Amtrak leaders say pollution from the building threatens Union Station commuters.
The old Chicago Main Post Office may be on the brink of a new, massive redevelopment.
The building has sat empty for nearly 17 years and some even call it the city's Incredible Hulk, but investor Bill Davies, who gained control of the property in 2009, has big plans for the property.
In plans unveiled Tuesday, Davies wants to turn the landmark building into a mostly residential and parking complex, according to the Chicago Sun-Times, and envisions the building being the centerpiece for surrounding hotel rooms, stores and offices.
In broad outlines the plan calls for 2,900 rental housing units, 800,000 square feet of retail space and 525,000 square feet for offices, as well as 320 hotel rooms and 5,700 parking spaces, the Sun-Times reports.
It all would cost about $1.2 billion.
Joseph Antunovich, the architect hired for the job, told the Sun-Times he is confident the building could become the neighborhood shopping destination near the river.
At this point, though, it's all part of a proposal. Legal clearance is still needed followed by funding. Davies said he hopes to attract international investors to pay for the project and says a number of investors already have shown interest.
The scale of the building also would be suitable for a Chicago casino as part of a recently vetoed gambling expansion plan. There is speculation it could happen if the new gambling bill gets through Springfield and past the governor's desk.