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"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 government has not disclosed the size of the area contaminated with cesium 137 released from the crippled Fukushima No. 1 plant. Cesium 137 has a long half-life of about 30 years. The Asahi Shimbun calculated the size of the contaminated area based on a distribution map of accumulated cesium 137 levels measured from aircraft, which was released by the science ministry on Sept. 8. "

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, complicating Japan's effort to clean up the disaster-hit region, the government said Tuesday. The survey of 2,200 locations within a 100-km 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 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.

"Cesium that has fallen and been disturbed from the ground surface- 10 times more internal exposure compared to direct inhalation - JAEA Analysis Japan Atomic Energy Agency [JAEA] (Toukai Village, Ibaragi Prefecture) compiled analyses showing that the amount of internal exposure to radioactive cesium from particles that had landed on the ground once and then been disturbed and re-floated was 10 times larger than that of inhaling the airborne particles directly. [This study] will be presented on September 22nd at the Japan Atomic Power Conference that's presently being held in Kitakyushuu City. The JAEA Safety Research Center's research fellow Kimura Masanori (Radiological Protection) points out that "an emphasis needs to be placed to prevent re-floating from the ground surface". Using the survey data of TEPCO and the Ministry of Education, Culture, Sports, Science, and Technology collected in Minamisouma City, Fukushima Prefecture, the amounts of internal exposure to Iodine-131, Cesium-134 and Cesium-137 caused by airborne particles (March 20-May 19) and that of re-floated particles (April 3-June 4) were calculated."

Some of the spent nuclear fuel rods stored in the No. 4 reactor building of the crisis-hit Fukushima Daiichi power plant were confirmed to be damaged, but most of them are believed to be in sound condition, plant operator Tokyo Electric Power Co. said Wednesday. The firm known as TEPCO said its analysis of a 400-milliliter water sample taken Tuesday from the No. 4 unit's spent nuclear fuel pool revealed the damage to some fuel rods in such a pool for the first time, as it detected higher-than-usual levels of radioactive iodine-131, cesium-134 and cesium-137. The No. 4 reactor, halted for a regular inspection before last month's earthquake and tsunami disaster, had all of its 1,331 spent fuel rods and 204 unused fuel rods stored in the pool for the maintenance work and the fuel was feared to have sustained damage from overheating. The cooling period for 548 of the 1,331 rods was shorter than that for others and the volume of decay heat emitted from the fuel in the No. 4 unit pool is larger compared with pools at other reactor buildings. According to TEPCO, radioactive iodine-131 amounting to 220 becquerels per cubic centimeter, cesium-134 of 88 becquerels and cesium-137 of 93 becquerels were detected in the pool water. Those substances are generated by nuclear fission. The government's Nuclear and Industrial Safety Agency said the confirmed radioactive materials were up to 100,000 times higher than normal but that the higher readings may have also been caused by the pouring of rainwater containing much radioactivity or particles of radiation-emitting rubble in the pool.

""The estimated source terms for iodine-131 are very constant, namely 1.3 x 10^17 becquerels per day for the first two days (US station) and 1.2 x 10^17 becquerels per day for the third day (Japan)," the institute said in a German-language statement posted on Wednesday on its website. "For cesium-137 measurements, (the US station) measured 5 x 10^15 becquerels, close, while Japan had much more cesium in its air. On this day, we estimate a source term of about 4 x 10^16." A "becquerel" is the unit that measures how many radioactive nuclei decay per second, and the "source term" refers to the quantity and type of radioactive material released into an environment. "The nuclear catastrophe at Chernobyl had a source term of iodine-131 at 1.76 x 10^18 becquerels of cesium-137 at 8.5 x 10^16 bequerels," the statement added. "The estimated for Fukushima source terms are thus at 20 percent of Chernobyl for iodine, and 20-60 percent of Chernobyl for cesium.""

"High levels of radioactive cesium have been detected in incinerated ashes at waste disposal facilities in Kashiwa, Chiba Prefecture, in apparent effects from the nuclear crisis at the Fukushima Daiichi power plant, the local municipal office said Monday. At one waste disposal center in Kashiwa, up to 70,800 becquerels of radioactive cesium per kilogram were detected from ashes collected on June 24 and more than 60,000 becquerels were observed from ashes collected on July 1 and 2, the city office said. Up to 48,900 becquerels of radioactive cesium were also detected at a facility for burying the ashes from waste disposal centers in the city, while a maximum of 9,780 becquerels were observed at another waste disposal center, the office said. The figures far exceed the 8,000-becquerel per kilogram cap set by the state for waste disposal facilities to temporarily store such ashes. "

