Exhausted engineers attached a power cable to the outside of Japan’s tsunami-crippled nuclear plant on Saturday. The operation raised hopes that it may be possible to restart the pumping of water into the plant’s stricken reactors and cool down its overheated fuel rods before there are more fires and explosions.
“We have connected the external transmission line with the receiving point of the plant and confirmed that electricity can be supplied,” a spokesman for the plant’s operator, Tokyo Electric Power Co, said in a statement.
However, officials said further cabling would have to be completed before they made an attempt to restart the water pumps at the Fukushima Dai-ichi nuclear power plant.
It was also reported that health workers had detected radiation levels above safety limits in milk and spinach from farms in Fukushima and in neighboring Ibaraki Prefecture, although it was claimed they represented no risk to human health. Officials have asked people living near the plant to follow basic safety advice when going outside — drive, don’t walk; wear a mask; wear long sleeves; don’t go out in the rain.
Radiation levels in Tokyo were also said to be within safe limits. Nevertheless, the city has seen an exodus of tourists, expatriates and many Japanese, who fear a blast of radioactive material from Fukushima.
At the nuclear plant on Saturday, firefighters continued to spray water to cool the dangerously overheated fuel rods in order to keep cores in its reactors from overheating and melting.
The UN’s atomic agency said conditions at the plant remained grave, but not deteriorating badly, following Japan’s decision on Friday to raise the severity rating of the nuclear crisis from level four to level five on the seven-level international scale. It put the Fukushima fires on a par with the Three Mile Island accident in Pennsylvania in the US in 1979.
The explosion at Chernobyl in 1986 — which sent a plume of radioactive material into the skies 25 years ago — is the only incident to have reached level seven.
Fires and explosions occurred at four of the six reactors at Fukushima last week after the magnitude 9.0 earthquake and the ensuing tsunami that hit Japan on March 11. The earthquake triggered an automatic shutdown of the three reactors that were in operation. The tsunami then damaged diesel generators that were providing back-up power for the pumps driving coolant through the reactors.
As a result, heat could no longer be pumped away and temperatures inside the reactors’ cores began to rise, eventually setting off a series of chemical fires.
“Hollow rods made of zirconium hold each reactor’s uranium fuel pellets in place,” said Andrew Sherry, director of the Dalton Nuclear Institute in Manchester, England. “When temperatures rise too much, that zirconium starts to react with the reactor’s water. This chemical reaction raises temperatures even further. Hydrogen is also produced. When this hydrogen exploded, it destroyed the buildings that act as each reactor’s outer protective shell.”
The explosions also damaged two storage tanks in which fuel rods — still hot because of the radioactive material inside them — were being stored in water. Water levels dropped, exposing fuel rods and triggering further chemical reactions between zirconium fuel cladding and the steam that had begun to build up. These set off fires in storage tanks at reactors three and four.
As a result, plant workers, emergency services personnel and scientists have been battling for more than a week to restore the pumping of water to the Fukushima Dai-ichi nuclear power plant and to prevent a meltdown at one of the reactors. A team of about 300 workers — wearing masks, goggles and protective suits sealed with duct tape and known as the “Fukushima 50,” because they work in shifts of 50-strong groups — have captured the attention of the Japanese, who have taken heart from the toil inside the wrecked plant.
“My eyes well with tears at the thought of the work they are doing,” said Kazuya Aoki, a safety official at Japan’s Nuclear and Industrial Safety Agency.
Little is known about this band of heroes, except for the few whose relatives have spoken to the Japanese media. One woman said that her father, who had worked for an electricity company for 40 years and who was scheduled to retire in September, had volunteered.
“I feel it’s my mission to help,” he told his daughter.
On Wednesday, the government raised the cumulative legal limit of radiation that the Fukushima workers could be exposed to from 100 millisieverts to 250 millisieverts. That is more than 12 times the annual legal limit for workers dealing with radiation under British law. Each team works as fast as possible for the briefest of periods. The pilots of the helicopters used to “water-bomb” the plant have been restricted to missions lasting fewer than 40 minutes.
Nevertheless, the workers have not only managed to link a power cable to one of the plant’s reactors, No. 2, but they have also connected diesel generators to the No. 5 and No. 6 reactors, which have so far not suffered serious damage.
“If they are successful in getting the cooling infrastructure up and running, that will be a significant step forward in establishing stability,” said Eric Moore, a nuclear power expert at the US-based FocalPoint Consulting Group.
However, the government has conceded that it was too slow in dealing with the crisis at Fukushima Dai-ichi.
“In hindsight, we could have moved a little quicker in assessing the situation and coordinating all that information, and provided it faster,” Japanese Chief Cabinet Secretary Yukio Edano said.
