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I worked at Hamaoka nuclear plant for a little over 5 years, but it was not the only time I’d worked at a power plant. Before Hamaoka, I spent my 30s working at a nearby nuclear plant for about 10 years in the 1980’s. At that time, I did not work at just one site but was moving from one plant to another to do regular maintenance work. Recently, that kind of people are called “Nuclear gypsies” with a bit of contempt and in that period I was living as one of those. Two years after I began the wandering life of a gypsy, I entered for the first time the core container of a steam generator. At the time I was working at the Genkai Nuclear Power Plant in Saga Prefecture. [Editor's note: In brief, there is a containment building within the plant. This houses the core and the steam generator.] The core is the part of the reactor where uranium fuel undergoes nuclear fission. It generates heat which is then passed to The steam generator which produces the steam to power the turbines which turn the generators elsewhere in the plant . The level of radioactivity in the containment building is very high compared to elsewhere [in the plant]. My job involved entering [the generator] and installing a robot monitor that would enable examination of whether there was any damage in the steam generator.

Actually what happened on the day was that another person replaced me and entered the steam generator to install the robot. After the installation was completed, there was a problem in that the robot wouldn’t respond and thus could not be operated from outside. There are many small holes in the walls of the central part of the steam generator and the six (I believe there were six) ‘legs’ of a robot, operated via a remote control, should be able to survey it through those holes. The employees in charge of supervising the installation concluded that there had been a problem in properly positioning the robot’s legs.

If the ‘legs’ are not completely inserted and the robot is left in that position, it could fall down at any time. If that happens, it spells the loss of a precision machine that's said to be worth several hundred million yen. That’s why I was sent in to enter the generator, on very short notice, to replace the robot back to its correct operating position before that happened. I started putting on the gear to enter the housing at a spot near the steam generator. Two workers helped me put it on. I was already wearing two layers of work clothes, and on top of those, I put on Tyvek protective gear made of paper and vinyl, and an airline respirator. Plus, I wrapped a lot of vinyl tape around my neck, my wrists and my ankles, to block even the slightest opening.

Once I finished putting on the protective gear — which honestly looks like an astronaut suit — I headed toward the housing. When I arrived at the area near the housing, two workers were waiting. They were employees of a company called the Japanese Society for Non-Destructive Inspection [JSNDI] and, to my surprise, despite the area being highly radioactive, they were wearing nothing but plain working clothes. They weren’t even wearing masks. The person who appeared to be in charge invited me over and, after a look at my eyes inside the mask, nodded his head a few times. I guess just looking into my eyes he was able to determine that I’d be able to handle working in the core.

He and I went to the steam generator together.

The base of the steam generator more or less reached my shoulder, at slightly less than 1.5m. At the bottom, there was a manhole. The manhole was open, and I immediately realized I would have to climb up into it.

The JSNDI employee in charge put his arm around me and together we approached the manhole. We looked over the edge and peered in. Inside was dark, and the air was dense and stagnant. It felt as though something sinister was living inside. My expression glazed over. A slight sensation of dread came over me. As I approached the manhole, I noticed a ringing in my ears and felt reluctant to go in. When I looked inside, I saw that the robot was attached to the wall indicated by the [JSNDI] employee. It was not properly attached, which is why I had been sent in.

The robot was square-shaped, 40 cm on each side and 20 cm deep. It was called a ‘spider robot’. The JSNDI employee put his face at the edge of the manhole, a third of his face peering in, and diligently explained what I had to do. There was little awareness at the time of the dangers to workers of radiation exposure, but even so I was concerned about the bold act of the employee, who looked inside the housing with me. He continued looking inside, unfazed, and I remember wondering why he wasn’t scared. I was almost completely covered while he wasn’t even wearing a mask. […]

I stood up, climbed the ladder, and pushed my upper body through the manhole. In that second, something grabbed at my head and squeezed hard. A pounding in my ear started right away.

