Saturday, January 12, 2013

Nuclear Updates

There is so much going on here that it is difficult to keep up. I don't want Kurashi to be all about nuclear issues, since there are so many other topics that interest me, and inspire. But I also work with related issues, so here we go.

The Guardian: Fukushima 50: 'We felt like kamikaze pilots ready to sacrifice anything

Excellent article by Justin McCurry over at The Guardian, just about the best I have read so far in the English-language press about what actually happened at Fukushima Dai-ichi after the March 11, 2011 earthquake and tsunami. He has managed to interview one of the workers who stayed on to save us all from a much bigger disaster.

Disagreements over a possible withdrawal rumoured to have taken place in the capital never filtered through to the men on the frontline, according to Yoshizawa. Some among the vast network of Tepco contractors and subcontractors ordered their employees to leave the plant. They were joined by other workers who lived in the communities in the path of the tsunami or which were imperilled by the reactor meltdowns. None of the workers had been able to communicate with their families; some would return to find their homes had been swept away. But at no point was anyone forced to stay, Yoshizawa said.
"I never thought of leaving. I had to stay and get a grip on the situation. I wasn't thinking about my family, only about the other workers and how worried they must have been about their own families.
"We knew that we would not be replaced. No one was forced to stay, but those of us who remained knew that we would be there until the end. We knew that we were the only people capable of saving the plant. Our determination surpassed all other considerations."
Yoshizawa says the hardest part of his job was sending junior colleagues into dangerous situations. The plant was frequently rocked by strong aftershocks, and the proximity of so much water to electrical equipment was an ever-present danger, as was the risk of acute radiation sickness.

The Mainichi: Over 10 nuclear plants in Japan have flawed fire-prevention equipment: sources

You couldn't make this up if you tried. If you were writing a Science Fiction novel, perhaps, but this is what we are finding out now, almost two years after the Fukushima disaster.

More than 10 nuclear power plants in Japan are plagued by flaws in their fire-prevention equipment, nuclear regulatory sources have revealed, raising the possibility some reactors may be shut down.
Sources close to the secretariat of the Nuclear Regulation Authority (NRA) and the Ministry of Economy, Trade and Industry (METI), respectively, say that deficient equipment includes flammable electric cables in wiring. They say apparatuses important to safety are also installed close to each other, increasing the risk that fire could spread from one apparatus to the other.
The Agency for Natural Resources and Energy has already launched an investigation into the matter, while the NRA is poised to interview electric company officials in the near future.
METI anticipates that some nuclear reactors may be decommissioned due to the high cost of exchanging cables and repairing equipment. It also expects that reactivation of other plants could be delayed by several years.
Since December 1975, utilities obtaining approval for reactor construction have been required to use flame-resistant cables in important safety equipment and to appropriately space apparatuses to prevent fires from spreading. However, due to the absence of regulations for reactors built before then, the decision on whether to improve such equipment has been left up to each plant operator.
The total number of plants using flawed equipment has not been determined, but the Mainichi Shimbun interviewed power companies across the country and found that cables made of such flammable materials including vinyl and polyethylene are used at 13 out of 50 nuclear reactors. Because the surfaces of those cables are coated with fire-resistant agents using special types of resin, utility officials say they are on par with flame-resistant cables. However, the NRA secretariat and METI officials dismissed the utilities' claims.
"Even if the fire-resistant agents do not burn, the flammable cables inside would burn," one source told the Mainichi. "Those cables may also be aging and deteriorating. We can't recognize them as being equivalent (to non-flammable cables). Most of the cables are fraught with problems in terms of fire prevention and need to be renewed."
At some plants, it has also emerged that equipment controlling the so-called reactor "safety system," which includes control rods, the core cooling system, and instrument surveillance at the time of a nuclear accident are flawed in terms of fire-prevention measures. Although the principle of "system separation" that allows one failed electric system to be complemented by another one is prioritized in safety systems, at some plants electric cables for two separate systems are installed in close proximity. Cooling water pumps are also set up next to each other, raising the risk of such critical apparatuses catching fire simultaneously. Both the NRA secretariat and METI officials are expecting that such flaws will be found at more than 10 reactors.
The NRA is planning to include both the "system separation" rule and stipulations on the use of flame-resistant cables in new safety standards to be drawn up by July. However, as each reactor has roughly 1,000 to 2,000 kilometers of cables, including several hundred kilometers which are important to safety, it will take more than one year and cost a huge amount to renew the cables. Due to the prospect of unrecoverable costs, some reactors may be forced to be decommissioned, the sources said.

The Asahi: Hamaoka reactor likely wrecked in seawater accident

A similar accident happened in the US at the Unit 1 reactor of the Millstone nuclear power plant in Connecticut in September 1972, so experts know this is serious.

A restart may be impossible at one of Japan's idled nuclear reactors without substantial repairs, after an accident during a shutdown procedure last year in which hundreds of tons of seawater flooded equipment including the central pressure vessel.
Unrefined seawater contaminated sensitive appliances and subsequent inspections have found rust on many key components of the affected unit, the No. 5 reactor at the Hamaoka nuclear power plant in Shizuoka Prefecture. Damaged devices include those that regulate the rate of nuclear fission.
The incident occurred while workers were shutting down the reactor on May 14, 2011

Japan Today/Fuji TV: Rice grown in Miyagi contains more than double legal limit of radioactive cesium

Probably a case of "hot spot" radiation - it is good to see that it was caught by the careful testing that is on-going in the Tohoku region. While it is worrying to some extent, the levels are not really dangerous. But the comments at Japan Today indicate that a lot of people are worried and angry, nevertheless.

