List of nuclear accidents
Notable Nuclear Accidents
- September 2, 1944 – A container of uranium hexafluoride explodes in the Oak Ridge transfer room, killing Peter N. Bragg, Jr and Douglas P. Meigs and injuring three others. A steam pipe explodes and the incoming water vapor combines with the uranium compound to form hydrogen fluoride, a dangerous acid, which is inhaled by all five. Bragg and Meigs die soon after from whole-body acid burns.
- August 21, 1945 – Harry K. Daghlian, Jr, working at Los Alamos Omega site, accidentally creates a supercritical mass when he drops a tungsten carbide brick onto a plutonium core. He quickly removes the piece, but is fatally irradiated in the incident, dying September 15.
- May 21, 1946 – Canadian physicist Louis Slotin manually assembles a critical mass of plutonium while demonstrating his technique to visiting scientists at Los Alamos, New Mexico. The device consists of two half-spheres of beryllium-covered plutonium, which can be moved together slowly to measure the criticality. Normally the device would be operated by machinery, but Slotin distrusted the devices and manually operated it by holding the upper sphere with his thumb inserted in a whole in the top like a bowling ball. In most experiments, a number of washers would be arranged to prevent the two hemispheres from falling together completely, but he had removed them. In order to slowly bring the two pieces together, he rested one edge on the lower sphere and rotated a slot screwdriver between the other edge to control the separation. At one point, the screwdriver slipped and the assembly went critical while he was still holding onto it. None of the seven observers received a lethal dose, but Slotin died on the 30th from massive radiation poisoning, with an estimated dose of 1,000 rad. This was dramatized in the movie Fat Man and Little Boy, except that the movie placed the event before the Trinity test—In reality, a device that Slotin had helped to assemble.
- February 13, 1950 - B-36 en route from Alaska to Carswell Air Force Base in Fort Worth, Texas develops mechanical difficulties. The crew dump the nuclear weapons off British Columbia then abandon ship. The high explosives detonate on impact.
- April 11, 1950 – A B-29 bomber crashes three minutes after takeoff from Kirtland Air Force Base in New Mexico. A nuclear bomb with no detonators installed is on board at the time of the crash; it's casing is destroyed, but the weapon does not go off.
- November 10, 1950 - B-50 returning one of several US Mark IV bombs secretly deployed in Canada has engine trouble and jettisons the weapon at 10,500 feet. The bomb, carrying some uranium but not its plutonium core, is set to self-destruct at 2500' and dropped over the St. Lawrence River off Rivière du Loup, Quebec. The explosion shakes area residents and scatters nearly 100 pounds (45 kg) of uranium.
- December 12, 1952, Chalk River, Canada - first serious nuclear disaster in the NRX reactor. A massive power excursion destroyed the core, resulting in a partial meltdown. A series of hydrogen gas explosions threw the four-ton gasholder dome four feet into the air where it jammed in the superstructure. Thousands of curies of fission products were released into the atmosphere, and a million gallons of radioactively contaminated water had to be pumped out of the basement and "disposed of" in shallow trenches not far from the Ottawa River. The core was buried. Jimmy Carter, then a nuclear engineer in the US Navy, was among the cleanup crew.
- April 26, 1953 - Albany-Troy rainout, probably from Simon test. Ground radiation averaged about 50 Ci/km²; some puddles register 270 nCi/L, nearly 3000× the AEC limit. There is an even worse rainout in June.
- May 19, 1953 - The U.S. Government detonates the 32-kiloton bomb "Harry" at the Nevada test site. The bomb later became known as "Dirty Harry" because of the tremendous amount of offsite fallout generated by the bomb.  Winds carried fallout 135 miles to St. George, Utah, where residents reported "an oddly metallic sort of taste in the air."  A 1962 AEC report found that "children living in St. George, Utah may have received doses to the thyroid of radioiodine as high as 120 to 440 rads." 
- 1954 Off the Delaware/Maryland coast - The US Submarine Seawolf scuttles an experimental sodium-cooled reactor in 9,000 feet of water. At 33 kCi it's likely the most radioactive single object ever deliberately sunk, and has not been retrieved as of 2003. The reactor had problems with corrosion from the coolant, and was replaced by a conventional light-water reactor.
