Category: Nuclear Control

Source: International Atomic Energy Agency – IAEA

International Atomic Energy Agency (IAEA) experts based in Ukraine reported about military activity overnight that once again underlined potential nuclear safety and security dangers during the armed conflict, and not just at the Zaporizhzhya Nuclear Power Plant (ZNPP), Director General Rafael Mariano Grossi said today.

In western Ukraine, an IAEA team monitoring the situation at the Khmelnitsky Nuclear Power Plant (NPP) reported hearing several explosions in close proximity, over a 20-minute period late last night while in their quarters.

Even though the plant was not directly affected, the incident showed that all of Ukraine’s nuclear power plants remain at risk as long as the war continues, Director General Grossi said.

“Much of the world’s attention – and rightly so – is focused on the very real dangers facing the Zaporizhzhya Nuclear Power Plant, which is of special concern as it is located on the frontline. But last night’s event serves as a reminder that we must not forget about the other nuclear sites in Ukraine, which are also potentially exposed to missile and other attacks,” Director General Grossi said.

“All of Ukraine’s nuclear facilities remain vulnerable, either directly if hit by a missile or indirectly if their off-site power supplies are disrupted. There continues to be a highly precarious nuclear safety and security situation across Ukraine,” he said.

At the ZNPP today, the team also reported an air raid warning at the site that lasted for about ten minutes in the afternoon. There was no impact heard by the team during the air raid warning, and there was no damage to the site. Over the last 24 hours, the IAEA team has continued to hear the sound of explosions some distance from the plant.  

At the other Ukrainian nuclear facilities where the IAEA has permanent teams – the Rivne NPP, South Ukraine NPP and Chornobyl site – the IAEA teams did not report hearing any military activities.

Source: International Atomic Energy Agency – IAEA

The main power line supplying electricity to Ukraine’s Zaporizhzhya Nuclear Power Plant (ZNPP) has been restored after a sudden cut in the connection during the weekend, the latest reminder of the fragile nuclear safety and security situation at the site during the ongoing military conflict, Director General Rafael Mariano Grossi said today.

Underlining the potential dangers Europe’s biggest nuclear power plant is continuing to face, the IAEA experts present at the facility heard – for a second time in the past few days – the distinctive sound of several rockets that appeared to have been fired from close to the plant. Also today, the team heard multiple artillery rounds which also seemed to have been fired from near the ZNPP.

Director General Grossi said the apparent military action in the vicinity of the plant could heighten the nuclear safety and security risks at the site and potentially undermine the five concrete principles for the protection of the ZNPP that he presented at the United Nations Security Council in May earlier this year.

“I call on all sides to exercise utmost restraint at or near the Zaporizhzhya Nuclear Power Plant. No one would gain a military advantage from causing a nuclear accident during this terrible war, on the contrary,” he said. “The troubling events of recent days – with rockets launched from close to this major nuclear power plant – are further deepening our nuclear safety and security concerns.”

In a separate development, the ZNPP’s single remaining 750 kilovolt (kV) power line is again able to deliver the external electricity the plant needs for reactor cooling and other essential nuclear safety and security functions. The connection was lost on Sunday morning after a short circuit that reportedly occurred around 100 kilometres north of the site, but the power line connection was restored later the same evening.

During the time when the 750 kV line was disconnected, the ZNPP received off-site electricity from the only remaining 330 kV back-up power line. This means that there are once again two independent power lines essential for delivering external power to the plant.

“The plant’s vulnerable off-site power supplies remain one of our main concerns when it comes to nuclear safety and security in Ukraine. As we have experienced multiple times, including last winter, attacks far away from the site can cause severe disruptions in the electricity grid that also serves the Zaporizhzhya Nuclear Power Plant. All military action that could endanger nuclear safety and security must be avoided,” Director General Grossi said.

Source: International Atomic Energy Agency – IAEA

Ukraine’s Zaporizhzhya Nuclear Power Plant (ZNPP) lost the connection to its main off-site power line today, forcing it to rely on back-up electricity for reactor cooling in the latest incident underlining the precarious nuclear safety and security situation at the site during the ongoing military conflict, Director General Rafael Mariano Grossi said.

Separately today, the IAEA experts present at the ZNPP heard several rockets that appeared to have been fired from close to the plant. The IAEA team did not see the projectiles because of clouds but the distinctive sound indicated they were fired from a Multiple Launch Rocket System (MLRS) nearby.