Rice grown in Miyagi Prefecture was found to contain more than double the legal limit of radioactive cesium, the Ministry of Agriculture, Forestry and Fisheries announced Friday.
The rice, which was grown on a farm in Kurihara last year, was found to contain around 240 becquerels per kilogram of radioactive cesium, over twice the legal limit of 100 becquerels per kilogram. Fuji TV reported that this is the first time rice grown outside Fukushima Prefecture has exceeded the legal limit.
The local government has requested farmers growing rice in the same ward as the affected farm to check each bag for radiation before shipping. It added that it will strive to carry out spot checks on rice from neighboring prefectures.
In order to quell public fears about rice already shipped from the farm in question, a ministry spokesperson said that spot checks had, until now, given no cause for alarm.

The Japan Times:  As radiation fears dwindle, so do checkups, Doctor wants more residents to get followup full-body scans

Good article by Mizuho Aoki with insights about efforts to check internal exposure radiation level. Dr. Masaharu Tsubokura has set up a clinic to help people get tested, but as no high levels are found, fewer people are showing up to get tested.

As residents have come to understand more about radiation and that their internal exposure levels are low, an air of calm has been noticeable. At the same time, residents' interest in knowing their exposure levels has waned.
"I'm surprised to see such a dramatic loss of interest in just about a year and a half," said Tsubokura, 30, who works several days a week at Minamisoma hospital and the rest of the week at the University of Tokyo. "The biggest issue we have now is finding ways to secure continuous checkups for internal radiation exposure."
The city of Minamisoma covers the cost for two checkups. The hospital there began conducting the second round of internal exposure examinations in August, but less than 3 percent of residents tested in the first round turned up that month, Tsubokura said.
"To be honest, local people have almost no worries (about radiation exposure because of eating contaminated food) these days. . . . They are satisfied with their results from last year (where many were below detectable levels)," Tsubokura said.

It's not just Japan, folks, South Korea is going through an extensive overhaul of its reactors, too. In November, 2012, cracks were found, and thousands of parts at their reactors were revealed to have been supplied with false documentation. Reuters noted that the head of the main electricity utility KEPCO resigned as the scale of the scandal hit the news.

Reuters: South Korea widens nuclear lapses probe; KEPCO chief resigns

Two reactors remained shut on Wednesday, and five others are closed for maintenance, or through other glitches, raising the prospect of winter power shortages. The nuclear industry supplies close to a third of South Korea's electricity.
The authorities have stressed that the parts - such as fuses, switches and heat sensors - are non-crucial, and there is no safety risk.
Kim Joong-kyum, president and CEO of power utility Korea Electric Power Corp (KEPCO), which owns the operator of the nation's nuclear plants, tendered his resignation for what KEPCO officials said were "personal reasons". 

(...)


South Korea's Nuclear Safety & Security Commission said it set up a team of 58 private and public investigators to inspect all the country's reactors to see if they were supplied with parts with forged certificates.
"The team will inspect all 23 reactors, which will take some time, as you can imagine," a spokeswoman for the commission, which supervises nuclear safety, told Reuters. The commission said it plans measures to improve supply systems, quality controls and external auditing.
Eight companies submitted 60 false certificates to cover more than 7,000 parts used in the two reactors between 2003 and 2012, and Economy Minister Hong Suk-woo told parliament that most of the documents, which purported to come from certifying body UCI, were forgeries.
A senior ministry official told Reuters that UCI was one of 12 U.S. certifiers, but was not one of the eight firms under investigation. The firms have not been named.




Over at Consumers Union of Japan, we are thinking about the roles of consumers and producers. Amagasa Keisuke writes:

Contaminated food is a particularly serious matter for young children and pregnant women, with possible consequences for coming generations as well. The consumer movement and anti-nuclear power plant activists have pointed out similar problems resulting from the Fukushima Dai-ichi nuclear plant disaster after the March 11, 2011 earthquake and tsunami in northeastern Japan.
However, there is another aspect to the meltdowns here in Japan. After Chernobyl, farmers and consumers in Japan did not take steps to cooperate and deal with radioactive contamination, in spite of the fact that agricultural lands and the ocean were polluted. After the Fukushima disaster, farmers and consumers have ended up divided on the issues, as the perpetrators – the government and TEPCO – have strongly continued to promote nuclear power over the years.
For over 40 years, the consumer movement demanded Japan to abolish nuclear power plants in order to avoid accidents. What is our role now? Even I could never imagine such a situation after an accident has actually occurred.

Finally, for Japan Focus, I was asked to take an extended look at all of the 50 or so nuclear power reactors from Hokkaido to Kyushu, trying to develop my blog post here earlier, and assess if any of them at all are safe, or not. My conclusion?

Japan Focus: Getting to Zero: Doing the Nuclear Math about Japan's Ageing Reactors

As for nuclear reactors in Japan, there are 13 or fewer, possibly none, that are "maybe safe" and most of them are in western Japan. As I finish writing this paper, I keep wondering what new incident may happen, what discovery of another active seismic fault may come to light, and all kinds of revelations about more problems with Japan’s Nuclear Village, that may render this whole calculation terribly redundant. As I found out, it is not just that there are lots of issues with the links: The entire chain is the problem.


(Top image by Tore Davidsson, from Koke-dera, Kyoto, November 2012)






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