Fallout from Fukushima: One Year After

It’s almost a year since the massive earthquake and tsunami off the east coast of Japan on March 11, 2011 which triggered the Fukushima nuclear disaster. This note briefly discusses why the nuclear disaster happened, why it is still occurring, the main preliminary lessons, its likely health effects and its political effects in Europe.

Information and new insights about Fukushima are appearing almost on a daily basis. This briefing was updated on March 12, 2012.

The nuclear accident

Following the earthquake, the three operating reactors at the Fukushima Dai-ichi nuclear plant automatically shut down because of huge lateral vibrations caused by the quake. But the quake also disconnected the reactors from the national grid, therefore their cooling pumps could not operate. Emergency diesel-powered pumps kicked in but these were unwisely located in reactor basements which were flooded by the tsunami arriving 40 minutes later. The result was inexorable rises in nuclear fuel temperatures until the fuels melted then started to boil.

Because of the paramount need to remove the large amounts of decay heat from nuclear fuels both in the reactors and in the spent fuel ponds, cooling failures resulted in a compound, cascading series of explosions and other events which are still being unravelled. The major events were as follows:

• core meltdowns occurred in the reactors of Units 1, 2, and 3;
• explosions destroyed the reactor buildings of Units 1, 3, and 4
• an ‘explosive event’ damaged the containment structure inside reactor 2;
• several fires broke out at Unit 4;
• spent fuel stored in the pools of Units 1–4 overheated as their water levels dropped;
• many workers suffered high radiation exposures and often had to be evacuated
• machinery for reactors 1–4 damaged by floods, fires and explosions remained inoperable

On March 12, a probable hydrogen explosion at Unit 1 wrecked the plant, exposed its spent-fuel pool to the open air, released radioactive matter into the environment and caused delays in cooling Unit 3. This probably resulted in its explosion the following day.

On March 13, a much larger explosion occurred at Unit 3 which wrecked the plant, damaged seawater injection lines and vent lines for Unit 2, producing delays in its cooling. It is likely this then caused  “damage” on March 15 to the fuel area inside Unit 2 at about 6 am. Seconds later, an “explosive event” of some kind damaged the spent fuel pond at Unit 4 resulting in a fire in its pond area at about 9 am.

On March 16, at 05.45 am, a third major explosion occurred – this time in the fuel pond at unit 4 – wrecking the unit in its entirety.  No TV video footage of these latter explosions exists as they occurred early in the mornings.

In other words, explosions at one unit hampered responses to the damage at others, leading to a chain reaction of explosions and radiation releases. No wonder the staffs at the plant were often terrified and TEPCO (the electricity utility) wanted to withdraw all personnel from the plant at one stage.

­­­­­­­­­­­­­­­­­­­­Within about six hours of the Japanese earthquake and tsunami, it appears that full or partial nuclear fuel meltdowns had occurred within Units 1, 2 and 3 at Fukushima due to the inexorable heat from radioactive decay in nuclear fuel. This was quickly followed by the molten fuel (at ~2,000 °C) melting its way through the steel pressure vessels into secondary concrete containment vessels. It is now thought these containment vessels have cracked and much fuel is now in the basement areas of the reactors. At the same time, the water in the spent fuel ponds above the reactors also began to boil causing their water levels to drop thus exposing spent fuel to the elements.

So within a few days of the earthquake/tsunami, three major explosions and two “explosive events”had occurred at the Fukushima Dai-ichi Units. The explosions wreaked massive damage with the result that the reactor buildings at Units 1 and 4 in particular may collapse.

It is important to note that the reactor malfunctions, resulting fuel meltdowns and explosions were due to the earthquake as well as the tsunami, contrary to the explanations given by TEPCO and the Japanese regulators which only mentioned the tsunami. See http://www.theatlanticwire.com/global/2011/07/meltdown-what-really-happened-fukushima/39541/ The point is that the many Japanese nuclear reactors near fault lines are considerably more vulnerable to earthquakes than to tsunami.

Ever since the accident occurred, the main preoccupation has been to keep the nuclear fuels cool. This applies not only to the melted nuclear fuels in the reactor cores but also the large volumes in the storage ponds at Units 1, 2, 3 and 4. Fuel in unit 4 was at one stage exposed to air and caught fire, causing one of the three major explosions.