- March 1, 1954 During the early morning of March 1st, a Japanese Fishing boat, the Fukuryu Maru, or "Lucky Dragon," and its crew witnessed what they thought was the sun rising to the west of them as they sailed in the Pacific Ocean. What they were in fact witnessing was the 12 Megaton detonation of the Hydrogen "Bravo" bomb at the Bikini Atoll, 85 miles away. Several hours later, white ash began to fall like snow onto the boat. Many of the crew members began gathering the ash into bags as souvenirs. Before the sun set, the entire crew became ill. (The 86 residents of Rongelap Atoll had similar experience from their inch-plus of deadly snow.) The 23 crew members were hospitalized in Japan and one later died of kidney failure, due to exposure to radiation. The incident caused a rift in relations between Japan and the United States because the US did not warn Japan or any other country of the bomb's testing, leaving the Lucky Dragon exposed to the fallout. (In partial mitigation, the device yielded about 2½× what was predicted because of an overlooked reaction; the US expanded its exclusion zones in later tests.) The US issued an apology and paid 2 million US dollarss in compensation.
- 1955 - unexpected wind shift drops test fallout on Las Vegas
- November 29, 1955 - Operator error destroys three-year-old experimental breeder reactor EBR-1.
- November 22, 1955 - Soviets test the first weaponised fusion device, 1.6 Mt. Atmospheric refraction causes unexpected blast damage, killing three.
- March 10, 1956 - Somewhere en route to a rendezvous with an Air Force tanker flying over the Mediterranean Sea, a B-47 from MacDill Air Force Base in Tampa, Florida disappears without a trace. The plane is carrying two nuclear capsules at the time of the incident.
- July 2, 1956 - Nine individuals are injured after two explosions destroyed a portion of Sylvania Electric Products' Metallurgy Atomic Research Center in Bayside, Queens, New York.
- July 26, 1956 - A US B-47 practicing landings at Lakenheath Air Base in Suffolk, England skids into a nuclear storage "igloo" with three Mark VI bombs inside. The resulting fire is extinguished without explosion, although a secret cable by US 7th Air Division General James Walsh in Britain remarks that the bombs were "knocked about," and, "Preliminary exam by bomb disposal officer says a miracle that one Mark Six with exposed detonators sheared didn't go."
- May 22, 1957 - Land grants of University of New Mexico, near Albuquerque, New Mexico. A bomber accidentally drops a 10-megaton hydrogen bomb. The trigger explosive detonates, creating a 12-foot deep crater 25 feet across. Some radiation is detected.
- July 28, 1957 - C-124 Globemaster with 3 nuclear weapons and a nuclear capsule from Dover AFB loses power in two engines. Two weapons are jettisoned somewhere off Rehobeth DW and Cape May/Wildwood NJ; they are never found.
- 1957 Keleket Co. - A capsule of radium salt bursts. This causes a five-month decontamination costing $250,000. The capsule was used to calibrate the radiation-measuring devices produced there.
- September 11, 1957 - Major fire at Rocky Flats weapon mill 27 km from Denver begins in a glovebox and spreads through the ventilation system into the stack filters. Plutonium (among lesser evils) is released, but no one is sure how much; estimates range from 25 mg to 250 kg.class="external">[2
September 29, 1957 - Cooling system failure resulted in a nuclear waste storage tank explosion at Mayak, a spent nuclear fuel reprocessing facility near Chelyabinsk, Russia, releasing some 20 MCi and subjecting (by various estimates) 124,000 to 270,000 people to dangerously high levels of radiation. Of these, only 7,500 were evacuated, most of them too late to prevent dangerous levels of exposure. A series of less prominent accidents preceded and followed this meltdown, in addition to a polluted water supply for people remaining in the area. More than 500,000 inhabitants of the region have been exposed to radiation as a result.
