Storax Sedan, an underground 100-kiloton thermonuclear test conducted at Nevada Test Site on July 6, 1962 as part of Operation Plowshare, was a program designed to develop peaceful uses for nuclear explosives, such as canal and harbor building. Sedan left the largest man-made crater in the United States, displacing 12 million tons of earth and measuring 320 feet deep by 1280 feet in diameter. A circular area was leveled at the bottom of the crater to stop earth that might slide into the center, where sample drilling began eight months after the detonation.