The continuing disaster

A year after the accident, it is still continuing in slow motion and will do so for years. Major efforts are still being made to keep the reactor fuel cool to stop it from melting through the bottoms of the reactor buildings into the soil below, although the concrete bases are ~10 m thick. If this were to occur, Japan would be deep in uncharted waters: further explosions would likely occur. Water is also still being pumped into the storage pools to keep their spent fuels covered.

In addition, it is hypothesised that criticality excursions are recurring in nuclear fuels[1]. It is also becoming known that many nuclear fuel fragments are spread throughout the plant and even as far as the large town of Iitate over 30 km away. A major headache is the structural instability of the wrecked reactor buildings which may collapse at any time due to the massive weight of the storage ponds situated, again unwisely, on top of the reactors. This would spill thousands of tonnes of dangerous spent fuel and radioactively-contaminated water over the site.

In December 2011, nine months after the crisis first erupted, Japanese Prime Minister Noda declared that reactors 1, 2 and 3 were now in a state of cold shutdown and the crisis at the plant had been contained. According to the government and Tepco, the melted nuclear fuel in the wrecked reactor cores was being kept below 100^o C and the leakage of radioactive materials had been reduced. According to the government and Tepco, these were criteria that met the definition of a cold shutdown.However this announcement was met with disdain and many questions in Japanese and international media. Newspaper reports stated that widespread public concern remained on two matters. The first was just how stable the facilities really were – could they withstand other powerful earthquakes? The second was that no one had yet determined the locations of the melted fuels inside the containment vessels or ascertained how badly damaged the fuel rods were. On the other hand, some nuclear experts believe the government’s assessment is  more or less accurate, in that the melted fuel in the reactor cores had stopped generating dangerously high levels of decay heat. See http://www.japantimes.co.jp/text/nn20120308x1.html

When we look further afield the situation is no better, as very large amounts of radioactivity were dumped into the sea and emitted to atmosphere. The latter resulted in about a thousand square km of land being contaminated with fallout and large amounts of crops and produce being contaminated. An estimated 100,000 people have had to be evacuated from their homes, possibly for decades. These effects are on top of the estimated 20,000 people killed by the earthquake and tsunami themselves. The situation is truly numbing and our hearts go out to the Japanese people struggling with the horrible consequences of the earthquake/tsunami and of the Fukushima disaster.

How long will this dire situation continue? It’s hard to say, but IAEA officials privately talk of years: other scientists say decades. Up until recently, contaminated water from the cooling operations was being dumped on land and into the sea. Nowadays this water is mainly being pumped into large temporary holding tanks.

Health Effects

Few deaths have been recorded at Fukushima so far, certainly in comparison to the thousands caused by the earthquake/tsunami. About 7 deaths to military personnel and plant operators were apparently caused by the site explosions. According to an NHK (TV) survey, 68 patients from evacuated hospitals died during the long hours of evacuation. None of these deaths were due to radiation exposures. But fears remain about longer-term effects, as radiation has decades-long latency periods before most solid cancers appear. Increased incidences of thyroid cancers – a prominent effect after Chernobyl – are unlikely to appear for another three years.

It is too early to make firm predictions, but judging from the exposures and effects seen at Chernobyl, it’s likely that at least a few thousand fatal cancers will occur among those exposed to Fukushima’s radioactive fallout. In addition, it’s likely that Fukushima plant workers will suffer as the Japanese Health and Labor Ministry reported that nearly 100 workers had exceeded legal radiation limits by June 2011.

Main Conclusions

Fukushima is clearly a serious disaster but it is not as serious as Chernobyl. Radioactive air emissions are much more important than radioactive sea discharges in terms of their  radiation doses to people, and the dispersed radioactivity to air from Fukushima has been estimated to be about 10% to 40% of the amount dispersed from Chernobyl. About a thousand square km near the Fukushima were contaminated, but at Chernobyl the area affected was much larger: over 200,000 square km throughout Europe were seriously contaminated by fallout, according to the European Commission.

