The Chicago Sun-Times has an article which states that:
Chicago Fire Department Aerial Tower Truck dual-rear wheels rest in a sidewalk construction site at the corner of Wabash and Congress Parkway Thursday, June 14, 2012 as fire department personel chock the back wheels to prepare it to be pulled out of the construction site.
The truck, Aerial Tower 1, was responding to a reported construction accident when it became stuck in soft ground near the site near East Congress Parkway and South Wabash Avenue, Fire Media Affairs Director Larry Langford said.
Reports indicate the truck got stuck about 6:30 p.m. Langford said the truck was out and back in service about 8:30 p.m.
The rear wheels of the truck appeared to have gotten stuck in a 2 or 3-feet deep trench along the roadway near the construction site.
“We worry about getting to the scene first and getting the truck out later,” said Langford, noting trucks have gotten stuck at construction sites or in soft areas before.
The fire department got the truck out without having to “resort to anything drastic,” Langford said. Nobody was injured and the truck was not damaged.
“There is a considerable weight on that apparatus,” Langford said. “Once you get them in there, they start sinking.”