Strontium 90

‘Deadly’ radioactive material up around 50,000,000% at Fukushima plant in recent months — Strontium-90 spikes to record level near ocean outside Reactor No. 2

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1-17_Sr-90_11-27

– “Deadly” radioactive material up around 50,000,000% at Fukushima plant in recent months — Strontium-90 spikes to record level near ocean outside Reactor No. 2 (ENEnews, Dec 6, 2014):

TEPCO — Detailed Analysis Results in the Port of Fukushima Daiichi NPS, around Discharge Channel and Bank Protection, Nov. 27, 2014:

Most recent report on Strontium-90 concentration in underground observation hole No. 1-17:

First report on Strontium-90 concentration in underground observation hole No. 1-17:

Read more‘Deadly’ radioactive material up around 50,000,000% at Fukushima plant in recent months — Strontium-90 spikes to record level near ocean outside Reactor No. 2

Ocean hits record high for radioactive Strontium at all 6 locations near Fukushima reactors — Levels up to 20 times higher than reported last week

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– Ocean hits record high for radioactive Strontium at all 6 locations near Fukushima reactors — Levels up to 20 times higher than reported last week — Officials: Contamination from highly radioactive ‘debris’ is seeping into ground and flowing out to sea (ENENews, Sep 15, 2014):

TEPCO Prompt Report of Result of Analysis, Sept. 10, 2014:

Port of Fukushima Daiichi, around Discharge Channel and Bank Protection — Seawater

ocean_port_Sr_90_91014

This newly published data shows record levels of Strontium-90 have been detected at all 6 seawater monitoring locations in front of the destroyed reactors. At 3 of 6 locations levels are around triple the previous record set last year.

Read moreOcean hits record high for radioactive Strontium at all 6 locations near Fukushima reactors — Levels up to 20 times higher than reported last week

Officials reveal about 2 Trillion becquerels of Fukushima radioactive material flowed into ocean every month during 2013 — “Deadly strontium” releases now more than double cesium — “Strontium gets into your bones… it changes the equation” (VIDEO)

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– Officials reveal about 2 Trillion becquerels of Fukushima radioactive material flowed into ocean every month during 2013 — “Deadly strontium” releases now more than double cesium — “Strontium gets into your bones… it changes the equation” (VIDEO (ENENews, Aug 29, 2014)

Fukushima: Strontium-90 And Other β Nuclides In Reactor No. 2 Groundwater Jump 1,000 Times Higher

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– All β nuclide density in reactor2 groundwater 1,000 times much as before Feb / 10 times much in plant port too (Fukushima Diary, June 8, 2014):

All β nuclide (including Strontium-90) density in groundwater jumped up by 1,000 times since this February, according to Tepco.

It is from Tepco’s report about groundwater contamination released on 6/6/2014. The location is in the seaside of reactor2.

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Strontium Reaches 500 Billion Bq/m³ In Basements At Fukushima – Record Levels Reported At 5 Locations Near Ocean

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– Strontium reaches 500 Billion Bq/m³ in basements at Fukushima — Record levels reported at 5 locations near ocean — U.S. Senior Scientist: “We see strontium becoming more of concern… food chain will have to be studied more carefully” (ENENews, June 3, 2014):

Fukushima: 5,000,000,000 Bq/m3 Of Strontium-90 Water Got On Worker’s Boots … TEPCO Spokesman: ‘I’m sorry.’

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– Fukushima worker “5,000,000,000 Bq/m3 of Strontium-90 water got on the boots” / Tepco “I’m sorry.” (Fukushima Diary, Feb 8, 2014):

Following up this article..Tepco been mis-analyzing Strontium-90 in contaminated water and seawater for 2.5 years since 311 [URL]

Fukushima workers were building the underground wall only a few meters away from the location that they measured 5,000,000,000 Bq/m3 of Strontium-90 from the groundwater of. However, Tepco didn’t inform the workers of the contamination level for over half a year.

The extremely contaminated water got on the boots of workers while they were injecting the chemical material underground. They had to pile macadams up to 1m high with the lead plate on the top to avoid the contamination, according to Tepco.

Read moreFukushima: 5,000,000,000 Bq/m3 Of Strontium-90 Water Got On Worker’s Boots … TEPCO Spokesman: ‘I’m sorry.’

