The fallout from TEPCO's informational blunder last week, continues. While all experts on the phenomena agree the Xenon discovered in unit #2's Primary Containment is due to spontaneous fission, many admonish TEPCO for needlessly causing fears and creating doubts about the Company's level of expertise...
Koji Okamoto, a professor of nuclear engineering at the University of Tokyo, supported spontaneous fission, "I also calculated the amount of xenon from the data that TEPCO released and found it was about the same as the amount produced due to spontaneous fission." However, Fumiya Tanabe, director of
the Institute of Nuclear Safety Systems Inc. suggest TEPCO's handling of the issue indicates deep administrative problems, “The problem is that TEPCO pointed to the possibility of 'criticality'
taking place, if only temporarily," and, "It eventually showed that the utility failed to predict the situation of fuel rods or the present internal state of the reactor.” (Asahi Shimbun)
Katsutada Aoki, formerly of the Atomic Energy Society of Japan, also criticized TEPCO saying the utility could have avoided needless fears. Aoki said, "The discovery of xenon in the reactor is no
reason to fear anything serious. Chances of a criticality taking place is practically [unthinkable] at this point." He then added, “TEPCO's initial announcement and later downplaying of the possibility of a criticality event only adds to the impression that the firm does not have the situation under control.” Meanwhile, TEPCO made another attempt to mitigate the situation when a spokesperson said, "We only mentioned [nuclear criticality] because the analysis was incomplete at that point and there was a
possibility [of such a scenario]. It's regrettable that it caused unease since the word 'criticality' is easily misinterpreted as a serious condition by the public." (Japan Times) In other words, TEPCO went public before fully understanding what they were saying.
There has been a recent barrage of insidious and aggressive viruses attacking Japanese government and military (Self Defense) computer systems. The source of the onslaught has been traced to a remote
region of China, but the exact location is unknown. Considerable informational “leaks” have been discovered, and serious damage has been done to some operating systems. Last week, the government
asked all nuclear utilities to report if they have been attacked. It turns out three of them have detected attempts to infect their systems, but firewalls have stopped them. (NHK World)
Tatsuhiko Kodama, head of the Radioisotope Center at the University of Tokyo, has begun a detailed survey of the radiation levels inside the 20km no-go zone around Fukushima Daiichi. Accompanied by “some journalists”, Kodama found that small parts of the southern zone were at less than 0.23 microsieverts per hour, the national standard for decontamination. Levels soon increased to 0.45 microsieverts as they drove north. Moving closer to the power complex, radiation levels naturally increased, with a 10 microsievert reading in the towns of Okuma and Futaba and 22 microsieverts near the power plant property boundary. At the southern edge of Minamisoma the reading was 0.36 microsieverts, but the town's levels decreased to 0.1 microsieverts as they neared the northern no-go zone border. Lastly, Kodama surveyed a fishing port of Namie, just six kilometers from the power complex, and the reading was 0.08 microsieverts. "Rather than drawing lines uniformly by distance, the central government
should examine radiation levels in detail and decide to allow people to enter the evacuation zone to do decontamination or construction work," Kodama said. (Mainichi Shimbun)
TEPCO has begun the removal of Cesium isotopes from spent fuel pool (SPF) #2. While the concentrations of Cesium are many times lower than the waste waters in the turbine basements, its removal from the SPF
water will speed up the process of removing salt caused by seawater sprays in March and April. Salt content is about one-tenth of seawater levels, but it could accelerate corrosion of the steel walls and supports inside the pool. (JAIF)
Some further information from the Kansai Electric Company's stress test data concerning Ohi unit #3... The report claims Ohi's tsunamic protection factor has been increased by 145% since March, emergency
power supply longevity has been upgraded so the core can be cooled for 16 days without outside power sources, and emergency safety margins have been increased by a factor of 75. Details are not available. (JAIF)
A recent Environment Ministry survey found that only 54 of the more than five hundred municipalities in Japan have said they will accept tsunami waste and rubble from Miyagi and Iwate Prefectures. The
reason? Vocal residents who fear that the waste might contain radioactive materials from Fukushima. The complaints are based on distrust of government health standards and the belief that any detectable Fukushima isotopes pose a health hazard. More than 20 million metric tons of untainted rubble is left in these two prefectures, giving off foul odors and causing fires. Unless the rubble from these areas is disposed of across Japan, it will undoubtedly hinder disaster recovery efforts. Many residents of
disaster areas say they feel depressed when they see the mountains of wreckage in their neighborhoods nearly eight months after the disaster. (Mainichi Shimbun)
