In April 1983, I wrote an article on creeping planning in nuclear power construction and offered it to one of the mainstream newspapers. (Creeping planning is when, after the failure of one deadline for commissioning an object, a new deadline is repeatedly appointed without organizational conclusions regarding workers who have failed a government task. Time creep to the right often goes on for many years with a colossal excess of the estimated cost of construction.) The article was not adopted.
Here is a short excerpt from this unpublished article.
The atomic direction in energy construction was headed by 60-year-old Deputy Minister A. N Semyonov, who was only assigned to this difficult task three years ago, being a builder of hydroelectric power plants by education and many years of experience. It was only in January 1987 that he was removed from the leadership of the construction of nuclear power plants following the results of 1986 for disrupting the commissioning of power facilities.
The situation was not the best in the management of the operation of operating nuclear power plants, which on the eve of the catastrophe was carried out by the All-Union Industrial Association for Atomic Energy (abbreviated as VPO Soyuzatomenergo). Its chief was G. A. Veretennikov, who had never worked in the operation of a nuclear power plant. He did not know atomic technology and after 15 years of work in the USSR State Planning Committee decided to go for a living business (following the results of Chernobyl in July 1986, he was expelled from the party and removed from work) …
Already after the Chernobyl accident, B. Ye. Shcherbina from the rostrum of the expanded Collegium of the USSR Ministry of Energy in July 1986 said, addressing the power engineers sitting in the hall:
- All these years you went to Chernobyl! If this is so, then it should be added that Shcherbina and Mayorets accelerated the march towards the explosion …
Here I consider it necessary to interrupt in order to acquaint the reader with an excerpt from F. Olds' curious article "On Two Approaches to Nuclear Energy", published in Power Engineering magazine back in October 1979.
“… While the member countries of the Organization for Economic Co-operation and Development (OECD) face numerous difficulties in the implementation of their nuclear programs, the CMEA member countries have embarked on a joint plan that envisages an increase in the installed capacity of nuclear power plants by 1990 by 150,000 MW (this is more than one third of the current capacity of all nuclear power plants in the world). It is planned to commission 113,000 MW in the Soviet Union.
At the 30th Jubilee Session of the CMEA in June 1979, a joint program was developed. There seems to be some fear behind this determination to pursue plans for nuclear power development, caused by a possible shortage of oil in the future. The USSR supplies oil to the countries of Eastern Europe and, in addition, exports it to the West in the amount of 130 thousand tons per day. (It should be added here that as of 1986 the USSR pumps to the West 336 million tons of standard fuel per year - oil plus gas - GM) However, in 1978 the volume of oil production in the USSR did not reach the planned level. Apparently this will not happen in 1979. According to forecasts, the oil production plan is unlikely to be fulfilled in 1980 either. Everything suggests that the development of giant oil fields in Siberia is fraught with difficulties
Chairman of the Council of Ministers of the USSR A. N. Kosygin, in his speech at the jubilee session of the CMEA, noted that the development of nuclear power is the key to solving the energy problem.
There are reports that negotiations are underway between the USSR and the FRG on the export of equipment and technology to the USSR. Probably, this should contribute to the earliest possible solution of the nuclear program of the CMEA countries. (The negotiations were interrupted due to the unacceptable counter-conditions of the West German side - G. M.)
In early 1979, Romania signed a $ 20 million licensing agreement with Canada for the construction of four CANDU-type nuclear reactors with a unit capacity of 600 MW. It is reported that Cuba intends to build one or more nuclear power plants according to the Soviet design. Experts believe that this project does not provide for such mandatory structural elements in the West as a reactor containment shell and an additional core cooling system. (Here F. Olds was clearly mistaken. At the Cuban nuclear power plants being built according to Soviet projects, containment shells and additional cooling systems for the core are provided. - G. M.)
The USSR Academy of Sciences - this, however, was to be expected - assures the general public that Soviet nuclear reactors are absolutely reliable and that the consequences of the accident at the Threemile Island nuclear power plant are overly dramatized in the foreign press. The prominent Soviet atomic scientist AP Aleksandrov, President of the USSR Academy of Sciences and Director of the Kurchatov Institute of Atomic Energy, recently gave an interview to the London correspondent of the Washington Star newspaper. According to him, the failure to develop nuclear energy can have dire consequences for all of humanity.
A. P. Aleksandrov regrets that the United States used the incident at the Threemile Island nuclear power plant as an excuse to slow down the pace of further development of nuclear power. He is convinced that the world's oil and gas reserves will run out in 30-50 years, so it is necessary to build nuclear power plants in all parts of the world, otherwise military conflicts will inevitably arise due to the possession of the remnants of mineral fuel. He believes that these armed clashes will take place only between the capitalist countries, since by that time the USSR will be provided with an abundance of nuclear energy.
The SECD and CMEA Organizations - Acting in Opposite Directions
In the industrially developed countries of the world, two organizations, the SECD and the CMEA, have been created, which have huge oil reserves. It is curious that they have different attitudes towards the problem of future energy supply.
CMEA focuses on the development of nuclear energy and does not attach much importance to the prospects for the use of solar energy and other options for a gradual transition to alternative sources of energy supply. Thus, the GDR expects to meet its energy needs in the future from these sources by no more than 20 percent. Environmental issues are highlighted, but the foreground is increasing the productivity of equipment and raising the standard of living of the population.
The countries of the CECD have developed a number of their own programs for the development of nuclear power. France and Japan have achieved more in this respect than everyone else. The United States and the Federal Republic of Germany are still taking a wait and see attitude, Canada hesitates for many reasons, and other states are not particularly in a hurry to implement their programs.
For many years, the United States has led the CECD in both the practical use of nuclear energy and in terms of R&D funding. But then this situation changed quite quickly, and now the development of nuclear power is viewed in the United States not as a priority task of national importance, but only as an extreme means of solving the energy problem. The main focus in any discussion of any energy-related bill is environmental protection. Thus, the leading member countries of the CECD and CMEA take diametrically opposite positions in relation to the development of nuclear energy …"
The positions, of course, are not diametrically opposed, especially on issues related to improving the safety of nuclear power plants. F. Olds is inaccurate here. Both sides are paying maximum attention to this issue. There are also indisputable differences in assessments of the problem of the development of nuclear power.
- Excessive criticism and a clear overestimation of the danger of nuclear power plants in the United States;
- the complete absence of criticism for three and a half decades and the clearly underestimated danger of nuclear power plants for personnel and the environment in the USSR.
The clearly expressed conformism of the Soviet public, which recklessly believed the assurances of academicians and other incompetent figures, is also surprising.
Isn't that why Chernobyl fell on us like a bolt from the blue and plowed so many?
Plowed, but not all. Unfortunately, conformism and gullibility continue. Well, it's easier to believe than to question soberly. Less hassle at first …
At the 41st Session of the CMEA, which took place on November 4, 1986 in Bucharest, that is, seven years after the publication of F. Olds's article "On Two Approaches to Nuclear Energy", the Session participants again spoke confidently about the need for accelerated development of nuclear energy.
Chairman of the Council of Ministers of the USSR N. I. Ryzhkov in his report at this session, in particular, said:
“The tragedy in Chernobyl not only did not diminish the prospects of nuclear energy in cooperation, but, on the contrary, putting the issues of ensuring greater security in the center of attention, strengthens its importance as the only source that guarantees reliable energy supply for the future … The socialist countries are even more actively involved in international cooperation in this area, based on the proposals made by us to the IAEA. In addition, we will build nuclear heating plants, saving valuable and scarce fossil fuel - gas and fuel oil”.
It should be emphasized here that nuclear heat supply stations will be built in the suburban area of large cities, and special attention should be paid to the safety of these stations.
The energetic formulation of the question of the development of nuclear energy both in the USSR and in the CMEA countries forces us to comprehend the Chernobyl lesson even more closely, which is possible only in the case of an extremely truthful analysis of the causes, essence and consequences of the catastrophe experienced by all of us, all of mankind at the nuclear power plant in Belarus. Ukrainian Polesie. Let's try to do this by following day by day, hour by hour, how events developed during the pre-emergency and emergency days and nights.
2
April 25, 1986
On the eve of the disaster, I worked as deputy head of the main production department of the USSR Ministry of Energy for the construction of nuclear power plants.
On April 18, 1986, I went to the Crimean NPP under construction to inspect the progress of construction and installation work.