One worker said that right after he entered a nuclear reactor he heard a noise like a moving crab. “zawa,zawa,zawa…” He said that he could still hear this noise after he finished the work. Even after the inspection work, when he went back home, he couldn’t forget that noise. The man ended up having a nervous breakdown. A writer who heard this story spoke to this man and wrote a mystery novel based on that experience. The title of the book is “The crab of the nuclear reactor”. It was published in 1981 and was very popular among us.

I never heard such a crab-like noise but I had the feeling that my head was being tightly constricted and deep in my ears I heard very high-tempo echoes like a sutra “gan, gan, gan”. When I entered the steam generator I stood up all of a sudden and my helmet hit the ceiling. So I had to bend my neck and hold both the arms of the robot in the darkish room. “OK” I screamed. So the robot was unlocked and its feet jumped out of the hole. The entire robot was not as heavy as I had thought. After I matched its feet position in the holes I gave them another OK sign and so it was positioned in the hole. In the dark, when I verified that all the feet had entered into the holes I gave them another OK and jumped out of the manhole. […]

Once outside,] I was almost in shock but looked at the alarm meter and saw that it had recorded a value equal to 180, when the maximum it can record is 200. In only 15 seconds, I was exposed to an unbelievably high level of radiation, 180 millirem. At that time the unit ‘millirem' was used while now it’s different. Now everybody uses sievert. That time I was in charge of an inspection work that lasted about 1 month. After that I worked in another nuclear reactor but even on the second time I couldn’t get through the fear and experienced the same creepy noise.

I think that is true. But those are the locations that have been measured. I think there are many more.Mr. Kinoshita's blog has this bit of "rumor" from his worker at the plant:

As I have said before, I have never seen, or heard about, such steam.It's possible that he doesn't know but someone else may know. 2. About locations that exceed 10 sieverts/hr: In Mr. Kinoshita's blog:

The same worker] also told [his contact] that there are 6 locations that exceed 10,000 millisievert/hr [10 sieverts/hr], unlike what TEPCO has announced. Fukushima worker's tweet:

There are several cracks on the ground near the Containment Vessel, and the steam is coming out from them, not on a regular basis but sporadically. Wait, does that mean the floor of the reactor building is cracked? He doesn't say which reactor. And Fukushima worker has another tweet that says:

In the reactor buildings of Reactors 1, 2 and 3, there are many spots that measure even higher [than 10 sieverts/hr] and we can't go near them.So much for the plant being stable. But so far, the information is unsubstantiated (i.e. not admitted, or denied, by officials at TEPCO or the government). Speaking of the government, it will allow the residents in Okuma-machi and Futaba-machi, where the plant is located, to temporarily return to their homes later this month now that the plant is stable.

Regulations are loosened, and reactors are back in compliance."That's what they say for everything ...," said Demetrios Basdekas, a retired NRC engineer. "Every time you turn around, they say, 'We have all this built-in conservatism.' "The crisis at the decades-old Fukushima Dai-ichi nuclear facility in Japan has focused attention on nuclear safety and prompted the NRC to look at U.S. reactors. A report is due in July.But the factor of aging goes far beyond issues posed by Fukushima.

Commercial nuclear reactors in the United States were designed and licensed for 40 years. When the first were built in the 1960s and 1970s, it was expected that they would be replaced with improved models long before their licenses expired.That never happened. The 1979 accident at Three Mile Island, massive cost overruns, crushing debt and high interest rates halted new construction in the 1980s.Instead, 66 of the 104 operating units have been relicensed for 20 more years. Renewal applications are under review for 16 other reactors.As of today, 82 reactors are more than 25 years old.The AP found proof that aging reactors have been allowed to run less safely to prolong operations.

Last year, the NRC weakened the safety margin for acceptable radiation damage to reactor vessels -- for a second time. The standard is based on a reactor vessel's "reference temperature," which predicts when it will become dangerously brittle and vulnerable to failure. Through the years, many plants have violated or come close to violating the standard.As a result, the minimum standard was relaxed first by raising the reference temperature 50 percent, and then 78 percent above the original -- even though a broken vessel could spill radioactive contents."We've seen the pattern," said nuclear safety scientist Dana Powers, who works for Sandia National Laboratories and also sits on an NRC advisory committee. "They're ... trying to get more and more out of these plants."

