Update 361 – Iaea Director General Statement On Situation In Ukraine

A recent rise in off-site power losses at the Zaporizhzhya Nuclear Power Plant (ZNPP) highlights the fragility of the electrical grid serving the site and the need for continued efforts to help prevent a nuclear accident during the military conflict, Director General Rafael Mariano Grossi of the International Atomic Energy Agency (IAEA) said today.

The ZNPP has lost access to external power twice in the past week, bringing the total number of such events since the conflict began to 24. Twelve of these have occurred in the past four months alone.

On 1 August and again on 4 August, the ZNPP lost connection to its sole remaining off-site power line, the 330 kilovolt (kV) Ferosplavna-1 line, for brief periods. In both cases, the site’s available emergency diesel generators started operating automatically and provided power to the plant’s vital safety systems, including for reactor cooling.

The Ferosplavna-1 line reconnected automatically shortly afterwards, and the losses of off-site power were over within about two hours and one hour, respectively. The direct causes of the disconnections are not yet known.

“This trend, with the rising number of off-site power cuts at the Zaporizhzhya Nuclear Power Plant, is deeply concerning and clearly not sustainable. The Agency will continue its work to help improve the situation and support nuclear safety and security at the site,” Director General Grossi said.

A key challenge for the stability of the national grid remains the availability of operational electrical substations, which function as critical hubs in the electricity network and are essential for maintaining reliable off-site power to the ZNPP as well as Ukraine’s other nuclear power facilities, three of which are operating to produce electricity for the grid.

Late last week, the Agency completed its latest mission – the eighth of its kind – to substations that are essential for nuclear safety in Ukraine. The mission team visited 13 substations across the country to assess and document damage caused by military attacks, including any damage sustained since previous IAEA visits, and to evaluate the impact on the safe operation of Ukraine’s nuclear power plants (NPPs).

The ZNPP has been without its main external power line, the 750 kV Dniprovska line, since March this year. The line was initially unavailable because of damage caused by military activity and was repaired in early June under an IAEA-brokered ceasefire. However, it remains unavailable because the substation that provides power to the line was heavily damaged by military strikes in May.

“These substation missions have a clear nuclear safety and security purpose. As set out in the seven indispensable pillars, nuclear power plants require reliable off-site power, and substations are a crucial part of that process,” Director General Grossi said.

In another development, the IAEA team at the ZNPP was informed late last week that the site has decided to raise the water levels in the spent fuel pools of all six reactor units. The measure is intended to increase the time available before water could begin to boil off in the event of a prolonged loss of off-site power during which the site exhausted its diesel fuel supplies and could no longer continue cooling the pools.

The decision was taken in light of the prolonged unavailability of the 750 kV Dniprovska line and current challenges in resupplying the site’s diesel fuel stores because of military activity in the area. The work began this week, with the IAEA team present to observe.

The IAEA team at the ZNPP continues to report hearing military activity, including explosions, several times a day, often at distances close to the site. The plant has also continued to report military activities in the nearby city of Enerhodar, where many plant staff live, as well as drone activities in and around the site.

At the South Ukraine NPP, the site continued to report air raid alarms on a near-daily basis. It also reported detecting one drone within its monitoring area early on Wednesday, as well as another earlier this week.

At the Chornobyl NPP, the site also continues to report frequent air raid alarms and detected three drones within its monitoring area over the past weekend.

“With each new day of the conflict, the risks to nuclear safety and security are not decreasing, on the contrary. I renew my call for maximum military restraint around all of Ukraine’s nuclear power plants and their associated electrical infrastructure,” Director General Grossi said.

As part of the IAEA’s assistance programme for Ukraine, a high-performance laptop was delivered to the Chornobyl NPP, strengthening its technical and analytical capacity. It also received one high-sensitivity industrial video camera intended for remote monitoring of spent nuclear fuel handling operations in high-radiation areas. The National Scientific Center ‘Institute of Metrology’ received a remote grab device and mechanical chain hoist, supporting the safe handling of equipment and materials.

In addition, one mobile radiation monitoring laboratory was delivered to the Ukrainian Hydrometeorological Center. These deliveries were made possible with funds from Japan, the United Kingdom, the United States and the European Union.