At Ukraine's Zaporizhzhya Nuclear Power Plant (ZNPP), repairs are being conducted in one of its six reactors after a small water leakage was detected from an impulse line - essentially a small pipe - connected to the unit's primary circuit, with the work expected to be completed later this week, Director General Rafael Mariano Grossi of the International Atomic Energy Agency (IAEA) said today.
The IAEA expert team stationed at the ZNPP visited unit 1 on Tuesday after being informed that one of the impulse lines, part of the reactor coolant pump support systems, was leaking and required repair. For this work, the pressure in the primary circuit had to be decreased to atmospheric level. The team was informed today that welding work had been completed and that radiography checks of the welds were on-going.
"The Agency will continue to follow this issue closely, although we don't see any immediate issue for nuclear safety. In general, we have identified regular equipment maintenance - which is vital to ensure sustainable nuclear safety and security - as a challenging area for the Zaporizhzhya Nuclear Power Plant during the conflict," Director General Grossi said.
Like the ZNPP's five other reactors, unit 1 has been in cold shutdown, generating no electricity for the grid, prior to this week's change in status to shutdown for maintenance. It is expected that unit 1 will be put back to cold shutdown after the repair of the impulse line is completed and tested.
The IAEA team has also carried out other walkdowns during the past week as part of their continuous work to assess - and report on - nuclear safety and security at the ZNPP, where the general situation remains precarious on the frontline of the conflict.
Earlier this week, for example, the team visited the main control rooms of all six units to examine key plant parameters as well as the staffing situation. The IAEA staff have also visited some of the emergency diesel generators (EDG) of units 2 and 5 to verify the readiness of equipment and check the diesel fuel levels.
As virtually every week, the team has continued to hear explosions daily, although no damage to the plant was reported.
Elsewhere in Ukraine, an IAEA team last week completed its visits to seven electrical substations, as part of the Agency's work to assess the status of the electrical grid infrastructure essential to nuclear safety that began in September.
During the visits, which were requested by Ukraine, the team reviewed how damage caused by military activities earlier this year had impacted the substations' deliveries of off-site power to the country's operating nuclear power plants (NPPs), an area highlighted in the Seven Indispensable Pillars of nuclear safety and security outlined by Director General Grossi in March 2022.
The IAEA teams present at the Khmelnytskyy, Rivne and South Ukraine NPPs and the Chornobyl site reported that nuclear safety and security is being maintained despite the effects of the ongoing conflict, including air raid alarms for several days over the past week.
On Monday, the team at the Khmelnytskyy NPP had to shelter at their hotel for several hours after hearing drones which triggered an air raid alarm. The IAEA was subsequently informed by the Ukrainian regulator that 12 drones had been flying near the site during the morning, the closest 400 metres away. The regulator also said drones had been reported near the South Ukraine site on three occasions over the past week.
"Frequent reports of drones flying near nuclear power plants continue to be a source of deep concern for nuclear safety and security. As we have stated repeatedly, any military activity in the vicinity of nuclear power plants represents a potential risk," Director General Grossi said.
The IAEA is continuing to implement its comprehensive programme of assistance in support of nuclear safety and security in Ukraine, including by delivering requested equipment.
Over the past two weeks, the South Ukraine NPP received radiation and contamination monitoring devices, while State Enterprise USIE Izotop - involved in the management of radioactive material intended for medical, industrial and other purposes - received personal protective equipment. These items were procured with funds from Japan, Switzerland and the United Kingdom. So far, a total of 73 deliveries of equipment and other supplies have been completed by the IAEA.
Last week, remote training on human performance and management observation and coaching was completed for 109 staff at the Chornobyl, Rivne and South Ukraine sites. The training aimed to equip staff and management with skills on how to prevent or reduce the risk of human errors with potential implications for nuclear safety.
