Chernobyl disaster

Un article de Vev.

Modèle:Pp-semi-vandalism

The "Chernobyl disaster", or reactor accident at the Chernobyl nuclear power plant is the worst nuclear power plant accident in history and the only instance so far of level 7 on the International Nuclear Event Scale, resulting in a severe nuclear meltdown. On 26 April 1986 at 01:23:40 a.m. reactor number four at the Chernobyl Nuclear Power Plant located in the Soviet Union near Pripyat in Ukraine exploded. Further explosions and the resulting fire sent a plume of highly radioactive fallout into the atmosphere and over an extensive geographical area.

The plume drifted over parts of the western Soviet Union, Eastern Europe, Western Europe, Northern Europe, and eastern North America. Large areas in Ukraine, Belarus, and Russia were badly contaminated, resulting in the evacuation and resettlement of over 336,000 people. According to official post-Soviet data,<ref name="Chernobyl.info"> Geographical location and extent of radioactive contamination

. Swiss Agency for Development and Cooperation  
 

 

. (quoting the "Committee on the Problems of the Consequences of the Catastrophe at the Chernobyl NPP: 15 Years after Chernobyl Disaster", Minsk, 2001, p. 5/6 ff., and the "Chernobyl Interinform Agency, Kiev und", and "Chernobyl Committee: MailTable of official data on the reactor accident") </ref> about 60% of the radioactive fallout landed in Belarus.

The accident raised concerns about the safety of the Soviet nuclear power industry, slowing its expansion for a number of years, while forcing the Soviet government to become less secretive. The now-independent countries of Russia, Ukraine, and Belarus have been burdened with the continuing and substantial decontamination and health care costs of the Chernobyl accident. It is difficult to tally accurately the number of deaths caused by the events at Chernobyl, as the Soviet-era cover-up made it difficult to track down victims. Lists were incomplete, and Soviet authorities later forbade doctors to cite "radiation" on death certificates.<ref> Folks near Chernobyl still cloudy about health

. Retrieved on 23 November, 2007. </ref>

The 2005 report prepared by the Chernobyl Forum, led by the International Atomic Energy Agency (IAEA) and World Health Organization (WHO), attributed 56 direct deaths (47 accident workers, and nine children with thyroid cancer), and estimated that there may be 4,000 extra deaths due to cancer among the approximately 6.6 million most highly exposed.<ref name="iaea"> IAEA Report

. In Focus: Chernobyl

 

. Retrieved on 2006-03-29. </ref>

Although the Chernobyl Exclusion Zone and certain limited areas will remain off limits, the majority of affected areas are now considered safe for settlement and economic activity.<ref>The Chernobyl Forum: 2003-2005. Modèle:PDFlink. IAEA. 2nd revised version. pg. 6</ref>

The Chernobyl nuclear power plant

Main article: Chernobyl Nuclear Power Plant

The Chernobyl station (Modèle:Coor dms) is located near the town of Pripyat, Ukraine, 18 km northwest of the city of Chernobyl, Modèle:Convert/km from the border of Ukraine and Belarus, and about Modèle:Convert/km north of Kiev. The station consisted of four reactors of type RBMK-1000, each capable of producing 1 gigawatt (GW) of electric power, and the four together produced about 10% of Ukraine's electricity at the time of the accident.^{[citation needed]} Construction of the plant began in the 1970s, with reactor no. 1 commissioned in 1977, followed by no. 2 (197Image:Cool.gif, no. 3 (1981), and no. 4 (1983). Two more reactors, no. 5 and 6, capable of producing 1 GW each, were under construction at the time of the accident.

The accident

On April 26, 1986 at 1:23:58 a.m. reactor 4 suffered a catastrophic steam explosion resulting in a nuclear meltdown, a series of additional explosions and a fire. The radiation was not contained and radioactive particles were carried by wind across international borders.

Test plan

During the daytime of April 25 1986, reactor 4 at Modèle:Coor dms was scheduled to be shut down for maintenance. A decision was made to test the ability of the reactor's turbine generator to generate sufficient electricity to power the reactor's safety systems (in particular, the water pumps), in the event of a loss of external electric power. A RBMK-1000 reactor requires water to be continuously circulated through the core, as long as the nuclear fuel is present.

Chernobyl's reactors had a pair of backup diesel generators, but because there was a 40-second delay before they could attain full speed, the reactor was going to be used to spin up the reactor's turbine generator. Once at full speed, the turbine would be disconnected from the reactor and allowed to spin under its own rotational momentum. The aim of the test was to determine whether the turbines in the rundown phase could power the pumps while the generators were starting up. The test was previously successfully carried out on another unit (with all safety provisions active) with negative results — the turbines did not generate sufficient power, but because additional improvements were made to reactor four's turbines, there was a need for another test.

Conditions prior to the accident

As conditions to run this test were prepared during the daytime of April 25, and the reactor electricity output had been gradually reduced to 50%, a regional power station unexpectedly went offline. The Kiev grid controller requested that the further reduction of output be postponed, as electricity was needed to satisfy the evening peak demand. The plant director agreed and postponed the test to comply. The ill-advised safety test was then left to be run by the night shift of the plant, a skeleton crew who would be working Reactor 4 that night and the early part of the next morning. This reactor crew had had little or no experience in nuclear power plants, many had been drafted in from coal powered plants and another had had a little experience with nuclear submarine power plants.<ref>BBC (British Broadcasting Corporation) Documentary entitled "Days That Shook The World"</ref>

At 11:00 p.m., April 25, the grid controller allowed the reactor shut-down to continue. The power output of reactor 4 was to be reduced from its nominal 3.2 GW thermal to 0.7–1.0 GW thermal in order to conduct the test at the prescribed lower level of power.<ref>Modèle:Ru icon The official program of the test.</ref> However, the new crew were unaware of the prior postponement of the reactor slowdown, and followed the original test protocol, which meant that the power level was decreased too rapidly. In this situation, the reactor produced more of the nuclear poison product xenon-135 (the xenon production rate:xenon loss rate ratio initially goes higher during a reactor power down), which dropped the power output to 30 MW thermal (approximately 5% of what was expected). The operators believed that the rapid fall in output was due to a malfunction in one of the automatic power regulators, not because of reactor poisoning. In order to increase the reactivity of the underpowered reactor (caused unknowingly by neutron absorption of excess xenon-135), automatic control rods were pulled out of the reactor beyond what is allowed under safety regulations.

Despite this breach, the reactor's power only increased to 200MW, still less than a third of the minimum required for the experiment. Despite this, the crew's management chose to continue the experiment. As part of the experiment, at 1:05 a.m. on April 26 the water pumps that were to be driven by the turbine generator were turned on; increasing the water flow beyond what is specified by safety regulations. The water flow increased at 1:19 a.m. – since water also absorbs neutrons, this further increase in the water flow necessitated the removal of the manual control rods, producing a very precarious operating situation where coolant and xenon-135 was substituting some of the role of the control rods of the reactor.

