|November 06, 2014|
TEPCO Finishes Removing 400 Tonnes of Spent Fuel Rod From Fukushima Reactor 4
|After 12 long months, Tokyo Electric Power Company or TEPCO, has finally completed the removal of all spent fuel rod assemblies from the storage pool at the damaged Fukushima Daiichi unit 4. The spent uranium fuel that was removed accounted for a total of 400 tonnes.|
TEPCO said last Wednesday that there still remains some 180 unused fuel assemblies in the pool. But these are less-risky, it said. The materials will be removed by year end.
The company said it had placed in a storage pool at ground level of the plant all the 1,331 recovered spent fuel assemblies. Kyodo News reported that these were initially located on the top floor of the No. 4 building, which was rocked by a hydrogen explosion early in the crisis. Located 30 metres above ground, the pool had been left uncovered since the explosion three years ago. The spent fuel rods are now going to be checked for signs of damage.
The Fukushima Daiichi nuclear power plant has six reactors. Reactors No. 1-3 went into partial meltdown resulting from the tsunami. The incident damaged their cooling systems. Reactor No. 4 suffered a hydrogen explosion.
Reactors No. 5 and 6, meantime, were less badly affected. Their fuel remains stored and all are in stable condition, according to RIA Novosti. The removal of the used fuel marks, TEPCO said, marked "a solid step toward the decommissioning of the plant." The entire decommissioning process will take up 40 years.
Fuel from Reactor No. 1 will be removed starting 2019, two years later than originally planned. TEPCO has recently removed the canopy over the building to allow debris removal. Removal of debris at the Reactor No. 3 is ongoing through remote-controlled robots, while the interior of the building of Reactor No. 2 is currently being surveyed.
Unlike at Reactor No. 4, Reactors No. 1-3 were highly operational when the tsunami happened and disaster struck. These reactors have higher levels of radioactive contamination because of the meltdowns. The three reactor buildings are holding a total of 1,400 fuel assemblies in storage pools.
Once all the spent fuel are already removed, TEPCO can now focus on extracting the reactor cores that reacted during the disaster. It is deemed the most difficult task and one that has never been done before, Reuters said. The operation is scheduled to start in 2025.