Tokyo Governor Ishihara has lashed out at those who have protested his government for saying they will dispose of rubble from Miyagi and Iwate Prefectures. Ishihara says they received 2,868 phone calls
and e-mails as of Nov. 2, protesting the rubble disposal scheme. Only 199 were in favor. "What are we going to do if we do nothing?" Ishihara asked, "Those capable of helping must help. They (opponents) care only about themselves.” He added that if these phone callers are indicative of the Japanese
public-at-large, then, “It is proof that the Japanese people have gone bad." He then explained what happens before the rubble is shipped to Tokyo, "They are not bringing in rubble incessantly emitting radiation. They are bringing it in because checks (for radioactive contamination) have proved there is nothing wrong with it. Tokyo is not that foolish." (Mainichi Shimbun)
Nuclear Accident Minister Goshi Hosono has said that tsunami-caused rubble and debris in Miyagi and Iwate Prefectures is not radioactive and incineration of the burnable material will not produce anything
Hosono has also announced the government will investigate into the risks of low level radiation exposure below 20 millisieverts (msv). He acknowledged there is no statistical evidence of negative health
effects below 100 msv, but public concerns with the government's initial 20 msv exposure limit has driven the new investigation. He added there have been numerous conflicting studies about low level
exposure risks and the investigation might ease the controversy. (JAIF)
Radioactivity has been found in the urine of some Fukushima children. Out of more than 1,500 samples of children under 6 years old, 104 had detectable levels of Cesium. None, however, came anywhere near the national standard. All but one detectable sample showed 20 to 30 becquerels per liter, which is barely detectable. The other was 187 Becquerels, but even that is 3 times lower than the standard. (NHK World)
The international Press is focusing on news reports out of Japan about recriticality in the damaged fuel of reactor #2 at Fukushima Daiichi. The Japanese Press is calling for a complete revision of the “cold shutdown” criteria, and the world's Press is drooling over it. As it turns out, what was discovered and reported to the Press has nothing to do with the process known as “criticality”. The whole mess could have been avoided if it were not for the ineptitude of TEPCO's public information staff, exacerbated by speculations made by some of TEPCO's remarkably naïve nuclear officials.
All uranium-based fuel experiences the process of spontaneous fission. It's a property of elements with atomic masses greater than 232, where the nucleus of the atom will split all by itself. The probability of spontaneous fission is extremely low for U-238, but not too low to be detectable. Uranium is not the only element in nuclear fuel that spontaneously fissions at a detectable level. The other is Curium.
Curium is not a naturally-existing element. It is produced in small quantities during reactor operation and slowly builds up in the fuel pins (~20 grams per ton of spent fuel). Here's a summary of the production process...U-238 has a tiny probability of fission, but it does absorb neutrons. U-238 neutron absorption transmutes it into the element Plutonium through natural radioactive decay (Alpha and Beta). Some Plutonium is isotope 239, some Pu-240, and some more Pu-241. It is the Pu-241 which further absorbs neutrons and subsequently transmutes into Curium. Curium isotopes 242 and 244 have a probability of spontaneous fission.
All fissions produce any of about 42 possible elements (see “Nuclear Waste : Is it?”), which are known as fission products. One of the most probable fission products is Xenon, and its two most probable isotopes are Xe-133 and Xe-135. Xenon is an inert gas, which chemically combines with nothing, so it has little trouble migrating out of the fuel and into the surrounding environment, in this case the inside of the Primary Containment of unit #2 at Fukushima. The tiny amounts of Xenon discovered by TEPCO on Wednesday strongly indicate the process of spontaneous Uranium and Curium fission, with Curium's probability 10-50 times greater than Uranium's. Recriticality would have produced Xenon in volumes 1,000 to 10,000 times greater.
When they told the Press, TEPCO let everything get out of control from the very start. They said the Xenon having come from recriticality is “unlikely” due to all the boric acid in the water injections, when actually the source had nothing to do with criticality and could not be inhibited by boric acid. In other words, the notion of recriticality was not “unlikely”, it was unquestionably impossible! TEPCO has yet to learn two of the basic nuclear facts of life. First, anything that can be misinterpreted to the extreme, will be. The word “unlikely” means “possible” to the Press and their readers. In some cases it is taken to mean “inevitable”. Second, never release information through people who haven't got a clue, and the TEPCO Press staff has repeatedly shown a high degree of “cluelessness” with respect to nuclear realities since March 11. The same can be said for some of TEPCO's officials who make public statements about things they obviously know nothing about.
The following updates exemplify what we are saying...