Fatal experiment

At 1:23:04 the experiment began. The unstable state of the reactor was not reflected in any way on the control panel, and it did not appear that anyone in the reactor crew was aware of any danger. The steam to the turbines was shut off and, as the momentum of the turbine generator drove the water pumps, the water flow rate decreased, decreasing the absorption of neutrons by the coolant. The turbine was disconnected from the reactor, increasing the level of steam in the reactor core. As the coolant heated, pockets of steam formed voids in the coolant lines. Due to the RBMK reactor-type's large positive void coefficient, the steam bubbles increased the power of the reactor rapidly, and the reactor operation became progressively less stable and more dangerous. As the reaction continued, the excess xenon-135 was burnt up, increasing the number of neutrons available for fission. The prior removal of manual and automatic control rods had no backup, leading to a runaway reaction.

At 1:23:40 the operators pressed the AZ-5 ("Rapid Emergency Defense 5") button that ordered a "SCRAM" – a shutdown of the reactor, fully inserting all control rods, including the manual control rods that had been incautiously withdrawn earlier. It is unclear whether it was done as an emergency measure, or simply as a routine method of shutting down the reactor upon the completion of an experiment (the reactor was scheduled to be shut down for routine maintenance). It is usually suggested that the SCRAM was ordered as a response to the unexpected rapid power increase. On the other hand, Anatoly Dyatlov, deputy chief engineer at the nuclear station at the time of the accident, writes in his book:

Prior to 01:23:40, systems of centralized control … didn't register any parameter changes that could justify the SCRAM. Commission … gathered and analyzed large amount of materials and, as stated in its report, failed to determine the reason why the SCRAM was ordered. There was no need to look for the reason. The reactor was simply being shut down upon the completion of the experiment.<ref>Modèle:Ru icon Anatoly Dyatlov, Chernobyl. How did it happen? Chapter 4.</ref>

The slow speed of the control rod insertion mechanism (18–20 seconds to complete), and the flawed rod design which initially reduces the amount of coolant present, meant that the SCRAM actually increased the reaction rate. At this point an energy spike occurred and some of the fuel rods began to fracture, placing fragments of the fuel rods in line with the control rod columns. The rods became stuck after being inserted only one-third of the way, and were therefore unable to stop the reaction. At this point nothing could be done to stop the disaster. By 1:23:47 the reactor jumped to around 30 GW, ten times the normal operational output. The fuel rods began to melt and the steam pressure rapidly increased, causing a large steam explosion. Generated steam traveled vertically along the rod channels in the reactor, displacing and destroying the reactor lid, rupturing the coolant tubes and then blowing the lid off the reactor.<ref> Modèle:Ru icon Фатахов Алексей Чернобыль как это было - 2</ref> After part of the roof blew off, the inrush of oxygen, combined with the extremely high temperature of the reactor fuel and graphite moderator, started a graphite fire. This fire greatly contributed to the spread of radioactive material and the contamination of outlying areas.<ref>Chernobyl: Assessment of Radiological and Health Impact (Chapter 1). Nuclear Energy Agency. 2002</ref>

Immediate crisis management

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Radiation levels

At the time of the disaster, the plant's staff were not aware of the true radiation levels, which led to severe misassessments of the situation. The radiation levels in the worst-hit areas of the reactor building have been estimated to be 5.6 röntgen per second (R/s), which is equivalent to 20,000 röntgen per hour (R/h). A lethal dose is around 500 röntgen over 5 hours, so in some areas, unprotected workers received fatal doses within several minutes. However, a dosimeter capable of measuring up to 1,000 R/s was inaccessible due to the explosion, and another one failed when turned on. All remaining dosimeters had limits of 0.001 R/s and therefore read "off scale". Thus, the reactor crew could ascertain only that the radiation levels were somewhere above 0.001 R/s (3.6 R/h), while the true levels were 5,600 times higher in some areas.

Because of the fallacious low readings, the reactor crew chief Alexander Akimov assumed that the reactor was intact. The evidence of pieces of graphite and reactor fuel lying around the building was ignored, and the readings of another dosimeter brought in by 4:30 a.m. were dismissed under the assumption that the new dosimeter must have been defective. Akimov stayed with his crew in the reactor building until morning, trying to pump water into the reactor. None of them wore any protective gear. Most of them, including Akimov, died from radiation exposure within three weeks.

Fire containment

Shortly after the accident, firefighters arrived to try to extinguish the fires. The first one to the scene was a Chernobyl Power Station firefighter brigade under the command of Lieutenant Vladimir Pravik, who died on May 9, 1986. They were not told how dangerously radioactive the smoke and the debris were, and may not even have known that the accident was anything more than a regular electrical fire: "We didn't know it was the reactor. No one had told us."<ref>Modèle:Cite visual</ref> The fires on the roof of the station and the area around the building containing Reactor No. 4 were extinguished by 5 a.m., but many firefighters received high doses of radiation. The fire inside Reactor No. 4 continued to burn until the fire was extinguished by helicopters dropping materials like sand, lead, clay and boron onto the burning reactor.

The explosion and fire threw into the air not just the particles of the nuclear fuel but also far more dangerous radioactive elements like caesium-137, iodine-131, strontium-90 and other radionuclides. The residents of the surrounding area observed the radioactive cloud on the night of the explosion.

Evacuation of Pripyat

The government committee formed to investigate the accident, led by Valeri Legasov, arrived at Chernobyl in the evening of 26 April. By that time two people were dead and 52 were hospitalized. During the night of 26 April – April 27 — more than 24 hours after the explosion—the committee, faced with ample evidence of extremely high levels of radiation and a number of cases of radiation exposure, had to acknowledge the destruction of the reactor and order the evacuation of the nearby city of Pripyat.

The evacuation began at 14:00, 27 April. In order to reduce baggage, the residents were told that the evacuation would be temporary, lasting approximately three days. As a result, Pripyat still contains personal belongings. From eyewitness accounts of the firefighters involved before they died (as reported on the CBC television series Witness), one described his experience of the radiation as "tasting like metal", and feeling a sensation similar to that of pins and needles all over his face. (This is similar to the description given by Louis Slotin, a Manhattan Project physicist who died days after a fatal radiation overdose from a criticality accident.)

Thermal explosion risk

The water that had hurriedly been pumped into the reactor building in a futile attempt to extinguish the fire had run down to the space underneath the reactor floor. Thus the smoldering fuel and other material on the reactor floor was starting to burn its way through this floor, mixing with melted concrete that had lined the reactor, and creating a radioactive semi-liquid material comparable to lava. This was made worse by materials being dropped from helicopters, which only increased the temperatures further.

In order to prevent this, soldiers and workers (called "liquidators") were sent in as cleanup staff by the Soviet government. Two of these were sent in wetsuits to open the sluice gates to vent the radioactive water, and thus prevent a thermal explosion.<ref>The Chernobyl nightmare revisited, BBC News Online</ref> They are thought to be engineers Alexei Ananenko (who knew where the valves were) and Valeri Bezpalov, accompanied by a third man, Boris Baranov, who provided them with light from a lamp, though this lamp failed, leaving them to find the valves by feeling their way along a pipe.<ref>The Worst Accident in the World: Chernobyl: The End of the Nuclear Dream, 1986, p178, by Nigel Hawkes et al., ISBN 0330297430</ref>

Debris removal

The worst of the radioactive debris was collected inside what was left of the reactor. The reactor itself was covered with bags containing sand, lead and boric acid thrown off helicopters (some 5,000 metric tonnes during the week following the accident). By December 1986 a large concrete sarcophagus had been erected, to seal off the reactor and its contents.<ref>The Social Impact of the Chernobyl Disaster, 1988, p166, by David R. Marples ISBN 0-333-48198-4</ref>

Many of the vehicles used by the "liquidators" remain parked in a field in the Chernobyl area to this day.<ref>"

   Chernobyl's silent graveyards 
     
 " , BBC News Online , 2006-04-20
 
 . </ref>

Possible causes of the disaster

There are two official theories about the main cause of the accident. The first was published in August 1986 and effectively placed the blame solely on the power plant operators. This is known as the flawed operators theory.

