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Not to the extent that may cause "chaos" as Professor Kosako predicted, but the prefectural authorities have tested the early harvest and radioactive cesium has been found in Ibaraki and Chiba. The first to find radioactive rice was Ibaraki Prefecture, but the governor vows to fight the "baseless rumor" to promote rice from his prefecture. From Sankei Shinbun (8/19/2011):

As the brown rice grown in Hokota City in Ibaraki Prefecture was found with radioactive cesium, Governor of Ibaraki Masaru Hashimoto answered the reporters on August 19 and said "There is no problem with safety. After the formal testing is complete by the end of August, we will persuade the consumers that there's nothing to worry about consuming Ibaraki rice", and that he will do his best to counter the "baseless rumor".

Governor Hashimoto emphasized safety by saying "It is not the level to worry, even if you eat [the rice] for one whole year". At the same time, he said "Since radioactive cesium has been detected in vegetables, I wouldn't have been surprised to see it detected in rice".

In one location, the contamination level is more than 10 times the Chernobyl level. What a surprise. Now that PM Kan is out, the government dribbles out the information that it withheld as it de-emphasized and even attacked the reports of high soil contamination as measured by private entities including citizens' groups.

The most contaminated location found so far is Okuma-machi, where Fukushima I Nuke Plant is located: 29,460,000 becquerels per square meter with cesium-134 and cesium-137 combined, 15,450,000 becquerels per square meter if only cesium-137 is counted.

The confiscated/closed zone after the Chernobyl accident is set in locations whose cesium-137 level in soil exceeds 1,480,000 becquerels per square meter. The level of cesium-137 in the location in Okuma-machi is 10 times that of the Chernobyl confiscated/closed zone. From Yomiuri Shinbun (3:05AM JST 8/30/2011):

The Ministry of Education and Science (and the media reporting the news) is spinning it as "good news" that radioactive materials detected in river water and well water in Fukushima Prefecture are "far less than the provisional safety limit".If you compare the measured level to the provisional safety limit for water which is high as 200 becquerels/liter for radioactive cesium for adults, well yes, it is far less.If you compare the level to the one before the Fukushima I Nuke Plant accident, it is a different story altogether. The highest strontium-90 level in the Ministry's survey is 5.14 times the highest level measured in 2009, and the highest cesium-137 level is 6,500 times the highest level measured in 2009.The Ministry's announcement (10/20/2011) is here (in Japanese, PDF).

From Asahi Shinbun (10/20/2011):

The Ministry of Education and Science announced the result of the survey of water contamination in rivers and wells in Fukushima Prefecture, except in the 20-kilometer radius from the Fukushima I Nuclear Power Plant. Nuclides such as cesium and strontium were tested, but according to the Ministry there was no detection of radioactive materials exceeding the standard for drinking water.

The highly radioactive dirt in Kashiwa City in Chiba, which measured 57.5 microsieverts/hr 30 centimeters below the surface, was not from radium after all or any other nuclides that are used in industrial or medical use (some suggested cobalt-60, for example). It was from radioactive cesium.On October 22 Kashiwa City announced the result of the analysis of three dirt samples from the location at different depth (one on the surface, two at 30 centimeter deep). The analysis was done on October 22. The unit is becquerels per kilogram:Sample A (surface dirt)Radioactive iodine: NDCesium-134: 70,200Cesium-137: 85,100Total cesium: 155,300

Sample B1 (30 centimeters below the surface)Radioactive iodine: NDCesium-134: 87,000Cesium-137: 105,000Total cesium: 192,000Sample B2 (30 centimeters below the surface)Radioactive iodine: NDCesium-134: 124,000Cesium-137: 152,000Total cesium: 276,000The address of the location is announced by the city as: 柏市根戸字高野台457番3地先. According to the residents, the place is a strip of open space between the residential area and the industrial area, and is used as playground by many residents, young and old.

On receiving the result of the analysis, the Ministry of Education and Science, who had expressed doubt that this high radiation spot in Kashiwa had anything to do with the Fukushima I Nuclear Power Plant accident, now says it cannot deny that it is the result of the accident. The ratio of cesium-134 and cesium-137 is consistent with the radio from the accident.Some speculate that someone in the city cleaned out his house and dumped the resulting radioactive sludge and dirt in this location.What I find it odd is the mismatch of the radiation on the dirt surface, 57.5 microsieverts/hour, and the density of radioactive cesium, maximum 276,000 becquerels/kilogram. The density is too low to account for the extremely high radiation. Cesium alone may not account for the high radiation, but There's no mention in the city's announcement whether it is going to test for other gamma nuclides not to mention alpha and beta.

