2. Chernobyl: Russian nuclear power plant explosion

On April 26, 1986 tests were conducted in nuclear reactor 4 of the Chernobyl nuclear power plant in Ukraine, located 80 miles from Kiev. These tests required part of the security system to be shut down. Errors in the reactor design and errors in judgment of the personnel of the power plant caused cooling water to start boiling. This caused reactor stress, resulting in energy production increases to ten times the normal level. Temperatures reached more than 2000 °C, causing fuel rod melting and further cooling water boiling.
Extreme pressures in cooling water pipes resulted in cracks, which caused steam to escape. At 1:23h in the middle of the night the escaped steam caused an explosion slamming off the roof of the building, starting a major fire and simultaneously forming an atmospheric cloud containing approximately 185 to 250 million curies of radioactive material.

Fire and explosion instantly killed 31 people. Two days after the explosion, the Swedish national radio reported that 10.000 times the normal amount of cesium-137 existed in the atmosphere, prompting Moscow to officially respond. The following day over 135.000 people were evacuated from within an 30 km radius of the accident. This area was labelled the 'special zone'. The evacuation of the special zone was permanent, as the high levels of radioactivity have been predicted to exist for several centuries.
The radioactive cloud was blown north and northwest by wind, causing the first mention of the accident to be after radioactivity measurements in Sweden. The cloud covered a large area in Europe. On May 2, the cloud even reached the Netherlands, causing fresh fruit and vegetable consumption to be prohibited.

There are many estimates concerning the number of victims that suffer from symptoms induced by radiation. Reliable data is still lacking. The World Health Organization (WHO) stated that approximately 800.000 people have worked on fire extinguishing, restoring the reactor and cleaning up pollution in the first year after the accident. These people only remained in the area for short periods of time to prevent health problems. Ukrainian government figures show that more than 8.000 Ukrainians have died as a result of exposure to radiation during the first cleanup operation. It is stated that the eventual death toll resulting from the nuclear explosion ranges from 30 to 300.000 and many unofficial sources put the toll over 400.000.

The people that have lived in the Chernobyl area during the accident suffer from various health problems. Immediately following the accident, hundreds of people were diagnosed with radiation sickness. Particularly in Belarus, there has been a dramatic increase in the number of thyroid cancers (2.400%) and leukaemia (100%).
Children of Chernobyl victims suffer from birth defects (250% increase), causing cancer and heart diseases. Approximately 64% of all Ukrainian children under 15 suffering from cancer lived in the most contaminated areas. Genetic defects often result in mutations causing missing limbs (see picture).

The extraordinary increase in the number of these illnesses can be associated with the exposure of the population to the aggressive radioactive particles released by the Chernobyl explosion. Four dangerous substances were released, which are not identified as such by our bodies:
- Plutonium is recognized as iron by the body and distributed by the blood system. It causes cancers and blood disorders. It has a half-life of 24.400 years and will be present in a 30 km radius around the Chernobyl site for many centuries to come
- Cesium 137 is mistaken for potassium and in absorbed by the muscles
- Iodine 131 is not recognized as a radioactive substance and is therefore absorbed by the thyroid gland. It causes thyroid cancer, particularly in children between 0 and 18 years old. An operation can save the children, but a scar known as the 'Belarussian Necklace' marks them as Chernobyl victims forever
- Strontium 90 is recognized by the body as calcium and causes leukaemia upon distribution throughout the bone structure

Governments in the region estimate that up to seven million people were affected by the accident. Four years after the accident, 627.000 Soviets were already under permanent observation for symptoms and effects of radiation poisoning. The number of individuals that will ultimately be affected by the Chernobyl disaster has been estimated as high as 11 times that of the cancer deaths expected from the combined 1945 bombings of Hiroshima and Nagasaki. Today it is believed that over 4 million people in the Ukraine, Belarus and western Russia still live on contaminated ground.
All Chernobyl-related health effects and the fear of death from radiation have resulted in mental defects in many children. Suicide rates have increased 1.000% in the area.

After the explosion reactor 4 was wrapped in a concrete sarcophagus (see picture) in November 1986 to protect the area. After some time the other three reactors where running again. In 1989 the construction of a 5th and 6th reactor was abandoned. There was some discussion going on about the safety of the sarcophagus of reactor 4. On the long run this would not be a very solid construction and according to many it must be replaced. We now know that this replacement must be carried out soon, because the reactor has begun to leak radiation. Holes and fissures in the structure now cover 1.000 square metres. These cracks and holes are futher exacerbated by the intense heat inside the reactor, which is still over 200 degrees Celsius.
The replacement of the sarcophagus is a very costly operation and is therefore still under discussion. It is also very uncertain if there is even a construction method that would guarantee permanent protection from the large bulk of radiation still present in the remains of reactor 4.

After the Chernobyl disaster international organizations pressured the Ukrainian government to close the remaining reactors. This was disadvantageous for the country, because it derived 5% of its power supply from the power plant. Eventually, it was decided that the power plant would be closed in winter of the year 2000. The Ukrainian government tried to obtain a postponement, but the reactor was nevertheless closed in December 2000.

Dangerous chemicals emitted by the nuclear power plant after the explosion continue to spread by bush fires and weather conditions, re-contaminating soil, air and water. New radiation hot spots are still being discovered today in Belarus and Ukraine and evacuations will need to continue well into the 21st century. Plans have now been made to build a 20.000 ton steel shell to replace the failed sarcophagus around reactor 4. If construction is successful, this will be ready by 2007.

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