Tokyo Electric Power Co (TEPCO) on Saturday completed the removal of the last four fuel rods from a cooling pool high up in the badly damaged No. 4 reactor building at the wrecked Fukushima Daiichi nuclear power plant.
The operation began last year on Nov 21 and was completed one year ahead of schedule, TEPCO officials said. In total, 1,535 fuel rods were removed from the pool, of which 204 were unused. The rods were transferred to a safer storage pool.
The completion of the operation is considered a major step in the plant's decommissioning process.
However, TEPCO officials said the same process at reactors No. 1-3 will be much more difficult. Radiation levels are higher because of core meltdowns.
Carefully plucking the damaged fuel assemblies from the reactor building is being seen as a test of TEPCO's ability to move ahead with decommissioning the whole facility - a task likely to take decades.
The removal has to be conducted under water. If the rods are exposed to air or if they break, huge amounts of radioactive gases could be released into the atmosphere. Each assembly weighs around 300 kg and is 4.5 meters long.
TEPCO has been slowly pulling the assemblies out of the submerged racks by crane, before transferring them to a heavy steel cask, designed to shield workers from radiation during the operation.© Japan Today/Thomson Reuters