Accidents
- Page ID
- 38932
Nuclear Reactor Accidents
Three Mile Island Reactor 2 (TMI-2) Accident on March 28, 1979, was the most serious in U.S. commercial nuclear power plant operating history. This link gives a summary of the events. The major layout of the nuclear reactor, the power generating building, and the cooling tower are shown here.
What Happened at Three Mile Island in March also gives a quick summary of the event.
The Chernobyl Reactor Accident
The Chernobyl Reactor The Soviet RBMK reactor has individual fuel channels, using ordinary water as coolant and graphite moderator. It evolved from reactors designed for plutonium production, and portion of it from the above link is shown here.
The accident at Chernobyl Unit 4 gives a rather detailed account.
Nuclear Reactor Accidents
In addition to the TMI-2 and Chernobyl accidents, the following accidents have been extracted from a report given by the IEEE site. But the site has been moved.
Reactor type | Location | Accident type | Year | Iodine-131 release, curies | Comments |
---|---|---|---|---|---|
Graphite-moderated, gas-cooled | Sellafield, Britain | graphite fire | 1957 | 20,000 | |
Graphite-moderated, water cooled | Chernobyl, Ukraine | supercriticality, steam explosion and graphite fire | 1986 | 7 million, perhaps far greater (see text) | Safety experiment went awry; total release 50 to 80 million curies or more; potential for continuing large releases exists |
Sodium-cooled fast breeder | Lagoona Beach (near Detroit) U.S. | cooling system block, partial meltdown | 1966 | release confined to the secondary containment | reactor was being tested for full power, but did not reach it; four minutes from indication of negative reactivity to meltdown |
Sodium-cooled fast breeder | Monju, Japan | major secondary sodium leak | 1995 | secondary sodium was not radioactive; reactor was in test phase; extensive sodium contamination in plant | |
Light water reactor, PWR type | Three Mile Island, near Harrisburg, U.S. | cooling system failure, partial meltdown | 1979 | 13 to 17 | secondary containment prevented release of millions of curies of I-131; accident developed over several hours |
Light water reactor, BWR | near Idaho Falls, U.S. | accidental supercriticality followed by explosion and destruction of the reactor | 1961 | 80 | small U.S. Army experimental reactor using HEU fuel; 3 operators were killed |
Heavy water cooled and moderated reactor | Chalk River, Canada | lack of coolant for a fuel element | 1958 | radioactivity apparently contained within building | Highest worker dose 19 rem |
Heavy water moderated, light water cooled, experimental reactor | Chalk River, Canada | inadvertent supercriticality and partial meltdown | 1952 | "There was some release of radioactivity" | President Jimmy Carter helped in the clean-up |
Heavy water moderated and cooled, CANDU type | Narora, Rajasthan, India | turbine fire; emergency core cooling system operated to prevent meltdown system | 1993 | apparently no release of radioactivity |
Sources: Chernobyl: NRC 1987 and Medvedev 1990; Sellafield: Makhijani et al. eds. 1995, Chapter 8; Three Mile Island: TMI Commission 1979 ; Lagoona Beach (Fermi-I) Alexanderson, ed. 1979 and Fuller 1975; Idaho: Horan and Gammill 1963 and Brynes et al. 1961; Monju: press reports; Chalk River: John May 1989 and Weinberg 1994; Narora, press reports. Full references are available here.
Contributors and Attributions
Chung (Peter) Chieh (Professor Emeritus, Chemistry @ University of Waterloo)