On Wednesday, TEPCO spokesperson Hiroki Kawamata said ““We cannot rule out the possibility of a small nuclear fission reaction.” Thus, the Press assumed that fissioning had resumed inside RPV #2. (Japan Today)
Junichi Matsumoto, acting director of TEPCO's Nuclear Power and Plant Siting Division, told a press conference a small scale fission reaction is likely to have occurred in RPV #2. "We don't believe criticality has been maintained," Matsumoto said. Which led the newspaper to speculate “TEPCO suspects a nuclear fission chain reaction took place caused by existing neutrons within the reactor or that very local criticality took place as the water temperature in the reactor decreased and water density increased, due to the recent increase of water injection.” (Yomiuri Shimbun)
- Mainichi Shimbun's lead editorial on Thursday calls for a complete revision of the cold shutdown criteria, based entirely on the re-criticality issue. The editorial first says, “The government and Tokyo Electric Power Co., the operator of the tsunami-hit Fukushima No. 1 Nuclear Power Plant, should step up their monitoring of the plant's reactors to check whether nuclear fission is occurring and provide good explanations of the situation in the reactors to the public...we mustn't let down our guard. The government and TEPCO need to find out why the fission has occurred and take appropriate responses.” Then later concludes, “The government and TEPCO have announced their intention to bring forward the timing of achieving a so-called "cold shutdown" of the crippled reactors in their roadmap to bringing the nuclear plant under control...However, the discovery of xenon in the No. 2 reactor's containment vessel suggests nuclear fission is occurring even though the temperature at the bottom of the pressure vessel is thought to be below 100 degrees Celsius. It raises questions as to whether such a reactor can be considered stable, even if it is under that temperature threshold.”
- Thursday, TEPCO did its best to recover from its PR gaffe, but the damage was already done... “The Tokyo Electric Power Company, or TEPCO, said on Thursday that the small amount of xenon-135 it detected in gas taken from the reactor's containment vessel was the result of the spontaneous nuclear fission of radioactive curium-242 and -244.” (NHK World) But... Japan Today writes “The operator of Japan’s
crippled Fukushima nuclear plant on Thursday played down fears of an uncontrolled chain reaction at the site, despite the discovery of evidence of recent nuclear fission.” TEPCO spokeswoman Chie Hosoda said the amount of Xenon detected was about 10,000 times less than what would be found with re-fissioning or recriticality. The Japan Today report immediately reminds the reader that this contradicts TEPCO's announcement the day before.
Before we relate some other updates, we want to point out that for enough Xenon to be released into the Primary Containment to be detectable, it is improbable that the source is a completely melted fuel cell. If completely melted, the re-solidified corium material would bee too massive and dense to allow sufficient Xenon migration for detectability of the type found Wednesday. On the other hand, a partially, if not severely melted fuel cell would have enough exposed surface area to emit detectable levels of Xenon. Just one more clue that unit #2 might not have fully melted.
Now, for other updates...
- The radioactive bottle of Radium buried outside a Tokyo supermarket was broken and its contents mixed liberally with the surrounding soil. After all bottle shards and surrounding soil were removed, the radiation field dropped from the initial 40 millisieverts down to 25 microsieverts, a reduction factor of more than 1,000. (Asahi Shimbun)
- The discovery of two hot spots not due to Fukushima has brought a warning from the Tokyo government. "Because many radioactive materials had not been under control before the country set up a law, there could be an increasing number of such cases", one official said. Tokyo advises anyone finding what appears
to be a new hot spot should report it to the Ministry of Science as soon as possible. (Japan Times)
- Although the government tried to collect all Radium quantities from 1965 to 1974, it is now obvious they missed some. Most of the privately held vials and jars of Radium were given up voluntarily during that period, but some were not because the owners had either personal or sentimental attachments. "In some cases people stored them away carefully, saying they were family treasures. It remained a fact that the  law hadn't seeped in," said Yoshihide Nakamura, an official from the Japan Radioisotope Association. In addition, prior to 1965, government inventories of Radium were not well documented. But, it might not only be Radium, "There are a lot of old substances, such as those that university professors purchased overseas and left behind when they retired without others realizing," said Takao Nakaya, head of the Radiation Regulation Office of the Ministry of Education, Culture, Sports, Science and Technology. (Mainichi Shimbun) What do people do when they want to get rid of something strange? Either toss it in the garbage or bury it somewhere. Thus, the Japanese are finding hot spots, and the process will continue.