"Radioactive cesium far exceeding the legal limit has been detected in hay that was fed to cattle at a farm in Fukushima Prefecture. The prefecture has been investigating why the cattle were contaminated with the radioactive substance. On Sunday, officials took samples of feed and well water at the farm located in Minamisoma City within the planned evacuation zone. They say 75,000 becquerels per kilogram of cesium has been detected in the feed. This far exceeds the government's safety limit of 300 becquerels per kilogram. The farmer says the cattle had been kept inside but were fed with hay left outdoors after the March nuclear accident. Eleven cattle from the farm were sent to Tokyo to be slaughtered. The beef from the animals contained levels of cesium that were more than triple the legal limit. The prefecture has asked farmers in the city to suspend beef cattle shipments. Fukushima Prefecture will continue to investigate the feed and water and check if there were any problems with the way the cattle were raised."

"Fukushima shiitake cesium spikes Kyodo FUKUSHIMA - Radioactive cesium exceeding the designated limit has been detected in shiitake grown in greenhouses at a farm in Soma, Fukushima Prefecture, the prefectural government said. The prefecture said Saturday it has asked the city of Soma and dealers to stop shipment of the mushrooms, and a local agricultural cooperative has begun recalling them after they were found to contain 850 becquerels of cesium per kilogram, exceeding the 500-becquerel limit set by the state. The farm in question has grown the mushrooms on beds made of a mixture of wood chips and nutrients, and the wood chips used in them are suspected to have been contaminated with the radioactive substance, according to the local government. The mushroom beds were sold by the Soma agricultural cooperative. The farm has shipped 1,070 100-gram packages of shiitake since Oct. 24, and they are believed to have been sold at nine supermarkets in the prefecture from Tuesday. No other shiitake produced by the farm have entered the market, it said."

Twenty-three years have passed since The Day of April 26 divided human fates into "before" and "after" the disaster at the Chornobyl Nuclear Power Plant. Until this day it is the world's worst anthropogenic catastrophe unmatched for its environmental impact. For Ukraine Chornobyl is an everyday reality and a host of global-scale problems. Unfortunately, the problems caused by the catastrophe are as acute today as they were 23 years ago. Can one get used to devastated villages and abandoned fertile land? Today nothing prevents us from learning in detail what was happening on the banks of the Prypiat in late April-November 1986. In May 1986 foreigners were the first to learn the truth: on April 30 a Geiger counter on a Swedish nuclear power plant detected an unacceptably high level of radiation. After the Swedish government ascertained that the discharge did not take place in Sweden, it made an official inquiry. Mikhail Gorbachev addressed the people only 18 days after the disaster, on May 14. And three years passed before the information on the radioactivity conditions was declassified and publicized. After the explosion at the Chornobyl Nuclear Power Plant, the scientists at the Institute for Nuclear Research (National Academy of Sciences of Ukraine) identified two groups of radionuclides emitted from the damaged reactor. One of them included volatile radioactive substances carried up high in aerosols with the streams of warm air (iodine-131, iodine-135, cesium-134, cesium-137, and strontium-90). Nearly 30 percent of cesium accumulated in the reactor core was emitted.

" radioactive substance exceeding the state limit has been detected in pasture grass and vegetables in Tochigi and Ibaraki prefectures, neighboring Fukushima Prefecture. 3,480 becquerels of radioactive cesium were detected in one kilogram of pasture grass collected on May 5th in Nikko City, Tochigi Prefecture. The figure exceeds the state limit of 300 becquerels. Also, at two different locations in Nasushiobara City, 3,600 becquerels and 860 becquerels of radioactive cesium respectively were detected in one kilogram of pasture grass collected on May 3rd. Tochigi Prefecture requested farmers in the area where the radioactive substance was detected not to feed pasture grass to livestock. 1,110 becquerels of radioactive cesium were detected in one kilogram of parsley harvested in Ibaraki Prefecture. The figure is more than double the state limit. The parsley had been shipped to a fresh food market in Niigata Prefecture, west of Fukushima. Niigata prefectural government instructed wholesale distributers to stop selling the parsley. Friday, May 13, 2011 05:21 +0900 (JST)"

