Here’s the latest of our news bulletins from the ongoing crisis at Japan’s Fukushima Daiichi nuclear power plant.
State of the Fukushima Reactors
Groundwater contamination at the Fukushima Daiichi nuclear power plant has risen by alarming rates over the past five days, and Nuclear Regulation Authority (NRA) Chairman Shunichi Tanaka expressed grave concern this week, saying, “It is strongly suspected that highly concentrated contaminated waste has leaked to the ground and spread to the sea,” adding that it has probably been doing so for more than two years. “I think contamination of the sea is continuing to a greater or lesser extent,” Tanaka said. “It was contaminated at the time of the accident but I think it has been continuing for the last two years. We must find the cause of the contamination and put the highest priority on implementing countermeasures.” However, TEPCO, which has long denied that radioactivity might be seeping into the ocean, refused to acknowledge the seemingly obvious. “It is unclear whether the radioactive water is leaking into the sea,” said one official. Significantly, the utility continues to insist that the ongoing leaks of highly radioactive nuclides have had “no significant impact” on the environment. NRA Commissioner Toyoshi Fuketa seemed doubtful about that claim, saying, “TEPCO says that there has not been meaningful impact on the environment. But we must see for sure what are the possibilities of this leading to oceanic contamination.”
The test samples were gathered from a series of wells that workers dug in order to assess groundwater contamination near the ocean, and the most contaminated by cesium were taken from a well near the water intake of reactor #2, on the seaward side. It sits just 25 meters from the ocean. Recently, TEPCO, which has been suffering from a massive contaminated water storage issue, has been pushing to release groundwater into the sea, initially arguing that it was no more contaminated than water of nearby rivers and streams. The latest findings are likely to make local fishermen’s cooperatives even more reluctant to agree to such a move.
Over the last five days, levels of radioactive cesium have risen by 100 times, and measured 20% more on July 9, compared to the day before. Radioactive tritium and strontium-90 were also high. Current levels as of Wednesday evening JST were 33,000 Bq/liter of cesium (11,000 Bq/liter of cesium-134—180 times the legal limit— and 22,000 Bq/liter of cesium-137—240 times the legal limit); strontium-90 was 900,000 Bq/liter and tritium measured 600,000 Bq/liter. The recent measurements are the highest discovered in groundwater since the nuclear disaster first began to unfold almost two and a half years ago. Wednesday’s measurements showed a significant increase from July 8, when cesium levels measured 27,000 Bq/liter. (The water contained 9,000 Bq/liter of cesium-134 and 18,000 Bq/liter of cesium-137.) Other radioactive substances, including strontium-90, measured 890,000 Bq/liter. And on July 5, cesium levels were only 309 Bq/liter. Levels of cesium, strontium, and tritium have been on the rise since May, although strontium and tritium have fluctuated. Cesium levels were relatively low until this week. TEPCO officials do not know why the numbers are increasing so precipitously.
The well near reactor #2 is not the only one experiencing a rise in contamination levels. Groundwater samples from a well located near reactor #3 contained 1,700 Bq/liter of radioactive materials, approximately 20 times higher than that of samples taken less than a week earlier. TEPCO officials said that they are in the process of testing groundwater from other nearby wells.
Cesium has been linked to human cancer. The half-life of cesium-134 is only 2 years, but for cesium-137, it’s 30 years. Strontium-90 has a half-life of 28.8 years and can accumulate in human bones and cause cancer. Experts have expressed concern about the risks of strontium entering the food chain through contamination of fish and other sea life.
So far, neither TEPCO nor the central government has been able to determine the cause of the leaks, nor are they able to stop the steadily rising contamination in groundwater. The utility is insisting that the current rise in radioactivity is a result of soil that was contaminated immediately following the March 2011 nuclear meltdowns but only recently seeped into the wells via groundwater. Its latest theory is that the groundwater itself is not actually contaminated, but that the sample accidentally got mixed with some very radioactive soil. It was not, however, able to say how that might have happened.Again, officials said that the contamination does not necessarily mean that radioactive substances are leaking into the sea. “We can’t say anything for sure,” said Noriyuki Imaizumi, TEPCO’s spokesperson.
However, the NRA has been openly skeptical about those theories, saying that other wells further from the site of the 2011 leak are also contaminated, and that toxic water may not be the only cause of the problem. And, ocean water gathered at TEPCO’s port showed contamination levels rising in the sea: samples collected near water intakes for reactors #1 to #4 on July 3 measured 2,300 Bq/liter, signaling that radioactive water is pouring into the ocean. It is the highest level ever detected there, and contamination is fast on the rise: on June 21, the water measured 1,100 Bq/liter; on July 1, it contained 2,200 Bq/liter. In discussing the ocean contamination, Tanaka did not sound overly hopeful about solving the problem immediately. “We’ve seen for a fact that levels of radioactivity in the seawater remain high and contamination continues. I don’t think anyone can deny that. We must take action as soon as possible. That said, considering the state of the plant, it’s difficult to find a solution today or tomorrow. That’s probably not very satisfactory to many of you. But that’s the reality we face after an accident like this,” he said, while speaking before a meeting of NRA commissioners.
Experts agree that TEPCO is ignoring the problem. “If there was no leak, we would see far lower levels of radioactive cesium in waters off the plant,” because ocean tides would wash it away, noted Jota Kanda, an oceanographer from Tokyo University of Marine Science and Technology. “This suggests that water might be leaking out from the plant through damaged pipes or drains, or other routes TEPCO doesn’t even know about. We need to find out exactly where these leaks are and plug them,” he added.