- Japan Times runs an editorial Q&A about the biological effects of radiation exposure. Unfortunately, it's the same old song and dance about the effects of low level exposure being unknown, concluding, “Experts
just don't know the effect on humans below 100 millisieverts.” Perhaps the most heinous fallacy concerns mention of the studies done on the high-background Kerala region of India. The Times first states, “No correlation was found between the ambient radiation and the risk of cancer,” then follows with, “Just
because studies haven't found a statistically significant increase in risk doesn't necessarily prove there is no chance of an increase in the cancer rate.” The Times tries to justify their spin by evoking BEIR VII (2006) which uses the mentally-confounding notion of relative risk derived from the statistically-corrupt Linear/ No Threshold concept. Why? Because Kerala has an annual exposure rate higher than most of the communities inside the Fukushima evacuation zone, like Iitate and Namie, which might lessen public fears. There is no mention whatsoever of Mortazavi's discoveries with Ramsar, Iran, where natural backgrounds are greater than 250 millisieverts per year, up to 5 times the exposure levels found inside the no-go zone. But then, we're dealing with fear of radiation in Japan, which has become very good business for their Press and food for the rest of the world's Press that loves nuclear energy. Loves nuclear energy? Yes! Any and all scary-sounding nuclear stuff makes immediate headlines. It's an automatic money-maker. Of course they love it.
- The source of the high radiation level near a Tokyo, Setagaya Ward supermarket has found it to have nothing to do with Fukushima. After tearing up the asphalt overlying the location of the source, technicians dug down nearly a foot into the soil and found a bottle containing material suspected to be Radium. Soil analysis revealed isotopes of Lead and Bismuth, two radioactive decay daughters of Radium. Contact reading on the bottle was 40 millisieverts (4 REM) per hour. The bottle was placed in a lead-lined box and sent to the Science Ministry for further investigation. With the removal of the bottle, radiation levels in the area dropped back to those found elsewhere in the ward. (Mainichi Shimbun)
- TEPCO has announced there may have recently been a short period of increased fissioning inside the fuel cell of reactor #2. When analyzing gas from inside the Primary Containment surrounding the RPV, two isotopes of the inert gas Xenon were detected; Xe-133 and Xe-135. Each has a short half life, with Xe-133’s being five days and Xe-135 being nine hours. These isotopes cannot be residuals of the March 11 emergency shutdown, thus they must have come from a recent refissioning. The concentrations are miniscule, so it is likely the rate of fission was very, very low. Whether or not the fuel cell experienced brief re-criticality is speculative. Even if it did, the fission rate at temperatures below 100 oC would be tiny. Not even enough to measurably raise the water temperature. TEPCO is sending their data to Japan’s Atomic Energy Agency for review and confirmation. TEPCO has increased the level of boric acid in the RPV water injections to prevent this from recurring. They are also checking units 1 and 3 to see if something similar has happened. (NHK World; Mainichi Shimbun) What none of today’s reports mention is a fully melted and relocated fuel cell makes something like this highly unlikely. However, a partially melted cell could possibly give us something like this. Is it possible that unit #2’s fuel cell did not experience a full meltdown?
- In a related story, Professor Koji Okamoto of the University of Tokyo Graduate School says the possibility of recriticality in a melted fuel cell being cooled by water full of boric acid is unlikely. He says, however, that pieces of melted fuel “scattered around” that are in the natural neutron field surrounding nuclear fuels might produce some low level fissioning. He concedes the presence of xenon in the No.2 reactor leaves open the possibility that localized and temporary fission could occur. Okamoto stresses that a self-sustaining chain reaction that creates criticality is unlikely in a boric acid environment. (JAIF)
- The Mayor of Genkai, Saga Prefecture, has given approval for the re-start of Genkai unit #4, which was shut down due to an operator mistake about a month ago. "I am persuaded to some degree," Hideo Kishimoto told reporters after talks with Kyushu Electric Executive Vice President Haruyoshi Yamamoto. The Nuclear and Industrial Safety Agency rated the utility's report on the cause of the shutdown and error-prevention measures they have taken as "basically appropriate," which seem to have satisfied the Genkai Mayor. Because the shutdown was due to human error, the stress test required for other idled nukes is not needed. (Mainichi Shimbun)
- Following the Genkai Mayor’s positive response, Kyushu Electric has begun restart of Genkai #4. Operating preliminary functions prior to the resumption of electricity production will be later today. Kyushu Electric plans on full 1,200 Mwe output to the national grid by Friday. (JAIF)
- After months of gloomy stories about Asian nations turning away from Japanese foods due to fear of Fukushima radiation, we find that the food scare may have ended months ago. At least in Hong Kong, Japan’s largest consumer of Japanese foods. Hong Kong’s Japanese restaurants took a terrible downturn in April. "People simply lost confidence in eating Japanese food, especially fresh food like sushi," said Simon Wong, chairman of the Hong Kong Food Council. Diners slowly began to return around the end of May, and by late August business for most Japanese restaurants and supermarkets specializing in Japanese food had recovered. Wong said, "Actually, some restaurant owners told me that they are getting even better business than before March 11." Yata Ltd., a popular Japanese-style store, also saw its fresh produce business recover after overall sales plunged at least 70 percent in April and May. Yata Managing Director Daniel Chong said, "In August, when we started selling Japanese peaches, they were immediately sold out. We are already above last year's sales record (for peaches)." (Japan Times) If the recovery has been happening in Hong Kong since August, why has it taken until November for a Japanese news source to report the good news?