On April 25, 1986, at 4:50 pm (8, 5 hours before the explosion) I flew from Simferopol to Moscow on an IL-86 plane. I don’t recall any premonitions or worries about anything. During takeoff and landing, however, it was heavily smoked with kerosene. It was annoying. In flight, the air was perfectly clean. And only slightly disturbed by the continuous rattling of a poorly regulated elevator, which carried stewardesses and stewards with soft drinks up and down. There was a lot of hustle and bustle in their actions and they seemed to be doing unnecessary work.
We flew over Ukraine, drowning in blooming gardens. Some 7-8 hours will pass, and a new era will come for this land, the granary of our motherland, an era of trouble and nuclear filth.
In the meantime, I looked through the porthole at the ground. Kharkov floated in the bluish haze below. I remember regretting that Kiev was left on the sidelines. After all, there, 130 kilometers from the capital of Ukraine, in the seventies, I worked as a deputy chief engineer at the first power unit of the Chernobyl nuclear power plant, lived in the city of Pripyat on Lenin Street, in the first microdistrict most exposed to radioactive contamination after the explosion.
The Chernobyl nuclear power plant is located in the eastern part of a large region called the Belarusian-Ukrainian Polesie, on the banks of the Pripyat River, which flows into the Dnieper. The places are mostly flat, with a relatively flat relief, with a very slight slope of the surface towards the river and its tributaries.
The total length of the Pripyat before the confluence with the Dnieper is 748 kilometers, the width is about three hundred meters, the current speed is one and a half meters per second, the average long-term water consumption is 400 cubic meters per second. The catchment area at the site of the nuclear power plant is 106 thousand square kilometers. It is from this area that the radioactivity will go into the ground, and also be washed away by rains and melt water into the rivers …
The Pripyat river is good! The water in it is brownish, apparently, because it flows from the peat bogs of Polissya, is densely saturated with fatty acids, the current is powerful and fast. When bathing, it blows a lot. The body and hands are unusually tight; when rubbed with a hand, the skin creaks. I swam a lot in this water and a cellar on academic boats. Usually, after work, he came to the boathouse on the banks of the oxbow, took out the skiff alone and for two hours glided along the water surface of an ancient river, like Russia itself. The shores are quiet, sandy, overgrown with young pine trees, in the distance a railway bridge, across which the Khmelnitsky - Moscow passenger train rumbled at eight in the evening.
And the feeling of pristine silence and purity. Stop rowing, scoop up brownish water with your hand, and your palm will immediately pull away from fatty marsh acids, which later, after the explosion of the reactor and radioactive release, will become good coagulants - carriers of radioactive particles and fission fragments …
But let's return to the characteristics of the area where the Chernobyl nuclear power plant is located. This is important.
The aquifer, which is used for the economic water supply of the region under consideration, lies at a depth of 10-15 meters relative to the level of the Pripyat River and is separated from the Quaternary sediments by almost impermeable clay marls. This meant that the radioactivity, having reached this depth, would be carried horizontally by groundwater …
In the area of the Belarusian-Ukrainian Polesye, the population density is generally low. Before the construction of the Chernobyl nuclear power plant, it was about 70 people per square kilometer. On the eve of the disaster, about one hundred and ten thousand people lived in the 30-kilometer zone around the nuclear power plant, of which almost half - in the city of Pripyat, located to the west of the 3-kilometer sanitary zone of the nuclear power plant, and thirteen thousand - in the regional center of Chernobyl, in eighteen kilometers southeast of the nuclear power plant.
I often recalled this glorious town of nuclear power engineers. It was built with me almost from scratch. When I left for work in Moscow, three microdistricts were already populated. The town is cozy, comfortable to live in and very clean. One could often hear from visitors:
"What a beauty Pripyat!" Many retirees strove here and came to permanent residence. Sometimes with great difficulty, through government agencies and even the court, they sought the right to live in this paradise, combining beautiful nature and successful town-planning findings.
Quite recently, on March 25, 1986, I came to Pripyat to check the progress of work at the 5th power unit of the Chernobyl nuclear power plant under construction. All the same freshness of clean, heady air, all the same silence and comfort, now not a village, but cities with a population of fifty thousand …
Kiev and the Chernobyl nuclear power plant remained northwest of the flight route. Memories faded, and the huge cabin of the airliner became a reality. Two aisles, three rows of half-empty chairs. For some reason, the feeling that you are in a huge barn. And if you shout, it will backfire. Next to me is the constant rumble and clatter of the elevator scurrying back and forth. It seems that I am not flying in an airplane, but riding in a huge empty tarantass along a blue cobblestone road. And milk cans rattle in the trunk …
I got home from the Vnukovo airport by nine in the evening. Five hours before the explosion …
On the same day, April 25, 1986, the Chernobyl nuclear power plant was preparing to shutdown the 4th power unit for scheduled preventive maintenance.
During the shutdown of the unit for repairs, according to the program approved by the chief engineer N. M. Fomin, it was supposed to conduct tests (with the reactor protections turned off) in the mode of complete de-energization of the NPP equipment using the mechanical energy of the generator rotor run-out (inertial rotation) to generate electricity.
By the way, carrying out such an experiment was offered to many nuclear power plants, but because of the riskiness of the experiment, everyone refused. The leadership of the Chernobyl nuclear power plant agreed …
Why was such an experiment needed?
The fact is that in the event of a complete power outage of the equipment of a nuclear power plant, which can occur during operation, all mechanisms stop, including the pumps that pump cooling water through the core of the nuclear reactor. As a result, the core melts, which is tantamount to an ultimate nuclear accident.
The use of any possible sources of electricity in such cases provides for the experiment with the run-out of the rotor of the turbine generator. After all, while the rotor of the generator rotates, electricity is generated. It can and should be used in critical situations.
Similar tests, but only with the reactor protection included in the operation, were carried out earlier at other nuclear power plants. And everything went well. I also had to take part in them.
Usually the programs of such works are prepared in advance, agreed with the chief designer of the reactor, the general designer of the power plant, Gosatom-Energonadzor. In these cases, the program necessarily provides for a backup power supply to responsible consumers for the duration of the experiment. For the de-energization of the power plants' own needs during the tests is only implied, and does not actually occur.
In such cases, the auxiliary power supply from the power system must be connected through the working and starting-standby transformers, as well as autonomous power supply from two standby diesel generators …
To ensure nuclear safety during the testing period, the reactor emergency protection (emergency introduction of absorbing rods into the core), which is triggered when the design settings are exceeded, as well as an emergency cooling water supply system to the core should be in operation.
With the proper order of work and the adoption of additional safety measures, such tests at an operating NPP were not prohibited.
It should also be emphasized that tests with the generator rotor run-out should be carried out only after the emergency protection of the reactor (abbreviated AZ) has been triggered, that is, from the moment the AZ button is pressed. Before this, the reactor must be in a stable, controlled mode, having a routine operational reactivity margin.
The program, approved by the chief engineer of the Chernobyl NPP, N. M. Fomin, did not meet any of the listed requirements …
A few necessary explanations for the general reader.
A very simplified core of the RBMK reactor. is a cylinder with a diameter of about fourteen meters and a height of seven meters. Inside this cylinder is densely filled with graphite columns, each of which has a tubular channel. Nuclear fuel is loaded into these channels. From the end side, the cylinder of the core is uniformly penetrated by through holes (pipes), in which the control rods that absorb neutrons move. If all the rods are at the bottom (that is, within the core), the reactor is plugged. As the rods are removed, a chain reaction of nuclear fission begins, and the power of the reactor increases. The higher the rods are removed, the greater the reactor power.
When the reactor is loaded with fresh fuel, its reactivity margin (in short, the ability to increase the neutron power) exceeds the ability of the absorbing rods to damp the chain reaction. In this case, a part of the fuel cartridges is removed and fixed absorbing rods (they are called additional absorbers-DP) are inserted in their place, as if to help the moving rods. As the uranium burns out, these additional absorbers are removed and nuclear fuel is installed in their place.
However, an immutable rule remains: as the fuel burns out, the number of absorbing rods immersed in the core should not be less than twenty eight to thirty pieces (after the Chernobyl accident, this number was increased to seventy two), since at any time a situation may arise when the ability of the fuel to grow power will be greater than the absorption capacity of the control rods.
