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Financial FT MAGAZINE Close How Fukushima failed By Jonathan Soble and Mure Dickie Published: May 6 2011 17:52 | Last updated: May 6 2011 17:52 Inside the nuclear exclusion zone in April. Visible on the horizon: the Fukushima Daini plant, about 15km from the Fukushima Daiichi plant where the explosions happened Ryota Takakura was packing low-level radioactive waste into drums when the ground started shaking. It was 2.46pm on March 11, and the biggest earthquake ever recorded in Japan was rippling along the country’s north- east coast. It buckled roads, toppled electricity pylons and rattled Fukushima Daiichi Nuclear Power Plant, the sprawling six-reactor facility where Takakura worked doing basic maintenance. As the ground heaved, he and a group of colleagues clustered around a pillar in the plant’s waste disposal building, clutching each other to stay on their feet. Then the lights went out, leaving them in pitch darkness amid the groans of the building. When Takakura took the job at Daiichi three months before, he worried it might be dangerous. Such doubts were soon “brainwashed” out of him by plant trainers, he jokes. Now they roared back. “I thought that an earthquake like this,” he says, “might cause an explosion.” His instincts were right: the tremor had triggered what would become the world’s worst nuclear accident in 25 years. Yet to the plant’s safety officials, the situation looked manageable. The three reactors in operation when the quake hit had shut down as designed: neutron-absorbing control rods sprung up automatically into their cores, halting nuclear fission. While the local power grid had been knocked out, the plant had its own generators to keep vital systems working. What they did not yet realise was that the offshore earthquake had unleashed a greater menace. Over the grey horizon, a vast pulse of water was racing toward the row of reactors, which sat, suddenly vulnerable, on a shelf of land between low hills and the sea. .................................................. The wave Japan has never been an ideal place to build a nuclear power plant. Perched on the seismic “Ring of Fire” that runs around the Pacific Ocean, even its most stable areas are never far from an earthquake fault, and most of its coasts have been battered at some point or other by tsunamis. Ironically, geology has also driven Japan’s embrace of atomic power. With no significant reserves of fossil fuel, it must import nearly all its energy – a matter of national insecurity since before the second world war. The oil shocks of the early 1970s, when crude prices soared, reinforced a determination to diversify supply. When the quake hit, 54 commercial reactors across Japan accounted for nearly 30 per cent of the country’s electricity generation. Everyone at Fukushima Daiichi felt the terrible force of the earthquake, but few witnessed the arrival of the massive tsunami about 50 minutes later. Lower- tier workers like Takakura had fled or were stuck in a traffic jam at the plant’s main gate, more than a kilometre inland. Managers and technicians were gathered in a windowless crisis centre – where they would end up surrounded by water they could not see. The waves left plenty of evidence of their passing, however. They swept over the plant’s 5.5m-high concrete sea wall, breaking it in places, then surged across a narrow seafront road and crashed into buildings containing turbines and, behind them, the reactors. External pipes were ripped from walls, The No 3 reactor ablaze at Fukushima Daiichi workers’ cars were washed away and a tanker truck knocked on its side. The tsunami reached more than 14m above sea level – roughly the height of a five-storey building – and the four lowest-lying reactor buildings were surrounded by swirling seawater 4-5m deep. One area in particular suffered critical damage: a row of diesel generators located between the turbine buildings and the sea. These were the plant’s back-up power supply, but now they were choked with seawater. Only one still worked, and it was not enough: lights and instruments flicked off in the plant’s control rooms, and core cooling systems stopped dead. Even after a reactor’s nuclear chain reaction is halted, its uranium fuel gives off enough heat to keep the water inside its central chamber boiling. This creates steam, and steam creates pressure inside the vessel. If left uncooled, the vessel will eventually rupture – releasing radiation and uranium outside the chamber. A little more bad luck, and the spilled fuel can achieve “re-criticality” – a new, and uncontrolled, fit of nuclear fission. With the back-up generators disabled, engineers were down to their final fail-safes for cooling the reactors: a heat-exchanging condenser and pressurised water-injection tanks. Both would only work for a few hours. .................................................. The response A few minutes after the quake, Goshi