In a long address to the UN Security Council (UNSC), International Atomic Energy Agency (IAEA) Director General Rafael Mariano Grossi said the security situation at the Zaporizhia NPP (ZNPP) continues to be “extremely fragile”. It was his sixth address to the UNSC since the start of Russia’s special military operation in Ukraine in February 2022.
Shortly after the start of the conflict he elaborated Seven Indispensable Pillars for ensuring nuclear safety and security during an armed conflict. These are:
- The physical integrity of facilities must be maintained.
- All safety and security systems and equipment must be fully functional at all times.
- Operating staff must be able to fulfil their duties free of undue pressure.
- There must be a secure off-site power supply from the grid for all nuclear sites.
- There must be uninterrupted logistical supply chains and transportation to and from the sites.
- There must be effective on-site and off-site radiation monitoring systems, and emergency preparedness and response measures.
- There must be reliable communication with the regulator and others.
Grossi recalled that as a result of intensive consultations with both Ukraineand Russia he had established five concrete principles for the ZNPP in order to prevent a nuclear accident and ensure the integrity of the plant, namely:
- There should be no attack of any kind from or against the plant, in particular targeting the reactors, spent fuel storage, other critical infrastructure, or personnel;
- ZNPP should not be used as storage or a base for heavy weapons or military personnel that could be used for an attack from the plant;
- Off-site power to the plant should not be put at risk and all efforts should be made to ensure that off-site power remains available and secure at all times;
- All structures, systems and components essential to the safe and secure operation of ZNPP should be protected from attacks or acts of sabotage;
- No action should be taken that undermines these principles.
These principles had received UNSC support in May 2023 and experts on the IAEA Support & Assistance Mission to Zaporizhia (ISAMZ), on-site since 1 September 2022, regularly report on observance of these principles.
Grossi noted he had personally led eight of 102 IAEA missions to Ukraine, including three to ZNPP and that he would shortly be leading another to ZNPP within the next two weeks, where the 15th ISAMZ team was working. He said 37 IAEA staff had been part of these missions, a number of them more than once.
IAEA also has IAEA experts stationed at every major Ukrainian nuclear site: Rivne NPP, South Ukraine NPP, Khmelnytsky NPP and at the Chornobyl on the nuclear safety and security situation at each of those sites as well. More than 100 of IAEA staff have been part of these teams, totalling more than 3,662 person-days. IAEA continues to facilitate an international assistance package now totalling more than €8.5m ($9.2m) including 34 deliveries of vital equipment to Ukraine and is “proposing to provide advice, training, and equipment in the area of the safety and security of radioactive sources in Ukraine”.
IAEA had also “put together a programme of health care assistance including through equipment and psychological support for all Ukrainian nuclear workers,” Grossi added. “I also announced the new programme for assistance of the Kherson Oblast aimed at managing the adverse impact associated with the flooding after the Kakhovka dam destruction and we work with Ukraine to identify their immediate needs in this area.” IAEA is also continuing safeguards verification activities across Ukraine, ensuring that there is no diversion of nuclear material for military purposes.
With respect to ZNPP, Grossi said the potential dangers of a major nuclear accident remain very real. The plant’s six reactors have been shut down since mid-2022 – five in cold shutdown and one in hot shutdown. “Although the plant has not been shelled for a considerable time, significant military activities continue in the region and sometime in the vicinity of the facility, with our staff reporting rockets flying overhead close to the plant, thereby putting at risk the physical integrity of the plant.”
The plant needs secure and uninterrupted sources of external cooling water. “The destruction of the Kakhovka dam in early June last year, just days after I last reported to the Council, led to a large reduction in the water level of the reservoir,” he said. “Consequently, the depth of the water in the reservoir was no longer sufficient to supply water and considerable efforts on site were needed, including the drilling of wells on site, to provide sufficient cooling water for the six shutdown reactor units.”
