When Reactor 4 at Chernobyl was destroyed in April 1986, the molten core did not simply vanish. It flowed, cooled and set into new forms in the rooms below. One mass, in a corridor beneath the reactor, became known as the Elephant’s Foot after its size and shape.
The Horror
The Elephant’s Foot is a mass of corium, a molten mixture of core materials, steel, serpentinite, concrete and sand. When it cooled it became a black ceramic made mainly of silicon dioxide, with smaller amounts of uranium, calcium, iron, zirconium, aluminium, magnesium and potassium. Uranium makes up roughly 10 per cent of its mass. It lies in cable corridor 217/2 on the third floor of the reactor building, against the corner of two walls and beside a staircase. It was the largest of three masses in its room.
The discovery date is disputed. One account has two dosimetrists finding a highly radioactive source in late June 1986 and leaving a dosimeter behind, unknowingly near it. Another dates the discovery to December 1986, when Vasya Koryagin reached the area and reported a reading of 50 roentgens per hour. His own estimate for the true level was about 20,000, which the source puts nearer 10,000. Valentin Obodzinsky took the first photograph between December 25 and 31.
About eight months after formation, surface radioactivity was around 8,000 to 10,000 roentgens per hour, a level the source says could deliver a 50 per cent lethal dose within about three minutes. A drill mounted on a remote-controlled trolley could not penetrate the mass. Armour-piercing rounds fired from a rifle were needed to break off usable chunks for analysis.
The Legend
The best-known image of the Foot was taken in 1996 by Artur Korneyev, then deputy director of the New Safe Confinement project, with an automatic camera and a flashlight. A popular version says the grain and streaks come from radiation destroying the film. The caption cited by the source attributes the lightning-like streak to camera movement during a slow exposure, so the claim of a photograph destroyed by its subject is unconfirmed. The story that the shots were fired with a Kalashnikov is also uncited in the source.
The Foot is often called the most radioactive object ever made. The source says this is false. Other corium masses at Chernobyl are also highly radioactive, and a spent fuel rod can emit up to ten times more radiation.
The Modern Relic
The mass has not been moved. Radiation at its surface has fallen with time, to about 1,100 roentgens per hour in 1989 and about 700 by 2000. By June 1998 its outer layers had started to turn to dust and the mass was cracking as its radioactive components decayed. By 2021 it was described as having a consistency like sand. The remaining hazard is mainly external gamma radiation from caesium-137, and alpha-emitting uranium is dangerous if inhaled or swallowed.