Strontium-90 160,000 Times Over Limit Detected At Pacific Ocean – Groundwater Levels Exceeded Detection Limit

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– Kyodo: ‘Massive’ amount of Fukushima data wrong? “Figures can’t be trusted” — NHK: Strontium-90 by ocean at 160,000 times limit — Tepco: Actual levels “exceeded the upper limit of measurement… We are very sorry” (ENENews, Feb 7, 2014):

Kyodo, Feb. 7, 2014: TEPCO to review “massive” radiation data due to improper measurement – [TEPCO] said Friday that it will review a “massive” amount of radiation data it has collected at the crippled Fukushima Daiichi nuclear power plant because readings may be lower than actual figures due to improper measurement. “We are very sorry, but we found cases in which beta radiation readings turned out to be wrong when the radioactivity concentration of a sample was high,” TEPCO spokesman Masayuki Ono told a press conference. […]

Kyodo/Jiji, Feb. 7, 2014: [TEPCO] said it will re-analyze past water samples because some of the figures can’t be trusted.

Read moreStrontium-90 160,000 Times Over Limit Detected At Pacific Ocean – Groundwater Levels Exceeded Detection Limit

Record-High 10 Million Bq/Liter Of Strontium-90 & Beta Emitters In Fukushima Plant Groundwater – 1,000% More Than Tepco Has Claimed For Last 6 Months

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Fukushima Plant Groundwater

– Record-high 10 Million Bq/liter of strontium-90 & beta emitters finally revealed in Fukushima plant groundwater — 1,000% more than Tepco has claimed for last 6 months (ENENews, Feb 6, 2014):

Jiji Press, Feb. 6, 2014: TEPCO Corrects Last Summer’s Water Pollution Data to Record High […] Samples collected from an observation well close to the sea in early July contained a record 5 million becquerels of strontium-90 per liter of groundwater, the company said. When TEPCO announced the original data that month, the firm said the total amount of radioactive materials emitting beta particles, including strontium-90, was 900,000 becquerels […] the total amount of beta particle-emitting materials […]  are likely to be around 10 million becquerels, far higher than the previous record high of 3.1 million becquerels for the well.

Kyodo News, Feb. 6, 2014: Record-high strontium-90 in past Fukushima plant groundwater sample — [TEPCO] said Thursday that a groundwater sample taken from a well at the site in July last year contained a record-high 5 million becquerels per liter of radioactive strontium-90.[…] TEPCO official said that “all beta radiation could have been 10 million becquerels in total.”

Read moreRecord-High 10 Million Bq/Liter Of Strontium-90 & Beta Emitters In Fukushima Plant Groundwater – 1,000% More Than Tepco Has Claimed For Last 6 Months

Officials: Tons of Fukushima radioactive waste in area beyond Tokyo, 150 miles from reactors – Higher strontium levels there than spot 1 mile from Daiichi plant

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– Officials: Tons of Fukushima radioactive waste in area beyond Tokyo, 150 miles from reactors — Higher strontium levels there than spot 1 mile from Daiichi plant — “Southern wind directions and rainfall explain relatively high activity levels” (ENENews, Feb 1, 2014):

Asahi Shimbun, Feb. 1, 2014: Sludge designated radioactive waste for 1st time in Kanagawa — The Environment Ministry has classified 2.9 tons of sludge from Prefecture as radioactive waste derived from the Fukushima nuclear disaster, the first such designation for the prefecture on the southern border of Tokyo. The designation, made in December, means the ministry is responsible for disposing of the radioactive sludge. […]  Yokohama city government officials said the designation covers sludge from rain collection and storage facilities at 17 municipal elementary, junior high and other schools. […] The designation also included sludge collected from roadside ditches and elsewhere […] Waste containing more than 8,000 becquerels of radioactive cesium, spewed from the crippled Fukushima No. 1 nuclear power plant, per kilogram is eligible for the designation. […]

Concentration of Strontium-90 at Selected Hot Spots in Japan, PLOS ONE (Scientific Journal), March 2013:

Read moreOfficials: Tons of Fukushima radioactive waste in area beyond Tokyo, 150 miles from reactors – Higher strontium levels there than spot 1 mile from Daiichi plant

Radiation At Fukushima Well Hits Another ‘Record High’: Beta Ray-Emitting Radioactivity At More Than 2.7 Million Becquerels Per Liter

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– Radiation at Fukushima well hits ‘record high’ (RT, Jan 18, 2014):

A record high level of beta rays released from radioactive strontium-90 has been detected at the crippled Fukushima nuclear power plant beneath the No. 2 reactor’s well facing the ocean, according to the facility’s operator.