“Today’s events once again clearly demonstrate the extremely fragile nuclear safety and security situation at the Zaporizhzhya Nuclear Power Plant. Europe’s largest nuclear power plant – located on the frontline – continues to face many potential threats as a result of this tragic war,” Director General Grossi said.

“I remain deeply concerned about nuclear safety and security at the plant, both when it comes to its vulnerable off-site power supplies – which can be affected by attacks far away from the site – and the more direct military risks it is facing, potentially undermining the principles that I set out at the United Nations Security Council in May. In this context, the apparent firing of rockets from near the plant is a special source of concern,” he said.

The ZNPP said a short circuit that occurred around 100 kilometres north of the plant caused the cut in the connection to its sole remaining 750 kilovolt (kV) power line – out of the four that existed before the conflict – at around 10:30am local time.

The plant continues to receive external power from its only available 330 kV back-up power line. However, one emergency diesel generator also started operating to supply reactor unit 4 after the power loss, indicating a possible issue with its electrical configuration. The diesel generator was manually shut down after ten minutes.

The plant said the 750 kV line is being repaired but it was not clear when it will be reconnected.

The ZNPP has lost external power supplies repeatedly during the conflict, including seven complete loss of off-site power events. On each of those occasions, the operation of emergency diesel generators at the site was required to provide the electricity needed by the plant for vital nuclear safety and security functions, including reactor cooling. The connection to the 750 kV line was last lost on 10 August, when the line disconnected and was reconnected twice on the same day.

Source: International Atomic Energy Agency – IAEA

International Atomic Energy Agency (IAEA) experts observed an emergency exercise conducted at  Ukraine’s Zaporizhzhya Nuclear Power Plant (ZNPP) this week, the latest such drill in the country’s nuclear facilities during the military conflict, Director General Rafael Mariano Grossi said today.

Thursday’s exercise focused on actions that should be taken in response to a hypothetical break of a pipe containing radioactive wastewater and the disconnection of power from one reactor unit.

The IAEA experts followed the two-hour exercise from the ZNPP’s temporary emergency centre, observing the coordination of emergency response actions. They also observed field activities during the exercise, including radiation and contamination monitoring as well as preparations for the evacuation of some plant staff. After the exercise was completed, the IAEA team observed the standard debriefing. Overall, the IAEA experts said the exercise scenario was carried out as planned.

Last week, the IAEA team based at Ukraine’s Rivne Nuclear Power Plant (NPP) observed an emergency exercise at that site. Also this week, the IAEA team at the Chornobyl site observed an emergency drill at the radioactive liquid waste treatment plant.

“Having effective emergency preparedness and response arrangements is one of the seven indispensable pillars for ensuring nuclear safety and security in an armed conflict. It is vital that the Zaporizhzhya Nuclear Power Plant tests its emergency response arrangements. We encourage  the plants in Ukraine to conduct more exercises in future to further test their emergency preparedness,” Director General Grossi said.

The ZNPP has throughout the conflict been at the centre of the IAEA’s concerns about nuclear safety and security in Ukraine. It is located on the frontline and has lost all off-site power as many as seven times. Director General Grossi told the IAEA Board of Governors on Wednesday that the situation at the plant remained challenging, with six out of the seven pillars of nuclear safety and security during an armed conflict “compromised either fully or partially”.

Earlier this week, the ZNPP’s unit 5 reached cold shutdown, leaving one of the plant’s six reactors in hot shutdown to produce steam and heating. The plant decided to move the unit from hot shutdown after boron was detected in a secondary cooling circuit, albeit at levels below the limits set by its technical specifications. No radioactivity has been detected in the secondary cooling circuit. Borated water is used in the primary coolant to help maintain nuclear safety functions.

After the cold shutdown state was reached at unit 5, the ZNPP informed the IAEA team that it will not immediately investigate the cause of the presence of boron in the secondary cooling circuit of one of the unit’s steam generators. The IAEA experts will continue to monitor this issue during its discussions with ZNPP and walkdowns of the plant. 

The IAEA experts are also continuing to gather information to fully understand why unit 6 temporarily lost power on 14 November and relied on a diesel generator for 90 minutes. They held multiple discussions on this issue with the ZNPP’s electrical department this week.

Unit 4 remains in hot shutdown to provide steam for nuclear safety related activities at the ZNPP and also for heating at the site and the nearby town of Enerhodar, where most plant staff live. Additional heating is provided by mobile diesel boilers installed at the ZNPP together with boilers located in the nearby industrial zone. Reactor units 1, 2, 3, 5 and 6 are now in cold shutdown.

