Tuesday AM:The complete exposure of the fuel rods in the Daiichi No 2 reactor core overnight will cause a meltdown unless the they are re-submerged with an effective coolant. The extreme urgency of this need is the reason for the government of Japan to plead for immediate international assistance in overcoming new difficulties that the nuclear industry keeps insisting would not occur.
10.10 am: Ambiguity continues over government references to the No 2 reactor container being ‘damaged’ by an explosion earlier this morning. Spokespersons announced the presence of ‘damage’ in the reactor before they confirmed there had been an ‘explosion’ and are having difficulty confirming that the two confirmations are linked. They are also saying there has been no increase in radiation at the reactor, a claim which is being contradicted by references to increased radiation in other briefings this morning.
The known factual situation this morning is that all three Daiichi reactors that were active when the earthquake and tsunami occurred last Friday have now suffered explosions, and that the ‘container’ of No 2 reactor has been suffered unspecified damage. The government and Tokyo Electric company have previously emphasised that the internal reactor containers surrounding the No 1 and No 3 cores have not been structurally damaged.
There has been another major explosion at the Fukushima Daiichi plant in the No 3 reactor, which is fueled by plutonium oxide and uranium oxide.
Get Crikey FREE to your inbox every weekday morning with the Crikey Worm.
The No 1 Daiichi reactor lost its roof and most of its outer walls in an explosion on Saturday afternoon. It is fueled by uranium rods.
The explosion occurred just after a helicopter crew was reported as having sighted a three metre high tsunami wave front racing toward the Honshu coastline. That report has since been withdrawn as false by media in Japan.
The International Atomic Energy Agency this afternoon reported that all four reactors in the Daini plant now have stable water levels and that radiation levels monitored over a 16 hour period for that complex are normal. It said that while preparations to vent steam to relieve pressure at these reactors had been made, no venting had occurred.
This report (below) , about what matters in the nuclear crisis part of the vast devastation caused by Friday’s earthquake and following tsunami in the north Pacific coast/Sendai region of Honshu appears on Crikey today.
It has taken less than three days for Japan’s notoriously dishonest and evasive nuclear industry to concede the seriousness of the crisis affecting the Fukushima Daiichi and Fukushima Daini plants NE of Tokyo with six and four reactors respectively.
But the ferocious debate over nuclear power that has erupted in the media outside Japan is completely missing several points.
The first point is that the failures of ‘fail safe’ cooling processes at each plant is a risk analysis bet gone wrong by Japan’s nuclear power regulators and the Fukushima plant owner Tokyo Electric.
The second point is that the calamities unfolding at the nuclear plants will not kill anything like the 10,000 or perhaps far more people now officially believed to have died in the massive tsunami that ravaged low lying areas of Honshu’s northern Pacific coast on Friday afternoon after a magnitude 8.8 earthquake occurred near Sendai at 2.46 pm local time.
This is likely to be true even if several completely uncontained meltdowns of reactor cores were to occur, despite the extreme seriousness of such events.
When the tsunami overwhelmed the separate coastal locations of the Fukushima Daini and Fukushima Daiichi plants they had already begun shutting down in an automated response to the earthquake, the most powerful ever directly recorded in Japan.
It was the fail safe backup cooling processes that failed, because they had deliberately been designed and built to withstand severe yet less extremely severe natural disasters.
This was a money saving risk analysis bet by Japan’s nuclear regulators and the owners that a combination of such an extremely violent earthquake and following tsunami would not occur in its lifetime.
That bet nearly came off. The older Daiichi plant has only weeks to run on its 40 year operating licence and half of its reactors were already off line and are reported to be undamaged in their shut down state.
Until about 9 am local time on Saturday Tokyo Electric, the Japan Government, and nuclear apologistas world wide were insisting that the there had been no melt downs in the reactors, that there was no risk to public safety, and that mass media comparisons to the Chernobyl melt down in 1986 were flawed, which in terms of design is certainly true.
It was even claimed that only if such desperate measures as flooding the reactor cores with sea water took place would the situation be serious.
Shortly afterwards it became apart that nuclear fuel rods exposed by falling levels of coolant in the Daiichi No 1 reactor were initiating partial meltdown with the release of ‘slightly’ radioactive steam from the reactor block and admissions that caesium contamination had been found outside the plant, indicating that the outer layer or cladding of the uranium rods had crumbled and been ejected into the environment during the ‘harmless’ steam releases.
Then the outer retaining walls and roof of the Daiichi No 1 reactor were violently blown to smithereens, a process the Chief Secretary for the Cabinet, Yukio Edano, described as a ‘roof collapse’.
While the Japan government continued to evade the seriousness of the situation it was flying in emergency consignments of unspecified coolants, possibly additional supplies of boric acid, which absorbs neutrons and thus acts as a liquid alternative to control rods in a reactor core in which fuel rods and control rods have been partially melted or otherwise damaged to the point where they cannot be used.
The language of officialdom began to shift rapidly from benign soothing evasions to urgency throughout Saturday and yesterday until this morning when Prime Minister Naoto Kan specifically referred to the nuclear plant situations as ‘grave.’
It appears that up to seven reactor cores, the total that were active in the Fukushima complexes, have been or are about to be flooded with seawater and injected with boric acid, both previously described by nuclear apologistas as ‘desperate measures’ not justified in the post tsunami crisis yet which will according to nuclear scientists, irreparably damage the reactors in the course of shutting them down when all else has failed.
As of this morning the smallest figure given for the number of people in hospital for radiation exposure is 90 and the population at large is being given potassium iodine tablets which will pre-empt the absorbing by the thyroid gland of radioactive iodine particles which was confirmed yesterday afternoon as having escaped from the Daiichi complex some 24 hours after the authorities grudgingly conceded the presence of caesium fallout.
In the drip feed of disclosure coming from Tokyo Electric and the government, it is now publicly confirmed that the fuel rods in the Daiichi No 3 unit, which is of most immediate concern as being at risk of an explosion, use a combination of plutonium oxide and uranium oxide, not just the uranium that was being used in Daiichi No 1.
The fission process using only uranium fuel does produce plutonium, however the addition of plutonium oxide at the start of the process lifts the output of a reactor while substantially adding to the lethality of the sort of failure that the nuclear industry regulator and Tokyo Electric knew was possible but gambled would not occur.
This morning there was an elevated radiation level emergency declared at the Onagawa nuclear plant, which comprises three reactors, and is 120 kilometres from the NE outskirts of Tokyo, compared to about 240 kilometres for the nearest Fukushima plant.
These fluctuations at Onagawa are now attributed to fallout from the Fukushima ‘releases’ which is not comforting to those in Tokyo or elsewhere in Japan but is an inevitably that adds to the far more visible and immediate aftermaths of the tsunami.