By John Hallam
The most radioactive real estate in the world is located near Chelyabinsk in the southern Urals. Five plutonium production reactors there were closed down last year.
During the early phases of Soviet warhead production from 1948 to 1951, high level waste was dumped directly into the river Techa. This practice was stopped in 1951, when radioactivity was picked up in the Arctic Ocean.
Waste was then dumped directly into Lake Karachay — actually a swamp — where it accumulated and concentrated. Eventually, Karachay's 100 acres contained 120 million curies of radioactivity, 2.5 times the total released from Chernobyl and including long-lived isotopes strontium-90 and caesium-137.
According to a report by Thomas Cochran of the US Natural Resources Defense Council, "On the lake shore, in the region near the discharge line, the radiation exposure is about 600 roentgens per hour, sufficient to kill a person in an hour."
The grand total of radiation released by Chelyabinsk 40, however, is now calculated at an astonishing 1 billion curies between 1948 and 1960 — 20 times the Chernobyl release. This includes the 120 million curies dumped into Karachay, and 2.5 million curies released in a 1957 explosion of waste storage tanks when cooling systems failed, known as the Kyshtym disaster.
There are two further radiological problems associated with the Chelyabinsk 40 complex: the dispersal of radioactive dust from the banks of Karachay and the disposal of solid radioactive waste at the reactor site.
The Soviet government has been trying to fill in and immobilise Lake Karachay since 1967. It is difficult work involving heavily shielded machinery, and is planned for completion by 1995. A further system of "engineered barriers" to prevent the migration of highly contaminated ground water is supposed to be complete by the year 2000.
According to health physicist Alexander Shylyakter, workers at Chelyabinsk 40 received on occasion over 100 rem during the 1940s and '50s. Their collective dose may have been more than that to Japanese civilians as a result of Hiroshima and Nagasaki.
This record raises some worrying prospects for the immediate future: as the USSR fragments, what will become of the Soviet nuclear power industry?
In spite of Chernobyl, in December 1990 the USSR was the third largest operator of nuclear power plants in the world. (The US had 111 operating nuclear plants and a net capacity of 99,500 MWe, followed by France, with 53 reactors and 52,000 MWe, and then the USSR with 46 reactors and 34,302 net MWe.)
Who will inherit all the reactors, enrichment plants, reprocessing c etc?
Russia will be the main "beneficiary", as one would expect from its size, but there will be some unexpected results.
The two largest reactors in the world, the monster 1500 MWe RBMK plants at Ignalina, will become part of the infrastructure of Lithuania. Ignalina 1 & 2 are "second generation" graphite moderated, water cooled plants similar in design to that at Chernobyl, but with a much higher "power density". Its designers insist that the plant's greater power density gives it more forgiving properties than Chernobyl had, and that it does not have the "negative void coefficient of reactivity" that sent Chernobyl out of control. It is also supposed to have a superior emergency shutdown system.
Lithuanian politicians have been unable to decide whether Ignalina has been run with reckless disregard for safety, or perversely throttled back to destroy the Lithuanian economy.
In 1989, Lithuanians were saying that the plant was dangerous at full power because the graphite core was gradually swelling under neutron bombardment.
But by June 1990 they were accusing Moscow of trying to destroy their economy by throttling the reactors back to 1250 MWe for safety reasons. The earlier generation 1000 MWe RBMK plants had at the time been cut back to 700 MWe.
Another big inheritor will be the Ukraine. It will get all the Chernobyl RBMK plants, together with the exclusion
zone, the crumbling sarcophagus, 12 operating VVER reactors of 440 MWe and 1000 MWe size and five reactors under construction.
Russia inherits 28 operating reactors, of which 11 are RBMK-1000 plants, three are very ancient plutonium production reactors located at Chelyabinsk (Troitsk D, E and F), and one is a 600 MWe fast breeder located at Beloyarsk, close to Chelyabinsk. Russia also inherits a lot of decommissioned plants, notably Troitsk A, B and C, and Beloyarsk 1 & 2 near Boris Yeltsin's home town of Sverdlovsk.
Kazakhstan will get its very own ageing fast breeder reactor. The Armenians will inherit two decommissioned 440 MWe VVER plants. There is talk of reviving these plants, but no consensus on whether, or how, to do so.
Chernobyl's legacy
Since Chernobyl exploded five years ago, there has been a 10-fold rise in the number of operations for thyroid cancer in children in Kiev, and a tripling of child leukaemia rates in Byelorussia.
Ukrainian physicist Victor Chernousenko estimates the number of deaths to date amongst Chernobyl clean-up personnel at 5-7000. According to Chernousenko, of the 5000 most heavily irradiated workers, 80% have already died of radiation-related injuries.
According to the Chernobyl Union, about 5 million Soviet people have been affected by the disaster. Chernobyl Union's Robert Tilles says there will be a "significant increase" in leukaemia and other forms three to four years amongst the affected populations, and that the USSR simply isn't prepared to cope.