Tokyo Electric Power Company (TEPCO) measured the amount of beta ray-emitting radioactivity at more than 2.7 million becquerels per liter, Fukushima’s operator said as reported in Japanese media. The measurements were taken on Thursday.

Read moreRadiation At Fukushima Well Hits Another ‘Record High’: Beta Ray-Emitting Radioactivity At More Than 2.7 Million Becquerels Per Liter

Fukushima’s Gigantic Strontium-90 Release

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– Study finds giant strontium-90 release into body of water begins around 1,000 days after meltdown — Dec. 5, 2013 = thousand days after 3/11 — Graphic shows very high levels being discharged for up to 50,000 days (ENENEws, Dec 2, 2013):

Background information on Fukushima

Arjun Makhijani, nuclear expert and President of the Institute for Energy and Environmental Research: Ground water is contacting the molten fuel and becoming extremely contaminated […] The fuel is molten and the bottom of the reactor building is undoubtedly damaged. So that’s why the ground water flowing past the trenches and pipes and past the basement of the reactor building is getting into the reactor building where the molten fuel is. It may also be that the molten fuel is in the cracks of the foundation.

Associated Press: The turbine buildings at the Fukushima Dai-ichi plant are about 150 meters (500 feet) from the ocean. According to a Japan Atomic Energy Agency document, the contaminated underground water is spreading toward the sea at a rate of about 4 meters (13 feet) a month. At that rate, “the water from that area is just about to reach the coast,” if it hasn’t already, said Atsunao Marui, an underground water expert […] on a government committee studying the contaminated water problem. “We must contain the problem as quickly as possible.”

Read moreFukushima’s Gigantic Strontium-90 Release

Record Radioactivity Level Found At Fukushima Plant Well (Asahi Shimbun, Nov 12, 2013)

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– Record radioactivity level found at Fukushima plant well (Asahi Shimbun, Nov 12, 2013):

A record high level of 710,000 becquerels of beta-ray sources, such as radioactive strontium, was detected per liter of water in an observation well at the crippled Fukushima No. 1 nuclear plant.

Tokyo Electric Power Co. said Nov. 12 the water was taken Nov. 10 at the well 10 meters north of a tank that leaked 300 tons of highly contaminated water before the problem was discovered in August.

The previous high reading of 550,000 becquerels per liter was found in water sampled Nov. 9 at the same well.

Read moreRecord Radioactivity Level Found At Fukushima Plant Well (Asahi Shimbun, Nov 12, 2013)

Fukushima: Giant Spike In Radiation Levels After Typhoon Wipha – High Levels Of Strontium May Have Been Flowing Directly Into Pacific Ocean

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– ‘Typhoon appears to have affected Fukushima Daiichi plant” — Giant spike in radioactivity after #Wipha — Suspected of causing high levels of strontium to flow into Pacific (VIDEO) (ENENews, Oct 17, 2013):

NHK Newsline, Oct. 17, 2013: “The typhoon also appears to have affected the damaged Fukushima Daiichi power plant.”

Read moreFukushima: Giant Spike In Radiation Levels After Typhoon Wipha – High Levels Of Strontium May Have Been Flowing Directly Into Pacific Ocean

Japan Journalist: Plutonium, Uranium Escaped Fukushima Reactors As Gas – Can’t Be Detected With Geiger Counter – Terrible Things Looming For Children, Must Be Evacuated Yet Nothing’s Done … This Is A ‘Criminal Nation’

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– Japan Journalist: Plutonium escaped Fukushima reactors as gas, it was a colossal 9,000ºF inside — Can’t be detected with Geiger counter — Terrible things are looming for the children, they must be evacuated yet nothing’s done… This is a “criminal nation” — I’m worried (VIDEO) (ENENews, Oct 16, 2013):

Title: Takashi HIROSE
Source: Yonaoshi 3.11
Date: Mar. 8, 2013

Transcript Excerpts

At 0:45 in

Hirose Takashi, journalist/former engineer: As we speak, radioactive material is seeping through Fukushima’s ground. It makes its way underground, reaches the ocean, to finally end up in the sky.

This kind of fact does not make the news, so everyone forgets about it. If that was talked about every day in the news, the Japanese population couldn’t ignore it. […] In my opinion mass media bear most of the responsibility for it. […] Incidents happen because mass media never take the problem seriously.

