From [0] : “Construction of the John Hancock Center began in 1965; however, was stopped in 1967 because the building kept sinking. Because of the John Hancock Center's lakeside location, 57 concrete caissons had to be sunk into 10 ft wide holes drilled 197-feet below grade into bedrock, resulting in the John Hancock Center having the deepest foundation of any building at the time.”
[0] - https://www.beck-technology.com/blog/how-did-they-build-that...
For instance the space needle is just on a giant hunk of concrete that is only 30ft deep. https://www.spaceneedle.com/history#:~:text=An%20underground....
But from memory most large buildings in the downtown area are on deep foundations in soils, not to bedrock.
Chicago's foundations are inherently unstable. IMO it makes being scientific about blaming "underground climate change" substantially more difficult. The journalist is out to lunch after strictly reporting on what these specific folks are saying and measuring.
If I didn't live and work there for years in the distant past, having spent many a nights drinking in bars below grade because of its history, I wouldn't know the amount of speculation the "science" reported in TFA really calls for.