They are drilling something like 86 piers for the structure that will be built above the parking garage to sit on. They use the giant drill bit to drill down 40 feet into the ground, and then concrete is pumped through the center of the drill bit to fill the hole as the bit is pulled up out of the ground. After the hole is filled with concrete, they shove rebar into the wet cement. It's an interesting process. The last photo is a panorama of the staging yard through the exhaust pipes on the parking garage.