TEPCO is trying to inject a waterproof sealing agent into ground near the sea in order to stem the flow of contaminated water, and recently announced plans to install “an impervious wall of frozen soil” to prevent groundwater from flowing seaward. However, no one knows whether or not that will work, and some experts have expressed doubt about its effectiveness.The NRA has ordered the company to finish a submerged containment wall it’s building in the plant’s ocean port earlier than the original completion date of 2015. In addition, NRA officials told TEPCO to remove contaminated water from trenches, in order to prevent further leaks. Meanwhile, the NRA said that it will form its own taskforce to investigate the issue and to prevent further ocean contamination. Regarding the belowground oceanic containment wall, Tanaka said, “We don’t truly know whether or not [the ocean wall] will work. Of course, we’d hope to eliminate all leaks, but in this situation, all we can hope for is to minimize the impact on the environment…When something unexpected happens, we can only take stopgap measures, which shows how unstable Fukushima Daiichi still is. Given the situation, we can only use the best of our wisdom and do what we can.”
Nuclear Regulation Authority and Reactor Restarts
Despite the rapidly deteriorating conditions at the Fukushima plant, and the fact that a majority of Japanese people supports eventual phase-out of nuclear power, the central government, under the direction of Prime Minister Shinzo Abe, continues to push for the restart of the nation’s idled reactors. Analysts say that Shikoku Electric’s reactor #3 at its Ikata plant is the most likely to be among the first restarted. The NRA has said that each safety assessment will take approximately six months, after which local consent needs to be obtained. The nuclear industry is eager to restart reactors as soon as possible. However, Kenzo Oshima, an NRA Commissioner, seems to think that the process may take longer. “Some units are projected to restart one year from now, though I don’t know how many [or which ones],” he said.
Eight of Japan’s nine nuclear power providers posted a combined loss of 1.6 trillion yen ($15.8 billion) during fiscal year 2012, and seem more interested in their bottom line than residents’ safety. “The reactivation of reactors is necessary not to inconvenience our customers with higher electricity rates,” said Toru Yoshizako, of Kyushu Electric. But the governor of Kyoto, Keiji Yamada, takes issue with that viewpoint, as well as the NRA’s effectiveness as an arbiter of safety. “It’s hard to understand why electric power companies have been given a grace period to implement safety measures under the new regulations. Moreover, the regulations don’t provide for sufficient measures to respond to an accident, such as how to ensure the safety of residents around nuclear plants. There remain tasks that must be addressed before restarting idled nuclear reactors,” he said. “The lesson of the Fukushima nuclear crisis is that nuclear plants (which could cause serious damage in case of an accident) cannot be considered simply from the viewpoint of private companies’ management. The government should further clarify its own responsibility for Japan’s nuclear power policy,” Yamada added.
The NRA is slated to begin its safety checks at reactors even though many surrounding cities and towns still do not have adequate evacuation plans in place, and could be forced into complete isolation if another massive earthquake, tsunami, and earthquake were to occur. Considering the number of fault lines sprinkled across Japan, experts say that those are realistic likelihoods. A survey by the Mainichi Daily News reveals that 58 municipalities located within 30 km of a nuclear reactor could be isolated in the case of a nuclear disaster. Although Japan’s Basic Law on Disaster Control Measure requires municipal officials to create evacuation plans, for some areas, that’s simply not feasible. The town of Shakotan in Hokkaido Prefecture, which lies on the coast, is so isolated that its evacuation plans rely on residents escaping via fishing boats and Self Defense Force helicopters. “The transportation capacity of helicopters and boats is limited, and I wonder if we could actually use them when it came down to it,” worried one town official. In Ayabe, located in Kyoto Prefecture, roads are narrow and limited. “Thinking about the geographical considerations and the cost involved, road maintenance is unrealistic. We can only make preparations within our capacity,” lamented an official. Some analysts say that placing the responsibility for saving the populace when a nuclear disaster occurs on local governments, rather than the central government, is in itself unrealistic.
Masao Yoshida, who defied orders from TEPCO’s headquarters and continued to work to cool the Fukushima Daiichi reactors as they melted down, has died of esophageal cancer. He was 58. TEPCO said that his death was not related to radiation exposure. Following a hydrogen explosion at reactor #1 on March 12, TEPCO ordered Yoshida to stop spraying ocean water on the reactor, because then-Prime Minister Naoto Kan was concerned about triggering a fission chain reaction. Yoshida ignored the orders, preventing the situation from worsening and triggering a major catastrophe that could have required evacuation of greater Tokyo’s 35 million residents. Kan later praised Yoshida for his actions during the crisis, and mourned his death this week. “We are largely indebted to Mr. Yoshida for preventing the accident from further expanding.” Goshi Hosono, who served as Nuclear Crisis Minister in the months following the meltdowns, agreed. “Without Mr. Yoshida’s leadership and fighting spirit, we would not have been able to overcome that situation,” he said. Yoshida was well respected by his own workers, and was later frank about his fears as the meltdowns were occurring. “There were several instances when I thought we were all going to die here. I feared the plant was getting out of control, and we would be finished,” he recalled. However, some have criticized him for ignoring his own calculations, drawn up two years earlier, which showed that a tsunami far larger than those previously predicted could affect the plant. “It is nothing but a preliminary calculation based on the most severe hypothesis,” he said, dismissing his own work. Unfortunately, it turned out to be more accurate than he imagined.