Ukraine’s Zaporizhia NPP (ZNPP) has for several days depended on a single power line for the off-site electricity it needs to cool its six reactors and for other essential nuclear safety and security functions, International Atomic Energy Agency (IAEA) Director General Rafael Mariano Grossi said in his latest update. This leaves it highly vulnerable to any further grid disruptions during the military conflict.
The site’s fragile power supplies continue to be at the centre of concern regarding nuclear safety and security, underlined by the site’s recent eighth complete loss of external electricity after the separate connections to both of its remaining power lines were cut, apparently caused by external grid events outside the ZNPP. As a result, the plant temporarily relied on emergency diesel generators for power.
It regained the connection to its main 750 kilovolt (kV) line after nearly five hours, but its last 330 kV back-up power line is still disconnected. The IAEA experts at the ZNPP have been informed that the repairs are expected to be completed by early next week. Before the conflict, the ZNPP had four 750 kV lines as well as several back-up options available.
The IAEA team also reported that reactor 4 – whose main cooling pumps briefly stopped running during last week’s external power loss – is once again in hot shutdown mode producing heating and steam for the site and the nearby town of Energodar, where most plant staff live. The other five reactors remain in cold shutdown.
“The IAEA remains fully focused on doing everything it can to help prevent a nuclear accident during this devastating war. The repeated loss of off-site power at the Zaporizhia NPP, sometimes from causes at a considerable distance from the plant, remains one of our main challenges in this context, especially during the winter months. No one would gain from a nuclear accident and it must be avoided,” Grossi said. Although ZNPP has previously relied on one sole external power line, it is clearly not a sustainable situation, he added.
A new team of IAEA experts recently crossed the frontline to replace their colleagues who had been monitoring nuclear safety and security at the ZNPP for the past several weeks. It is the fourteenth IAEA team at the site since the IAEA Support & Assistance Mission to the ZNPP was established in September 2022.
The new team of IAEA experts will continue to pay close attention to the staffing situation at the ZNPP, the status of the external power supply as well as maintenance activities at the site, including any actions the plant may take following last month’s detection of boron in the secondary circuit of a steam generator of unit 5. Borated water is used in the primary coolant to help maintain nuclear safety functions.
In a reminder of the physical proximity of the conflict to the ZNPP, the IAEA experts continue to hear explosions in the distance, likely from heavy artillery and rockets. The new team reported that they heard nine explosions closer to the site.
The IAEA team also conducted a walkdown of the turbine halls of all six reactor units. The experts did not observe any mines, explosives, military equipment or vehicles in the areas they visited. Not all parts of the turbine halls were accessed so additional access would be required to fully assess whether there were any items present that could potentially impact nuclear safety.
Russia’s Defence Ministry said for the latest IAEA rotation, security was provided by Russia. A ceasefire regime was declared along the route, which was strictly observed by all Russian servicemen. Before the start of the movement, Russian sappers examined the territory for the presence of unexploded Ukrainian and foreign ammunition left after the shelling of the territory.
Zaporizhia NPP specialists have signed a collective labour agreement. The document provides for social guarantees for the protection of labour rights, health and recreation of employees and their children. "The employment contract is an important achievement, it is the key to the stability of the labour collective, said ZNPP Director Yuriy Chernichuk. “A lot of work is being done at ZNPP to ensure the labour rights of nuclear workers and all social obligations. The policy of strengthening and developing socially-oriented potential will continue."
In addition, the contract contains requirements for providing professional training, retraining and advanced training of personnel. There are also requirements for social benefits and support for large families, war veterans and unemployed pensioners. The collective agreement is valid for three years and can be extended for a maximum of three years.
