Masao Yoshida – whose actions as manager of the Fukushima Daiichi power plant during its triple meltdown averted an even greater disaster – has died.
Yoshida, 58, took early retirement from the plant’s operator, Tepco, in late 2011 after being diagnosed with oesophageal cancer. He died in a Tokyo hospital on Tuesday, reports said.
Tepco and Yoshida, a heavy smoker, said the cancer was not related to the nuclear accident caused by the March 2011 tsunami that hit Japan.
Although Tepco has been widely criticised for its handling of the accident, Yoshida’s courage and refusal to follow orders from the firm’s headquarters after the plant was struck by a 42-foot tsunami on the afternoon on 11 March 2011 have been credited with preventing a catastrophic release of radiation that could have forced the evacuation of Tokyo.
The 58-year-old stayed on at the plant to direct the perilous operation to cool its crippled reactors amid frequent aftershocks and hydrogen explosions inside reactor buildings.
He will be remembered most of all for defying an order from senior Tepco officials in Tokyo to stop pumping seawater into one of the damaged reactors in a frantic effort to keep it cool. Tepco officials were concerned that pumping seawater into the reactors would render them commercially useless.
His death will deprive experts of an important source of information for future investigations into the accident. More than two years after the triple meltdown radiation levels in key areas of Fukushima Daiichi are still far too high for on-site inspections.
Workers at the plant are also struggling to treat huge amounts of contaminated water used to cool melted fuel deep inside three of the plant’s six reactors.
This week Tepco said it had detected a dramatic spike in radioactive caesium levels in groundwater in an area of the plant close to the sea.
The discovery is another blow to efforts to clean up the site; the operation to remove melted fuel from the reactors and decommission the facility is expected to take about 40 years.
Tepco officials said they had found levels of caesium-134, which has a half life of about two years, at 9,000 becquerels per litre inside a well on Tuesday – about 90 times higher than levels three days earlier and 150 times higher than Japan’s safety standard.
The company said it had yet to determine the cause of the radiation spike.
The tsunami killed more than 18,000 people along Japan’s north-east coast and forced the evacuation of 150,000 residents from villages and towns close to the Fukushima Daiichi plant.
Yoshida, who had been manager of the plant for just nine months when the tsunami knocked out its regular and emergency power supplies, was reprimanded but later hailed as a hero as it became clear that his actions had saved the plant from a nuclear fission chain reaction – a potentially far more devastating scenario than a fuel meltdown.
“I bow deeply out of respect for his leadership and decisiveness,” the prime minister of the time, Naoto Kan, wrote on Twitter after Yoshida’s death was reported. “I wish I had had the chance to talk to him at length about the nuclear disaster once again.”
Video footage from the earthquake-proof bunker from which Yoshida directed the mission to save the plant shows him occasionally apologising to colleagues for sending them out to connect water supplies to dangerously overheating reactors.
He is later persuaded to abandon a “suicide” mission, which he offered to lead, to cool another reactor.
Despite his largely calm demeanour at the time, Yoshida would later admit that he feared he and his colleagues would perish inside the plant. “During the first week of the accident I thought several times that we were all going to die,” he told journalists shortly before he retired.
Yoshida insisted he had never once considered a total withdrawal from the plant, a prospect that brought him into conflict Kan, who had warned Tepco bosses that a total evacuation of the plant would spell the end of the utility.
The company’s president, Naomi Hirose, paid tribute to Yoshida’s contribution and his ability to encourage the other engineers and emergency workers – nicknamed the Fukushima 50 – who braved high levels of radiation in the early days of the crisis.
“We deeply appreciate his contribution and the way he handled the accident,” Hirose said in a statement. “He literally put his life at risk in dealing with the accident.
“We keep his wishes in our hearts and will do the utmost to rebuild Fukushima, which he tried to save at all costs.”
TAP – still radiation levels are rising and thyroid cancers are rising. The crisis is far form over, even though it is hardly ever mentioned in the main media.