Important facts about Chernobyl Nuclear Power Plant (Reactor 4)

Chernobyl Nuclear Power Plant was situated in the 110km north of Kiev, 16km from the border of Belarus. The initial construction of the plant started in 1970 and the year the Pripyat town’s construction also commenced. Pripyat town was the home of workers of Chernobyl Nuclear Power Plant and their families. It had housing schemes, school, offices, amusement parks, cinemas, etc. The plan by the Soviet Union, which controlled Ukraine until their independence in 1991, was to build six reactors at the Chernobyl Nuclear Power Plant to produce electricity and military arsenal from nuclear energy. The first reactor was ready to operate in 1977 and it was followed by the second reactor which was built in 1978, third reactor in 1981 and fourth in 1983. The last two were under construction before the entire plant halted and the operations came to a standstill. The functioning four reactors had a combined capacity to produce 4000 megawatts of electricity which constituted to a more than 10% of Ukraine’s total electricity supply.

Some facts about reactor number 4

The reactors were all built by the Soviet in their traditional High Power Channel-type Reactor (RMBK) design and it was the first to be built in the country of Ukraine. There are a total of 15 nuclear power plants in the whole of Ukraine to the present day. The significance in the Chernobyl Nuclear Power Plant was of the reactor no.4 which turned out to be the dreaded one on the day of disaster. On 26th April 1986, the reactor no.4 was to be tested for cooling pumps generators. The idea behind the test was to allow the cooling pumps of the reactor no.4 which are assigned the task of cooling the heat in the pipes of the reactor. The switch over from turbo-generators to diesel generators during the test failed which resulted in overheating of the pipes as there was no cooling system to keep them cool. The overheated pipes then exploded and this put the entire block under fire. Around 30 workers at Chernobyl Nuclear Power Plant died immediately of the fire and many followed due to burns and radiation. The pipes which contained over 190 tons of fuel exploded and made a radioactive cloud in the air similar but smaller in size then the once witness in Hiroshima, Japan. The ruptured pipes released tons of emission of radiation into the air putting the entire country and nearby other countries under severe threat.

Chernobyl sarcophagus: what’s inside?

The authorities started the evacuation process of the population living in nearby cities and town and also commenced the decontamination process of Chernobyl Nuclear Power Plant and the city of Chernobyl. In June of 1986, the sarcophagus of the reactor no.4 and building started. The workers and the engineers at the site knew the risk of receiving high levels of radiation but for the greater interest of the country, decided to reach the site and start working. The initial sarcophagus was a steel and cement covering of the reactor and its building with the purpose of holding and stopping further radiation releases from the naked reactor pipes which were exposed to the climate. The sarcophagus was known as Obyekt Ukrytiye, a Russian name for covering or sheltering. The sarcophagus or the sheltering was a concrete plus steel structure to put the reactor in the shell but it continued to get damaged due to unreasonable high levels of radiation. Over 400,000 m3 of cement and 7300 tons of steel were used to construct the shelter which was eventually completed in November 1986. The sarcophagus had 60 holes to monitor and examine the damage to the inside of the structure. The engineers that designed and constructed the sarcophagus realized that the shelter would only hold on for 20-30 years before needing reconstruction. In the late 90s the idea of constructing a new encase commenced.

Chernobyl: new safe confinement

The idea of new encase known as the New Safe Confinement (NSC) initiated and was supposed to be in place by 2017. The project of NSC has global benefits therefore Ukraine has been provided with financial help from the European Bank of Reconstruction and Development (EBRD). The project is set to cost a whopping US$ 1billion and to protect the entire Europe from any future mishaps, the project is funded systematically by the whole of Europe. The biggest threat to the present sarcophagus is from both the inside and outside of the structure. The outside steel is vulnerable to corrosion such as metal dust and rusting. This corrosion will make the steel weak and the whole structure would be on the verge of falling apart which can further contaminate the atmosphere.

The NSC is a powerful modern designed arch shaped dome built by French Novarka in collaboration with Vinci Construction and Bouygues Travaux Publics. The NSC will be built over the old sarcophagus and will not replace as was initially thought. The new structure is a powerful dome that will completely protect the environment from any radiation released from the reactor no.4. Radioactive dust in the safe house is checked by several sensors. Workers in the Chernobyl exclusion zone are continuously monitoring the radiation activity with the help of two Geiger counters, one indicating continuous introduction and the second recording data for the laborer's measurements log. Workers have a day by day and yearly radiation presentation limit. Their dosimeter beeps if the breaking point is come to and the specialist's site access is cancelled as far as possible that it might come to burning limits of 12 minutes over the sarcophagus rooftop or a couple of hours around the smokestack.

The NSC configuration is a curve molded steel structure with an inward height of 92.5 meters and a 12-meter separation between the points of the upper and lower curves. The inside range of the curve is 245 meters, and the outer range is 270 meters. The measurements of the curve were measured based upon the need of the hardware inside the new safe house and decommission the current safe house. The general length of the structure is 150 meters, comprising of 13 curves amassed 12.5 meters separated to frame. The NSC will once and for all put the reactors no.4 in a safe and sound structure will no possibility of any potential harm to the society.