The sarcophagus of unit 4
In 1986, the Soviet authorities dumped, by helicopters, thousands of tons of materials on the damaged unit No. 4. Then they built in a few months a building called the "sarcophagus" . The sarcophagus contains the bulk of 190 tons of fuel remained in the melted core of the reactor. Built in emergency and fragile, the sarcophagus aim was to reduce the risk of collapse and of further leakage of radioactive material.
Petr Pavlicek / IAEA