The second theory, proposed by Valeri Legasov and published in 1991, attributed the accident to flaws in the RBMK reactor design, specifically the control rods. This theory is called the flawed design theory.

Both commissions were heavily lobbied by different groups, including the reactor's designers, power plant personnel, and by the Soviet and Ukrainian governments. The IAEA's 1986 analysis attributed the main cause of the accident to the operators' actions. But in January 1993, the IAEA issued a revised analysis, attributing the main cause to the reactor's design.<ref>NEI Source Book: Fourth Edition (NEISB_3.3.A1)</ref>

A variant theory holds that the operators were not informed about problems with the reactor. According to one of them, Anatoliy Dyatlov, the designers knew that the reactor was dangerous in some conditions but intentionally concealed this information. In addition, the plant's management was largely composed of non-RBMK-qualified personnel: the director, V.P. Bryukhanov, had experience and training in a coal-fired power plant. His chief engineer, Nikolai Fomin, also came from a conventional power plant. Dyatlov, deputy chief engineer of reactors 3 and 4, had only "some experience with small nuclear reactors", namely smaller versions of the VVER nuclear reactors that were designed for the Soviet Navy's nuclear submarines.

In particular:

Flawed design theory

• The reactor had a dangerously large positive void coefficient. The void coefficient is a measurement of how the reactor responds to increased steam formation in the water coolant. Most other reactor designs produce less energy as they get hotter, because if the coolant contains steam bubbles, fewer neutrons are slowed down. Faster neutrons are less likely to split uranium atoms, so the reactor produces less power. Chernobyl's RBMK reactor, however, used solid graphite as a neutron moderator to slow down the neutrons, and neutron-absorbing light water to cool the core. Thus neutrons are slowed down even if steam bubbles form in the water. Furthermore, because steam absorbs neutrons much less readily than water, increasing an RBMK reactor's temperature means that more neutrons are able to split uranium atoms, increasing the reactor's power output. This makes the RBMK design very unstable at low power levels, and prone to suddenly produce too much energy if the temperature rises. This was counter-intuitive and unknown to the crew.
• A more significant flaw was in the design of the control rods that are inserted into the reactor to slow down the reaction. In the RBMK reactor design, the control rod end tips were made of graphite and the extenders (the end areas of the control rods above the end tips, measuring Modèle:Formatnum:1-metre ({{formatnum:{{rnd/+|1*1/0.3048|0|Modèle:Rnd/00}}}} ft) in length) were hollow and filled with water, while the rest of the rod – the truly functional part which absorbs the neutrons and thereby halts the reaction – was made of boron carbide. With this design, when the rods are initially inserted into the reactor, the graphite ends displace some coolant. This greatly increases the rate of the fission reaction, since graphite is a more potent neutron moderator (a material that enables a nuclear reaction) and also absorbs far fewer neutrons than the boiling light water. Thus for the first few seconds of control rod activation, reactor power output is increased, rather than reduced as desired. This behavior is counter-intuitive and was not known to the reactor operators.
• The water channels run through the core vertically, meaning that the water's temperature increases as it moves up and thus creates a temperature gradient in the core. This effect is exacerbated if the top portion turns completely to steam, since the topmost part of the core is no longer being properly cooled and reactivity greatly increases. (By contrast, the CANDU reactor's water channels run through the core horizontally, with water flowing in opposite directions among adjacent channels. Hence, the core has a much more even temperature distribution.)
• To reduce costs, and because of its large size, the reactor had been constructed with only partial containment. This allowed the radioactive contaminants to escape into the atmosphere after the steam explosion burst the primary pressure vessel.
• The reactor also had been running for over one year, and was storing fission byproducts; these byproducts pushed the reactor towards disaster.
• As the reactor heated up, design flaws caused the reactor vessel to warp and break up, making further insertion of control rods impossible.

Flawed operators theory

The operators violated plant procedures and were ignorant of the safety requirements needed by the RBMK design. This is partly due to their lack of knowledge of the reactor's design as well as lack of experience and training. Several procedural irregularities also contributed to causing the accident. One was insufficient communication between the safety officers and the operators in charge of the experiment being run that night.

The effects of the disaster

Main article: Chernobyl disaster effects

International spread of radioactivity

The nuclear meltdown provoked a radioactive cloud which floated over Russia, Belarus, Ukraine and Moldova, but also the European part of the Republic of Macedonia, Croatia, Turkey, Bulgaria, Greece, Romania, Lithuania, Estonia , Latvia, Finland, Denmark, Norway, Sweden, Austria, Hungary, the Czech Republic and the Slovak Republic, The Netherlands, Belgium, Slovenia, Poland, Switzerland, Germany, Italy, Ireland, France (including Corsica<ref name="RFI 24"> Modèle:Fr icon "

   Tchernobyl, 20 ans après 
     
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. European Greens and UK scientists Ian Fairlie PhD and David Sumner 
 
 (April 2006)
   

. Retrieved on 2006-04-21.

(page 3) </ref><ref>Modèle:Fr icon    Les leçons de Tchernobyl 
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. Retrieved on 2006-12-16. </ref> The initial evidence that a major exhaust of radioactive material was affecting other countries came not from Soviet sources, but from Sweden, where on April 27 workers at the Forsmark Nuclear Power Plant (approximately Modèle:Convert/km from the Chernobyl site) were found to have radioactive particles on their clothes.<ref>Modèle:Cite book</ref> It was Sweden's search for the source of radioactivity, after they had determined there was no leak at the Swedish plant, which led to the first hint of a serious nuclear problem in the western Soviet Union. The rise of radiation levels had at that time already been measured in Finland, but a civil service strike delayed the response and publication<ref>Modèle:PDFlink</ref>.

Contamination from the Chernobyl accident was not evenly spread across the surrounding countryside, but scattered irregularly depending on weather conditions. Reports from Soviet and Western scientists indicate that Belarus received about 60% of the contamination that fell on the former Soviet Union. However, the 2006 TORCH report stated that half of the volatile particles had landed outside Ukraine, Belarus and Russia. A large area in Russia south of Bryansk was also contaminated, as were parts of northwestern Ukraine.

In Western Europe, measures were taken including seemingly arbitrary regulations pertaining to the legality of importation of certain foods but not others. In France some officials stated that the Chernobyl accident had no adverse effects – this was ridiculed as pretending that the radioactive cloud had stopped at the German and Italian borders.

