Chernobyl NPP

1985

Maintenance of the nuclear reactor RBMK-1000 the 1st power unit of Chernobyl nuclear power plant, Pripyat, 1980s.

1986

Power unit explosion

At 01:23:47 on Saturday, April 26, 1986, an explosion occurred at the 4th power unit of the Chernobyl nuclear power plant, which completely destroyed the reactor. The power unit building partially collapsed, killing two people. A fire started in various rooms and on the roof.

​​Avariya at the Chernobyl nuclear power plant. April 26, 1986, Pripyat.

A large amount of radioactive substances were released into the environment. It was by this that the accident at the Chernobyl nuclear power plant was radically different from the bombing of Hiroshima and Nagasaki, the explosion resembled a very powerful "dirty bomb" - the main damaging factor was radioactive infection.

From what and how the explosion occurred

During a routine inspection on April 26, 1986, the fourth reactor of the Chernobyl nuclear power plant experienced a power jump and a reactor protection and shutdown system was triggered. But the reactor was not shut down. Attempts to contain the surge and a dangerous increase in core temperature led to an even greater increase in power. Manual control rods used to monitor core temperature were inserted too late. When they were introduced into the core, they began to crack and got stuck. The temperature and power continued to rise until all the water used to cool the reactor evaporated, causing a powerful increase in pressure. The first steam explosion in the reactor led to the fact that its cover weighing two thousand tons pierced the roof of the power unit.

The damage proved catastrophic; the remaining cooling water from the destroyed channels rushed into the reactor, and contacting the hot fuel rods, immediately turned into steam. Shortly after the first explosion, another, more powerful explosion occurred, throwing the core material into the air. The fire and the spread of radioactive residues began.

A map showing how a cloud of radiation consumed Europe during the 1986 Chernobyl disaster.

And since the hot heart of the reactor was no longer protected by tons of steel and concrete, the core was no longer cooled. Melting began.

The liquidator is preparing to clean the roof of reactor number four. Chernobyl, 1986.

When we talk about melting the core, it's not just some kind of metaphor. Radioactive materials used as fuels are increasingly heated by the uncontrolled release of large energy particles, and this happens until they literally melt, turning into something resembling lava.

In Chernobyl, the loss of cooling water caused fuel to melt, some of which was released into the atmosphere. But another part of the glass fuel under the reactor into the pool, melting its base. The stream of radioactive lava, flowing through pipes and burning through concrete, gradually cooled and froze. As a result, a cluster of stalactites and stalagmites was formed, covered with hardened lava, as well as a large black mass, which was later called the "elephant leg."

"Elephant Leg"

By the fall of 1986, teams of liquidators fighting the Chernobyl nuclear disaster reached the underground corridor at the base of emergency reactor number four. Inside the so-called bubbler pool, they found black lava that flowed directly from the core. The most famous formation there was solid, and radiation sensors strictly warned liquidators that it was impossible to approach it. They pushed the camera around the corner on a tripod and removed this mass, giving it the grim name "elephant leg."

'Elephant's foot'at Chernobyl nuclear power plant, 1986 Leaked nuclear fuel mixed with concrete and sand

Discovered by liquidators in the basement of the fourth block of the nuclear power plant. She remains deadly today, in a few minutes next to her a person will receive a fatal dose of radiation.]]

According to measurements made at that time, the still hot part of the molten rod emitted such an amount of radiation that a lethal dose could be obtained in 300 seconds.

Elephant Leg may still be the most dangerous escape on the planet.

In 30 seconds, you can get a dose after which a week later you will feel dizzy and tired. Two minutes of radiation and you will soon be bleeding. Four minutes: vomiting, diarrhea, fever. 300 seconds, and you will have two days to live.

Delay in evacuating residents

The evacuation of Pripyat residents began only a day later, and Chernobyl only on May 4.

Chernobyl: after the nuclear disaster, "evacuation is not required," USSR, 1986.

Dealing with the consequences of an accident

Liquidators of the Chernobyl accident on the roof of reactor No. 3, 1986. Photo taken by Igor Kostin. The white stripes at the bottom of the photo were due to high levels of radiation.

Treatment of the victim during the Chernobyl accident. Patient V.I. Starovoit, 27 years old, who participated in extinguishing the fire from the first minutes after the accident, in addition to the general uniform gamma radiation, received radiation burns of up to 34% of the body surface. For a period of temporary but significant decrease in the number of white blood cells and wet burn areas of the skin, he was placed in an isolation room with a sterile air flow, which excludes exogenous infection, subject to personnel aseptic rules. Irradiation was received even by those who treated the irradiated. Photographer: Vladimir Vyatkin. May 1986.

​​Lyudi who saved Europe from disaster. Alexey Ananenko, Valery Bespalov and Boris Baranov are Chernobyl employees who descended under radioactive water and opened the valves, preventing contact of the coolant and the hot core of the reactor

None of the three liquidator heroes died in 1986. Boris Baranov died only 19 years after the accident, having received the title of "Honorary Power Engineer" before that. Valery Bespalov lived in the city of Slavutich and back in 2008 gave an interview to the press. Alexey Ananenko in 2011 was appointed Director for Institutional Development of the Nuclear Association, in 2014 he made a report at an international conference.

BelAZ takes part in the decontamination of the city of Pripyat, USSR, 1986.

The photo shows a rare watering BelAZ. During the decontamination of the city of Pripyat, it was supposed to be used as the most powerful watering machine for washing the tallest sixteen-story residential buildings in Pripyat, but it could not be used for this purpose, since its powerful jet knocked out the glass in the windows.

The robot with remote control STR-1 takes part in cleaning the Chernobyl roof from debris of highly radioactive elements of the destroyed reactor. 1986, Pripyat

Singer Alla Pugacheva signs autographs to the liquidators of the Chernobyl accident, September 9, 1986, p. Zeleny Cape

1989

Residents of Ukraine demand information about the real scale and consequences of the Chernobyl accident, May 31, 1989.

1990: Children of Chernobyl Programme

Fidel Castro meets the first Ukrainian children who arrived in Cuba under the program "Children of Chernobyl," 1990. The program operated for 21 years.

The help of Cuban specialists was provided to ​​boleye 22 thousand sick children, including 457 oncohematologic patients. 4,512 patients were treated for severe chronic pathology in inpatient health facilities. During this period, 355 surgical operations were carried out in Cuba.

Cuba spent more than $350 million on the program, but in 2012 it was curtailed at the initiative of Viktor Yanukovych, after a request from the Cuban side for joint participation in spending.

1993

Parking of equipment contaminated with radiation, which participated in the elimination of the accident at the Chernobyl nuclear power plant, Ukraine, 1993.

Palace of Culture "Energetik" in the city of Pripyat in 1986 and so it became later.

2020: Boston Dynamics robosobak brought to Chernobyl to measure radiation

In October 2020, the Boston Dynamics robot was brought to Chernobyl to measure radiation. This was announced on its Facebook page by the State Specialized Enterprise "Central Enterprise for Radioactive Waste Management" (GSP "TsPORO"), which tested the robot together with specialists from the University of Bristol. Read more here.