October 7-11, 1957 - Windscale Pile No. 1 at Sellafield north of Liverpool, England begins a process dubbed "annealing" to release Wigner energy from graphite portions of the reactor. Technicians mistakenly overheat the reactor pile because poorly placed temperature sensors indicate the reactor is cooling rather than heating. A fire results in the following days and is finally extinguished on the 11th, but it is discovered that the air-cooled reactor had spewed radioactive gases throughout the surrounding countryside. Milk distribution is banned in a 200 square mile area around the reactor. Over the following years, Pile No. 1 and neighboring Pile No. 2 are shut down, although nuclear decommission work resumes in 1990 and continues at least through 1999. The incident, classified as the same scale as Three Mile Island, is later blamed for dozens of cancer deaths.class="external">[2class="external">[1
January 31, 1958, U.S. Air-Force Base, 90 miles N.E. of Rabat, Morocco - A B-47 with a fully-armed nuclear weapon crashes and burns for 7 hours. The Air Force evacuates everyone within 1 mile of the base. Many vehicles and aircraft were contaminated. Moroccan officials were not notified.
February 5, 1958 – A damaged B-47 flying off the coast of Georgia near Tybee Island jettisons a weapon lacking its nuclear core from 7200 feet after attempting to land three times at Hunter Air Force Base. The plane had suffered a collision with an F-86 during simulated combat near Savannah, Georgia, and could not land safely with the heavy bomb on board. The bomb is never recovered.
February 28, 1958 – At a US airbase at Greenham Common, England, a B-47 has a fiery crash. Scientists working for the Atomic Weapons Research Establishment in Aldermaston in 1960 discover high concentrations of radioactive contamination at the base, pointing toward the conclusion that a nuclear warhead was involved in the crash. However, the US government has never confirmed such speculation.
1958 - unexpected wind shift drops test fallout on Los Angeles
1958 - Military reactor near Chelyabinsk relases radioactive dust. 12 villages evacuated.
1958, Chalk River, Canada several metallic uranium fuel rods in the NRU reactor overheated and ruptured inside the core. One of the damaged rods caught fire and was torn in two as it was being removed from the core by a robotic crane. As the remote-controlled crane passed overhead, carrying the larger portion of the damaged rod, a three-foot length of burning uranium fuel broke off and fell into a shallow maintenance pit. The ventilation system was jammed in the "open" position, thereby contaminating the accessible areas of the building as well as a sizable area downwind from the reactor site. A relay team of scientists and technicians eventually extinguished the fire by running past the maintenance pit at top speed wearing full protective gear, dumping buckets of wet sand on the burning uranium fuel.
March 11, 1958, Hunter Air Force Base, Georgia - A B-47 en route to an overseas base drops an unarmed nuclear weapon into the yard of Walter Gregg and his family in Mars Bluff, South Carolina, near Florence, South Carolina. The trigger explodes and destroys Gregg's house, injuring six members of his family. The blast forms a crater 60 feet wide and 30 feet deep. Five houses and a church are also damaged. Five months later the Air Force pays the Greggs $54,000 of his estimated $300,000 loss. Residents carried away radioactive pieces of the bomb for souvenirs, which had to be retrieved by the Air Force cleanup crew.
November 4, 1958 - B-47 bearing nuclear bombs burns in flight, crashing in Texas.
December 30, 1958 - A critical mass of plutonium solution is accidentally assembled during chemical purification at Los Alamos. The crane operator dies of acute radiation sickness. The March, 1961 Journal of Occupational Medicine prints a special supplement medically analyzing this accident. Hand-manipulations of critical assemblies are abandoned as a matter of policy in U.S. federal facilities after this accident.
1959 Santa Susana Field Laboratory near Simi Valley, California - A sodium-cooled reactor suffers a partial core meltdown.
July 1959 - small meltdown in San Fernando valley releases radiation
October 1959 - One killed and 3 seriously burned in explosion and fire of prototype reactor for the USS Triton at the Navy's training center in West Milton NY. The Navy stated "The explosion?was completely unrelated to the reactor or any of its principal auxiliary systems," but sources familiar with the operation claim that the high-pressure air flask that exploded was to feed a crucial reactor-problem backup system.
