After the explosion of the Chernobyl Nuclear Power Plant a great amount of radioactive substance was thrown out of the wrecked reactor into the atmosphere. The fall-out covered the territory of Belarus in a few big spots. The total area of the territory of Belarus contaminated with radionuclides amounts to 46.5 thousand km2. It is more than 20% of the whole territory. After the Chernobyl accident Belarus has become the zone of the ecological disaster.