The initial request that I should visit the Medzamor reactor and make a report thereon came in a letter from Mr Levon Ter- Petrossian, President of the Republic of Armenia in a letter to me of March 1992. This arose out of discussions with Dr Elena Bonner, Chairman of the Board of the Andrei Sakharov Foundation. The mission did not seem appropriate at that time. But an opportunity arose when the European Bank for Reconstruction and Development sent an expert team to investigate the state of readiness of the unit number 2 of the power plant and make a confidential report thereon to the Board of the European Bank. I accompanied them on this visit and make this separate report to the Andrei Sakharov Foundation, and through them to the President of Armenia.
Considerable advantages accrued to my joining this expert team. Firstly I know the members personally and have discussed reactor safety frequently with them and in particular have discussed safety of the reactors designed in the USSR. This enabled me to be aware of issues that otherwise I might have missed. Secondly the Armenian government had ensured that there were available to us all the most important people connected with the plant recommissioning and operation, enabling me to make enquiries and gain impressions which otherwise would not have been possible. I am grateful to the European Bank and to my colleagues for allowing me to accompany them on this visit. Although I believe that much, if not all, that is said in this report will find agreement among these experts, I have written this report independently and they are in no way responsible for the opinions presented herein.
I am particularly grateful to the Deputy Prime Minister Mr Chichechian for welcoming me (and my wife who accompanied me) to Armenia as a part of the team.
According to the records of the International Atomic Energy Agency (IAEA) the Medzamor nuclear power plants were begun in 1973 and began commercial operation in 1979 and 1980 respectively. In 1982 one unit was damaged in a fire, although no dangerous radioactivity escaped. After that fire, extensive modifications were made to the plant to make it more secure against fire, and it was reported by the IAEA that it was the best protected against fire of all the VVER 440/230 reactors. In 1988, Armenia suffered a severe earthquake which caused extensive damage to nearby cities, although the nuclear power plant was undamaged. Nonetheless, according to reports at the time, the central committee of the Communist party worried about the Medzamor plant immediately, as did many others. Three ethnic Armenian engineers from Bechtel Corporation of San Francisco, USA, visited the plant and made recommendations to improve the earthquake resistance of auxiliary equipment. After consideration of these and other matters, it was decided in Moscow, with the approval of Yerevan authorities, to shut the plant down. This decision seemed sensible to them at the time, but geopolitical considerations make it seem less sensible in retrospect.
Armenia has few indigenous fuel resources. In 1988 the electrical generating capacity was about 3,500 MW(e) made up of 900 Mw(e) nuclear, 1,750 MW(e) fossil fuel generators, and 900 MW(e) hydropower, mostly from Lake Sevan. In 1995, fuel shortages limit the fossil fuel capacity to only 500 MW(e), and ecological considerations limit the hydropower from Lake Sevan to 400 MW(e) for a total of 900 MW(e). There are few other hydroelectric resources. Electricity is cut off to residential customers on a rotating basis, and there is limited electricity even to run pumps to supply water to the population.
In 1989, it was anticipated that Armenian energy policy could be part of a regional Caucasian energy policy. There is plentiful, moderately priced, natural gas in Turkmenistan, with an adequate pipe line through Azerbaijan. The electricity grid of the USSR seemed adequate and could be extended. In 1991 this changed. The civil war in Nogorny Karabagh led Azerbaijan and Turkey to lay an economic and fuel embargo on Armenia and there is no sign that it will be lifted soon.
Fuel embargoes have been seen before in the world. Japan joined Russia, Great Britain and France in the Great War of 1914 to gain control of Manchurian coal which had been a German concession, and attacked Pearl Harbor in 1941 because of the oil embargo placed on Japan by Holland and the United States. History tells us that a country which has an inadequate fuel supply can be a desperate and dangerous country. Therefore it is important for peace in the Caucasus, and hence the world, that Armenia should have a degree of short term energy independence even if the present embargo is lifted. This leads to the conclusion that nuclear power for Armenia is essential both in the short term and in the long term. Armenia wishes not only to restart the Medzamor plant as soon as possible, but to build new facilities to replace, and perhaps increase, them. We were told orally that the Medzamor plant will operate only seven more years, but this is clearly a matter of desire rather than of detailed planning. There is some plan for a replacement about 2005 but this will clearly need considerable investment. No sensible alternative to nuclear power, and to the temporary operation of the Medzamor plant has been suggested by anyone. These two reasons, humanitarian aid to the Armenian people and help in securing the peace of the world were both of great interest to Andrei Dmitreyvich Sakharov during his last years, and are therefore both important to the Andrei Sakharov Foundation. However the power plants must be made as safe as reasonably possible. This visit was to report on the efforts of the Armenians to this end.
