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Atomic Incidents

The welding seams have become a little brittle over the years. In 1985, this would have almost led to a disaster at the nuclear power plant of Bohunice.



Cooling towers of a WWER1000 atomic power plant in Czech Temelin with a Greenpeace protest banner
Picture by T. Micke

Is nuclear energy really as clean as some proponents claim? Is a nuclear power plant in normal operation really harmless? Each reactor releases radioactive radiation into the environment. Some types like the WWER-440 (four of them are in use at Bohunice) are actually as dangerous as ticking time bombs.

The plant of Bohunice has got a long and disastrous history. In 1958 the Communist Party and president Antonin Novotny were in power. They began the construction of the "A1" – an atomic reactor of the Czechoslovakian Skoda plant. According to the International Atomic Energy Agency (IAEA) the construction took nine years – that's a pretty long time for a tiny plant with a net achievement of 103 MW.

The A1 was in use for not even six and a half years. Then it had to be shut down for "technical reasons". Two severe accidents had been the cause for this decision:

On the 5th of January 1976, highly radioactive gas leaked from the reactor room. Two technicians died. They couldn't save themselves in time because the emergency exits were locked. For years to come crops and grass were contaminated.

A year later on February 24th technicians assembled the reactor with new fuel rods. They forgot some packaging material in the pressure vessel, which caused the fuel rods to overheat. The result was a core meltdown. Loads of radiation (4000 Becquerel) was released into the environment together with water vapor. At some spots of the river Dudvßh a radioactive contamination was measured as bad as 3 days after the nuclear accident at Chernobyl. According to the officials, the amount of radiation the population in the surroundings of the plant was exposed to be "harmless".

The reactor and the fuel rods were badly damaged. The reactor had to be shut down in 1979. Until this day, highly radioactive material remains buried beneath the ruins of the reactor. They may not be manipulated because of the strong corrosion and their fragility. Radiation is still leaking into the environment from the permeable building. The A4 requires a professional tear-off but the government keeps on postponing it.


In 1974, Czechoslovakia began building two "V1" reactors. In 1976, followed two updated "V2" reactors. The four units (type WWER 440) are in use.

The technicians of the "V1" made the mistake of thinking that a nuclear accident in the primary circle is impossible. That is why the "V1" doesn't have a "containment" – a protective shielding that can bear high pressures. Therefore the plant would not be able to withstand excess pressure of radioactive steam if some pipes were to break.

The German company "Siemens/KWU" explained to the Czechoslovakian ministry of economics that the entire control and safety system was dangerous and needed replacement.

This was confirmed by two reports of the Czechoslovakian Atomic Commission in 1989 and by two accidents in 1991. On the 20th of Mai and the 2nd of July the isolation of some very important electric cables was damaged due to a short circuit. As a result one of the water pumps stopped working. The personnel reacted quickly and that's why severe consequences could be avoided. However the Czechoslovakian commission categorized this "mishap" as "significant for the safety" of the reactor.

The commission also criticized the leakiness of the steam generator. There had been a leakage of radioactivity several times over the years in spite of reparations. This is a common flaw of all of the WWER-440 reactors, no matter if they are old or new.

On top of that the pressure vessel is too old and unsafe. The welding seams close to the reactor core have become brittle and sensitive to temperature changes over the years. This happens especially in most of the older reactors because of the neutron radiation and the contamination. According to the physician Prof. Dr. Manfred Heindler, chairman of the Austrian Atomic Commission in Bohunice, these circumstances would have almost led to a catastrophe in 1985.

Due to a mistake in the control center cold water came onto the extremely hot reaction core. The welding seams almost broke because of this sudden temperature change. The technicians just managed to keep the pressure vessel from bursting. Dr.Heindler: "It can happen again! At any time! The welding seams are getting more fragile each year!"

In future we should give more thought to where the electric power in our power plugs comes from
T. Micke

In the beginning of the year there were fires in the power distributor and the switching system due to electric defects. The Czechoslovakian officials only informed the Austrian government 24 hours after the accident. Their argument: "There was no leakage. According to the atomic treaty between Austria and Czechoslovakia the population only has to be informed if there was leakage. And even that isn't obligatory."

In the treaty it is written: "The content of the received information from the other party may be used to inform the public unless the other party wants it to remain strictly confidential."

A Lawyer of "Greenpeace" Dr. Josef Unterweger: "It is an offense against the Convention of Human Rights. Besides, there are no sanctions mentioned in case one of the parties doesn't keep to the treaty. So actually nobody is obligated to stick to the treaty"

The Austrian government has mentioned that it mistrusts the Czechoslovakian government concerning the atomic treaty. Yet no steps were taken to improve the treaty.


< Read part 11 of the series: In the shade of the cooling towers

© A report by Tobias Micke (30-04-91) – Contact