Read moreJapan Journalist: Plutonium, Uranium Escaped Fukushima Reactors As Gas – Can’t Be Detected With Geiger Counter – Terrible Things Looming For Children, Must Be Evacuated Yet Nothing’s Done … This Is A ‘Criminal Nation’

Nuclear Expert: Plutonium From Fukushima In Pacific Fish Presents Cancer Risk

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– Nuclear Expert: Plutonium from Fukushima in Pacific fish presents health risk — Study: “Long-distance transport” of Fukushima-sourced plutonium should be addressed (ENENews, Oct 3, 2013):

Georgia Straight (Canada), Oct. 2, 2013 (Emphasis Added): […] Two nuclear experts who saw the Straight’s figures said the real cancer toll could be 100 times higher—or 80,000 cancers. […] That could be the toll, [Daniel Hirsch, a nuclear-policy lecturer at the University of California at Santa Cruz, said in a phone interview], if all factors are taken into account, including: future fish consumption; highly damaging isotopes that were released in the disaster but aren’t being monitored, such as strontium 90 and plutonium 239; consumption of contaminated fish caught in the entire Pacific; and research suggesting that radiation causes many more cancers than official formulas predict. […] “Apologists say it’s a large ocean and dilution is the solution to pollution […] Dilution actually does nothing except expose a larger population.” […] The cancer numbers also don’t include other possible health impacts from radiation in the fish, such as heart disease, stillbirths, and genetic damage to subsequent generations. […]

Read moreNuclear Expert: Plutonium From Fukushima In Pacific Fish Presents Cancer Risk

Japan Finds Highly Toxic Strontium In Fukushima Groundwater (Reuters)

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– Japan finds highly toxic strontium in Fukushima groundwater (Reuters, June 19, 2013):

TOKYO (Reuters) – High levels of a toxic substance called strontium-90 have been found in groundwater at the devastated Fukushima nuclear power plant in Japan, the utility that runs the facility said on Wednesday.

Strontium-90 is a by-product of the fission of uranium and plutonium in nuclear reactors as well as nuclear weapons, the U.S. Environmental Protection Agency says on its website.

The discovery of rising levels of such radioactive material is likely to complicate efforts by the utility, Tokyo Electric Power Co, to get approval to release into the Pacific Ocean what it calls water contaminated with low levels of radiation.

“This contaminated water should not be released to the ocean,” said Michiaki Furukawa, a nuclear chemist and professor emeritus at Nagoya University. “They have to keep it somewhere so that it can’t escape outside the plant.”

Read moreJapan Finds Highly Toxic Strontium In Fukushima Groundwater (Reuters)

Plutonium Leak At U.S. Nuclear Site Hidden From Public – Official: ‘A Very Deliberate Cover Up … We Were Lied To’ (VIDEO)

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Plutonium – the deadliest substance on the planet – has been injected into dogs and no dose was low enough to not give those dogs cancer, according to Dr. Helen Caldicott.

– ‘Amazing’: Plutonium leak at U.S. nuclear site hidden from public — Official: “A very deliberate cover up… I will use the word that we were lied to” (VIDEO) (ENENews, May 22, 2013)

 

Fukushima: Radioactive Strontium-90 To Contaminate Coastal Groundwater In About 10 Years

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– Radioactive water problems at Fukushima nuke plant force rethink (Kyodo News, April 20, 2013):

TOKYO – The government and Tokyo Electric Power Co. will present broad new thinking in May on ways to prevent radioactive water from increasing at the crippled Fukushima Daiichi nuclear power plant, industry minister Toshimitsu Motegi said Friday.

Motegi made the remarks during a meeting to discuss the decommissioning process of the plant’s stricken reactors, as TEPCO continues to grapple with water leaks found recently at several underground storage tanks at the site.

The Nuclear Regulation Authority released an estimate the same day that the leaks could lead to the density of radioactive strontium in groundwater exceeding the legal limit in about 10 years in the coastal area of the plant.

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Fukushima: Radiation, Politics and Public Relations – Part II (Veterans Today)

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MUST-READ!

