30 August 2013

A summary of what is going on at Fukushima as of 30 August 2013.

The biggest 'fallout' for the higher ed sector has been the collapse in the numbers of students applying for nuclear-energy-related programs at universities (e.g., the one at University of Fukui, where I work--and University of Fukui and the prefecture are in deep with the nuclear power industry for money while the prefecture hosts more reactors than any other in Japan, 13 of the 50 in the country). The two reactors now operating (the others are still shut down) are in Oi, in southern Fukui Prefecture.


Fukushima, Japan update Charles Jannuzi in Fukui, Japan

A lot of alarming reports and comments are appearing in the western media about the situation at the Fukushima Dai-ichi nuclear reactors in NE Japan. They largely echo what has been appearing in the media here in Japan.

Are things getting so out of control that they will affect the health and well-being of not only the Japanese but other Pacific Rim nations, including the west coast of the United States? Is the escaping contamination from Fukushima going to turn off sushi eaters in the US? (Elevated levels of cesium have been reported in tuna as far away as California).

Let's try to untangle the contamination and leak issues that have been in the news a lot recently. What are the sources of the reported leaks?

It seems that the issue is actually THREE issues:

1. They have been storing a lot of the water that they pump into the stricken reactors to cool both the piles of depleted fuel rods (which take years to cool down properly) and the melted down cores. The excess water from these cooling operations they have then been attempting to filter in order to decontaminate. What they can not decontaminate and recycle for cooling they have been storing in hundreds of makeshift tanks above ground. It appears that some of the tanks have not held up well and have been leaking.

2. Four of the six reactor buildings at the site are heavily damaged from hydrogen explosions and from the melting down of the cores (which may have punched holes in the bottom of the containment). This has made the reactor buildings leaky. So any water pumped in to cool rod piles and core material may leak out into the ground.

3. It's not really clear from reports just what are the states and locations of the cores of three of the reactors. The three that have melted down might have escaped the final bottom layers of containment and lodged in the ground beneath the reactor buildings. If so, groundwater working its way through from the hills above the site could also be coming in contact with radioactive materials from the melted down cores and contributing to the contaminated water problems. Also, the reactors that exploded expelled core material into the air, which may have come down around the reactor site, and this material too could be working its way into the ground water or at least the water that flows out of the site into the sea.

On the positive side, there is right now little danger of radioactive materials escaping into the air and moving on the wind. It's mostly an issue of what is in the water at the site.

There is, however, another dangerous problem. This is the large, elevated pool filled with fuel rods that had been taken out of Reactor 4 before the disasters. This pool is in danger of collapsing because the support structures around it are weakened from the explosion while the reactor building itself is subsiding.

If the storage pool were to collapse and there were a loss of coolant, the rods could overheat and cause radioactive leaks into the air again. Since it is a very large amount of spent fuel, such an incident could, in theory, threaten cities downwind of the site, including the Kanto/Tokyo metropolitan area of 35 million people to the south.

Should Americans living on the west coast be worried about the leaking radioactive materials flowing around the Pacific? So far, the ocean has dispersed and diluted most of the contamination. However, contaminants such as cesium and strontium may not just disperse the way the ocean currents take them. If they end up in food chains (from plankton to small fish, from small fish to larger fish, etc.), they could accumulate and show up in the Pacific fish and seafood that Americans eat.

Cesium acts a lot like potassium, so eating potassium-rich foods (such as avocadoes and bananas) can help displace cesium in the human body. Similarly, strontium acts a lot like calcium, so a diet rich in calcium can help displace strontium.The Fukushima Daiichi reactors used MOX fuel, which includes plutonium. Some plutonium has been detected well away from the reactors, which indicates it was expelled when the reactor buildings exploded and burned. 

The biggest challenge now facing Tepco and the government of Japan is not really the immediate clean up of the Fukushima site. Rather the challenge is to get the site into stable enough shape in order for real clean up to proceed, with clean up taking up to 50 years or more.

For that to happen, they will have to somehow stop or divert the groundwater that flows under the site, since this groundwater could be coming into contact with core material in the ground and then flowing into the ocean.

There have been calls from overseas for Japan to allow for an international effort to help at Fukushima, but Japan is a country that prides itself on self-sufficiency in such matters, and teams from overseas would be expensive to house, feed, supply and provide interpreters for, while they might not really have the expertise that the disasters require.

Part of the problem is that former Soviet countries have the experience with a severe disaster (that is, Russia and Ukraine with Chernobyl), but the reactors in Japan are an American design--the GE Mark I boiling water reactors (BWR), also in heavy use in the US and other parts of the world. Russia and Ukraine do have expertise in the use of purified Prussian Blue to lower the levels of radioactive cesium in humans and animals that may have breathed, eaten or drunk it. But relations between Japan and Russia have deteriorated recently. The US military is said to be sitting on a large stockpile of Prussian Blue, but there have been no reports of them offering to supply it to Japan.

Meanwhile, government policies under PM Abe have brought some relief to the ailing economy (Abenomics). But for example, the intentionally cheaper yen that has helped Japan's famous exporters (like Toyota, Nissan, Canon and Sony) has also made imported oil and gas much more expensive. Before the disasters, nuclear energy had provided over 30% of Japan's electricity needs. Japan is a country of 127 million people that must import about 85% of its total energy needs.

There is now a lot of pressure from the power companies to get the government to allow them to re-start most of Japan's 50 reactors while continuing the construction of new ones. During the recent hot summer there were reported energy shortages but no major blackouts. Power plants burning oil, gas and coal have taken up the slack. Public buildings have kept their thermostats set at a rather warm 85 F to conserve energy, which at least has led to a boom in Cool Biz clothing for office workers.    

However, 80% of the public oppose any re-start of the reactors. Despite this opposition, Oi 3 and 4 here in Fukui Prefecture have been in operation since the summer of 2012, providing electricity to the Osaka/Kansai metropolis area.

Unfortunately, it seems the Fukushima nuclear disasters and energy troubles are going to remain in the news for years to come.

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