Sharpening the pencilThe AP study collected and analyzed government and industry documents -- some never-before released -- of both reactor types: pressurized water units that keep radioactivity confined to the reactor building and the less common boiling water types like those at Fukushima, which send radioactive water away from the reactor to drive electricity-generating turbines.The Energy Northwest Columbia Generating Station north of Richland is a boiling water design that's a newer generation than the Fukushima plants.Tens of thousands of pages of studies, test results, inspection reports and policy statements filed during four decades were reviewed. Interviews were conducted with scores of managers, regulators, engineers, scientists, whistleblowers, activists and residents living near the reactors at 65 sites, mostly in the East and Midwest.

AP reporters toured some of the oldest reactors -- Oyster Creek, N.J., near the Atlantic coast 50 miles east of Philadelphia and two at Indian Point, 25 miles north of New York City on the Hudson River.Called "Oyster Creak" by some critics, this boiling water reactor began running in 1969 and is the country's oldest operating commercial nuclear power plant. Its license was extended in 2009 until 2029, though utility officials announced in December they will shut the reactor 10 years earlier rather than build state-ordered cooling towers. Applications to extend the lives of pressurized water units 2 and 3 at Indian Point, each more than 36 years old, are under NRC review.Unprompted, several nuclear engineers and former regulators used nearly identical terminology to describe how industry and government research has frequently justified loosening safety standards. They call it "sharpening the pencil" or "pencil engineering" -- fudging calculations and assumptions to keep aging plants in compliance.

Cracked tubing: The industry has long known of cracking in steel alloy tubing used in the steam generators of pressurized water reactors. Ruptures have been common in these tubes containing radioactive coolant; in 1993 alone, there were seven. As many as 18 reactors still run on old generators.Problems can arise even in a newer metal alloy, according to a report of a 2008 industry-government workshop.

Neil Wilmshurst, director of plant technology for the industry's Electric Power Research Institute, acknowledged the industry and NRC often collaborate on research that supports rule changes. But he maintained there's "no kind of misplaced alliance ... to get the right answer."Yet agency staff, plant operators and consultants paint a different picture:* The AP reviewed 226 preliminary notifications -- alerts on emerging safety problems -- NRC has issued since 2005. Wear and tear in the form of clogged lines, cracked parts, leaky seals, rust and other deterioration contributed to at least 26 of the alerts. Other notifications lack detail, but aging was a probable factor in 113 more, or 62 percent in all. For example, the 39-year-old Palisades reactor in Michigan shut Jan. 22 when an electrical cable failed, a fuse blew and a valve stuck shut, expelling steam with low levels of radioactive tritium into the outside air. And a 1-inch crack in a valve weld aborted a restart in February at the LaSalle site west of Chicago.

* A 2008 NRC report blamed 70 percent of potentially serious safety problems on "degraded conditions" such as cracked nozzles, loose paint, electrical problems or offline cooling components.* Confronted with worn parts, the industry has repeatedly requested -- and regulators often have allowed -- inspections and repairs to be delayed for months until scheduled refueling outages. Again and again, problems worsened before being fixed. Postponed inspections inside a steam generator at Indian Point allowed tubing to burst, leading to a radioactive release in 2000. Two years later, cracking grew so bad in nozzles on the reactor vessel at the Davis-Besse plant near Toledo, Ohio, that it came within two months of a possible breach, an NRC report said, which could release radiation. Yet inspections failed to catch the same problem on the replacement vessel head until more nozzles were found to be cracked last year.

