TODD RICHMOND
Associated Press Writer

ST. ANNA, Wis. - A trash bin outside a rural Wisconsin foundry exploded after firefighters sprayed water on it, killing one volunteer firefighter and injuring eight others, authorities said Wednesday.

About 20 members of the St. Anna Volunteer Fire Department responded to the fire outside Bremer Manufacturing Co.'s plant on Tuesday night, department Capt. Adam Schuh said. About 15 minutes after they began to fight the fire the bin blew up.

"After that, it was just chaos. Everybody was yelling 'We need ambulances!'" Schuh said at a news conference Wednesday.

Thirty-three-year-old firefighter Steven Koeser was killed. The other firefighters suffered injuries that included burns and ringing ears, according to a statement from the fire and sheriff's department and state investigators.

All but one had been treated and released from the hospital by mid-afternoon Wednesday.

U.S. flags flew at half-staff around the area Wednesday. Schuh choked back sobs as he spoke about Koeser, calling him "our fallen brother."

According to its Web site, Bremer specializes in producing aluminum sand castings for other manufacturers. Bremer's Web site says it employs 120 people and melts about 375,000 pounds of aluminum a month.

A Calumet County Sheriff's deputy noticed the trash bin on fire outside the plant around 7:30 p.m. Sheriff's Investigator Mark Wiegert said warm byproducts from the plant's manufacturing process likely ignited the fire.

When firefighters arrived, they sprayed water on the fire, which caused a reaction that led to the explosion, the joint statement said.

State Justice Department Special Agent Mike Rindt, who is investigating the fire for the state fire marshal's office, said when water hits certain metals hydrogen gas is released. He did not elaborate, saying tests continue.

Bremer president Tom Dolack said the trash bin contained scrap aluminum.

Roger Brandt, 77, who lives about a quarter mile from the plant, said the explosion shook the windows in his house.

Schuh said Koeser had 15 years of experience with the fire department. No one was afraid to enter a burning building with him, Schuh said, his eyes welling up with tears.

"He died doing what he loved," Schuh said.

A man who answered the door at Koeser's parents' home in St. Anna said no one wanted to talk.

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