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Mycle Schneider1 for Physics and Society
Three years after the Fukushima disaster was triggered, the situation at the site remains worrying. High levels of radiation lead to difficult working conditions and still render human access to the reactor buildings impossible. Huge, constantly increasing quantities of highly radioactive water and contaminated wastes need to be stored, treated and disposed of. However, their management still appears to be improvised, following short-term considerations without coherent long-term concepts. Radioactivity continues to be released into the environment, mainly into the groundwater and into the ocean. Over 150,000 people remain evacuated, many of them in provisional housing, most of them without any prospects to go back to their homes. Dose limits have been increased in order to suit the environmental conditions rather than being determined to protect peoples’ health. And the dramatic further increase in radiation releases remains a credible scenario until the radioactive materials in reactor cores, spent fuel pools, water and waste have been stabilized and disposed of. This is expected to take decades.
Hans Blix, former Director General of the International Atomic Energy Agency, called the Fukushima catastrophe “a bump in the road” of nuclear development. The statement illustrates not only a remarkable level of arrogance and a rather exceptional cynicism towards the victims of the disaster that lost everything, but a startling loss of reality. The Fukushima events hit an industry that was already struggling to maintain the status quo prior to 2011 (see The Status of the Nuclear Industry in the World – Dawn or Dusk? in the April 2014 edition of this newsletter). While the Fukushima Prefectural Assembly passed a resolution in favor of a nuclear-free prefecture six months after the disaster started unfolding, it took the operator TEPCO until December 2013 to officially abandon Fukushima Daiichi (1) units five and six. The four Fukushima Daini (2) units, 15 kilometers from Daiichi and inside the evacuation zone, remain officially “in operation”, although they have not generated power since March 2011 and will most likely never come back online. In fact, none of the Japanese reactors have generated power since September 2014, only two throughout the year 2013. The average outage time of the 48 reactors that are still accounted for by the International Atomic Energy Agency (IAEA) as “in operation” is over three years, as the World Nuclear Industry Status Report 20142 documents. The fate of the shut-down reactors is all but certain. As of 10 June 2014, eight nuclear power companies have applied to the Nuclear Regulation Authority (NRA) for safety assessments of 19 nuclear reactors.3 While the Abe administration is committed to the earliest possible restart of as many reactors as possible, in early July 2014, it looks as if at best the two Sendai reactors in Kyushu could restart before the end of the year. In the meantime, former Prime Minister Junichiro Koizumi and a member of Prime Minister Abe’s Liberal Democratic Party, declared on 7 July 2014: “The logic of those who have promoted nuclear power generation has completely failed” and announced: “I will lead a national campaign to reduce the number of reactors to zero.” Combined with a large majority of the Japanese people and local authorities around nuclear sites opposing restarts, Koizumi will not make it any easier for the stranded program to get back up and running.
The triple disaster earthquake-tsunami-nuclear accident on 11 March 2011, frequently referred to as 3/11, triggered a chain of events of unprecedented proportions. Three reactors at the Fukushima Daiichi site 60 km from the city of Fukushima experienced core meltdowns. The reactor buildings of units one, three and four — the latter was not operating at the time of the earthquake — were also severely damaged by hydrogen explosions. If over 150,000 people were evacuated, an unknown number of people self-evacuated and 2,000 km2 were turned into an exclusion zone. Recent announcements of the first lifting of evacuation orders for a few hundred people that could return to an area at the edge of the 20 km evacuation zone cannot cover up the fact that most of the evacuees will likely never be able to return home, if not under hazardous conditions. The lifting of evacuation orders comes at the same time as the announcement by TEPCO to end compensation for people who suffered loss of or reduced income. Obviously, both measures are aiming to limit soaring costs of the disaster. The most far reaching measure in this context is the post-3/11 decision to increase the admissible radiation dose from external sources — thus not including internal exposure through contaminated food and inhalation — by a factor of 20 from 1mSv to 20mSv per year.4 This brings the dose limit for the public, including pregnant women5 and small children, to the level of selected, trained nuclear workers.
