the Chernobyl NPP.
The Chernobyl nuclear power plant is located in Ukraine, Ivanovskiy district. Started operation on September 25, 1977. On April 26, 1986, an explosion occurred that completely destroyed the nuclear power plant's reactor.
In the first days after the disaster, the main efforts were aimed at reducing radioactive emissions from the destroyed reactor and preventing even more serious consequences. We have erected the “Shelter” - an insulating structure over the fourth power unit. Later, the Shelter was given the unofficial name "Sarcophagus". During construction, the service life of the structure was predicted to be 20-40 years. After the construction, the sarcophagus was strengthened. Experts assured that the sarcophagus, with proper care, will stand for more than a decade.
On October 11, 1991, with a decrease in the speed of turbine generator No. 4 of the second unit, an accident occurred due to reasons beyond the control of the reactor installation. Unit 1 was shut down on November 30, 1996. Unit 2 was shut down after the 1991 accident. On December 15, 2000 at 13:17 by order of the President of Ukraine, by turning the emergency protection key (AZ-5), the reactor of power unit No. 3 of the Chernobyl NPP was permanently stopped. The station has stopped generating electricity.
https://ru.wikipedia.org/wiki/Чернобыльская_АЭС