Chernobyl: Myths and facts

World April 26, 2016, 18:48

The myths surrounding the Chernobyl nuclear disaster and the lessons learnt from it are highlighted in TASS feature

April 26, 2016 marks 30 years since the Chernobyl nuclear power plant disaster. Specialists from all over the world have been eliminating the consequences of the worst man-made disaster in the history of the peaceful use of nuclear energy up to this day.

The Russian nuclear power industry has implemented a modernization program, revised actually fully outdated technological solutions and developed systems, which, as specialists say, completely rule out the possibility of a similar catastrophe.

 The myths surrounding the Chernobyl nuclear disaster and the lessons learnt from it are highlighted in TASS special project.

Worst disaster in the history of the peaceful use of nuclear energy

The construction of the first stage of the Chernobyl Nuclear Power Plant began in 1970 and the town of Pripyat was built nearby for the plant’s personnel. 

On September 27, 1977, the first power unit with the RBMK-1000 nuclear reactor with a capacity of 1,000 MW was connected to the power grid of the Soviet Union. Subsequently, three more power units came into operation and the Chernobyl NPP’s annual electric power generation totaled 29 billion kWh.

On September 9, 1982, the first accident occurred at the Chernobyl NPP: during the test launch of the 1st power unit, one of the reactor’s technological channels was destroyed and the graphite stack of the reactor core was deformed. None of the personnel was hurt and it took about three months to eliminate the consequences of the accident.

Overnight to April 26, 1986, tests of the turbine generator were held at the 4th power unit of the Chernobyl NPP. It was planned to halt the reactor (meanwhile, the emergency cooling system was switched off in a planned manner) and measure the generator’s indicators. Attempts failed to shut down the reactor safely. At 01:23 hours Moscow time, an explosion occurred at the 4th power unit followed by a fire.

The accident became the worst disaster in the history of the nuclear power industry: the reactor core was completely destroyed, the power unit’s building partially collapsed and a considerable amount of radioactive substances was discharged into the atmosphere, contaminating the environment.

  • One person - pump operator Valery Khodemchuk - died in the explosion (rescuers failed to find his body under the debris) and in the morning of the same day, automation system service engineer Vladimir Shashenok died of burns and a spinal cord injury in a medical station.
  • On April 27, the town of Pripyat was evacuated (47,500 people) and in the subsequent days the evacuation of the population within the 10-km zone around the Chernobyl NPP took place. Overall, about 116,000 people were resettled during May 1986 from 188 populated settlements within the 30-km exclusion area around the nuclear power plant.
  • The intensive fire lasted 10 days, during which about 14 exabecquerels (about 380 million curies) of radioactive materials were released into the environment.
  • Radioactive contamination spread over the area of more than 200,000 sq. km. of which 70% was the territory of Ukraine, Belorussia and Russia.
  • The most severely contaminated areas were the northern districts of the Kiev and Zhitomir Regions of the Ukrainian SSR, the Gomel Region of the Belorussian SSR and the Bryansk Region in the RSFSR.
  • The radiation fallout was registered in the Leningrad Region, Mordovia and Chuvashia.
  • Subsequently, contamination was observed in the USSR Arctic regions, Norway, Finland and Sweden.
  • The first brief official notice about the accident was reported by TASS on April 28. As former CPSU Central Committee Secretary-General Mikhail Gorbachev said in an interview with the BBC in 2006, the festive Labor Day manifestations on May 1 in Kiev and other cities in the Soviet Union were not cancelled as the country’s leadership didn’t have “a full picture of what happened” and feared panic among the population. It was only on May 14 that Soviet leader Mikhail Gorbachev made a televised address, in which he told about the true scope of the accident.
  • The Soviet state commission for the investigation of the causes for the nuclear disaster put the blame for the disaster on the nuclear power plant’s administration and operational personnel. The International Nuclear Safety Advisory Group (INSAG) set up by the International Atomic Energy Agency (IAEA) confirmed in its 1986 report the conclusions of the Soviet commission.

Work in hell

Fire fighters were among the first to take part in the efforts to eliminate the consequences of the nuclear disaster. The signal about a fire at the NPP was received at 01:28 a.m. on April 26, 1986. Already 240 fire fighters from the Kiev regional fire protection department were at the scene of the disaster by the morning. They managed to fully extinguish the fire at the 4th power unit of the Chernobyl NPP by 06:35 a.m.

