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Workers who relocated the material fell ill simply from inhaling the fumes, Carpenter said. Department of Energy officials said none of the material has leaked outside the outer steel wall or the concrete casing that surrounds the structure, and there is no present hazard to workers or groundwater. They said they were trying to determine whether the material leaked from the inner tank or oozed from a nearby pit into the space between the two walls, known as the annulus. "There's no evidence of it leaking the liquid from the inner shell right now," Gamache said. The material – a mound 2 feet by 3 feet by 8 inches -- is dry and doesn't appear to be growing. It was discovered during a routine video inspection of the annulus conducted last month from a viewpoint not normally used. The possibility that it could have come as overflow from a nearby pit arises because a pipe runs into the annulus from the pit, Gamache said.

But Carpenter, who has talked extensively with workers at Hanford and was briefed Tuesday by one of the Department of Energy's senior officials at the tank farm, said he believed the evidence was strong that there was a leak. "I know Hanford would like it not to be so. But the people I'm talking to at the Hanford site say, no, it really does look like a leak," he said.

"From what I'm being told and looking at the pictures, it appears it's coming from under the tank and going up. Which is a far cry from it coming from the pit." Gamache said an initial sample of the material revealed that "the contamination levels were higher than expected" and it definitely contained radioactive waste. "There wasn't enough material to fully characterize the material, so we're preparing to pull another sample. That will probably happen around the mid-September time frame," she said. Carpenter said that if the inner tank leaked, it would probably prompt the need to reevaluate expectations that the tanks could safely act as interim storage vessels for several decades.

Plutonium belongs to the class of elements called transuranic elements whose atomic number is higher than 92, the atomic number of uranium. Essentially all transuranic materials in existence are manmade. The atomic number of plutonium is 94. Plutonium has 15 isotopes with mass numbers ranging from 232 to 246. Isotopes of the same element have the same number of protons in their nuclei but differ by the number of neutrons. Since the chemical characteristics of an element are governed by the number of protons in the nucleus, which equals the number of electrons when the atom is electrically neutral (the usual elemental form at room temperature), all isotopes have nearly the same chemical characteristics. This means that in most cases it is very difficult to separate isotopes from each other by chemical techniques.

Plutonium-239 and plutonium-241 are fissile materials. This means that they can be split by both slow (ideally zero-energy) and fast neutrons into two new nuclei (with the concomitant release of energy) and more neutrons. Each fission of plutonium-239 resulting from a slow neutron absorption results in the production of a little more than two neutrons on the average. If at least one of these neutrons, on average, splits another plutonium nucleus, a sustained chain reaction is achieved.

The even isotopes, plutonium-238, -240, and -242 are not fissile but yet are fissionable–that is, they can only be split by high energy neutrons. Generally, fissionable but non-fissile isotopes cannot sustain chain reactions; plutonium-240 is an exception to that rule. The minimum amount of material necessary to sustain a chain reaction is called the critical mass. A supercritical mass is bigger than a critical mass, and is capable of achieving a growing chain reaction where the amount of energy released increases with time.

The amount of material necessary to achieve a critical mass depends on the geometry and the density of the material, among other factors. The critical mass of a bare sphere of plutonium-239 metal is about 10 kilograms. It can be considerably lowered in various ways. The amount of plutonium used in fission weapons is in the 3 to 5 kilograms range. According to a recent Natural Resources Defense Council report (1), nuclear weapons with a destructive power of 1 kiloton can be built with as little as 1 kilogram of weapon grade plutonium(2). The smallest theoretical critical mass of plutonium-239 is only a few hundred grams.

In contrast to nuclear weapons, nuclear reactors are designed to release energy in a sustained fashion over a long period of time. This means that the chain reaction must be controlled–that is, the number of neutrons produced needs to equal the number of neutrons absorbed. This balance is achieved by ensuring that each fission produces exactly one other fission. All isotopes of plutonium are radioactive, but they have widely varying half-lives. The half-life is the time it takes for half the atoms of an element to decay. For instance, plutonium-239 has a half-life of 24, 110 years while plutonium-241 has a half-life of 14.4 years. The various isotopes also have different principal decay modes. The isotopes present in commercial or military plutonium-239 are plutonium-240, -241, and -242. Table 2 shows a summary of the radiological properties of five plutonium isotopes. The isotopes of plutonium that are relevant to the nuclear and commercial industries decay by the emission of alpha particles, beta particles, or spontaneous fission. Gamma radiation, which is penetrating electromagnetic radiation, is often associated with alpha and beta decays.

Table 3 describes the chemical properties of plutonium in air. These properties are important because they affect the safety of storage and of operation during processing of plutonium. The oxidation of plutonium represents a health hazard since the resulting stable compound, plutonium dioxide is in particulate form that can be easily inhaled. It tends to stay in the lungs for long periods, and is also transported to other parts of the body. Ingestion of plutonium is considerably less dangerous since very little is absorbed while the rest passes through the digestive system.

Plutonium-239 is formed in both civilian and military reactors from uranium-238. The subsequent absorption of a neutron by plutonium-239 results in the formation of plutonium-240. Absorption of another neutron by plutonium-240 yields plutonium-241. The higher isotopes are formed in the same way. Since plutonium-239 is the first in a string of plutonium isotopes created from uranium-238 in a reactor, the longer a sample of uranium-238 is irradiated, the greater the percentage of heavier isotopes. Plutonium must be chemically separated from the fission products and remaining uranium in the irradiated reactor fuel. This chemical separation is called reprocessing. Fuel in power reactors is irradiated for longer periods at higher power levels, called high “burn-up”, because it is fuel irradiation that generates the heat required for power production. If the goal is production of plutonium for military purposes then the “burn-up” is kept low so that the plutonium-239 produced is as pure as possible, that is, the formationo of the higher isotopes, particularly plutonium-240, is kept to a minimum. Plutonium has been classified into grades by the US DOE (Department of Energy) as shown in Table 5.

It is important to remember that this classification of plutonium according to grades is somewhat arbitrary. For example, although “fuel grade” and “reactor grade” are less suitable as weapons material than “weapon grade” plutonium, they can also be made into a nuclear weapon, although the yields are less predictable because of unwanted neutrons from spontaneous fission. The ability of countries to build nuclear arsenals from reactor grade plutonium is not just a theoretical construct. It is a proven fact. During a June 27, 1994 press conference, Secretary of Energy Hazel O’Leary revealed that in 1962 the United States conducted a successful test with “reactor grade” plutonium. All grades of plutonium can be used as weapons of radiological warfare which involve weapons that disperse radioactivity without a nuclear explosion.