The fires at Fukushima Dai-ichi have triggered serious criticism of the plant’s design. The decision to place storage tanks close to reactors has been pinpointed as a key design error. When those reactors caught fire, they quickly triggered reactions in the storage tanks, which themselves caught fire, and so the fires spread.
The failure to build defenses that could withstand the huge tsunami that struck Japan has also been attacked.
“The geological evidence in Japan indicates a history of giant tsunamis over the past several thousand years,” said Rolf Aalto, an Exeter University expert on tsunamis. “Unfortunately, an engineering and political decision was made to design protection and plan cities around a hypothesized 5m tsunami — about the size of those experienced in Japan over the last century. However, it was not a surprise to geologists that a tsunami two to three times larger appeared. Both the earthquake and tsunami were exceptional, but were both well within the realm of what can occur within that tectonic setting.”
However, Sherry defended the ageing plant — whose six reactors came on line between 1970 and 1979.
“These reactors were designed in the 1960s and we have learned a lot since then. Modern plants are much safer. Think of cars in the 1960s — they didn’t have crumple zones, airbags or seat belts — features we all take for granted today. It is the same with nuclear reactor design,” Sherry said.
The Fukushima Dai-ichi reactors, known as boiling water reactors, have active safety features — you have to do something to prevent dangerous heating, such as ensuring that the pumps are activated.
“By contrast, new reactors are designed to include ‘passive’ safety systems that are designed to shut down and cool fuel without the need for power being available at the plant,” said Barry Marsden, professor of Nuclear Graphite Technology at Manchester University.
Modern reactors also have double or triple back-up safety systems. It remains to be seen if such reassurances will have an impact.
The sight of explosions erupting from the reactors last week have done nothing for the prospects of the world’s nuclear industry. It had been gearing up for a restoration of its fortunes, with governments across the planet turning to the power of the atom as a future energy source — one that does not pose major climate change risks. It now looks like a tarnished option, or at least that is how it will be portrayed by those who oppose an expansion of nuclear power plant construction.
“European leaders must take note of the growing nuclear crisis in Japan and act now,” said Patricia Lorenz, nuclear campaigner for Friends of the Earth Europe. “Europe needs a phase-out plan for nuclear, and [it] must open the way for safe solutions to climate change and energy security.”
Last week, the German government suspended its approval process for new nuclear power construction projects. More significantly, China — the world’s leader in nuclear expansion, with 28 plants under construction — followed suit.
Whether these suspensions will last long is a different matter. Much depends on the success of the “Fukushima 50” and their bid to complete a power link between the stricken plant and the outside world. Failure would certainly do little for the reputation of nuclear power.
Late last month, Beijing introduced changes to school curricula in the Inner Mongolia Autonomous Region, requiring certain subjects to be taught in Mandarin rather than Mongolian. What is Chinese President Xi Jinping (習近平) seeking to gain from sending this message of pernicious intent? It is possible that he is attempting cultural genocide in Inner Mongolia, but does Xi also have the same plan for the democratic, independent nation of Mongolia? The controversy emerged with the announcement by the Inner Mongolia Education Bureau on Aug. 26 that first-grade elementary-school and junior-high students would in certain subjects start learning with Chinese-language textbooks, as
There are worrying signs that China is on the brink of a major food shortage, which might trigger a strategic contest over food security and push Chinese President Xi Jinping (習近平), already under intense pressure, toward drastic measures, potentially spelling trouble for Taiwan and the rest of the world. China has encountered a perfect storm of disasters this year. On top of disruption due to the COVID-19 pandemic, torrential rains have caused catastrophic flooding in the Yangtze River basin, China’s largest agricultural region. Floodwaters are estimated to have already destroyed the crops on 6 million hectares of farmland. The situation has been
The restructuring of supply chains, particularly in the semiconductor industry, was an essential part of discussions last week between Taiwan and a US delegation led by US Undersecretary of State for Economic Growth, Energy and the Environment Keith Krach. It took precedent over the highly anticipated subject of bilateral trade partnerships, and Taiwan Semiconductor Manufacturing Co (TSMC) founder Morris Chang’s (張忠謀) appearance on Friday at a dinner hosted by President Tsai Ing-wen (蔡英文) for Krach was a subtle indicator of this. Chang was in photographs posted by Tsai on Facebook after the dinner, but no details about their discussions were disclosed. With
On Sept. 8, at the high-profile Ketagalan security forum, President Tsai Ing-wen (蔡英文) urged countries to deal with the China challenge. She said: “It is time for like-minded countries, and democratic friends in the Indo-Pacific region and beyond, to discuss a framework to generate sustained and concerted efforts to maintain a strategic order that deters unilateral aggressive actions.” The “Taiwan model” to deal with the COVID-19 pandemic provides an alternative to China’s authoritarian way of handling it. Taiwan’s response to the health crisis has made it evident that countries across the world have much to learn from Taiwan’s best practices and if