Drone Explores Fukushima Reactor For Melted Fuel Debris

• Small drones explore damaged reactors at Fukushima Daiichi plant.

• Previous robots failed to reach molten fuel debris.

• TEPCO releases treated radioactive wastewater into the sea, facing opposition.

This aerial view shows the wrecked Fukushima Daiichi nuclear power plant in Okuma town, northeastern Japan, on Aug. 24, 2023. A drone small enough to fit in one's hand flew inside one of the da

AP

A small drone successfully flew inside one of the damaged reactors at the Fukushima Daiichi nuclear power plant on Wednesday. The drone, compact enough to fit in one's hand, aims to examine areas where previous robots failed to reach, specifically to investigate the molten fuel debris.

Simultaneously, Tokyo Electric Power Company Holdings initiated the release of the fourth batch of treated radioactive wastewater from the plant into the sea. Despite assurances from the government and TEPCO regarding the safety of the water, the discharge has faced opposition from fishing groups and a ban on Japanese seafood by China.

The Fukushima Daiichi plant suffered a meltdown in three reactors following a magnitude 9.0 earthquake and tsunami in March 2011. The decommissioning process, which involves removing the highly radioactive melted nuclear fuel, has been plagued by delays and technical challenges.

To gather crucial data for this process, a fleet of drones was deployed to enter the primary containment vessel of the most severely affected No. 1 reactor. Previous attempts using crawling robots and underwater vehicles were impeded by debris and high radiation levels.

The drones, weighing only 185 grams each, are equipped with high-definition cameras to capture live video and images inside the reactor. Due to battery limitations, each drone is restricted to a 5-minute flight duration.

TEPCO plans to utilize the data collected by the drones to develop advanced probe technology and strategies for removing the melted fuel. The investigation aims to shed light on the events leading to the 2011 meltdown.

The drones will first inspect the exterior area around the main structural support in the reactor vessel before potentially exploring previously inaccessible regions. The ultimate goal is to understand how overheated fuel dripped to the core's bottom during the disaster.

With approximately 880 tons of melted nuclear fuel remaining in the damaged reactors, the cleanup process at Fukushima Daiichi is expected to be lengthy and challenging. TEPCO's current target is to extract a small amount of debris from the No. 2 reactor by the end of March using a robotic arm, although recent delays underscore the complexity of the operation.