Benedict, Manson, Thomas Pigford, and Hans Wolfgang Levi, Nuclear Chemical Engineering, 2d ed. (New York: McGraw Hill Book Company, 1981). Wick, OJ, Editor, Plutonium Handbook: A Guide to the Technology, vol I and II, (La Grange Park, Illinois: American Nuclear Society, 1980). Cochran, Thomas B., William M. Arkin, and Milton M. Honig, Nuclear Weapons Databook, Vol I, Natural Resources Defense Council. (Cambridge, Massachusetts: Ballinger Publishing Company, 1984) Plutonium(IV) oxide is the chemical compound with the formula PuO2. This high melting point solid is a principal compound of plutonium. It can vary in color from yellow to olive green, depending on the particle size, temperature and method of production.[1]

The leakage very likely isn’t over, either. The Tokyo Electric Power Company, the operator of the plant, said Sept. 20 that it believed that something on the order of 200 to 500 tons a day of groundwater might still be pouring into the damaged reactor and turbine buildings.Ken Buesseler, a scientist at the Woods Hole Oceanographic Institution, who in 1986 studied the effects of the Chernobyl disaster on the Black Sea, said the Fukushima disaster appeared to be by far the largest accidental release of radioactive material into the sea.

Chernobyl-induced radiation in the Black Sea peaked in 1986 at about 1,000 becquerels per cubic meter, he said in an interview at his office in Woods Hole, Mass. By contrast, the radiation level off the coast near the Fukushima Daiichi plant peaked at more than 100,000 becquerels per cubic meter in early April.

Working with a team of scientists from other institutions, including the University of Tokyo and Columbia University, Mr. Buesseler’s Woods Hole group in June spent 15 days in the waters off northeast Japan, studying the levels and dispersion of radioactive substances there and the effect on marine life.The project, financed primarily by the Moore Foundation after governments declined to participate, continued to receive samples from Japanese cruises into July.

While Mr. Buesseler declined to provide details of the findings before analysis is complete and published, he said the broad results were sobering.“When we saw the numbers — hundreds of millions of becquerels — we knew this was the largest delivery of radiation into the ocean ever seen,’’ he said. ‘‘We still don’t know how much was released.’’Mr. Buesseler took samples of about five gallons, filtered out the naturally occurring materials and the materials from nuclear weapon explosions, and measured what was left.

The scientists had expected to find ocean radiation levels falling off sharply after a few months, as radioactive substances were dispersed by the currents, because, he said, “The ocean’s solution to pollution is dilution.’’The good news is that researchers found the entire region 20 to 400 miles offshore had radiation levels too low to be an immediate threat to humans.But there was also an unpleasant surprise. “Rather than leveling off toward zero, it remained elevated in late July,’’ he said, up to about 10,000 becquerel per cubic meter. ‘‘That suggests the release problem has not been solved yet.”

The working hypothesis is that contaminated sediments and groundwater near the coast are continuing to contaminate the seas, he said.The international team also collected plankton samples and small fish for study. Mr. Buesseler said there were grounds for concern about bioaccumulation of radioactive isotopes in the food chain, particularly in seaweed and some shellfish close to the plants. A fuller understanding of the effect on fish that are commercially harvested will probably take several years of data following several feeding cycles, he said.

‘We also don’t know concentrations in sediments, so benthic biota may be getting higher doses and if consumed (shellfish), could be of concern,’’ he wrote later in an e-mail, referring to organisms that dwell on the sea floor.The study also found that the highest cesium values were not necessarily from the samples collected closest to Fukushima, he said, because eddies in the ocean currents keep the material from being diluted in some spots farther offshore.The overall results were consistent with those previously found by Japanese scientists, Mr. Buesseler said.He said more research was urgently needed to answer several questions, including why the level of contamination offshore near the plant was so high.“Japan is leading the studies, but more work is needed than any one country, or any one lab, can possibly carry out,” he said.

Gunma and Tochigi prefectures have a combined 3,800 square kilometers with an annual exposure of 1 millisievert or more. Among Tokyo's 23 wards, Katsushika Ward had the highest radiation level of 0.33 microsievert per hour, according to a science ministry map showing radioactive contamination for 12 prefectures. The ward government has been measuring radiation levels in seven locations once a week since late May. It plans to take measurements at about 500 public facilities, such as schools and parks, in response to residents' demands for detailed surveys.

The Gunma prefectural government has measured radiation levels in 149 locations since September and has identified six northern mountainous municipalities with an annual exposure of 1 millisievert or more. Earlier this month, the prefectural government asked 35 municipalities to decide whether radioactive materials will be removed. High radiation levels were detected in Minakami, Gunma Prefecture, known as a hot spring resort. Mayor Yoshimasa Kishi said the town could be mistaken as a risky place if it decides to have radioactive materials removed. The science ministry's map showed that 0.2 to 0.5 microsievert was detected in some locations in Niigata Prefecture. Niigata Governor Hirohiko Izumida said the figures were likely mistaken, noting that these locations have high natural radiation levels because of granite containing radioactive materials.

The prefectural government plans to conduct its own surveys of airborne radiation levels and soil contamination. Many municipalities are calling for financial support for removing radioactive materials. In Kashiwa and five other cities in northern Chiba Prefecture, radioactive materials need to be removed over an estimated 180 square kilometers of mainly residential areas. The Kashiwa city government is providing up to 200,000 yen ($2,620) to kindergartens and nursery schools for removal work. But some facilities have asked children's parents to help pay the costs because they cannot be covered by the municipal assistance.

The Ministry did the survey twice in June and August. It selected the survey locations from the areas that showed relatively high level of cesium deposition in soil in the Ministry's aerial survey after the accident. 50 river locations and 51 wells were selected. Radioactive cesium and iodine-131 were measured in all 101 locations. Strontium and plutonium were measured in 10 river locations where the air radiation was high. Similarly, at 6 wells, only strontium was measured.

The highest cesium-137 (half life 30 years) for the river water was detected in Mano District in Minami Soma City (37 kilometers north by northwest from the nuke plant), at 2.0 becquerels/kg. The average amount of cesium-137 in river water was 0.58 becquerels/kg. The highest cesium-137 for the well water was detected in Nukazawa in Motomiya City (54 kilometers west of the plant), at 1.1 becquerels/kg. The average for well water was 0.49 becquerels/kg.