Hosono, deputy secretary general of the Democratic party and a senior aide to Japan’s prime minister, arrived at his boss’s elegant official residence in Tokyo. The challenge of responding to the crisis fell to an inexperienced government that just hours before had appeared to be teetering. Public support for Prime Minister Naoto Kan was low, sections of his ruling Democratic party were in revolt, and a new scandal had broken that morning over alleged political donations from a foreign resident – a relatively minor violation, but one that had forced out the foreign minister the week before. After winning power for the first time in September 2009, the Democrats’ grip on it looked shaky. The need to oversee a vast relief operation for Japan’s tsunami-devastated coast would have been taxing enough, even without the atomic crisis. “From about 4pm we were having to fight on two fronts,” says Hosono, a 39-year-old Democratic rising star who was quickly named the prime minister’s nuclear point man. The task was made even more difficult by the Japanese authorities’ long- standing assumption that total power loss at an atomic plant was virtually impossible. “The situation was not one that could be resolved by following a manual,” Hosono says. .................................................. The warnings Fukushima Daiichi’s fate was foreseen by one person, however, now glued to a television screen in his office just down the street from the prime minister’s residence. Hidekatsu Yoshii, a member of parliament from the Japanese Communist party, had for years been warning that Japan’s nuclear plants were more vulnerable to natural disasters than officials and regulators assumed. He reckoned Daiichi’s final back-up cooling systems could last seven or eight hours. “From 5 or 6pm I was watching the clock.” Yoshii was born during the war and studied nuclear engineering at Kyoto University – inspired by the idea that the atomic power that destroyed Hiroshima and Nagasaki could be put to peaceful use. But the 1979 accident at Three Mile Island in the US, the 1986 Chernobyl disaster and a series of smaller incidents in Japan convinced him that the industry’s current level of technology was unsafe. Five years ago, he had outlined in parliamentary debate how a combination of earthquake and tsunami could knock out a Goshi Hosono, 39, deputy Japanese atomic station’s cooling systems. He secretary general, Democratic was concerned less about flooding than the risk Party: ‘The situation was not one that water intakes might be left exposed when the that could be resolved by following a sea drew back before a tsunami’s arrival. Still, his manual’ insistence that the government needed to prepare for catastrophic cooling failure was prescient. Reactor overheating could cause steam or hydrogen explosions, he warned. “It is essential to have proper countermeasures in place for something that could be close to a Chernobyl.” Hidekatsu Yoshii, 68, lower house These warnings fell on deaf ears, as did similar representative: ‘Countermeasures are vital for something that could be ones from academic researchers and activists. close to a Chernobyl’ Tokyo Electric Power Company (Tepco), operator of Fukushima Daiichi, said its plants were designed to withstand the “largest conceivable earthquake” – even after the official view of what was conceivable was undermined by new research. In recent years, for instance, geologists sifting soils along the north-eastern coast had found evidence that a huge tsunami had hit the area before, depositing silt 3km or more inland. The findings drew renewed attention to a historical account of a disastrous inundation in the year 869. “Plains and highways were turned into an expanse of sea,” it reads, chiming eerily with experiences of coastal residents on March 11. “Nothing was left of property or the produce of the fields.” Nuclear sceptics say there were many reasons officials refused to listen to their warnings – from the high cost of upgrading atomic plants to a defensive mindset that lumped constructive critics with outright abolitionists. Some officials at the economy and industry ministry – which led Japan’s embrace of nuclear power – now acknowledge that blanket promises that plants were invulnerable made it difficult to improve their defences, because changing anything meant acknowledging some level of danger. “Whatever happened, the plants were always declared safe enough to operate,” says one bureaucrat who now regrets the ministry’s simplistic approach. “It was all lies.” .................................................. The deserted streets of Minamisoma, Fukushima, inland from the power plant, in the exclusion zone Radiation leak As the hours ticked by at the plant, attempts to get electricity to the reactors were going nowhere. Tepco scrambled to find a generator truck, but it took hours to arrive – and was then found to be useless because its plugs were incompatible with those of the plant.