Air Excavation, also known as airvac, pneumatic or air-knife excavation, uses compressed air to break up the ground materials before siphoning them through a vacuum hose. This process’s unique ability to backfill dry soil and debris means there’s no need to transport or dispose of wet, muddy material after digging. And because air compressors provide for an infinite supply of the pressure needed to dig, you don’t have to worry about “refilling” during the excavation process. Air is also nonconductive, which can make this method a more suitable choice when working around live electrical wires.