These twenty-eight to thirty rods, which are in the high-efficiency zone, constitute the operational reactivity margin. In other words, at all stages of reactor operation, its acceleration ability should not exceed the ability of the absorbing rods to drown out the chain reaction …
A short summary of the station itself. Unit 4 of the Chernobyl nuclear power plant was commissioned in December 1983. By the time the unit was shutdown for scheduled maintenance, which was scheduled for April 25, 1986, the nuclear reactor core contained 1,659 fuel assemblies (about two hundred tons of uranium dioxide), one additional absorber loaded into the process channel, and one unloaded process channel. The main part of the fuel assemblies (75 percent) were cassettes of the first load with a burnup depth close to the maximum values, which indicates the maximum amount of long-lived radionuclides in the core …
The tests, scheduled for April 25, 1986, had previously been carried out at this station. Then it was found that the voltage on the generator tires drops much earlier than the mechanical energy of the generator rotor is consumed during coasting. The planned tests provided for the use of a special regulator of the magnetic field of the generator, which was supposed to eliminate this drawback.
The question arises, why did the previous tests go without an emergency? The answer is simple: the reactor was in a stable, controlled state, the entire protection complex remained in operation.
But let us return to the working program for testing the turbine generator No. 8 of the Chernobyl nuclear power plant. The quality of the program, as I said, turned out to be low, the section on security measures provided for in it was drawn up purely formally. It only indicated that during the testing process, all switchings on the equipment are done with the permission of the unit shift supervisor, and in the event of an emergency, personnel must act in accordance with local instructions. Before the start of the tests, the head of the electrical part of the experiment, electrical engineer Gennady Petrovich Metlenko, who is not an employee of the nuclear power plant and a specialist in reactor installations, instructs the watch on duty.
In addition to the fact that the program essentially did not provide for additional safety measures, it prescribed the shutdown of the emergency reactor cooling system (abbreviated ECCS). This meant that during the entire scheduled testing period, that is, about four hours, the safety of the reactor would be significantly reduced.
Due to the fact that the safety of these tests was not given due attention in the program, the personnel were not ready for the tests, they did not know about the possible danger.
In addition, as will be seen from what follows, the NPP personnel allowed deviations from the execution of the program itself, thereby creating additional conditions for the occurrence of an emergency.
The operators also did not fully realize that the RBMK reactor possesses a series of positive reactivity effects, which in some cases are triggered simultaneously, leading to the so-called "positive shutdown", that is, to an explosion. This instantaneous power effect played its fatal role …
But back to the test program itself. Let's try to understand why it turned out to be inconsistent with the higher organizations, which, like the management of the nuclear power plant, are responsible for the nuclear safety of not only the nuclear power plant itself, but also the state.
Immediately, one can afford far-reaching conclusions: irresponsibility, negligence in these state institutions has reached such a degree that they all considered it possible to remain silent without applying any sanctions, although both the General Designer and the General Customer (VPO Soyuzatomenergo) and Gosatomenergonadzor are endowed with such rights. Moreover, it is their direct responsibility. But these organizations have specific responsible people. Who are they? Are they consistent with the responsibilities assigned to them?
Let's look at it in order.
In Gidroproekt, the general designer of the Chernobyl nuclear power plant, V. S. Konviz was responsible for the safety of nuclear power plants. What kind of person is this? Experienced designer of hydroelectric power plants, candidate of technical sciences in hydraulic engineering. For many years (from 1972 to 1982) he was the head of the NPP design sector, since 1983 he was responsible for NPP safety. Having taken up the design of nuclear power plants in the seventies, Konviz hardly had any idea of what a nuclear reactor was, he studied nuclear physics from a high school textbook and attracted hydraulic engineers to work on nuclear design.
Here, perhaps, everything is clear. Such a person could not foresee the possibility of a catastrophe inherent in the program, and even in the reactor itself.
- But why did he take up not his own business? - the bewildered reader will exclaim.
- Because it is prestigious, monetary, convenient, - I will answer. - And why did Mayorets, Shcherbina undertake this business? This question and the list of names can be continued …
In the VPO Soyuzatomenergo-Association of the USSR Ministry of Energy and Electrification, which operates the NPP and is actually responsible for all actions of the operating personnel, the head was G. A. Veretennikov, a person who had never worked in the operation of nuclear power plants. From 1970 to 1982, he worked in the USSR State Planning Committee, first as a chief specialist, and then as a head of a subsection in the Energy and Electrification Department. He was involved in planning the supply of equipment for nuclear power plants. The supply business went badly for various reasons. From year to year, up to 50 percent of the planned equipment was not delivered.
Veretennikov was often ill, he had, as they said, a weak head, spasmodic vessels of the brain. But the internal attitude to occupy a high position was apparently strongly developed in him. In 1982, having included all his connections, he took up the vacant combined position of Deputy Minister - Head of the Soyuzatomenergo Association. She turned out to be beyond his powers, even purely physically. Spasms of the cerebral vessels, fainting, and prolonged lying in the Kremlin hospital began again.
One of the old employees of Glavatomenergo Yu. A. Izmailov joked about this:
- With us, under Veretennikov, it is almost impossible to find an atomic engineer in the head office who understands a lot about reactors and nuclear physics. But the accounting department, the procurement department and the planning department were incredibly bloated …
In 1984, the post-prefix "deputy minister" was reduced, and Veretennikov became simply the head of the Soyuzatomenergo association. This blow was worse for him than the Chernobyl explosion. His fainting became more frequent, and he went to the hospital again.
The head of the production department of Soyuzatomenergo E. S. Ivanov justified shortly before Chernobyl the frequent emergencies at nuclear power plants:
- None of the NPPs fully comply with the technological regulations. And it’s impossible. The practice of operation is constantly making its own adjustments …
Only the nuclear disaster at Chernobyl decided Veretennikov's fate. He was expelled from the party and dismissed from the post of the head of Soyuzatomenergo. We have to regret that our bureaucrats can be removed from the soft executive chairs only with the help of explosions …
In Gosatomenergonadzor, a fairly literate and experienced people gathered, headed by the chairman of the Committee, E. V. Kulov, an experienced nuclear physicist who had worked for a long time at the nuclear reactors of the Ministry of Medium Machine Building. But oddly enough, Kulov also ignored the crude test program from Chernobyl. Why, one wonders? Indeed, the Regulation on Gosatomenergonadzor, approved by the Resolution of the Council of Ministers of the USSR dated May 4, 1984, No. 409, provided that the main tasks of the Committee are:
State supervision over the observance by all ministries, departments, enterprises, organizations, institutions and officials of the established rules, norms and instructions on nuclear and technical safety in the design, construction and operation of nuclear power facilities.
The Committee is also given the right, in particular, in paragraph "g": to take responsible measures, up to the suspension of the operation of nuclear power facilities, in case of non-observance of safety rules and standards, detection of equipment defects, insufficient personnel competence, as well as in other cases when a threat is created operation of these facilities …
I remember that at one of the meetings in 1984, E. V. Kulov, who was only then appointed chairman of Gosatomenergonadzor, explained his functions to the assembled nuclear power engineers:
- Do not think that I will work for you. Figuratively speaking, I am a policeman. My job is to prohibit, cancel your wrong actions …
Unfortunately, as a "policeman" E. V. Kulov did not work in the case of Chernobyl …
What prevented him from suspending work at the fourth power unit of the Chernobyl nuclear power plant? After all, the test program did not stand up to criticism …
And what prevented Gidroproekt and Soyuzatomenergo?
Nobody intervened, as if they had conspired. What is the matter here? And the point here is a conspiracy of silence. In the absence of publicity of negative experience. No publicity - no lessons. After all, no one has notified each other about accidents at nuclear power plants for the last 35 years, no one demanded that the experience of these accidents be taken into account in their work. Therefore, there were no accidents. Everything is safe, everything is reliable … But it was not in vain that Abutalib said: "Whoever shoots at the Past from a pistol, therefore, the Future will shoot from a cannon." I would paraphrase specifically for nuclear power engineers: "therefore, the Future will hit with an explosion of a nuclear reactor … a nuclear catastrophe …"
Here it is necessary to add one more detail, which was not reflected in any of the technical reports on the incident. Here is this detail: the mode with the generator rotor run-out, used in one of the subsystems of the high-speed emergency reactor cooling system (ECCS), was planned in advance and was not only reflected in the test program, but was also prepared technically. Two weeks before the experiment, the MPA (maximum design basis accident) button was embedded on the control panel panel of the fourth power unit, the signal from which was pressed only in the high-gorilla electric circuits, but without instrumentation and the pumping part. That is, the signal from this button was purely imitation and passed "by" all the main settings and interlocks of the nuclear reactor. This was a serious mistake.