*Google Translation* Title: Cesium 9,686 Bq / kg soil in Osaka Bay seabed emergency essentials – 1 / 14, strontium-90 detected! Source: http://dub314.blog.fc2.com Date: Jan 14, 2012 Cesium 9,686 Bq / kg soil in Osaka Bay seabed emergency essentials – 1 / 14, strontium-90 detected! - Kind of analysis [core] MAX 9,686Bq/kg

1 / Bay / Osaka grab bottom sampler, December 29 Kansai International Airport near the seabed soil Cesium 134 7,271Bq／Kg Cesium 137 705Bq／Kg Strontium-90 28Bq／Kg 2 / Bay / Osaka grab bottom sampler, December 29 浜寺, seabed soil near the river mouth of the Yamato Cesium 134 8,924Bq／Kg Cesium 137 762Bq／Kg Strontium-90 31Bq／Kg

3 / Bay / Osaka grab bottom sampler, December 29 An Zhichuan estuary to pay near-bottom soil reel Cesium 134 3,527Bq／Kg Cesium 137 269Bq／Kg Strontium-90 ND (not detected) Tsuna / Awaji Cesium 134 2,590Bq／Kg Cesium 137 172Bq／Kg

Have these numbers changed over time? If so by how much? I went to look for TEPCO's handouts in the past. In Reactor 1 SFP, the amount of radioactive cesium increased in 2 months, while in Reactor 3 SFP it has steadily decreased. In Reactor 4 SFP the amount is about the same (here's the May analysis). In Reactor 2 SFP the amount is also about the same. Spent Fuel Pool 1: 6/24/2011: Cesium-134: 12,000 becquerels/cubic centimeters Cesium-137: 14,000 becquerels/cubic centimeters

8/19/2011: Cesium-134: 23,000 becquerels/cubic centimeters Cesium-137: 18,000 becquerels/cubic centimeters

Spent Fuel Pool 3: 5/8/2011: Cesium-134: 140,000 becquerels/cubic centimeters Cesium-137: 150,000 becquerels/cubic centimeters 7/7/2011: Cesium-134: 94,000 becquerels/cubic centimeters Cesium-137: 110,000 becquerels/cubic centimeters

A Wired Magazine article dated December 15, 2009 cites a poster session presentation of the research of the Chernobyl exclusion zone at the American Geophysical Union conference in 2009, and says radioactive cesium may be remaining in the soil far longer than what the half life (30 years) suggests. To note: it was a poster session presentation, and I'm looking to see if it has been formally published in a scientific paper since then.

From Wired Magazine (12/15/2009): SAN FRANCISCO — Chernobyl, the worst nuclear accident in history, created an inadvertent laboratory to study the impacts of radiation — and more than twenty years later, the site still holds surprises.

Reinhabiting the large exclusion zone around the accident site may have to wait longer than expected. Radioactive cesium isn’t disappearing from the environment as quickly as predicted, according to new research presented here Monday at the meeting of the American Geophysical Union. Cesium 137’s half-life — the time it takes for half of a given amount of material to decay — is 30 years. In addition to that, cesium-137’s total ecological half-life — the time for half the cesium to disappear from the local environment through processes such as migration, weathering, and removal by organisms is also typically 30 years or less, but the amount of cesium in soil near Chernobyl isn’t decreasing nearly that fast. And scientists don’t know why.

Six months after the nuclear meltdowns in Fukushima Prefecture, the public's awareness of the threat posed by radiation is entering a new phase: the realization that the biggest danger now and in the future is from contaminated soil.

The iodine-131 ejected into the sky by the Fukushima No. 1 power station disaster was quickly detected in vegetables and tap water — even as far away as Tokyo, 220 km south of the plant. But contamination levels are now so low they are virtually undetectable, thanks to the short half-life of iodine-131 — eight days — and stepped up filtering by water companies.

But cesium is proving to be a tougher foe. The element's various isotopes have half-lives ranging from two to 30 years, generating concern about the food chain in Fukushima Prefecture, a predominantly agricultural region, as the elements wash fallout into the ground. The root of the problem is, well — roots. Cesium-134 and cesium-137 are viewed as potential health threats because vegetables can absorb the isotopes from the soil they're planted in.

