Fukushima Daiichi Unit 3 reactor vessel found with 3-meter hole

Tokyo Electric Power Company (TEPCO) has revealed that a large hole, measuring approximately 3 meters in diameter, exists at the bottom of the Unit 3 reactor pressure vessel at the Fukushima Daiichi Nuclear Power Plant. The discovery was made through 3D reconstruction and analysis of footage captured by ultra-small drones sent into the vessel.

The bottom of the steel pressure vessel, which has an internal diameter of 5.5 meters and a thickness of 14 centimeters, reportedly contains nuclear debris likely resulting from the core meltdown. TEPCO plans to begin large-scale removal of nuclear debris from the Unit 3 reactor as early as fiscal year 2037.

Regarding ongoing operations, TEPCO reports that cooling efforts for reactors 1 through 3 remain stable. Water treatment activities are proceeding, including the drainage of sub-drain water and the management of ALPS treated water. Monitoring of seawater, marine life, and groundwater has shown no significant fluctuations, and the facility continues to maintain a cold shutdown state for several units.