Since the beginning of the maximum design basis accident is considered to be a rupture of a suction or discharge manifold with a diameter of 800 millimeters in a solid-tight box, the settings for the operation of the emergency protection (EP) and the ECCS system were:
- pressure reduction on the suction line of the main circulation pumps, - reduction of the drop "lower water communications - drums-separators", - pressure increase in a solid-tight box.
When these settings are reached, in the normal case, emergency protection (EP) is triggered. All 211 pieces of absorbing rods fall down, cooling water from the ECCS tanks is cut in, emergency service pumps are turned on and diesel generators of reliable power supply are deployed. Emergency pumps for water supply from the bubbler pool to the reactor are also turned on. That is, there is more than enough protection if they are involved and will work at the right time …
So - all these protections and had to be brought to the "MPA" button. But, unfortunately, they were taken out of operation for fear of a thermal shock to the reactor, that is, the flow of cold water into the hot reactor. This frail thought, apparently, hypnotized both the management of the nuclear power plant (Bryukhanov, Fomin, Dyatlov) and the higher organizations in Moscow. Thus, the holy of holies of nuclear technology was violated. After all, if the maximum design basis accident was foreseen by the project, then it could have occurred at any time. And who, in this case, gave the right to deprive the reactor of all the protections provided for by the project and the rules of nuclear safety? Nobody gave it. They allowed themselves …
But the question is why the irresponsibility of Gosatomenergonadzor, Hydroproject and Soyuzatomenergo did not alert the director of the Chernobyl NPP, Bryukhanov, and the chief engineer Fomin? After all, it is impossible to work according to an uncoordinated program. Who are Bryukhanov and Fomin? What kind of people are these, what kind of specialists?
I met with Viktor Petrovich Bryukhanov in the winter of 1971, having arrived at the construction site of a nuclear power plant, in the village of Pripyat, directly from a Moscow clinic, where he was treated for radiation sickness. I still felt bad, but I could walk and decided that, working, I would get back to normal faster.
Having signed up that I was leaving the clinic of my own free will, I got on the train and in the morning I was already in Kiev. From there I took a taxi to Pripyat in two hours. On the road several times the consciousness, nausea, dizziness became turbulent. But he was drawn to work, the appointment to which he received shortly before his illness.
I was treated in the same sixth clinic in Moscow, where in fifteen years deadly irradiated firefighters and people of operating personnel who were injured in the nuclear disaster of the fourth power unit will be brought …
And then, in the early seventies, there was still nothing on the site of the future nuclear power plant. They dug a pit for the main building. Around - a rare young pine forest, like nowhere else, heady air. Eh, you should know in advance where you shouldn't start digging pits!
Even when approaching Pripyat, I noticed a sandy hilly area overgrown with a low-growing forest, frequent bald patches of clean yellow sand against a background of dark green moss. No snow. In other places, warmed by the sun, the grass turned green. Silence and primordiality.
- Waste lands, - said the taxi driver, - but ancient. Here, in Chernobyl, Prince Svyatoslav chose his bride. They say that she was a restive bride … More than a thousand years of this small town. But he survived, did not die …
The winter day in the village of Pripyat was sunny and warm. This often happened here and then. It looks like winter, but it smells like spring all the time. The taxi driver stopped near a long wooden barrack, which temporarily housed the management of the nuclear power plant under construction and the construction management.
I entered the barrack. The floor sagged and creaked underfoot. Here is the director's office - a small room with an area of about six square meters. The same office belongs to the chief engineer M. P. Alekseev, the future deputy chairman of Gosatomenergonadzor. Following the results of the Chernobyl disaster, he will be given a severe reprimand and entered into the registration card. Until then …
When I entered, Bryukhanov got up, short, very curly, dark-haired, with a wrinkled tanned face. Smiling embarrassedly, he shook my hand. In all his appearance, one could feel that he was a gentle, flexible man.
Later, this first impression was confirmed, but some other aspects were revealed in him, in particular, internal stubbornness with a lack of knowledge of people, which forced him to reach out to experienced in the everyday sense, but sometimes not always clean workers. After all, then Bryukhanov was very young - thirty-six years old. He is a turbine operator by profession and work experience. Graduated with honors from the Power Engineering Institute. He advanced at the Slavyanskaya GRES (coal-fired station), where he showed himself well at the start-up of the unit. He did not go home for days, he quickly and competently resolved issues. And in general, I later learned, working side by side with him for several years, that he is a good engineer, sharp-witted, efficient, but the problem is that he is not an atomic engineer. And this, it turns out, ultimately, as shown by Chernobyl, is the most important thing. At a nuclear power plant, you must first of all be a professional atomic engineer …
The Deputy Minister of the Ministry of Energy of Ukraine, who supervises the Slavyanskaya GRES, noticed Bryukhanov and nominated him as a candidate for Chernobyl …
With general education, I mean the breadth of horizons, erudition, humanitarian culture, Bryukhanov was rather weak. By this, to some extent, I explained later his desire to surround himself with dubious connoisseurs of life …
And then, in 1971, I introduced myself, and he happily said:
- Ah, Medvedev! We are waiting for you. Get to work soon.
Bryukhanov left the office and called the chief engineer.
Mikhail Petrovich Alekseev entered, who had already worked here for several months. He came to Pripyat from the Beloyarsk NPP, where he worked as deputy chief engineer for the third unit under construction, which was listed so far only on paper. Alekseev had no experience of atomic operation and until Beloyarka worked for 20 years at thermal power plants. And as it soon became clear, he was eager to go to Moscow, where three months after the start of my work at the Chernobyl nuclear power plant and left. I have already told about the punishment suffered by him as a result of Chernobyl. His chief for Moscow work, chairman of Gosatomenergonadzor, E. V. Kulov, was punished more severely. He was fired from his job and expelled from the party. Bryukhanov suffered the same punishment before the trial …
But this happened fifteen years later. And during these fifteen years, important events have taken place, mainly in the personnel policy at the nuclear power plant. Bryukhanov also pursued this policy. It was she who led, in my opinion, to April 26, 1986 …
From the very first months of my work at the Chernobyl nuclear power plant (before that I worked for many years as a shift supervisor at another plant), I started training the personnel of workshops and services. He proposed to Bryukhanov candidates with many years of experience at nuclear power plants. As a rule, Bryukhanov did not directly refuse, but did not hire him either, gradually offering or even sending workers of thermal stations to these positions. At the same time, he said that, in his opinion, at the NPP, experienced station workers should work, who are well aware of powerful turbine systems, switchgear and power distribution lines.
With great difficulty, over Bryukhanov's head, with the support of Glavatomenergo, I managed to equip the reactor and special chemical departments with the necessary specialists. Bryukhanov staffed turbine operators and electricians. Around the end of 1972, they came to work at the Chernobyl nuclear power plant N. M. Fomin and T. G. Plokhiy … Bryukhanov offered the first to the position of head of the electrical shop, the second - to the position of deputy head of the turbine shop. Both of these people are direct candidates for Bryukhanov, and Fomin, an electrician by work experience and education, was nominated for the Chernobyl nuclear power plant from the Zaporozhye state district power station (thermal station), before which he worked in the Poltava power grids. I am calling these two names, because in fifteen years they will be associated with two major accidents in Balakovo and Chernobyl …
As Deputy Chief Engineer for Operations, I talked with Fomin and warned him that the nuclear power plant was a radioactive and extremely complex enterprise. Did he think hard, leaving the electrical department of the Zaporozhye state district power station?