Everyone agrees that the decisions about energy policy in Armenia and nuclear power in particular must now be made by the Armenians themselves. This includes scientists, engineers and politicians in Russia as well as western scientists. However Russia and other countries can help. The government of Armenia decided in 1993, with an official start in February 1994, to restart the Medzamor power plant. The electricity shortages might have suggested an immediate restart, but the decision was made to check every piece of equipment as if the plant was being started for the first time, and to add all the safety precautions that the best engineers and scientists in the world could suggest. Specifically, it is to be as safe as any other power plant of this type. This has entailed detailed work for the last 18 months, and the results of much of this work are now visible. In this work the help of Russian engineers, and financial aid from the government of the Russian federation , has been essential and is much appreciated by all Armenians. This work is expected to be finished by October for a possible restart on November 1st in time to help allay the fuel shortages in the forthcoming winter. However, the decision has been made to make safety an overriding priority so that if all the additional safety features are not ready at this time restart will be postponed.
The Medzamor reactors are of the pressurized water type and are designated VVER 440/270. They are a slight improvement over the VVER 440/230 (they have additional pumps for decay heat removal in the event of a severe earthquake) but the improvements are not as great as those the VVER 440/213. There are 10 reactors of this type operating in NuovoVoronezh and Tula in Russia, Kozloduy in Bulgaria, and Bohunice in Slovakia. Five plants in Greifswald, East Germany, were shut down soon after German reunification. These pressurized water reactors are very different from the RBMK reactors of which one exploded at Chernobyl and more similar to western reactors. But they are still an old type which would not be licensable in western Europe or the USA. Several reactors of a slightly improved type, VVER 440/213 are also operating in Russia and Eastern Europe. As of 1989, all of the VVER 440/230s possessed the following major deficiencies:
Politicians and professional engineers and scientists in the west have argued that all the VVER 440/230s should be shut down as soon as practicable and replaced by superior designs. However the countries of western Europe have accepted that economic considerations in the various countries of eastern Europe do not allow an immediate shut down. Recognizing the vital importance of safety to the whole world, western (primarily European) countries have supplied economic assistance to the countries of eastern Europe to make interim safety improvements. Armenia has decided to improve the safety level to the PRESENT level at all other VVER 440/230 reactors rather than the level of 1988. Nonetheless, the restart of a reactor already shut down seems contrary to the principle of phasing out the older reactors. The decision to restart attracts especial attention from the rest of the world and financial help from western Europe has not, therefore been supplied to Armenia.
It is not the purpose of this report to describe in detail the safety analyses and deficiencies of this type. Nor to describe in detail the particular Armenian reactors. There are several reports describing the Armenian from Bechtel corporation in USA, Kurchatov Institute and MINATOM in Russia, Framatome in France, the World Association of Nuclear Operators (WANO) and the International Atomic Energy Agency (IAEA). However, a few general observations may be useful.
A pressurized water reactor needs a good reactor vessel in which the reactor and its coolant water are placed under pressure. This vessel will inevitably be irradiated with fast neutrons from the nuclear fission and this will make the vessel, and any welds, somewhat more brittle. The early Russian built reactor vessels were particularly bad in this regard, but the Russians developed techniques of measuring the brittleness of the welds and of annealing them. Tests on the vessel on unit 2 suggest that it will be safe for 10 to 20 more years.
The primary safety concern with pressurized water reactors is that the heat be removed from the reactor core at all times. Even after shut down of the nuclear reaction there is decay heat that must be removed. There are several possible causes (initiators) of trouble. If there is a fire or earthquake that shuts down the reactor, disconnects it from the electricity grid, and also prevents the start of emergency pumps, the reactor will heat up. With reactors in the USA fuel can start to melt (as it did at Three Mile Island in 1989) within a couple of hours. However, in the VVER 440 series, the reactor can be isolated for at least 8 hours before problems begin. This time can enable the staff to recover damaged equipment and regain control. This was proven in the 1982 fire at Medzamor and at other VVER 440/230 reactors. This provides an inherent degree of safety that was not initially realized by many scientists and engineers in the west. Nonetheless the auxiliary equipment must be fire and earthquake resistant.
The initial inadequate resistance of this and other VVER 440 reactors to earthquake before 1990 can be illustrated by two deficiencies. Relays and other control equipment are operated by emergency DC power provided by a set of batteries that are continually recharged. Before 1990 these were lead-acid accumulators in glass jars, connected in series. If just one of these had shattered in an earthquake there would have been no DC power. In 1995 these glass batteries have been replaced by a more robust set of batteries bought in Germany.
