Chernobyl Nuclear Power Plant
The V.I. Lenin Memorial Chernobyl Nuclear Power Station (Russian: Чернобыльская АЭС им. В.И.Ленина, Ukrainian: Державне
спецiалiзоване пiдприємство "Чорнобильська АЕС") is a Nuclear
Construction
The station consisted of four reactors of type RBMK-1000, each capable of producing 1000 megawatts of electric power (3.2 GW of thermal power).
Construction of the plant and the city of Pripyat to house workers and their families began in 1970, with reactor no. 1 commissioned in 1977. It was the third nuclear power station in the USSR of RBMK type (after Leningrad and Kursk), and the first ever nuclear power plant on Ukrainian soil. The completion of the first reactor in 1977 followed by reactor no. 2 (1978), no. 3 (1981), and no. 4 (1983). Two more reactors, nos. 5 and 6, capable of producing 1000 MW each, were under construction at the time of the accident. Reactor no. 5 was almost complete at the time of the accident and was scheduled to start operating in the fall of 1986. However, it has since been abandoned; construction cranes still stand next to it to this day.
Accidents
1982
In 1982, a partial core meltdown occurred in the reactor no. 1 at the Chernobyl plant. Due to the secret policy of the Soviet Union, the extent of the accident was not made public until years later. The reactor was repaired and put back into operation within months.
1986
On April 26, 1986, a disaster occurred at reactor no. 4, which has been widely regarded as the worst accident in the history of nuclear power. As a result, reactor no. 4 was completely destroyed and has since been enclosed in a concrete sarcophagus to prevent further escape of radiation. Population of nearby areas were evacuated. Large areas within Europe became contaminated with radiation and different kinds of cancer have been on the rise in Ukraine and neighboring Belarus, which received the greatest amount of fallout. The construction of a new reactor no. 4 sarcophagus is underway.
1991
In 1991, during a scheduled shutdown, a fire broke out in one of the turbines belonging to reactor no. 2 which had caused severe damage to the reactor building. It was then decided that reactor no. 2 would not be returned to operation because of the severity of the damage.
Decommissioning
Since 1991, Western nations had been pushing Ukraine to shut down the Chernobyl plant. After the fire at reactor 2, it was decided that the plant would be taken out of service in two stages, with one of the two remaining reactors being shut down by the year 1996 and another by the year 2000. It was decided that reactor 1 would be shut down first for two reasons; one being that it is the older of the two and because too much health and money was invested into making reactor 3 operational just four years earlier that it would not make much sense to take it out of service that soon.
Unit 3 was the last reactor to be operated at the Chernobyl plant. To meet the year 2000 deadline, the reactor was shut down on 15 December 2000 in the official ceremony of power plant shut-down with Ukrainian President Kuchma present in the control room during the event.
Even after the last reactor shutdown, people continue to work at the Chernobyl plant until the reactor units 1, 2, and 3 are totally decommissioned, which is expected to take years. The first stage in decommissioning is the removal of highly radioactive spent nuclear fuel, which is placed in deep water cooling ponds. However, facilities for this storage are not suitable for the long term, and those on site do not have the capacity for all the spent fuel from units 1, 2 and 3. A second facility is planned for construction that would use dry storage technology suitable for the long term and have the required capacity.[1]
Removal of uncontaminated equipment has begun at unit 1 and this work could be complete by 2020-2.[2]
The remains of the reactor unit 4 will remain radioactive for some time. The isotope responsible for the majority of the external gamma radiation dose at the site is Cs-137 which has a half life of about 30 years. It is likely that even with no further decontamination work, in 300 years the gamma dose rate at the site will be close to the background level. However some of the alpha emitters are longer lived, the soil and many surfaces in and around the plant are likely to be contaminated with transuranium metals such as plutonium and americium, which have much longer half lives. It is planned that the reactor buildings will be disassembled as soon as it will be radiologically safe to do so.
Sarcophagus Replacement
On September 17, 2007 it was announced that a new steel containment structure would be built to replace the aging and hastily built sarcophagus that currently protects the damaged reactor. The project, financed by an international fund managed by the European Bank for Reconstruction and Development, will be designed and built by the French-led consortium Novarka, which includes the companies Bouygues SA and Vinci SA. Novarka will build a giant arch-shaped structure out of steel, 190 metres wide and 200m long to cover the old crumbling concrete dome that is currently in use.
It is expected to take a year to design the new building and another 2 years to build it. The steel casing project is expected to cost $1.4bn (£700m). A separate deal has also been made with the a US firm called Holtec to build a storage facility within the exclusion zone for nuclear waste which has been produced by Chernobyl.
See also
- Other Chernobyl articles
- Chernobyl2020
- Chernobyl compared to other radioactivity releases
- Chernobyl disaster
- Chernobyl disaster effects
- Chernobyl Heart
- Chernobyl in the popular consciousness
- Zone of alienation – The restricted zone formed around the accident site
- List of Chernobyl-related charities
- List of Chernobyl-related articles
- Other accidents
External links
- Chernobyl Nuclear Power Plant - official website (English)
- Construction of the Chernobyl Nuclear Power Plant - video (Russian)
- Shut down of reactor no. 3 in December of 2000 - video (Russian)
- Slide show of a visit to the Chernobyl reactor in April 2006 by a German TV team joint by Reserch Center Juelich
- Chernobyl Nuclear Power Plant at Google Maps
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