Ministry of Education, Culture, Sports, Science and Technology quit measuring plutonium but they mistakenly published the contamination map of Tokyo, Kanagawa and north Kanto area. It was measured by a helicopter. Page 3 Radiation level of Tokyo (1m from the ground) Page 4 Cesium 134+137 on the ground in Tokyo Page 5 Cesium 134 on the ground in Tokyo Page 6 Cesium 137 on the ground in Tokyo Page 7 Radiation level of Kanagawa (1m from the ground)

Page 8 Cesium 134+137 on the ground in Kanagawa Page 9 Cesium 134 on the ground in Kanagawa Page 10 Cesium 137 on the ground in Kanagawa Page 11 Radiation level of north kanto (1m from the ground) Page 12 Cesium 134+137 on the ground in north Kanto Page 13 Cesium 134 on the ground in north Kanto Page 14 Cesium 137 on the ground in north Kanto Overview: Gunma, Tochigi, and north Chiba have hot spots. also, Katsushika, Hachioji, and western part of Tokyo are very contaminated.

Kazue Tazaki is a professor emeritus at Kanazawa University in Ishikawa Prefecture. She took the contaminated soil from Iitate-mura in Fukushima Prefecture where the villagers were required to evacuate, and grew rice using that soil.Rice planting and growing was banned in Iitate-mura this year.Professor Tazaki just harvested the rice, and measured the concentration of cesium-137. The result?From the rice grains: 2,600 becquerels/kgFrom the straw: 2,200 becquerels/kgFrom the roots: 1,500 becquerels/kgSoil contamination: 50,000 becquerels/kgRoughly an equal amount of cesium-134 is to be expected. The transfer rate of cesium-137 in this case was about 0.05.

From Toyama Shinbun, local paper in Ishikawa Prefecture (9/27/2011):

Kazue Tazaki, professor emeritus at Kanazawa University has compiled the result of her experiment of growing rice using the soil from Iitate-mura in Fukushima Prefecture where high radiation levels have been recorded. 2,600 becquerels/kg of radioactive cesium was detected from the harvested rice, more than 5 times the provisional safety limit (500 becquerels/kg) set by the national government. It was prohibited to plant rice in Iitate-mura because of the Fukushima I Nuclear Power Plant accident. The professor's data will be extremely valuable in studying the effect of radiation in the soil on the agricultural crops.

I wrote on Monday November 14 about the paper by the international team of scientists on cesium-137 deposition simulation after the Fukushima I Nuclear Power Plant accident, from March 20 to April 19.In the English paper that I linked, there was a map of cesium-137 deposition simulation in much wider area of Japan, which I showed in the post.But then, in the press release by Nagoya University (one of the scientists is from this university), I realized I should have linked the different map of cesium-137 deposition simulation on land and on the ocean. A whole lot of radioactive materials may have fallen on the ocean, the Pacific Ocean AND the Japan Sea. (Remember, this is a simulation map, not the actual measurement.)

Looking at the map, I don't think I want to eat anything from the Pacific Ocean. Or the Japan Sea. Abalone fishing just started in Iwate Prefecture.By the way, the paper and the researchers were criticized heavily on Twitter a couple of days ago (it still continues) from other researchers in Japan. Their beef was that the researchers of the paper withheld this information from the public when it could have made the difference in determining the government policy or in alerting more people on the possibility of much wider radiation contamination. Instead, the researchers waited for the peer review in the very prestigious scientific venue (the National Academy of Sciences of the United States) to be finished and the paper published. Some say the researchers had the temerity to say in their Nagoya University press release on November 15, "We request that the information in the paper not be used to spread a new set of "baseless rumors" [on the contamination]."

Well, as we have seen, they are not alone. There have been a lot of Japanese researchers who have done what they just did, announcing what could have been the vital information after their papers got accepted by foreign peer-reviewed magazines. I personally know one, whose radiation survey result in locations in Fukushima might have made a significant difference. But the researcher is still sitting on the data (though he was careless enough to put it on his website for a long time), because his paper is being peer-reviewed.But then there are researchers like Professor Yukio Hayakawa of Gunma University, who released the radiation contour map he created soon after the accident, to much ridicule from the establishment initially. And Professor Bin Mori of Tokyo University, who published his world-first discovery of bio-concentration of radioactive silver in spider on his personal blog, and allowed me to spread the information both in Japanese and in English so that more people know about it as soon as possible.