– Fukushima: Radiation, Politics and Public Relations II (Veterans Today, Nov 11, 2012):

by Leuren Moret, Dr. Majia Nadesan and Jim Fetzer (with Major William Fox)

On Friday, 30 March 2012, Dr. Majia Nadesan and Leuren Moret appeared as the featured guests on “The Real Deal” hosted by Jim Fetzer to discuss the radiation effects of the Fukushima disaster and the fashion in which it has been covered up both by the Japanese and the American governments and media.  Dr. Nadesan, a professor of communication in the Division of Social and Behavioral Sciences in the New College of Interdisciplinary Arts and Sciences at Arizona State University, has studied Fukushima extensively.  Ms. Moret is an independent geoscientist who has done expert studies on the Fukushima disaster and radiation problems around the world, including depleted uranium.  What they had to tell us smacks of politics and public relations and is profoundly disturbing. This is Part II of the original interview, which can be heard here.

Introduction

by Major William Fox

NOTE: I invited Major William Fox (former USMCR commissioned officer), who was instrumental in arranging this interview to prepare an introduction. His key point is that the first line of defense to handle any major crisis is accurate information. Tragically, not only has accurate information been deliberately withheld from Americans regarding the Fukushima crisis, but they have also been steadily fed disinformation.  He continues:

The stealth dirty nuclear war currently being visited upon America goes far beyond government and major media disinformation, although there is certainly plenty of the latter as well as the former.  Dr. Majia Nadesan stated in this interview,

“In June it was reported in the Japanese press that there was actually melt-through. A melt-through is when the melted corium melts through all levels of containment. And not a single U.S. media — I did a search using EBSCO and using LexisNexis to see if any U.S. media picked up in June the Japanese report about the melt-through, and not one single U.S. media picked up that story. A melt-through means that the situation is out of control. Corium is sinking deeper into the ground while sporadically undergoing `limited criticalities’ and releasing ever more extremely dangerous volumes of contamination into the atmosphere, ground water, and ocean. The entire public in Japan, North America, and elsewhere needs to understand how this situation remains out of control.”

The failure to report these melt-throughs was followed by the Japanese government’s big lie perpetrated in December 2011 that all the reactors were in “cold shut down,” implying that all the melted nuclear fuel remained safely within their containment chambers and were subject to stable cooling systems which guaranteed against any further criticalities or radiation releases. Nothing could have been further from the truth. .

Read moreFukushima: Radiation, Politics and Public Relations – Part II (Veterans Today)

Fukushima: Radiation, Politics And Public Relations – Part I (Veterans Today)

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MUST-READ!

– Fukushima: Radiation, Politics and Public Relations (Veterans Today, Nov 11, 2012):

by Leuren Moret, Dr. Majia Nadesan and Jim Fetzer (with Major William Fox)

On Friday, 30 March 2012, Dr. Majia Nadesan and Leuren Moret appeared as the featured guests on “The Real Deal” hosted by Jim Fetzer to discuss the radiation effects of the Fukushima disaster and the fashion in which it has been covered up both by the Japanese and by the American governments. Nadesan, PhD., a professor of communication in the Division of Social and Behavioral Sciences in the New College of Interdisciplinary Arts and Sciences at Arizona State University, has studied Fukushima extensively.  Moret is an independent geoscientist who has done expert studies on the Fukushima disaster, radiation problems around the world including depleted uranium.  What they had to tell us smacks of politics and public relations and is profoundly disturbing.  This is Part I of the original interview, which can be heard here:

Introduction by Major William Fox

NOTE: I invited Major William Fox (former USMCR commissioned officer), who was instrumental in arranging this interview to prepare an introduction. His key point is that the first line of defense to handle any major crisis is accurate information. Tragically, not only has accurate information been deliberately withheld from Americans regarding the Fukushima crisis, but they have also been steadily fed disinformation.  He continues:

Dr. Majia Nadesan reports in the interview below that on 16 December  2011, The Wall Street Journal wrote that the total radiation dispersed over a broad swath of northern Japan was 15% of what was released from Chernobyl. In contrast, the summary report of the RSMC [Regional Specialized Meteorological Center] Beijing on the Fukushima nuclear accident emergency stated that the total amount of radiation released from Fukushima in the first five days was equal to Chernobyl. In addition, scientists found radio-Xenon levels in the Pacific Northwest at 450,000 times average concentration levels in the weeks following Fukushima — not to mention other dangerous concentrations of radio-nuclides well beyond what any Western Europe countries ever experienced following Chernobyl.