A very recent report[2] by the Japanese chairman of the independent Rebuild Japan Initiative Foundation is recommended. It reveals many institutional failures at Fukushima and shows that TEPCO and the Japanese government and its nuclear agencies were completely unprepared for the disaster at almost every level. This lack of preparation was caused by the myth of absolute safety that nuclear power proponents had nurtured over decades. It was aggravated by poor communications and lack of trust within and between government agencies and TEPCO. Interestingly, the report also shows that the disaster, bad as it was and is, could have been worse. Apparently, luck and serendipity were on the side of the Japanese at several junctures during the disaster.

Perhaps the simplest of the lessons to be learned from Fukushima is that nuclear power is a supremely unforgiving technology. When things go wrong, they can go very, very wrong with consequences which are difficult or almost impossible to remedy. But nuclear power is merely a complicated way of boiling water and, after Fukushima, many countries are beginning to examine safer energy policies.

The Political Fallout in Europe

Interestingly, different countries have responded in diametrically opposite ways to the Fukushima disaster. In the UK, the coalition government, most political parties and many parts of the media appear to be ignorant of, or perhaps in denial about, the continuing events at Fukushima. Certainly most of the UK press and the BBC are heavily pro-nuclear in their outlooks. The result is that the UK is the most strongly pro-nuclear country in Europe. This was starkly illustrated on July 18, 2011 when only 14 out of 650 UK MPs voted against the government’s Nuclear Policy Statements. In contrast, two weeks earlier, on June 30, the German Parliament voted by 513 to 79 to phase out all nuclear power by 2022.

The UK government’s nuclear bias was also shown when FOI requests in July 2011 revealed deep collusion between the government and the nuclear industry. Apparently civil servants in energy and business departments attempted to minimise the impact of the Fukushima disaster on public support for nuclear power by leading and co-ordinating a misleading PR response to the Fukushima disaster with the nuclear industry. In 2011, the UK government did request the Chief Inspector of Nuclear Installations to report on the implications for British reactors from Fukushima. But with a few caveats, his final report was a whitewash for nuclear power: the Government’s plans for up to eight new nuclear power stations were little affected.

In France, which nowadays obtains ~73% of its electricity from nuclear reactors, the nuclear worm appears to be turning. An opinion poll in June 2011 showed 75% wishing to withdraw from nuclear energy vs 22% backing nuclear expansion. The French Presidential and Legislative elections in May and June 2012 respectively are currently expected to result in a Socialist President and a PS-Green coalition government formally opposed to nuclear power.Francois Hollande the PS leader has promised to phase out one-third of France’s nuclear fleet by 2025 andthe Socialist Party has called for a moratorium on new reactors and pledged a national debate on energy transition if elected.

In Germany, several  250,000-strong demonstrations took place after Fukushima with the result that major reversals occurred in regional (Lände) elections and opinion polls on the nuclear issue showed large increases in opposition to nuclear power. Weeks after the tsunami, the Merkel government decided to permanently close the eight oldest reactors it had already taken off-line and to close  the remaining nine over the next 11 years. Stiff anti-nuclear windfall taxes have also been imposed on nuclear power companies. These policies are very popular with 75% of Germans in agreement in various opinion polls.

In Germany, politicians have started taking energy efficiency seriously: the German government now plans to reduce electricity demand by 25% by 2050 through energy efficiency. In contrast, the coalition government in Britain is planning for electricity demand to increase by 25% over the same period.

In Italy, an astonishing 94% of those voting in a national referendum in 2011 opposed new nuclear which forced the (then Berlusconi) government to abandon its nuclear plans. In Switzerland, 25,000 attended an anti-nuclear demonstration, and the Swiss cabinet decided against new build: in effect supporting a phase-out programme as its old plants retire.

With Austria, Denmark, Portugal, Norway, Ireland and Greece all non-nuclear and phase-out programmes in Spain and Belgium, only four major EU countries – UK, France, Finland and Sweden – remain supportive[3]. But with nuclear problems in Finland[4] and the situation in France shifting, it is little surprise that French and Germany nuclear companies look to the UK as a safe haven for new nuclear projects – with the Con-Dem coalition offering enthusiastic, not to say slavish, support.

It is a sobering thought that on the nuclear power issue after Fukushima, the UK appears to be increasingly out-of step with the majority of its European Union neighbours.