According to the Ministry of Education and Science, "Radioactive materials in both river water and well water are far below the provisional safety limit of 200 becquerels/kg". However, according to the Ministry's national survey in 2009, the highest level in river water was found in Akita Prefecture at 0.00037 becquerels/kg (ND in Fukushima). So, 2.0 becquerels/kg of cesium-137 detected this time in Fukushima is 5,400 times as much as the highest level in 2009 in river water. As to 1.1 becquerels/kg of cesium-137 from the well water, it is 6,500 times as much as the highest level detected in tap water in 2009.

The largest amount of strontium-90 (half life 30 years) was detected in a river in Onahama in Iwaki City, at 0.018 becquerels/kg, 5.14 times the level detected in the 2009 survey. Strontium-90 in well water was the same level as before the accident. Plutonium and iodine-131 were below the detection limit.

According to the Ministry's calculation on the internal radiation if one drinks the river water that had the maximum amount of radioactive materials for one year, cesium-137 would result in 0.025 millisievert, and strontium-90 in 0.00049 millisievert.Hmmm. They tested an alpha emitter (plutonium) and a beta emitter (strontium) in water in locations with high air radiation? What does high air radiation have to do with alpha and beta emitters? And what about other nuclides, like cobalt-60?The Ministry of Education tested water at these locations twice: first in late June to early July, then in early August. Looking at the result, there are two locations where the amount of radioactive cesium significantly INCREASED during the one month, indicating perhaps the inflow of radioactive materials from the surrounding mountains.The Ministry's document has very poor resolution, but here's the page that shows charts of cesium-137 detections (page 19 in the document):

Firstly, 'spent fuel' is defined as fuel whose elements have been removed from the reactor because the fissionable material they contain has been depleted to a level near where it can no longer sustain a chain reaction. The high concentration of radioactive fission products in spent power-reactor fuel creates a gamma-radiation field, which at a distance of a metre would be lethal. South Africa, or more accurately Necsa, no longer has any use for this material.

Secondly, the US and South Africa have been working constructively for a number of years on various peaceful use applications of nuclear material and in particular on the need to minimise the use of HEU. Examples of such co-operation are the conversion of South Africa's SAFARI-1 reactor to low enriched uranium (LEU) fuel as well as training in medical responses to nuclear and radiological emergencies. Indeed, today South Africa is leading the transition to produce the medical isotope molybdenum-99 (Mo-99) with LEU rather than HEU.

Zuma was one of only five African Heads of State or government invited to develop concrete measures towards ensuring that nuclear materials under their control are not stolen or diverted (the others being Algeria, Egypt, Morocco and Nigeria). They pledged to improve security as changing conditions may require, and to exchange best practices and practical solutions for doing so. The Summit's final communiqué also highlighted the fact that 'highly enriched uranium and separated plutonium require special precautions'.

Thirdly, the return is not unique. The repatriation of used and unused HEU fuel to its country of origin - either the US or Russia - has been an international goal since the early 1980s. Some 1,249kg of US-origin highly enriched uranium from sites around the world have already been returned, including from Chile in April 2010 just after the earthquake the previous February.

Finally, and perhaps most importantly, the spent fuel storage facility at Necsa is not, and has never been, 'vulnerable' - in the sense of being in danger of being accessed by organisations or persons with criminal intent or worse, with terrorist ideologies.

As for green tea, the tea producer was mixing the tea that passed the provisional safety limit but which still contained radioactive cesium with the tea made in Kyushu, far away from Fukushima I Nuke Plant. The blend was the radioactive tea 20%, the Kyushu tea 80%.Most water purification plants had voluntarily stopped shipping the radioactive sludge until the provisional safety limit was decided. However, the company who runs this particular water purification plant that continued to ship says, "The detection level was low. If the sludge was made into the garden soil it would be diluted further". The company blames the manufacturers who bought the radioactive sludge, saying "The ultimate responsibility rests with those who make [the sludge] into final products and sell them". The company is currently selling the radioactive sludge to the businesses that supply dirt for construction projects, as the national government has sent out an instruction that "the use of radioactive sludge in the garden soil had better be suspended".According to the green tea producer, there weren't enough of the tea leaves that passed the safety limit [but still contained radioactive cesium] to make it worthwhile to sell, so the company decided to mix it to make a "blend tea". The person in charge of the "blend tea" says "We made it clear in the package that it was a "blend tea", so there should be no problem. We just wanted to make the tea safer for the consumers".

SuspicionThese practices are not illegal, and when the contaminated products are mixed with non-contaminated products there should be less ill-effect on humans. However, if this "dilute and sell" model takes hold, it will only add to doubt and confusion for the consumers. Damage from "baseless rumors" may spread to milk and rice. It has been a standard practice to mix milk from different locations. The same goes for rice.The national consumer association federation chief proposes the detailed labeling of the place of manufacture on a prefectural level so that the consumers can choose safely.

However, there is no law requiring the place of manufacture for the garden soil, and there is no voluntary guideline by the industry either. The national standard for food labeling only requires the label "Made in Japan" in the case of "blended" produce like rice and tea and processed foods; there is no requirement to show the name of prefecture where the product is made. The Consumer Affairs Agency of Japan [which is supposed to regulate the industries with the welfare of consumers in mind] is not going to do anything at this point, saying "Places of manufacture for the blended goods may change, so it is not practical to require detailed labels".

On the other hand, the head of the Worldwide Agricultural Policy Information Center is critical. He says "The role of the national government is to stop the spread of radioactive materials. To allow goods with radioactive materials to be diluted and and sold widely would be considered as approval by the national government to spread the contamination [all over Japan]". JA agricultural co-op Fukushima is also distrustful of the government policy [or lack thereof], saying "There will be no "baseless rumors" if the produce that is found with radioactive materials is not sold".However, for now, we can only count on the voluntary effort by the industries. A new national policy would be necessary, just like when there was a problem of labeling "made in Japan" and "imported" goods.

The government and plant operator TEPCO are trumpeting the operation of the circulation cooling system, as if it marks a successful resolution to the disaster. However, radiation continues to leak from the reactors. The longer the circulation cooling system keeps running, the more radioactive waste it will accumulate. It isn't really leading us in the direction we need to go.