Radioactive release (source term)

Like many other releases of radioactivity into the environment, the Chernobyl release was controlled by the physical and chemical properties of the radioactive elements in its core. While plutonium is often perceived as particularly dangerous by the general population, its effects are almost eclipsed by those of its fission products. Particularly dangerous are highly radioactive compounds that accumulate in the food chain, such as some isotopes of iodine and strontium. For more information about the release of radioactivity from power reactors, see fission products, nuclear fuel and nuclear fuel and reactor accidents.

A short report on the release of radioisotopes from the site is on the OSTI web site.<ref>Chernobyl source term, atmospheric dispersion, and dose estimation, EnergyCitationsDatabase, November 1 1989</ref> A more detailed report can be downloaded from the OECD web site's public library.<ref>OECD Papers Volume 3 Issue 1, OECD, 2003</ref> At different times after the accident, different isotopes were responsible for the majority of the external dose. The dose, which was calculated, is from external gamma irradiation, for a person standing in the open. The dose to a person in a shelter or the internal dose is harder to estimate.

The release of the radioisotopes from the nuclear fuel was largely controlled by their boiling points, and the majority of the radioactivity present in the core was retained in the reactor.

• All of the noble gases, including krypton and xenon, contained within the reactor were released immediately into the atmosphere by the first steam explosion.
• About 55% of the radioactive iodine in the reactor was released, as a mixture of vapor, solid particles and as organic iodine compounds.
• Caesium and tellurium were released in aerosol form.

Two sizes of particles were released: small particles of 0.3 to 1.5 micrometers (aerodynamic diameter) and large particles of 10 micrometers. The large particles contained about 80% to 90% of the released nonvolatile radioisotopes zirconium-95, niobium-95, lanthanum-140, cerium-144 and the transuranic elements, including neptunium, plutonium and the minor actinides), embedded in a uranium oxide matrix.

Ill health of plant workers

In the aftermath of the accident, two hundred and thirty-seven people suffered from acute radiation sickness, of whom thirty-one died within the first three months.<ref>Modèle:Cite book</ref><ref>Mould 2000, p. 29. "The number of deaths in the first three months were 31[.]"</ref> Most of these were fire and rescue workers trying to bring the accident under control, who were not fully aware of how dangerous the radiation exposure (from the smoke) was (for a discussion of the more important isotopes in fallout see fission product). 135,000 people were evacuated from the area, including 50,000 from Pripyat.^{[citation needed]}

Residual radioactivity in the environment

Rivers, lakes and reservoirs

The Chernobyl nuclear power plant lies next to the river Pripyat which feeds into the Dnieper river-reservoir system, one of the largest surface water systems in Europe. The radioactive contamination of aquatic systems therefore became a major issue in the immediate aftermath of the accident.<ref name=smithber05>Chernobyl: Catastrophe and Consequences, Springer, Berlin ISBN 3-540-23866-2 </ref> In the most affected areas of Ukraine, levels of radioactivity (particularly radioiodine: I-131, radiocaesium: Cs-137 and radiostrontium: Sr-90) in drinking water caused concern during the weeks and months after the accident. After this initial period, however, radioactivity in rivers and reservoirs was generally below guideline limits for safe drinking water.<ref name=smithber05/>

Bio-accumulation of radioactivity in fish<ref name=kryshev95>Kryshev, I.I., Radioactive contamination of aquatic ecosystems following the Chernobyl accident. Journal of Environmental Radioactivity, 1995. 27: p. 207-219</ref> resulted in concentrations (both in western Europe and in the former Soviet Union) that in many cases were significantly above guideline maximum levels for consumption.<ref name=smithber05/> Guideline maximum levels for radiocaesium in fish vary from country to country but are approximately 1,000 Bq/kg or 1 kBq/kg in the European Union.<ref name=euregs>EURATOM Council Regulations No. 3958/87, No. 994/89, No. 2218/89, No. 770/90</ref> In the Kiev Reservoir in Ukraine, activity concentrations in fish were several thousand Bq/kg during the years after the accident.<ref name=kryshev95/> In small "closed" lakes in Belarus and the Bryansk region of Russia, activity concentrations in a number of fish species varied from 0.1 to 60 kBq/kg during the period 1990–92.<ref name=fleishman94>Fleishman, D.G., et al., Cs-137 in fish of some lakes and rivers of the Bryansk region and North-West Russia in 1990–1992. Journal of Environmental Radioactivity, 1994. 24: p. 145-158</ref> The contamination of fish caused concern in the short term (months) for parts of the UK and Germany and in the long term (years-decades) in the Chernobyl affected areas of Ukraine, Belarus and Russia as well as in parts of Scandinavia.<ref name=smithber05/>

Groundwater

Groundwater was not badly affected by the Chernobyl accident since radionuclides with short half-lives decayed away a long time before they could affect groundwater supplies, and longer-lived radionuclides such as radiocaesium and radiostrontium were adsorbed to surface soils before they could transfer to groundwaters.<ref name=iaea06>Modèle:PDFlink [1]IAEA, Vienna</ref> Significant transfers of radionuclides to groundwaters have occurred from waste disposal sites in the Modèle:Convert/km exclusion zone around Chernobyl. Although there is a potential for off-site (i.e. out of the Modèle:Convert/km exclusion zone) transfer of radionuclides from these disposal sites, the IAEA Chernobyl Report<ref name=iaea06/> argues that this is not significant in comparison to current levels of washout of surface-deposited radioactivity.

Flora and Fauna

After the disaster, four square kilometres of pine forest in the immediate vicinity of the reactor turned ginger brown and died, earning the name of the "Red Forest", according to the BBC.<ref name=bbcmulvey>Wildlife defies Chernobyl radiation, by Stefen Mulvey, BBC News </ref> Some animals in the worst-hit areas also died or stopped reproducing. Most domestic animals were evacuated from the exclusion zone, but horses left on an island in the Pripyat River 6 km from the power plant died when their thyroid glands were destroyed by radiation doses of 150-200 Sv.<ref name=iaea1991>The International Chernobyl Project Technical Report, IAEA, Vienna, 1991 </ref> Some cattle on the same island died and those that survived were stunted because of thyroid damage. The next generation appeared to be normal.<ref name=iaea1991/>

In the years since the disaster, the exclusion zone abandoned by humans has become a haven for wildlife, with nature reserves declared (Belarus) or proposed (Ukraine) for the area. Many species of wild animals and birds, which were not seen in the area prior to the disaster, are now plentiful, due to the absence of humans in the area.<ref name=bbcmulvey/>

A robot sent into the reactor itself has returned with samples of black, melanin-rich fungi that are growing on the reactor's walls^{[citation needed]}.

Chernobyl after the disaster

Following the accident, questions arose on the future of the plant and its eventual fate. All work on the unfinished reactors 5 and 6 was immediately halted. However, the trouble at the Chernobyl plant did not end with the disaster in reactor 4. The damaged reactor was sealed off and Modèle:Formatnum:200 metres ({{formatnum:{{rnd/+|200*1/0.3048|-1|Modèle:Rnd/00}}}} ft) of concrete was placed between the disaster site and the operational buildings. The Ukrainian government continued to let the three remaining reactors operate because of an energy shortage in the country. A fire broke out in reactor 2 in 1991; the authorities subsequently declared the reactor damaged beyond repair and had it taken offline. Reactor 1 was decommissioned in November 1996 as part of a deal between the Ukrainian government and international organizations such as the IAEA to end operations at the plant. On December 15, 2000, then-President Leonid Kuchma personally turned off Reactor 3 in an official ceremony, effectively shutting down the entire plant. This transformed the Chernobyl plant from energy producer to energy consumer.