Then we learn from Dr. Nadesan that, “…People in the Pacific Northwest actually inhaled between five and ten hot particles a day in the first month of the disaster — it could take 20 years for cancer to develop or it could take ten years or thirty years. But the significance is that the Western Press in the United States and in Europe as well as in Japan has trivialized the amount of radiation released by using terms like `no acute effects’, `no immediate health effect’…” Dr. Nadesan also comments:

“…If you look at the recently released NRC transcripts, they were projecting the dose to the thyroid of a one year old child, and they had different calculations. But one of their calculations was a thyroid dose of 30 millisieverts just from iodine to the thyroid of a one year old child annualized. And 30 millisieverts is a lot of radiation… clearly there was no effort to make any kind of recommendations to the public to keep their kids inside or to stop drinking milk or dairy, which was found in the wake of Chernobyl to be the primary vector by which small children were exposed to iodine is through milk. And that’s disturbing.”

Read moreFukushima: Radiation, Politics And Public Relations – Part I (Veterans Today)

What’s Inside The Suspect Nuclear Waste Tank At Hanford?

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Rendering of Hanford’s Double-Shell Tanks (DOE image)

– What’s Inside The Suspect Nuclear Waste Tank At Hanford? (Forbes, Aug 27, 2012):

When news broke last week that radioactive material had been found outside of the inner containment wall of a double-hulled tank at the nuclear waste cleanup site in Hanford, Wa, most reports characterized the contents of the tank as “radioactive waste.”But that’s more a category than a description.

The Energy Department has been eager to find out exactly what’s in the tank, which received wastes from leaky single-walled tanks and from more than a half dozen facilities at the Hanford site, including nuclear reactors, plutonium processing plants, a PUREX plant, and laboratories.

DOE funded many studies to analyze the chemical compounds in the tank, determine whether they could corrode the stainless-steel walls, and to anticipate the effects of a spill. Here’s some of what those studies found:

Read moreWhat’s Inside The Suspect Nuclear Waste Tank At Hanford?

Japan Ministry Of Education And Science Admits: Strontium-90 Found In 10 Prefectures

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–  Strontium-90 of #Fukushima Origin Found in 10 Prefectures (Fukushima Diary, July 24, 2012):

Japanese government has started to admit the actual contamination situation because of Fukushima little by little.
On 7/24/2012, Ministry of Education, Culture, Sports, Science and Technology published the data of strontium90. This measured has been done since before 311 monthly. The published data was taken from 4.2010 to 12.2011.

It’s been reported that strontium90 from Fukushima was measured in Fukushima and Miyagi. This data reported it was measured in 10 other prefectures as well,

Tokyo
Kanagawa
Chiba
Saitama
Tochigi
Gunma
Ibaraki
Yamagata
Iwate
Akita

MEXT states the highest reading was 6 Bq/m2 in Hitachinaka city Ibaraki, which was taken in 3.2011.
It was 1/2850 of cesium supposedly, which is harmless for health.

However, 195 Bq/Kg of strontium90 was detected in Yokohama. (cf. Breaking News: Measurement result of Strontium-90)

Source

It took about 15 to 16 months for the Ministry of Education and Science or MEXT (the very name is a joke at this point) to announce radioactive strontium (Sr-90) was widely dispersed from the broken reactors at Fukushima I Nuclear Power Plant last year in 10 prefectures in Kanto and Tohoku, to the levels last seen in the Chernobyl accident.

Caveat is that it excludes Fukushima and Miyagi, probably the two most contaminated with radioactive fallout from the Fukushima accident. MEXT’s excuse is that the stations in these prefectures have been damaged by the earthquake/tsunami.

From the press release by Ministry of Education and Science on July 24, 2012, “Analysis of Strontium-90 in the monthly environmental radioactivity levels (fallout)” (in Japanese; labels added by me):

Asahi Shinbun has a chart that tries to put these numbers in perspective. The bump this time looks slightly bigger than the one after the Chernobyl accident. But Asahi, either in its scientific illiteracy or on purpose to minimize the latest bump, uses the normal scale on the Y-axis instead of a log scale which would make it easier to discern the fluctuations in smaller numbers:

Looking for a historical chart on a log scale, I went to the site maintained by the Japan Chemical Analysis Center. I searched the database, and the 2011 data is already in the database. Here’s the chart I created using the graph function at the site. I added the thin red line later to compare the 2011 level with that after the Chernobyl accident. It does look it is ever so slightly higher. The chart is a log scale, and the data is from all prefectures:

I wonder what the levels would be if Fukushima and Miyagi’s data were to be added. Back to the level during the atmospheric nuclear testing? Or would it exceed that level?