In this case we are referring to an Auger Cast Piling, which is a column of reinforced concrete in the ground to provide a solid base on which to build. Here is a link to our sister company that makes pilings Xtreme's Auger Cast Piles
Xtreme's Auger machine drilling for the piling
When making a piling, after the hole is drilled, a concrete grout is pumped into the hole. In most cases there is an over pour of grout as they cannot be short. So the extra grout spills out around the top of the hole and is left to set.
The extra set grout cannot be left as they will usually tie the extended rebar into new grade beams, or other structures.
Typically you would wait a at least 3 days
Usually a jackhammer attached to an excavator is used to break up the concrete without damaging the piling. Also a skid steer mini loader is used to scoop up the broken grout and load it into trucks for haul out
The grout is crushed and recycled as road base
After pilings are installed there is typically excess concrete to break up and clear away
Piling cleanup requires jack hammers and skid loaders to clean up
Pilings after cleanup has been done, ready for grade beam forms and then pour