Japan’s six reactor Fukushima Daichi nuclear complex has inadvertently become the world’s bell-weather poster child for the inherent risks of nuclear power ever since the 11 March Tohoku offshore earthquake, measuring 9.0 on the Richter scale, triggered a devastating tsunami that effectively destroyed the complex. Ever since, specialists have wrangled about how damaging the consequences of the earthquake and subsequent tsunami actually were, not only for the facility but the rest of the world. The Fukushima Daichi complex was one of the 25 largest nuclear power stations in the world and the Fukushima I reactor was the first GE designed nuclear plant to be constructed and run entirely by the Tokyo Electric Power Company, or TEPCO.

in the aftermath of the disaster, both TEPCO and the Japanese government were at pains to minimize the disaster’s consequences, hardly surprising given the country’s densely populated regions. But now, an independent study has effectively demolished TEPCO and the Japanese government’s carefully constructed minimalist scenario. Mainichi news agency reported that France’s l’Institut de Radioprotection et de Surete Nucleaire (Institute for Radiological Protection and Nuclear Safety, or IRSN) has issued a recent report stating that the amount of radioactive cesium-137 that entered the Pacific after 11 March was probably nearly 30 times the amount stated by Tokyo Electric Power Co. in May.

According to IRSN, the amount of the radioactive isotope cesium-137 that flowed into the ocean from the Fukushima Daiichi nuclear plant between March 21 and mid-July reached an estimated 27.1 quadrillion becquerels. Why should this matter? Aren’t the Japanese authorities on top of the issue? Cesium-137 can cause burns, acute radiation sickness and even death at sufficient doses. It can contaminate food and water and, if ingested, gets distributed around the body, where it builds up in soft tissues, such as muscles. Over time, it is expelled from the body in urine. And where might tingested cesium-137 come from?

The impacts on the ocean of releases of radionuclides from the Fukushima Dai-ichi nuclear power plants remain unclear. However, information has been made public regarding the concentrations of radioactive isotopes of iodine and cesium in ocean water near the discharge point. These data allow us to draw some basic conclusions about the relative levels of radionuclides released which can be compared to prior ocean studies and be used to address dose consequences as discussed by Garnier-Laplace et al. in this journal.(1) The data show peak ocean discharges in early April, one month after the earthquake and a factor of 1000 decrease in the month following. Interestingly, the concentrations through the end of July remain higher than expected implying continued releases from the reactors or other contaminated sources, such as groundwater or coastal sediments. By July, levels of 137Cs are still more than 10 000 times higher than levels measured in 2010 in the coastal waters off Japan. Although some radionuclides are significantly elevated, dose calculations suggest minimal impact on marine biota or humans due to direct exposure in surrounding ocean waters, though considerations for biological uptake and consumption of seafood are discussed and further study is warranted.

there was no large explosive release of core reactor material, so most of the isotopes reported to have spread thus far via atmospheric fallout are primarily the radioactive gases plus fission products such as cesium, which are volatilized at the high temperatures in the reactor core, or during explosions and fires. However, some nonvolatile activation products and fuel rod materials may have been released when the corrosive brines and acidic waters used to cool the reactors interacted with the ruptured fuel rods, carrying radioactive materials into the ground and ocean. The full magnitude of the release has not been well documented, nor is there data on many of the possible isotopes released, but we do have significant information on the concentration of several isotopes of Cs and I in the ocean near the release point which have been publically available since shortly after the accident started.

We present a comparison of selected data made publicly available from a Japanese company and agencies and compare these to prior published radionuclide concentrations in the oceans. The primary sources included TEPCO (Tokyo Electric Power Company), which reported data in regular press releases(3) and are compiled here (Supporting Information Table S1). These TEPCO data were obtained by initially sampling 500 mL surface ocean water from shore and direct counting on high-purity germanium gamma detectors for 15 min at laboratories at the Fukushima Dai-ni NPPs. They reported initially results for 131I (t1/2 = 8.02 days), 134Cs (t1/2 = 2.065 years) and 137Cs (t1/2 = 30.07 years). Data from MEXT (Ministry of Education, Culture, Sports, Science and Technology—Japan) were also released on a public Web site(4) and are based on similar direct counting methods. In general MEXT data were obtained by sampling 2000 mL seawater and direct counting on high-purity germanium gamma detectors for 1 h in a 2 L Marinelli beaker at laboratories in the Japan Atomic Energy Agency. The detection limit of 137Cs measurements are about 20 000 Bq m–3 for TEPCO data and 10 000 Bq m–3 for MEXT data, respectively. These measurements were conducted based on a guideline described by MEXT.(5) Both sources are considered reliable given the common activity ratios and prior studies and expertise evident by several Japanese groups involved in making these measurements. The purpose of these early monitoring activities was out of concern for immediate health effects, and thus were often reported relative to statutory limits adopted by Japanese authorities, and thus not in concentration units (reported as scaling factors above “normal”). Here we convert values from both sources to radionuclide activity units common to prior ocean studies of fallout in the ocean (Bq m–3) for ease of comparison to previously published data.