Time crumbles thingsNuclear plants are fundamentally no more immune to aging than our cars or homes: Metals grow weak and rusty, concrete crumbles, paint peels, crud accumulates. Big components like 17-story-tall concrete containment buildings or 800-ton reactor vessels are all but impossible to replace. Smaller parts and systems can be swapped but still pose risks as a result of weak maintenance and lax regulation or hard-to-predict failures.Even mundane deterioration can carry harsh consequences.For example, peeling paint and debris can be swept toward pumps that circulate cooling water in a reactor accident. A properly functioning containment building is needed to create air pressure that helps clear those pumps. But a containment building could fail in a severe accident. Yet the NRC has allowed safety calculations that assume the buildings will hold.

In a 2009 letter, Mario V. Bonaca, then-chairman of the NRC's Advisory Committee on Reactor Safeguards, warned that this approach represents "a decrease in the safety margin" and makes a fuel-melting accident more likely.Many photos in NRC archives -- some released in response to AP requests under the federal Freedom of Information Act -- show rust accumulated in a thick crust or paint peeling in long sheets on untended equipment.Four areas stand out:

Brittle vessels: For years, operators have rearranged fuel rods to limit gradual radiation damage to the steel vessels protecting the core and keep them strong enough to meet safety standards.But even with last year's weakening of the safety margins, engineers and metal scientists say some plants may be forced to close over these concerns before their licenses run out -- unless, of course, new regulatory compromises are made.

Leaky valves: Operators have repeatedly violated leakage standards for valves designed to bottle up radioactive steam in an earthquake or other accident at boiling water reactors.Many plants have found they could not adhere to the general standard allowing main steam isolation valves to leak at a rate of no more than 11.5 cubic feet per hour. In 1999, the NRC decided to allow individual plants to seek amendments of up to 200 cubic feet per hour for all four steam valves combined.But plants have violated even those higher limits. For example, in 2007, Hatch Unit 2, in Baxley, Ga., reported combined leakage of 574 cubic feet per hour.

"Many utilities are doing that sort of thing," said engineer Richard T. Lahey Jr., who used to design nuclear safety systems for General Electric Co., which makes boiling water reactors. "I think we need nuclear power, but we can't compromise on safety. I think the vulnerability is on these older plants."Added Paul Blanch, an engineer who left the industry over safety issues, but later returned to work on solving them: "It's a philosophical position that (federal regulators) take that's driven by the industry and by the economics: What do we need to do to let those plants continue to operate?"Publicly, industry and government say that aging is well under control. "I see an effort on the part of this agency to always make sure that we're doing the right things for safety. I'm not sure that I see a pattern of staff simply doing things because there's an interest to reduce requirements -- that's certainly not the case," NRC chairman Gregory Jaczko said in an interview.

Corroded piping: Nuclear operators have failed to stop an epidemic of leaks in pipes and other underground equipment in damp settings. Nuclear sites have suffered more than 400 accidental radioactive leaks, the activist Union of Concerned Scientists reported in September.Plant operators have been drilling monitoring wells and patching buried piping and other equipment for several years to control an escalating outbreak.But there have been failures. Between 2000 and 2009, the annual number of leaks from underground piping shot up fivefold, according to an internal industry document.

According to Asahi Shinbun (9/24/2011), TEPCO thinks:

"Under the steam are the reactors. It could be either the steam is escaping from the reactor, or the rainwater is evaporating on the lid of the reactor which is hot."Looking at the videos, they do not look like rainwater being evaporated, as the steam comes out unevenly and sporadically. If it's rainwater I would imagine a steady rise of steam.

The power plant’s electricity generation capacity (basically, how much it can generate) is 110-MW, which makes it one of the larger-scale solar power plants out there today.You might have guessed by now that this type of power plant is able to provide electricity at night, and all week, because it stores heat in the form of salt that is released in the evening so that the plant can continue to generate electricity when it is dark, cloudy, or stormy.

Now it is known that radioactive material, the melted core, is moving under the ground away from where it the measuring was being done according to Dr. Jacobs. He said that the reactors were not safe for earthquakes and there is evidence that Reactor #1 was melting down when the tsunami hit, putting reliability in question. 