October 15, 1959 - B-52 with two nuclear bombs collides with KC-135 tanker and crashes in Kentucky
- June 7, 1960 McGuire Air Force Base, New Egypt, New Jersey A helium tank explodes, rupturing the tanks of a BOMARC-A cruise missile. The fire melts the missile. The plutonium released from the nuclear trigger contaminates the facility and ground water.
- 1961 - The USS Theodore Roosevelt attempts to dump the depleted resin from its demineralization system (used to remove dissolved radioactive minerals and particles from the primary coolant loops of submarines). The ship is contaminated when wind blew the resin back onto the ship.
- January 3, 1961 National Reactor Testing Station, Idaho Falls, Idaho - The SL-1, an experimental reactor, had a criticality incident, with a steam explosion and a severe dispersal of radioactive material, killing three workers at the installation. The radiation is contained. The experimental portable reactor had manually-moved control rods. Moving a single rod could cause the criticality incident. The rods were known to jam in the lightweight aluminum housing. Some investigators believe that a rod stuck and then suddenly released, causing the criticality incident. One worker was found pinned to the ceiling by a control rod, apparently driven by the steam.
- January 24, 1961, 12 miles north of Seymour Johnson Air Force Base, Goldsboro, North Carolina - A B-52 bomber explodes in mid-air. It releases two hydrogen bombs. Five crewmen parachuted to safety, three die. One bomb parachutes down, intact. The other plunges into mud. The area remains fenced, and tested regularly for radiation, although the state says that no radiation above background is present. See: [Broken Arrow: Goldsboro, NC " class="external">http://www.ibiblio.org/bomb/].
- March 1961 - B-52 with nuclear weapons crashlands near Yuba City California. (The string of such accidents the past few years prompts Kennedy to have the weapons' safety interlocks improved.)
- December 10, 1961 - An underground test nuclear explosion releases clouds of radioactive steam, causing several New Mexico highways to be closed.
- 1962 - Czech study proves the uranium mill near Ceske Budejovice has caused the loss of 80% of local cattle by leukemia and deformities. Budweiser gets its hops from the same area.
- April 10, 1963, east of Boston, Massachusetts - The nuclear submarine USS Thresher sank during sea trials with 129 men aboard. A year earlier, just before the end of its refit interval, the boat had been abused in a munitions test where it literally tried to approach explosions as closely as possible. The boat was refitted afterward, and sank on its sea trials. In a show of poor planning, the sea trial was conducted where the bottom was below the hull's crush depth. In the yard, destructive tests of a few silver-soldered pipe connections had failed. At the time, nondestructive testing was unknown, and no test records were available. The investigators believed that the sinking was caused by the failure of a major through-hull silver-soldered connection, such as a secondary-loop cooling inlet, and that the reactor and its design was not responsible. The reactor was not recovered.
- May 1963 - Mandan North Dakota records the highest milk concentration of strontium-90 anywhere in the US ever (as of 2003). It probably originated in the highly-secret Hanford lab.
- January 13, 1964 - B-52 with two nuclear weapons crashes near Cumberland Maryland
- April 1964 - US nuclear-powered navigational satellite burns in the atmosphere, releasing 17 kCi of Pu-238
- July 24, 1964 - An accident at a commercial nuclear fuel fabrication facility in Charlestown, Rhode Island left one person dead.
- January 1965 - Accident at Livermore releases 300 kCi
- October 1965 - fire at Rocky Flats exposes a crew of 25 to up to 17× the legal limit
- December 5, 1965 - Nuclear-armed plane falls off USS Ticonderoga into 4.9 km of water off Japan.
- January 17, 1966, Palomares, Spain - During over-ocean in-flight refueling, a B-52 collides with an Air Force KC-135 jet tanker. Eight of the eleven crew members are killed. The KC-135's 40,000 gallons of jet fuel burn. Two hydrogen bombs rupture. The radioactive particles disperse over farms. An intact bomb lands near Palomares. The fourth bomb was lost at sea 12 miles off the coast. A search involving three months and 12,000 men recover it. 1,500 tons of radioactive soil and tomato plants were shipped to a nuclear dump in Aiken, South Carolina. The U.S. settled claims by 522 Palomares residents for $600,000. The town got a $200,000 desalinizing plant.
