The International Atomic Energy Agency concluded a mission to 19 electrical substations essential to Ukraine's nuclear safety, Director General Rafael Mariano Grossi said on October 30. The mission ran from October 10 to 24 and examined damage, restoration work and the resilience of off-site electricity supplies to Ukraine's nuclear power plants. It was the agency's ninth such mission since September 2024.

On October 27 the IAEA was informed of an attack on the Slavutych substation that reportedly resulted in the loss of all its 330 kV lines. The substation was among those assessed, although the security situation on the ground prevented the team from visiting it.

Zaporizhzhya relies on a single 330 kV line

At the Zaporizhzhya nuclear power plant, one 330 kV line, Ferosplavna-1, maintains essential safety functions. Before the military conflict the plant had ten off-site power lines. The IAEA continues to engage with the Russian Federation and Ukraine on arrangements for a ninth localized ceasefire to enable repairs to the damaged main 750 kV Dniprovska line and the Dniprovska substation.

The Dniprovska line has been unavailable since March. One phase is completely severed, and repairing the section crossing the Dnipro River is expected to be technically complex. Repairs to a backup transformer near the Zaporizhzhya thermal power plant were completed last week under the eighth localized ceasefire. "Every effort must now be made to enable the repair and restoration of a second line," Grossi said.

No diesel deliveries reported since March 2026

A walkdown this week found the daily diesel fuel tanks of all emergency diesel generators fully filled, but reserves at the site remain low after nearly three weeks of generator use following the extended loss of off-site power in August and September. The IAEA has not been informed of any diesel fuel deliveries to the site since March 2026, and military activity in the area has hampered efforts to replenish stocks. Temperatures are expected to fall significantly in the coming months.

Drone attack kills plant worker

The IAEA was informed on October 29 that a ZNPP employee, a welder at the plant's centralized repair workshop, was killed by a drone attack. Teams reported 146 air raid alarms in total, including 115 near Chornobyl, 13 near Khmelnytskyy and 12 near South Ukraine. The agency lost direct contact with its staff at the site for almost 24 hours after a regional internet disruption reported to have been caused by military activity.

Two decontamination cabins were delivered, one to South Ukraine Hospital and one to Varash Hospital, with funding from Japan.