- Japan Nuclear Energy Safety Organization (JNES) under the jurisdiction of the government's Nuclear and Industrial Safety Agency (NISA), is being charged with “sloppy inspection procedures”. Yoshihiro Nishiwaki, a visiting professor at the graduate school of the University of Tokyo, has revealed, "Inspections are carried out by the government itself, and therefore they should make painstaking efforts to determine the content of inspections on their own." It seems that JNES, the principle nuclear regulatory inspection body, did not write their own inspection procedures, but rather cut-and-pasted instructions from nuclear plant manuals. Also, instead of performing their own inspections, they would have the utility operating the plants run them and then get the data generated by the plant staff to be analyzed. From 1991 through 1993, Nishiwaki was sent to America to observe Nuclear Regulatory Commission (NRC) inspection processes while working in the Ministry of International Trade and Industry (now defunct). He found NRC inspectors decided on when and what they planned to inspect on their own and often conducted inspections without advance notice. Connecting their own computers with the local area network, they even check e-mails exchanged between facility workers and subcontractors. If necessary, they bring in their own inspection equipment to see if devices at the nuclear plant have deteriorated. All this to prevent nuclear plant operators from doctoring inspection documents. "I was impressed with the attitudes taken by inspectors to check master inspection procedures on their own and try to uncover problems and illegal practices at nuclear facilities," Nishiwaki said. However, there are no such fail-safes in the JNES system. He says Japan’s plant operators carry out inspections first and then JNES inspectors check to see if the examinations are sound by using almost the same techniques as the plant operators. JNES defends their shoddy practices by saying, "There is no problem even if we prepare inspection procedures in accordance with the draft steps prepared by the plant operator." Also, the timing of inspections is notified to plant operators in advance. While working for MITI through 2002, Nishiwaki observed trouble in which some devices were not operating properly during inspections of a nuclear power plant. "When we asked them to show us maintenance records, a worker said to us, 'We will have them operational for sure. Please have sushi or something with our executives until then.'” Nishawaki added he was troubled by such practices, but could find no governmental support to correct the obvious problem. (Mainichi Shimbun) Once again, we find the American regulatory system is many times better than the one which seems to have been the case in Japan for at least two decades.
We have finally found a down-loadable copy of the completed enclosure surrounding unit #1 reactor building...
TEPCO announced they have nearly doubled the cooling injection flow to RPV #1. It is now 7.5 tons per hour, versus the previous flow of 4 tons per hour. This has been done to insure there will be no steam production, which could hamper work inside the new enclosure due to high humidity.
The Tokyo government has designated Fukushima Prefecture as the site for a temporary contaminated material storage area. The exact location has yet to be assigned. Environment Minister Goshi Hosono told Fukushima Governor Yahei Sato the government will set up the facility and plans on being ready to accept material in 2015. Sato was non-committal, saying he wanted to study the Ministry's proposal in detail. Most of Fukushima's 59 mayors have issues with the plans, although no details have been released. "To be honest, we cannot accept it," said Katsuya Endo, mayor of Tomioka, where the Fukushima Daini is located. "It will cause serious damage to our regional development." Endo's comments exemplify the opposition positions. (Asahi Shimbun)
In a related article, some local people have expressed relief that decontamination will continue, while others are adamantly opposed to having a storage facility built in their hometown. There are places where decontamination has not been carried out due to the difficulty of finding temporary sites for storing contaminated soil and waste because local people oppose the construction of a storage sites near them due to radiation fears. Many are bewildered as to why contaminated soil and waste must be stored for 3 years in the prefecture. On the other hand, some welcome the decision...sort of. "I think three years is acceptable," said Haruo Sato, 65, a farmer in Date, Fukushima Prefecture. "I won't tolerate anything longer. I'm worried that the period might be extended to four years, five years...." (Yomiuri Shimbun) Not In My Back Yard (NIMBY) issues raise their ugly head, once again.