- September 1966 - Pu fire at Livermore
- October 5, 1966 - Near Detroit, Michigan a sodium cooling system malfunction caused a partial core meltdown at the Enrico Fermi demonstration nuclear breeder reactor. The radiation was contained. This incident is the basis of the controversial polemic We Almost Lost Detroit by John G. Fuller.
- 1967 - Livermore leaks plutonium into San Francisco's sewers for three weeks; the city used dried sewage as fertilizer
- January 22, 1968, 7 miles S. of Thule Air Force Base, Greenland. A fire breaks out in the navigator's compartment of a B-52, which then crashes, scattering three hydrogen bombs on land, and dropping one into the sea. Contaminated ice and airplane debris were buried in the U.S. Bomb fragments were recycled by Pantex, in Amarillo, Texas. Danes were outraged (Greenland is a Danish possesion.) Denmark forbids nuclear weapons on its territory. Denmark had massive demonstrations against the U.S. One warhead was recovered by Navy Seals and Seabees (U.S. naval engineers) in 1979, An August 2000 report suggests that the other bomb remains at the bottom of Baffin Bay.
- May 21, 1968 - The USS Scorpion, a nuclear-powered attack submarine carrying two Mark 45 ASTOR torpedoes with nuclear warheads, was lost with 99 aboard. The nuclear material has not been recovered. The submarine has been photographed at the ocean bottom, and the U.S. Navy periodically monitors the location for radioactivity. Supposedly there has been no plutonium leakage to date.
- December 8, 1968, Nevada - 30-kt "underground" Plowshare test Schooner leaks radiation which drifts across Canadian border, a treaty violation
- December 9, 1968, Nevada - An underground test of nuclear explosives releases clouds of radioactive steam.
- January 21, 1969 - A coolant malfunction from an experimental underground nuclear reactor at Lucens Vad, Switzerland, released a large amount of radiation into a cavern, which was then sealed.
- May 11, 1969 - 5 kg of Pu burns at Rocky Flats. Hundreds of railway cars are used to transport the contamination to Idaho Falls, where it is left in unlined trenches over one of the US' most significant aquafirs
- May 16, 1969, San Francisco, California, while being fitted the USS Guitarro, a nuclear submarine, sank because a forward compartment flooded.
- July 24, 1969, The AEC's Nuclear Trigger Assembly Facility, Rocky Flats, Colorado - a serious fire suspends U.S. missile production. Areas downwind were contaminated by plutonium. Several factory buildings became uninhabitable, were dismantled and buried.
- December 18, 1970 Baneberry underground test vents 6.7 MCi through a fissure in the rock. Fallout drifted into Canada, violating the 1963 test-ban treaty.
- November 19, 1971 Northern States Power Company, Monticello, Minnesota - A nuclear power plant's water storage facility overflowed, releasing 50,000 gallons of radioactive waste water into the Mississippi River. Some radioactive substances entered the St. Paul water system.
- December 12, 1971, Thames river, near New London, Connecticut - Radioactive coolant water was being transferred from the submarine U.S.S. Dace to the sub tender U.S.S. Fulton when five hundred gallons were spilled.
- 1972, Nuclear Fuel Reprocessing Plant, West Valley, New York. After six years, the fuel reprocessing plant was closed. It left buried leaking tanks containing 600,000 gallons of high-level wastes. The waste contaminated Lake Erie and Lake Ontario.
- March 1972 - Senator Mike Gravel of Alaska submitted information to the Congressional Record. A routine check of a nuclear power plant showed radioactivity in the building's water, including the plant drinking fountain, which had been cross-connected with a 3,000 gallon tank of radioactive water.
- December 1972, Plutonium fabrication plant, Pauling, New York - A major fire and two explosions caused plutonium to contaminate the plant and grounds, resulting in its permanent shutdown.
- 1974 Isomedix Co, New Jersey - Workers report that radioactive water was flushed down toilets. The sewer pipes were contaminated. That year, in a different incident at the same company, a worker received a dose of radiation considered lethal, but was saved by prompt hospital treatment
- May 28, 1974 - The Atomic Energy Commission reports that 12 "abnormal events" in 1973 released radioactivity "above permissible levels" at nuclear power plants.
