Yuriy Chernichuk, Director of the Zaporizhia NPP, in a long interview with Russia’s Kommersant, described conditions at the plant and its future prospects. Currently, five of the plant’s six units with VVER-1000 reactors are in a cold shutdown, while one is in a hot shutdown to generate steam for the plant’s own needs.
Recently unit 4 was transferred from a hot to cold shutdown for repairs due to a water leak from a steam generator. Chernichuk said operators had identified a leak at from a pipe at the third steam generator and had decided to power it down to repair the defect. “An unpleasant situation, of course, for all operators, but nevertheless, this happens. Nothing terrible took place,” he said. “Since the unit 4 had to be taken out for repairs, we transferred unit 6 to a hot state. The procedure went smoothly. It was controlled and safe.” He explained that the difference between hot and cold shutdown is the temperature of the water that circulates through the reactor and fuel.
Asked whether there was a problem with operation of the steam generator he noted that recent operation had been “quite gentle”. However, he added: “But we must understand that the project for our station was developed in the mid-1970s and construction began in 1980. The steam generators, like all the other equipment, are already about 40 years old.” He explained that the working life of each component depended on the manufacturer and the designer but that the resources of the steam generator in question were quite large. “Leakage of the pipe part of steam generators is a common process that happens at almost all NPPs in the world, including in new facilities.”
Chernichuk, a former Chief Engineer at the plant, was appointed ZNPP Director at the end of November 2022. He said the appointment was unexpected. “I have worked at this station for 30 years in various positions, and the experience gained during this time was of great help to me. These years have not been in vain: I know this facility and the people here quite well. My experience helps me to carry the responsibility that I voluntarily shouldered.
Of course, most of the time I was at the station as a technical specialist, but I also have managerial experience. For about five years, I combined technical work and administrative functions.”
Asked about employees at the plant, he said they currently total around 4,000 with 1,000 applications from other candidates under consideration. “We continue to receive a large number of applications at our personnel department from our region, and also from other regions. We are optimistic about the personnel situation, although there are certain difficulties, of course.”
He elaborated: “We deliberately did not change the work schedule or rest periods of the staff, since they are not in a completely favourable psychological situation anyway. All station personnel work regularly: in the morning they take children to kindergartens and schools, then they come to work, and in the evening they go home. Station operators work in shifts – three eight-hour shifts each day.”
He said there was no shortage of critical personnel. “All critical positions for operational and decision-making personnel are filled. We can say with confidence that ZNPP complies with all the requirements for ensuring the safety of the plant, including in terms of personnel.” He added that Ukrainian citizens work at the plant authorised by a special Presidential decree ‘On the peculiarities of legal regulation in the field of the use of atomic energy in the territory of the Zaporozhye region’. This is permitted for a transitional period, until 1 January 2028.
Asked whether Russia’s Rosenergoatom had made any significant changes to the way ZNPP operated he explained that the plant was built in Soviet times and was similar to Russian plants at Balakovo, and Kalinin. “They were built and operated according to the same standards. After the collapse of the USSR, everyone began to live according to their own rules and norms, but there were no global radical changes in the approaches to operation and maintenance, apart from some nuances. We spoke the same language with the Rosenergoatom specialists from the first day, because we studied at the same schools and operated the same equipment.”
On interaction with IAEA experts, who have been present at the plant for almost a year, Chernichuk said they live on site and rules of interaction have been jointly agreed. “In the morning we meet with them to discuss the results of work over the past period, and plans for the coming days. When requested, we provide IAEA specialists with the opportunity to visit certain facilities at the station. They also visit unit control panels and communicate with operators. Experts monitor, record what is happening, and then this information is posted in the official publications of the IAEA…. We have no complaints about their publications. We have a working relationship with the head of the IAEA, Rafael Grossi. He was at the station three times, we always have constructive conversations and meetings.”
With respect to the destruction of the Kakhovka dam in early June, which drained the station’s reservoir, he said the plant was designed to cope with flooding and also with a possible decrease in the water levels in the reservoir. “However, as far as I know, the possibility of the complete destruction of the Kakhovskaya dam and the complete withdrawal of water were not considered.” Subsequently organisational and technical measures were taken to ensure the safety of the plant.
“In particular, we localised our cooling pond with additional technical devices, which provides the station with process water,” he noted. “Now the cooling pond does not depend on the Kakhovka reservoir, we maintain the water level as much as possible. So far we have no concerns. Even without the cooling pond, we will provide fuel cooling from other sources. We will not allow adverse situations. The station has alternative sources of water supply available and additional ones are being worked out”.
He added that the spray pools on the site were fully operational, and there are sources for replenishing these pools with water. We use artesian wells. “Now we have additionally developed a number of measures to search for and provide the station with alternative sources of water supply. We also have two cooling towers for additional water cooling. The existing system of cooling and water supply to the station is quite complex and extensive.”
Asked about accidents at the plant he said various scenarios had been developed and employees are constantly trained. “Naturally, no one wrote scenarios for combat situations on the territory of the station and around it. Nobody could have imagined that this could happen. ZNPP is the first plant in the world to end up in a war zone. But I can say with particular pride that the staff coped with all the challenges that fate threw at us. The station is in a safe condition and does not pose a threat to the surrounding territory and the population. However, the most terrible scenarios are hard to predict: it is impossible to predict the actions of the enemy. Let me remind you that there were precedents for shelling both our civilian infrastructure and auxiliary facilities of the station. This cannot be ruled out.”
Chernichuk noted that the fuel, reactors and all primary circuit equipment were protected by a thick reinforced concrete cylinder with a number of technical measures to enhance its strength.
As to the state of power transmission lines some of these are damaged in neighbouring regions. “We are on the front line, so the possibility of effects on the lines is very high. Since autumn, we have been using power lines only for power consumption for the station's own needs.”
The plant is well supplied with diesel generators. “There are 20 diesel generators at the site: three generators for each unit plus two general station ones to meet station needs,” he explained. “Maintenance, inspections and repairs of all equipment, including diesel generators, are carried out at the station according to schedule. Since the summer of 2022, the station has lost external power supply eight times and switched to powering its needs from diesel generators. The generators did not let us down, despite the fact that they are also 40 years old.”
Asked about major repairs to the station and its infrastructure and the possibility of restarting power generation, Chernichuk said; “You can talk about major events only after the end of hostilities. We at the station are both technically and organisationally ready to carry out any type of repairs. We are also ready to deploy any of the six units in the shortest possible time and put them into operation to supply energy to the grid. But it will take at least a year to restore the station's work in full. We depend on many external factors.”
Image: Yuriy Chernichuk, Director of Zaporizhia NPP (courtesy of Rosatom)