Three Mile Island.
The Chernobyl Nuclear Power Plant underwent a level 7 event - the worst accident so far. The plant, located in the Soviet Union near Pripyat in Ukraine lost its number four reactor on 26 April 1986. A link to the Wikipedia article on the accident is provided.
Obviously depends on the severity of the accident. In the case of Three Mile Island (1979) there was no reason not to go on running the other unit on site, though the damaged one will never be restarted. In the case of Chernobyl (1986) the damage was so great that the whole site was shutdown, four reactors, and surrounding areas evacuated. This is a permanent result as far as I know.
Three mile Island near Harrisburg,PA March 28, 1979
Marcoule Nuclear Site was created in 1956.
The first event was not in the U.S., but it is the test site of Bikini Atoll in the Pacific Ocean. Tests that were done in the 1040s and 1950s have left their mark--still radioactive after all these years. The accident at the Three Mile Island nuclear power plant near Middletown, Pa., on March 28, 1979 brought awareness of the dangers of nuclear power. Although there was no lasting environmental effect, communication to the public did raise fears.
Chernobyl was the site of a nuclear power plant accident in 1986. According to Wiki, it was the worst disaster ever (and I seem to remember that being discussed that when it happened) and the only "level 7" disaster ever, whatever that means.
The site of a nuclear twin reactor plant, in Pennsylvania. In 1979 one of the reactors suffered a partial fuel meltdown, which caused great concern in the nuclear industry, but in fact did not cause significant radioactivity to be released.
Three mile island was the site of the worst nuclear 'accident' in america's history. The reactor went into meltdown - releasing radioactive material into the atmosphere.
As of 2021, Hanford nuclear site employs about 9,000 workers, with the majority of them working on cleanup efforts of the site.
the u.s. preform nuclear test at Nevada test site the u.s. preform nuclear test at Nevada test site the u.s. preform nuclear test at Nevada test site
In the US they're stored on site.