In addition, the plant has been operating on significantly reduced staff, who are under unprecedented psychological pressure – “which despite the reactors being shut-down is not sustainable”. The reduced number of qualified and trained operating personnel and the challenging supply chain has had a negative impact on the maintenance of equipment which is essential for maintaining the safety of the plant.
Grossi recalled that there have been eight occasions when the site lost all off-site power and had to rely on emergency diesel generators to provide essential cooling of the reactor and used fuel. “The plant is currently relying on just two lines of external power, and sometimes just one, or for a period the backup power was not properly configured. This demonstrates the highly precarious situation regarding essential off-site power.”
He noted that there have been occasions when the IAEA team has not had timely access to some areas of the plant. “The IAEA teams need access in order to be able to effectively conduct their assessment of the situation regarding nuclear safety and security at the ZNPP and to reflect on the new developments.”
Grossi concluded: “A nuclear accident has not yet happened. This is true. But complacency could still lead us to tragedy. That should not happen. We must do everything in our power to minimise the risk that it does. And I am grateful for the continuing support from member states - including financial support.”
As to the five principles established earlier, Grossi stressed that they are not an arms control or armistice agreement. “They are not the solution to all the tragic problems this war has brought. Instead, they are a creative, practical arrangement which has a very defined aim: to save Ukraine, Europe, and the world from a major nuclear accident with significant radiological consequences. So far, this limited but crucial objective has been achieved. But we should not be complacent – we should take nothing for granted. Utmost restraint is a must, from all sides.” He asked for continued UNSC support.
During a press conference after the UNSC meeting Grossi was asked about the causes of the power outages at ZNPP. “Some may be caused by events taking place hundreds of kilometres from the plant, which may be deliberate – I’m not saying is just an unwitting result,” he said. “The forces in place know very well which are the lines feeding the plant.” He noted that during his forthcoming visit to ZNPP he would be leading the 16th rotation of the ISAMZ team after which he would be going to Russia for “political and technical dialogue”.
In its latest update on the situation at ZNPP, IAEA noted that one of the plant’s back-up power electrical transformers that had failed the previous week was under maintenance and that there were no indications of structural damage. ZNPP said it had investigated and identified the preliminary cause of the failure, and the IAEA experts are expecting to be informed of the outcome in the near future.
Also, IAEA experts had conducted a walkdown of the cooling pond area and met with plant staff handling the site’s water management to discuss the effects of the cold winter weather and how the ZNPP deals with any impact of ice. Prior to the conflict, the water in the cooling pond was kept warm due to the operation of the reactor units. With all six units now in extended shutdown, the IAEA team observed small amounts of ice in a few locations of the cooling pond. However, earlier this winter most of the cooling pond surface was covered by a two-centimetre layer of ice, the site informed the IAEA team. Nevertheless, there are a lot of fish in the cooling pond. Several non-tropical fish species have survived the cold temperatures and continue to clean the cooling pond water.
The height of the cooling pond currently is at 15.61 metres, around one metre below the level before the Kakhovka dam was destroyed with little change in the height over recent months. The cooling water for the six shutdown reactors continues to be supplied by the 11 groundwater wells near the sprinkler ponds. The IAEA experts were not permitted to visit the ZNPP cooling pond isolation gate during the walkdown.
During other recent walkdowns, IAEA experts visited the reactor hall of unit 3, as well as the safety systems rooms of units 3&5. A single small boric acid deposit was observed in one of the safety systems rooms of unit 3. Regarding boric acid deposits in unit 6, the Russian regulatory body had issued a “special order” on 20 January for the repair of a leak in the unit’s storage tank. ZNPP plans to fix the microcracks in the tank, which will require its draining. Borated water is used in the primary coolant to help maintain nuclear safety functions.
The IAEA team also conducted a walkdown of the 750 kilovolt (kV) open switchyard where it confirmed that only one such power line was connected to the electricity grid – down from four before the conflict. The switchyard components that were damaged in 2022 had been dismantled, but spare parts were available.
Image: Rafael Mariano Grossi, Director General of the International Atomic Energy Agency (courtesy of IAEA)