The government commission turned to chemical defense troops to assess the radiation situation and to military helicopter crews to help extinguish the fire in the reactor core zone. Several thousand people were already working at the disaster scene by that time.

The personnel of the radiation control service, civil defense forces, the Defense Ministry’s chemical warfare troops, the State Service for Hydrometeorology and Environmental Monitoring and the Health Ministry worked in the disaster area.

Aside from eliminating the consequences of the nuclear disaster, their task also consisted in measuring the radiation situation at the NPP and surveying the radioactive contamination of natural environments, evacuating the population and protecting the alienation zone that had been set up after the catastrophe. Doctors exercised control over persons that had been exposed to radiation and carried out the necessary medical treatment and prevention measures.

In particular, the following number of people was involved at various stages of eliminating the consequences of the disaster:

  • from 16,000 to 30,000 persons from various organizations were involved in decontamination works.
  • over 210 military units and formations with a total of 340,000 servicemen, including more than 90,000 troops involved in the acutest period from April to December 1986.
  • 18,500 Interior Ministry personnel
  • over 7,000 radiologic laboratories and sanitary-epidemiological stations
  • a total of about 600,000 liquidators from all over the former Soviet Union took part in extinguishing the fires and clearing the debris.

The NPP’s work was halted immediately after the accident. The pit of the exploded reactor with the burning graphite was filled from aboard helicopters with a mixture of boron carbide, lead and dolomite rock and, after the end of the accident’s active phase, with latex, rubber and other dust-absorbing solutions (a total of about 11,400 tons of dry and liquid materials had been dropped by the end of June).

After the first and the most acute stage, all the efforts for localizing the accident were focused on creating a special protective structure, the so-called sarcophagus (the Shelter).

In late May 1986, a special organization was set up to comprise several construction and assembly units, concrete-batching plants, mechanization, auto transport, electric power supply and other divisions. Works were conducted round the clock, by rotating shifts of 10,000 people.

From July to November 1986, a concrete-made sarcophagus over 50 meters high and measuring 200 m by 200 m was built. It covered the 4th power unit of the Chernobyl NPP and halted the discharges of radioactive substances into the atmosphere. During the sarcophagus construction, an accident occurred: on October 2 a Mi-8 helicopter got entangled with its blades in a crane cable and crashed onto the NPP’s territory, killing four crewmembers.

 The Shelter keeps inside at least 95% of irradiated nuclear fuel from the destroyed reactor, including about 180 tons of uranium-235 and also around 70,000 tons of radioactive metal, concrete, the glassy mass and several dozen tons of radioactive dust with an activity of over 2 million curies.

Shelter under threat

Today major international organizations, from energy groups to financial corporations, continue rendering Ukraine assistance in finally cleaning the Chernobyl disaster area.

The warranty period of the old sarcophagus was designed until 2006. That is why, the G7 countries agreed in 1997 that it was necessary to build Shelter-2 to cover the outdated structure.

At present, work is under way to build a large protective structure, the New Safe Confinement, an arc that will be put above the Shelter. 

Works for building the second sarcophagus were expected to be completed in 2015 but were delayed several times. “A serious shortage of funds” is cited as the main cause for the delay. The new deadline for the work completion is set for November 2017.

The total cost of completing the project with the sarcophagus construction as its integral part equals €2.15 billion. At the same time, the sarcophagus construction proper costs €1.5 billion.

  • by now, €675 million has been provided by the EBRD. If necessary, the Bank is ready to finance the project’s budget shortage.
  • the Russian government passed a decision to make an additional contribution of €10 million to the Chernobyl Fund in 2016-2017 (€5 million each year). 
  • other international donors promise to allocate €180 million.
  • the United States has promised to allocate $40 million.

Recently, some Arab countries and China have expressed their desire to make donations to the Chernobyl Fund.

 

Delusions about the tragedy

A big gap exists between the scientific knowledge about the consequences of the disaster and public opinion. In an overwhelming majority of cases, the public opinion is under the influence of the invented Chernobyl mythology that has little to do with the disaster’s real consequences.

The inadequate perception of the radiation danger has objective, specific historical causes, including the following:

  • the causes and the real consequences of the disaster were hushed up by the state
  • the population lacks knowledge about the basics of the physics of processes occurring both in nuclear power engineering and in the sphere of radiation and radioactive impact
  • the hysteria in the media provoked by these factors
  • numerous social problems of the federal scope became a good soil for the quick creation of myths, etc.

