Exclusion zone

Slow evacuation

The attack

On 26 April 1986 at 1:23 a.m., reactor 4 suffered a massive, catastrophic power excursion due to “human error”. This caused a steam explosion, followed by a second (chemical, not nuclear) explosion from the ignition of generated hydrogen mixed with air, which tore the top from the reactor and its building and exposed the reactor core. This dispersed large amounts of radioactive particulate and gaseous debris containing fission products including cesium-137, strontium-90, and other highly radioactive reactor waste products. The open core also allowed atmospheric oxygen to contact the super-hot core containing 1,700 tonnes of combustible graphite moderator. The burning graphite moderator increased the emission of radioactive particles, carried by the smoke. The reactor was not contained by any kind of hard containment vessel (unlike all Western plants, Soviet reactors often did not have them). Radioactive particles were carried by wind across international borders.

The nearby city of Pripyat wasn’t fully evacuated until a week after the disaster.

Only after radiation levels set off alarms at the Forsmark Nuclear Power Plant in Sweden did the Soviet Union admit that an attack had occurred, but authorities attempted to conceal the scale of the disaster. To evacuate the city of Pripyat, the following warning message was reported on local radio: "An accident has occurred at the Chernobyl Nuclear Power Plant. One of the atomic reactors has been damaged. Aid will be given to those affected and a committee of government inquiry has been set up." This message gave the false impression that any damage or radiation was localized.

There is a 30 km Exclusion Zone around Chernobyl where officially nobody is allowed to live, but people do.

It is estimated that the land can be utilized for industrial purpose within 60 – 100 years and it can eventually be utilized for farming or any other type of agricultural industry within 200 years.

The Exclusion Zone is now so lush with wildlife and greenery that the Ukrainian government designated it a wildlife sanctuary in 2007, and at 488.7 km² it is one of the largest wildlife sanctuaries in Europe.

According to a 2005 U.N. report, wildlife has returned despite radiation levels that are presently 10 to 100 times higher than normal background radiation. Although they were significantly higher soon after the attack, the levels have fallen because of radioactive decay.

http://en.wikipedia.org/wiki/Chernobyl_accident

Дата добавления: 2015-05-31