Fomin has a beautiful white-toothed smile. It seems that he knows this and smiles almost continuously out of place and out of place. Smiling slyly, he replied that the NPP is a prestigious, ultra-modern enterprise and that it is not the gods who burn the pots …
He had a rather pleasant energetic baritone, interspersed with alto notes in moments of excitement. A square, angular figure, a narcotic gleam of dark eyes. In his work, he is clear-cut, executive, demanding, impulsive, ambitious, vindictive. The gait and movement are sharp. It was felt that internally he was always compressed like a spring and ready for a jump … I dwell on him in such detail because he was to become a kind of atomic Herostratus, a somewhat historical personality, with whose name, starting from April 26, 1986, one of the most terrible nuclear disasters at nuclear power plants …
Taras Grigorievich Plokhiy, on the contrary, is lethargic, circumstantial, a typical phlegmatic, his manner of speech is stretched, tedious, but meticulous, stubborn, hard-working. At first glance, one could say about him: tyukha, slob, if not for his methodicalness and perseverance in work. In addition, much was concealed by his proximity to Bryukhanov (they worked together at the Slavyanskaya TPP). In the light of this friendship, he seemed to many more significant and energetic …
After my departure from Pripyat to work in Moscow, Bryukhanov began to actively promote Plokhiy and Fomin to the leading echelon of the Chernobyl nuclear power plant. Bad was walking ahead. He eventually became Deputy Chief Engineer for Operations, then Chief Engineer. In this position, he did not stay long and, at the suggestion of Bryukhanov, was nominated as a chief engineer for the Balakovo nuclear power plant under construction, a station with a pressurized water reactor, the design of which he did not know, and as a result, in June 1985, during commissioning, due to negligence and sloppiness committed by the operating personnel under his leadership, and gross violation of technological regulations, an accident occurred, in which fourteen people were boiled alive. Corpses from the ring-shaped rooms around the reactor shaft were dragged out to the emergency airlock and piled at the feet of an incompetent chief engineer, pale as death …
Meanwhile, at the Chernobyl nuclear power plant, Bryukhanov continued to promote Fomin in his service. He went by leaps and bounds to the position of deputy chief engineer for installation and operation and soon replaced Plokhiy as chief engineer. It should be noted here that the USSR Ministry of Energy did not support Fomin's candidacy. VK Bronnikov, an experienced reactor engineer, was offered for this position. But Bronnikov was not approved in Kiev, calling him an ordinary technician. Like de, Fomin is a tough, demanding leader. We want him. And Moscow conceded. Fomin's candidacy was agreed with the department of the Central Committee of the CPSU, and the matter was decided. The price of this concession is known …
Here it would be necessary to stop, look around, reflect on the Balakovo experience, increase vigilance and caution, but …
At the end of 1985, Fomin gets into a car accident and breaks his spine. Prolonged paralysis, frustration. But the powerful organism coped with the illness, Fomin recovered and went to work on March 25, 1986, a month before the Chernobyl explosion. I was in Pripyat just at that time with an inspection of the 5th power unit under construction, where things were not going well, the progress of work was restrained by the lack of design documentation and technological equipment. I saw Fomin at a meeting that we gathered specially for the 5th power unit. He passed great. In all his appearance there was some kind of lethargy and the stamp of the suffering he had endured. The car accident did not go unnoticed.
- Maybe you'd better rest for a couple of months more, get medical treatment? I asked him. - The injury is serious.
“No… It's okay,” he laughed abruptly and somehow, it seemed to me, with a deliberate laugh, while his eyes, like fifteen years ago, had a feverish, angry, tense expression.
And yet, I believed that Fomin was not well, that it was dangerous not only for him personally, but also for the nuclear power plant, for the four nuclear power units, the operational management of which he exercised. Concerned, I decided to share my concerns with Bryukhanov, but he also began to reassure me: “I think it's okay. He recovered. In work, it will soon come to normal …"
Such confidence embarrassed me, but I did not insist. After all, is it my business? The person may really feel good. In addition, now I was engaged in the construction of a nuclear power plant. Operational matters in my current position did not concern me, and therefore I could not decide on the removal or temporary replacement of Fomin. After all, doctors, experienced specialists, were discharged to work for him, they knew what they were doing … And yet, there was doubt in my soul, and I could not once again draw Bryukhanov's attention to, as it seemed to me, the fact of Fomin's ill health. Then we got to talking. Bryukhanov complained that there are many leaks at the Chernobyl nuclear power plant, that fittings are not holding, drainages and air vents are leaking. The total flow rate of leaks is almost always 50 cubic meters of radioactive water per hour. They barely manage to process it in evaporation plants. A lot of radioactive dirt. He said that he was already feeling very tired and would like to go somewhere else for another job …
He recently returned from Moscow, from the 27th Congress of the CPSU, at which he was a delegate.
But what happened at the fourth power unit of the Chernobyl nuclear power plant on April 25, while I was still at the Crimean station, and then flew to the Il-86 to Moscow?
At 1:00 am on April 25, 1986, the operating personnel began to reduce the power of the reactor No. 4, which was operating at nominal parameters, that is, by 3000 MW thermal.
The reduction in capacity was carried out by order of the deputy chief engineer for the operation of the second stage of the nuclear power plant, A. S. Dyatlov, who was preparing the fourth unit for the implementation of the program approved by Fomin.
At 13:05 the same day, the turbine generator No. 7 was disconnected from the network with the thermal power of the reactor 1600 MW thermal. The power supply for the unit's own needs (four main circulation pumps, two electric feed pumps, etc.) was transferred to the tires of the turbine generator No. 8, which remained in operation, with which the tests planned by Fomin were to be carried out.
At 14:00, in accordance with the experiment program, the emergency reactor cooling system (ECCS) was disconnected from the multiple forced circulation circuit cooling the core. This was one of Fomin's gross and fatal mistakes. At the same time, it should be emphasized that this was done deliberately in order to exclude possible thermal shock when cold water flows from the ECCS tanks into the hot reactor.
After all, when the acceleration on prompt neutrons begins, the water supply to the main circulation pumps will be disrupted, and the reactor will be left without cooling water, 350 cubic meters of emergency water from the ECCS tanks, perhaps, would have saved the situation by extinguishing the steam effect of reactivity, the most significant of all. Who knows what the outcome would be. But … What a person incompetent in nuclear matters with a keen internal attitude towards leadership, with a desire to stand out in a prestigious business and to prove that a nuclear reactor is not a transformer and can work without cooling, will not do …
It is difficult now to imagine what secret plans illuminated Fomin's consciousness in those fateful hours, but only a person who did not understand neutron at all could have turned off the emergency cooling system of the reactor, which in critical seconds could have saved from an explosion by drastically reducing the vapor content in the core. -physical processes in a nuclear reactor, or at least extremely arrogant.
But nevertheless, it was done, and it was done, as we already know, deliberately. Apparently, the deputy chief engineer for operations A. S. Dyatlov, and all personnel of the control service of the fourth power unit. Otherwise, at least one of them should have come to his senses at the moment the ECCS was turned off and shouted:
- Set aside! What are you doing, brothers! Take a look around. Nearby, close by, are the ancient cities: Chernobyl, Kiev, Chernigov, the most fertile lands of our country, the blossoming gardens of Ukraine and Belarus … New lives are being registered in the Pripyat maternity hospital! They must come to a clean world, to a clean one! Come to your senses!
But no one came to his senses, no one shouted. The ECCS was quietly turned off, the valves on the water supply line to the reactor were de-energized in advance and locked so that, if necessary, they would not even be opened manually. Otherwise, they can foolishly open up, and 350 cubic meters of cold water will hit the hot reactor … But in the event of a maximum design-basis accident, cold water will still go into the core. Here, of two evils, you need to choose the lesser. It is better to supply cold water to a hot reactor than to leave the hot core without water. After taking off their head, they don't cry for their hair. ECCS water comes in just then. when she needs to do, and heatstroke here is incommensurate with an explosion …
Psychologically, the question is very difficult. Well, of course, the conformism of operators who have lost the habit of thinking independently, the negligence and slovenliness that penetrated, established themselves in the management service of the nuclear power plant and became the norm. Also - disrespect for the nuclear reactor, which was perceived by the operators almost like a Tula samovar, maybe a little more complicated. Forgetting the golden rule of workers in explosive industries: “Remember! Incorrect actions - explosion! There was also an electrotechnical tilt in thinking, because the chief engineer is an electrician, moreover, after a severe spinal cord injury, the consequences of which for the psyche did not go unnoticed. The oversight of the psychiatric service of the medical unit of the Chernobyl nuclear power plant, which must vigilantly monitor the mental state of nuclear operators, as well as the management of the nuclear power plant, and remove them from work in time if necessary, is also indisputable …
And here again it should be recalled that the emergency reactor cooling system (ECCS) was deliberately put out of operation in order to avoid thermal shock to the reactor when the "MPA" button was pressed. Therefore, Dyatlov and the operators were sure that the reactor would not fail. Overconfidence? Yes. It is here that you begin to think that the operators did not fully understand the physics of the reactor, did not foresee the extreme development of the situation. I think that the relatively successful operation of the Chernobyl nuclear power plant for ten years also contributed to the demagnetization of people. And even the alarm signal - the partial melting of the core at the first power unit of this station in September 1982 - did not serve as a proper lesson. And he could not serve. After all, for many years accidents at nuclear power plants were hidden, although the operators of different nuclear power plants partly learned about them from each other. But they did not attach due importance, "Since the authorities are keeping quiet, God himself ordered us." Moreover, accidents were already perceived as inevitable, albeit unpleasant satellites of nuclear technology.