The need for future repairs

The sarcophagus is not an effective permanent enclosure for the destroyed reactor. Its hasty construction, in many cases conducted remotely with industrial robots, is aging poorly. If it collapses another cloud of radioactive dust could be released. The sarcophagus is in such poor condition that a small earthquake or severe wind could cause the roof to collapse. A number of plans have been discussed for building a more permanent enclosure.

Water continues to leak into the shelter, spreading radioactive materials throughout the wrecked reactor building and potentially into the surrounding groundwater. The basement of the reactor building is slowly filling with water that is contaminated with nuclear fuel and is considered high-level radioactive waste. Though repairs were undertaken to fix some of the most gaping holes that had formed in the roof, it is by no means watertight, and will only continue to deteriorate.

The sarcophagus, while not airtight, heats up much more readily than it cools down. This is contributing to rising humidity levels inside the shelter. The high humidity inside the shelter continues to erode the concrete and steel of the sarcophagus.

Further, dust is becoming an increasing problem within the shelter. Radioactive particles of varying size are a portion of the debris inside the shelter. Convection currents compounded with increasing intrusion of outside airflow are increasingly stirring up and suspending the particles in the air inside the shelter. The installation of air filtration systems in 2001 has reduced the problem, but not eliminated it.

Some signs of a criticality were observed in June 24 1990–July 1 1990 inside room 304/3;<ref>Russian Research Centre Kurchatov Institute</ref> to avoid any further nuclear fission reaction, a neutron poison was added to this room.

In September 2007, Ukraine approved the building of a steel casing over the reactor. The casing, to be built by the French firm Novarka, will be at a cost of $1.4bn. The arch shaped structure, which will measure Modèle:Convert/LoffAonDbSoff wide and Modèle:Convert/LoffAonDbSoff long, is scheduled to take 5 years to complete. Once the structure is complete, dismantling of Reactor 4 will begin.<ref>http://news.bbc.co.uk/2/hi/europe/6999140.stm</ref>

The lava (or fuel containing materials FCM)

According to official estimates, about 95% of the fuel (about 180 tonnes) in the reactor at the time of the accident remains inside the shelter, with a total radioactivity of nearly 18 million curies (670000 TBq). The radioactive material consists of core fragments, dust, and lava-like "fuel-containing materials" (FCM) that flowed through the wrecked reactor building before hardening into a ceramic form.

Three different lavas are present in the basement of the reactor building, these are black, brown and a porous ceramic. These lavas are silicate glasses with inclusions of other materials present within them. The porous lava is brown lava which had dropped into water thus cooling it rapidly.

Degradation of the lava

It is unclear how long the ceramic form will retard the release of radioactivity. In 1997 to 2002 a series of papers were published which suggested that the α self irradiation of the lava would convert all 1200 tons into a submicron and mobile powder within a few weeks.<ref>V.Baryakhtar, V.Gonchar, A.Zhidkov and V.Zhidkov, Radiation damages and self-spluttering of high radioactive dielectrics: Spontaneous emission of submicron dust particles, Condensed Matter Physics, 2002, 5(3{31}), 449-471.</ref> But it has been reported that it is likely that the degradation of the lava is to be a slow and gradual process rather than a sudden rapid process.<ref>A.A. Borovoi, Nuclear fuel in the shelter, Atomic Energy, 2006, 100, 249.</ref> The same paper states that the loss of uranium from the wrecked reactor is only Modèle:Kg to lb per year. This low rate of uranium leaching suggests that the lava is resisting its environment. The paper also states that when the shelter is improved that the leaching rate of the lava will decrease.

Some of the surfaces of the lava flows have started to show new uranium minerals such as Na₄(UO₂)(CO₃)₃ and uranyl carbonate. These have been seen on the elephant foot already. However the level of radioactivity is such that during 100 years that the self irradiation of the lava (2 x 10¹⁶ α decays per gram and 2 to 5 x 10⁵ Gy of β or γ) will fall short of the level of self irradiation which is required to greatly change the properties of glass (10¹⁸ α decays per gram and 10⁸ to 10⁹ Gy of β or γ). Also the rate of dissolution of the lava in water is very low (10^-7 g cm^-2 day^-1 suggesting that the lava is unlikely to dissolve in water.<ref>A.A. Borovoi, Nuclear fuel in the shelter, Atomic Energy, 2006, 100, 249.</ref>.The IAEA and the former soviets maintain that less than 5% of the fuel was lost due to the explosion.

Possible consequences of further collapse of the Sarcophagus

The protective box which was placed over the wrecked reactor was named the object shelter by the Soviets, but the media and the public know it as the sarcophagus.

The present shelter is constructed atop the ruins of the reactor building. The two "Mammoth Beams" that support the roof of the shelter are resting partly upon the structurally unsound west wall of the reactor building that was damaged by the accident. The western end of the shelter roof was supported by a wall (at a point designated axis 50). This wall is a reinforced concrete wall which was cracked by the accident. In December 2006 the Designed Stabilisation Steel Structure (DSSS) was extended until 50% of the roof load (circa 400 tons) was transferred from the axis-50 wall to the DSSS. The DSSS is a yellow steel object which has been placed next to the wrecked reactor, it is Modèle:Formatnum:63 metres ({{formatnum:{{rnd/+|63*1/0.3048|0|Modèle:Rnd/00}}}} ft) tall and has a series of cantilevers which extend through the western buttress wall and is intended to stablise the object shelter. <ref>Nuclear Engineering International, July 2007, page 12</ref>. This was done because if the wall of the reactor building and subsequently the roof of the shelter were to collapse, then large amounts of radioactive dust and particles would be released directly into the atmosphere, resulting in a large new release of radioactivity into the environment.

A further threat to the shelter is the concrete slab that formed the "Upper Biological Shield" (UBS), and rested atop the reactor prior to the accident. This concrete slab was thrown upwards by the explosion in the reactor core and now rests at approximately 15° from vertical. The position of the upper bioshield is considered inherently unsafe, in that only debris is supporting it in a nearly upright position. The collapse of the bioshield would further exacerbate the dust conditions in the shelter, would probably spread some quantity of radioactive materials out of the shelter, and could damage the shelter itself.

The sarcophagus was never designed to last for the 100 years needed to contain the radioactivity found within the remains of reactor 4. While present designs for a new shelter anticipate a lifetime of up to 100 years, that time is minuscule compared to the lifetime of the radioactive materials within the reactor. The construction and maintenance of a permanent sarcophagus that can completely contain the remains of reactor 4 will present a continuing task to engineers for many generations to come.