It's doubtful that there's even a need to keep pouring water into the No.1 reactor, where nuclear fuel is suspected to have burned through the pressure vessel. Meanwhile, it is necessary to keep cooling the No. 2 and 3 reactors, which are believed to still contain some fuel, but the cooling system itself is unstable. If the fuel were to become overheated again and melt, coming into contact with water and trigger a steam explosion, more radioactive materials will be released.

TEPCO says it is aiming to bring the No. 1, 2 and 3 reactors to cold shutdown by January 2012. Cold shutdown, however, entails bringing the temperature of sound nuclear fuel in pressure vessels below 100 degrees Celsius. It would be one thing to aim for this in April, when the government had yet to confirm that a meltdown had indeed taken place. But what is the point of "aiming for cold shutdown" now, when we know that fuel is no longer sound?

In the days ahead, the storage of enormous quantities of radiation-contaminated waste, including tainted mud resulting from the decontamination process, will become a major problem.

When the Three Mile Island accident took place in 1972, the melted nuclear fuel had stayed within the pressure vessel, making defueling possible. With Fukushima, however, there is a possibility that nuclear fuel has fallen into the ground, in which case it will take 10 or 20 years to recover it. We are now head to head with a situation that mankind has never faced before.

TEPCO intentionally dumped radioactive materials into the ocean, as they had no additional room for storage, the levels showed no signs of decreasing, and all desalination hopes were falling woefully short.  It would also be found that many leaks around, and inside of the reactors were also finding their way into the Pacific, but the public was told that there would not be any risk to them, or the living creatures in the sea. After 7 months however, impact can be found all over the island nation, and spreading throughout the ocean, despite the expectations it would merely be diluted exponentially. In September, scientists from the government's Meteorological Research Institute and the Central Research Institute of the Electric Power Industry announced their findings at a meeting of the Geochemical Society of Japan, adding that some of the cesium will also flow into the Indian Ocean and, eventually, reach the Atlantic.

Floating Radioactive Debris Reaching Hawaii Sooner Than Expected The researchers believed that the cesium had initially dispersed into the Pacific from the coast of Fukushima Prefecture but would be taken to the southwest by the prevailing currents at a depth of around 1,300 feet. Researchers thought it would take years to reach the islands. But now, according to a University of Hawaii researchers, the debris will arrive sooner than expected.  ....Since the March 11th earthquake and tsunami, researchers have been predicting it would take about two years for the debris from Japan to hit Hawaii's west-facing beaches. “We have a rough estimate of 5 to 20 million tons of debris coming from Japan,” said UH computer programming researcher Jan Hafner.

..Their path back to Russia crossed exactly across the projected field of the debris.  Soon after passing the Midway Islands on Sept. 22, they hit the edge of the tsunami debris.   “They saw some pieces of furniture, some appliances, anything that can float, and they picked up a fishing boat,” said Hafner.  It was a 20-foot fishing boat with the word "Fukushima" on it.  “That's actually our first confirmed report of tsunami debris,” said Hafner...  Source: kitv.com 

The Public Concern Was Never Really An 'Official' concern In the first few days after the March 11 earthquake and tsunami that damaged the Fukushima Daiichi power plant, government authorities and the company were criticized for not providing information in a timely fashion. A Kyodo News survey released Sunday found that 58% of respondents did not approve of the government's handling of the crisis at the nuclear plant. More than two weeks later, updates provided via news conferences, press releases, data charts and Twitter feeds have become very frequent and very technical. To a lay person, the onslaught of numbers and unfamiliar terms can feel indecipherable.

Initially reports had quieted concerns by stating that the materials would be diluted so vastly that the radioactivity would not be able to accumulate, and would not affect the environment.  The experts claimed they would track the deposition and floating radioactive debris field making its way on a trans-Pacific trip to the United States. Apparently, the experts in Japan didn't get the message.  The Japanese regularly tested the seawater only for 'popular' Iodine and Cesium isotopes instead of all known fission-produced radioactive materials, for the first 3 months after the disaster.  By March 31st, radioactive contamination concentration was 4,385 times the legal limit, up from 3,355 times on Tuesday, according to Kyodo. In response, the government had pledged to increase radiation monitoring on land and by sea and to consider increasing the evacuation zone — however time has shown little action would follow these vows.

This ruse would only work, if the officials could hold off on monitoring and tracking the deposition as long as possible, until the plume had finally moved away from the coastline. TEPCO had intentionally dumped over 11 tons of water in the first few weeks, all of which contained high concentrations of radioactive materials. There would be further reports that would be difficult to quantify, including unknown amount of contaminated water leaked into the ocean from a damaged reservoir, and a plethora of uncharted and un-monitored leaks from the reactors. After dealing with the spring, the tsunami season arrived and even more contamination entered the sea through fallout from the air, and through precipitation runoff.

By March 26th, the news broke that levels near the reactor were 1,250 times the legal limits, as the levels of I-131 reported just a few hundred meters offshore boomed to ten times the already increased levels in a matter of days.  Tepco also reported levels of caesium-137 - which has a longer half life of about 30 years - almost 80 times the legal maximum. Findings throughout the summer challenged experts and officials however, as radiation levels found contamination in some parts had risen over 3,000 times the normal levels. "This is a relatively high level," nuclear safety agency official Hidehiko Nishiyama said in a televised news conference. Drinking 500ml of fresh water with the same concentration would expose a person to their annual safe dose, Mr Nishiyama said, but he ruled out an immediate threat to aquatic life and seafood safety.

"Generally speaking, radioactive material released into the sea will spread due to tides, so you need much more for seaweed and sea life to absorb it," Mr Nishiyama said. Pledges to Monitor and Track Contamination Left Unattended Japanese officials said they would check the seawater about 20 miles (30km) off the coast for radiation back in March, yet even though finding contamination, resumed testing withing 20 km, and downplayed the effects by stating they expected it to show there is no need to be concerned about any possible effect to fish.