The indirect damage from the disaster associated with socio-psychological and socio-economic consequences is considerably higher than the direct damage from the effects of the Chernobyl radiation.

Delusion 1. Chernobyl had disastrous effects on the health of tens of thousands or even hundreds of thousands.

  • According to the Russian National Radiation and Epidemiological Registry (NRER), radiation sickness has been diagnosed in 134 people who were at the 4th unit during the first 24 hours following the explosion. Twenty eight of them died within months after the disaster (27 in Russia) and 20 others passed away due to various causes over the next 20 years.
  • Over the past 30 years the NRER has identified 122 cases of leukemia in Chernobyl cleanup workers; 37 of them may have been due to radiation exposure. No increase in the rates of other oncological diseases in the cleanup workers in contrast to other groups of the population were identified, though.
  • In 1986-2011 of the 195,000 Russian cleanup workers on the NRER lists 40,000 died due to various causes, with the general mortality rates being no higher than Russia’s average.
  • According to NRER statistics available at the end of 2015, of the 993 cases of thyroid gland cancer in children and teenagers (at the moment of the disaster) 99 may have been exposure-related.

No other effects on the population have been identified, which shatters all widely spread delusions and stereotypes regarding the scale of radiological effects of the accident on people’s health. The same conclusions have been confirmed 30 years after the disaster.

The first deputy director of the Nuclear Power Industry’s Safe Development Problems Institute under the Russian Academy of Sciences, Rafael Arutyunian, says that if the extra doses accumulated by the population of the Chernobyl-affected zones over the years since the disaster are analyzed, it will turn out that of the 2.8 million Russians who found themselves in the affected zones:

  • 2.6 million received less than 10 millisieverts. This is one-fifth to one-seventh of the world’s average dose of exposure to natural background radiation.
  • Less than 2,000 people were exposed to doses above 120 millisieverts. That is 30% to 50% less than the exposure of the population of such countries as Finland.

For this reason, Arutyunian says, the population does not show and cannot show any signs of radiological effects except for the already mentioned thyroid gland cancer. According to specialists at the Radiation Medicine Research Center under Ukraine’s Academy of Medical Science, of the 2.34 million people resident in the contaminated areas of Ukraine about 94,800 died from cancer of various origin over twelve years following the catastrophe; an extra 750 died due to Chernobyl-related cancer.

It is noteworthy that in 2.8 million people regardless of the place where they live radiation-unrelated cancer kills 4,000 to 6,000 a year, in other words, the rate is 90,000 to 170,000 deaths over 30 years.

What exposure doses are lethal

  • The natural radiation background, present everywhere, and certain medical procedures result in every person’s annual exposure to 2-5 millisieverts a year.
  • For those whose occupation implies the handling of radioactive materials the annual equivalent dose should not exceed 20 millisieverts.
  • Eight sieverts is considered as the lethal dose, while a dose of 4-5 sieverts kills half of the exposed.
  • At the Chernobyl NPP about one thousand people who were near the reactor at the moment of the disaster were exposed to doses ranging 2 to 20 sieverts, in some cases lethal.
  • The average exposure of Chernobyl cleanup workers was about 100 millisieverts, while in some cases it reached 500 millisieverts.

Delusion 2. Genetic consequences of Chernobyl for humanity are appalling

Arutyunian says 60 years of research around the world has produced no evidence of any genetic defects in descendants resulting from their parents’ exposure to radiation.

This conclusion is confirmed by the results of continued monitoring of victims of Hiroshima and Nagasaki atom bombings and of the next generation.

No genetic deviations from the nationwide average statistics were observed.

Twenty years after Chernobyl the International Commission on Radiological Protection in its 2007 recommendations lowered the value of hypothetical risks by a value of ten.

In the meantime, there are alternative opinions. According to the findings of Dr. Sc. (Agriculture) Valery Glazko:

  • In the wake of the disaster not all those who could have been born are born.
  • Less sophisticated life forms having greater resistance to the adverse effects of the environment tend to reproduce themselves by and large.
  • The response to the same doses of ionizing radiation depends on how new it is for the population.

Glazko believes that the real effects of Chernobyl on the human population will be available for analysis by 2026, because the generation that came under the direct influence of the accident is just beginning to create families and have children.