Grass and forest fires

If the Chernobyl plant were to collapse, a large release of radioactive dust would occur, but it would likely be a one-time event. It is possible for grass or forest fires to occur on a regular basis within the contaminated zone. In 1986 a series of fires destroyed 23.36 km² (5,772 acres) of forest, and a series of other fires have since burned within the Modèle:Convert/km zone. During early May 1992 a serious fire occurred which affected 5 km² (1,240 acres) of land which included 2.7 km² (670 acres) of forest. This resulted in a great increase in the levels of caesium in airborne dust.[2]Modèle:PDFlinkModèle:PDFlink[3]

It is known that fires can make the radioactivity mobile again.<ref>Modèle:PDFlink</ref><ref> Sergei I. Dusha-Gudym

     (August 1992)
   
.    Forest Fires on the Areas Contaminated by Radionuclides from the Chernobyl Nuclear Power Plant Accident 

.</ref><ref> Eduard P. Davidenko, Johann Georg Goldammer

     (January 1994)
   
.    News from the Forest Fire Situation in the Radioactively Contaminated Regions 

.</ref><ref> Mikhail Antonov, Maria Gousseva

     (2002-09-18)
   
.    Radioactive fires threaten Russia and Europe 
. Pravda.ru 
   

.</ref> In particular V.I. Yoschenko et al. reported on the possibility of increased mobility of caesium, strontium, and plutonium due to grass and forest fires.<ref>Yoschenko et al., Journal of Environmental Radioactivity, 2006, 86, 143-163</ref> As an experiment, fires were set and the levels of the radioactivity in the air down wind of these fires was measured.

The Chernobyl Fund and the Shelter Implementation Plan

Main article: New Safe Confinement

The Chernobyl Shelter Fund was established in 1997 at the Denver G7 summit to fund the Shelter Implementation Fund. The Shelter Implementation Plan (SIP) calls for transforming the site into an ecologically safe condition through stabilization of the sarcophagus, followed by construction of a New Safe Confinement (NSC). While original cost estimate for the SIP was US$768 million, the 2006 estimate is $1.2 billion. The SIP is being managed by a consortium of Bechtel, Battelle, and Electricité de France, and conceptual design for the NSC consists of a movable arch, constructed away from the shelter to avoid high radiation, to be slid over the sarcophagus. The NSC is expected to be completed in early 2008, and will be the largest movable structure ever built.

Dimensions:

• Span: Modèle:Convert/LoffAonDbSoff
• Height: Modèle:Convert/LoffAonDbSoff
• Length: Modèle:Convert/LoffAonDbSoff

Assessing the disaster's effects on human health

Modèle:POV

Main article: Chernobyl disaster effects

An international assessment of the health effects of the Chernobyl accident is contained in a series of reports by the United Nations Scientific Committee of the Effects of Atomic Radiation (UNSCEAR). <ref name=UNSCEAR>"UNSCEAR assessment of the Chernobyl accident"</ref> UNSCEAR was set up as a collaboration between various UN bodies, including the World Health Organisation, after the atomic bomb attacks on Hiroshima and Nagasaki, to assess the long-term effects of radiation on human health.

UNSCEAR has conducted 20 years of detailed scientific and epidemiological research on the effects of the Chernobyl accident. Apart from the 57 direct deaths in the accident itself, UNSCEAR originally predicted up to 4,000 additional cancer cases due to the accident,<ref name="iaea"> IAEA Report

. In Focus: Chernobyl

 

. Retrieved on 2006-03-29. </ref> however the latest UNSCEAR reports insinuate that these estimates were overstated.<ref name="Chernobyl health effects"> "UNSCEAR - Chernobyl health effects"</ref> In addition, the IAEA states that there has been no increase in the rate of birth defects or abnormalities, or solid cancers (such as lung cancer) corroborating UNSCEAR's assessments. <ref name="Chernobyl’s Legacy">"IAEA - Chernobyl's Legacy"</ref>

Precisely, UNSCEAR states:

"Among the residents of Belarus, the Russian Federation and Ukraine, there had been up to the year 2002 about 4,000 cases of thyroid cancer reported in children and adolescents who were exposed at the time of the accident, and more cases can be expected during the next decades. Notwithstanding problems associated with screening, many of those cancers were most likely caused by radiation exposures shortly after the accident. Apart from this increase, there is no evidence of a major public health impact attributable to radiation exposure 20 years after the accident. There is no scientific evidence of increases in overall cancer incidence or mortality rates or in rates of non-malignant disorders that could be related to radiation exposure. The risk of leukaemia in the general population, one of the main concerns owing to its short latency time, does not appear to be elevated. Although those most highly exposed individuals are at an increased risk of radiation-associated effects, the great majority of the population is not likely to experience serious health consequences as a result of radiation from the Chernobyl accident. Many other health problems have been noted in the populations that are not related to radiation exposure."<ref name="Chernobyl health effects"> "UNSCEAR - Chernobyl health effects"</ref>

Thyroid cancer is generally treatable^{[citation needed]}.

"The Chernobyl Forum" <ref name="Chernobyl Forum"> [4] "Chernobyl Forum summaries"</ref> is a regular meeting of IAEA, other United Nations organizations (FAO, UN-OCHA, UNDP, UNEP, UNSCEAR, WHO and The World Bank) and the governments of Belarus, Russia, and Ukraine, which issues regular assessments of the evidence for health effects of the Chernobyl accident.

"The Chernobyl Forum" has concluded that a greater risk than the long-term effects of radiation exposure, is the risk to mental health of exaggerated fears about the effects of radiation:<ref name="Chernobyl Forum">[5] Chernobyl Forum booklets</ref>

" ... The designation of the affected population as “victims” rather than “survivors” has led them to perceive themselves as helpless, weak and lacking control over their future. This, in turn, has led either to over cautious behavior and exaggerated health concerns, or to reckless conduct, such as consumption of mushrooms, berries and game from areas still designated as highly contaminated, overuse of alcohol and tobacco, and unprotected promiscuous sexual activity."

While it was commented by Fred Mettler (http://www.iaea.org/Publications/Magazines/Bulletin/Bull472/htmls/chernobyls_legacy2.html) that 20 years later

The population remains largely unsure of what the effects of radiation actually are and retain a sense of foreboding. A number of adolescents and young adults who have been exposed to modest or small amounts of radiation feel that they are somehow fatally flawed and there is no downside to using illicit drugs or having unprotected sex. To reverse such attitudes and behaviors will likely take years although some youth groups have begun programs that have promise.

In addition, many charities which help the "Children of Chernobyl" may be helping disadvantaged children, but the health problems of such children are not only to do with the Chernobyl accident, but also with the desperately poor state of post-Soviet health systems.<ref name="Chernobyl Forum">[6] "Chernobyl Forum booklets"</ref>

Reports by anti-nuclear power protest groups and irresponsible journalists <ref name="John Vidal - The Guardian"> "John Vidal, The Guardian"</ref>, based on speculation rather than evidence, may have contributed to the anxiety and depression of people in the fallout zones. These include the TORCH report, the Greenpeace report, and the April 2006 International Physicians for Prevention of Nuclear Warfare (IPPNW) report.<ref name="iaea"> IAEA Report

. In Focus: Chernobyl

 

. Retrieved on 2006-03-29. </ref> Modèle:Dubious

In response to the Chernobyl Forum, The Other Report on Chernobyl (TORCH) was produced. It predicted between 30,000 to 60,000 excess cancer deaths, and urged more research stating that large uncertainties made it difficult to properly assess the full scale of the disaster.<ref name=TORCH> TORCH report executive summary

. European Greens and UK scientists Ian Fairlie PhD and David Sumner 
 
 (April 2006)
   

. Retrieved on April 21, 2006.

