Chernobyl Disaster is the worst nuclear disaster the world has seen. It is considered by most as the example of threats nuclear energy poses. In the early morning of April 26, 1986, it took place. It is a fact that the Soviet Union invested a lot in Nuclear Energy. After World War II they build numerous reactors. One such reactor in Chernobyl exploded and burned. This result in releasing a large amount of radioactive material in the air. Today even after the years of the disaster its hazardous effect could be easily seen. The entire area surrounding the reactor is unhabitable for any life form. This disaster has created a long term health impact which cant be nullified. The reason for such an incident, the health concern, and preventive measures are worthy to be known. Here are some facts and stats about this disaster.
Where is Chernobyl situated?
It is situated about 130 kilometers from the city of Kyiv, Ukraine. It is about 20 kilometers from the border with Belarus. There were a total of four nuclear reactors in the power plant. It was built during the 1970s and 1980s. The river Pripyat flows closely with the nuclear site. Most of the water was used as a coolant in the reactor. A city was also built near the river and named as Pripyat. The main aim to build a city less than 3 kilometers from the site was to use it as a workers city. It has a population of about 50,000 people in the year 1986. The oldest town in the region was Chernobyl itself. It has a population of 12,000 at the time of disaster. The major area near the site was forest and farms.
Pripyat town in Chernobyl
The Nuclear Reactors
Chernobyl Nuclear Reactors were Soviet-designed. It used four RBMK-1000 type of reactors. The design and working principle of those reactors are today considered as the root cause of the disaster. RBMK reactors used pressure tube design. The fuel used was an enriched U-235 dioxide. It was used to heat water and form steam. Further, the steam was used to run turbines in the reactors. In most modern-day reactors we use water as a coolant. But this reactor used graphite to moderate reactivity. This fact proves that it was the initial design failure. Thus this fact results in a continuous loop of reaction in the core. The core keeps on getting more reactive and started forming a positive loop. This loop is known as ‘positive void coefficient’.
Positive Void Coefficient resulted in Disaster
Chernobyl nuclear power plant was using RBMK reactors. These ‘Reaktor Bolshoy Moshchnosti Kanalynn’ or RBMK reactors run on void coefficients. Without diving deep in technicality let us understand the void coefficient. It is the measure of the change in reactivity caused by the presence of void in the coolant. A void is typically a steam bubble. When we have a positive coefficient the reactivity is more. Whereas in the case of negative there is less reactivity. This is the result of how much coolant we are using. If water is flowing at a high rate the void formed are removed quickly. But if the speed of coolant is less void remains for a long time. Though positive coefficient awards us with more reactivity. It also exposes us to the danger of explosion. In Chernobyl, the positive void coefficient was tremendously high around 4.7.
30 People Died Instantly of Direct Exposure.
The disaster took place at about 1:23 am on April 26, 1986. The chain reaction in Unit 4 of RBMK reactors got out of control. The production reached a tremendous amount of 200 megawatts. This extensive heat generation became impossible to control. It resulted in a powerful explosion. The explosion was so intense and powerful that it detached a 1000 ton iron and steel lid covering the reactor. This resulted in the discharge of radioactive matter in the atmosphere. After some time the second explosion took place. It completely destroyed the building. Two-person died because of the explosion instantly. Within a month of the incident, 28 others died because of direct exposure to radiation. The deaths were mostly because of ARS which is Acute Radiation Syndrome.
The Soviet Union went miles to cover the disaster
When the worst nuclear disaster happened the Soviet Union thought it would be an easy cover-up. Even the locals were kept uninformed about the gravity of the situation. They did not alert any neighboring countries about the incident. When the Swedish air monitors encountered the very high amount of radioactive particle they begin their investigation. The concluded that the radiations were coming from Chernobyl. This fact forced the Soviet Union to accept the disaster. But in order to save its reputation, they issued a statement saying everything is under control. On the 6th of May, the government accepted the monstrous situation and ordered to close schools in the capital of Ukraine. This resulted in a terrifying situation all across Europe.
Chernobyl Power plant kept running after the Disaster
As the unit 4 of the power plant was blown away in the explosion. As a result, all other units were closed. After a year and a half, all the three remaining units became operational. It is a fact that this particular instance shows the behavior of authorities in this matter. The reopening was widely criticized. People were not sure about the controversial design. Exposure to radioactive particles was also a matter of concern. In 1991 another fire led to the closure of unit two. When the Soviet Union was divided another unit was closed. Ukraine agreed to terminate the final running unit in the year 2000. Thus stats suggest us that even after such disaster the plant remain operational for 14 years.
Thousands of people died because of Cancer
The long-lasting effects of Radioactive particles resulted in many deaths. After the five years of Disaster, the chance of cancer increased by 90%. As a result of this contamination, many measures were taken. By the time of 25 years, more than 5000 cases were registered. The exact number of people who suffered due to this disaster is unknown. Many international foundations have released their own reports. WHO claims more than 5000 people died. UN claims 4000 people died. Thus the fact is we are still unknown with the exact numbers. It is expected that the actual death toll is very high than these numbers.
Chernobyl Destroyed the entire area
The radioactive particles released in the atmosphere destroyed the entire surrounding area. Over 1,25,000 sq km of land was contaminated. Out of this land, 52,000 sq km was agricultural land. The other part was rich in Forests and water bodies. A large area of Pine forest was entirely contaminated. This forest was named as ‘Red Forest’ because of dead trees present in red color. More than 10 cm of soil was replaced in the entire area. The wildlife was affected the most because of this disaster. More than 350 animals were born with different deformities. Many of them were missing certain organs like eyes or ribs. Birds were also affected by this disaster. Chernobyl disaster is a level 7 disaster event. Many reports suggest that it cost an estimated 18 billion rubles to control and prevent this disaster.