Delusion 3. The Chernobyl disaster hit nature far harder than humans

Chernobyl resulted in an unprecedentedly large emission of radionuclides into the atmosphere. For this reason it is considered as the gravest man-made catastrophe in the history of humankind. By now the level of radiation has returned to the natural background almost everywhere, except for the worst contaminated territories.

The effects on flora and fauna were noticeable only in the immediate vicinity of the Chernobyl NPP, within the exclusion zone.

The paradigm of radioecology is this: if humans are protected well enough, the environment’s protection has multiple redundancy. If the influence of a radiation incident on human health is minimal, its effects on nature will be still less. The point where negative effects on flora and fauna begin to manifest themselves is a hundred times above the human body’s tolerance limit.

The accident’s influence on the environment after the accident was obvious only near the ruined reactor, where the trees’ exposure measured 2,000 roentgens over just two weeks (the so-called Red Forest). The environment has now fully recovered and began to thrive, as the anthropogenic influences on it have eased.

Delusion 4. The resettlement of residents from the town of Pripyat and the adjoining areas was poorly organized

The evacuation of Pripyat, which at that moment had a population of 50,000, was fast and timely, Arutyunian says.  Although by the rules effective at that moment evacuation was mandatory only after the dose reached 750 millisieverts, the decision in favor of evacuation was made when the forecast level was still under 250 millisieverts. Which quite agrees with today’s understanding of criteria for urgent evacuation. All claims to the effect the people then suffered serious exposure to radiation while being evacuated are not true, says Arutyunian.

Delusion 5. The authorities concealed the truth from the population and the public from the very first minutes of the Chernobyl disaster while knowing well enough what was going on.

It was all far more complicated, Arutyunian believes. True, the authorities did conceal some information, but first and foremost, the system itself proved unable to assess the situation quickly and properly.

The country lacked a reliable, let alone independent system of radiation situation control encompassing vast territories outside the premises of nuclear power plants. There was no chance of gathering information about the radiation level on vast territories that suffered from radioactive fallout.

Had such a system been in place by that time, it would be possible to prevent people from using locally-grown and made foods and to forestall the remote effects, such as thyroid gland cancer. Initially, the authorities were unaware of what had happened and what the real situation was.

By now all monitoring facilities around nuclear power plants have been equipped with computerized system of radiation situation control that enables the authorities and even any individual to see the situation around NPPS and other radiation-risky nuclear industry enterprises.

Delusion 6. Nuclear power as such is to blame because it cannot be controlled

Above all it should be remembered, Arutyunian remarks, that Chernobyl personnel had violated all instructions and rules while staging a series of tests and experiments.

This explains why several years would be spent on enhancing not so much the safety systems as such, as on the systems of safety involving the so-called “human factor.”

Secondly, the decision to hand over nuclear power plants to the Soviet Union’s Ministry of Energy had been a mistake. Practically all basics of safety culture in the nuclear power industry had been ignored. The Energy Ministry’s personnel were not trained well enough for operating nuclear power plants.

These days NPP personnel in all their actions strictly follow the internationally recognized approaches and documents. The condition and safety parameters of each reactor at each NPP are monitored technically in the on-line mode. The data are transmitted to the crisis management center of the nuclear power concern Rosenergoatom. This ensures continued control of the reactors’ safety parameters irrespective of the power plants’ personnel.

After the 1979 Three Mile Island incident in Pennsylvania (considered the worst before 1986) and the Chernobyl disaster all safety requirements, in particular, approaches to designing, building and operating nuclear power plants, underwent fundamental revision around the world. These days multiple redundancy protection and safety systems account for up to 40% of the NPPs’ costs.

All releases and dumping of radioactive substances that accompany the NPPs’ operation are within strictly determined limits. They are set at levels 50%-60% below those that have been found harmful to human health, let alone the environment.

Nuclear power is developing. Ten leading countries account for 80% of NPP-generated electricity, Arutyunian says. The United States operates 100 reactors, and Western Europe, 140. Large-scale nuclear power development programs have been adopted in the industrialized countries. The Fukushima nuclear power plant disaster of March 2011 has had practically no effects on the scale of nuclear power development programs.

 

Prepared by: Maria Smetannikova, Elizaveta Tsaritsyna, Valery Korneyev, Sergey Mazayev

Photos: Daniel Berehulak, Sean Gallup/Getty Images

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