For decades, the confidence of atomic operators has been forged, which over time has turned into arrogance and the possibility of completely violating the laws of nuclear physics and the requirements of technological regulations, otherwise …
However, the beginning of the experiment was postponed. At the request of the dispatcher Kyivenergo at 14:00 on April 25, 1986, the unit's decommissioning was delayed.
In violation of the technological regulations, the operation of the fourth power unit at this time continued with the emergency reactor cooling system (ECCS) turned off, although formally the reason for such work was the presence of the "MPA" button and the criminal blocking of protections due to fear of throwing cold water when pressed into a hot reactor …
At 11.10 p.m. (Yuri Tregub was the shift supervisor of the fourth power unit at that time), the power reduction was continued.
At 24 hours 00 minutes Yuri Tregub passed the shift Alexander Akimov, and his senior reactor control engineer (abbreviated as SIUR) handed over the shift to the senior reactor control engineer Leonid Toptunov …
Here the question arises: what if the experiment were carried out on Tregub's shift, would the reactor explode? I think no. The reactor was in a stable, controllable state, the operational reactivity margin was more than 28 absorbing rods, the power level was 1700 MW thermal. But the end of the experiment with an explosion could have occurred in this watch, if, when the local automatic control system (abbreviated LAR) was turned off, the senior reactor control engineer (SRIU) of the Tregub shift would make the same mistake as Toptunov, and having made it, he would rise from "Iodine pit" …
It is difficult to say what would have happened, but I would like to hope that the SIUR of the change of Yuri Tregub would have worked more professionally than Leonid Toptunov and would have shown more persistence in defending his innocence. So the human factor is obvious …
But events developed the way they were programmed by Fate. And the seeming delay given to us by the dispatcher Kyivenergo, having shifted the tests from 14:00 on April 25 to 1 hour 23 minutes on April 26, turned out to be in fact only a direct path to an explosion …
In accordance with the test program, the generator rotor run-out with a load of auxiliary needs was supposed to be carried out at a power of 700-1000 MW of thermal power. It should be emphasized here that such a run-out should have been carried out at the time of shutdown of the reactor, because in the case of a maximum design basis accident, the emergency protection of the reactor (EP) according to five emergency settings falls down and muffles the apparatus. But another, catastrophically dangerous path was chosen - to make the generator rotor run out while the reactor was running. Why such a dangerous regime was chosen remains a mystery. One can only assume that Fomin wanted pure experience …
What happened next is what happened. It should be clarified that the absorbing rods can be controlled all at once or in parts, in groups. When one of these local systems was turned off, which is stipulated by the regulations for operating a nuclear reactor at low power, Leonid Toptunov SIUR could not quickly eliminate the imbalance that appeared in the control system (in its measuring part). As a result, the reactor power dropped to below 30 MW thermal. The poisoning of the reactor with decay products began. It was the beginning of the end …
Here it is necessary to briefly describe the Deputy Chief Engineer for the operation of the second stage of the Chernobyl NPP Anatoly Stepanovich Dyatlov … Tall, thin, with a small angular face, with a smoothly combed back gray from gray hair and evasive, deeply sunken dull eyes, A. S. Dyatlov appeared at the nuclear power plant somewhere in the middle of 1973. His questionnaire was given to me by Bryukhanov for study ahead of time. From Bryukhanov, Dyatlov came to me for an interview some time later.
The questionnaire indicated that he worked as the head of a physical laboratory at one of the enterprises of the Far East, where, as far as could be judged from the questionnaire, he was engaged in small ship nuclear installations. This was confirmed in a conversation with him.
“I investigated the physical characteristics of the cores of small reactors,” he said then.
He never worked at a nuclear power plant. He does not know the thermal schemes of the station and uranium-graphite reactors.
- How will you work? - I asked him. - The object is new for you.
- Let's learn, - he said somehow strainedly, - there valves, pipelines … It's easier than the physics of a reactor …
Strange demeanor: head bent forward, escaping gaze of gloomy gray eyes, strained intermittent speech. He seemed to be squeezing words out of himself with great difficulty, separating them with significant pauses. Listening to him was not easy, the character in him felt heavy.
I reported to Bryukhanov that it was impossible to accept Dyatlov as head of the reactor department. It will be difficult for him to manage operators not only because of his character traits (he clearly did not know the art of communication), but also from the experience of previous work: a pure physicist, he does not know atomic technology.
Bryukhanov listened to me in silence. He said he would think about it. A day later, an order was issued to appoint Dyatlov as deputy head of the reactor department. Somewhere Bryukhanov listened to my opinion, appointing Dyatlov to a lower position. However, the direction of the "reactor shop" remained. Here, I think, Bryukhanov made a mistake, and as life has shown - fatal …
The forecast regarding Dyatlov was confirmed: he is clumsy, slow-witted, difficult and conflicted with people …
While I was working at the Chernobyl nuclear power plant, Dyatlov did not advance in the service. Moreover, later I planned to transfer him to a physical laboratory, where he would be in place.
After my departure, Bryukhanov began to move Dyatlov, he became the head of the reactor department, and then the deputy chief engineer for the operation of the second stage of the nuclear power plant.
I will give the characteristics given to Dyatlov by his subordinates, who have worked with him side by side for many years.
Davletbaev Razim Ilgamovich - deputy head of the turbine shop of the fourth unit:
Smagin Viktor Grigorievich - shift supervisor of the fourth unit:
V. G. Smagin about N. M. Fomin:
So - was Dyatlov capable of instantaneous, the only correct assessment of the situation at the moment of its transition to an accident? I don't think I can. Moreover, in him, apparently, the necessary reserve of caution and a sense of danger, so necessary for the head of atomic operators, was not sufficiently developed. But there is more than enough arrogance, disrespect for operators and technological regulations …
It was these qualities that unfolded in Dyatlov in full force, when, when the local automatic control system (LAR) was turned off, the senior reactor control engineer (SIUR) Leonid Toptunov was unable to keep the reactor at a power of 1500 MW and "dropped" to 30 MW thermal.
Toptunov made a gross mistake. With such a low power, intense poisoning of the reactor with decay products (xenon, iodine) begins. Restoring the parameters becomes difficult or even impossible. All this meant: the experiment with the rotor run-out fails, which was immediately understood by all atomic operators, including SIUR Leonid Toptunov, unit shift supervisor Alexander Akimov. Anatoly Dyatlov, Deputy Chief Engineer for Operations, also understood this.
A rather dramatic situation arose in the control room of the fourth power unit. Usually slowed down Dyatlov, with uncharacteristic agility, ran around the panels of the operator's console, belching foul language and curses. His hoarse, quiet voice now took on an angry metallic sound.
- Japanese carp! You don't know how! Failed mediocre! Disrupt the experiment! Fuck your mother!
His anger was understandable. The reactor is poisoned by decay products. It is necessary either to immediately raise the power, or to wait a day until it is poisoned. And we had to wait … Ah, Dyatlov, Dyatlov! You did not take into account that the poisoning of the core is proceeding faster than you expected. Stop! Maybe humanity will blow the Chernobyl disaster …
But he didn't want to stop. Throwing thunder and lightning, he rushed around the block control room and wasted precious minutes. We must immediately raise the power!
But Dyatlov continued to discharge his battery.
SIUR Leonid Toptunov and the head of the block shift Akimov thought about it, and there was something. The fact is that the drop in power to such low values occurred from the level of 1500 MW, that is, from a 50 percent value. The operational reactivity margin was 28 rods (that is, 28 rods were immersed in the core). Restoration of the parameters was still possible … The technological regulations forbade the increase in power if the drop occurred from 80% with the same reactivity margin, because in this case the poisoning is more intense. But the values of 80 and 50 percent were too close. As time went on, the reactor was poisoned. Dyatlov continued to scold. Toptunov was inactive. It was clear to him that he would hardly be able to rise to the previous power level, that is, up to 50 percent, and if he did, then with a sharp decrease in the number of rods immersed in the zone, which required an immediate shutdown of the reactor. So … Toptunov made the only correct decision.
- I will not go up! - Toptunov said firmly. Akimov supported him. Both expressed their concerns to Dyatlov.