"The levels of radiation accumulated in soil near the crippled nuclear power plant in northeastern Japan far exceeded the level of radiation the then-Soviet Union had used as a criterion for urging people to evacuate at the time of the 1986 Chernobyl nuclear disaster, threatening to plague local residents for a lengthy period. Using aircraft, the Ministry of Education, Culture, Sports, Science and Technology checked the cesium-137 (half life of about 30 years) and cesium-134 (half life of about two years) accumulated in soil in collaboration with the U.S. Department of Energy in April. Cesium-137 that has longer effects, ranging from 3 million to 14.7 million becquerels per square meter, was detected in Namie, Futaba, Minamisoma, Iitate and Katsurao, northwest of the Fukushima No. 1 Nuclear Power Plant, in Fukushima Prefecture. The levels far exceeded 550,000 bacquerels per square meter, the level the then-Soviet Union had used as a criterion for urging people to evacuate at the time of the 1986 Chernobyl nuclear disaster. Based on recommendations from the International Commission on Radiological Protection (ICRP), the Japanese government used 20 millisieverts per year of radiation in the atmosphere as the criterion to designate evacuation areas in the wake of the nuclear accident in Fukushima. Therefore, there are areas that have not been designated as evacuation zones although they have larger amounts of accumulated radiation. The Ministry of Education, Culture, Sports, Science and Technology says, "Radioactive substances in soil do not enter human bodies immediately." On the other hand, when authorities try to decide whether to allow local residents to return to their homes or resume farming, levels of soil contamination could be one of the hot topics of debate."

"According to Japanese news sources, Japanese whalers tested 6 of 17 whales captured 650 kilometers north-east of the Fukushima nuclear reactor. Of the 6 whales tested 2 were found to contain cesium radiation which must have come from the Fukushima nuclear reactor. The first whale contained 31 becquerels per kilogram of cesium radiation and the second whale and the 24.3 becquerels of radioactive cesium per kilogram. Japan Finds Nuclear Radiation In Whales Caught 650 KM From Fukushima Tokyo - Radioactive caesium was detected from two minke whales caught off a city on the northern Japanese island of Hokkaido, 650 kilometres north-east of a damaged nuclear plant, a news report said on Tuesday. Researchers examined six of the 17 whales during so-called research whaling in Kushiro city, which started this year's season in late April, and they detected 31 becquerels and 24.3 becquerels of radioactive caesium per kilogram in the two whales out of the six, Kyodo News reported citing a whalers' association."

"he National Nuclear Security Administration swept into a Rahway warehouse last week to secure Cesium-137, a radioactive substance, from unused medical equipment. Securing radioactive material is something the administration, part of the Department of Energy, has done about 24,000 times since the late 1990s, but the organization is mounting a new push to encourage hospitals and research facilities to register to have outdated equipment picked up by the government in a timely fashion. The goal is to keep Cesium and other radioactive material under tight security. The agency didn't release any information about the operation until a week later, once the equipment, medical irradiator machines, was treated and safely housed thousands of miles away, west of the Mississippi River. It also did not give the name or address of the Rahway company in order to protect it from those trying to illegally acquire radioactive substances. "

"The National Nuclear Security Administration today announced that it had recovered two "high-activity" sources of cesium-137 from a warehouse 25 miles from New York City. The NNSA removed these "disused and unwanted irradiators" as part of the federal agency's Global Threat Reduction Initiative. Once upon a time, these nuclear sources -- which contained more than 3,000 curies of radioactivity -- were used for medical research. Because of their high radioactivity and "portability," these sealed sources could have been converted into a radiological dispersal device (so-called "dirty bomb"), the NNSA said."

U.S. reactors have generated about 65,000 metric tons of spent fuel, of which 75 percent is stored in pools, according to Nuclear Energy Institute data. Spent fuel rods give off about 1 million rems (10,00Sv) of radiation per hour at a distance of one foot - enough radiation to kill people in a matter of seconds. There are more than 30 million such rods in U.S. spent fuel pools. No other nation has generated this much radioactivity from either nuclear power or nuclear weapons production. Nearly 40 percent of the radioactivity in U.S. spent fuel is cesium-137 (4.5 billion curies) - roughly 20 times more than released from all atmospheric nuclear weapons tests. U.S. spent pools hold about 15-30 times more cesium-137 than the Chernobyl accident released. For instance, the pool at the Vermont Yankee reactor, a BWR Mark I, currently holds nearly three times the amount of spent fuel stored at Dai-Ichi's crippled Unit 4 reactor. The Vermont Yankee reactor also holds about seven percent more rad

The historic discharges at the government's Oak Ridge nuclear facilities have gotten new attention in recent weeks because of the massive release of coal ash that resulted from the pond breach at TVA's Kingston steam plant. One concern was that TVA's cleanup efforts, including the likelhood of dredging, might stir up some of the old radioactive pollution buried under sediments in the Clinch River and points downstream of Oak Ridge. DOE, as noted earlier, is planning to do some additional sampling in the Clinch to supplement the database on pollution levels from previous sampling programs -- mostly since the early 1980s.

