4 suffered a catastrophic explosion and meltdown; as a result of this, the power plant is now within a large restricted area known as the Chernobyl Exclusion Zone.

[6] In 1991, unit 2 was placed into a permanent shutdown state by the plant's operator due to complications resulting from a turbine fire.

[7] Although the reactors have all ceased generation, Chernobyl maintains a large workforce as the ongoing decommissioning process requires constant management.

[8] From 24 February to 31 March 2022, Russian troops occupied the plant as part of their invasion of Ukraine.

Second-generation RBMK designs were fitted with a more secure containment structure, visible in photos of the facility.

[16] The 7A, 7B, and 8B boards are also connected to the three essential power lines (for the coolant pumps), each also having its own diesel generator.

[17][failed verification] The turbo generator is 39 m (128 ft) long and its total weight is 1,200 t (1,300 short tons).

The newer turbines, however, turned out to be more sensitive to their operating parameters, and their bearings had frequent problems with vibrations.

Ukraine agreed to close the remaining units in exchange for EU assistance in modernizing the shelter over reactor No.

4 and improving the energy sector of the country, including the completion of two new nuclear reactors, Khmelnytskyi 2 and Rivne 4.

[20] SKALA (Russian: СКАЛА, система контроля аппарата Ленинградской Атомной; sistema kontrolya apparata Leningradskoj Atomnoj, "Control system of the device of the Leningrad Nuclear [Power Plant]", lit.

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.

The accident was not made public until several years later, despite cleanups taking place in and around the power station and Pripyat.

The room which housed the steam separators would reach temperatures as high as 270 degrees Celsius.

The destroyed reactor was encased in a concrete and lead sarcophagus, followed more recently by a large steel confinement shelter to prevent further escape of radioactivity.

2 was permanently shut down shortly after October 1991 when a fire broke out due to a faulty switch in a turbine.

A faulty switch caused a surge of current to the generator, igniting insulating material on some electrical wiring.

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.

[9][33] The resulting activity reportedly led to a 20-fold increase of detected radiation levels in the area due to disturbance of contaminated soil.

However, Ukrainian authorities reported that there was a risk of a radiation leak due to spent fuel coolant being unable to circulate properly.

[37] 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.

[8] The IAEA later clarified that only modest radiation doses (6.5 mSv/year) could have resulted from such activities, and a tour guide in the Zone later acknowledged to the Washington Post that he had helped start these rumors in a "huge exaggeration."

On 14 February 2025, Ukrainian president Volodymyr Zelenskyy said that a Russian drone attack significantly damaged the Chernobyl New Safe Confinement, which covers the sarcophagus and Unit No.

[40] The Chernobyl New Safe Confinement is equipped with two overhead main cranes, which will be used to remove unstable parts of the original sarcophagus.

[41][42] The majority of the external gamma radiation emissions at the site are from the isotope caesium-137, which has a half-life of 30.17 years.

Discussions about the future of nuclear energy in Ukraine ultimately moved the government toward a decision to decommission reactor No.

3 was shut down after operating briefly since March 1999 following almost three months of repairs,[45][46] and the plant as a whole ceased producing electricity.

In 2013, the pump lifting river water into the cooling reservoir adjacent to the facility was powered down, with the thermal sink expected to slowly evaporate.

[50] The New Safe Confinement was financed by an international fund managed by the European Bank for Reconstruction and Development and was designed and built by the French-led consortium Novarka.

[56] A separate deal has been made with the American firm Holtec International to build a storage facility within the exclusion zone for nuclear waste produced by Chernobyl.