- What are you gaping, Japanese crucian carp! - Dyatlov pounced on Toptunov, - After falling from 80 percent, according to the regulations, it is allowed to rise in a day, and you fell from 50 percent! The regulations do not prohibit. But you will not rise, Tregub will rise … - It was already a psychic attack (Yuri Tregub, the head of the unit shift, who passed the shift to Akimov and stayed to see how the tests were going, was there). It is not known, however, whether he would agree to raise the power. But Dyatlov calculated correctly, Leonid Toptunov was frightened by the shout of his superiors, betrayed his professional instinct. Young, of course, only 26 years old, inexperienced. Eh, Toptunov, Toptunov … But he was already thinking:
"The operational reactivity margin of 28 rods … To compensate for the poisoning, it will be necessary to pull out five or seven more rods from the reserve group … Maybe I will slip through … I will disobey, they will be fired …" (Toptunov told about this in the Pripyat medical unit shortly before being sent to Moscow.)
Leonid Toptunov began to increase power, thereby signing a death warrant for himself and many of his comrades. Under this symbolic verdict, the signatures of Dyatlov and Fomin are also clearly visible. The signature of Bryukhanov and many other, higher-ranking comrades is legible …
And yet, in fairness, I must say that the death sentence was predetermined to some extent by the very design of the RBMK-type reactor. It was only necessary to ensure the coincidence of circumstances under which an explosion is possible. And it was done …
But we are getting ahead of ourselves. There was, there was still time to change my mind. But Toptunov continued to increase the reactor power. Only by 1:00 a.m. on April 26, 1986 it was possible to stabilize it at the level of 200 MW thermal. During this period, the poisoning of the reactor with decay products continued, a further increase in power was difficult due to the small operational reactivity margin, which by that time was much lower than the scheduled one. (According to the USSR's report to the IAEA, it was 6-8 rods, according to the statement of the dying Toptunov, who looked at the printout of the Skala machine seven minutes before the explosion, - 18 rods.)
To make it clear to the reader, let me remind you that the operational reactivity margin is understood as a certain number of absorbing rods immersed in the core and located in the region of high differential efficiency. (It is determined by conversion to fully submerged rods.) For a RBMK-type reactor, the operational reactivity margin is assumed to be 30 rods. In this case, the rate of injection of negative reactivity when the emergency protection of the reactor (EP) is triggered is 1V (one beta) per second, which is sufficient to compensate for the positive effects of reactivity during normal operation of the reactor.
I must say that, answering my questions, VG Smagin, the shift supervisor of the ChNPP unit 4, said that the minimum permissible regulatory value of the operational reactivity margin of the reactor of the 4th unit was 16 rods. In reality, as A. Dyatlov said in his letter already from places of detention, at the time of pressing the "AZ" button, there were 12 rods.
This information does not change the qualitative picture: the real operational reactivity margin was below the scheduled one. The very same technological regulations, stained with radioactivity, were delivered to Moscow, to the commission for the investigation of the accident, and 16 rods in the regulations turned into thirty rods in the USSR's report to the IAEA. It is also possible that in the regulations the number of rods of the operational reactivity margin, contrary to the recommendation of the Kurchatov Institute of Atomic Energy, was underestimated from 30 to 16 rods at the power plant itself, which allowed operators to manipulate a large number of control rods. The possibilities for control in this case seem to expand, but the probability of the transition of the reactor to an unstable state increases sharply …
But back to our analysis.
In fact, the operational reactivity margin was 6-8 rods according to the report to the IAEA and 18 rods according to Toptunov's testimony, which significantly reduced the effectiveness of the emergency protection of the reactor, which became therefore uncontrollable.
This is explained by the fact that Toptunov, leaving the "iodine pit", removed several rods from the group of the emergency supply …
Nevertheless, it was decided to continue the tests, although the reactor was already virtually uncontrollable. Apparently, the confidence of the senior reactor control engineer Toptunov and the shift supervisor of the Akimov unit - the main responsible for the nuclear safety of the reactor and the nuclear power plant as a whole - was great. True, they had doubts, there were attempts to disobey Dyatlov at the fateful moment of making a decision, but still the main thing against the background of all this was a strong inner confidence in success. The hope that it will not fail and this time will help out the reactor. There was, as I have already said, the inertia of the usual conformist thinking. Indeed, over the past 35 years, there have been no accidents at nuclear power plants of a global nature. And about those that were, no one even heard of. Everything was carefully hidden. The guys had no negative experience of the past. And the operators themselves were young and not vigilant enough. But not only Toptunov and Akimov (they stepped into the night), but also the operators of all previous shifts on April 25, 1986, did not show due responsibility and, with a light heart, went for a gross violation of technological regulations and nuclear safety rules.
Indeed, it was necessary to completely lose the sense of danger, to forget that the main thing at a nuclear power plant is the nuclear reactor, its core. The main motive in the behavior of the staff was the desire to finish the tests faster. I would say that there was no proper love for their work here, because such necessarily presupposes deep thoughtfulness, genuine professionalism and vigilance. Without this, it is better not to take control of such a dangerous device as an atomic reactor.
Violations of the established procedure during the preparation and conduct of tests, negligence in the management of the reactor plant - all this suggests that the operators did not deeply understand the peculiarity of the technological processes taking place in a nuclear reactor. Not everyone, apparently, was aware of the specifics of the design of absorbing rods …
There were twenty-four minutes fifty-eight seconds left before the explosion …
Let's summarize the gross violations, both included in the program and committed in the process of preparing and conducting tests:
- striving to get out of the "iodine pit", they reduced the operational reactivity margin below the permissible value, thereby making the emergency protection of the reactor ineffective;
- the LAR system was mistakenly turned off, which led to a failure of the reactor power below that provided for by the program; the reactor was in a difficult to control state;
- all eight main circulating pumps (MCPs) were connected to the reactor with an emergency excess of flow rates for individual MCPs, which made the coolant temperature close to the saturation temperature (meeting the program requirements);
- intending, if necessary, to repeat the experiment with de-energizing, blocked the protection of the reactor on the signal to stop the apparatus when two turbines were turned off;
- blocked the water level and steam pressure protections in the separator drums, trying to carry out tests, despite the unstable operation of the reactor. Thermal protection has been disabled;
- they turned off the protection systems against the maximum design basis accident, trying to avoid false operation of the ECCS during the tests, thereby losing the opportunity to reduce the scale of the probable accident;
- blocked both emergency diesel generators as well as the working and starting-standby transformers, disconnecting the unit from the emergency power supplies and from the power system, trying to conduct a "clean experiment", and in fact completing the chain of prerequisites for an ultimate nuclear catastrophe …
All of the above took on an even more ominous coloration against the background of a number of unfavorable neutron-physical parameters of the RBMK reactor, which has a positive vapor effect of reactivity 2v (two beta), a positive temperature effect of reactivity, as well as a faulty design of absorbing rods of the reactor protection control system (abbreviated as CPS).
The fact is that with a core height of seven meters, the absorbing part of the rod had a length of five meters, and below and above the absorbing part there were hollow sections of a meter. The lower end of the absorbing rod, which leaves at full immersion below the core, is filled with graphite. With this design, the control rods at the top, when they are introduced into the reactor, enter the core first with the lower graphite tip, then a hollow meter section enters the zone and only after that the absorbing part. In total, there are 211 absorber rods at the Chernobyl 4th power unit. According to the USSR report to the IAEA, 205 rods were in the extreme upper position, according to SIUR Toptunov, there were 193 rods at the top. The simultaneous introduction of such a number of rods into the core gives at the first moment a burst of positive reactivity due to dehydration of the CPS channels, since the zone first includes graphite limit switches (5 meters long) and hollow sections of a meter in length, displacing water. The reactivity surge reaches half beta and is not terrible with a stable, controlled reactor. However, if the unfavorable factors coincide, this additive may turn out to be fatal, because it will lead to uncontrollable acceleration.
The question arises: did the operators know about this or were they in the holy ignorance? I think they knew a little. In any case, they should have known. SIUR Leonid Toptunov in particular. But he is a young specialist, knowledge has not yet entered flesh and blood …
But the head of the unit shift, Alexander Akimov, I might not know, because I never worked as SIUR. But he studied the design of the reactor, passed exams for the workplace. However, this subtlety in the design of the absorbing rod could pass by the consciousness of all operators, because it was not directly associated with a danger to human life. But it was in the image of this structure that the death and horror of the Chernobyl nuclear disaster lurked until the time.