If the steam turbines fail in an earthquake, and the cooling towers fall down, they cannot remove heat from the reactor. In 1988 there would be nothing to prevent ultimate melting of the reactor core. Now a cooling pond is being installed that will remain intact in a severe earthquake and which has adequate capacity to cope with the shut down heat. The Medzamor reactors will not restart until this cooling pond is finished.
The fire resistance has been much upgraded. 70 km of new control cable has been installed and the routing of these cables adjusted to assure independence of control in the event of fire. I saw many fire extinguishers which were absent in many Soviet laboratories and these seemed to be in working order.
There is one small detail that gives me small pause. The floor of many of the passageways is covered with plastic. This is a feature common to many Soviet reactors and laboratories. I was unable to discern whether the plastic is fire resistant or whether it has been tested. I remember that in describing the Chernobyl accident the General in charge of the fire brigade described in great detail the presence of materials that were supposed to be non-inflammable but nonetheless burnt merrily.
It has been suggested that the power plant is unusually attractive for a saboteur or terrorist from an unfriendly country, and that this possibility is, in itself, a reason for refraining from operation. In western plants the containment vessel protects many parts of the plant from attack by a mortar shell. The VVER 440/230 reactors have no containment and are therefore a little more vulnerable. However, an attack is more likely to come from a neighbor than from a distant country, and although the neighbor would be far less affected by any radioactivity release than Armenia itself, the possibility of adverse effects is likely to deter such action. I have found no reactor expert that considers this to be a serious threat.
One small issue deserves mention. In considerations of reactor safety, the probability of a direct hit by a falling aircraft is often as great as the probability of other accidents. Again this would be worse if there is no containment. This probability is increased when the reactor is near an airport as it is at Yerevan. It is increased still further if, as sometimes occurs with other landmarks, the reactor is used as a visual guidance point for incoming aircraft. ("Proceed until you see the reactor, turn left and you are in line with the runway"). I suggest that Armenian Airlines and airport authorities be warned against this common practice.
Although western experts did not agree with the Russian emphasis on operator error as the principal cause of the Chernobyl nuclear power accident they did agree that a professional approach to operation is essential. The most important is the establishment of what is called a "safety culture".
Every operator and staff member must think about safety in all his actions, and must know that his supervisor will encourage and support him in safety actions. This is particularly hard in those societies, such as the USSR, India and China, where safety has not been a feature of everyday life. This has been very evident in my many visits to the USSR and was even emphasized in my travel from Armenia to Moscow on Armenian airlines after this visit to Medzamor. Most of the passengers ignored the seat belts provided, and the belts in my seat had clearly not been used for some time. Although an announcement was made, (a small improvement from my first travel on Aeroflot in 1959) no effort was made by the cabin staff to ensure that everyone sat down during take off and taxiing. Fire is a frequent initiator of accidents in all technologies, and creates all encompassing and common mode failures. Smoking is forbidden in all western nuclear power plants and comparable industrial facilities. Yet smoking among operators was frequent when western expects first visited Bulgarian and other eastern European plants. Therefore I, as did the European Bank team, paid especial attention to the safety culture.
An important issue in reactor operation in a small country is a decision on the language in which everything is discussed. The Armenians have decided that it will be Russian. This seems a wise decision: most Armenians speak Russian, because of the two centuries of close association, and Armenia has need of Russian consultants especially those who designed this type of reactor. Armenia has joined the World Association of Nuclear Operators (WANO) which has an eastern European office in Moscow at the Institute for Nuclear Power Operations. There is a special radiotelephone link with this WANO office. This will keep Armenia in touch with the operators of other power plants of the same type. Armenia has now a Department of Regulation that is independent of the government, and exists to check every detail of the plant safety.
Although the USA, in common with other G7 countries, formally opposes the operation of these power plants, it is helping with regulation. The Office of International Programs of the US Nuclear Regulatory Commission has used some funds provided by the Agency for International Development (AID) to help them. This has included training in fire protection, and a grant of $100,000 this year. The Armenian Regulatory authority plan to use this money to pay for consultants from Russia who understand this type of plant. Obviously this new regulatory authority has difficulty in finding competent staff. But they have overlooked one important source of help. The Yerevan Physical Institute was founded by a great Armenian Physicist Artem Isaacovich Alikahanian, and their very competent scientists may be able to help. It is noteworthy that a street is named for the brothers Alikhanian. The other brother (who used the name Alikhanov) had helped in the design of the VVER 440 reactors when head of the Institute of Experimental and Theoretical Physics (ITEP) in Moscow. Although the greatest need is for persons with operating experience, intelligent physicists have easily learned, and led in the understanding of the important features of reactor safety.p In the USA this is evidenced, for example, by the work of Drs Rasmussen, Koutz and Budnitz. (In my first lecture at the Yerevan Physical Institute in 1965, I reported on the work of the graduate student Mr Budnitz who as Dr Budnitz was now on the European Bank team). Armenia should not overlook this reservoir of talent.