There are continual aftershocks at the level of a 6.0, so when you have a fragile structure and what we have now, the radioactive core has melted down into the basement, into the bottom of the containment vessel. 

Russia Today reporting that new evidence suggests Fukushima's nuclear reactors were doomed to cripple even before the massive wave reached them adds weight to the unreliability of nuclear energy according to Dr. Jacobs. Canadians receiving extreme radiation in Tuesday rainout

Mainchi points out that reactors 1 and 3 are probably in no better shape: The fuel inside the Nos. 1 to 3 reactors is believed to have melted through the pressure vessels and been accumulating in the outer primary containers after the Fukushima plant lost its key functions to cool the reactors in the wake of the earthquake and tsunami on March 11 last year.

The Brunswick Nuclear Plant has two boiling-water reactors that generate 1,875 megawatts of electricity. Each of the Brunswick reactors is refueled once every 24 months, usually in the spring when the demand for electricity is relatively low. At the Brunswick Plant, 1 million gallons of water per minute are pumped from the Cape Fear River where it passes through the plant’s cooling system and then drops approximately  15 feet to the head of the outflow canal.

Refueling procedures are elaborate and well documented procedures, and one of the biggest questions is why the proper procedures were not followed, or were carried out incorrectly. The bolts need to be tensioned in a specific Torque Pattern, which generally includes multiple passes.  Refueling procedures require a crew of  at least 6 engineers, and additional Quality Control inspectors.

The Tensioning Tool is inspected and maintained, and is also part of the QC checklist.  This is not a simple situation where someone didn’t torque down the bolts correctly, as multiple personnel would have had to check and confirm the status prior to restart. In fact, according to Progress Energy’s 35 day outage schedule, the reassembly and reactor test are the 9th, and 10th steps of the process, and one can’t help but wonder why this was not detected before the reactor was re-pressurized. Chris had some very good questions regarding the Brunswick event, that I felt were worth sharing.

What testing was performed to determine that the RPV Head was Tensioned properly? What caused the improper Tensioning ? Procedure, Skill of the Craft? Aggressive Schedule? What are the Acceptance Criteria in the procedure for a properly tensioned head” How do you know that you meet the Acceptance Criteria?

Not only are the procedures and QC process in question, but the event also impacts operations and reliability of reactor components.  Chris highlighted a few questions that he felt were critical to ensure safe restart and operation.

Could there have been Foreign Material on the RPV Head Flange? What damage to surrounding equipment in the Drywell was sustained by the Steam/Water Leak? What is the condition of the Refueling Seal, now that it has been sprayed with Steamy/Hot Water? Did Hot/Steamy water find its way on the Outside of the Containment such that Corrosion in the future will be a problem? Did the steam leakage affect the Reactor Vessel Head Studs and their Threaded Holes (in the Reactor Vessel Flange) such that they will fail at a future date? At this point, Progress Energy is keeping fairly quiet about the specifics, and initially only revealed information of a “possible leak at the top of the reactor vessel”.  Monday morning should prove eventful not only for the Utility, but also for regulators.

Solar power. While sunlight is renewable -- for at least another four billion years -- photovoltaic panels are not. Nor is desert groundwater, used in steam turbines at some solar-thermal installations. Even after being redesigned to use air-cooled condensers that will reduce its water consumption by 90 percent, California's Blythe Solar Power Project, which will be the world's largest when it opens in 2013, will require an estimated 600 acre-feet of groundwater annually for washing mirrors, replenishing feedwater, and cooling auxiliary equipment.

Geothermal power. These projects also depend on groundwater -- replenished by rain, yes, but not as quickly as it boils off in turbines. At the world's largest geothermal power plant, the Geysers in California, for example, production peaked in the late 1980s and then the project literally began running out of steam.

Wind power. According to the American Wind Energy Association, the 5,700 turbines installed in the United States in 2009 required approximately 36,000 miles of steel rebar and 1.7 million cubic yards of concrete (enough to pave a four-foot-wide, 7,630-mile-long sidewalk). The gearbox of a two-megawatt wind turbine contains about 800 pounds of neodymium and 130 pounds of dysprosium -- rare earth metals that are rare because they're found in scattered deposits, rather than in concentrated ores, and are difficult to extract.

