Chernobyl Nuclear Power Plant

Chernobyl Nuclear Reactor No. 4 was one four light water graphite moderated reactors at Chernobyl Nuclear Power Plant, near Pripyat. Reactors 1 and 2 were constructed between 1970 and 1977, while Reactors 3 and 4 were completed in 1983. Two more reactors, of the same design, were under construction in 1986. The town of Pripyat was built to house workers of the Chernobyl Power plant, and is estimated to have had a population of 49,000 in 1986.

On 26th April 1986 late night tests on the Chernobyl Nuclear Power Plant reactor were hastily carried out, reportedly by personnel with little regard for health and safety guidelines. This lack of adherence to safety checklists combined with flawed reactor design, lead to a large steam explosion. The resulting fires sent radioactive plumes into the atmosphere, which had widespread fallout over much of the western USSR and Europe. The firefighters that were first on the scene to extinguish the fires, along with the power station personnel, died of acute radiation sickness in the weeks after the disaster. The firefighters were decontaminated at the Pripyat Hospital No. 126, before being transferred to specialist units in Moscow. By December 1986 the reactor of Chernobyl Nuclear Power Plant was being covered by a concrete sarcophagus, to prevent further release of radioactive material.

The concrete sarcophagus was estimated to be able to protect the site for approximately 20-30 years. In 2016, building of the New Safe Confinement (NSC) was completed costing €1.5 billion. This 270m long dome-shaped structure was built on rails 180m away from Reactor Chernobyl Nuclear Power Plant No. 4 and is the largest movable structure built. On 29th November 2016 it completed its several week journey along its rails, and completely covered the damaged reactor. This new containment structure is estimated to protect the reactor for around 100 years.

Read more about the Chernobyl Nuclear Disaster on the BBC Website.