By the time that current reaches the Central Pacific, there are branches heading more towards Alaska and the South—that gets harder to predict,” said Ken Buesseler, a senior scientist with the Woods Hole Oceanographic Institute told Jeff McMahon, a reporter for Forbes. “But that’s one of the things that several people hope to do by measuring these isotopes even at levels when they’re not harmful. We could actually track those ocean currents and better understand the circulation pattern in the Pacific.” Japanese Science and Fisheries Agencies Late Decision to Expand Testing On Marine Products to Weekly Testing 20-30 km Around Fukushima Daiichi

The science ministry and the Fisheries Agency will strengthen testing on marine products and widen the survey for seawater for radiation contamination from the damaged Fukushima No.1 nuclear power plant. The tests on marine products will be conducted once a week, in principle, depending on the size of the fish hauls, in Fukushima, Miyagi and Ibaraki prefectures. The government eased restrictions on land use outside the 20-kilometer no-entry zone around the plant in September. It will now test waters 20-30 km from the plant for radiation, and eventually survey seawater beyond 280 km from the coast using more accurate instruments, officials said.

Sources: ajw.asahi.com, via Nuclear News | What The Physics? Forbes.com SkyNews TEPCO IAEA

"We cannot associate low levels of Strontium-90 in fish in the Connecticut River with Vermont Yankee-related radioactive materials without other supporting evidence," the report said. MORE ANALYSIS NEEDED The Health Department asked for additional analysis on the fish obtained on June 9, 2010 that contained the strontium-90 and also on other fish samples. These analyses will take weeks to complete, the Health Department said, noting it is working to obtain additional fish for testing much farther upstream in the Connecticut River. The Connecticut River divides Vermont and New Hampshire before running through Massachusetts and Connecticut. Vermont Yankee is located in Vernon, Vermont, near the border between Vermont, New Hampshire and Massachusetts about 110 miles northwest of Boston.

Strontium-90 and other human made radioactive materials come from the fairly constant release of very low quantities from medical and industrial users of radioactive materials, and from infrequent releases such as above-ground nuclear weapons testing in the 1950s, and the nuclear reactor accidents at Chernobyl in 1986 and Fukushima in 2011. Radioactive materials are nothing new for Vermont Yankee. In January 2010, Entergy said it discovered a radioactive tritium leak at the plant. The company stopped that leak in March 2010 but not before the state Senate, which was then led by now Governor Shumlin, voted to block the state from allowing the plant to run beyond March 2012.

Yo:  So making comparisons with X-rays and CT scans has no meaning.  Because you can breathe in radioactive material. Hirose:  That’s right.  When it enters your body, there’s no telling where it will go.  The biggest danger is women, especially pregnant women, and little children.  Now they’re talking about iodine and cesium, but that’s only part of it, they’re not using the proper detection instruments.  What they call monitoring means only measuring the amount of radiation in the air.  Their instruments don’t eat.  What they measure has no connection with the amount of radioactive material. . .

Read the report here.

The Kan Administration set up a fact-finding commission in late May to figure out what went wrong at Fukushima I Nuclear Power Plant that led to the catastrophic accident, even if the accident is still ongoing as of August.The Kan Administration set up a fact-finding commission in late May to figure out what went wrong at Fukushima I Nuclear Power Plant that led to the catastrophic accident, even if the accident is still ongoing as of August. There were many critics who said "First thing first", which was to stop the emission of radioactive materials from the broken reactors and do whatever possible to reduce the amount of the contaminated water, and .. (list is endless). But the government, who is always eager to paint a positive picture that everything is according to schedule and going well, wanted the commission to "investigate" the accident to learn from the mistakes.There were many critics who said "First thing first", which was to stop the emission of radioactive materials from the broken reactors and do whatever possible to reduce the amount of the contaminated water, and .. (list is endless). But the government, who is always eager to paint a positive picture that everything is according to schedule and going well, wanted the commission to "investigate" the accident to learn from the mistakes.

TEPCO was preoccupied with the condition of the reactor and the Containment Vessel, and didn't think of the risk of hydrogen explosion. "There was no one who could have predicted the explosion.

The Kan Administration set up a fact-finding commission in late May to figure out what went wrong at Fukushima I Nuclear Power Plant that led to the catastrophic accident, even if the accident is still ongoing as of August.

There were many critics who said "First thing first", which was to stop the emission of radioactive materials from the broken reactors and do whatever possible to reduce the amount of the contaminated water, and .. (list is endless). But the government, who is always eager to paint a positive picture that everything is according to schedule and going well, wanted the commission to "investigate" the accident to learn from the mistakes.

What better way to give the impression that the accident is over, than to form a commission to investigate the accident?

Still, the commission led by a Tokyo University professor (emeritus) and including 3 attorneys (one of them a UN committee member fighting for equal rights for women) and one novelist, has been interviewing (or "interrogating" is the word used in the Japanese press) TEPCO managers at Fukushima I Nuke Plant, and part of their findings have apparently been leaked to Mainichi Shinbun. The commission meetings are not open to the public.

From Mainichi Shinbun (2:31AM JST 8/17/2011), what TEPCO managers at the plant is saying:

About the explosion of Reactor 1 building at 3:36PM on March 12:

There was no manual for the vent operation. They figured out the procedure by studying the blueprint

TEPCO was preoccupied with the condition of the reactor and the Containment Vessel, and didn't think of the risk of hydrogen explosion. "There was no one who could have predicted the explosion.

EPCO was preoccupied with the condition of the reactor and the Containment Vessel, and didn't think of the risk of hydrogen explosion. "There was no one who could have predicted the explosion.

TEPCO was preoccupied with the condition of the reactor and the Containment Vessel, and didn't think of the risk of hydrogen explosion. "There was no one who could have predicted the explosion.""

he Fukushima disaster has been rated as a "level seven" on the International Nuclear and Radiological Event Scale (INES). This level, the highest, is the same as the Chernobyl nuclear disaster in 1986, and is defined by the scale as: "[A] major release of radioactive material with widespread health and environmental effects requiring implementation of planned and extended countermeasures."The Fukushima and Chernobyl disasters are the only nuclear accidents to have been rated level seven on the scale, which is intended to be logarithmic, similar to the scale used to describe the comparative magnitude of earthquakes. Each increasing level represents an accident approximately ten times more severe than the previous level.

Doctors in Japan are already treating patients suffering health effects they attribute to radiation from the ongoing nuclear disaster."We have begun to see increased nosebleeds, stubborn cases of diarrhoea, and flu-like symptoms in children," Dr Yuko Yanagisawa, a physician at Funabashi Futawa Hospital in Chiba Prefecture, told Al Jazeera.

r Helen Caldicott, the founding president of Physicians for Social Responsibility, a group that was awarded the Nobel Peace Prize in 1985, is equally concerned about the health effects from Japan's nuclear disaster."Radioactive elements get into the testicles and ovaries, and these cause genetic disease like diabetes, cystic fibrosis, and mental retardation," she told Al Jazeera. "There are 2,600 of these diseases that get into our genes and are passed from generation to generation, forever."

