FD-2-used-fuel-pool-survey-June-2020-(Tepco)_1The ROV surveys the used fuel pool of Fukushima Daiichi unit 2 (Image: Tepco)

11 June 2020

There are no obstacles to the removal of assemblies from the used fuel storage pool of unit 2 at the damaged Fukushima Daiichi nuclear power plant, Tokyo Electric Power Company (Tepco) said today after completing an initial survey of the pool. Removal of the assemblies is scheduled to begin fiscal year 2024.

Similar to the reactors at units 1 and 3, unit 2’s reactor suffered a core meltdown after it temporarily lost its cooling functions, but the reactor building – which also houses the fuel storage pool – was spared a hydrogen explosion.

Using a submersible remotely-operated vehicle to investigate the fuel pool, Tepco concluded there was no damage to the fuel assemblies or the storage rack they are held in. It did, however, discover sand-like sediment at the bottom of the pool.

The utility said images captured during the pool’s survey will be used for designing equipment to be used in the removal of the fuel assemblies. It plans to start removing the 587 fuel assemblies from the unit’s used fuel pool between fiscal year 2024 (ending March 2025) and fiscal year 2026 (ending March 2027).

Dose levels on the operating floor of unit 2 are high, thereby making it difficult to access. Tepco has, however, already made progress with the clean-up of equipment, etc. that remains on the operating floor, providing access to the area near the storage pool.

It plans to complete the removal of all fuel assemblies from Fukushima Daiichi units 1-6 during 2031.

https://www.world-nuclear-news.org/Articles/Tepco-completes-survey-of-Fukushima-Daiichi-2-fuel