Firefighters Battle Blaze On Roof Of Old Post Office

CHICAGO (CBS)--A faulty ventilation fan appears to be the cause of a fire that burned Friday night atop the old Main Post Office Building that straddles the Eisenhower Expressway.

The massive fan is one of 11 connected to shafts that ventilate at the top of the building, at 433 W. Van Buren St., which was vacated by the U.S. Postal Service in 1997, and auctioned off recently to a private developer, International Property Development.

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The fans made headlines a year ago because most did not work -- and allowed diesel soot to build up on the south platforms of the adjacent Chicago Union Station.

Amtrak and Metra have been working with building owners to correct that.  Last week, Amtrak and U.S. Sen. Dick Durbin (D-Ill.) criticized International Property Development for not moving faster to resurrect the fans.  Amtrak had threatened legal action.

Work was under way on three of the broken fans, although Deputy District Chief Tony van Buskirk said no one was in the building at the time.

"The one that actually we had a problem with today is a newer fan," he said.

Although the fire was small, van Buskirk said he took no chances.  He ordered 130 firefighters to the scene.

They controlled the fire with hand pumps and eventually used a tower ladder to hoist a hose line into place to douse the flames.