We drill both 4" and 6" wells all over Middle GA.
After the well is drilled, steel pipe is lowered to the bottom of the well, inside the casing, in which compressed air is now blown. The air forces the drilling mud and water out of the well and onto the ground. Doing this forces an in-rush of water from around the well to enter the casing. This is done over a period of time to help clean the screen at the bottom, settle the disturbed area surrounding the well, and give the drillers a rough estimate of the amount of water that the well produces.