Chernobyl's Elephant's Foot: A stark reminder of a nuclear disaster

One of the remains left behind from the Chernobyl accident was a highly radioactive lava-like material. What was it, and how was it formed?
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Artur Korneyev at the Elephant’s Foot in Chernobyl
Artur Korneyev at the Elephant’s Foot in Chernobyl

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On April 26, 1986, a catastrophic nuclear accident occurred at the Chernobyl nuclear power plant in Ukraine. An explosion at the plant's reactor no. 4, caused by a series of human errors and technical malfunctions, released massive amounts of radioactive material into the environment. The disaster had a devastating impact on the surrounding area, and its effects are still being felt today.

One of the remains left behind from the accident is a highly radioactive lava-like material nicknamed the Elephant’s Foot. It is an enormous mass of a rare substance called corium, approximately 10 feet (3 meters) in length. Just a few minutes of exposure to it is enough to kill a person due to its high radiation levels.

Chernobyl's Elephant's Foot: A stark reminder of a nuclear disaster
Chernobyl nuclear power plant

Discovery of the Elephant’s Foot

A few months after the explosion, a team of engineers was sent to investigate the remains of the reactor. They discovered an enormous mass located in the basement of the plant. They immediately named it the Elephant’s Foot due to its resemblance to the foot of an elephant.

The team proceeded to take a series of photographs and collect samples of the structure. The samples were used to determine the high levels of radiation being emitted by the mass. An important part of the investigation into the Chernobyl disaster was the discovery of the Elephant's Foot. It helped scientists to understand the full extent of the damage caused by the explosion.

Formation and composition of the Elephant’s Foot

After the explosion, the radioactive material from the reactor traveled nearly 6.5 feet (2 meters) into the bottom of the reactor vessel and dropped to the floor of the containment area. Here, it reacted with the concrete of the containment area, changing composition. Eventually, it cooled down and solidified to form the Elephant’s Foot. It is estimated to have reached a temperature of over 4,712 degrees Fahrenheit (2,600 Celsius) during the disaster.

The Elephant’s Foot is a large mass of highly radioactive and molten material known as corium. It is made of a mixture of highly radioactive materials, including uranium, plutonium, and other fission products. It is also composed of concrete, sand, and other materials that were present in the reactor’s core and concrete containment area at the time of the explosion. 

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Corium is only formed naturally during a nuclear accident and has only been formed five times – once at Chernobyl, once at the Three Mile Island accident in 1979, and three times at the Fukushima Daiichi reactor disaster in 2011.

The exact composition of the Elephant’s Foot at Chernobyl is unknown due to its highly radioactive nature. However, the brownish color of the Elephant's Foot suggests that it contains a large amount of silica.

The aftermath

Between May and November 1986, a shelter was constructed to help seal the radioactive materials inside reactor no. 4. Referred to as the sarcophagus; the shelter was constructed out of steel and concrete. The sarcophagus contained up to 95% of the original radioactive material within the shelter.

In 1996, ten years after the Chernobyl disaster, Artur Korneyev, a radiation specialist, visited the site. His job was to locate the fuel within the structure to better understand the radiation levels emitted by the Elephant’s Foot. During his visit, he took several photographs of the structure.

These photos served as a warning to the rest of the world about the poor condition of the structure. Following this, a group of seven nations financed the New Safe Confinement project to build a sturdier confinement for the remains of reactor no. 4. The structure was completed in 2016 and is part of a much larger project which aims to make the area around the nuclear power plant safe for the next 100 years.

Chernobyl's Elephant's Foot: A stark reminder of a nuclear disaster
The completed New Safe Confinement over the Chernobyl power plant

Chernobyl today

In the aftermath of the Chernobyl disaster, a huge team of firefighters and emergency workers was sent to the site. Their job was to contain the fire and prevent further damage. Tragically, many of these workers were exposed to high levels of radiation, and at least 50 of them died as a result. To memorialize these workers and firefighters, a sculpture was constructed in Chernobyl as a reminder of their brave efforts.

Chernobyl's Elephant's Foot: A stark reminder of a nuclear disaster
Sculpture of the firefighters and workers who worked to ensure the safety of the areas surrounding the power plant immediately after the explosion.

Today, the town and the surrounding area, known as the Chernobyl Exclusion Zone, remain uninhabited due to the high levels of radiation that still linger in the area. Parts of the exclusion zone, an area of roughly 1,550 square miles (4,000 square kilometers), is now a tourist attraction, with visitors able to explore the abandoned town and the power plant. However, it is still considered highly dangerous to spend extended periods of time in the area.

The Elephant's Foot remains an important scientific curiosity despite the risks. It sheds light on the effects of nuclear disasters and the behavior of highly radioactive materials. The Elephant's Foot may help to improve our understanding of the risks associated with nuclear power. We can use this to develop better safety measures to prevent future catastrophes.