Al Jazeera's Aela Callan, reporting from Japan's Ibaraki prefecture, said of the recently detected high radiation readings: "It is now looking more likely that this area has been this radioactive since the earthquake and tsunami, but no one realised until now."Workers at Fukushima are only allowed to be exposed to 250 mSv of ionising radiation per year.

radioactive cesium exceeding the government limit was detected in processed tea made in Tochigi City, about 160km from the troubled Fukushima Daiichi nuclear plant, according to the Tochigi Prefectural Government, who said radioactive cesium was detected in tea processed from leaves harvested in the city in early July. The level is more than 3 times the provisional government limit.

anagisawa's hospital is located approximately 200km from Fukushima, so the health problems she is seeing that she attributes to radiation exposure causes her to be concerned by what she believes to be a grossly inadequate response from the government.From her perspective, the only thing the government has done is to, on April 25, raise the acceptable radiation exposure limit for children from 1 mSv/year to 20 mSv/year.

This has caused controversy, from the medical point of view," Yanagisawa told Al Jazeera. "This is certainly an issue that involves both personal internal exposures as well as low-dose exposures."Junichi Sato, Greenpeace Japan Executive Director, said: "It is utterly outrageous to raise the exposure levels for children to twenty times the maximum limit for adults."

The Japanese government cannot simply increase safety limits for the sake of political convenience or to give the impression of normality."Authoritative current estimates of the health effects of low-dose ionizing radiation are published in the Biological Effects of Ionising Radiation VII (BEIR VII) report from the US National Academy of Sciences.

he report reflects the substantial weight of scientific evidence proving there is no exposure to ionizing radiation that is risk-free. The BEIR VII estimates that each 1 mSv of radiation is associated with an increased risk of all forms of cancer other than leukemia of about 1-in-10,000; an increased risk of leukemia of about 1-in-100,000; and a 1-in-17,500 increased risk of cancer death.

She attributes the symptoms to radiation exposure, and added: "We are encountering new situations we cannot explain with the body of knowledge we have relied upon up until now.""The situation at the Daiichi Nuclear facility in Fukushima has not yet been fully stabilised, and we can't yet see an end in sight," Yanagisawa said. "Because the nuclear material has not yet been encapsulated, radiation continues to stream into the environment."

So far, the only cases of acute radiation exposure have involved TEPCO workers at the stricken plant. Lower doses of radiation, particularly for children, are what many in the medical community are most concerned about, according to Dr Yanagisawa.

Humans are not yet capable of accurately measuring the low dose exposure or internal exposure," she explained, "Arguing 'it is safe because it is not yet scientifically proven [to be unsafe]' would be wrong. That fact is that we are not yet collecting enough information to prove the situations scientifically. If that is the case, we can never say it is safe just by increasing the annual 1mSv level twenty fold."

Her concern is that the new exposure standards by the Japanese government do not take into account differences between adults and children, since children's sensitivity to radiation exposure is several times higher than that of adults.

Al Jazeera contacted Prime Minister Naoto Kan's office for comment on the situation. Speaking on behalf of the Deputy Cabinet Secretary for Public Relations for the Prime Minister's office, Noriyuki Shikata said that the Japanese government "refers to the ICRP [International Commission on Radiological Protection] recommendation in 2007, which says the reference levels of radiological protection in emergency exposure situations is 20-100 mSv per year. The Government of Japan has set planned evacuation zones and specific spots recommended for evacuation where the radiation levels reach 20 mSv/year, in order to avoid excessive radiation exposure."

he prime minister's office explained that approximately 23bn yen ($300mn) is planned for decontamination efforts, and the government plans to have a decontamination policy "by around the end of August", with a secondary budget of about 97bn yen ($1.26bn) for health management and monitoring operations in the affected areas. When questioned about the issue of "acute radiation exposure", Shikata pointed to the Japanese government having received a report from TEPCO about six of their workers having been exposed to more than 250 mSv, but did not mention any reports of civilian exposures.

Prime Minister Kan's office told Al Jazeera that, for their ongoing response to the Fukushima crisis, "the government of Japan has conducted all the possible countermeasures such as introduction of automatic dose management by ID codes for all workers and 24 hour allocation of doctors. The government of Japan will continue to tackle the issue of further improving the health management including medium and long term measures". Shikata did not comment about Kodama's findings.

Nishio Masamichi, director of Japan's Hakkaido Cancer Centre and a radiation treatment specialist, published an article on July 27 titled: "The Problem of Radiation Exposure Countermeasures for the Fukushima Nuclear Accident: Concerns for the Present Situation". In the report, Masamichi said that such a dramatic increase in permitted radiation exposure was akin to "taking the lives of the people lightly". He believes that 20mSv is too high, especially for children who are far more susceptible to radiation.

Kodama is an expert in internal exposure to radiation, and is concerned that the government has not implemented a strong response geared towards measuring radioactivity in food. "Although three months have passed since the accident already, why have even such simple things have not been done yet?" he said. "I get very angry and fly into a rage."

Radiation has a high risk to embryos in pregnant women, juveniles, and highly proliferative cells of people of growing ages. Even for adults, highly proliferative cells, such as hairs, blood, and intestinal epithelium cells, are sensitive to radiation."

Early on in the disaster, Dr Makoto Kondo of the department of radiology of Keio University's School of Medicine warned of "a large difference in radiation effects on adults compared to children".Kondo explained the chances of children developing cancer from radiation exposure was many times higher than adults.

Children's bodies are underdeveloped and easily affected by radiation, which could cause cancer or slow body development. It can also affect their brain development," he said.Yanagisawa assumes that the Japanese government's evacuation standards, as well as their raising the permissible exposure limit to 20mSv "can cause hazards to children's health," and therefore "children are at a greater risk".

Kodama, who is also a doctor of internal medicine, has been working on decontamination of radioactive materials at radiation facilities in hospitals of the University of Tokyo for the past several decades. "We had rain in Tokyo on March 21 and radiation increased to .2 micosieverts/hour and, since then, the level has been continuously high," said Kodama, who added that his reporting of radiation findings to the government has not been met an adequate reaction. "At that time, the chief cabinet secretary, Mr Edano, told the Japanese people that there would be no immediate harm to their health."

n early July, officials with the Japanese Nuclear Safety Commission announced that approximately 45 per cent of children in the Fukushima region had experienced thyroid exposure to radiation, according to a survey carried out in late March. The commission has not carried out any surveys since then.

