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
TEPCO is once again under fire this week, after two separate leaks were reported in underground tanks designed to hold radioactive water used to cool reactors. On April 5, TEPCO reported that 120 tons (almost 29,000 gallons or nearly 110,000 liters) of highly radioactive water had leaked from tank #2, which is approximately the size of several football fields and holds 13,000 tons of water. There are seven tanks at the facility, each consisting of a hole dug into the ground and then lined with two layers of polyethylene, and an outer layer of clay. Each layer is separated by felt.
Officials said that water leaking from tank #2 contained 6,000 Bq/cm 3 of radiation, based on water discovered between two of the polyethylene sheets, for a total of 710 billion becquerels. However, experts suspect that the water may actually be far more radioactive, because levels of water within the tank itself measured 290,000 becquerels. They surmise that groundwater may now be seeping in, diluting the water found beneath the plastic sheets. If so, the overall amount of water leaked may actually be 50 times more radioactive than TEPCO has admitted, for a whopping total of 35 trillion becquerels. Hideo Yamazaki, a professor at Kinki University, said, “I cannot understand why TEPCO used a lower figure as the basis for this calculation. Such calculations should be conducted strictly from the viewpoint of ensuring safety.” Professor Masanori Aritomi, from the Tokyo Institute of Technology, agreed: “There’s a common understanding that such calculations should be based on the initial concentration of radioactive substances. I’m afraid TEPCO is underestimating the seriousness of this incident.”
In addition, the utility determined that 120 tons of water leaked, based on water levels within the tank. If groundwater has entered the tanks, it means that the original water levels might be even lower than thought, and more highly radioactive water may have escaped.
Officials said that the leak was first discovered on April 3, but they waited two days to report it to the Nuclear Regulation Authority (NRA), saying, “We believed a detailed investigation was needed [before submitting the report].” Based on falling water levels in the tank, officials now believe that the leak began as early as March 20, but the discrepancy wasn’t investigated at the time and was simply attributed to margin of error. At the same time, radioactivity concentrations in the water changed, but again, the utility failed to notice. Earlier this month, TEPCO was widely criticized for failing to report power loss to spent fuel pools, which could have ultimately resulted in a major nuclear disaster, to the NRA, local government officials, and the media for several hours.
On April 7, TEPCO reported a second, smaller leak in tank #3, which holds 11,000 tons. So far, water levels in that tank have not dropped significantly. Officials suspect that both leaks are a result of failures in the polyethylene sheets. A TEPCO spokesman explained, “There is the possibility that joints in the water-shielding sheets have been damaged. The sheets turned out not to have the ability for which they were designed.” Officials believe that the issue may be a result of inadequate seals on the sheets, resulting in their being compromised when the weight of the water caused stress on seams. However, that theory cannot be tested until water is drained from the pools and the structure is examined. Experts are now raising concerns that all seven underground tanks, which are all constructed similarly, may be at risk of leaking. Some have charged TEPCO with trying to save money by cutting corners and digging what are essentially storage pits, rather than building more expensive steel-reinforced tanks.
TEPCO has been grappling with issues regarding contaminated water since the disaster first began in March 2011. Each day, the utility pumps 370 tons of water into the damaged reactors in order to keep them cool. In addition, an estimated 400 tons of groundwater seep into the reactor basements, through cracks in the buildings. That water also becomes contaminated. The plant currently has capacity to store 325,000 tons of water in hundreds of holding tanks on the premises, but has already used 80% of that space. Overall, the Fukushima Daiichi facility is currently holding 370,000 tons of radioactive water, including water in the reactors themselves. More tanks are being built. But, because the decommissioning process is expected to take 40 years or more, company officials are scrambling to come up with a better plan. So far, they have not been able to do so.
Meanwhile, the utility admitted that power to critical cooling systems at reactor #3’s spent fuel pool was lost for a second time in less than a month, after workers installing a net designed to keep rodents away from a switchbox accidentally touched cables, causing a short in the system. Power was out for several hours, and although temperatures at the pool did not go up significantly, analysts say that the incident highlights poor safety conditions at the plant. The power loss could have been avoided had TEPCO purposely shut power down before beginning the job, but workers neglected to do so. The company admitted that it made a poor choice, saying, “We are sorry for causing the trouble. We will be more careful so that we will not make [more] mistakes.” Workers were installing nets in response to a larger power loss last month, in which cooling systems connected to several spent fuel pools at the plant were halted for over 29 hours, after a rat ran across cables on a switchbox that had been operating outdoors on a truck for more than two years. The spent fuel pool at reactor #3 contains 566 fuel assemblies (of these, 514 contain spent fuel.)
The leaks and power losses follow several other problems and missteps over the past few weeks, in which a water purification system stopped when a worker accidentally hit the wrong switch, and alarms connected to radiation monitors near the plant’s main gate went off, signaling high radiation levels. Officials said that incident was presumably caused by an equipment malfunction.
In fact, experts say that many of the problems that the plant is currently facing are the result of TEPCO’s failure to replace and upgrade temporary and makeshift equipment, more than two years after the nuclear disaster first began to unfold. This week, 10 members of the Diet’s investigative panel into the causes of the Fukushima disaster, led by Kiyoshi Kurokawa, testified before a special Lower House committee. Their report, which was released last July, said that the Fukushima nuclear crisis was “a man-made disaster.” On Monday, Kurokawa observed, “Obviously, the crisis is not yet under control,” referring to the many recent technical and human failures. He added, “Moreover, a response to victims of the crisis has not been progressing.” Another member, Shuya Nomura, criticized Parliament for leaving all decision making to TEPCO and Prime Minister Shinzo Abe’s pro-nuclear Liberal Democratic Party (LDP) administration, rather than overseeing the process. “The public is extremely concerned, especially about the latest contaminated water leak. Many people worry if it’s a good idea to leave the plant up to TEPCO and the regulators. Is it all right to leave the response to contaminated water and other problems to the discretion of TEPCO and the executive branch of the government? As representatives of the people, Diet members should have expertise and get involved with the mindset of the general public,” he said.