Speaking at the annual meeting of the American Geophysical Union (AGU) on Monday, experts revealed a troublesome fact about Chernobyl, the Ukrainian nuclear power plant that blew up in 1986. Recent measurements in the exclusion zone, where no humans can go without protective equipment, have revealed that the radioactive material that was spilled in the area was nowhere near the decay level that was predicted for it. In other words, the scientists are saying that it will take a lot more time for the land to be cleansed than originally believed, Wired reports. Previous estimates, based on the fact that the Cesium 137's half-life is 30 years, estimated that the restriction zone could be lifted, and then re-inhabited soon. But experiments reveal that the radioactive material is not decaying as fast as predicted, and scientists have no clue as to why this is happening. The April 26, 1986 accident was the largest nuclear accident in the world, and only a level 7 event on the International Nuclear Event Scale. Its fallout was made worse by the Soviet Union's attempt at covering up the incident, which saw a lot of people exposed to lethal doses of radiations.

Speaking at the annual meeting of the American Geophysical Union (AGU) on Monday, experts revealed a troublesome fact about Chernobyl, the Ukrainian nuclear power plant that blew up in 1986. Recent measurements in the exclusion zone, where no humans can go without protective equipment, have revealed that the radioactive material that was spilled in the area was nowhere near the decay level that was predicted for it. In other words, the scientists are saying that it will take a lot more time for the land to be cleansed than originally believed, Wired reports. Previous estimates, based on the fact that the Cesium 137's half-life is 30 years, estimated that the restriction zone could be lifted, and then re-inhabited soon. But experiments reveal that the radioactive material is not decaying as fast as predicted, and scientists have no clue as to why this is happening. The April 26, 1986 accident was the largest nuclear accident in the world, and only a level 7 event on the International Nuclear Event Scale. Its fallout was made worse by the Soviet Union's attempt at covering up the incident, which saw a lot of people exposed to lethal doses of radiations.

The Department of Energy is proposing that tons of very low-level radioactive soil from a closed plutonium extraction plant in New York be trucked to Tennessee. The Chestnut Ridge Landfill in Anderson County was the only landfill mentioned as the likely dirt depository during a conference call Thursday organized by DOE. Some 6,000 cubic yards of soil that contains cesium-137 and detectable levels of strontium-90 and plutonium-239/240 are to be excavated from the New York site starting in mid-October, according to a DOE briefing. That's the equivalent of some 200 dump truck loads of waste.

The Department of Energy is proposing that tons of very low-level radioactive soil from a closed plutonium extraction plant in New York be trucked to Tennessee. The Chestnut Ridge Landfill in Anderson County was the only landfill mentioned as the likely dirt depository during a conference call Thursday organized by DOE. Some 6,000 cubic yards of soil that contains cesium-137 and detectable levels of strontium-90 and plutonium-239/240 are to be excavated from the New York site starting in mid-October, according to a DOE briefing. That's the equivalent of some 200 dump truck loads of waste.

For more than a month in the summer of 2006, a metal recycler in Longview, Texas, produced half a million pounds of radioactive material, state and federal documents show. When LeTourneau Inc. workers melted Cesium-137 -- a radioactive material commonly released in nuclear accidents -- the dust containing the radioactive isotope contaminated the workers, along with sections of the facility, according to a July 2006 U.S. Nuclear Regulatory Commission report. No workers suffered direct or immediate harm that could be detected in medical screening. And none of the metal sent to LeTourneau's customers was radioactive, according to the report.

"In a letter dated May 20, the Nuclear Regulatory Commission's Petition Review Board denied a request by Rep. Paul Hodes, D-N.H., that it order Entergy to keep its Vermont Yankee nuclear power plant off-line until a number of actions have been completed regarding a recent leak of contaminants into the groundwater under the site. Hodes had asked the NRC to prevent Yankee from restarting after its current refueling outage until the removal of tritiated water from the ground is completed. He also asked that Entergy finish removing soil that was contaminated with radioactive cesium, manganese, cobalt, zinc and strontium before the plant is restarted. In addition, Hodes requested that the root cause analysis, the final report on why tritium leaked from the plant, and the NRC's review of documents submitted to it are both completed prior to restart. "