Elsewhere in Ukraine, the IAEA experts at the Chornobyl site have successfully conducted a planned rotation today, with a new team arriving from headquarters in Vienna.

The IAEA teams at the Khmelnitsky, Rivne and South Ukraine NPPs and the Chornobyl site report safe and secure operations of these nuclear facilities despite the continuation of the conflict.

Source: International Atomic Energy Agency – IAEA

An International Atomic Energy Agency (IAEA) team of experts said that the operator of the Beloyarsk Nuclear Power Plant (NPP) in the Russian Federation has shown a commitment to enhancing operational safety. The team also encouraged the operator to further improve safety in areas including accident management and safety assessments.

Requested by the Government of Russian Federation, the Operational Safety Review Team (OSART) mission ran from 6 to 23 November. The Team reviewed operational safety in Unit 4 of the Beloyarsk NPP.

OSART missions independently assesses safety performance against the IAEA’s safety standards. The aim is to advance operational safety by proposing recommendations and, where appropriate, suggestions for improvement. Safety is an essential element during commissioning and the subsequent safe operation of a nuclear power plant.

The Beloyarsk NPP is located at Zarechny, in the Sverdlovsk region, roughly 1800 kilometres east of Moscow. The plant is owned by State Atomic Energy Corporation Rosatom (ROSATOM) and operated by Beloyarsk NPP, a subsidy of the Rosenergoatom Joint Stock Company. The plant consists of four units. Units 1 and 2 – both light water graphite reactors – are permanently shutdown. Units 3 and 4 are two fast neutron reactors with gross electrical capacity of 600 and 885 megawatt electrical (MW(e)), respectively. Russia has 37 nuclear power reactors in operation, providing almost 20 per cent of the country’s total electrical production. 

The team reviewed operating practices in Unit 4 in the areas of leadership and management for safety, training and qualification, operations, maintenance, technical support, radiation protection, chemistry and accident management. The team was composed of six experts from Armenia, Belarus, China and the Islamic Republic of Iran, as well as four IAEA staff members and three observers from Russia.

To make its assessment, the team reviewed documents from the Beloyarsk plant on its main technical features, staff organization and responsibilities, and its operational programmes, procedures and performance prior to the mission. During the mission, the team observed the plant in operation, examined indicators of its performance and held in-depth discussions with plant personnel.

The OSART team observed that the staff at the plant are knowledgeable and professional, and are committed to improving the operational safety and reliability of the plant. The team said that the technical exchanges with the plant’s staff were fruitful and that there was a good exchange of experience and knowledge on how the common goal of excellence in operational safety could be further enhanced.

The team identified one area of good practice to be shared with the nuclear industry globally. They said the connection used by the plant to sample gases in the reactor circuit minimizes the potential for impurities to impact the gas analysis, whilst ensuring that the gas does not escape into the work area.

The mission also provided some suggestions to further improve safety, including that:

• The plant should consider enhancing its accident management programme to include the full range of ‘beyond design’ external hazards for all modes and states of operation and all fuel locations on site.
• The plant should consider extending the scope of its probabilistic safety assessments (PSA) to ensure that all potential failure scenarios are identified to cover all operational modes, all fuel locations on site as well as the full spectrum of external hazards.
• The plant should consider improving the effectiveness of the checks carried out during field operator walkdowns, so all deficiencies and adverse conditions are identified to ensure safe and reliable operation of plant structures, systems and components.

“It is the first time an IAEA OSART mission was held at the power unit of a BN-800 fast neutron reactor,” said Ivan Sidorov, Director of Beloyarsk NPP. “For three weeks, the reviewers and the counterparts have worked hard, performing dozens of plant tours, interviews and observations, and analysing plant documentation for all reviewing areas. We appreciate the reviewers’ professional point of view, and we are ready to learn from their experience to improve safety at Beloyarsk NPP.”

The team provided a draft report of the mission to the plant management. They will have the opportunity to make factual comments on the draft. These comments will be reviewed by the IAEA, and the final report will be submitted to the Government within three months.

Background

General information about OSART missions can be found on the IAEA website. An OSART mission is designed as a review of programmes and activities essential to operational safety. It is not a regulatory inspection, nor is it a design review or a substitute for an exhaustive assessment of the plant’s overall safety status.

Follow-up missions are standard components of the OSART programme and are typically conducted within two years of the initial mission.

The IAEA Safety Standards provide a robust framework of fundamental principles, requirements and guidance to ensure safety. They reflect an international consensus and serve as a global reference for protecting people and the environment from the harmful effects of ionizing radiation.