In response to the recent leaks, the NRA has ordered TEPCO to find the cause and determine its environmental impact, adding that it may increase monitoring at the Daiichi plant. Nevertheless, analysts say that TEPCO continues to respond to crises only after they occur, rather than proactively working to prevent them. For instance, the company set up a task force to address water capacity issues at the plant, but only did so this week, two days after the leaks in holding tanks occurred.
TEPCO is currently working to transfer water from tank #2 to another tank, a process that will take five days; they hope to finish Wednesday. By that time, an additional estimated 47 tons of highly radioactive water will have leaked into the ground.
Officials insist that none of the water has seeped into the ocean, which lies approximately 800 meters away. Nevertheless, local fishermen remain highly concerned that their livelihoods, already destroyed by the Fukushima disaster, will be further damaged. “I am afraid that we will continue to be plagued by this kind of problem until the reactors are finally decommissioned [40 years from now]…We fishermen are the ones who will have to suffer until the end, due to the increasing amount of contaminated water at the plant,” lamented one fisherman.
In other news, workers have begun to move spent fuel assemblies from a combined storage pool to a depot on the premises of the Fukushima Daiichi plant. The depot will temporarily store dry casks containing the spent fuel rods, which need to be moved from the common pool, in order to make room for spent fuel that will be transferred from the pool at reactor #4 beginning in November.
TEPCO
Prime Minister Shinzo Abe admitted last week that it will be difficult to restart four reactors at TEPCO’s Fukushima Daini power plant, located approximately 10 km from the crippled Daiichi plant, because of staunchly anti-nuclear sentiment by local residents. “Even if safety is secured, it is difficult to restart operations without the understanding of local residents. It is not easy with evacuees still unable to return to their hometowns,” he said. However, he added that TEPCO, rather than the government, should decide whether or not the plant should be permanently decommissioned. Abe, who has been pushing hard for restarting reactors across Japan, was speaking before a Lower House Budget Committee meeting.
Nuclear Regulation Authority
The NRA said this week that it will require nuclear power companies which host reactors within 160 km of volcanoes to assess risks and determine how long it would take to transfer nuclear fuel from those reactors before lava reached them. Experts say that the new ruling will affect the majority of Japan’s nuclear reactors, most of which sit relatively near to volcanoes, and may lead to decommissioning for some.
However, NRA officials also decided to relax new requirements—originally scheduled to take effect in July—mandating offsite control rooms located at least 100 meters away from nuclear reactors. Instead, officials said that utilities will have up to five years to build those, as well as to install remote-controlled cooling systems. In the interim, the NRA said that power companies can use mobile operation centers. The original regulation was prompted by the Fukushima crisis, during which TEPCO officials were unable to use central control rooms to manage the emergency because radiation levels there were too high.
Other Nuclear Politics in Japan
New analysis by the Asahi Shimbun shows that the cost of reprocessing Japanese nuclear fuel has tripled since 1995, from 44 million yen to 122 million yen ($1.28 million), further raising the overall cost of nuclear power. Japan hoped to process nuclear waste by removing plutonium, which would then be used to make new nuclear fuel. However, the remaining highly radioactive waste must be treated via a process called vitrification, in which radioactive materials are encased into glass, in order to more easily disposed of them. Currently, it is a complex and expensive process. Initially, reprocessing was supposed to be done for a short time by Great Britain and France, while Japan readied its own reprocessing facilities at the Rokkasho plant in Aomori Prefecture, slated to open in 1997. However, completion of that facility has gone through 19 delays and numerous technical issues. Meanwhile, the costs of transporting fuel overseas and the vitrification process itself have gone up considerably. The reprocessing plant in Britain has also suffered problems, including leaks of highly contaminated waste.
Yesterday, the government filed suit against protesters who set up tents in front of the Ministry of Economy, Trade, and Industry (METI) building in September 2011 and have been camping there ever since, in an effort to demonstrate against the dangers of nuclear energy. The government is now trying to force the protesters to leave the area. One activist said, “[We] intend to show that this is an important location to conduct a national debate on nuclear power.”
Decontamination
A new exposè by The Mainichi Daily News shows that workers tasked with decontaminating cities and towns near the Fukushima nuclear disaster are living in Spartan conditions and receiving very low pay, as multiple layers of contractors and subcontractors shave off percentages of their wages. Workers are forced to sleep in tiny areas, and most are provided only vegetables to eat, despite working in fields all day, clearing radioactive grass and brush. “We aren’t treated like human beings,” said one worker. “We were treated almost unbelievably roughly, especially as we were doing hard physical labor.” The government mandates that decontamination workers receive 10,000 yen ($100) per day in hazard pay on top of regular wages, but once that’s subtracted, many firms are only paying approximately 1,000 yen ($10) to each worker per day. One contracting firm said, “We did pay the workers danger pay [as required by law] in addition to their pay, but in the absence of a labor agreement with the workers concerning deductions, we subtracted costs for room and board.” Another firm representative noted the difficulty of working with so many layers of contracting and subcontracting firms, each of which takes a share of the profit. He noted, “You can’t really turn a profit unless you hit the workers’ wages or shave them down somehow. In the end, the whole system is designed to make money for the big construction companies at the top.”