- 1975 - The USS Guardfish attempts to dump the depleted resin from its demineralization system (used to remove dissolved radioactive minerals and particles from the primary coolant loops of submarines). The ship is contaminated when wind blew the resin back onto the ship. This accident is fairly common (see 1961).
- March 22, 1975 - A fire at the Brown's Ferry nuclear reactor located in Decatur, Alabama causes a dangerous lowering of cooling water levels.
- October-November 1975 Apra Harbor, Guam - While disabled, the submarine tender USS Proteus discharged radioactive coolant water. A Geiger counter at two of the harbor's public beaches showed 100 millirems/hour, fifty times the allowable dose.
- January 24, 1978, Soviet nuclear-powered satellite Cosmos 954 crashes in Northwest Territories, Canada. Cleanup efforts recover some material, but much remains unreclaimed.
- May 22, 1978 near Puget Sound, Washington - Aboard the USS Puffer, a valve was mistakenly opened, releasing up to 500 gallons of radioactive water.
- March 28, 1979 - Equipment failures and worker mistakes contribute to a loss of coolant and a partial core meltdown at the Three Mile Island nuclear reactor in Middletown, Pennsylvania. This is the worst commercial nuclear accident in the United States to date.
- July 16, 1979, Church Rock, New Mexico - 34th anniversary of Trinity - the earth/clay dyke of a uranium mill's "temporary" settling/evaporating pond—past its planned and licensed life and filled two feet deeper than design despite evident cracking—fails, draining about 100 million gallons of radioactive liquids and 1100 tons of solid wastes, which settle out up to 70 miles down the Rio Puerco
- September 29, 1979 - Gov. Babbit of Arizona orders the National Guard to clean up American Atomics' Tucson plant, which he believes has been leaking. (Reports of problems by the Arizona Atomic Energy Commission had been stalled by a commissioner, who was also a vice-president of American Atomics.) At the kitchen for the public school system, across the street, $300,000 of food is found contaminated by radioactive tritium; chocolate cake had 56 nCi/L, 2½× "safe" standard. Nuclear official accuses Babbit of "greed for publicity."class="external">[1
- September 19, 1980 - An Air Force repairman doing routine maintenance in a Titan II ICBM silo dropped a wrench socket, which rolled off a work platform and fell to the bottom of the silo. The socket struck the missile causing a leak from a pressurized fuel tank. The missile complex and surrounding area was evacuated. Eight and a half hours later, vapors within the silo ignited and exploded. The explosion fatally injured an Air Force specialist. Twenty-one other USAF personnel were injured.
- February 11, 1981 - A new worker inadvertently opens a valve more than 110,000 gallons of radioactive coolant liquid leaks into the containment building of the Tennessee Valley Authority Sequoyah 1 nuclear power plant in rural Tennessee. Eight workers are contaminated with radiation.
- November 2, 1981, U.S. Submarine Pens, Scotland - A fully-armed Poseidon missile was accidentally dropped 17 feet from a crane while being transferred from a submarine to its tender.
- April 25, 1981 - More than 100 workers are exposed to radiation during repairs of a nuclear power plant in Tsuruga, Japan.
- June, 1981, Salem 2 reactor, Salem, New Jersey - A 3,000 gallon leak of radioactive water.
- 1982 International Nutronics, of Dover, New Jersey - completely contaminates its plant, forcing its closure. IN used radiation to treat gems for color, modify chemicals, and sterilize food and medical supplies. A pump siphoned water from the baths to the floor. The water entered the sewer system of Dover. The NRC was informed of the accident ten months later, by a whistleblower.
- January 25, 1982 Rochester Gas & Electric Company's Ginna plant, Rochester, New York. A steam generator pipe breaks, spilling fifteen thousand gallons of radioactive coolant on the plant floor. Small amounts of radioactive steam escape into the air.
- February, 1982, Nuclear power plant, Salem, New Jersey - A 3,000 gallon leak of mildly radioactive water contaminates 16 workers.