Some aspects of the situation on-site are getting better, but many issues remain critical or are actually getting worse. The good news is that unloading of spent fuel from the pool of unit four has started in November 2013 and as of 23 April 2014 almost half of the spent fuel assemblies (726 of 1533) had been removed and transferred to the common spent fuel pool on site. The spent fuel pool of unit four was and remains of particular concern as it contained about as much fuel as the other three reactor pools together and less cooled fuel, as the entire core was in the pool during the 3/11 events while the reactor vessel was undergoing maintenance and inspection. A major leak of the pool or its collapse with a subsequent spent fuel fire was seen as the “worst case scenario” already two weeks after 3/11. The Japan Atomic Energy Commission then calculated that up to 10 million people potentially would have to be evacuated, including from an area around Tokyo, under such a scenario with unfavorable wind conditions. The fuel unloading from unit four is expected to continue for the entire 2014 year. The same work remains to be done on the other three units and is expected to take until 2023. Meanwhile, thousands of tons of debris and rubble have been removed from the reactors and their immediate environment. Covers have been installed on the units whose roofs were blown off by hydrogen explosions and provide some protection against severe weather impact.
On the other hand, many aspects are worsening. Likely amongst the biggest challenges is the task to maintain the integrity of the infrastructures, whether buildings and storage tanks or several kilometers of pipes and tubing, etc., which are permanently exposed to seawater atmosphere, typhoons and heavy rain. Surface vinyl tubes are exposed to frost in the winter and have experienced numerous leaks.
Significant amounts of water, about 350 m3 per day, have still to be injected into the three reactor buildings in order to cool the molten cores. This water is contaminated by the damaged fuel and, since the containment buildings are fractured, leaks into the basements. Under the nuclear site runs an underground river that originally had been deviated from the building infrastructure. However, that engineered deviation was destroyed by the earthquake and since then an estimated 400 m3 per day push into the basements and mix with the highly radioactive water from the core cooling. While some water is taken out of the basements, decontaminated to some extent and re-injected for cooling, in order to avoid massive, permanent overflow, an amount at least equivalent to the quantity of groundwater pushing in has to be taken out. In other words, an additional 400 m3 have to be pumped out of the basements, decontaminated to some degree and stored every day, which means that one 1,000 m3-tank is filled up every two and a half days. The water decontamination system has its own multiple problems ever since it was put into operation and is currently out of service. As a result, highly contaminated water is increasing steadily, to 440,000 m3 by end of 2013, four times more than in September 2011, of which about 350,000 m3 in over one thousand tanks and the rest in the basements of the reactor buildings. The amount of cesium-137 in the basements alone is estimated at about 1.5 times the quantity released into the environment at Chernobyl in 1986 or ten times more than released at Fukushima during the first weeks of the event in 2011. The water storage capacity is to be increased to a staggering 800,000 m3 by the end of the year.
The storage tanks are sitting on poor, non-earthquake proofed concrete foundations that have already shown substantial cracks. More than 300 tanks, each of them containing about 1,000 m3 of highly radioactive water, are bolted rather than welded together. In the fall of 2013, the Nuclear Regulation Authority (NRA) requested replacement of the bolted to welded tanks, but this will take a long time. Many of these tanks do not have volume gauges, so leaks are difficult or impossible to detect. Leaks are, however, frequent. In several occasions, TEPCO admitted that highly contaminated water has reached the ocean. In the future, it is planned to color the contaminated water as to simplify the visual identification of leaks and avoid confusion with rainwater puddles. Increased numbers of “patrol” staff should also allow for more rapid leak detection. The lack of well-designed, automated supervision comes at the price of increased radiation risks to workers.
Another complex area is the storage and disposal of the huge quantities of sludges and filters from decontamination activities as well as other solid contaminated wastes. The management, transport, storage and disposal of the high activity filters and sludges can be expected to be part of major future challenges.
All these activities require human intervention. Tens of thousands of workers have gone through the site. In an overview dated 30 August 2013, the Japanese Health Ministry indicated a total of almost 29,000 people that have been employed at the nuclear site. Less than 4,000 were TEPCO employees, while 25,000 were contractors and countless levels of sub-contractors. TEPCO has increasing difficulties finding new workers that can replace the ones that are leaving, either because they are demoralized or because they exceeded the official dose limit. The press agency Reuters has identified 733 companies performing work under environment ministry contracts and 56 subcontractors “listed on environment ministry contracts worth a total of $2.5 billion” in the most contaminated areas of the Fukushima exclusion zone. In a staggering investigation6 Reuters illustrates how homeless people have become the target of headhunters for work in the contaminated areas. Many illnesses that might develop amongst Fukushima workers are unlikely to ever be reported.
