor downwind to the south of the refinery is sparsely populated. Schools in Superior and nearby Maple, Wisconsin, canceled classes Friday as a precaution.

Hospital officials said only one of the injured was seriously hurt, with what was described as a blast injury. No deaths were reported, and officials said all workers had been accounted for.

Thick, black smoke poured from the refinery hours after the explosion. Refinery manager Kollin Schade said the smoke was from burning asphalt so hot firefighters were unable to attack the fire to try to put it out. Emergency officials later said another tank had caught fire, too, though they didn't specify what was in it.

A four-person team from the U.S. Chemical Safety Board will investigate the blast. The board makes safety recommendations after serious chemical incidents.

The fire was put out about 11:20 a.m. but reignited, prompting police to urge residents living within an evacuation area to leave. Police blocked roads into the area around the refinery. Three schools and St. Mary's Hospital in Superior were being evacuated as a precaution.

A contractor who was inside the building told WDIO television the explosion sounded like "a sonic boom" and it happened when crews were working on shutting the plant down for repairs.