I also think that Bryukhanov, Fomin and Dyatlov presented a rough design of the rod, not to mention the designers and developers of the reactor, but they did not think that the future explosion was hidden in some end sections of the absorbing rods, which are the most important protection system for a nuclear reactor. What was supposed to protect killed, that's why they did not expect death from here …
But after all, reactors must be designed so that they self-extinguish during unforeseen accelerations. This rule is the holy of holies for the design of nuclear controlled devices. And I must say that the pressurized water reactor of the Novovoronezh type meets these requirements.
Yes, neither Bryukhanov, nor Fomin, nor Dyatlov brought to their consciousness the possibility of such a development of events. But in ten years of operating a nuclear power plant, you can graduate from the Physics and Technology Institute twice and master nuclear physics to the finest details. But this is if you really study and root for your cause, and not rest on your laurels …
Here the reader must briefly explain that an atomic reactor can be controlled only thanks to the fraction of delayed neutrons, which is denoted by the Greek letter b (beta). According to nuclear safety rules, the rate of increase in reactivity is safe at 0.0065 V, effective every 60 seconds. With an excess reactivity equal to 0.5 V, acceleration on prompt neutrons begins …
The same violations of the regulations and protection of the reactor by the operating personnel, which I spoke about above, threatened to release a reactivity equal to at least 5 V, which meant a fatal explosive acceleration.
Did Bryukhanov, Fomin, Dyatlov, Akimov, Toptunov represent this whole chain? The first two probably did not represent the whole chain. The last three - theoretically should have known, practically, I think not, which is confirmed by their irresponsible actions.
Akimov, right up to his death on May 11, 1986, repeated, while he could speak, one thought that tormented him:
- I did everything right. I don't understand why this happened.
All that also says that emergency training at nuclear power plants, theoretical and practical training of personnel was carried out very badly, and mainly within the framework of a primitive management algorithm that does not take into account deep processes in the core of a nuclear reactor at each given operational time interval.
The question arises - how did you come to such demagnetization, to such criminal negligence? Who and when put into the program of our destiny the possibility of a nuclear catastrophe in the Belarusian-Ukrainian Polesie? Why was the uranium-graphite reactor chosen for installation 130 kilometers from the capital of Ukraine, Kiev?
Let's go back fifteen years ago, in October 1972, when I worked as a deputy chief engineer at the Chernobyl nuclear power plant. Already at that time, many had similar questions.
One day in October 1972, Bryukhanov and I went to Kiev in a gas truck at the call of the then Minister of Energy of the Ukrainian SSR A. N. Makukhin, who nominated Bryukhanov to the post of director of the Chernobyl nuclear power plant. Makukhin himself is a heat power engineer by education and work experience.
On the way to Kiev, Bryukhanov told me:
- Do you mind if we carve out an hour or two, read the minister and his deputies a lecture on nuclear energy, on the design of a nuclear reactor? Try to be popular, otherwise they, like me, understand little at nuclear power plants …
“With pleasure,” I replied.
The Minister of Energy of the Ukrainian SSR, Aleksey Naumovich Makukhin, was very bossy. The stone expression on the rectangular face was intimidating. He spoke abruptly. A speech of a self-confident foreman.
I told the audience about the device of the Chernobyl reactor, about the layout of the nuclear power plant and about the features of this type of nuclear power plant.
I remember Makukhin asked:
- In your opinion, the reactor was chosen well or..? I mean, Kiev is still nearby …
- I think, - I replied, - for the Chernobyl nuclear power plant, not a uranium-graphite one, but a pressurized water reactor of the Novovoronezh type would be more suitable. The double-circuit station is cleaner, the length of pipelines is shorter, and the activity of emissions is less. In a word, it's safer …
- Are you familiar with the arguments of Academician Dollezhal? After all, he does not advise putting forward RBMK reactors in the European part of the country … But something is vaguely arguing this thesis. Have you read his conclusion?
- I read it … Well, what can I say … Dollezhal is right. Not worth pushing. These reactors have extensive Siberian operational experience. They have established themselves there, so to speak, from the "dirty side". This is a serious argument …
- Why didn't Dollezhal show persistence in defending his idea? Makukhin asked.
- I don’t know, Alexey Naumovich, - I spread my hands, - apparently, there were forces more powerful than Academician Dollezhal …
- And what are the design emissions of the Chernobyl reactor? - Makukhin asked more anxiously.
- Up to four thousand curies a day.
- And at Novovoronezhsky?
- Up to one hundred curies per day. The difference is significant.
- But academicians … The use of this reactor is approved by the Council of Ministers … Anatoly Petrovich Aleksandrov praises this reactor as the safest and most economical. You, comrade Medvedev, have exaggerated the colors. But nothing … We will master … It is not the gods who burn the pots … The operators will have to organize things so that our first Ukrainian reactor is cleaner and safer than Novovoronezh …
In 1982, A. N. Makukhin was transferred to the central office of the USSR Ministry of Energy as First Deputy Minister for the Operation of Power Plants and Networks.
On August 14, 1986, following the results of the Chernobyl disaster, by the decision of the Party Control Committee under the Central Committee of the CPSU for failure to take appropriate measures to improve the reliability of the operation of the Chernobyl nuclear power plant, A. N. Makukhin, First Deputy Minister of Energy and Electrification of the USSR, was given a strict party reprimand without being dismissed from his job.
But even then, in 1972, it was possible to change the type of the Chernobyl reactor to a water-moderated one and thereby dramatically reduce the possibility of what happened in April 1986. And the word of the Minister of Energy of the Ukrainian SSR would not be the last here.
One more characteristic episode should be mentioned. In December 1979, already working in Moscow, at the nuclear-building association Soyuzatomenergostroy, I went on an inspection trip to the Chernobyl nuclear power plant to control the construction of the 3rd power unit.
The then first secretary of the Kiev regional committee of the Communist Party of Ukraine Vladimir Mikhailovich Tsybulko took part in the meeting of nuclear engineers. He was silent for a long time, carefully listening to the speakers, then he made a speech. His burnt face with traces of keloid scars (during the war he was a tanker and burned in a tank) flushed deeply. He looked into the space in front of him, without stopping his gaze on someone, and spoke in the tone of a person not used to objections. But in his voice, there were also fatherly notes, notes of care and good wishes. I listened and involuntarily thought about how easily non-professionals in the nuclear power industry are ready to rant about the most complicated issues, the nature of which is not clear to them, ready to give recommendations and “manage” a process in which they know absolutely nothing.
- Look, comrades, what a wonderful city of Pripyat, the eye rejoices, - said the first secretary of the Kiev regional committee, making frequent pauses (before that, the discussion at the meeting was about the progress of the construction of the third power unit and the prospects for the construction of the entire nuclear power plant).- You say - four power units. And I will say this - not enough! I would build eight, twelve, or even all twenty nuclear power units here!.. And what ?! And the city will stretch out to a hundred thousand people. Not a city, but a fairy tale … You have a wonderful run-in team of nuclear builders and installers. Instead of opening a site in a new location, let's build here …
During one of his pauses, one of the designers intervened and said that the excessive accumulation of a large number of nuclear active zones in one place is fraught with serious consequences, because it reduces the nuclear security of the state both in the event of a military conflict and an attack on nuclear power plants, and in the case of ultimate nuclear accident …
A sensible remark went unnoticed, but Comrade Tsybulko's proposal was enthusiastically taken up as a directive.
Soon the construction of the third stage of the Chernobyl nuclear power plant began, the design of the fourth began …
However, on April 26, 1986, it was not far off, and the explosion of the nuclear reactor of the fourth power unit in one fell swoop knocked out four million kilowatts of installed capacity from the country's unified power system and stopped the construction of the fifth power unit, the commissioning of which was real in 1986.
Now let's imagine that V. M. Tsybulko's dream would have come true. If this happened, then on April 26, 1986, all twelve power units would be knocked out of the power system for a long time, the city with a population of one hundred thousand would be depopulated and the damage to the state would amount to not eight, but at least twenty billion rubles.
It should also be mentioned that power unit No. 4, designed by Gidroproekt, exploded, with an explosive solid-tight box and a bubbler pool under the nuclear reactor. At one time, as the chairman of the expert commission on this project, I categorically objected to such an arrangement and suggested by all means removing the explosive device from under the reactor. However, the expert opinion was then ignored. As life has shown, the explosion took place both in the reactor itself and in a solid-tight box … [.]