The extraordinary complexity and the unprecedented scope of the challenges that the long-term stabilization of the Fukushima site represents have early on led to the proposal of the establishment of an International Task Force Fukushima7. This type of permanent group of top-level experts in the key fields at stake would elaborate strategic recommendations for short-, medium- and long-term measures. Conceived as a concerted international initiative, the group would have access to a large network of additional experts. Many people around the world support the basic idea but an institutional partner or initiator in Japan remains the essential missing piece. As they say: you can’t push a rope.
Excerpts from upcoming World Nuclear Industry Status Report 2014:
Due to shortage of tanks and area to store the water, in early 2013, adjacent to the tanks TEPCO dug seven large (10,000-ton-class) sink ponds, which were easier to make and at lower cost. But a series of radioactive leakages was detected in March and April 2013. On 5 April 120 tons of radioactive water leaked from this reservoir.8 This released the highest amount of radioactivity since December 2011 when the damaged reactors were declared to be in “cold shutdown”.
In June 2013, it was revealed that the groundwater sampled from a monitoring well adjacent to the Unit-2 turbine building is contaminated with strontium and tritium, so the highly radioactive water that filled the unit basement had already made its way to the aquifer, hence it can easily flow into the sea.9
On 20 August 2013, TEPCO announced that about 300 tons of contaminated water leaked from a tank and that while a part of it was held back by a small dike around the tanks, the rest went underground and contaminated the soil.10 The radiation level measured 50 cm above ground was roughly 100 mSv/h.11 The contamination level was measured at 100,000 Bq/l of Cesium 137 and 80 million Bq/l of Beta emitting radionuclides. In this context the NRA decided to rate this event at level-3 of the International Nuclear Event Scale (INES) rating.12
On 20 February 2014, TEPCO announced that another significant leakage of contaminated water had occurred at one of the bolted tanks. Apparently, 102 tons containing 230 million Bq/l of Beta and 9,300 Bq/l of Cesium 137 were leaked.13 It was the biggest reported leakage since August 2013, and TEPCO is investigating its cause. Some early findings indicate that a valve that was supposed to be closed was left open and the water in the tank overflowed. If this was the case, it would hint towards an operator error, and could be due to limited expertise of the staff.
1 Mycle Schneider is an independent international energy and nuclear policy consultant, based in Paris. He is the convening lead author of the World Nuclear Industry Status Reports and a member of the Princeton University based International Panel on Fissile Materials (IPFM).
3 JAIF, “Nuclear Power Plants in Japan (In operation and under construction)”, 10 June 2014, see http://www.jaif.or.jp/english/news_images/pdf/ENGNEWS02_1402531967P.pdf, accessed 11 June 2014; see also, Reuters, “Factbox-outlook for japan nuclear reactor re-starts”, 2 April 2014, see http://in.reuters.com/article/2014/04/01/japan-nuclear-restarts-idinl4n0mt0k020140401, accessed 6 June 2014.
6 Reuters, “Special Report: Japan’s homeless recruited for murky Fukushima clean-up”, 30 December 2013; See http://www.reuters.com/article/2013/12/30/us-fukushima-workers-idUSBRE9BT00520131230
9 The contamination was confirmed in late May 2013, but it took TEPCO more than two weeks to publicly release the information, see TBS News, NHK News, Mainichi Shimbun, 19 June 2013. Also see http://enformable.com/2013/06/tepco-confirms-fukushima-daiichi-groundwater-contaminated-with-strontium-and-tritium/, accessed 20 June 2013.
10 TEPCO, 20 August 2013, see http://www.tepco.co.jp/en/nu/fukushima-np/handouts/2013/images/handouts_130820_03-e.pdf
11 http://www.tepco.co.jp/en/nu/fukushima-np/handouts/2013/images/handouts_130821_07-e.pdf, accessed 2 May 2014.
12 NRA, Press Release, 28 August 2013, see http://www.nsr.go.jp/english/newsrelease/2013/0828.html, accessed 7 June 2014.
13 NRA, News Release, 20 February 2014, see http://www.nsr.go.jp/english/newsrelease/data/20140220.pdf accessed 7 June 2014 and TEPCO, Fukushima Daiichi NPS Prompt Report 2014, 20 February 2014, see http://www.tepco.co.jp/en/press/corp-com/release/2014/1234394_5892.html, accessed 7 June 2014.