Well, typically they use shape charges placed in critical load bearing beams, causing the structure to implode. The shape charges (maybe RDX) can be placed in places that allow control over how the building collapses minimizing chances for collateral damage.
I asked my construction birdie about a wrecking ball the night of the So Miss game. Thought it would be fun to watch. He said they no longer use them, they use big demolition excavators instead.
Since the lower deck will be retained, I expect the upper deck demolition will go gingerly.