It is clear to me that everyone we met in Armenia from the President downwards is committed to the concept of a Safety Culture. My colleagues from the European Bank commented favorably on this to our Armenian hosts, and said that it was as good a response as they had in any of the eastern European reactors that they had visited. My personal observation, from more limited experience, is that the safety response of the top management is somewhat superior to that I have encountered in the USA and as good as I encountered in my official review of the three power plants in Taiwan. The staff were friendly, frank, open and professional in their response to detailed questions. The reactor and its auxiliary equipment were clean, passage ways were not blocked, and I saw no sign of the tell-tale cigarette butts that can show whether the dictates of management are in fact carried out.
The report of WANO was somewhat critical of the training of the operators. I believe that this has been corrected to a large extent. There are now enough trained operators to operate five shifts - three shifts per day plus weekends. This should be adequate. 75% of the operators have had previous experience with reactors of this type, either in Armenia several years ago, or at NuovoVoronezh. Other younger men are being trained in the simulator at NuovoVoronezh. This simulator is NOT a "full-scope"` simulator as is in use in western power plants but is adequate for training in ordinary operations and malfunctions. I also note that IAEA will assemble a group to test the readiness of the plant operating staff.
The first few days and weeks of any new operation are critical. It is then that surprises may occur and critical decisions may need to be made. The Armenians have been lucky to secure the services of Dr Gorbenko from the Kurchatov Institute in Moscow, who is perhaps the most experienced person in start up of these plants and was present at the start up of the Medzamor plants twenty years ago. In this connection it is important to realize that although the regulatory authority is independent of the power company, both are dependent on the government of Armenia. It is possible that a problem will arise during the initial commissioning which will require a difficult decision: should the start up be delayed a few months to complete some repair? or should it be started with less safety margin to ensure adequate electricity for the winter? Ultimately if this eventuality occurs it must be a decision for the President. It would be well if he selects his personal advisers in advance.
It is easier to make sensible suggestions for past actions than for future actions. I make the comments that follow, not to criticize those who made the best decisions that they knew how at the time, but to lay a foundation for better decisions in the future.
In 1989, after the realization that the Medzamor reactors were not as safe as desirable, there were two other good alternatives that were not followed. Each could have provided the Armenian people with better protection against the energy embargo that followed. Firstly, the USSR could have decided in 1989 to keep the plant running but to institute immediate safety improvements along the lines suggested by Hadjian's mission. Most of these improvements could have been made while the plant was operating or during a normal maintenance shut down. Then by 1991, when the embargo occurred, there would have been two safe reactors in operation. Secondly, but with far greater expense, steps could have been taken beginning in 1989, to commence the construction of a replacement. This would by now be well under way.
I believe that the Armenian engineers and scientists have done an excellent job so far in their preparation for restart of the nuclear power plant at Medzamor. There have been several reviews from international teams, and the Armenians have listened to their comments and made appropriate changes and safety improvements. Further safety improvements are expected on a continuous basis.
No technology is ever perfect, and every natural phenomenon also poses its hazards. The Medzamor reactor was, and will be, no exception. While many of the safety deficiencies noted above have been or will be eliminated, one remains. There is no containment vessel. Moreover although there will be considerable resistance to earthquake, it will not be as great as suggested by modern design criteria: that the reactor and crucial auxiliary equipment remain intact in the event of an earthquake that recurs every 10,000 years. It will only be assured that it will be intact in a 1000 year earthquake. But we must retain perspective. That the reactor is not intact does not mean an accident the size of Chernobyl. Moreover such an earthquake would be much bigger than the one in 1988 and would also destroy Yerevan and most of Armenia. There are other hazards of everyday life that are considerably greater. For example many experts believe that the impact of fossil fuel burning, through air pollution, on the citizens of the Commonwealth of Independent States, is every year as great as the one event of Chernobyl. The danger to the Armenian people of the present economic stagnation makes all these pale in comparison.
For all of these reasons therefore, I believe that the Armenian people can accept the renewed operation of the Medzamor power plant with confidence. However I recommend that as soon as the power plant is operative, and a normal situation of electricity supply is once again assured, that Armenia make prudent plans for replacement of the power plant with a more modern, safer, power plant that meets international standards.
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