Now that the first “stress test” results for the Oi #1 nuclear plant have been submitted, it seems that even if it passes NISA scrutiny, it might be spring before a restart is possible due to political delays. The remaining 10 operating nukes will all be shut down for maintenance and refueling by then, leaving Japan without any operating nuclear capacity. By the numbers, this will produce a further 9.2% shortfall of electricity supply, in addition to the existing shortages. The government says everyone will have to further conserve, but a poll of 230 Japanese businesses shows that only 1% can further reduce consumption before cutting output. Only 2% of non-manufacturers said they could further conserve before restricting business hours. (Yomiuri Shimbun)
A new re-calculation of the amount of Cesium released by the Fukushima accident has been making the news media circuit, both in Japan and around the world. Andreas Stohl of the Norwegian Institute for Air Research says the Japanese may only have accounted for the Cesium released over land , and not out to sea. Thus, instead of 15% of Chernobyl's Cesium, it could be as much as 40% of Chernobyl. The journal Atmospheric Chemistry and Physics posted the report online for comment, but a formal review by experts in the field has not completed, nor has it been accepted for formal publication. In other words, not verified. Regardless, the scary-sounding data is making headlines. Stohl points out two things found near the end of each article. First, making a speculative conclusion like this should not be considered significant, given that estimating uncontrolled radioactive release volume is an inexact science. Second, only 20% of the released Cesium fell on Japanese land. He mentions in the report that Cesium releases dropped considerably when water was sprayed into one of the Spent Fuel Pools, which was probably due to the spray stripping water-soluble Cesium from the air. But, the news media speculates the Cesium may have come from melted fuel bundles in the spent fuel pool.
The Institute for Radiological Protection and Nuclear Safety in France has reported that 30 times more radioactive Cesium was released to the sea from the Fukushima accident than what has been admitted by TEPCO and the Japanese government. How this extreme amount was calculated is not in the Japanese article (Mainichi Shimbun) nor to be found on the IRSN website. We will keep looking, though.
Another relatively extreme hot spot has been discovered, this time in the Setagaya Ward, Tokyo. The spot was found at the conjoinment of an asphalt street and cement sidewalk. The reading at one meter above the spot is 170 microsieverts per hour, some three times greater than last week's previous record of 57.5 microsieverts (contact) reading in another Tokyo ward. Because the source is clearly underneath the asphalt and cement, which has been there for years, the Science Ministry says it is unlikely to be from Fukushima. There is no record of any underground drainage lines in the area, either. The Ministry will have the asphalt torn off and dig into the ground beneath to find the source. (NHK World) As we have posted several times before, the Japanese have no idea about their inland natural background levels, and are totally naïve of localized sources in their communities that have been there for a long, long time. Now they're finding out. It's just starting. We hope the Press will have the decency to point out that these sources haven't hurt anyone.
Now that the Food Safety Commission has caved to fear of radiation and will lower food radiation limits by a factor of five, they are being lambasted by the Press for setting the limit at the lowest theoretical level for cancer incidence, rather than many times below it. The Press asserts children are harmed by radiation more than adults, so lowering the standard even more should be done to protect the kids. Mainichi Shimbun says the new limit should be lowered by a factor of 10, from 1 millisievert per year down to 0.1 millisieverts. Regardless, the Press reaction in Japan over the new food standards going into effect in April is clearly further evidence they feel the only safe level of radiation exposure is none at all. Further, the 1 millisievert per year exposure limit is equal to what is considered as Japan's “normal” natural background level. So, if 1 millisievert per year is unacceptable, is Japan's natural environment unacceptable?
The first article we've seen concerning the impact of the tsunami's seawater on near-coast farmland was posted Saturday. It is estimated that 240 km2 of farmland has been made unusable due to salt contamination in six prefectures along the northeast Honshu Island seacoast. The government estimates it will take three years to desalinate the soil through continuous fresh water flushing. Unlike surface stripping of soil for the removal of Cesium, the seawater soaks deeply into the soil so that the salt has permeated down as far as the topsoil goes. The only way to get rid of it is through continual dilution over a long period of time. None of this has anything to do with Fukushima, but it does tend to put contamination issues in perspective. (Asahi Shimbun)
The first results of a nuclear “stress test” were submitted today. Kansai Electric submitted the results of a stress test on the Oi No.3 reactor in Fukui Prefecture. Kansai Electric mentioned their results showed the plant structures and cooling systems could survive quakes nearly 2 times the worst ever recorded for their region, and a tsunami 4 times greater than an historical worst case. NISA says it could take them months to assess all the data and decide the fate of Oi #3. Then, the results will have to be copied to all local governments and explained in detail before the plant could possibly be restarted. (NHK World)
