UPDATE 9/15/2021
The cache is NOT behind the construction fencing and never was.
GPS signals are always challenging in large urban areas so the hint, geosense and satellite maps will be more helpful than your GPSr.
The cache is not at posted coordinates. It is the bonus final for the Chicago Public ArtWorks Adventure Lab. The final coordinates are near one of the sculptures and will be revealed when you complete that stop of the tour. No math, no counting, no gathering digits, just the coordinates.
Art is everywhere!
The waypoints for the Adventure Lab are provided as reference points on this cache to hopefully save you a little bit of flipping between apps.