Now the Japanese government is underestimating the effects of low dosage and/or internal exposures and not raising the evacuation level even to the same level adopted in Chernobyl," Yanagisawa said. "People's lives are at stake, especially the lives of children, and it is obvious that the government is not placing top priority on the people's lives in their measures."Caldicott feels the lack of a stronger response to safeguard the health of people in areas where radiation is found is "reprehensible".

Millions of people need to be evacuated from those high radiation zones, especially the children."

Dr Yanagisawa is concerned about what she calls "late onset disorders" from radiation exposure resulting from the Fukushima disaster, as well as increasing cases of infertility and miscarriages."Incidence of cancer will undoubtedly increase," she said. "In the case of children, thyroid cancer and leukemia can start to appear after several years. In the case of adults, the incidence of various types of cancer will increase over the course of several decades."Yanagisawa said it is "without doubt" that cancer rates among the Fukushima nuclear workers will increase, as will cases of lethargy, atherosclerosis, and other chronic diseases among the general population in the effected areas.

Radioactive food and water

An August 1 press release from Japan's MHLW said no radioactive materials have been detected in the tap water of Fukushima prefecture, according to a survey conducted by the Japanese government's Nuclear Emergency Response Headquarters. The government defines no detection as "no results exceeding the 'Index values for infants (radioactive iodine)'," and says "in case the level of radioactive iodine in tap water exceeds 100 Bq/kg, to refrain from giving infants formula milk dissolved by tap water, having them intake tap water … "

Yet, on June 27, results were published from a study that found 15 residents of Fukushima prefecture had tested positive for radiation in their urine. Dr Nanao Kamada, professor emeritus of radiation biology at Hiroshima University, has been to Fukushima prefecture twice in order to take internal radiation exposure readings and facilitated the study.

The risk of internal radiation is more dangerous than external radiation," Dr Kamada told Al Jazeera. "And internal radiation exposure does exist for Fukushima residents."According to the MHLW, distribution of several food products in Fukushima Prefecture remain restricted. This includes raw milk, vegetables including spinach, kakina, and all other leafy vegetables, including cabbage, shiitake mushrooms, bamboo shoots, and beef.

he distribution of tealeaves remains restricted in several prefectures, including all of Ibaraki, and parts of Tochigi, Gunma, Chiba, Kanagawa Prefectures.Iwate prefecture suspended all beef exports because of caesium contamination on August 1, making it the fourth prefecture to do so.

yunichi Tokuyama, an expert with the Iwate Prefecture Agricultural and Fisheries Department, told Al Jazeera he did not know how to deal with the crisis. He was surprised because he did not expect radioactive hot spots in his prefecture, 300km from the Fukushima nuclear plant."The biggest cause of this contamination is the rice straw being fed to the cows, which was highly radioactive," Tokuyama told Al Jazeera.

Kamada feels the Japanese government is acting too slowly in response to the Fukushima disaster, and that the government needs to check radiation exposure levels "in each town and village" in Fukushima prefecture."They have to make a general map of radiation doses," he said. "Then they have to be concerned about human health levels, and radiation exposures to humans. They have to make the exposure dose map of Fukushima prefecture. Fukushima is not enough. Probably there are hot spots outside of Fukushima. So they also need to check ground exposure levels."

Radiation that continues to be released has global consequences.More than 11,000 tonnes of radioactive water has been released into the ocean from the stricken plant.

Those radioactive elements bio-concentrate in the algae, then the crustaceans eat that, which are eaten by small then big fish," Caldicott said. "That's why big fish have high concentrations of radioactivity and humans are at the top of the food chain, so we get the most radiation, ultimately."

"Cleaning," "waiting," and "dismantling" are the three key actions in this process. Needless to say, this all needs to be done while simultaneously containing radioactive materials.

In the case of the Tokai Nuclear Power Plant, the first commercial plant to undergo decommissioning, spent fuel was removed over a span of three years beginning in 1998, and was transported to Britain for reprocessing. Dismantling of the facilities began in 2001, with current efforts being made toward the dismantling of heat exchangers; workers have not yet begun to take the reactor itself apart. The entire process is expected to be an 88.5-billion-yen project involving 563,000 people.

Hitachi Ltd., which manufactures nuclear reactors, says that it "generally takes about 30 years" to decommission a reactor. The Hamaoka Nuclear Power Plant's No. 1 and No. 2 reactors operated by Chubu Electric Power Co. are also expected to take about 30 years before they are decommissioned.

In the case of the Fukushima No. 1 Nuclear Power Plant, meanwhile, the biggest challenge lies in how to remove the fuel, says Tadashi Inoue, a research advisor at the Central Research Institute of Electric Power Industry (CRIEPI), a foundation that conducts research on energy and environmental issues in relation to the electrical power industry.

"we must deal with rubble contaminated with radioactive materials that were scattered in the hydrogen blasts and treat the radiation-tainted water being used to cool nuclear fuel before we can go on to fuel removal."

Currently, the Fukushima plant's operator, Tokyo Electric Power Co. (TEPCO), is desperately trying to treat the contaminated water. Huge challenges remain with regards to the contaminated rubble, as radiation levels of over 10 sieverts per hour were found near outdoor pipes on the plant grounds just the other day. Exposure to such high levels would mean death for most people.

Each step in the process toward decommissioning is complicated and requires great numbers of people. It's a race against time because the maximum amount of radiation that workers can be exposed to is 250 millisieverts.

Prefacing the following as "a personal opinion," Inoue says: "Building a car that can protect the people inside as much as possible from radioactive materials, and attaching an industrial robotic arm to the car that can be manipulated by those people could be one way to go about it."

Two types of fuel removal must take place. One is to take out the spent fuel in the containment pools, and the other is to remove the melted fuel from the reactor cores. Because the radiation levels of the water in the spent fuel pools have not shown any significant changes from before the crisis, it is believed that the spent fuel has not suffered much damage. However, removing it will require repairing and reinstalling cranes to hoist the fuel rods out.

The breached reactor core is a bigger problem. It is believed that raising water levels inside the reactor has been difficult because of a hole in the bottom of the vessel. It will be necessary to plug the hole, and continue filling the vessel with water while extracting the melted fuel. How to fill the vessel with water is still being debated. If the reactor can be filled with water, steps taken after the 1979 Three Mile Island nuclear accident can serve as a guide because in that case, in which approximately 50 percent of the core had melted, workers were able to fill the reactor with water and remove the fuel within.