Japan Atomic Energy Agency and the National Agriculture and Food Research Organization may have found a possible solution to the contaminated soils issue. They placed 10 kilograms of Cesium-laced soil in an oven and heated it to 800 oC for ~10 hours. Cesium evaporates at 640 oC, so most, if not all of the contamination should have left the soil. This process is not burning, but is rather termed “high temperature roasting”. The team used nuclear grade filters on the outlet of the oven to trap the evaporated isotopes. The soils and filters must now be analyzed for efficiency of the process. "Soil would no longer have to be treated as waste if its cesium content could be brought down to a fraction of what it was," said Minoru Okoshi, a senior principal engineer at the JAEA. "We hope to investigate if it could be reused as farmland soil." (Asahi Shimbun)
A group of Japanese researches believe they have created the world's first hand-held decontaminator. The project has been under way for more than seven years, and was originally intended for routine nuclear plant decontamination practices. The hand-held unit is 30 centimeters high and wide, and 40 centimeters long. Although the team has only given the most basic explanation in order to protect their idea, the device uses laser beams to loosen surface contamination, then vacuums the dust into a high efficiency filter. Since only the surface is scraped off, the machine generates one thousand times less radioactive waste than conventional methods. The researchers want this device to be field tested at Fukushima Daiichi. (JAIF)
Japan's Nuclear safety Commission estimates that it could take until 2015 to remove all the fuel bundles from the Spent Fuel Pools (SPF) of units 1-4. After that, it could be 2022 before the actual removal of damaged/melted fuel from units 1-3 RPVs can begin. The SPF's have little or no fuel damage so they will be emptied of fuel cells first, using special cranes for units 1, 3 & 4. Since unit #2 experienced no hydrogen explosion, spent fuel will be removed using installed equipment. Next, robots will be used to decontaminate the interior of the reactor buildings before damaged parts of the containment vessels can be repaired. After that, the containment vessels can be filled with water so that the work to recover melted nuclear fuel can begin. (Mainichi Shimbun)
TEPCO has decided to not build underground retaining walls between the plant buildings and groundwater. Why? Because groundwater always flows towards the nearest large body of water, which in this case is the Pacific Ocean. Thus, local drinking and irrigation waters are not in danger of contamination from the 77,000 tons of waste waters still in the turbine basements. Further, the “quay” adjacent to the power complex has been completely barricaded from the sea, so any leakage out of the basements will be into a contained area. Lastly, the flow is now understood to be from the surrounding groundwater and into the basements, not vice-versa. (Mainichi Shimbun)
Kashiwa City officials in Chiba Prefecture have warned their residents of a decontamination scam. Residents might be deceived by anyone passing themselves off as a local government official, offering to measure and remove radioactive substances for money. A man has been putting fliers in mailboxes telling residents he is from the municipal government. He reportedly offers to measure radiation for 5,000 yen and remove radioactive substances for 10,000 yen. The local government has nobody doing this, and the prices quoted are far below the cost that designated decontamination firms charge. A 57-year-old business manager of a radiation measuring company operating in Kashiwa said, "You can't do decontamination work for that kind of (cheap) price." He added, "We don't want to be lumped in with the fraudsters." (Mainichi Shimbun)
On the other hand, the city of Kashiwa has done nothing with the hot spot discovered a week ago, caused by a broken cement drainage line. The city says they can find no-one to attend to the problem because of the high (57.5 microsievert) contact reading after digging 30 centimeters into the soil. The exposure level at one meter above the ground is 2 microsieverts. "It's difficult to find a company to decontaminate [the site] given the extremely high level of radiation," a city government official said. "The situation is more than we can handle as a local government." In other words, they want the Tokyo government to handle it. (Yomiuri Shimbun) All they have to do is have someone in full anti-contamination attire dig the material up, bag it, and bury it deeply where there is no pedestrian traffic. What's so tough about that?
The Health, Welfare, and Labor Ministry will officially lower the internal exposure limit for food and drink in April. The current limit is 5 millisieverts per year. The new limit will be 1 millisievert per year. "The current provisional safety limit, which was set in response to emergencies, is safe enough, but it will be tightened in order to ensure increased food safety and security," Health, Welfare and Labor Minister Yoko Komiyama said. The Ministry explains they based the change on background research showing long term health effects are theoretically possible at 100 millisievert exposure, thus 1 millisievert per year will keep everyone below this threshold. "Under the current provisional safety limit, consumers are experiencing increased anxiety as they watch radiation measurements. Tightening the safety limit will reassure many people," said Hisa Anan, secretary-general of the National Liaison Committee of Consumers' Organizations. (Asahi Shimbun; Mainichi Shimbun) Will it really reassure anyone while “detectable is dangerous” news stories abound? This remains to be seen.