- January 15-16, 1983 Nuclear power plant, Brown's Ferry, Tennessee - 207,000 gallons of low-level radioactive water is accidentally dumped into the Tennessee River.
- February 25, 1983 Nuclear power plant, Salem, New Jersey - The Salem 1 reactor fails to shut down automatically, but the operator detects the problem 90 seconds before an "incident" can occur. Automatic systems had failed to respond three days earlier. Salem 1 also experienced radioactive gas leaks in March 1981 and September 1982.
- August 1983, 3,700 liters of tritium leaked into Lake Huron and Lake Ontario from Canadian nuclear power stations.
- 1986, Hanford Engineering Works, Hanford, Washington - The U.S. Government declassified 19,000 pages of documents indicating that between 1946 and 1986 the Hanford Engineering Works released billions of gallons of radioactive liquids and billions of cubic meters of gases containing plutonium and other isotopes. Detrimental effects were noted as early as 1948, but reports critical of the facilities remained classified. Of 270,000 people living in the affected area, most received low doses of radiation from Iodine. About 13,500 received a dose 1,300 times the amount considered safe for civilians. Approximately 1,200 children received doses far in excess of this number.
- 1986, International Nutronics of Dover, New Jersey and one of its top executives are convicted by a federal jury of conspiracy and fraud. Radiation remains in the vicinity of the plant, but the NRC says the levels aren't hazardous.
- January 6, 1986 The Kerr-McGee nuclear fuel reprocessing plant in Gore, Oklahoma - a cylinder of nuclear material burst after being improperly heated. One worker dies, 100 are hospitalized.
- 1986 The NRC revokes the license of a Radiation Technology, Inc. (RTI) plant in New Jersey for worker safety violations. A safety device to prevent people from entering the irradiation chamber during operation was bypassed. A worker received a near-lethal dose of radiation. RTI was cited 32 times. Violations also included throwing radioactive garbage out with the regular trash.
- April 26, 1986 - The worst accident in the history of nuclear power occurred at the Chernobyl nuclear power plant located near Kiev, USSR (now part of the Ukraine). Fire and explosions resulting from an unauthorized experiment leave 31 dead in the immediate aftermath. Radioactive nuclear material is spread over much of Europe. Over 135,000 were evacuated from the areas around Chernobyl. Many of these areas remained uninhabitable for many years later.
- 1987 - Scavengers break open a radiation-therapy machine in an abandoned clinic of Goiania, Brazil. They sell the kilocurie cesium-137 source as a glowing curiosity. 400 are contaminated, four die.
- 1988, Savannah River, Georgia - The National Research Council panel released a report listing 30 "significant unreported incidents" at the Savannah River production plants over the previous 30 years. Ground water contamination occurred.
- June 6, 1988, Radiation Sterilizers, Decatur, Georgia - Reported a leak of Cesium-137 at their facility. Seventy thousand medical supply containers and milk cartons were recalled. Ten employees were exposed. Three "had enough on them that they contaminated other surfaces" including their homes and cars. (according to Jim Setser at the Georgia Department of Natural Resources.)
- October 1988, Nuclear trigger assembly facility, Rocky Flats, Colorado - Two employees and a Department of Energy inspector inhaled radioactive particles, causing closure of the plant. Several safety violations were cited, including uncalibrated monitors, inadequate fire equipment, and groundwater contaminated with radioactivity.
- January, 1989, Savannah River, Georgia - A fault was discovered to run under the Savannah river nuclear processing plants, to an underground aquifer providing drinking water to much of the southeast. Nearby turtles had radioactive strontium of up to 1,000 times the background level.
- November 24, 1989 - near meltdown at Greifswald, East Germany 
- January 23, 1990, Bruce A, Ontario, Canada - 12,000 litres of heavy water are accidentially dumped into the containment vault below the reactor when a software failure releases the brakes on a refueling machine.
- November 24, 1992, Fuel Reprocessing Plant, Gore, Oklahoma - The plant closed after repeated safety and environmental violations. Its record during 22 years of operation included a 1986 accident that killed one worker and injured dozens of others, contamination of the Arkansas River and groundwater. It had been shut down the previous week by the Nuclear Regulatory Commission when an accident released toxic gas, causing thirty-four to seek medical attention. The plant had been shut down in 1991 when the water of a nearby construction pit had high concentrations of uranium. The government cited Carol Couch, the plant's environmental manager, for obstructing the investigation and falsifying documentation.
