Bunker-busting nuclear weapon

Bunker-busting nuclear weapons, also known as earth-penetrating weapons (EPW), are a type of nuclear weapon designed to penetrate into soil, rock, or concrete to deliver a nuclear warhead to a target. These weapons would be used to destroy hardened, underground military bunkers buried deep in the ground. In theory, the amount of radioactive nuclear fallout would be reduced from that of a standard, air-burst nuclear detonation because they would have relatively low explosive yield. However because such weapons necessarily come into contact with large amounts of earth-based debris, they may, under certain circumstances, still generate fallout. Warhead yield and weapon design have changed periodically throughout the history of the design of such weapons. In general, these weapons deliver more "useful" destruction because unlike air bursts, the energy yield does not dissipate into the air.