On Monday, 200 pages from the TEPCO accident procedural manuals used for Fukushima Daiichi nuclear power plant were made public by NISA. The manual was originally given to NISA by TEPCO with nearly everything blacked out. This submittal was unedited. As it turns out, NISA finds nothing in the manuals that indicate any of the procedures were violated by the operating staffs of units 1 through 4. TEPCO has maintained that they did not anticipate a complete loss of electrical power for extended periods, so there were no procedures for such extreme accident conditions. The manual verifies TEPCO did not envision a prolonged power failure. Thus, the manual itself was completely useless when all power sources were actually lost. The company assumed that in a serious situation, existing emergency power sources were sufficient in order to vent pressure from the reactor and containment vessels, as well as power emergency pumps, coolers and condensers. (Mainichi Shimbun; JAIF)
Instructions in the manuals were all based on the assumption that two backup direct current batteries at unit 1 would keep working throughout any emergency. But, the batteries were knocked out by seawater when the monster tsunami struck. The manuals also failed to instruct workers to manually open critical valves normally powered by electricity to relieve excessive pressure in the containment vessel. The DC batteries were supposed to supply power to operate the valves. TEPCO's over-confidence in the batteries convinced them that manual valve-operating procedures were unnecessary. (Japan Times)
While this announcement is treated as something specific to TEPCO by the Japanese Press, there is no reason to believe any of the Nuclear Power Station accident procedural manuals in Japan addressed a prolonged electrical blackout prior to March 11. Have any nuclear utilities in Japan revised their emergency procedural manuals to address a prolonged station blackout since then? This is an issue that cries out for investigation.
Masahiro Fukushi, professor of radiation science at Tokyo Metropolitan University, says the recent discoveries of localized hot spots hundreds of kilometers from Fukushima may well be the tip of the radiological iceberg. He said that more hot spots can be found where rainwater accumulates, like the drainage ditch in Kashiwa, and urged the public to take readings of similar places in their neighborhoods on their own, instead of waiting around for the government's “plodding” surveys. He used side ditches, openings near downspouts and soil under evergreen trees as examples. Fukushi added, contamination in much of Kashiwa is higher than other parts of the Tokyo metropolitan area, so the mini hot spot wasn't a surprise, "If the (cesium) detected was 100 times higher than the amount measured [elsewhere] by the science ministry, then it'd be strange. But in this case, it's just four or five times, so you should not be surprised.” Fukushi further pointed out Kashiwa's residents should not worry about the new hot spot. “The highest radiation reading at the site was 15 microsieverts per hour, which is unlikely to harm anyone because most people will be unlikely to stand around the site for extended periods,” Fukushi said. "Even if a person walked through the site on every day (since March 11), the total exposure dose should not be a cause for fear."
Two more hot spots were discovered more than a month ago and reported today. Both are at schools in Chiba. The first is at Abiko Municipal Daiichi Elementary School where tree roots had worked their way into a drainage ditch, partially blocking flow. The places where the roots penetrated the concrete ditch provided leakage paths into the surrounding soil. The second is at Abiko Municipal Namiki Elementary School, where the area used to bury swimming pool sludge was found to have a higher-than-normal radiation field. Both schools have cordoned off the locations and await instruction on what to do. (Mainichi Shimbun)
TEPCO has posted Plutonium concentrations in the sea-floor off shore from Fukushima Daiichi. Isotopes of the element have been detected, however TEPCO notes, “Detected density of Pu-239 and 240 from September 8 to 25 are within the range of past analyses in the sea around Fukushima Daiichi Nuclear Power Station and Fukushima Daini Nuclear Power Station. Therefore, this cannot be judged to be caused by the nuclear accident of this time.”
TEPCO's most recent posting of airborne radioactivity at the property boundaries of Fukushima Daiichi no longer show detectable Cesium. This good news could be a result of completing the enclosure around reactor building #1, but there is no mention of the possible relation in TEPCO's Press site.
The mayors and other officials from 15 communities that host nuclear power plants met in Tokyo. The main subject of discussion was the possibility if restarting nukes idled since March 11. Some municipalities want restart of reactors to benefit their economies, if their safety is confirmed. But others remained cautious, preventing the association from reaching a consensus. One representative noted the cause of the Fukushima accident has not been confirmed. Another said neither the central government nor power utilities have clarified their policies on the future of nuclear power in Japan. (JAIF)
This year's annual food safety exhibition in Tokyo has a new line of items on display...radiation detection equipment. While the vendors maintain the models can be bought and used in the home, all monitors are clearly industrial-sized. The lowest cost detector is listed at 675,000 yen ($9,000). Demonstrations included having a mock assembly line run packaged food through a detector which could fully scan 5 packages a minute. (NHK World) Clearly, fear of radiation is becoming a lucrative business in Japan.
Citizens' group "Kibo-no-Bokujo -- Fukushima Project" (ranch of hope -- Fukushima project) wants the ~2000 cattle now roaming wild inside the 20km no-go zone to be used for research on the effects of radiation exposure to large mammals. The government has been “culling” the cattle (euthanizing) for months, but the group wants this stopped. They also want to be able to feed and care for the cattle through the upcoming winter.