Biomass.

t expanding energy crops will mean less land for food production, recreation, and wildlife habitat. In many parts of the world where biomass is already used extensively to heat homes and cook meals, this renewable energy is responsible for severe deforestation and air pollution

Hydropower.

"renewable energy" is a meaningless term with no established standards.

The amount of concrete and steel in a wind-tower foundation is nothing compared with Grand Coulee or Three Gorges, and dams have an unfortunate habit of hoarding sediment and making fish, well, non-renewable.

All of these technologies also require electricity transmission from rural areas to population centers. Wilderness is not renewable once roads and power-line corridors fragment it

the life expectancy of a solar panel or wind turbine is actually shorter than that of a conventional power plant.

meeting the world's total energy demands in 2030 with renewable energy alone would take an estimated 3.8 million wind turbines (each with twice the capacity of today's largest machines), 720,000 wave devices, 5,350 geothermal plants, 900 hydroelectric plants, 490,000 tidal turbines, 1.7 billion rooftop photovoltaic systems, 40,000 solar photovoltaic plants, and 49,000 concentrated solar power systems. That's a heckuva lot of neodymium.

hydroelectric power from dams is a proved technology. It already supplies about 16 percent of the world's electricity, far more than all other renewable sources combined.

None of our current energy technologies are truly renewable, at least not in the way they are currently being deployed. We haven't discovered any form of energy that is completely clean and recyclable, and the notion that such an energy source can ever be found is a mirage.

Long did the math for California and discovered that even if the state replaced or retrofitted every building to very high efficiency standards, ran almost all of its cars on electricity, and doubled its electricity-generation capacity while simultaneously replacing it with emissions-free energy sources, California could only reduce emissions by perhaps 60 percent below 1990 levels -- far less than its 80 percent target. Long says reaching that target "will take new technology."

it will also take a new honesty about the limitations of technology

The plant is essentially full of water … injecting more water into the plant can only happen if some of it boils off, which releases radioactive steam into the air (which is, essentially, what has been happening for weeks). The current plan is to decontaminate the water and use the decontaminated water to cool the plant.

There is no evidence that water is no longer leaking into the sea or steam into the air.

rate of escape is only somewhat slowed down, and the prospect of additional catastrophic events such as the collapse of a structure or an explosion is still very real.

possibility of a hydrogen explosion

There is still a distinct

Indonesia has signed contracts for 2.3 gigawatts of plants, Bloomberg New Energy Finance data show. A gigawatt is about equal to the output of a new atomic reactor, and requires $2 billion to $4 billion of investment. “There’s a remarkable opportunity for Indonesia to increase the amount of power generated from geothermal,” says Stephen W. Green, former head of Chevron’s Indonesia and Philippines operations and now its vice-president of policy, government, and public affairs. “There are synergies between oil and geothermal and it makes sense for us to exploit that.”

Unocal negotiated Indonesia’s first foreign-partnership geothermal license in 1982 with the help of U.S. President Barack Obama’s late stepfather, Lolo Soetoro, who worked for the U.S. company as a government liaison. Chevron acquired Unocal in 2005. At the plant in Java, which lies inside a nature preserve, hot water and steam are pumped from as deep as 10,535 feet below the earth’s surface through 34 miles of pipes to turn turbines to make power. Each well takes as much as 90 days to drill and costs up to $7 million, Chevron says. The company is now planning additional plants in Indonesia, including a potential 200-MW facility in South Sumatra.

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.

"The question is, what is a reasonable interval to give people information?" said Dr. Robert Peter Gale, an American physician and expert on radiation who consulted on the 1986 nuclear disaster in Chernobyl and is now advising Japan's government. "Instead of just releasing each data point you get, sometimes it's better to base things on an average of readings over a period of time." Source: LA Times

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