Ukraine’s Zaporizhzhya Nuclear Power Plant (ZNPP) still has enough essential staff for its current reduced level of operations, but the continued lack of maintenance personnel on-site could negatively impact nuclear safety and security and is not sustainable, Director General Rafael Mariano Grossi of the International Atomic Energy Agency (IAEA) said today.
Europe’s largest nuclear power plant (NPP) – located by the frontline – has seen a considerable reduction in staffing numbers since the armed conflict in Ukraine began nearly 15 months ago. Concerns about the difficult and challenging circumstances for plant personnel and their families have deepened further amid signs of a growing military presence and activity in the region.
“It is not sustainable to maintain this major nuclear power plant for extended periods with only essential staffing. The safety of the plant, even in a shutdown state, requires adequate maintenance of plant equipment, as well as other regular and important work. It is concerning that the established maintenance programme was not followed for many months now,” Director General Grossi said.
Last week, IAEA experts at the ZNPP learnt that a voluntary evacuation of residents from the nearby town of Enerhodar – where most plant personnel live – had begun, creating further uncertainty about the staffing situation.
The IAEA team observed that there have been fewer staff on-site over the past week, but they were still able to confirm that essential personnel working in the main control rooms were available and present during each shift.
The IAEA experts were informed that the past week’s reduced number of staff was due to the recent holiday period and the current situation in the region, with plant management adding that it remained a priority to have sufficient staff to meet all relevant regulatory requirements, including those for nuclear and industrial safety.
Director General Grossi expressed concern that the challenging staffing situation could affect the ZNPP’s ability to properly maintain systems that are important for nuclear safety and security.
“In the medium and longer term, this is increasing the risk of a nuclear accident and its associated consequences for the population and the environment. There must be staff available to properly maintain the Zaporizhzhya Nuclear Power Plant and to ensure it remains in a safe state at all times,” he said.
The Director General – who has repeatedly expressed concern about the welfare of staff and their families and the potential impact on nuclear safety and security – said the IAEA team was closely monitoring developments and that the experts, in recent days, had visited Enerhodar, and also engaged with staff in the plant’s reactor control rooms and elsewhere.
“There is little doubt that the plant is experiencing a very difficult staffing situation. As the plant’s six reactors are all in a shutdown state – thereby requiring fewer operating staff – our assessment is that the current level of operating staff is sufficient, for now. But this is not a way to operate a major nuclear power plant safely, securely, and sustainably,” he said.
The IAEA team at the ZNPP has also previously reported about a significant impact on the plant’s maintenance capability due to reduced staff, absence of external contractors who performed part of the maintenance work in the past, and a lack of spare parts needed for the maintenance, including critical components.
Director General Grossi said he was increasingly concerned about nuclear safety and security in general at the ZNPP at a time of heightened speculation of future military operations in the area and elsewhere. The IAEA experts at the site have continued to hear shelling and gunfire.
“I remain engaged in intense negotiations with all the involved parties to secure the protection of the Zaporizhzhya Nuclear Power Plant. Everybody would lose if there were a nuclear accident that could have serious consequences for human health and the environment in Ukraine and beyond. Protecting the plant should be a clear win-win for all sides. I will not give up until this has been achieved,” Director General Grossi said.
Further underlining the nuclear safety and security risks, the ZNPP continues to rely on the only remaining functioning 750 kilovolt (kV) power line for the external electricity it needs for reactor cooling and other essential nuclear safety and security functions. Before the conflict, the plant had four such off-site power lines available. The last functioning back-up 330 kV power line that was damaged on the right bank of the Dnipro River on 1 March has still not been repaired.
The IAEA team continues to monitor the actions taken for restoring other sources of off-site power but has not had access to the nearby Zaporizhzhya Thermal Power Plant (ZTPP), despite assurances by Rosatom that this would be granted. The ZTPP operates its 330 kV open switchyard, through which back-up power has in the past been provided to the ZNPP. Director General Grossi underlined the importance of the IAEA gaining access to the ZTPP as soon as possible.
The IAEA experts also monitor the height of the Kakhovka Reservoir. The height of the reservoir has risen significantly over the past month and on 6 May it was at historically high levels of 17.12 metres, which had raised concerns that the high levels could adversely affect the plant. The height is currently 17.07 metres. The elevation of the ZNPP site is 22 metres, approximately five metres above the current height of the reservoir. The possible effects on the plant from flooding were analysed as part of stress tests conducted following the Fukushima Daiichi accident in 2011. Based on the conservative scenario of all upstream dams failing, the analysis demonstrated that the water levels could reach 19.6 metres, still below the site elevation. At water heights above 17.7 metres, water from the reservoir would flow directly into the cooling pond of ZNPP. This could adversely affect the quality of the cooling water but would not affect the nuclear safety of the plant.
In addition, if the height of the reservoir were to continue to rise to such a level that the Kakhovka Dam, located approximately 100 kilometres downstream from the ZNPP, was no longer able to retain water, then the water levels near ZNPP and the near-by town and villages would decrease. Nevertheless, the IAEA assesses that this reduction in water levels would not pose any immediate threat to nuclear safety and security, and would be similar to the situation reported in Update 145.
IAEA experts are also permanently present at Ukraine’s other NPPs – Khmelnitsky, Rivne and South Ukraine – and the Chornobyl site, helping Ukraine maintain nuclear safety and security during the conflict. After several weeks of relative calm, our teams reported frequent air raid alarms earlier this week.
On 1 May, the 16th delivery of equipment to Ukraine took place as part of the IAEA’s overall efforts to help maintain nuclear safety and security in Ukraine. It comprised IT equipment for the Ukrainian Hydrometeorological Centre intended to strengthen its capability for radiation monitoring, storing of data as well as sharing of data internationally through the IAEA IRMIS (International Radiation Monitoring Information System) website. Also, 200 Portable Power Systems for the Public Health Centre of the Ministry of Health in Ukraine were delivered in order to compensate for the frequent power losses. The equipment was procured by the Agency using an extrabudgetary contribution from Australia.
On 5 May, the IAEA signed an agreement with France and Ukraine’s Energoatom regarding support to Ukraine’s NPPs. Through this agreement, Ukraine will receive the necessary spare parts for emergency diesel generators of the South Ukraine NPP. In case of loss of off-site power, the NPPs rely on their emergency diesel generators to provide power for their continued safe and secure operation until off-site power is restored. Therefore, the maintenance and functionality of the emergency diesel generators, including the availability of spare parts, is essential to ensure their proper functioning to prevent a nuclear accident due loss of off-site power.