First fuel removed at Japanese nuclear site hit by 2011 tsunami
● Work will take two years, with operations at other plants to follow
The operator of the Fukushima nuclear plant has begun removing fuel from a cooling pool at one of three reactors that melted down in the 2011 Japanese tsunami disaster.
Reactor buildings at the Fukushima Daiichi power plant were damaged by hydrogen explosions caused by the earthquake and tsunami. Three reactors melted down.
Tokyo Electric Power Co (Tepco) said workers have now started removing the first of 566 used and unused fuel units stored in the pool at Unit 3.
The fuel units in the pool located high up in reactor buildings are intact despite the disaster, but the pools are not enclosed, so removing the units to safer ground is crucial to avoid disaster in case of another major quake.
Tepco says the removal at Unit 3 would take two years, followed by the two other reactors where about 1,000 fuel units remain in the storage pools.
Removing the fuel units from the cooling pools comes ahead of the real challenge of removing melted fuel from inside the reactors, but details of how that might be done are still largely unknown.
The process of removing the fuel in the cooling pools was delayed more than four years by mishaps, high radiation and radioactive debris from an explosion that occurred at the time of the reactor meltdown, underscoring the difficulties that remain.
Workers are remotely operating a crane built underneath a roof cover to raise the fuel from a storage rack in the pool and place it into a protective cask. The whole process occurs underwater to prevent radiation leaks.
Each cask will be filled with seven fuel units, then lifted from the pool and lowered to a truck that will transport the cask to a safer cooling pool elsewhere at the plant.
The work is carried out remotely from a control room about 500 metres away because of still-high radiation levels inside the reactor building that houses the pool.
About an hour after the work began, the first fuel unit was safely stored inside the cask, Tepco said.
“I believe everything is going well so far,” plant chief Tomohiko Isogai told Japan’s NHK television from Fukushima. “We will watch the progress at the site as we put safety first. Our goal is not to rush the
process but to carefully proceed with the decommissioning work.”
In 2014, Tepco safely removed all 1,535 fuel units from the storage pool at a fourth reactor that was idle and had no fuel inside its core when the 11 March 2011, earthquake and tsunami occurred.
Robotic probes have photographed and detected traces of damaged nuclear fuel in the three reactors that had meltdowns, but the exact location and other details of the melted fuel are largely unknown.
Removing fuel from the cooling pools will help free up space for the subsequent removal of the melted fuel, though details of how to gain access to it are yet to be decided.
Nearly 18,500 people were killed or went missing after the 2011 earthquake triggered a massive tsunami.
The disaster at the nuclear power plant, about 39 miles south-east of the city of Fukushima, forced more than 470,000 people to be evacuated.
Though no-one died as a direct result of the nuclear meltdown, Tepco has paid out compensation to some of those affected. In 2017, three former Tepco executives went on trial charged with professional negligence.
The latest stage of the cleanup comes weeks after an evacuation order for one of two towns near the plant was lifted, allowing residents back for the first time since the disaster. About 50 people were allowed to return to areas of Okuma, west of the Daiichi plant, after radiation levels were deemed safe.