Here's the image of the test report by Isotope Research Institute in Yokohama City:Strontium-90: 195 becquerels/kg

From the same sample, cesium-134 and cesium-137 were also detected earlier.Cesium-134: 29,775 becquerels/kgCesium-137: 33,659 becquerels/kgTotal cesium: 63,434 becquerels/kg

Isotope Research Institute didn't start testing for radioactive strontium until August 20, according to the Institute's website. Thus the time lag.At the Institute, it costs 65,000 yen (US$847) (pre-tax) to test one sample for strontium-90 (no separate testing for strontium-89), and it takes one week. No volume discount, the webpage says.The ratio of strontium-90 to cesium-137 in this case is about 0.58%. In comparison, the same ratio from the samples taken in Fukushima Prefecture was between slightly less than 0.1% to 8.2%. In other words, the ratio varies too much to discern any pattern.Yokohama City has said it is testing for strontium in the sample taken from the same apartment rooftop but with much higher cesium density (105,600Bq/kg total cesium). But remember there was no official announcement about this high cesium detection because "the apartment building is a private property", according to the city. We'll see if Yokohama will announce anything about strontium-90.

While readings of radiation in the air have returned to pre-3/11 levels in most areas of Japan — not including areas close to the plant and the so-called hot spots — the contamination of soil, which affects the food chain, could pose a long-term health risk, experts say. Iodine-131, cesium-134 and cesium-137 were released in large quantities by the nuclear plant, and if they are accumulated in the body, they could cause cancer.

Kunikazu Noguchi, lecturer at Nihon University and an often-quoted expert on radiological protection, assures that consumers need not worry too much about any produce on the market, because at present, radiation levels in most vegetables, meat, dairy and other foods, even those from Fukushima Prefecture, are far below the government's safety limits and often undetectable. But for consumers concerned about the few incidents of tainted food slipping through the government checks (such as the beef from cattle that had been fed with tainted straw in Fukushima, which was shipped nationwide in July), or families with small children, Noguchi suggests a simple way to minimize their radiation exposure through food: rinse it.

rinsing the food well before cooking, preferably with hot water, and/or boiling or stewing it, a large portion of radioactive elements can be removed. In his book, published in Japanese in mid-July, "Hoshano Osen kara Kazoku wo Mamoru Tabekata no Anzen Manyuaru" ("The Safety Manual for Protecting Your Family From Radiation Contamination"), Noguchi offers tips on how to prepare food, item by item, so consumers can reduce their radiation intake at home.

An extensive area of more than 8,000 square kilometers has accumulated cesium 137 levels of 30,000 becquerels per square meter or more after the accident at the Fukushima No. 1 nuclear power plant, according to Asahi Shimbun estimates.

The affected area is one-18th of about 145,000 square kilometers contaminated with cesium 137 levels of 37,000 becquerels per square meter or more following the 1986 Chernobyl accident in the former Soviet Union.

The contaminated area includes about 6,000 square kilometers in Fukushima Prefecture, or nearly half of the prefecture. Fukushima Prefecture, the third largest in Japan, covers 13,782 square kilometers.

The Fukushima nuclear disaster released twice as much of a radioactive substance into the atmosphere as Japanese authorities estimated, reaching 40% of the total from Chernobyl, a preliminary report says. The estimate of much higher levels of radioactive cesium-137 comes from a worldwide network of sensors. Study author Andreas Stohl of the Norwegian Institute for Air Research says the Japanese government estimate came only from data in Japan, and that would have missed emissions blown out to sea. The study did not consider health implications of the radiation. Cesium-137 is dangerous because it can last for decades in the environment, releasing cancer-causing radiation.

The long-term effects of the nuclear accident are unclear because of the difficulty of measuring radiation amounts people received. In a telephone interview, Stohl said emission estimates are so imprecise that finding twice the amount of cesium isn’t considered a major difference. He said some previous estimates had been higher than his. The journal Atmospheric Chemistry and Physics posted the report online for comment, but the study has not yet completed a formal review by experts in the field or been accepted for publication.