</ref> Another study critical of the Chernobyl Forum report was commissioned by Greenpeace. In its report, Greenpeace argued that "the most recently published figures indicate that in Belarus, Russia and Ukraine alone the accident could have resulted in an estimated 200,000 additional deaths in the period between 1990 and 2004." However, the Greenpeace report failed to discriminate between the general increase in cancer rates that followed the dissolution of the USSR's health system and any separate effects of the Chernobyl accident. <ref name="Chernobyl health effects"> [7]</ref> Lastly, in its report Health Effects of Chernobyl, the German affiliate of the IPPNW argued that more than 10,000 people are today affected by thyroid cancer and 50,000 cases are expected in the future.<ref>    20 years after Chernobyl – The ongoing health effects 
. IPPNW 
 
 (April , 2006)
   

. Retrieved on 2006-04-24.

</ref> According to some commentators, both the Greenpeace and IPPNW reports suffer from a lack of any genuine or original research and failure to understand epidemiologic data.<ref name="Chernobyl health effects"> [8]"UNSCEAR - health effects of Chernobyl"</ref> This said, it is important to bear in mind that many of the conclusions from reports such as UNSCEAR remain disputed by other commentators and scientists in the field<ref>http://news.bbc.co.uk/1/shared/bsp/hi/pdfs/18_04_06_chernobyl.pdf</ref>.

Comparison with other disasters

The Chernobyl disaster caused a few tens of immediate deaths due to radiation poisoning; a few thousand premature deaths are predicted over the coming decades. Since it is often not possible to prove the origin of the cancer which causes a person's death, it is difficult to estimate Chernobyl's long-term death toll.

Other man-made disasters with very high death tolls include:

• The failure of the Banqiao Dam (Henan, China, 1975) – where an estimated 26,000 people died from flooding and another 145,000 died during subsequent epidemics and famine.
• The Bhopal disaster (India, 1984) – the BBC gives the death toll as nearly 3,000 people dead initially, and at least another 15,000 have died from related illnesses since.
• The Great Smog (London, United Kingdom, 1952) – where medical services compiled statistics and found that the fog had killed 4,000 people initially, and another 8,000 died in the weeks and months that followed.
• The Johnstown Flood (Pennsylvania, United States, 1889) – 2,209 killed.

Comparisons with other various incidents concerning radioactivity are at Chernobyl compared to other radioactivity releases.

In the popular consciousness

Main article: Chernobyl in the popular consciousness

The Chernobyl accident attracted a great deal of interest. Because of the distrust that many people had in the Soviet authorities (people both within and outside the USSR) a great deal of debate about the situation at the site occurred in the first world during the early days of the event. Due to defective intelligence based upon photographs taken from space, it was thought that unit number three had also suffered a dire accident.

A few, poorly regarded authors claim that the official reports underestimate the scale of the Chernobyl tragedy, counting only 30 victims;<ref> Marcin Rotkiewicz, Henryk Suchar and Ryszard Kamiñski. "CHERNOBYL THE BIGGEST BLUFF of the XXth CENTURY" Polish weekly WPROST, no 2 (14 January) 2001, http://www.wonuc.org/xfiles/chern_02.html </ref> some estimate the Chernobyl radioactive fallout as hundreds of times that of the atomic bomb dropped on Hiroshima, Japan,<ref> Hell on Earth. The Guardian. Wednesday April 26 2006, http://society.guardian.co.uk/societyguardian/story/0,,1760930,00.html </ref><ref>Hirishima International council. Comparison of Damage among Hiroshima/Nagasaki, Chernobyl, and Semipalatinsk. http://www.hiroshima-cdas.or.jp/HICARE/en/10/hi04.html </ref> counting millions of exposed.

In general the public knew little about radioactivity and radiation and as a result their degree of fear was increased. It was the case that many professionals (such as the spokesman from the UK NRPB) were mistrusted by journalists, who in turn encouraged the public to mistrust them.<ref>Modèle:Cite book</ref>

It was noted<ref>Modèle:PDFlink </ref> that different governments tried to set contamination level limits which were stricter than the next country. In the dash to be seen to be protecting the public from radioactive food, it was often the case that the risk caused by the modification of the nations' diet was greater and un-noticed.^{[citation needed]}

Some alternative views on Chernobyl

Modèle:POV Strong arguments do exist in support of (at the very least) some aspects of 'alternative' assessments such as the TORCH report. The ECRR's publication "Chernobyl: 20 Years On"<ref>"Chernobyl: 20 Years On", European Committee on Radiation Risk. </ref> has summarised thousands of Ukrainian, Belarusian and Russian papers, and scientists studying those regions who have claimed, among other effects, genetic defects in plants and animals transmitted over 22 generations. However, these findings have not been confirmed by all workers within the subject, it is known that many species of wild animals found within the Modèle:Convert/km exclusion zone are alive and well.<ref name=bbcmulvey/>

Furthermore, it has been reported by the UN that in the contaminated areas in the general public that "no evidence or likelihood of decreased fertility has been seen among males or females. Also, because the doses were so low, there was no evidence of any effect on the number of stillbirths, adverse pregnancy outcomes, delivery complications or overall health of children. A modest but steady increase in reported congenital malformations in both contaminated and uncontaminated areas of Belarus appears related to better reporting, not radiation."[9]

The LLRC have claimed that a 40% increase in Belarusian cancer rates has occurred<ref>[10] Cancer in Belarus increased 40% after Chernobyl</ref>, with a similar increase in northern Sweden. However it is important to bear in mind that some of the LLRC's work on cancer in humans could not be repeated by other scientists.[11]

It is also important to note that the (presumed) low effect of chronic doses of radiation may be different to acute exposure due to self repair processes, and scientific opinion is divided on the subject of how dangerous small doses<ref>Radioactivity in the Body, Hanford Health Information Network [12]</ref> (delivered at low dose rates) of radiation are. One common model is the LNT model which states that the increased likelihood of disease is directly proportional to the dose, while other models suggest that below a threshold that radiation is harmless or even good for human health. However, the effects of internal doses of radiation on the body (due to inhaled/ ingested isotopes) are often very different from their external effects<ref>[13] Radiation Accident Management - Decontamination</ref>, even at low doses.