- February 15, 1993, 18,000 litres of heavy water are spilled at the Darlington nuclear power plant in Canada.
- 1997 - Georgian soldiers suffer radiation poisoning and burns eventually traced back to training sources abandoned, forgotten, and unlabelled at the collapse of the Soviet Union. One was a cesium-137 pellet in a pocket of a shared jacket which put out about 130 000× background at 1 m distance.
- May 1997, Hanford Engineering Works, Hanford, Washington - A 40 gallon tank of toxic chemicals exploded, causing a release of about 25,000 gallons of plutonium-contaminated water. Fluor Daniel Hanford Inc., was cited for violations of the Department of Energy's nuclear safety rules and fined $140,625. Violations included the contractor's failure to assure that breathing devices operated effectively, failure to make timely notifications of the emergency, and failure to conduct proper radiological surveys of workers, failure to assure adherence to "criticality" safety procedures. These procedures prevent the waste from acting like a reactor and generating more heat and radioactivity.
- 1998 - Recycler Acerinox in Cadiz, Spain unwittingly melts scrap containing radioactive sources; the radioactive cloud drifts all the way to Switzerland before being detected.
- August 8, 1999, Department of Energy's Gaseous Diffusion Isotope Separation Plant, Paducah, Kentucky - The Washington Post reported that thousands of workers were unwittingly exposed to plutonium and other highly radioactive metals over a 23-year period. Workers were told they were handling uranium rather than the more toxic plutonium. They inhaled radioactive dust as part of a government experiment to recycle used nuclear reactor fuel.
- September 30, 1999 - Japan's worst nuclear accident ever took place at a uranium reprocessing facility in Tokaimura, Ibaraki prefecture, northeast of Tokyo, Japan. The direct cause of the accident was workers putting uranyl nitrate solution containing about 16.6 kg of uranium, which exceeded the critical mass, into the precipitation tank, which was not designed to dissolve this type of solution and was not configured to prevent eventual criticality. This exposed workers and residents in the surrounding area to extremely high levels of radiation.
- February 15, 2000 - The Indian Point II nuclear power plant in New York vented a small amount of radioactive steam when a steam generator failed.
- June 2000, Portsmouth Gaseous Diffusion Isotope Separation Plant, Piketon, Ohio - U.S. Senator Mike DeWine (R-OH) led a field senate hearing to discover evidence about on and off-site contamination. Testimony indicated that the Piketon plant altered workers' radiation dose readings and worked with medical professionals to fight worker's compensation claims.
- July 2000, Hanford Engineering Works, Hanford, Washington - Wildfires hit the highly radioactive "B/C" waste disposal trenches. Airborne plutonium levels were raised in the nearby cities of Pasco and Richland to 1,000 times above normal.
- August 2000, Barents Sea. The Russian submarine Kursk sank after an apparent internal torpedo accident, killing 118. Russia recovered the submarine's nuclear reactor, and stated it had carried no nuclear weapons. Greenpeace, urging Russia to recover the reactor, states there are now ten nuclear reactors and over fifty nuclear warheads on the floors of the world's oceans.
- The (supposedly successful) Japanese program to develop nuclear weapons in World War II. The story is that a prototype was exploded in the China Sea, but the factory in Japanese Korea was not yet on-line when the U.S. began nuclear bombing of Japan. If so, there will be lots of radioactive waste.
- Reports of glow slaves (intentionally irradiated unwilling nuclear laborers) in the U.S.S.R., China, India, Pakistan, N. Korea, and pre-world-war-II Japanese Korea.
- British tests of enhanced-fallout nuclear weapons in Australia.
- South African and Israeli nuclear programs, and radioactive emissions.
- At-sea decommissionings (simple scuttlings) of naval nuclear reactors by the Soviet, British and French Navies.
- Undocumented radiation releases in the U.S.S.R., France, India, China, Japan and Pakistan.