Tilles said it is incorrect to attribute cancers alone to of Chernobyl, adding to the list anaemia, fatigue and cardiovascular illness. "About 80% of the mitigators [clean-up personnel] we know of have five or six diseases now. You cannot reduce the question to just cancer or no cancer."
Tilles himself accumulated an official dose of 29 rem while pouring concrete for the sarcophagus, but he had already worked for two weeks with no dosimeter.
There is even now disagreement about the actual cause of the accident. The conventional wisdom has been that the plant operators broke every rule in the book in an almost wilful disabling of plant safety systems.
But the plant operators themselves tell a very different story. In a lengthy letter to the International Atomic Energy Agency safety advisory group INSAG, Anatolij Dyatlov, the plant manager in charge on the fateful night, pointed out that plant operators were misinformed — indeed, had been lied to — about the positive void reactivity coefficient, while they were also not told that graphite "followers" attached to the control rods of the emergency shutdown system would cause the plant to go critical and explode instead of shutting down when the scram button was pressed — not quite the sort of thing you expect to achieve when you press the scram button.
In the words of the former plant deputy manager: "An emergency situation — precisely when emergency protection is needed — puts the protection system out of action, and what is more, turns it into a device that drives the reactor out of control. This is, truly, a universal emergency protection system!"
Dyatlov wrote that reactor operators faced an impossible task: "In controlling the reactor, an operator performs more than a thousand manipulations in an hour, monitors more than four thousand parameters, and has to keep an eye on the parameter which, should it deviate, would explode the reactor. In doing so he must cope with:
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- The absence of any warning or emergency signalling system.
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- The absence of any instrument for monitoring the most vital parameter.
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- The fact that the parameter takes five minutes to measure, but can change in 20 seconds.
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- The fact that he lacks all knowledge of the evil properties of this parameter."
Official attitudes are increasingly inclined to see flaws in the reactor design — particularly in the emergency shutdown system. Prior to the August coup, a special commission of the Supreme Soviet was scheduled to publish the results of an inquiry according to which the main causes of the accident were: "Insufficient quality of g inadequate control and reactor protection systems accompanied by inadequate regulations."
A more pressing problem for the Soviet nuclear industry seems to be the fate of its PWR (VVER) plants. The Ukraine has 12 VVER plants, and Russia has 13, of which six are the suspect 365 MWe and 440 MWe models whose safety is open to question not only in the USSR, but in Germany (which has decided to decommission them permanently), in Czechoslovakia, which has embarked on a costly upgrading program, and in Bulgaria, which has recently shut its down.
In the USSR, Rovno 1 & 2 in the Ukraine have been shut down permanently, as have Armenia 1 & 2.
The problems afflicting the older generation of VVERs include neutron embrittlement of the reactor pressure vessel due to the nature of the metal, insufficient "redundancy" among reactor safety systems, leakage in safety confinement systems, obsolete control systems, lack of an auxiliary control room and susceptibility to "common mode" failures.
Prior to the closure of the Armenian VVERs in 1989, a plan to refit safety systems to those plants had been suggested, including the provision of independent emergency core cooling systems, independent emergency backup power supplies and extra accident confinement systems. This plan was abandoned when it became evident that it was going to cost more than the station had cost to build in the first place.
However, a "three-phase" plan to refit other VVER plants has now been adopted.
An interesting feature has been the keenness of Western governments to help — and even to apply heavy pressure to "fix" the problem. There seems to be far more mileage in getting the Soviets to fix their reactors than there is in fixing problems at, say, ageing US reactors, where operators are dragging their feet over some of the very same problems — notably vessel embrittlement.
The US Institute for Nuclear Power Operations has undertaken to apply the "lessons learned" from Three Mile Island at the Novovoronezh 1-5 plants. US utilities resisted implementation of the TMI "lessons learned" recommendations for years.
According to an INPO spokesperson: "If they have a major accident, it will affect our own nuclear program ... If we felt their reactors could not operate safely, we would advocate shutting them down. We have real reservations about fixing the older model reactors. The newer reactors have much more safety built in."
Western concern about Soviet reactor problems is at least in part self-interested. Firms such as Germany's Siemens have profitable refitting contracts in the USSR and its successor states, while governments are clearly concerned about the possibility of another Chernobyl.
According to German minister for environment and nuclear safety Klaus Toepfer, another serious accident at a Soviet or east European reactor would not only endanger Western nuclear programs, but would lead to ation" in eastern Europe.
Meanwhile, in the US, Senator Bennett Johnston has told President Bush: "Chances of an accident involving such reactors in the Soviet Union and Eastern Europe range from bad to hysterically bad ... Another Chernobyl or similar accident would doom the nuclear energy option."
John Hallam is uranium researcher for Friends of the Earth, Sydney.