Some caution is needed in adopting a purely local view of the Chernobyl disaster, as the major effects of the accident go far beyond the intense on-site radiation fields (these were sometimes in the range of circa 10 Gy min^-1 on day one, but they have now decayed to far lower levels). While the majority of the emitted radioactivity was deposited close to the reactor<ref>A.A. Borovoi, Nuclear fuel in the shelter, Atomic Energy, 2006, 100, 249.</ref> some activity was deposited at remote locations such as Wales, Sweden and other parts of Western Europe. It is now the case that Chernobyl cesium-137 can be found in many topsoils and sedimentary deposits in Europe, which has been documented in numerous studies.<ref>R. Salminen et al. Geochemical Atlas of Eastern Barents region p204</ref><ref>Ilus E. and Saxén R. J Env. Rad. 2005. Vol 82 pp 199-221. Accumulation of Chernobyl-derived 137Cs in bottom sediments of some Finnish lakes</ref> While the fallout outside the former Soviet Union did not result in radiation fields with the intensity to cause deterministic effects such as radiation sickness, it has resulted in a situation where restrictions on the sale and movement of food were considered wise and necessary in some cases, and many governments imposed cautious new regulations.^{[citation needed]}

Due to the long latent period between exposure and the clinical appearance of many radiation related diseases (mainly cancer), it is unwise to rule out at least the possibility of additional major long-term health effects (both within and outside the Chernobyl region). In any case, while there is no doubt that socio-economic stress - coupled with the psychological effects of anxiety and relocation - must play a part in the Chernobyl health debacle, the indirect health impacts of clean-up costs over many years (through diverted expenditure) cannot be dismissed as somehow 'outside' the event. These 'collateral impacts' are part and parcel of the socio-economic aftermath of disasters on this scale and (where they have occurred) need to be incorporated in the impact equation. These costs are real and include an erosion of national confidence, loss of trade and land area (Exclusion Zones contaminated above the WHO limits), an intensification of existing health issues and the 'socio-economic deaths' which arise through social underprovision.

References

See also

External links

Modèle:External links

General information

• Official UN Chernobyl site
• Modèle:PDFlink, by the Chernobyl Forum (UN), updated in 2006
• WikiSattelite view of Chernobyl disaster at WikiMapia
• Modèle:PDFlink
• Modèle:PDFlink, by Greenpeace International, April 2006.
• Fall-out data in 19 zones from Austria to Eastern USA
• The International Chernobyl Research and Information Network
• Frequently Asked Chernobyl Questions, by the IAEA
• The United Nations and Chernobyl In English, French and Russian,
• Modèle:PDFlink – UN Report, 2002
• Modèle:Ru icon Video of shutting down the last reactor at Chernobyl

Event and technical analysis

• Western responsibility regarding the health consequences of the Chernobyl catastrophe in Belarus, the Ukraine and Russia
• Modèle:En icon/Modèle:Fr icon Surveillance sanitaire en France en lien avec l’accident de Tchernobyl – Bilan actualisé sur les cancers thyroïdiens et études épidémiologiques en cours en 2006. April 2006 report by the French Institut de veille sanitaire on Chernobyl's consequences in France and thyroid cancers
• Modèle:En icon/Modèle:Fr icon Various reports (Chernobyl 5 years after, 10 years after, 20 years after, etc. by the Institut de radioprotection et de sûreté nucléaire (English version – click on top right)
• "The nuclear reactor accident at Chernobyl, USSR" by Bernard L. Cohen, American Journal of Physics Vol. 55, No. 12, December 1987. A good pedagogical article aimed at an undergraduate physics-student level.
• Modèle:PDFlink

Witness accounts (before and after)

Books

• Mario Petrucci (2004). Heavy Water: a poem for Chernobyl. ISBN 1-900564-34-3 (Enitharmon Press; Winner of the 2002 Arvon/ Daily Telegraph Prize).
• Svetlana Alexievich (1997). Voices from Chernobyl: The Oral History of a Nuclear Disaster. ISBN 1-56478-401-0 (2005 English translation by Keith Gessen)
• Mary Mycio (2005). Wormwood Forest: A Natural History of Chernobyl. ISBN 0-309-09430-5
• Grigori Medvedev (1991). The Truth About Chernobyl. ISBN 0-465-08776-0
• Adriana Petryna (2002). Life Exposed. ISBN 0-691-09018-1

Websites and other

• NY Times Headline, April 29, 1986, Soviet Announces Nuclear Accident at Electric Plant
• "20 Years 20 Lives" – Eyewitness accounts in words and photographs, from the Chernobyl Children's Project International.
• "Kidofspeed" – Ukrainian motorcyclist Elena Filatova rode through the Chernobyl "Zone", in words and photographs.
• How I survived Chernobyl, from The Guardian, August 24, 2004. Interview with Sasha Yuvchenko an engineer working at the Chernobyl plant in 1986.

Photography/videography/infography

• Heavy Water: a film for Chernobyl David Bickerstaff, Phil Grabsky, Mario Petrucci (Seventh Art Productions, 2006) - the award-winning film based on Mario Petrucci's book-length poem.
• Photos of Pripyat and Chernobyl, by Alexandr Vikulov, 2006
• Nuclear devastation in the former USSR, by Robert Knoth and Antoinette de Jong
• My Journey to Chernobyl: 20 Years After the Disaster – A photo journal by Mark Resnicoff
• Chernobyl Legacy, 2006, by photojournalist Paul Fusco. Narrated interactive essay, focused on the continuing human tragedy in Belarus.
• Photos of a visit to the reactor of Chernobyl in April 2006 by a German TV team joint by Research Center Juelich
• Humus Project - VideoReportages of Chernobyl disaster
• Animated Flash map – 2 minutes and 30 seconds – of Caesium-137 contamination published by the French Institut de radioprotection et de sûreté nucléaire (IRSN)
• Photos from Pripyat city and Chernobyl zone – Two trips in 2005
• Chernobyl – Chernobyl photo gallery
• Nuclear Nightmares: Twenty Years Since Chernobyl
• BBC On This Day: Including recordings of the first public announcement
• Modèle:Ru icon More Dead Zone pictures
• 2006 images of Chernobyl today
• Chernobyl Gallery – Several images, many from inside the reactor
• Chernobyl Heart (2003) – Academy Award-winning documentary
• The Long Shadow of Chernobyl by Richard Stone and Gerd Ludwig for the April 2006 issue of National Geographic Magazine
• Nine Network Australia, 60 Minutes, Inside Chernobyl, airdate April 16, 2006. Reporter Richard Carlton goes inside the control centre at Chernobyl and also visits the exclusion zone surrounding the plant. Focuses on the 1986 incident, the failing "sarcophagus" and yet-to-be–realised plans to replace it, and the affected children in orphanages in nearby Belarus
• Satellite view of Chernobyl, Google Maps
• Modèle:Cs icon Various videos from Chernobyl.
• Pictures from Chernobyl & Pripyat by Oscar Mannbro.
• Chernobyl: 20 years on - photo journal by Phil Coomes
• Flickr: The Chernobyl Pool
• To Chernobyl - a journey to the exclusionzone, photo's and traveljournal
• Pictures from Chernobyl and Pripiat, July 2006 by Hans Fredriksson, Sweden

Charitable and voluntary organizations concerned with the effects

• Chernobyl Children's Project International – Subject of documentary "Chernobyl Heart"
• Cry Of Chernobyl Charity Internet Project "Cry Of Chernobyl"
• Aratta – Ukrainian charity for families near Chernobyl (site in Russian, see this UK charity for info on their work in English)
• Humanity for Chernobyl organisation U.S.-based charity funding aid to liquidators, their families and other victims.
• Chabad Children of Chernobyl Provides evacuation and care to children from affected areas
• Children of Chernobyl - San Diego Non-profit travel program for children living in affected cities.

Artists' responses to the disaster

• 'Heavy Water: a film for Chernobyl' - the award-winning film by Phil Grabsky, David Bickerstaff & Mario Petrucci (Seventh Art Productions, 2006)
• 'Three Hot Drops of Salmon Oil': the artist and the self in the aftermath of Chernobyl Interdisciplinary Science Reviews, 31/3 (2006).

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