Last summer, the Japanese government estimated that the March 11 Fukushima accident released 15,000 terabecquerels of cesium. Terabecquerels are a radiation measurement. The new report from Stohl and co-authors estimates about 36,000 terabecquerels through April 20. That’s about 42% of the estimated release from Chernobyl, the report says. An official at the Nuclear and Industrial Safety Agency, the Japanese government branch overseeing such findings, said the agency could not offer any comment on the study because it had not reviewed its contents. It also says about a fifth of the cesium fell on land in Japan, while most of the rest fell into the Pacific Ocean. Only about 2% of the fallout came down on land outside Japan, the report concluded.

France's CEREA has the simulation map of ground deposition of cesium-137 from the Fukushima I Nuclear Power Plant accident on its "Fukushima" page. It not only shows Japan but also the entire northern Pacific Rim, from Russian Siberia to Alaska to the West Coast of the US to the entire US. According to the map, the US, particularly the West Coast and particularly California, may be more contaminated with radioactive cesium than the western half of Japan or Hokkaido. It looks more contaminated than South Korea or China. Canada doesn't look too well either, particularly along the border with US on the western half.

From CEREA's Fukushima page: Atmospheric dispersion of radionuclides from the Fukushima-Daichii nuclear power plant CEREA, joint laboratory École des Ponts ParisTech and EdF R&D Victor Winiarek, Marc Bocquet, Yelva Roustan, Camille Birman, Pierre Tran Map of ground deposition of caesium-137 for the Fukushima-Daichii accident. The simulation was performed with a specific version of the numerical atmospheric chemistry and transport model Polyphemus/Polair3D. The parametrisations used for the transport and physical removal of the radionuclides are described in [1,2,3,4]. The magnitude of the deposition field is uncertain and the simulated values of deposited radionuclides could be significantly different from the actual deposition. In particular, the source term remains uncertain. Therefore, these results should be seen as preliminary and they are likely to be revised as new information become available to better constrain the source term and when radionuclides data can be used to evaluate the model simulation results.

The page also has the animated simulation of cesium-137 dispersion from March 11 to April 6, 2011. If the Japanese think they are the only ones who have the radiation and radioactive fallout from the accident, they are very much mistaken, if the simulation is accurate. (Meteorological institutes and bureaus in Austria, Germany, and Norway all had similar simulation maps.) Radioactive materials spewed out of Fukushima I Nuke Plant went up and away on the jet stream, reaching the other side of the Pacific. When the fallout from explosions (March 14, 15) reached the US West Coast, it came with an unusually heavy rainfall in California.

The apartment building is located in the same Kohoku-ku in Yokohama City where 63,000 becquerels/kg of radioactive cesium was found also from the rooftop of another apartment building, and 42,000 becquerels/kg was found from the dirt around the side drain on the road.It looks like this person had the dirt on the rooftop tested on his own, and posted the test result sheet on his blog.Cesium-134: 49,900 becquerels/kgCesium-137: 55,700 becquerels/kgTotal radioactive cesium: 105,600 becquerels/kg

Meanwhile, this is how the Yokohama City workers (or the contract workers) "cleaned" the highly contaminated (42,000 becquerels/kg cesium) dirt from the side of the road. No protection, no masks, no rubber boots.

Yokohama City Assembly recently voted down the citizens' petition asking the city not to accept radiation-contaminated disaster debris from Tohoku by the majority vote by the DPJ and LDP and Komei Party.The city temporarily halted the dumping of radioactive sludge ashes into the ocean as the citizens' protests were fast and furious once they knew about the scheme, but the mayor in the press conference took pains to emphasize that only thing that had gone amiss was that the city officials under her clearly didn't "explain" well enough to the Yokohama residents living in the area around the final dumping site in Minami Honmoku Pier in advance. "We should have explained better to soothe the fear and anxiety of the residents", she said.

Survey Finds Radiation Over Wide Area in Japan, Wall Street Journal, August 30, 2011:

The first comprehensive survey of soil contamination from the Fukushima Daiichi nuclear plant showed that 33 locations spread over a wide area have been contaminated with long-lasting radioactive cesium, the government said Tuesday. The survey of 2,200 locations within a 100-kilometer (62-mile) radius of the crippled plant found that those 33 locations had cesium-137 in excess of 1.48 million becquerels per square meter, the level set by the Soviet Union for forced resettlement after the 1986 Chernobyl disaster. Another 132 locations had a combined amount of cesium 137/134 over 555,000 becquerels per square meter, the level at which the Soviet authorities called for voluntary evacuation and imposed a ban on farming. [...] the latest data point to the possibility that cesium could also be washing away and spreading to other areas, potentially contaminating rivers, lower-lying land and the ocean. [...]