1982 reactor #1 partial meltdown On 9 September 1982, a partial
core meltdown occurred in reactor No. 1 due to a faulty cooling valve remaining closed following maintenance. Once the reactor came online, the uranium in the channel 13-44 overheated and ruptured. The extent of the damage was comparatively minor, and no one was killed during the accident. However, due to the negligence of the operators, the accident was not noticed until several hours later, resulting in significant release of radiation in the form of fragments of uranium oxide and several other radioactive isotopes escaping with steam from the reactor via the ventilation stack. This accident was somewhat similar to the 1975 Leningrad unit 1 accident. The accident was not made public until several years later, despite cleanups taking place in and around the power station and Pripyat. The reactor was repaired and put back into operation after eight months with its capacity reduced by 20% to 800MWe.
1984 reactor #3 and #4 incident According to
KGB documents declassified in Ukraine on 26 April 2021, serious incidents occurred in the third and fourth reactors in 1984. According to these documents, the central government in Moscow knew as early as 1983 that the powerplant was "one of the most dangerous nuclear powerplants in the USSR". The reasoning behind this had to do with the building's structural integrity. The room which housed the steam separators would reach temperatures as high as 270 degrees Celsius. This excess heat caused the concrete of the building to shift its position, which made the building unsafe and could potentially result in the collapse of the steam separators, which would cause it to collapse onto the reactor hall, causing a meltdown.
1986 reactor #4 catastrophe (Chernobyl disaster) On 26 April 1986, reactor No. 4 suffered a catastrophic
meltdown during a safety test resulting in a core explosion and open-air fires. This caused large quantities of radioactive materials to be dispersed in the atmosphere and surrounding land. The radioactive cloud spread as far away as Norway. The disaster is regarded as the worst accident in the history of nuclear power. The destroyed reactor was encased in
a concrete and lead sarcophagus in 1986, followed in 2016 by
a large steel confinement shelter to prevent further escape of radioactivity.
1991 reactor #2 turbine fire Reactor No. 2 was permanently shut down shortly after October 1991 when a fire broke out due to a faulty switch in a turbine. On 11 October 1991, a fire broke out in the turbine hall of reactor No. 2. The fire began in reactor No. 2's fourth turbine, while the turbine was being idled for repairs. A faulty switch caused a surge of current to the generator, igniting insulating material on some electrical wiring. This subsequently led to hydrogen, used as a coolant in the synchronous generator, being leaked into the turbine hall "which apparently created the conditions for fire to start in the roof and for one of the trusses supporting the roof to collapse." The adjacent reactor hall and reactor were unaffected, but due to the political climate it was decided to shut down this reactor permanently after this incident.
2017 Petya cyberattack The
2017 Petya cyberattack affected the
radiation monitoring system and took down the power plant's official website, which hosts information about the incident and the area.
Russian invasion of Ukraine The
Chernobyl exclusion zone was the site of fighting between Russian and Ukrainian forces during the
Battle of Chernobyl as part of the
Russian invasion of Ukraine. On 24 February 2022, Russian forces captured the plant. The resulting activity reportedly led to a 20-fold increase of detected radiation levels in the area due to disturbance of contaminated soil. On 9 March 2022, there was a power cut at the plant itself. No radiation leaks were reported at the time. However, Ukrainian authorities reported that there was a risk of a radiation leak due to spent fuel coolant being unable to circulate properly. On 31 March 2022, Russian forces formally handed control of the plant back to its employees, and most occupying forces withdrew.
Ukrainian National Guard personnel were moved to
Belarus as
prisoners of war. On 2 April 2022, Ukrainian media reported that the
flag of Ukraine was raised at the plant. Russian troops dug trenches and other fighting positions on the outskirts of the highly contaminated
Red Forest, which attracted considerable media attention due to unconfirmed reports that soldiers were being treated for radiation sickness in
Belarus. The
IAEA said that radiation levels at the site remained normal. On 29 April 2026, Ukraine's Energy Minister
Denys Shmyhal announced that the United States would provide $100 million towards repairs of the damaged containment dome, with the total estimated cost of repairs at €500 million ($585 million). == Decommissioning ==