At the end of a long day in Japan, there is a striking disconnect between the official statements (at least in the English media) concerning the Fukushima Daiichi nuclear plant and the actions being taken by authorities and the plant’s owners.
Chief Cabinet secretary Yukio Edano has been reported as saying that an explosion earlier today at the Fukushima Daiichi nuclear plant did not occur at the site of Unit 1, despite pretty compelling footage of something that looks like a reactor building exploding. Japan’s nuclear safety authority is reported as saying that the reactor itself remains in tact. “There is no possibility that radioactive substances will have leaked,” Edano added in a televised statement.
The Tokyo Electric Power Company (TEPCO), in a statement, reported “a big sound around the Unit 1 and white smoke” shortly after another quake shook the area. But the company would not confirm whether the reactor itself was involved, saying only that four workers have been taken to hospital.
Those sorts of low-key statements do not match with the actions of the government or the power company. Late this afternoon local time, authorities announced that they were enlarging the evacuation zone surrounding the plant to 20 kilometers in radius. The International Atomic Energy Agency also reports that the Japanese are readying iodine tablets for distribution to the public.
Radioactive iodine is one of the largest health threats from any nuclear accident. The iodine can easily escape in gases vented from the reactor and is readily absorbed by the human body, where it becomes concentrated in the thyroid. Iodine tablets flood the thyroid, effectively lessening the uptake of any radioactive isotopes floating around. In a separate statement, TEPCO reports increased levels of radioactive iodine at the Fukushima site.
Meanwhile, the explosion has apparently prompted TEPCO to try flooding Fukushima Unit 1 with seawater. Such a decision reinforces the urgency of the situation. Nuclear plants are normally cooled with ultra-pure water, as any contamination can become radioactive (as well as interfere with the reactor’s processes). Flooding the reactor with ocean water will almost certainly ruin the unit permanently. As Walt Patterson, an independent nuclear consultant, put it to BBC News: “This reactor will now be a write-off.”
There has also been speculation on BBC this afternoon that the explosion was triggered by hydrogen gas from the reactor core. The gas would be created as water decomposes in the intense heat of the core, and, if that is what triggered the blast, it implies that temperatures are far higher than authorities have let on. There is a possibility that a partial meltdown has already taken place.
I still have not seen any update on Fukushima Daiichi unit number 2 or the two units experiencing difficulties at Fukushima Daini.
Of course, downplaying nuclear emergencies is nothing new, and the authorities do have an incentive to try and minimize panic as they increase the exclusion zone around the reactor. Yet from the evidence we have at the moment, the situation, to me at least, looks far more serious than official statements might lead one to believe.
For full coverage of the Fukushima disaster, go to Nature’s news special.