Project Plowshare

The 1962 “Sedan” plowshares shot displaced 12 million tons of earth and created a crater 320 feet (98 m) deep and 1,280 feet (390 m) wide

“Project Plowshare was the overall United States program for the development of techniques to use nuclear explosives for peaceful construction purposes. The program was organized in June 1957 as part of the worldwide Atoms for Peace efforts. As part of the program, 31 nuclear warheads were detonated in 27 separate tests. A similar program was carried out in the Soviet Union under the name Nuclear Explosions for the National Economy. Successful demonstrations of non-combat uses for nuclear explosives include rock blasting, stimulation of tight gas, chemical element manufacture, unlocking some of the mysteries of the R-process of stellar nucleosynthesis and probing the composition of the Earth’s deep crust, creating reflection seismology vibroseis data which has helped geologists and follow-on mining company prospecting. The project’s uncharacteristically large and atmospherically vented Sedan nuclear test also led geologists to determine that Barringer crater was formed as a result of a meteor impact and not from a volcanic eruption, as had earlier been assumed. This became the first crater on Earth definitely proven to be from an impact event. Negative impacts from Project Plowshare’s tests generated significant public opposition, which eventually led to the program’s termination in 1977. These consequences included tritiated water (projected to increase by CER Geonuclear Corporation to a level of 2% of the then-maximum level for drinking water)^[6] and the deposition of fallout from radioactive material being injected into the atmosphere before underground testing was mandated by treaty. … Operation Plowshare ‘started with great expectations and high hopes’. Planners believed that the projects could be completed safely, but there was less confidence that they could be completed more economically than conventional methods. Moreover, there was insufficient public and Congressional support for the projects. …”
Wikipedia
Want To Trigger A Nuke In Colorado? Well, Thanks To Project Rulison 50 Years Ago You Need To Ask Voters First
Ploughshares Fund
YouTube: Operation Plowshare

Photo, taken at ground zero shortly after the detonation (Sept. 10, 1969), shows the post-shot briefing that was held for some of the observers.