Between 1961 and 1973 the United States carried out a series of nuclear tests designed to explore possible peaceful uses for all these damn nukes we had sitting around. Since we inexplicably were not yet dropping them on the Ruskies’ heads, the military-industrial complex looked for other excuses to blow shit to smithereens. Operation (or more commonly, Project) Plowshare consisted of nearly thirty test shots at locations around the country (mainly the Nevada Test Site, but tests were also conducted in New Mexico and Colorado) chiefly for the purpose of seeing how much dirt you could fling out of a hole with a big-ass atom bomb.
As it turns out, quite a bit! The Sedan shot, conducted on July 6, 1962, was the test of a 104 kiloton thermonuclear device. They dug a hole in the desert more than 600 feet deep and stuck the bomb in there, then set that shit off to see what would happen. The result was the largest man-made crater in the US, about 1200 feet across and 300 feet deep. However, another, less awesome result was a huge radioactive cloud which spread fallout in a narrow band across several neighbouring states. Sedan was either the worst or second worst (depending on how you measure it) test at the Nevada Test Site in terms of radionuclide dispersal. Of course, to be completely fair, the highest measured exposure levels from the fallout was about 0.35 millisieverts, which is close to the dose everybody receives naturally from the environment each year, and is an order of magnitude less than the dose a woman receives from having a mammogram (which is about 3 millisievert.) But, you know, fallout is FALLOUT, and that’s bad.
Sedan was a would-be test on a small scale of the type of excavation explosions that would be needed for Operation Chariot. In 1958, Edward Teller, the “father of the H-bomb,” decided Alaska needed a new harbor. And he was going to make them one using huge nukes! The harbor would be dug using 5 multi-megaton devices, set off in a precise configuration so that the end result would be a nice deep-water harbor. It was supposed to look something like this:
Pretty awesome, huh? Anyhow, as you might have guessed, this plan was never realized, partly because of the always-present fear of fallout, but mainly because nobody could figure out what to do with the harbor once it was created anyhow. There wasn’t really any need for one in that area, and the old “build it and they will come” philosophy wasn’t gaining much traction.
One of the less crazy of the Plowshare tests had to do with setting off nukes in deep underground natural gas fields, so as to stimulate the flow of gas from “tight” formations. As it turns out, this actually works, and increased natural gas flow resulted from several test shots in Colorado. However, a major drawback put the kibosh to the whole plan–the gas that was extracted from the fields after the nuclear detonations was too radioactive for safe use.
Over the course of 12 years, the US spent close to $800 million on Project Plowshare tests, with little to show for it except a big hole in the desert. Thus ended the great “blowin’ up shit for peace!” experiment.