Inoue predicts that removal of spent fuel from the containment pools will begin about five years after the crisis, and about 10 years in the case of melted fuel from the reactor core. Work on the four reactors at the Fukushima plant will probably take several years.

"Unless we look at the actual reactors and take and analyze fuel samples, we can't know for sure," Inoue adds. Plus, even if workers succeed in removing the fuel, reprocessing it is an even more difficult task. A review of processing methods and storage sites, moreover, has yet to take place.

Meanwhile, at least one expert says he doesn't believe that workers will be able to remove the melted fuel from the crippled plant.

"If there's 10 sieverts per hour of radiation outside, then the levels must be much higher closer to the reactor core," says Tadahiro Katsuta, an associate professor at Meiji University and an expert in reactor engineering and reactor policy who was once a member of an anti-nuclear non-profit organization called Citizens' Nuclear Information Center (CNIC). "The fuel has melted, and we haven't been able to cool it consistently. If work is begun five or 10 years from now when radiation levels have not yet sufficiently gone down, workers' health could be at serious risk."

Katsuta predicts that it will probably take at least 10 years just to determine whether it is possible to remove the fuel. He adds that it could very well take 50 years before the task of dismantling the reactor and other facilities is completed.

What Katsuta has in mind is a Chernobyl-style concrete sarcophagus, which would entail cloaking the melted tomb with massive amounts of concrete. "How could we simultaneously dismantle four reactors that have been contaminated to the extent that they have by radioactive materials?" asks Katsuta. "Japan has little experience in decommissioning reactors, and this case is quite different from standard decommissioning processes. It's not realistic to think we can revert the site back to a vacant lot. I think we should be considering options such as entombing the site with concrete or setting up a protective dome over the damaged reactor buildings

what we face is a great unknown to all of mankind.

"Until early spring, produce was contaminated (on the surface with radioactive materials) that the No. 1 plant discharged into the atmosphere. But now, the major route of contamination is through plant roots," said Kunikazu Noguchi, a radiation protection expert at Nihon University. Whether absorption by plant roots can affect human health remains to be seen. Experts are warning that the region's soil and agricultural products will require close monitoring for many years.

At the moment, sampling data collected by the various prefectural governments indicate that no vegetables, except for those grown in Fukushima Prefecture, have been found to contain more than the government's provisional limit of 500 becquerels per kilogram since June. Likewise, as of Sept. 7, samples of pork, chicken, milk and fruit had also tested within the provisional radiation limit, apart from Fukushima products and tea from Chiba, Kanagawa, Gunma, Tochigi, Saitama and Ibaraki prefectures.

In fact, the amount of radioactive materials in most of the food sampled has been steadily declining over the past few months, except for produce from Fukushima. "The results of Fukushima's sampling tests show the amountof radioactive material contained in vegetables has dropped sharply in recent months, including those grown in areas with high radiation levels," Noguchi said. "People shouldn't worry about it much (for the time being)," he said. "But mushrooms and other vegetables grown in contaminated forests are likely tocontain high levels of radioactive materials."

Now that soil in a wide area of eastern Japan has been contaminated with cesium, experts are calling for close monitoring of soil and produce. The education ministry conducted soil surveys in June and July at 2,200 locations within 100 km of the crippled plant. At 34 locations in six municipalities in Fukushima Prefecture, including Minamisoma, Namie and Iitate, the data said cesium levels had exceeded 1.48 million becquerels per sq. meter — the same level that was used to define the exclusion zone around Chernobyl in 1986. Yasuyuki Muramatsu, a radiochemistry professor at Gakushuin University, said that agricultural contamination will likely peak this year because cesium binds more strongly with minerals in soil as time passes, making it more difficult to be absorbed by plant roots.

"Data from the Chernobyl disaster show that radioactive cesium in soil tends to become fixed more strongly to clay minerals as time passes. So agricultural contamination will lessen next year," he said. Muramatsu urged that special caution should be taken over products grown in soil rich in organic matter, such as in forested areas. "If the soil is rich in organic matter, it makes (cesium) more easily transferable to plants. . . . Forest soil is rich in organic matter, so people should be careful," he said.

his year, it's very important to conduct thorough surveys. The contamination will continue for a long time, so data collection is essential," Muramatsu said. "We need to be prepared for the following years by recording data this year and studying the rate at which cesium in the soil is absorbed by each kind of produce," Muramatsu said. In the meantime, the radioactivity itself will continue to weaken over the years. Cesium-134 has a half-life of 2 years and cesium-137 a half-life of 30 years, meaning the radiation they emit will drop by half in 2 years and 30 years.

The ratio of cesium-134 to cesium-137 in the Fukushima accident is estimated as 1-to-1, while the ratio during the 1986 Chernobyl disaster was 1-to-2. This indicates the radiation in Fukushima will weaken at a faster rate than at Chernobyl. Between April and early August, the farm ministry tested soil at some 580 locations in six prefectures, including Fukushima, Tochigi and Gunma, to get a better picture of the full extent of contamination.

According to the results, 40 locations in Fukushima Prefecture had an intensity exceeding 5,000 becquerels per kilogram — the government's maximum limit for growing rice. Many municipalities within 30 km of the Fukushima No. 1 plant were banned from planting rice based on similar tests conducted in April. In addition, the ministry has asked 17 prefectures in eastern Japan to conduct two-phase radiation tests on harvested rice.

So far, none of the tests performed on unmilled rice — including from Fukushima — exceeded the government's limit of 500 becquerels per kilogram. Masanori Nonaka, an agriculture professor at Niigata University who specializes in soil science, said rice grown in contaminated areas is likely to be tainted, but to what extent is anyone's guess. White rice, however, may prove to be safe, Nonaka said. Because most of the radioactive material will adhere to the bran — the part of the husk left behind after hulling — about 60 percent of the cesium can be removed just by polishing it, he explained. Other foods, such as marine produce, won't be as easy to handle, experts say. After the Chernobyl accident, for example, the radioactive contamination of fish peaked between 6 to 12 months after the disaster. The Fisheries Agency, meanwhile, has asked nine prefectures on the Pacific coast to increase their sampling rates to prevent contaminated fish from landing in supermarkets.